BRNet 2026 Conference Program — The Uncanny Body

The Uncanny Body

Body Representations in Neuropsychiatric Disorders

BRNet 2026 — Padova, June 8–9, 2026

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Organizing Committee

Local Organizing Committee: Enrico Collantoni, Valentina Meregalli, Gaia Risso, Andrea Serino BRNet Committee: Matthew Longo, Catherine Preston Artist credit: Giovanni Pinosio — giovannipinosio.com

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Venues

• 8 June: Aula Magna Galileo Galilei, Palazzo Bo, via VIII Febbraio 2
• 9 June: Aula Morgagni, Policlinico Universitario, Via Giustiniani 2

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Getting There

All nearby airports are well connected to Padova. Venice Marco Polo and Treviso airports offer direct bus services to Padova Train Station. From Verona, take the bus to Verona Porta Nuova station and then a direct train to Padova.

From Padova Train Station: Palazzo Bo is served by Tram SIR1 (direction Sud/Guizza, stop Ponti Romani), while Policlinico Universitario can be reached by lines U6, U14, and U24 (stop Giustiniani Ospedale). Taxis: 049 651333 (24h), available outside the train station.

Home to one of the oldest universities in Europe, Padova has a lot to offer in terms of art, culture, and food. Scan the QR code in the booklet to explore the custom guide with recommended spots for congress info, transport, dining, and exploration.

Accommodations near venues:

• Piazzale Pontecorvo, 33
• Via Gattamelata, 34
• Largo Europa, 9/10
• Via dell’Arco, 2

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Programme

Day 1 — June 8 | Aula Magna Galileo Galilei, Palazzo Bo

Time	Session
09:30–10:00	Registration
10:00–10:20	Welcome
10:20–11:05	Short Talks (Chair: Angela Favaro)
	Manja Engel (Utrecht University) — Why Body Image Disturbance Persists: Impaired Feedback-Based Updating of Body Size in Anorexia Nervosa
	Gabriele Vercelli (University of Roma La Sapienza) — Targeting Body Representation Distortions in Anorexia Nervosa through Interoceptive Conditioning
	Alkistis Saramandi (University College London) — The Petrified Body: A Novel Computational Psychiatry Approach to Body Belief Precision-Weighted Updating in Anorexia Nervosa
11:10–12:00	KEYNOTE: Jamie Feusner (University of Toronto) — When the Brain Misrepresents the Body: Neural, Behavioral, and Computational Models of Body Image Distortion in Psychiatric Disorders
12:00–13:00	Poster Session + Coffee Break
13:00–15:00	Free Lunch
15:00–15:50	ECR Award (Chair: Catherine Preston) — Valeria C. Peviani (University Medical Center Hamburg-Eppendorf): From Sensation to Structure: Inferring the Body in Space
15:50–16:35	Short Talks (Chair: Fabio Sambataro)
	Deniz Yilmaz (Max Planck School of Cognition) — From Body to Brain and Back: Multimodal Evidence for Interoceptive Alterations in Schizophrenia Spectrum Disorders
	Martina Fanghella (University of Milan) — Changes in Intrinsic Activity of the Primary Somatosensory Cortex Causally Explain Differences in Emotion Perception in Autism
	Sara Coppi (Karolinska Institutet) — Body Ownership Shapes Painful Stimuli (Re-)Mapping in Peripersonal Space
16:35–17:00	Break
17:00–18:30	Steering Committee Meeting
19:00–22:00	Social Dinner — Caffè Pedrocchi (upon registration, self-funded)

Day 2 — June 9 | Aula Morgagni, Policlinico Universitario

Time	Session
09:00–10:00	Registration / Posters
10:00–10:50	KEYNOTE (Chair: Matthew Longo) — Michela Bassolino (HES-SO Valais-Wallis): Body Perception in Neurological Disorders: Tools, Mechanisms, and New Perspectives
10:50–11:30	ECR Event — Career Options and Equality, Diversity and Inclusivity Considerations in Research
11:30–12:15	Short Talks
	Piotr Litwin (University of Warsaw) — The Multisensory Correlation Detector Model Explains Temporal Integration in the Rubber Hand Illusion
	Anna L. Vlad (University of Verona) — The Relationship between Body Schema and the Rubber Hand Illusion in Body Dysmorphic Disorder: Experimental Evidence for a Dissociation in Body Representation
	Maren Born (University Hospital Lausanne) — Seeing Myself Sick: Embodying an Infected Virtual Face Alters Behavioral and Immune Responses
12:15–14:00	Free Lunch
14:00–14:50	KEYNOTE (Chair: Andrea Serino) — Olaf Blanke (Swiss Federal Institute of Technology) — Neuropsychiatry of Invisible Presences
14:50–15:35	Short Talks
	Nicola Brunello (University of Bern) — The Effects of Synchronicity on Illusions of Body Perception in Individuals with and without Spinal Cord Injury
	Michel Akselrod (HES-SO Valais-Wallis) — Dynamic Integration of Body Representation and Proprioception During Stroke Recovery
	Francesca Genovese (University of Turin) — Impact of Early Motor Experience on Somatosensory Coding of Visual Self-Identity: Evidence from Cerebral Palsy
15:35–16:30	Poster Prize and Closure Panel

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Short Talks Abstracts

June 8 — Morning Session

I) Why Body Image Disturbance Persists: Impaired Feedback-Based Updating of Body Size in Anorexia Nervosa

M. Engel & V. Peviani Distortions in how people with anorexia nervosa (AN) judge their body size are well known, but it remains unclear whether these reflect negative affect toward the body, inaccurate perception, or difficulty learning from sensory feedback. Understanding these mechanisms is crucial, as they may explain why body image disturbance often persists after weight restoration (Engel & Keizer, 2017). This study examined how individuals currently with AN, individuals recovered from AN (REC), and healthy controls (HC) estimated and updated their perceived body size after receiving self-generated tactile feedback in virtual reality (VR), and whether trait factors influenced this updating process. Specifically, we tested whether higher levels of body image disturbance, bodily intolerance of uncertainty, and attitudes toward touch predicted differences in feedback-based learning. Eighty-three women (24 AN/OSFED, 27 REC, 32 HC) completed a VR task in which they estimated the perceived boundaries of their abdomen before and after visuo-tactile feedback. Healthy controls showed clear improvement after feedback, reducing their estimation error. In contrast, both AN and REC groups showed little change, suggesting a reduced ability to integrate corrective sensory information. Across groups, higher body image disturbance and bodily uncertainty were associated with larger estimation errors, whereas a more positive attitude toward touch predicted stronger improvement. These results suggest that AN is characterised not only by static body size overestimation but also by rigidity in updating internal body models, a process that appears only partially restored after recovery.
Treatments that use sensory feedback to retrain how bodily information is integrated, such as VR-based or body-focused interventions, may help restore flexibility in body representation and reduce persistent body image disturbance.

II) Targeting body representation distortions in anorexia nervosa through interoceptive conditioning

G. Vercelli, R. C. Lima, L. Provenzano, I. Bufalari Bodily self-consciousness emerges from the integration of exteroceptive and interoceptive signals, which together shape the brain’s probabilistic representation of the body as “self.” Interpersonal Multisensory Stimulation (IMS) can induce embodiment illusions and modulate body representations. In anorexia nervosa (AN), characterized by impaired interoception and distorted body image, embodying an ideal, attractive underweight avatar induces the subjective experience of being thinner than usual. Conversely, embodying an undesired, unattractive normal-weight avatar increases overestimation of body size. Integrating interoceptive signals into IMS may enhance embodiment and promote recalibration of maladaptive body representations. In Study 1, healthy participants and AN patients underwent immersive virtual reality embodiment of underweight and normalweight avatars from a first-person perspective. Interoceptive signals were manipulated by providing visual feedback of the avatar’s breathing, either synchronous or asynchronous with participants’ real breathing, combined with synchronous or asynchronous visuo-tactile stimulation delivered to the legs, creating fully synchronous and asynchronous multisensory conditions. Embodiment strength (ownership, agency, location), body image distortion (Body Image Task, Body Schema Task, subjective body size feelings), affective responses (emotional valence, touch pleasantness), and avatar perception (self-similarity, attractiveness, implicit disgust, perceived weight comparison) were assessed. Synchronous IMS increased embodiment compared to asynchronous stimulation, regardless of avatar weight, and was associated with greater pleasantness and more positive emotional responses. Neurotypical participants embodied the normalweight avatar more strongly and rated it as more self-similar and attractive, whereas the underweight avatar was perceived as thinner than their actual body. Observing the underweight avatar from a first-person perspective led participants to select thinner avatars as resembling both their real and ideal bodies. In Study 2, an interoceptive-exteroceptive conditioning paradigm paired a normalweight avatar with asynchronous breathing and visuo-tactile IMS and immediately after an underweight avatar with synchronous breathing and visuo-tactile IMS, aiming to disrupt maladaptive associations between multisensory congruence and distorted body representations. Conditioning increased perceived similarity between the underweight avatar and the real body. Data collection and analysis in AN patients are ongoing. These findings suggest that interoceptive-exteroceptive integration may provide a mechanism to recalibrate distorted body representations, supporting the development of IMS-based interventions for AN and related disorders.

III) The petrified body: A novel computational psychiatry approach to body belief precision-weighted updating in Anorexia Nervosa

A. Saramandi, L. Crucianelli, A. Koukoutsakis, V. Nisticò, L. Mavromara, F. Gonidakis, S. Bertelli, B. Demartini, P.M. Jenkinson, A. Fotopoulou Anorexia Nervosa (AN) is characterised by persistent body image disturbances and reduced insight, contributing to poor prognosis. However, how body-related beliefs form and update across illness stages remains poorly understood. This study examines metacognitive belief updating in AN using a novel computational psychiatry task grounded in predictive processing and Bayesian brain frameworks. Across two multicomponent studies, women aged 18–45 with acute AN (N=46), post-acute AN (N=48), and matched healthy controls (N=102) estimated their body size using interactive 3D avatars under two modalities: an envisioned modality based on perceived body size, and an affective modality based on subjective, felt body image. Participants provided pre-feedback estimates, received explicit feedback derived from actual measurements, and generated post-feedback and post-rotation estimates, alongside confidence ratings. Using multilevel modelling, behavioural error rates were compared between groups, and the Bayesian equation for belief update […|…= …+… /(… + …)(…)]1 was applied to estimate precision-weighted learning rates (…)2, identify parameters predicting posterior estimates and assess the Bayesian optimality of the groups’ belief updating mechanisms. Interim analyses showed body size overestimation in both AN groups vs controls, particularly in the affective modality (.=0.15, p<0.001). Acute AN showed slower learning in the affective but not envisioned modality (vs controls; .=-0.04, p=0.025) indicating diminished integration of disconfirming feedback. Computational modelling indicated greater weighting of prior beliefs over sensory evidence, consistent with findings in cardiac and gastric interoception. This work advances understanding of cognitive-affective mechanisms underlying body-related distortions, suggesting belief-updating difficulties in AN may be domain-specific, and can inform intervention development. Footnotes: 1 Belief Update Equation: …|…= …+… /(… + …)(…); Predicted Posterior Estimate: (…|…); Prior Estimate: (…); Precision proxy of the prior (π.); Evidence: (…); Precision proxy of the evidence (…); 2 Precision-weighted learning rate: …=… /(… + …)

June 8 — Afternoon Session

IV) From Body to Brain and Back: Multimodal Evidence for Interoceptive Alterations in Schizophrenia Spectrum Disorders

D. Yilmaz, L. Deller, J. Spaeth, N. Gottschewsky, B. Karsli, G. Hasanaj, L. Sagstetter, N. Theis, M. Zuliani, A. Weibel, J. Jannan, J. Segerer, M. Hussain, V. Yakimov, J. Moussiopoulou, A. Fourcade, D. Keeser, J. Kilner, L. Roell, M. Gaebler, A. Villringer, A. Schmitt, I. Maurus, P. Falkai
When the brain and body misalign, emotional experience and sense of reality can be disrupted. Although such atypical experiences are central to schizophrenia spectrum disorders (SSD), interoception, processing of internal bodily signals, remains poorly understood in individuals with SSD, particularly across subjective, behavioral, and neural domains. We tested whether SSD is associated with convergent alterations across interoceptive domains and whether these relate to clinical symptoms in a cross-sectional observational design. Patients with SSD (n = 53) and matched healthy controls (HC; n = 60) completed an EEG experiment comprising eyes-closed and eyes-open resting-state recordings and a heartbeat counting task (HCT), followed by self-report measures. Interoceptive accuracy was derived from the HCT, while cortical responses to afferent cardiac signals were indexed by heartbeat evoked potentials (HEP). In individuals with SSD, subjective interoceptive awareness was altered, characterized by impaired regulation and negative bodily appraisal, alongside elevated depersonalization. At the behavioral level, interoceptive accuracy was marginally lower. HEP positivity was attenuated, most clearly during HCT and, to a lesser extent, in eyes-open rest, over centro-parietal regions, consistent with context-dependent alterations in cortical processing of afferent bodily signals. Symptom–interoception links were largely modest, with depersonalization emerging as the most consistent correlate of clinical severity, suggesting that interoceptive disturbances in SSD may reflect a trait-like, intrinsic alteration. Together, these findings indicate that SSD involves pervasive disturbances in bodily self-experience, marked by impaired interoceptive regulation and by context-dependent neural attenuation during interoceptive engagement. This profile highlights interoceptive dysfunction as a disorder-central feature with potential prognostic and therapeutic relevance.

V) Changes in Intrinsic Activity of the Primary Somatosensory Cortex Causally Explain Differences in Emotion Perception in Autism

M. Fanghella, B. Forster Autism Spectrum Disorder (ASD) is often associated with differences in emotion processing, including reduced embodiment—the somatic and sensorimotor re-enactment of observed emotional expressions (Niedenthal 2007, Science). Prior electroencephalography (EEG) research has demonstrated diminished Somatosensory Evoked Potentials (SEP) during emotion perception but not during a control gender task in autistic individuals relative to typically developing (TD) controls, independent of visual processing differences (Fanghella et al. 2022, Journal of Neuroscience). However, the neural mechanisms underlying these differences remain partly unclear. The present study investigated whether reduced somatosensory embodiment of emotions in ASD reflects altered intrinsic connectivity within the somatosensory cortex or it is caused by atypical top-down modulation from higher-order frontal regions, as another recent study suggested (Isakoglou et al., 2023, Translational Psychiatry). We applied Dynamic Causal Modeling (DCM) to VEP-free SEP (Galvez-Pol et al. 2020, Cortex) EEG data, acquired during emotion and gender discrimination tasks in 38 participants (ASD and TD; male and female, 2 females). The model comprised the right primary somatosensory cortex (rS1), right secondary somatosensory cortex (rS2), right supplementary motor area (rSMA), and right inferior frontal gyrus (rIFG). Effective connectivity parameters were compared across tasks and groups to determine the source of task-related modulation. Results indicated that differences in electrocortical responses between emotion and gender tasks were best explained by task-dependent modulation of intrinsic connectivity within rS1 in both groups. Critically, rS1 intrinsic modulations differed significantly between ASD and TD participants. Furthermore, individual differences in task-related intrinsic changes within rS1 significantly correlated with alexithymia traits, suggesting that difficulties in identifying and describing emotions mediate altered embodiment processes. These findings provide causal evidence that atypical intrinsic dynamics within rS1 underlie reduced emotional embodiment in ASD. The association with alexithymia further indicates that emotion-processing differences in ASD may be partly attributable to co-occurring alexithymia traits, rather than autism per se (Cook et al. 2013, Psychological Science). By elucidating the effective connectivity mechanisms supporting embodied emotion perception, this study advances understanding of the neural dynamics contributing to socio-emotional differences in ASD.

VI) Body ownership shapes painful stimuli (re-)mapping in peripersonal space

S. Coppi, M. D’Angelo, H.H. Ehrsson Introduction: When we observe our body, we experience a sense that it belongs to us, known as body ownership. This sense is thought to emerge from multisensory integration between visual, tactile, and proprioceptive signals. Recent findings show that the co-activation of A. and C nociceptors can influence body ownership in a manner similar to touch, highlighting the integration of nociceptive and visual inputs. Beyond the body itself, the space immediately surrounding it, termed peripersonal space (PPS), is crucial for object interaction, threat detection, and self-preservation. While PPS has been widely studied in relation to touch and vision, little is known about how nociceptive information is processed within PPS or how this relates to body ownership. This study aims to investigate visuo-nociceptive processing in peripersonal space and to examine the role of body ownership in this relationship. Methods: We tested our hypotheses in two independent experiments, each involving 24 participants who were naïve to the purpose of the study. The first experiment examined whether visuo-nociceptive processing exhibits peripersonal-space–dependent facilitation (near vs. far space). The second experiment investigated whether this facilitation in near-hand space is modulated by changes in body ownership induced by the rubber hand illusion (RHI) paradigm. In both experiments, participants were instructed to respond as quickly as possible to painful nociceptive stimuli, regardless of whether they were accompanied by flashing visual stimuli. Results: The results of Experiment 1 showed that nociceptive stimuli are subject to crossmodal facilitation within peri-hand space, with participants responding faster when nociceptive stimuli were paired with visual lights presented near the body compared to far from the body. The results of Experiment 2 demonstrated that, within near-hand space, responses were faster when the rubber hand was experienced as one’s own than in a well-matched control condition, indicating that visuo-nociceptive processing is facilitated by body ownership. Conclusions: Together, our findings indicate that nociceptive processing follows peripersonal-space–related multisensory principles and that body ownership shapes these interactions. Pain, like touch, engages peripersonal space mechanisms and is subject to ownership-related modulation within near-hand space, extending peripersonal space research to the nociceptive domain.

June 9 — Morning Session

VII) The Multisensory Correlation Detector model explains temporal integration in the Rubber Hand Illusion

P. Litwin The Rubber Hand Illusion (RHI) demonstrates that body ownership is flexibly constructed in real-time. Since RHI occurrence patterns strongly adhere to key principles of multisensory integration, the illusion can be modeled computationally as an optimal cue integration process. In my presentation, I will outline a novel approach in which RHI occurrence probabilities are modeled as a function of temporal visuo-tactile correlations with the use of the Multisensory Correlation Detector (MCD) model. The MCD model takes continuous multisensory signals as inputs, with highly correlated temporal structures being more likely to be inferred to stem from a common cause and thus be integrated. Although MCD lacks a dedicated Bayesian architecture, it demonstrated optimal performance across various tasks involving simultaneity and temporal order detection, which makes it suitable for modeling of RHI occurrence patterns.

I will present the results of three computational simulations that were carried out using data acquired from psychophysical RHI detection experiments. The results of Simulation 1 show that the MCD accounts for observed probabilities in RHI detection tasks, providing comparably excellent fits to empirical data compared to currently dominating Bayesian Causal Inference (BCI) models. However, since MCD is stimulus-computable and thus sensitive to stimulus-driven effects, it has several unique strengths. Simulation 2 demonstrates that MCD predicts visuo-tactile stimulation patterns with complex temporal structures should lead to higher RHI occurrence probabilities, which has been observed empirically, but for which a computational mechanism has not yet been offered. Finally, Simulation 3 shows that MCD relates skewed distributions of RHI occurrence to asymmetrical time constants in early filtering of visual and tactile signals—and thus to individual differences in temporal binding window widths—suggesting a common mechanism for simultaneity and body ownership perception.

These findings indicate that the MCD model offers a promising, computationally plausible alternative for advancing our understanding of multisensory mechanisms underlying body ownership. In my presentation, I will also outline how the MCD framework can be experimentally validated in the conditions of visuo-tactile stimulation varying in complexity and noise, and how it can account for individual differences in susceptibility to RHI, including in clinical populations.

VIII) The relationship between body schema and the Rubber Hand Illusion in body dysmorphic disorder: experimental evidence for a dissociation in body representation.

A. L. Vlad, M. Scandola

Tsakiris et al. (2005) suggests that the sense of body ownership emerges from the integration of visual, tactile, and proprioceptive information within a stable representation of the body. The Rubber Hand Illusion (RHI) has been used to study this phenomenon. By applying synchronous visuo-tactile stimulation, the perception of owning a rubber hand can be induced. Literature has consistently shown significant individual variability in how susceptible people are to this illusion. Relationships between the body ownership and the body schema, an action-oriented representation essential for motor control (Dijkerman & de Haan, 2007), had been poorly investigated. This gap is evident in clinical populations characterized by Eating Disorders (ED) and Body Dysmorphic Disorders (BDD). This study investigated relationships between body schema and body ownership in individuals diagnosed with ED and BDD compared to healthy controls. Eighteen participants (9 clinical, 9 control) were matched for age (24–30 years), education, and occupational status. For the body schema assessment, participants completed a Mental Body Rotation (MBR) task (Parsons, 1994), judging the laterality of hands and feet displayed at various rotations (0°–330°). For the body ownership assessment, using the RHI paradigm, the illusion is induced by stroking a visible rubber hand and the participant’s hidden hand in four conditions (0°-synchronous touch, 0°-asynchronous touch, 45° clockwise-synchronous touch and 45° anti-clockwise-synchronous touch), collecting proprioceptive drift and subjective embodiment and disembodiment.
A repeated-measures ANOVA showed a significant effect of rotation in the BMR paradigm. In controls, reaction times increased significantly at 150° (p=.025), 180° (p=.002), and 210° (p=.022), compared to 0°. The clinical group didn’t show statistical differences across rotations. Proprioceptive drift and embodiment scores were analyzed in the RHI paradigm . Differences emerged between 0°synchronous e 0°asynchronous (p=.02), as well as between 0°synchronous and 45° synchronous conditions (p=.007). By using Kurtosis and the Bio-mechanical Index (BMI) from the MBR paradigm as covariates, the study found that body schema influences RHI, BMI values predicted greater drift, indicating a positive relationship between body schema stability and susceptibility to the illusion. Healthy participants exhibited higher Kurtosis and more stable representations. These results suggest that a stable body schema is necessary for well-integrated body ownership. In clinical groups, the fragmentation of the body schema may indicate the distorted physical self-perception characteristic of these disorders.

BIBLIOGRAPHY
Dijkerman, H. C., & de Haan, E. H. F. (2007). Somatosensory processing subserving perception and action: Dissociations, interactions, and integration. Behavioral and Brain Sciences, 30(2), 224–239. https://doi.org/10.1017/S0140525X07001641 Parsons, L. M. (1994). Temporal and kinematic properties of motor behavior reflected in mentally simulated action. Journal of Experimental Psychology: Human Perception and Performance, 20(4), 709–730. https://doi.org/10.1037/0096-1523.20.4.709 Tsakiris, M., & Haggard, P. (2005). The Rubber Hand Illusion Revisited: Visuotactile Integration and Self-Attribution. Journal of Experimental Psychology: Human Perception and Performance, 31(1), 80–91. https://doi.org/10.1037/0096-1523.31.1.80

IX) Seeing Myself Sick: Embodying an Infected Virtual Face Alters Behavioral and Immune Responses

M. Born, G. Crespi, C. Jandus, A. Serino The immune system must discriminate between self and non-self. While external agents may pose threats, the self requires continuous monitoring and protection. Self-representations are flexible and can be altered through multisensory integration, as demonstrated by the enfacement illusion. Here, we used a virtual mirror paradigm to investigate how the body responds to seeing oneself as infected. Specifically, we examined whether infection cues alter the ability to embody a virtual face and whether embodiment of an infected face influences behavioral and immune responses. In Experiment 1, participants were exposed to neutral or infectious avatars that either mirrored their movements or moved randomly. Questionnaire ratings demonstrated robust enfacement, with higher ownership and agency ratings following mirror compared to random movements. Importantly, infection cues on the avatar did not reduce the ability to embody the virtual face. Additionally, trait disgust sensitivity positively correlated with ownership ratings, suggesting that individuals with higher disgust sensitivity experienced stronger embodiment of the avatar. In Experiment 2, two cohorts were exposed to infectious avatars that either mirrored their movements or moved randomly. This manipulation allowed us to test whether the immune system responds differently to infection cues attributed to oneself versus another individual. While previous work showed that approaching infectious avatars elicit immune responses, we hypothesized that embodying an infected self would produce stronger immune activation. Capillary blood samples were analyzed using a BioLegend neuroinflammatory panel assessing multiple markers. Preliminary results indicate alterations across several markers following exposure to mirroring infectious avatars. Additionally, an implicit self-recognition morphing task assessed embodiment. Participants judged whether faces morphed between their own face and the avatar’s face at graded levels resembled themselves. Mirroring increased embodiment, as participants were more likely to identify avatar-like morphs as themselves across levels compared to the random movement condition, indicating a shift in the point of subjective equality toward the avatar. Together, these findings suggest that manipulating self-other boundaries in virtual environments influences not only subjective embodiment and affective responses but may also engage immune-related processes. This work provides initial evidence that immune responses to disease cues depend on whether those cues are attributed to the self or to others.

June 9 — Afternoon Session

X) The effects of synchronicity on illusions of body perception in individuals with and without spinal cord injury

N. Brunello, L. Diana, J. Sritharan, V. Moro, B. Lenggenhager, T. Nef, R. Verma, G. Zito Our interactions with the environment are mediated via the perception we have of our own body, i.e., bodily self-consciousness (BSC). Traditionally, this has been investigated via multisensory manipulations, such as the rubber hand illusion (RHI). Importantly, evidence showed that BSC is often altered in clinical conditions such as spinal cord injury (SCI), impacting the daily life of individuals, but its underlying mechanisms are still poorly understood. In our prospective observational study we aim to investigate behavioral and neural correlates of BSC in individuals with and without SCI with a fMRI experiment employing a multisensory stimulation paradigm based on the RHI, to determine the effect of SCI on body perception. Eighteen individuals with SCI (13M; age: 47.1±14.8) and 17 without (12M; age: 46.9±14.6) underwent the fMRI experiment in which tactile stimulation was applied to their legs, while they observed a pair of virtual legs being stroked. The experimental conditions modulated spatial congruency (congruent/incongruent) of the legs and temporal alignment (synchronous/asynchronous) between the seen and the felt touch. After each condition, the participants reported the perceived strength of the illusion (SoI). Behaviorally, we observed a significant group-synchronicity interaction on the SoI (p<0.001). Post-hoc tests revealed a significant between-group difference in the SoI in asynchronous conditions (SCI group perceived a stronger illusion, p<0.05). Preliminary fMRI analyses suggest group-and synchronicity-dependent activations in the right superior parietal lobule and the bilateral postcentral gyri, extending to the supramarginal gyri. Our results suggest that the synchronicity of stimulation is the main determinant of the strength of illusion, with different effects on the two groups. Further imaging investigations will be performed to provide a neural framework for altered BSC after SCI.

XI) Dynamic Integration of Body Representation and Proprioception During Stroke Recovery

M. Akselrod, G. Risso, L. Fleury, O. Blanke, Nathalie Meyer , F. Hummel*, M. Bassolino*

Background: After stroke, impairments in proprioception and altered body representations (BR) can undermine reaching, grasping, and functional independence. Accurate proprioceptive localization depends on combining incoming afferent signals with an internal body model. Although distortions in BR (e.g., altered hand perception, altered ownership) are common after neurological injury, it remains unclear how these distortions relate to proprioception and motor impairment, and whether these relationships change over the course of recovery.
Methods: Alterations in BR were assessed in stroke patients longitudinally across four sessions (acute phase, 3 weeks, 3 months and 12 months from disease onset). Specifically, we evaluated explicit upper limb perception (e.g. ownership) via questionnaire at each session, while we measured the implicit perceived dimensions of the arms (body-landmarks location task) repeatedly across the later sessions. We derived global indices for explicit and implicit limb perception and modeled their trajectories since disease onset and their relationship. Alterations in BRs (implicit and explicit components) were analyzed with respect to motor-based evaluations allowing patients stratification (clustering).
Results: BR recovery did not follow a single uniform trajectory. Instead, the different components showed distinct sensitivity to time and clinical stratification, suggesting partially separable recovery processes associated with explicit and implicit limb perception. Critically, baseline BR and initial clinical/motor status helped explain how BR trajectories evolved.
Conclusion: In stroke, proprioceptive accuracy reflects an evolving interaction between explicit BR, current clinical state, and time. These findings support multi-metric longitudinal phenotyping to stratify patients and to target rehabilitation toward specific BR deficits.

XII) Impact of Early Motor Experience on Somatosensory Coding of Visual Self-Identity: Evidence from Cerebral Palsy F. Genovese, V. Bruno, S. D’Aversa, S. Trombetta, C. Marinaccio, L. Piccinini, F. Garbarini

Previous studies described a behavioral advantage in the implicit processing of bodily-self images (self-advantage)., showing that viewing one’s own body enhances concurrent sensory processing.. This phenomenon is thought to rely on a multisensory bodily-self representation, shaped through sensorimotor experience. However, the role of early motor experience in its development remains unclear. We therefore investigated self-advantage in two groups of patients who suffered motor deprivation at markedly different stages of life: before (congenital) and after (acquired) extensive sensorimotor interaction with the environment. If early sensorimotor experience is essential for bodily-self representation, congenital motor deprivation would impair self-advantage on the affected side, while acquired motor deprivation should not. We recruited 36 hemiplegic patients, 18 congenital (cerebral palsy) and 18 acquired (stroke). Participants viewed images of their own or another person’s right or left hands, and were instructed to respond to tactile stimuli delivered to the corresponding hand. . Performance was assessed (d’)3 and analyzed using a 2x2x2 repeated measures ANOVA (side: affected, intact; identity: self, other; group: congenital, acquired).
A main effect of identity emerged (p=0.000006), indicating the presence of an overall self-advantage effect. Crucially, a sideidentitygroup interaction (p=0.02) showed that in the acquired group, self-other difference was significant for both intact (p=0.007) and affected (p=0.0009) hands. In contrast, in the congenital group, this difference was observed only on the intact side (p=0.0002), being absent on the affected side (p=1).
These findings suggest that early motor deprivation, limiting interaction with the environment, weakens multisensory coding of bodily information related to the affected limb. This opens new possibilities for rehabilitation in congenital motor deprivation, indicating that interventions aimed at strengthening the multisensory representation of the affected limb could enhance bodily-self and multisensory processing.

References

1. Frassinetti, F., Pavani, F., Zamagni, E., Fusaroli, G., Vescovi, M., Benassi, M., … & Farnè, A. (2009). Visual processing of moving and static self body-parts. Neuropsychologia, 47(8-9), 1988-1993.
2. Galigani M., Romeo M., Scanferlato N., Valeriani M., Bettina F., Garbarini F. (2025). Somatosensory coding of visual self-identity. NeuroImage, 318.
3. Stanislaw, H., & Todorov, N. (1999). Calculation of signal detection theory measures. Behav Res Methods Instrum Comput, 31(1).

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Poster Abstracts

Note: Poster numbering follows the original booklet. Some apparent gaps in the sequence reflect footnote/reference numbers that share the same counter as poster numbers in the original PDF — the content is complete as extracted.

1) Bodily self disturbances differentiate persistent postural-perceptual dizziness from other otoneurological disorders

M. Gobinet, M. Elzière, J. Léonard and C. Lopez Persistent Postural-Perceptual Dizziness (PPPD) is among the most prevalent chronic neuro-otologic disorders, accounting for 15–20% of adults seen in neurology and specialized dizziness clinics. Classified as a functional vestibular disorder and defined by established diagnostic criteria, PPPD typically follows peripheral or central otoneurological disorders. However, the mechanisms underlying the transition from these disorders to chronic perceptual dizziness remain unclear. Beyond maladaptive postural control and increased visual dependence, theoretical models implicate altered multisensory integration and disrupted predictive processing. Such mechanisms may extend to disturbances of the bodily self, which have not been systematically investigated in PPPD. Thus, we aimed to characterize bodily self disturbances in PPPD by assessing depersonalization-derealization symptoms in a large clinical cohort. We conducted a cross-sectional study including 455 participants (100 patients with PPPD, 180 patients with other otoneurological disorders, and 175 healthy controls). Depersonalization-derealization symptoms were assessed using the Cambridge Depersonalization Scale, alongside measures of anxiety and depression (Hospital Anxiety Depression Scale and State Trait Anxiety Inventory), dizziness-related impairment (Dizziness Handicap Inventory [DHI]), and PPPD symptom severity (Niigata PPPD Questionnaire [NPQ]).
PPPD patients exhibited markedly elevated depersonalization-derealization symptoms compared with both other otoneurological disorders and healthy controls. Twenty percent of PPPD patients met the clinical depersonalization-derealization threshold, compared with 7.2% of other otoneurological disorders, and <1% of controls. Depersonalization-derealization severity in PPPD overlapped with levels observed in other functional neurological disorders but remained lower than those reported in primary dissociative disorders Factor analyses identified three dimensions: Bodily Self Disturbances, Cognitive and Affective Detachment, and Numbing. Only Bodily Self Disturbances, capturing disruptions in core bodily self dimensions (self-location, agency, body ownership, and first-person perspective), robustly differentiated PPPD from other otoneurological disorders, predicted PPPD diagnosis, and showed significant discriminative ability, comparable to DHI and NPQ. Structural equation modelling confirmed a strong direct effect of PPPD on Bodily Self Disturbances, only partially mediated by depressive symptoms and independent of age, sex, migraine, and anxiety. These findings identify depersonalization-derealization as a previously unrecognized component of the PPPD phenotype and establish bodily self disturbances as a promising clinical marker for refining phenotyping and informing pathophysiological models of PPPD.

2) They’re having a very different eating disorder experience to their cisgender counterparts”: an exploration of the way in which non-binary and gender non-conforming people experience disordered eating.

R. Knight, F. Sonko, N. Dixon & E. Caldwell Introduction: Our understanding of what an eating disorder is limited by a narrow research focus, meaning that many with these experiences are missed. Preliminary research indicates that transgender individuals have been particularly affected by this.
Method: We conducted six semi-structured interviews, analysed through reflexive thematic analysis. Results: We generated five themes around the motivations for disordered eating and the influence of gender. Conclusion: Understanding motivations for disordered eating is vital. We call on researchers to be aware of the limitations of generalizations from unrepresentative data, and underline the need to broaden our understanding of what an eating disorder is.

3) Emotional Benefits of Facial Touch Techniques: A Psychodermatological Perspective

K Steventon Facial touch techniques – massage and structured self-massage – appear to support emotional wellbeing through converging skin–brain and muscle–brain mechanisms. Clinical and experimental data show that facial massage can acutely reduce state anxiety and negative mood, and that repeated neuromuscular/myofascial facial work plus self-massage may produce sustained reductions in depressive symptoms and state anxiety alongside normalization of facial muscle tone. From a psycho-dermatology view, these effects are plausibly mediated by bidirectional skin–brain signalling pathways that integrate sensory, autonomic and affective processes. Gentle stroking and low-force pressure on facial skin optimally stimulate C-tactile (CT) afferents and other mechanosensory fibres, which project to insular and limbic regions and are associated with pleasant, soothing touch, pain modulation and improvements in emotional wellbeing.

Simultaneously, myofascial facial massage and self-massage target hyperactivity in emotionally responsive facial muscles, reducing nociceptive input and myofascial pain while shifting autonomic balance towards parasympathetic dominance. Lowering tonic activity and parafunctional patterns in these muscles can accompany substantial improvements in mood and anxiety, consistent with a facial-feedback–type mechanism in which chronic tension feeds into negative affect and its relief contributes to emotional recalibration. Repeated experiences of a relaxed jaw or softened frown may therefore help “reset” limbic–cortical circuits involved in stress and emotion regulation, shifting the individual’s baseline toward greater calm, perceived safety and positive affect rather than transient relaxation alone.

Emerging preclinical work further suggests that gentle manual lymph drainage of the head and neck can enhance glymphatic-like and meningeal lymphatic clearance of metabolic waste, reduce Alzheimer-like pathology and improve cognition in animal models, offering a plausible additional route by which face- and neck-focused interventions could support emotional regulation and cognitive clarity, although human evidence is pending. Taken together, this body of work supports the concept of “emotional effects of facial touch techniques” as a low-risk, psychodermatology-based approach that leverages affective touch, neuromuscular relaxation, appearance-related social signalling and emerging lymphatic mechanisms to modulate emotional wellbeing.

The face is a highly visible extension of the skin–brain axis and functions as a core representation of our identity, signalling health, emotion and social belonging to others. Improvements in skin quality and facial appearance carry evolutionary and social significance: facial skin and expression function as salient signals of health, vitality and emotional state that shape social perception, attractiveness and social support, all of which feed back into self-esteem and emotional wellbeing.

4) A body worth the effort: Reduced effort discounting in individuals with greater body image disturbance

P. M. Jenkinson, S. Y. Hsu, A. Koukoutsakis, P. Lockwood, M. Apps & A. Fotopoulou Rationale: Decision making involves weighing potential rewards against possible costs. While extensive research has examined how decisions are affected by risk or uncertainty, substantially less is known about how physical effort is integrated into decision making. Our previous work has shown that different cost dimensions (e.g. risk versus loss) dissociate eating-related and appearance-related behaviours (Jenkinson et al., 2023, 2024). Here, we examine whether physical effort discounting varies with individual differences in body image disturbance (BID), which might help explain seemingly paradoxical behaviours, whereby extreme effort is exerted despite any obvious physical benefits. Method: 89 women from the general population completed the BID-Q (Cash et al., 2004), and a physical effort-based decision-making task in which they chose between a small reward requiring no effort and a larger reward requiring increasing levels of physical exertion (Lockwood et al., 2017). Behavioural and computational variables were calculated to characterise how reward value declined as a function of effort, including: 1) proportion of offers accepted dependent on level of i) effort and ii) reward; and 2) k-values – which quantify how rapidly the subjective value of a reward declines with increased physical effort. We examined how these indices related to BID. Results: Greater BID was associated with significantly reduced effort discounting (k-values), i.e. individuals with higher BID maintained reward value despite increasing physical effort demands. Conclusion: Our findings suggest that effort costs are differently weighted in individuals with higher BID, which may account for why some people choose to exert effort beyond any obvious health benefits.

5) Do Humans Automatically Prioritise Hands Over Other Body Parts? A Systematic Review of Visual Attention Studies

Hsin-Yuan Chen Although the space near the hands and functionally meaningful hand postures receives automatic attentional benefits, the evidence does not support a general, automatic prioritisation of hand perception over other body parts. Synthesising evidence from 120 sources reveals that while hands are highly salient stimuli that strongly modulate visual attention, the claim that they are automatically prioritised over all other body parts is not consistently supported. The main finding is an automatic attentional prioritisation of the space near an individual’s own hands, leading to faster processing of stimuli within reach and enhanced cognitive control. This effect appears largely automatic, occurring with brief stimulus presentations and without conscious intent, and is likely mediated by dedicated bimodal visuo-tactile neural systems. When considering images of hands as visual objects, evidence for prioritisation depends on the situation. Functionally significant or anomalous postures, such as hands interacting with objects or in distorted configurations, are particularly effective at capturing attention. However, in direct comparisons with other body parts, a clear hierarchy is not established. Some studies find an advantage for hands over other body parts, such as the head or torso, in specific tasks, but others report no difference among hands, feet, and bodies. Although many hand-related attentional effects show signs of automatic processing, such as occurring under high perceptual load or without awareness, they are also clearly modulated by top-down factors such as task demands and instructional sets. The evidence thus points to a broad conclusion: automatic attentional mechanisms enhance processing of the space near the hands and of meaningful hand postures, but a universal, automatic priority for hands over all other body parts in all contexts is not supported by the current literature.

6) Towards a Tactile Imagery Ability Assessment Tool

R. Lustenhouwer Tactile imagery (imagined touch) has attracted growing fundamental and clinical interest, from investigating bottom-up vs. top-down processing in tactile perception, to exploring therapeutic potential. However, no tools currently exist to assess one’s tactile imagery ability. Given individual variability, both across and within imagery modalities, a domain-specific tactile imagery assessment tool is needed.

We developed and tested a comprehensive Tactile Imagery Ability Assessment Tool (TIAAT). Based on tactile literature, it covers a range of active (haptics) and passive (somatosensation) touch types. Trained assessors instructed ±140 healthy participants to imagine different touch types and rate imagery vividness and their ability to maintain and control each sensation on 5-point Likert-scales (72 items). Active touch varied by object (plastic bottle, modeling clay, sponge) and property (temperature, weight, texture, resistance). Passive touch varied by body site (lip, shin, sole of the foot, lower back) and sensation (stroking, vibration, pinching).

Overall, participants were able to perform tactile imagery: the vast majority reported at least some imagery across touch types. Individual variability was substantial: scores bridged both ends of the scale. Active tactile imagery differed significantly between objects, depending on tactile property. Object-property pairs with particularly strong imagery were bottle-temperature, bottle-weight and sponge-texture, whereas bottle-resistance elicited weaker imagery, as did temperature and weight for both sponge and clay. Passive tactile imagery was significantly stronger for body sites with higher receptor density (i.e. lip and foot). Imagery of stroking was significantly weaker than vibration and pinching. Active tactile imagery was slightly, yet significantly stronger than passive imagery. Active and passive imagery showed a strong, positive correlation, though some participants had relatively strong active imagery, but weaker passive imagery, or vice versa.

Our findings confirm that tactile imagery ability varies across individuals and touch types, underlining the importance of a comprehensive imagery ability assessment tool specific to the tactile domain. The TIAAT is currently being revised. We aim to reduce the number of items, making it more concise and applicable in research and clinical settings, while sustaining a variety of touch types to reflect the rich spectrum of our sense of touch.

7) In My (Virtual) Body: Gender Congruency Shapes Ownership and Agency

Marina Leggieri, Borriero Alessio, Ciorli Tommaso, Pyasik Maria, Finzi Sarah, Molo Maria Teresa, Pia Lorenzo Gender identity, understood as the set of beliefs and self-representations related to one’s gender, shapes bodily experience at both reflective and pre-reflective levels (Fausto-Sterling, 2019). When an individual’s physical appearance does not align with their affirmed gender, this incongruence may produce distress and feelings of disembodiment, fostering detachment from one’s body.

We investigated how gender congruency influences embodiment using a gender-congruent or gender-incongruent Full Body Illusion (FBI) in immersive virtual reality. Participants rated ownership and agency over the avatar using the Avatar Embodiment Questionnaire (AEQ) and completed the Utrecht Gender Dysphoria Scale–Gender Spectrum (UGDS-GS) to assess dysphoria and gender affirmation.

All participants reported a convincing illusion of embodiment. However, condition effects differed by group: transgender participants showed a marked modulation of embodiment depending on avatar congruency, reporting stronger ownership in the gender-congruent condition, a result confirmed by bootstrapped analyses. Moreover, dysphoria was positively associated with mirror-related embodiment, whereas affirmation was negatively associated with agency.

These findings indicate that embodiment depends not only on multisensory integration but also on the alignment between the perceived body and one’s affirmed gender. Gender identity thus emerges as a dynamically enacted and deeply embodied dimension of minimal selfhood, bridging sensorimotor processes and the phenomenology of bodily consciousness.

8) Recognising heterogeneity in body perception disturbances in CRPS: PPI Co-Development of a VR tool for personalised hand manipulations

C. Naylor, C. Lutteroth, G. Buckingham, & J. Bultitude Introduction Disordered body representations are common in Complex Regional Pain Syndrome (CRPS), yet the exact nature of these disturbances varies markedly across individuals. Clinical interventions targeting body perception disturbances often overlook this heterogeneity, typically adopting a one-size-fits-all approach with varied effectiveness. Interventions may be improved if they are tailored to an individual’s unique disturbances. We worked with people with CRPS to co-develop a novel virtual tool that enabled them to create and embody virtual hands that model their distorted limb perceptions, and what they desire their limb perceptions to be.

Methods Adopting a Patient and Public Involvement approach, four individuals with upper-limb CRPS co-created three embodied virtual hand models: (1) a typical hand, (2) their currently perceived distorted hand, and (3) their desired hand representation. They provided iterative feedback on the VR hands and reflected on perceptual, cognitive-affective, and sensorimotor experiences during embodiment.

Results We created a tool that facilitated dynamic, real-time personalisation of VR hands. PPI partners found the tool to be accessible, engaging and expressed enthusiasm for its application to the assessment and treatment of CRPS. Embodiment of different VR hand models influenced body perception, pain, motor control and affective responses, with individualised response patterns.

Discussion Findings highlight the importance of personalisation when targeting body perception disturbances. Personalised virtual embodiment offers a novel experimental and translational framework for measuring, communicating, and rehabilitating disordered body representation in clinical populations.

9) When acting shapes the body: exploring the dynamic interplay between sense of agency and sense of ownership using immersive virtual reality

G. Stanco, M. Mariano, C. Negrone, F. Massaro, A. Sterlicchio, A. Gabbiadini, G. Salvato, L. Zapparoli Bodily self-awareness relies on two core dimensions: the Sense of Agency (SoA), referring to the experience of controlling one’s own actions, and the Sense of Ownership (SoO), referring to the experience that one’s body belongs to oneself (Seghezzi et al., 2019). Although these experiences can dissociate, they typically co-occur and may mutually influence each other; however, the nature and the extent of their interaction remain unclear. Here, immersive virtual reality (VR) provided a controlled yet ecologically valid context in which SoA and SoO could be systematically manipulated and measured. The aim was to examine their potential dynamic interplay and to clarify how they jointly contribute to bodily self-representation. Fifty-six healthy participants performed a simple task in VR: pressing a button to switch on a lightbulb. SoA was manipulated by contrasting self-generated (active) and externally generated (passive) actions and by introducing variable temporal delays between action and outcome. SoO was manipulated by displaying virtual hands either spatially aligned with participants’ real hands (anatomically congruent condition) or swapped between sides (anatomically incongruent condition). SoA and SoO were assessed using explicit self-report ratings and implicit indices: intentional binding (IB), indexing SoA through perceived temporal compression between action and outcome (Haggard et al., 2002), and proprioceptive drift (PD), indexing SoO through perceived displacement of the real index finger toward the virtual one (Tsakiris et al., 2005). Explicit ratings showed reciprocal modulations. Agency ratings were higher for active actions and further enhanced by bodily anatomical congruence. Active movements also increased explicit SoO, indicating a contribution of motor engagement to body-related self-attribution. Implicit measures revealed a partially different pattern. PD showed reduced SoO in the incongruent condition. IB emerged only in the presence of action–outcome contingency and was not modulated by anatomical plausibility, indicating that movement control outweighs anatomical congruency in shaping implicit SoA. Overall, these findings demonstrate a bidirectional interplay between SoA and SoO, characterized by distinct explicit and implicit patterns, supporting an integrative account of bodily self-awareness.

10) The role of social interactions in modulating body ownership across development: evidence from the rubber hand illusion

L. Della Longa, A. Mele, U.G. Pesci, I. Guglielminetti, T. Farroni From early development, the human brain gradually constructs a multisensory representation of the body that supports the self-other distinction. This representation relies on a dynamic balance between stability and flexibility. Interpersonal motor interactions, which require the integration of sensorimotor signals at multiple levels, are likely to contribute to the formation maintenance of this bodily framework. However, how body representations adapt during social interaction – particularly across developmental stages marked by rapid physical and social change – remains unclear. During motor synchronization, individuals must integrate representations of their own body with those of an interacting partner, stablishing a shared sensorimotor framework while preserving self–other distinction. The present study investigated how social interaction modulates body representation in young adolescents (N = 54; 11–13 years) and adults (N = 49; 19–35 years), examining the distinct and combined contributions of sensory cues. Body ownership and proprioceptive location were assessed using the Rubber Hand Illusion (RHI). Participants first completed a baseline RHI condition with synchronous and asynchronous visuo-tactile stimulation. The synchronous condition was subsequently repeated following an interactive motor synchronization task performed under three sensory conditions (visual, tactile, visuo-tactile), presented in counterbalanced order. Adolescents exhibited greater bodily flexibility than adults, showing embodiment of the rubber hand even in the absence of synchronous tactile stimulation, suggesting heightened sensitivity to visual body-related cues. Both age groups reported increased subjective embodiment following the motor interaction relative to baseline, regardless of the sensory modality involved. However, sensory channels differentially affected proprioceptive drift: tactile interaction was less susceptible to the illusion and remained more anchored to initial proprioceptive signals. Overall, these findings reveal developmental differences in body representation and demonstrate that multisensory social interaction enhances flexibility of body ownership while selectively modulating perceived body location. These results provide new insights into multisensory integration during dyadic social interactions across development.

11) Applying automated head position detection during infants sleep for torticollis screening

N. Yakoub, M. Goncalves Maia, P. Jána, M. Hoffmann, S. Berger Introduction Infant torticollis involves unilateral neck muscle tightness that can contribute to feeding difficulties [1], craniofacial asymmetries, and later postural problems [2]. Early detection and timely physical therapy improve outcomes [3], but scalable screening remains limited. Because torticollis constrains head orientation, sleep head-position patterns may provide an early behavioral marker. Recent advances in computer vision and deep learning make automated detection of head position from home videos increasingly feasible. We hypothesized that during sleep infants with torticollis (1) spend less time with the head centered (PC) and (2) show greater lateralization, i.e., spend a higher proportion of time on the dominant side (PD). Methods Infants (N = 33; 13 female) with a mean (SD) age of 6.10 (2.07) months were recruited following torticollis screening by a pediatric physical therapist. 20 infants were diagnosed with torticollis. Enrolled families used a commercially available, infra-red, baby monitoring camera mounted over infants’ cribs. Video was obtained from the baby monitor company. Trained coders annotated 4 hours of video from one night per baby for onset/offset of head position (‘left’, ‘center’, ‘right’). Transitions were coded as ‘undetermined’. Regression models tested whether torticollis diagnosis, sex or age predicted PC or PD. In parallel, automated approaches (OpenFace 2/3, Gaze360) will be evaluated, using facial landmarks and body keypoints to classify head position. Preliminary results Infants with torticollis had a mean (SD) PC of 0.41 (0.29) and PD of 0.46 (0.22), whereas the control group had PC of 0.50 (0.31) and PD of 0.38 (0.28). Groups did not differ on PC (t = 0.68, p = 0.507) or PD (t = -0.90, p = 0.377). Regression analyses showed no association between torticollis diagnosis and PC (b = -0.19, z = -0.30, p = 0.761) or PD (b = 0.24, z = 0.49, p = 0.620).

Future directions Observed patterns were consistent with the hypotheses, suggesting that larger samples may be required to detect statistical significance. Automated head-position detection will enable efficient scaling to improve power and evaluate sleep head-position metrics as a potential screening aid.

References: [1] Genna CW. Breastfeeding Infants with Congenital Torticollis. Journal of Human Lactation. 2015;31(2):216-220. doi:10.1177/0890334414568315 [2] Kuo, A. A., Tritasavit, S., & Graham Jr, J. M. (2014). Congenital muscular torticollis and positional plagiocephaly. Pediatrics in review, 35(2), 79-87. https://doi.org/10.1542/pir.35-2-79
[3] Aarnivala, H., Vuollo, V., Harila, V. et al. Preventing deformational plagiocephaly through parent guidance: a randomized, controlled trial. Eur J Pediatr 174, 1197–1208 (2015). https://doi.org/10.1007/s00431-015-2520-x

12) The Pre-Session Co-Therapist: Co-Designing Atmospheres of Agency in Child and Adolescent Psychiatry

Y. Cho, S. Vilhem, R. Barbe In child and adolescent psychiatry, the pre-consultation interval, situated in the waiting area, is not a passive administrative phase but a critical determinant of clinical engagement. It acts as a liminal threshold where the civilian subject transitions into the patient role. However, standard hospital environments often feature clinical sterility and surveillance-oriented aesthetics, conditions that exacerbate anticipatory anxiety, induce behavioral inhibition, and compromise the therapeutic alliance. Drawing on frameworks from institutional psychotherapy and eco-phenomenology, this study positions the built environment as an active variable in treatment outcomes. To operationalize this impact, we applied a five-dimensional systemic framework, assessing complexity, entropy, negentropy, position, and trajectory, to analyze clinician feedback on admission bottlenecks. This diagnostic process revealed that intake scenarios typically suffer from high environmental entropy (unpredictability of the clinical process) and a marginalized subject position (systematic exclusion of patient agency). In response, we analyze a site-specific intervention at the Maison de l’enfance et de l’adolescence (MEA) in Geneva, Switzerland: a co-designed paper-and-light installation paired with patient-led “check-in cards.” We theorize the installation’s clinical utility through a quadripartite functional model, expanding Delion’s triad (phoric, semaphoric, metaphoric) with a proposed fourth dimension of the aesthetic function (care through sensory transformation). We demonstrate that creative practices support social cohesion and clinical utility only when: (1) co-designed across sectors (democratizing safety protocols); (2) supported by dedicated coordination (embedding artistic affordances into risk protocols); and (3) given institutional time to bridge the epistemological gap between clinical logic and patient experience. Ultimately, the intervention functions as a “pre-session co-therapist,” transforming the wait into a therapeutic rite of passage and validating atmospheric design as a structural necessity for democratic healthcare infrastructure.

13) Hands Shape Visual Attention: A Systematic Review of Near-Hand Effects and Embodiment

Hsin-Yuan Chen This systematic review synthesises evidence from 61 studies on how hands and body parts influence visual attention and attentional bias, with emphasis on embodiment and automaticity. Across behavioural, eye-tracking and ERP paradigms, the presence of the observer’s own hand near visual stimuli reliably facilitates target detection, particularly in near-hand space. Facilitation is strongest for one’s own hand, extends to tools or others’ hands after joint action or training, and is spatially organised around functional grasping zones rather than simple distance. Electrophysiological data show early non-selective sensory gain increases followed by later task-selective enhancements. Effects are partially automatic, occurring without task relevance, visibility or awareness, but modulated by top-down goals, ownership, posture, and valence. Exceptions reflect distinct perceptual vs attentional control processes. Findings support multisensory, body-centred representations that prioritise near-personal space for action, moderating apparent contradictions through stage-specific and contextual mechanisms.

14) The Emergence of Contrast Effects when Rating Body Types are not Impacted by Context nor Self-Perception of Body Size

A. Karlinsky, S. L. Wang, C. Pilieci, M. F. Vani, C. M. Sabiston, T. N. Welsh The “Cheerleader Effect” refers to the finding that faces of individuals are perceived as more attractive when the faces are presented in groups compared to when the faces are presented alone. The current studies were designed to examine if a Cheerleader Effect emerges for perceptions of body size by determining if the perception of body size is influenced by the size of the bodies presented in the group. Participants (young adult women ages 18-25 years; Exp 1, n=50; Exp 2, n=30) rated the perceived body size of a centrally-presented model on a continuous scale from “very thin” to “very heavy”. There were 15 “target” models (5 body sizes by 3 models) presented either on their own or in groups of three. When presented in groups, the two models on either side of the central target model could have a similar body size or a body size that was smaller or larger than the central target model. In Exp 1, models were presented on a white background. In Experiment 2, models were presented in either a gym or office setting. Analysis of the ratings did not reveal an overall Cheerleader Effect because there were no differences between the ratings for a central model when the model was presented alone or alongside groupmates of a similar body size. A contrast effect emerged, however, in which the central model was rated as thinner when presented alongside groupmates of a heavier body size (p<.05), and as heavier when presented alongside groupmates of a thinner body size (p<.05). These contrast effects did not differ according to context (neutral, office, or gym) nor in groups of participants who viewed their own bodies as too thin vs. too heavy. These findings provide evidence that the representation and perceptions of body size are influenced by factors such as whether or not the body is presented alone or in a group, but there was no evidence that perception of body size was influenced by context or the viewer’s perception of their own body size.

15) Body image-Related Attitudes Mediate Avatar Embodiment in Virtual Reality

T. Welsh, D. Thibodeau, A. Mazalek, C. Sabiston, X. Wang Body image-related attitudes, such as body appreciation and internalized body size bias, shape how individuals perceive their own body. Virtual reality (VR) offers a platform for interventions that may alter body perception by allowing users to embody a virtual body (i.e., an avatar) that differs from their own physical body. How pre-existing body image attitudes influence the virtual embodiment process remains unclear. In this study, a body-scaled affordance paradigm was used to examine how embodying avatars with altered body size (20% smaller, equal, or 20% larger) affects body perception in VR, and how this effect is modulated by body image attitudes. For the body-scaled affordance tasks, participants (women n=36; men n=33; aged 18-25 years) encountered an aperture (space between two poles) of varying widths and were asked to determine the minimal aperture (distance between two poles) through which they could pass when they turned and walked sideways (i.e., sidling) without knocking a pole over. These tasks were performed in both VR and unmediated (UR, i.e., physical) reality. There were two versions of the task: 1) an action task in which they walked sideways through the apertures; and 2) a perception task in which they stood approximately 2m from the poles and visually estimated the minimum aperture. The action task was performed 2 times - once in UR and then once in VR. The perception task was performed 3 times – once in VR and twice in UR, before/after VR. Affordance-based indices of body-size were computed from action and perception thresholds, adjusted for VR-specific perceptual distortions, to derive an embodiment index quantifying the extent to which participants adapted to their avatar’s body size. There were three main findings. First, participants visually overestimated their body size in VR compared to UR. Second, the overestimation in VR persisted when participants returned to UR. Third, regression analyses revealed that for male participants, higher body appreciation and lower internalized body size bias were associated with a greater sense of embodiment of a differently-sized avatars. These findings suggest that body image-related attitudes may facilitate perceptual adaptation to altered body representations in VR.

16) The effects of visual impairment on body representation: insights from the MySpace Project

L.Coelho, M.Gori In humans, vision is the most accurate sensory modality for constructing spatial representations. Visual impairment has been shown to negatively affect daily functioning and overall quality of life. For example, studies have shown that spatial and locomotor abilities are reduced in visually impaired populations. One hypothesis is that these difficulties arise from distortions in body representation. Accurate body representations are essential for motor control, as we use our bodies as a metric guide for our actions. Although body representation is a byproduct of multisensory integration, it has been suggested that vision plays a critical role in calibrating and refining these representations. In a series of experiments within the MySpace project, we examined how visual experience shapes haptic body representations in both sighted and visually impaired (VI) individuals. Specifically, we focused on two core components of body representation: (1) size perception (2) the plasticity of the proprioceptive system. To investigate these aspects, we employed multiple methodologies, including landmark localization tasks, psychophysical measures, and the rubber hand illusion. In sighted participants, we observed distortions in haptic body representations, whereas visual body representations remained relatively accurate. VI participants, however, exhibited distortions in hand and foot size across several haptic tasks. Furthermore, VI children did not update their perceived body location during the rubber hand illusion, suggesting reduced proprioceptive plasticity. Taken together, these findings support the hypothesis that vision plays a crucial role in reducing distortions within haptic body representations. We further propose that children with visual impairment may develop with less calibrated representations of their own bodies.

17) Altered bodily self-perception in chronic spinal cord injury: associations with daily functioning, quality of life, and emotional status

L. Diana, N. Brunello, J. Sritharan, V. Moro, B. Lenggenhager, T. Nef, R. K. Verma, and G. A. Zito Following a spinal cord injury (SCI), individuals may experience alterations in bodily self-perception, including illusions of altered body size, distorted spatial localization of body parts, and reduced body ownership. Although such disturbances are increasingly recognized, their impact on different domains of daily functioning remains insufficiently understood. The present study aimed to investigate the associations between altered bodily self-perception and key aspects of daily living, including pain, sleep quality, life satisfaction, emotional status, and participation in activities of everyday life.

We recruited 25 individuals with chronic spinal cord injury (SCI; time since injury > 1 year; 18 males; mean age 47 ± 14 years) and 24 age- and sex-matched individuals without spinal cord injury (19 males; mean age 47.4 ± 14 years). Different aspects of bodily self-perception were assessed using a modified version of the Body Feelings and Illusions after Spinal Cord Injury questionnaire (BoFI-SCI). All participants completed a comprehensive set of standardized questionnaires, including the Satisfaction with Life Scale (SWLS) to assess quality of life, a visual analogue scale (VAS) for pain intensity, the Pittsburgh Sleep Quality Index (PSQI) for sleep quality, the Multidimensional Assessment of Interoceptive Awareness (MAIA), the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) to evaluate participation in daily activities, and the Spinal Cord Independence Measure (SCIM) to assess functional independence. Emotional status was evaluated using the Positive and Negative Affect Schedule (PANAS) and the Hospital Anxiety and Depression Scale (HADS).

Compared to individuals without SCI (Mann–Whitney tests), participants with chronic SCI reported significantly higher BoFI-SCI scores (indicating more frequent alterations in bodily self-perception), greater pain intensity, reduced life satisfaction, lower participation in daily activities, and higher levels of depressive symptoms. Spearman correlation analyses revealed an association between these variables, i.e., greater alterations in bodily self-perception were significantly associated with lower life satisfaction, poorer sleep quality, higher pain intensity, and more pronounced depressive symptoms.

These findings suggest that altered bodily self-perception in SCI is closely linked to clinically relevant aspects of psychological well-being and daily functioning. Addressing bodily self-perception disturbances may therefore represent a promising target for rehabilitation interventions aimed at improving quality of life and participation in individuals with chronic SCI.

18) Exploring neural markers of temporal processing in Peripersonal Space.

A. Custo, I. Chauhan, L. Hazebroucq, M. Akselrod, T. Bertoni, A. Serino Peripersonal Space (PPS) refers to the space immediately surrounding the body that the brain encodes as behaviorally salient for thriving and survival. This system relies on a distributed fronto-parietal network that integrates multisensory bodily signals (e.g., tactile and proprioceptive cues) with external sensory (e.g., visual, auditory) events as a function of their spatial proximity. Classic studies have shown that multisensory interactions are enhanced when stimuli occur near the body compared to far space, supporting a space-based definition of PPS as a protective and action-oriented buffer zone. However, everyday interactions unfold not only across space but also across time. Efficient action requires predicting when contact is likely to occur, suggesting that temporal congruency may be as fundamental as spatial proximity in shaping PPS responses.

We propose an extension of the traditional framework toward a Peripersonal Space-Time (PPST) field, in which the brain’s response depends on the joint spatiotemporal congruency of multisensory events. In this view, PPS mechanisms prioritize conditions that maximize the probability of imminent interaction, integrating where and when signals converge.

To test this hypothesis, we recorded EEG activity during a visuo-tactile task in which visual stimuli were presented at two distances (near vs. far from the hand), either unimodally or paired with tactile stimulation at nine stimulus onset asynchronies. We measured beta-band activity over a centroparietal cluster (Bertoni et al., Cell Reports Medicine, in press), and compared it for modality (tactile, visual, visuo-tactile), spatial (near, far) and temporal (SOAs) features.

Preliminary results (N = 17) indicate stronger responses in high-beta for near vs. far stimulation, both for visual and visuo-tactile stimulation, confirming the spatial determinants of PPS processing. Investigating spatiotemporal combinations for visuo-tactile stimulation, a frequency-specific sensitivity emerged: low-beta activity is more responsive to spatial congruency, whereas high-beta activity is more sensitive to temporal congruency. Increasing SOA progressively reduces the spatial determinant of visuo-tactile stimulation. Ongoing data collection is testing the specificity of the effect for hand-centered multisensory encoding.
Together, these preliminary findings support a unified PPST framework in which spatial and temporal regularities are encoded within a common network, multiplexed across distinct beta-band frequencies.

19) No evidence of tactile distance anisotropy on the lips

K. Jennings, E. Ferrè, M. Longo A growing volume of research provides evidence of an illusion in tactile distance perception experienced by healthy individuals. Typically, people report that the distance between two stimuli placed on the body horizontally feels larger on a skin surface than when stimuli are placed vertically. The extent of the illusion appears to differ between body regions. This study tested whether people experience tactile distance anisotropy on the lip. Participants were touched twice, once with the stimuli oriented across the width of the lower lip (i.e., the medio-lateral axis) and once with the stimuli oriented along the length of the lower lip (i.e., the proximo-distal axis). Participants made untimed judgments of whether the first or the second stimulus felt larger. The same experimental procedure was conducted on the dorsum of the hand. Our results show that a clear anisotropy was apparent on the hand dorsum, consistent with previous results; in contrast, no such effect was apparent on the lips. This study contributes to this area of research by providing further evidence of anisotropy in tactile distance perception on the dorsum of the hand. No evidence of anisotropy was found on the lips. Previous work has shown that anisotropies are either absent or much less in magnitude on body parts with glabrous skin, in contrast to those with hairy skin. Our findings lend further support to the differences in tactile distance anisotropies on hairy or glabrous skin. Additionally, findings may contribute to understanding body dysmorphia and its relevance to broader mental health outcomes.

20) Interactions between visual and proprioceptive perception: impact of sensory impairment

SARLEGNA Fabrice, ABI CHEBEL Najib Some blind individuals, such as famous artists Stevie Wonders or Ray Charles, exhibit extraordinary sensorimotor abilities, which may be specifically due to enhanced perceptual abilities. However, it remains unclear whether proprioception, the sense of body position and movement based on mechanoreceptors, is enhanced in blindness, as previously reported for touch or hearing. In fact, since the visual sense is thought to play a crucial role in calibrating spatial perception, and more specifically the proprioceptive sense, it is plausible that proprioception may be impaired in blindness. To directly test the competing hypotheses of cross-modal compensation versus general loss in sensory-impaired individuals, we assessed passive proprioceptive perception in blind and matched sighted blindfolded participants using an ipsilateral passive matching task. Results revealed that proprioception is most accurate in individuals who are considered legally blind but have some limited residual vision. Such supranormal proprioceptive acuity was found for the preferred and non-preferred arm, at the elbow and wrist joints. Surprisingly, we also found that metacognitive judgments of proprioceptive performance did not match actual performance. The finding that proprioception is supranormal in blind people with residual vision but not in totally blind people supports the idea that visual experience critically tunes proprioception and highlights the underappreciated role of residual vision in cross-modal plasticity. Moreover, the observed discrepancy between self-evaluated and actual performance leads to a new theoretical, four-layer model of proprioceptive function.

21) The connection between affective touch experiences during the lifespan and the modulation of interpersonal space in Anorexia Nervosa

L. Giraudo, E. Scaliti, F. Toppino, F. Bevione, M. Panero, G. Abbate-Daga, P. Longo1. Affective touch is a primary channel of social and emotional communication, highlighting the central role of the body in social relationships from the first years of life. Bodily experiences are pervasively altered in Anorexia Nervosa (AN): affective tactile stimuli are perceived as less pleasant in AN than in healthy controls (HCs), and interpersonal space (IPS) modulation is also disturbed.

We investigated the link between lifespan history of affective touch and IPS modulation in AN, comparing 76 patients with AN and 77 HCs. Participants completed self-report questionnaires, including the Tactile Biography Questionnaire assessing the quantity and quality of affective touch experienced across the lifespan, and then performed a computer-based task requiring to select their preferred social distance from approaching actors to index IPS.

Patients reported less affective touch during both childhood and adulthood, as well as lower comfort with affective touch, than HCs. In AN, a larger preferred distance in the IPS task was significantly associated with less affective touch and lower comfort with affective touch; no significant correlations emerged in HCs. In both groups, affective touch scores were not associated with explicit body-image–related symptoms.

These findings demonstrate a connection between early tactile interactions and IPS modulation in AN, underscoring the importance of implicit corporeality in social relationships. Accordingly, bodily experiences in AN should be considered beyond typical, explicitly reportable body-image symptoms.

22) Body-image misperception alters self-identity recognition in healthy individuals and patients with eating disorders: behavioral and neurophysiological evidence

M. Romeo, C. Zampese, M. Galigani, P. Longo, V. Lauro, A. Clocchiatti, V. Murtas, E. Ricciardi, G. Abbate-Daga, F. Garbarini Body-image misperception is a central feature in pathologies involving alteration of body-representation, as eating disorders (EDs). Nonetheless, healthy individuals may also exhibit a distorted perception of their own-body1. Here, we performed a systematic investigation of the link between body-misperception and self-identity recognition. To this aim, we exploited a visual-matching task designed to assess the well-known self-advantage effect2 (better performance in discriminating self- than other-body-parts in a visual-matching task) on both healthy controls (HC; n=50) and EDs patients (n=43). Participants were presented with images of self and stranger’s thighs either with real or perceived body-size (assessed with a body-size estimation task). Visual stimuli were presented in pair and subjects had to report whether stimuli were identical or different. We anticipated a modulation of the self-advantage effect due to a mismatch between real and perceived body-image.
Results of the body-size estimation task indicated that also HC exhibited body-misperception, despite a dramatic difference emerged between HC and EDs patients, with patients showing greater body-misperception than HC. As for the visual-matching task, we found a significant Scenario (real/perceived)*Identity (self/other)Body-Misperception interaction, with no Group (HC/EDs) effect, for both reaction-times (F1,63=14.887; p<0.001) and accuracies (F1,64=15.980; p<0.001). Crucially, in the real-scenario, participants of both groups at lower levels of body-misperception presented the typical self-advantage effect, with faster reaction times and greater accuracies for self- than other-body-images, while as the level of body-misperception increased, the self-advantage effect dissipated. Conversely, in the perceived-scenario, for both groups, the self-advantage effect was ever-present independent from the level of body-misperception. To investigate the electrophysiological correlates of such behavior, healthy women with high body-misperception (n=20) underwent the EEG version of the visual-matching task2. This protocol capitalizes on the mismatch detection mechanism, revealing greater N270 responses evoked by self-related stimulus changes. Electrophysiological results parallel behavioral findings, showing a significant ScenarioSequence interaction (F=8.62; p=0.006): mismatch detection responses emerged for perceived (p=0.002) but not real (p=0.213) self-body-images.
Our findings highlight the salience of perceived over actual body-image in driving implicit self-recognition. Notably, this modulation observed across clinical and non-clinical samples emphasizes the role of body-misperception as a transdiagnostic factor that shapes self-identity recognition mechanisms along a continuum from subclinical traits to full-blown EDs3. 23. Thaler, A., Geuss, M. N., Mölbert, S. C., Giel, K. E., Streuber, S., Romero, J., Black, M. J., & Mohler, B. J. (2018). Body size estimation of self and others in females varying in BMI. PLOS ONE, 13(2), e0192152. https://doi.org/10.1371/JOURNAL.PONE.0192152 24. Galigani, M., Ronga, I., Bruno, V., Castellani, N., Sebastiano, A. R., Fossataro, C., & Garbarini, F. (2021). Face-like configurations modulate electrophysiological mismatch responses. European Journal of Neuroscience, 53(6), 1869–1884. https://doi.org/10.1111/ejn.15088 25. Bourbeau, F., Bouchard, S., Corno, G., & Monthuy-Blanc, J. (2025). The Role of Body Image Perception on a Continuum from Dysfunctional to Healthy Eating Attitudes and Behaviors Among People Seeking Treatment. Journal of Clinical Medicine 2025, Vol. 14, Page 597, 14(2), 597. https://doi.org/10.3390/JCM14020597

23) Velocity-Dependent Pleasantness of Affective Touch in Anorexia Nervosa: The Inverted U-Shape May Not be the Predominant Fit

Sofia Tagini, Leonie Gaudinot, Giulia Chirchio, Valentina Villa, Gianluca Castelnuovo , Alessandro Mauro, Leonardo Mendolicchio, Federica Scarpina Previous research shows that tactile pleasantness depends on stroking velocity, with maximal pleasantness at speeds that optimally activate C-tactile afferents. At the group level, this produces an inverted U-shaped curve described by a negative quadratic function. Evidence suggests that this pattern may also emerge at the individual level and could potentially serve as a marker of mental health. Furthermore, higher interoceptive accuracy has been associated with a better quadratic fit. We investigated whether this pattern is present in individuals with anorexia nervosa (AN), a condition characterized by altered affective touch processing and interoception. Twenty-five women with AN and 25 female healthy controls rated pleasantness of brush stroking delivered at seven velocities (0.3–27 cm/s) on hairy (forearm, dorsal hand) and non-hairy (palm) skin. In both groups, at least half of participants showed neither a linear nor quadratic fit across velocities, indicating no systematic modulation of pleasantness by speed. For hairy skin, fitting profile differed significantly by group: individuals with AN more frequently exhibited a linear (44%) than quadratic (4%) pattern, whereas controls more often showed a quadratic (23%) than linear (14%) fit, in line with previous evidence. No group differences emerged for non-hairy skin; also, interoceptive accuracy was unrelated to individual fitting profiles. Although the prevalence of quadratic profiles was lower than previously reported, these preliminary findings suggest that in AN, pleasantness perception on hairy skin may be more accurately characterized by a linear rather than quadratic pattern. If replicated, individual response profiles to affective touch could contribute to the characterization of somatosensory-affective alterations in AN and inform the development of body-oriented or interoceptive-based therapeutic interventions.

24) Fast Periodic Visual Stimulation EEG unveils crossmodal interactions between somatosensory and visual body maps

G.A. Gambaretti, L. Cagliero, M. Galigani, B. Italia, M. Romeo, F. Garbarini The brain builds a coherent body representation by integrating multisensory information, in particular visual and somatosensory inputs1. Although relevant research suggests that visual and somatosensory body maps are functionally interconnected2, the nature of this interaction remains unclear. Here, we employed frequency-tagged EEG3 to investigate whether visually activating a body representation modulates somatosensory processing in two experiments. In the first, seventeen adults received periodic tactile stimulation either on the hand or the foot while simultaneously viewing images of hands or feet, all presented at 3Hz. This resulted in four experimental conditions where the visually-activated body map could either be congruent or incongruent with the somatosensory-activated body map. Crucially, when analyzing frequency-tagged responses over somatosensory regions at 3Hz, we found that neural responses differed according to the congruency between the visual- and tactile-activated body maps (Main Effect of Congruency: F1,17=15.340, p=0.002). In particular, we observed greater responses to tactile stimulation (irrespective of the tactile stimulated body-part) when visual stimuli activated a congruent body part, with responses to touch on the hand being higher when viewing images of hands compared to feet (p=0.038), and responses to touch on the foot being higher when viewing images of feet compared to hands (p=0.030).
In the second experiment, we aimed at addressing whether results provided by experiment 1 were primarily driven by congruency effects or whether brain activity was boosted by multisensory integration mechanisms, or rather by a combination of the two. Hence, we replicated the first experiment, and we also included unimodal conditions, in which only one body map at a time, either visual or somatosensory, was activated. Data collection of experiment 2 is still ongoing, but by the time of the conference preliminary results will be presented.
Our results of experiment 1 confirm the presence of cross-modal interactions between visual and somatosensory body maps. Furthermore, the validation of this paradigm, which has a high signal-to-noise ratio with a very short stimulus presentation, opens the way to explore the development of visual and somatosensory body maps in infants, providing evidence about when these maps emerge and how they interact during early typical and atypical development.

25. Blanke, O., Slater, M., & Serino, A. (2015). Behavioral, neural, and computational principles of bodily self-consciousness. Neuron, 88(1), 145-166.
26. Botvinick, M., & Cohen, J. (1998). Rubber hands ‘feel’ touch that eyes see. Nature, 391(6669), 756-756.
27. A. M. Norcia, L. Gregory Appelbaum, J. M. Ales, B. R. Cottereau, B. Rossion, The steady-state visual evoked potential in vision research: A review. J Vis 15, 4–4 (2015).

25) Listening to the gut: gastric interoceptive accuracy in blindness

A. Scarpellini, V. Domenici, G. Lettieri Interoception is the process by which the nervous system senses, interprets and integrates signals arising from within the body. While it plays a crucial role in emotional awareness and body representation (Khalsa et al., 2018), little is known about how it develops in the absence of vision. Recent findings suggest that visual experience significantly influences the bodily representation of emotions, with blind individuals placing less emphasis on the stomach area compared to sighted (Lettieri et al., 2024). However, it remains unclear whether these representational differences reflect altered perceptual sensitivity to visceral signals or a reorganization at a higher, conceptual level. To address this question, we will employ the Rumble Recognition Task, a novel paradigm assessing gastric interoceptive accuracy (Savage et al., 2025).
We will recruit early blind, late blind and sighted individuals. Following an overnight fast, participants will perform the Rumble Recognition Task in two conditions: fasted and after drinking 200ml of sparkling water. This two-interval forced-choice paradigm requires participants to discriminate real-time from pre-recorded gastric sounds streamed via a digital stethoscope. Additionally, subjective experience of hunger, nausea and disgust will be monitored before and after each experimental block. Gastrointestinal interoceptive accuracy will be quantified as the percentage of correct trials per block, while trial-by-trial confidence ratings will be used to assess interoceptive sensibility. Metacognitive insight will be estimated using receiver operating characteristic (ROC) curve analysis, examining the extent to which confidence predicts accuracy. We will test group differences in gastric interoceptive accuracy and metacognitive awareness, and explore whether the time spent without vision modulates these performances. Based on previously reported alterations in emotional body maps, we hypothesize that blind individuals will exhibit lower gastric accuracy and altered awareness compared to sighted controls. Furthermore, while sparkling water will enhance performance across all participants by increasing visceral signaling, it could potentially reveal group-specific modulation.
By directly linking sensory deprivation to gastric interoceptive accuracy, this study aims to clarify whether visual experience shapes the perceptual foundations of visceral awareness or primarily its representational mapping. These findings will advance our understanding of interoceptive plasticity and the multisensory construction of body representation.

26) Who am I? The relationship between body misperception and self-identity recognition in Borderline Personality Disorder

C. Zampese, L. Colle, C. Fossataro, I. Bucci, F. Garbarini, M. Romeo Identity disturbance, characterized by an unstable self-image or sense of self, is a key feature of Borderline Personality Disorder (BPD)1 and may include body-misperception phenomena, which can also be observed in healthy individuals (HC) in absence of any clinical diagnosis. Here, we investigated whether body-misperception impacts implicit bodily-self recognition by comparing BPD patients (n=21) with control participants (n=44). To this aim, we combined a body-size-estimation task2, that assesses individual levels of body-misperception, with a visual-matching task that measures implicit bodily-self recognition. In the latter, pairs of images depicting thighs belonging to either the self or a stranger were presented, and participants judged whether the stimuli were identical or different while ignoring the thighs’ identity. In this task, self-advantage should be described by faster and more accurate discrimination between same and different stimuli when self-thighs are included in the pair3. First, we expect levels of body misperception to be predicted by the clinical diagnosis. Second, we ask whether individual level of body-misperception interact with the possible presence of self-advantage, and if the clinical diagnosis modulates such interaction. Regarding the body-size-estimation task, BPD patients exhibited significantly greater body-misperception than HC (Mann-Whitney test: U=272; p=0.008). Concerning the visual-matching task, separate analyses of reaction times (RTs) and accuracy revealed, for both measures, a significant Identity (Self/Other)*Group (HC/BPD)*Body-Misperception interaction (RTs: F1,61=5.320; p=0.024; Accuracy: F1,61=4.128; p=0.047). Indeed, HC with low body-misperception exhibited the self-advantage effect, with faster RTs and higher accuracy for self- compared to other-body-images, whereas this effect was abolished at high levels of body-misperception. In contrast, BPD patients did not show a self-advantage effect regardless of body-misperception, with no differences in performance for self- and other-body-images.
These findings suggest that in healthy individuals body-misperception exerts a top-down modulation on bodily-self recognition, with alteration of the self-advantage effect when perceived and actual body-images do not match. Crucially, BPD psychopathology appears to disrupt the implicit bodily-self recognition mechanism independently of the presence of an altered body-image perception, as BPD patients failed to recognize themselves even at low levels of body-misperception. Despite an overall higher misperception in BPD, it does not account for impaired self-identity recognition, thus future studies can address other psychopathological features that might interfere with this mechanism.

REFERENCES: 30. American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.). https://doi.org/10.1176/appi.books.9780890425787 31. Romeo, M., Galigani, M., Zampese, C., Italia, B., Longo, P., Fossataro, C., Bruno, V., Lauro, V., Clocchiatti, A., Murtas, V., Ricciardi, E., Abbate-Daga, G., Garbarini, F. (2024) Dysmorphic perception of the body image modulates self-identity recognition: a behavioral and electrophysiological study. National Congress of Italian Society of Neuropsychology (SINP), 7-8 June 2024, Turin, Italy.
32. Galigani, M., Ronga, I., Fossataro, C., Bruno, V., Castellani, N., Sebastiano, A. R., … & Garbarini, F. (2021). Like the back of my hand: Visual ERPs reveal a specific change detection mechanism for the bodily self. Cortex, 134, 239-252.”

27) The dynamics of bodily self-exploration in early life: a kinematic study in newborns

L. Cagliero, A. Rossi Sebastiano, B. Italia, E. Frisenna, M. Hoffmann, J. Khoury, F. Gama, G. Borini, G. Serra, C. Peila, A. Coscia, F. Garbarini Early self-exploratory movements have been hypothesized to play a fundamental role in shaping a primitive bodily self-representation, as embodied sensorimotor experience may enable intermodal perception even in utero. Consistent with the involvement of self-exploration in the emergence of body representation, observations of freely moving newborns suggest that the most frequent spontaneous movements are directed toward the body (e.g., hand-to-face or hand-to-trunk contacts). To provide quantitative evidence for this qualitative observation, the present study systematically characterizes the kinematic profile of spontaneous movements in newborns (N=24; 12-72 hours old) by combining video recordings in an ecological setting and automatic-tracking techniques using computer-vision algorithms.
Neonatal hand movements were classified into 4 categories: toward the mouth, toward the head, toward the trunk (i.e., self-directed) and toward the external environment (i.e., externally-directed). Our results provide the first quantitative evidence that newborns engage significantly more in self- than externally-directed movements (W=281, p< .001), with the trunk being the most frequently targeted body area, followed by the head and the mouth (.2 =21.6, p< .001). Preliminary analyses on the velocity profiles suggest greater deceleration in self- than externally-directed trials as the movement unfolds (t= -9.11, p< .001). Interestingly, the velocity of self-directed movements appears to be modulated by the targeted body area, with movements targeting more delicate regions (such as the head and mouth) being slower compared to hand-to-trunk movements. This may suggest that newborns could predict the sensory consequences of their own movements and try to avoid overly forceful contacts, possibly indicating that self-directed movements occur under a certain degree of motor control. We interpret these findings as endorsing self-directed behaviour as a crucial context fostering the emergence of an early bodily-self representation in typical development. By combining semi-automatic kinematic scoring with body-pose estimation models, our results contribute to the characterization of spontaneous motor repertoire in typical development, thus laying the groundwork for investigating its possible alteration in neurodevelopmental disorders.

28) Researching Body Perception: Toward an Integration of Quantitative and Qualitative Interdisciplinary Approaches to Address the Multiplicity of Bodily Experiences

Roel Lesur, M., Turmo Vidal, L., Longo, M. R., Slatman, J., Väljamäe, A., & Tajadura-Jimenez, A. Distortions in bodily self-perception are a core feature of multiple psychiatric and neurological conditions, yet progress in this field continues to be constrained by persistent challenges, including construct ambiguity, dissociations between measurement tools, and loss of experiential nuance in empirical reports. In our recently published work, we argue that advancing the study of bodily self-perception and its disturbances requires a more integrated mixed-methods approach, particularly in light of the rapid expansion of experimental paradigms and technologies targeting bodily experience.

Our work highlights how commonly used measures, ranging from behavioral estimation tasks and psychophysiological indices to neuroimaging, often capture distinct and sometimes non-overlapping aspects of bodily self-perception. While these tools have generated valuable mechanistic insights, their isolated use risks oversimplifying complex bodily phenomena and obscuring meaningful individual differences.

To address these limitations, we propose an integrative framework that systematically combines quantitative methods with qualitative and experiential approaches. Specifically, our work provides a survey of qualitative design research methods and illustrates how they can support three key stages of the research process: (i) experimental design, by informing task construction, experimental apparatus and stimuli, and construct operationalization; (ii) data collection, through the inclusion of qualitative methods from design-research that might capture individual differences and experiential nuance; and (iii) data analysis, by combining mixed outcomes and potentially revealing dimensions of bodily experience that may otherwise remain unnoticed.

This mixed-methods approach is particularly relevant for psychiatric and neurological conditions in which altered body perception cannot be fully characterized by performance metrics alone. By preserving experiential nuance while maintaining rigor, generalizability, and replicability, our work addresses well-recognized pitfalls in the field and offers a timely roadmap for advancing theory, methodology, and clinical relevance in a rapidly growing interdisciplinary field.

29) Self-touch enhances bodily self-referential processing through alpha-band sensory gating: an EEG study

B.Italia, C. Zampese, C. Tavazzi, A. Rossi Sebastiano, C. Fossataro, F. Garbarini, V. Bruno “Introduction Traditionally used across different cultures and spiritual practices, self-touch is an instinctual gesture generally associated with enhanced attention to internal bodily states. Beyond these contexts, the instinctive nature of bringing one’s hands into contact with the body emerges early in development and persists into adulthood, manifesting spontaneously during emotional regulation.. Previous behavioural data from our lab. demonstrated that self-touch enhances interoceptive accuracy while diminishing the perception of external stimuli, suggesting a shift in attentional weighting toward the bodily self. Here, we aim to identify the electrophysiological correlates of this modulation by testing whether and how self-touch modulates alpha-band power, a neural marker of self-referential processing. and sensory gating.. Methods: Eighteen healthy participants underwent 5-minute resting-state EEG recordings before and after two 10-minute postural manipulations where the right hand was in contact with the left hand (self-touch condition) or with an object (object-touch condition). We analysed the data using a data-driven non-parametric clustering approach. to compare, for each condition, the differences between pre vs. post manipulation without a priori assumptions. Results: Our results show that self-touch significantly modulates alpha-band power. Specifically, alpha power increased significantly from pre- to post-postural manipulation only in the self-touch condition, appearing in a large bilateral frontocentroparietal cluster (p = 0.018). Conversely, no significant pre vs. post changes were observed in the object-touch condition. Discussion: These results converge with our previous behavioural data and provide electrophysiological support for a modulation of sensory processing during self-touch. The observed alpha power increase is consistent with a functional reweighting of sensory signals, favouring internal and self-related inputs over exteroceptive information. This mechanism seems to reflect a dynamic shift in salience, where the internal bodily states become the primary focus of neural processing while external inputs are down-weighted. In line with the role of alpha oscillations in sensory gating., self-touch appears to facilitate a transition from an exteroceptive focus toward a more interoceptive and self-oriented state. Such a reconfiguration of sensory priorities not only may help explain the spontaneous use of self-touch during stress regulation, but also suggests its potential relevance for clinical conditions characterized by altered body representation or disrupted self-referential processing.

References: 1. Gibson, J. (2019). Mindfulness, interoception, and the body: A contemporary perspective. Frontiers in psychology, 10, 475917. 36. B. Italia, A. Rossi Sebastiano, C. Zampese, C. Fossataro, I. Ronga, F. Garbarini, and V. Bruno, “The influence of self-touch on perceptual sensitivity: diametrical modulation between interoceptive and exteroceptive perception.,” 2024. 37. Knyazev, G. G. (2013). EEG correlates of self-referential processing. Frontiers in human neuroscience, 7, 264. 38. Klimesch, W., Sauseng, P., & Hanslmayr, S. (2007). EEG alpha oscillations: the inhibition–timing hypothesis. Brain research reviews, 53(1), 63-88. 39. Maris, E., & Oostenveld, R. (2007). Nonparametric statistical testing of EEG-and MEG-data. Journal of neuroscience methods, 164(1), 177-190.

30) Neural Signatures of Body-Driven Conflict in Anorexia Nervosa

R.C. Lima, G. Fusco, G. Vercelli, I. Bufalari

Conflict and error monitoring are crucial for cognitive control and might result impaired in psychiatric disorders, including Anorexia Nervosa (AN). Indeed, individuals suffering from AN can show impairments in processing conflicting body-related representations and adapting behavioural adjustments following errors. Although recent studies suggest that patients with AN are emotionally and perceptually sensitive to the processing of body-related stimuli, the neurophysiological mechanisms underlying their performance monitoring remain underexplored. The N2, error-related negativity (ERN), and mid-frontal theta activity (MF.) are key electrocortical markers of conflict and error processing. While recent evidence indicates altered patterns of these signals during the processing of neutral conflicts (i.e., letters), it remains unclear whether encoding of conflicting body-related stimuli is also affected by the body representation distortion that characterizes AN symptomatology. This study investigates the neural signatures of performance monitoring in AN by examining both event-related potentials and oscillatory activity during exposure to conflicting body stimuli. The results may provide novel insights into the neurocognitive mechanisms underlying body representation in AN, with potential therapeutic implications.
We are recruiting 24 female AN patients and 24 healthy controls (HC). Participants will complete a Body-Flanker task, involving congruent and incongruent trials, with underweight and overweight body silhouettes presented in both upright and inverted orientations. EEG will be recorded using a 64-channel system, and neural data will be analysed in the time domain (amplitude/latency) and frequency domain (theta power). Behavioural measures (reaction time, accuracy, and performance index) and neural indices (N2, ERN, mid-frontal theta power, and other potentials indexing body-related perceptual processing) will be subjected to 2.2.2 mixed ANOVAs with factors: Group (AN, HC), Orientation (Upright, Inverted), and Congruency (Congruent, Incongruent). Additionally, EEG and behavioural measures will be correlated with psychometric scores from psychiatric assessments. We hypothesize impaired performance monitoring and altered neural responses to conflicting body stimuli in AN patients.

31) The Interplay Between Heartbeat-Evoked Potentials and Neuropsychiatric Dimensions using the Hierarchical Taxonomy of Psychopathology

C. Campos, C. Botelho, P. Braga, I. Macedo, T. Paiva & R. Pasion

Heartbeat-evoked potentials (HEP) are electrophysiological markers of cortical responses to cardiac signals and constitute a non-invasive index of interoceptive processing. Growing evidence suggests that altered interoception is implicated in multiple neuropsychiatric conditions; however, most studies rely on categorical diagnostic frameworks, limiting the ability to capture shared and distinct mechanisms across psychopathology dimensions. The present study aims to examine associations between HEP metrics and dimensional psychopathological expressions as conceptualized in the Hierarchical Taxonomy of Psychopathology (HiTOP) in order to evaluate their possible transdiagnostic value. A community-based sample is currently being recruited (31 completed; target N = 200), with minimal exclusion criteria employed to capture a broad range of symptom presentations and severity levels, thereby adequately representing the natural variability and complex structure of psychopathology. Participants will complete the HiTOP Self-Report measure, a comprehensive 400-item questionnaire that captures the dimensional and hierarchical structure of psychopathology. Specific scores will be computed for each spectrum (internalizing, externalizing, thought disorder, detachment, and somatoform) and each subfactor (fear, distress, mania, eating pathology, antisocial behavior, and substance use). Simultaneous electroencephalography (64 channels) and electrocardiography recordings will be conducted to extract HEP. Recordings will take place during resting-state conditions (eyes open and closed) and during a modified Heartbeat Attention Task, which includes interoceptive versus exteroceptive attention blocks designed to modulate HEP amplitude. A cluster-based permutation approach will be applied to identify the time-window and electrode sites of interest for HEP amplitude extraction. Trait-level interoceptive differences will be measured using self-report questionnaires (Interoceptive Attention and Accuracy Scales). To examine the association between HEP and psychopathology, second-order hierarchical structural equation models will be employed with theory-driven loadings between subfactors, spectra, and a higher-order general factor. HEP metrics will then be examined through a series of regressions: (i) regressing HEP on the general factor; (ii) evaluating whether spectra account for additional variance beyond the general factor; (iii) within each spectrum, assessing whether subfactors explain unique variance beyond their parent spectrum. This sequential modeling strategy partitions variance in a theory-consistent manner and enables us to determine whether altered cortical processing of cardiac signals reflects a transdiagnostic general liability, broader spectrum-level processes, or more specific subfactor-level variations in psychopathology.

32) Motor dynamics during infectious threats perception: postural freezing and corticospinal excitability

G. Guerra Frey, M. Born, A. Serino

The brain can detect infectious threats before physical contact, recruiting the peripersonal space (PPS) to coordinate defensive and immune-related responses. Behavioral evidence shows a distance-dependent freezing response, characterized by reduced body sway when infectious virtual avatars approach. Moreover, this effect is modulated by disgust sensitivity, a core component of the behavioral immune system, with lower sensitivity associated with greater postural immobility. Here, we examine the neural correlates of this behavioral phenomenon using Transcranial Magnetic Stimulation (TMS). In addition, we explore whether freezing reflects a generalized suppression of corticospinal excitability or a controlled motor state combining global immobility with effector-specific readiness. Corticospinal excitability is assessed using single-pulse TMS over the left primary motor cortex (M1) at five temporal delays (D1–D5) while neutral or infected avatars approach. MEPs are recorded from the right first dorsal interosseous (FDI) as the primary target and from the right anterior deltoid (AD) to monitor postural engagement. MEP modulation index (MEPi) is calculated as the ratio between condition and baseline MEPs and is used to compare experimental conditions. The same index is applied to AD using the area-under-the-curve method to capture postural effects. We predict that FDI excitability will show greater overall amplitude and distance-dependent MEPi modulation during infectious trials, paralleling behavioral freezing. AD MEPi is expected to increase at closer distances, reflecting active postural engagement rather than motor inhibition. These effects may further vary as a function of individual differences in disgust sensitivity.

Together, these behavioral and TMS findings are revealing that peripersonal space functions as a multi-level predictive system, implementing both motor and immune preventive mechanisms to guide defensive interactions with potential threats.

33) Investigating sensory processing and body perception disturbances in depressive symptomatology through the auditory-driven Footsteps Illusion

I.Fernández Vallejo, B. Lenggenhager, J. López Castroman, M.M. Borda Mas, M.L. Avargues Navarro , A. Alacreu Crespo, A. Tajadura-Jiménez.

Depressive symptomatology (DS) is associated with disturbances in body perception and emotional experience, with increased perceived heaviness and affective depletion closely linked to symptom severity. Body perception is not fixed but dynamically updated through multisensory integration. While prior research suggests that disruptions in sensory processing and sensorimotor integration can influence DS and treatment response, the role of exteroceptive sensory signals in shaping body perception among individuals with DS remains unclear. Moreover, existing studies examining the relationship between DS, sensory processing, and body perception disturbances are limited and fragmented.
In this study, we used the Footsteps Illusion, relying on auditory (exteroceptive) signals, to examine whether sensory integration mechanisms underlying body perception are altered in individuals with DS. Participants’ footstep sounds were filtered to simulate lighter or heavier bodies, using high- and low-frequency filters shown to influence perceived body weight, physical effort, and affect. Participants were separated in DS or healthy controls ) based on self-reported DS (QIDS questionnaire and interview). They performed walking exercises under three sound conditions: unaltered, high-frequency, and low-frequency filtered footsteps sounds. Effects on body perception and emotional state were assessed using self-report, body-visualization, behavioural (gait), and physiological measures. Sensory sensitivity, interoceptive processing, baseline emotional state, and body perception were also assessed to characterize both populations.
Results confirmed group differences in baseline emotional valence, with DS participants reporting greater sadness than controls. QIDS scores were negatively correlated with emotional valence at baseline and in the ‘heavy’ footsteps condition (low frequency), indicating that higher depressive symptomatology was associated with more negative affect. Critically, DS participants showed an atypical response to the ‘light’ footsteps condition (high frequency), reporting increased perceived heaviness. Correlations between QIDS scores and body-related sensations, particularly in the high-frequency condition, further suggest that depressive severity is associated with altered body perception. These findings indicate potential disruptions in sensory integration mechanisms in DS, whereby altered auditory feedback differentially modulates body perception. We will also discuss differences in interoceptive abilities and sensory hypersensitivity between DS and HC.
These findings suggest that body perception remains malleable in DS, and highlight opportunities for wearable sonification technologies in DS assessment and intervention.

34) Respect My Space: Investigating Interpersonal Space and Multisensory Integration with Autistic and Social Anxiety Traits Using fNIRS.

L. M. Dodd, M. L. Filippetti, S. Rigato

How close is too close? Everyday social interactions depend on interpersonal space (IPS), i.e., the social distance maintained between individuals. IPS is sensitive to social cooperation and interaction, and shaped by the integration of sensory, bodily, and social cues. Research suggests that both autistic and social anxiety-related processes may contribute to IPS differences. For example, autistic individuals show reduced flexibility and tendencies to either violate others’ IPS or maintain larger distances, whereas social anxiety traits have been associated with larger IPS. However, research has used unimodal stimuli and behavioural measures alone, and little is known about how visual and auditory approach cues jointly shape IPS boundaries and differences in neural correlates. By examining how multisensory signals shape IPS, this research investigates neural representations of self-other boundaries, and how these are modulated by autistic and social anxiety traits. Adult participants viewed short video clips depicting a stranger approaching from a first-person perspective. The task used a multisensory design with three conditions: 1) visual (observing the approaching individual); 2) auditory (hearing footsteps that increased in perceived distance); 3) audiovisual (combining both cues). To provide an index of IPS boundaries, participants were asked to press a button when they began to feel uncomfortable as the stranger approached. A linear mixed model on preliminary behavioural data (N = 27) showed that visual and audiovisual conditions were associated with larger IPS boundaries than auditory conditions, with the greatest distance in audiovisual condition. Higher social anxiety traits predicted larger IPS boundaries in audiovisual relative to auditory conditions, whereas higher autistic traits were linked to smaller IPS boundaries in visual versus auditory conditions, with a non-significant trend in audiovisual trials. Together these findings suggest that multisensory social cues differentially modulate IPS as a function of autistic and social anxiety traits, highlighting distinct mechanisms underlying the regulation of self-other boundaries.

35) Reduced affective touch sensitivity in depersonalisation and the influence of respiratory phase

V. Alekseeva, L. Crucianelli, F. Meconi
Introduction: Depersonalisation is characterised by a diminished sense of self, involving detachment from one’s body, emotions and actions, such that experiences are perceived not from within oneself, but as if from an external observer perspective. Selfhood, however, is not purely private; through skin-to-skin contact, the bodily self and its boundaries are constructed in relation to others. Depersonalisation may therefore reflect a decoupling not only from the self but also from others, potentially involving disturbances in processing socially meaningful affective interoceptive cues. Affective touch, a slow gentle stroking, activates C-tactile (CT) afferents and is typically experienced as more pleasant than faster CT-non-optimal stroking. The perceived difference in pleasantness between CT-optimal and CT-non-optimal touch (affective touch sensitivity) represents an affective interoceptive sub-modality linked to bodily self-awareness. While reduced affective touch sensitivity was reported in conditions involving bodily self disturbances, for depersonalisation it remains unknown. Rhythmic interoceptive signals were proposed to support a stable sense of self through dynamic coupling with external sensory signals. Among bodily rhythms, respiration was shown to have phase-specific modulation of tactile perception and interoceptive processing. In our previous work, we showed that respiration shapes affective touch perception. Methods: 29 (out of 36 planned) young adults were pre-screened using the Cambridge Depersonalisation Scale and assigned to High-DP or Low-DP groups (cut-offs ≥70 and ≤20). Participants then followed auditory breathing instructions and received CT-optimal and CT-non-optimal stroking on the forearm during inhalation and exhalation. After each stroke, participants rated touch pleasantness on a 1–100 scale. Results: Preliminary results from a mixed 2.2 ANOVA showed that Low-DP participants rated CT-optimal touch as significantly more pleasant than non-CT-optimal touch, whereas this differentiation was not observed in High-DP participants, indicating reduced affective touch sensitivity in the High-DP group. Respiratory phase did not significantly modulate ATS overall. However, planned analyses showed that the difference in ATS between groups was significant during inhalation but not during exhalation. Discussion: These findings show reduced affective interoceptive differentiation in depersonalisation and highlight affective touch sensitivity as a potential behavioural marker of altered bodily self-processing. Respiration may represent a potential target for modulating affective touch sensitivity in depersonalisation.

References: 46. Alekseeva, V., & Ciaunica, A. (2025). It Is Movement All the Way Down: Broken Rhythms and Embodied Selfhood in Depersonalization. Behavioral Sciences, 15(8), 1090. https://doi.org/10.3390/bs15081090 47. Crucianelli, L., Demartini, B., Goeta, D., Nisticò, V., Saramandi, A., Bertelli, S., Todisco, P., Gambini, O., & Fotopoulou, A. (2021). The Anticipation and Perception of Affective Touch in Women with and Recovered from Anorexia Nervosa. Neuroscience, 464, 143–155. https://doi.org/10.1016/j.neuroscience.2020.09.013 48. della Penna, F., Zaccaro, A., Bayram, B., Bubbico, F., Perrucci, M. G., Costantini, M., & Ferri, F. (2025). Breathing strategies to influence perception: Evidence for interoceptive and exteroceptive active sensing [Preprint]. bioRxiv. https://doi.org/10.1101/2025.05.15.654033 49. Sierra, M., & Berrios, G. E. (1998). Depersonalization: neurobiological perspectives. Biological psychiatry, 44(9), 898–908. https://doi.org/10.1016/s0006-3223(98)00015-8 50. Alekseeva, V., Crucianelli, L., & Meconi, F. (2026). Respiratory phase modulates sensitivity to affective touch. Manuscript submitted for publication.”

36) Inverse MDS: From the Rubber Hand Illusion to the Latent Structure of Bodily Space

P. Luszuk, P. Litwin, K. Kubik, M. Longo

Both the phenomenology and the strength of body-ownership illusions (e.g., the rubber hand illusion, RHI) depend on specific experimental conditions. Commonly used measures may have limited sensitivity to subtle qualitative differences between bodily illusions. Inverse multidimensional scaling (inverse MDS) has been recently demonstrated to be an effective method for measuring the strength of the RHI. This method might circumvent the methodological limitations of Likert-scale questionnaires and be sensitive enough to measure the strength of different body ownership illusions in detail.
This poster will present the most recent findings on the potential of inverse MDS to reveal the latent psychological space of bodily experiences, which can enhance our understanding of the distinct experiences associated with different body-ownership illusions. The previous study consisted of two experiments, in which participants experienced the RHI in synchronous and asynchronous conditions as well as the RHI and the arm immobilization imaginative suggestion. In each condition, participants repeatedly arranged items related to distinct bodily experiences in accordance with the perceived similarity between them. Proximity data obtained from the arrangements were represented as distances in a multidimensional bodily space. To measure RHI strength, we focused on distances between items representing experimental conditions and two baseline items representing cases of no ownership over an external object and normal bodily feelings. We found that the distance between the rubber hand and an external object was significantly larger in the synchronous than the asynchronous condition, and larger than the distance between the immobilized arm and the normal body, demonstrating stronger shifts in ownership for synchronous RHI.
The study also provided novel insights into the structure of mental bodily space representation, which reliably included two dimensions related to independent aspects of bodily experiences (Embodiment and Stimulation) as well as three distinct qualitative clusters (De-embodiment, Artificial Stimulation, and Normal Bodily Feelings).
The currently conducted study aims to examine how a substantial increase in the number of items representing distinct bodily experiences affects the structure of the bodily space identified in previous research. This study will rely on an online inverse MDS arrangement task, which may provide a feasible and practical solution for scaling up this approach in future research.

37) Appearance vs Capability: How Age Shapes Body Satisfaction During Pregnancy

Katie Bryant & Kirsten McKenzie

Body image typically improves with age; research consistently links increasing age to greater body acceptance and lower body dissatisfaction. At the same time, the age at which people become first-time parents is rising in many countries, with pregnancies over age 35 becoming increasingly common. Pregnancy, however, represents a unique period of rapid and highly visible bodily change, during which social expectations and medical discourse may shape body image in ways that differ from patterns observed outside of pregnancy. Despite these dynamics, relatively little research has examined how age influences body satisfaction during first-time pregnancies. Furthermore, much of the existing literature has focused primarily on body dissatisfaction or weight concerns, often without distinguishing between related but distinct constructs such as body satisfaction, positive body image and self-esteem. The current mixed-methods study, therefore, examined how age at first pregnancy relates to body satisfaction, positive body image, negative body image and self-esteem. Despite limited statistical power, older participants reported significantly higher body satisfaction during pregnancy than the youngest group. Notably, pregnancy-specific body satisfaction did not correlate with measures of positive body image, negative appearance evaluation, or self-esteem, suggesting that body satisfaction during pregnancy may operate independently from broader body image and self-evaluative constructs. Qualitative findings also revealed clear age-related patterns; younger participants reported difficulty accepting bodily changes and often focused on features such as the bump and stretch marks, using descriptors such as “fat” or “large.” In contrast, older participants described feelings of empowerment, enjoyment, and confidence, emphasising bodily capability and the experience of pregnancy itself, with descriptors including “beautiful,” “confident,” and “proud.” Across age groups, approximately half of participants felt their age had influenced their body image during pregnancy. Younger participants attributed this to social media expectations, whereas older participants described factors such as increased self-compassion, pride, and gratitude. Together, these findings suggest that first-time pregnancy experiences differ by age, with older participants reporting greater body satisfaction and a shift from appearance-focused concerns toward embodied empowerment. This study highlights the value of integrating quantitative and qualitative approaches to better understand body image during pregnancy and underscores the need for age-sensitive antenatal support.

38) Three Trainable Components of Body Representation: Evidence from a Decade of Naturalistic Perceptual Skills Training

K Shcherbakova

Background. Body awareness frameworks developed for clinical and well-being contexts (e.g., Mehling et al., 2009) predominantly assess interoceptive awareness (Price et al., 2018) and its relationship to stress and emotional regulation. While valuable for therapeutic applications, these frameworks conflate dimensions of body representation that are functionally and neurally distinct, and do not address somatosensory discrimination capacities relevant to motor learning. We propose a complementary framework grounded in movement pedagogy, identifying three trainable components of body representation with distinct neural substrates.

Methods. The proposed framework was developed from the naturalistic study of Baseworks — a movement methodology that underwent approximately ten years of iterative refinement in a studio context with over 10,000 learners across diverse populations, optimizing for a single constraint: communicability — the reliability with which movement instructions produce the intended movement in a diverse learner. Systematic observation, textual analysis of movement instructions, and learner feedback (n=61 text-based; n=25 interviews) were used to formalize the resulting framework.

Findings. Communicability failures consistently clustered around three separable perceptual bottlenecks, each addressed by a distinct set of training principles. (1) Localized proprioceptive awareness — conscious detection of spatially specific sensations arising from muscle activation, hypothesized to reflect fusimotor reafference (Luu et al., 2011); large individual variation was confirmed in a survey of non-practitioners (n=36). (2) Spatial awareness — the capacity to encode, maintain, and reproduce body configurations without visual feedback, mapping onto the central memory mechanism recently identified in repositioning tasks (Proske & Weber, 2026) rather than peripheral spindle-mediated position sense; predictable failure patterns in naive learners suggest this is systematically undertrained in healthy populations. (3) Interoceptive awareness — self-regulatory monitoring of breathing and load, supporting conditions for sensory discrimination in our framework. Structured training addressing each bottleneck produced reported and observable improvements across all three dimensions.

Implications. In clinical populations, body representation breaks down through damage or disorder. In healthy but untrained populations, it is not broken — it is underdeveloped, in ways that are invisible until a training context makes the failure legible. We propose that these three components are experimentally dissociable, differentially trainable, and collectively constitute a more actionable model of body representation for research in healthy populations and potential clinical translation.

39) A systematic review and meta-analysis of cardiac interoceptive accuracy in anorexia nervosa

C. Gend, L. Remy, A. Lutz Objective: Interoceptive impairments have been suggested as an etiological factor in anorexia nervosa (AN) but have not been consistently confirmed across interoceptive dimensions and bodily systems. This systematic review and meta-analysis provides a focused investigation of cardiac interoceptive accuracy (IAcc) in AN. We examined whether individuals with AN show reduced cardiac IAcc compared to healthy controls (HC) and whether this difference is moderated by age, sex, task type, guessing instructions, illness duration, or study quality. Method: A systematic literature search was conducted in the databases PsycINFO, PubMed, MEDLINE, Web of Science, and relevant journals. Studies measuring heartbeat perception using behavioral tasks in patients with AN and HC were included. Standardized mean differences were compared between groups using a random-effects model. Results: A meta-analysis with 16 studies revealed no significant difference in cardiac IAcc between individuals with AN and HC. Only illness duration emerged as a significant moderator, with lower IAcc in samples with shorter illness duration. Discussion: The findings do not confirm consistently reduced cardiac IAcc in AN. Cardiac IAcc may change over the course of illness, with deficits potentially limited to the early stages. A major limitation of the literature concerns the almost exclusive reliance on the heartbeat counting task, the validity of which has been questioned. Future research should develop and employ alternative tasks, consider a broader conceptualization of interoception, across dimensions and bodily systems, and include longitudinal investigations.

40) Reaching Space: Sensory and Environmental Effects

D. Fray, P. Caggiano Action in the environment requires accurate mental representations of the surrounding space. Previous research has demonstrated the plasticity of such a space through task demands and internal mental representations of the body. However, studies have typically examined a unidirectional linear assessment of the peri-personal space directly in front of the individual. This exploratory study examined a volumetric area of perceived maximum reachable space across multiple experimental conditions. In doing so, it attempted to isolate the role of visual and proprioceptive self-related sensory feedback for these distance estimations, whilst also accounting for the possible effects the direction of travel a target may have on this perception of space. There were significant overestimations of reach when compared to baseline, particularly when participants were relying upon solely visual information. In three-dimensional space, lower targets were significantly over estimated, which also interacted with the other experimental conditions. These findings highlight the implicit and critical role proprioceptive information has in action and the representations of space around the individual.

41) The Active Self in Autism: Insights from Multisensory and Sensorimotor Processes

A.Jahanian-Najafabadi, A.Rastegari The active self, defined as the embodied sense of self arising from goal-directed actions and interactions with the environment, is fundamentally supported by dynamic sensorimotor processes, particularly multisensory integration and proprioception. Atypical self-representation in individuals with Autism Spectrum Disorder (ASD) has been proposed to result from disruptions in these foundational processes, which are often monitored implicitly. To advance theoretical and clinical understanding, we conducted a systematic review of 37 empirical studies published between 2010 and May 2025 that examined the bodily and multisensory components of the active self in ASD. We focused on constructs such as body ownership, sense of agency, and peripersonal space. Findings were synthesized around three central themes: (1) multisensory integration, (2) self-bias and self-other differentiation, and (3) motor contributions to bodily awareness. Our analysis indicates consistent atypicalities in multisensory integration and body representation in ASD. These often manifest as reduced susceptibility to embodiment illusions, such as the rubber hand illusion, and a heightened, inflexible reliance on proprioceptive input. This pattern suggests a rigidly defined embodied self and a steeper self-to-other representational gradient. Evidence of altered prospective motor planning and execution further supports the view that predictive processing is disrupted in ASD. By integrating research from sensorimotor control, cognitive neuroscience, and clinical psychology, this systematic review demonstrates that atypical sensory processing is a core contributor to the development of a less coherent active self in ASD.

We conclude by identifying critical gaps in the literature, including the need for large-scale studies in autistic adults and longitudinal research designs. Finally, we propose future directions for research aimed at developing interventions informed by embodiment, targeting multisensory integration recalibration, and enhancing body awareness.

42) Embodied Time: Does an Illusory Stretch of the Hand Affect Tactile Temporal Order Judgments

O. Wódecka, K. Overvliet, A. Keizer, C. Dijkerman Humans experience time, despite not having a dedicated sensory organ for it (Wittmann, 2009). Our temporal perception can be very good, but it is still subjective and influenced by many factors, such as cognition (Matthews & Meck, 2016). Body perception is often overlooked as a possible influence, even though it is known that many sensory bodily signals (e.g. heartbeat) have a temporal component (Wittmann, 2009) and that body perception affects many cognitive processes (Dijkerman & Lenggenhager, 2018). Therefore, there is a possibility that the way time is experienced is affected by body perception. The current experiment aimed to examine whether changing perceived hand size influences performance on a temporal order judgment (TOJ) task. The appearance of the participants’ hand was altered to look longer in the MIRAGE, a multisensory hand-illusion set-up, while simultaneously gently pulling the finger of the hand to give a feeling of a “stretching finger”. The hand was “stretched” to various extends across conditions. The TOJ task consisted of two sequential tactile stimuli (short taps) on the base and tip of the underside of the index finger. Based on previous findings, it was expected to observe an improvement in performance on the TOJ task when the finger appeared lengthened. However, the current study does not show support for this hypothesis as no significant difference in TOJ performance was found between conditions. Plausible reasons for the findings are discussed.

43) Feeling (dis)connected to the self and others: evidence from a virtual-reality Cyberball paradigm in young adolescents

I. Guglielminetti, L. Della Longa, I. Valori, T. Farroni Introduction What becomes of the self when social recognition fails and one’s presence goes unnoticed by others? During adolescence, peer relationships take on a privileged role in everyday life and, within a phase of profound bodily and psychological changes, may significantly shape socio-emotional development. At this time, losing a sense of connection between the self and others can carry negative affective and physiological consequences, potentially altering how adolescents experience themselves and the surrounding world. From this perspective, emotion regulation and Self experience are closely intertwined, as both emerge in a relational context and depend on the dynamic integration of interoceptive (internal states) and exteroceptive (environmental and social cue) information. In the context of social exclusion, interpersonal tactile interactions can be considered as a potential bridge to restore a sense of connection with the self and with others, promoting bodily awareness and mitigating the effects of exclusion.

Method In the present study, young adolescents (N = 67; aged 10-14 years) were exposed to a social exclusion paradigm (Cyberball) implemented in an immersive virtual environment (IVR). After the exclusion phase, while participants remained immersed in IVR, they received externally delivered sensory stimulation, manipulated between groups (touch vs. auditory input). Cardiac activity was continuously monitored via ECG to derive heart rate (HR) and heart rate variability (HRV) across the experiment.

Results Social exclusion led to a significant reduction in subjective valence, although it was not accompanied by the expected cardiac responses. Crucially, affective touch —unlike auditory stimulation— restored valence to baseline levels and reduced perceived arousal. Consistently, affective touch elicited a more pronounced reduction in HR compared with auditory input, while both sensory stimuli were associated with increased HRV. Moreover, loneliness moderated these effects: high-loneliness adolescents showed greater emotional and physiological sensitivity to sensory cues, with increased valence, decreased arousal, and reduced HR following affective touch; in contrast, auditory stimulation elicited the opposite pattern.

Discussion In conclusion, interpersonal touch may support affective recovery and regulatory processes by enhancing attention to body-related interoceptive signals. These effects were moderated by loneliness, suggesting that tactile stimulation may be particularly relevant for adolescents with greater socio-emotional vulnerability.

44) Body ownership in somatic symptom disorder

K.J. van der Boom, A. Keizer, J.J. van Grondel, R. Geenen, H.C. Dijkerman Introduction Persistent physical symptoms are associated with multiple biological and psychosocial contributing mechanisms. A sparsely considered, but possibly relevant factor concerns body representation distortions. The aim of this study was to examine differences in the sense of body ownership in patients with somatic symptom disorder (SSD).

Methods Participants with SSD (n = 28) and matched healthy controls (n = 26) were subjected to the rubber hand illusion (RHI) (Botvinick & Cohen, 1998). The (visible) rubber hand and the (invisible) participant’s real hand were stroked in a synchronous (illusion) and asynchronous (control) condition for 60 seconds. The experience of body ownership was assessed by an objective measure, proprioceptive drift (shifting of the felt location of the real hand towards the rubber hand) and a subjective measure, the Embodiment Scale. This measure contains three subscales, Embodiment (of rubber hand), Disembodiment (of real hand) and Physical Sensations (Romano et al., 2021).

Results Preliminary analyses showed no significant difference between patients and controls on proprioceptive drift in either the synchronous or asynchronous condition. The two groups also did not differ in the embodiment of the rubber hand in either condition. They did however differ in disembodiment of the own hand in the synchronous condition, patients displaying a less negative score. Furthermore, the patient group showed a larger variance in experiencing physical sensations during both conditions.

Conclusion Overall results offer modest support for differences in the subjective aspects of body ownership in patients with persistent physical symptoms. In particular, patients experienced more disembodiment of the own hand in the illusion condition and reported a wider range of physical sensations during both illusion and control conditions.

References
Botvinick, M. & Cohen, J. (1998). Rubber hands ‘feel’ touch that eyes see. Nature, 391, 756. Romano, D., Maravita, A. & Perugini, M. (2021). Psychometric properties of the embodiment scale for the rubber hand illusion and its relation with individual differences. Scientific Reports, 11: 5029.

45) Acting toward or away from the body: the role of body-centered coding in praxis difficulties in children with Autism Spectrum Disorder

L. Sebastianelli, G. De Santis, D.A. Ottone, M. Pazzaglia Introduction: The body functions as the principal spatial and sensorimotor reference frame for extracting dynamic information from movement. Action can be organized relative to the body (toward the body) or decentered from it (away from the body), requiring different demands on body schema and action planning. Praxis difficulties in autism spectrum disorder (ASD) are well documented; however, it remains unclear whether these impairments vary with the degree to which actions are anchored to the body as a reference system.

Method: Three gesture tasks were performed by children with ASD and control subjects: action comprehension, pantomime, and imitation. Each condition included items that were either away-directed (moving away from the body, such as a pencil or eraser) or body-directed (moving toward the body, such as a toothbrush or comb). Performance was evaluated based on accuracy across task type and gesture direction.

Results: Children with ASD showed a selective vulnerability in the execution and imitation of actions. Within-group analyses indicated significantly greater impairment for away-directed than for body-directed gestures. In contrast, nondirectional differences emerged in action comprehension. Thus, the differences in action representation processes for object-related actions toward and away from the body may be explained by a specific bodily role.

Discussion: This pattern suggests that action-planning difficulties in ASD may reflect reduced use or stability of body-centered spatial coding rather than impaired action knowledge. Distinguishing gesture direction relative to the body may therefore provide a sensitive marker of praxis impairment in autism, supporting embodied accounts of social-motor difficulties.

46) Listening to the Body: An Embodied Perspective on Interoception in Chronic Pain and Obesity

G. Chirchio, S. Tagini, F. Scarpina Background: Interoception is the perception, interpretation, and integration of bodily signals, including pain. Heterogeneous and unresolved evidence exists concerning its role in chronic pain (1). This study aimed to explore differences in interoceptive abilities in women with chronic pain and/or obesity, a condition frequently associated with chronic pain and interoceptive difficulties (2) and healthy women. Methods: This is a case-control cross-sectional study. Women with chronic pain and obesity (experimental group), women with obesity without chronic pain (clinical control group), and healthy and normal weight women (control group) were enrolled. The individual level of interoceptive sensibility (assessed via The Multidimensional Assessment of Interoceptive Awareness, (MAIA) and accuracy (measured with the Heartbeat Detection Task) were evaluated. Results: Participants with obesity but without chronic pain reported significantly lower scores on the MAIA components of not-distracting and not-worrying compared with the control group and the experimental group, which reported similar scores. No significant difference between groups was observed for the interoceptive accuracy.
Discussion: Obesity, rather than chronic pain, was linked to maladaptive interoceptive sensibility, especially increased worries and distraction toward bodily signals. Interoceptive accuracy was preserved, suggesting sensibility and accuracy are dissociable. Conclusions: Within an embodied pain framework (3), the evidence from this study supports the clinical relevance of assessing interoceptive dimensions in obesity, even in the absence of chronic pain. Interventions targeting interoceptive awareness may enhance body-related self-regulation and reduce pain-related distress. References: Di Lernia, D., Serino, S., & Riva, G. (2016). Pain in the body. Altered interoception in chronic pain conditions: A systematic review. Neuroscience & Biobehavioral Reviews, 71, 328-341. Narouze, S., & Souzdalnitski, D. (2015). Obesity and chronic pain: systematic review of prevalence and implications for pain practice. Regional Anesthesia & Pain Medicine, 40(2), 91-111. Tabor, A., Keogh, E., & Eccleston, C. (2017). Embodied pain—negotiating the boundaries of possible action. Pain, 158(6), 1007-1011

47) The role of functionality in embodiment: a virtual reaching study

D Cowie, J Moffatt, L Johanssen, Y Pi, S Thurlbeck, M Gillies, X Pan This work considers the role of body functionality in shaping a sense of one’s own body. We are used to a hand that lets us grasp objects with a particular force, an arm that lets us reach to a particular distance, and legs that let us move with a certain speed. What if we changed the functionality of our body? Would we be able to accept a functionally altered body as our own, or would we find that expectations of typical functionality limit our self-identification with the altered body?

In order to address these questions, we developed a Virtual Reality (VR) experience in which the user controls a virtual body with enhanced function. Specifically, the virtual body has a long arm controlled by the ‘Go-Go’ technique. This algorithm extends the virtual arm into visually far virtual space as the user stretches out their real arm, allowing interaction with visually far objects. Across two experiments we tested how users adapted to this altered body in terms of their perceptions of reaching distance, perceptions of their own body metrics, and motor control.

In a first experiment, adults, younger children (5-7 years) and older children (8-10 years) experienced a virtual arm with slightly reduced, slightly increased, or greatly increased functionality. Compared to a baseline condition where the virtual arm’s movements mapped directly onto the user’s own, only adults in the greatly increased condition felt a reduced sense of ownership over the virtual hand. All participants judged themselves able to reach further than at baseline with longer virtual arms. Movement control was more nuanced and adaptable in adults than in children, who adopted more cautious, longer decelerative phases. Overall, users of all ages adapted well to the altered-function arm. Functionality somewhat limited feelings of ownership over the arm for adults, despite their efficient motor adaptations. In contrast, altered functionality did not pose a problem for children’s ownership, although it limited their motor control.

In a second experiment, we have trained participants across three sessions with the Go-Go arm, assessing how users adapt within and between sessions, and how experience with one altered function arm may transfer and generalise to another.

48) Modulation of interoceptive accuracy by transcutaneous vagus nerve stimulation: Evidence from the heartbeat discrimination task

M. Pyasik, M. Toninelli, E. Icardi, A. Finisguerra, C. Urgesi Neural substrates of interoception – processing of the signals from within the body – include the insula, somatosensory, prefrontal and anterior cingulate cortices. However, less is known about the neurophysiological mechanisms of interoception, although it has been proposed that the vagus nerve is the key pathway between the brain and the internal organs [1]. Two recent studies provided direct [2] and indirect [3] evidence that transcutaneous electrical stimulation of the vagus nerve (tVNS) might improve interoceptive accuracy; yet, the experimental data remains scarce. The present study aimed at investigating whether tVNS improved cardiac interoceptive accuracy. 26 healthy volunteers (7 M, 19 F, mean age+/-SD = 24.6+/-4.7 years) completed two sessions of a variant of the heartbeat discrimination task. They were required to focus on their heartbeat and compare its frequency with other heartbeats presented as short audios created online based on their heart rate frequency, being parametrically slower or faster than participants’ heart rate. In each session, the task (144 trials) was first performed at baseline and then with active or sham (depending on the session) tVNS applied on the left auricular branch of the vagus nerve. Interoceptive accuracy (d’) was analyzed with a 2x2 rm-ANOVA for time (baseline, stimulation) and stimulation (active-, sham-tVNS). There was a significant interaction of time x stimulation (F = 10.87, p = .01, p.eta.sq. = .30) explained by higher d’ in the baseline of the sham condition vs the baseline of the active (p adj. = .02), and lower d’ in the sham condition vs its baseline (p adj. = .01). Baseline-standardized d’ was higher in the active vs the sham condition (t = 3.03, p = .01), indicating an increase in interoceptive accuracy after active-tVNS compared to the sham-tVNS. The results suggest that tVNS improves cardiac interoceptive accuracy, in line with the only previous study that directly investigated such effects in a similar task [2], pointing to the role of the vagus nerve in the interoceptive processing.

References 64. Critchley, H.D. and N.A. Harrison, Visceral influences on brain and behavior. Neuron, 2013. 77(4): p. 624-38. 65. Villani, V., M. Tsakiris, and R.T. Azevedo, Transcutaneous vagus nerve stimulation improves interoceptive accuracy. Neuropsychologia, 2019. 134: p. 107201. 66. Finisguerra, A., C. Crescentini, and C. Urgesi, Transcutaneous Vagus Nerve Stimulation Affects Implicit Spiritual Self-Representations. Neuroscience, 2019. 412: p. 144-159.

49) Body Image Disturbances in eating Disorders

Cera, G., Pignattai, L., Brusa, F., Boltri, M., Scarpelli, S., Gorgoni, M., Scalia, A., Manzo, F., Apicella, E., Pazzaglia, M., Lombardi, C., De Gennaro, L. & Mendolicchio, L. Theoretical background: Eating Disorders – such as Anorexia Nervosa, Bulimia Nervosa and Binge-Eating Disorder – are characterized by different degrees of Body Image Disturbances, related to dysfunctional eating habits. In our rehabilitation ward (i.e., U.O. DAN – Istituto Auxologico Italiano) ED patients follow multidisciplinary rehabilitation trajectories for almost 6 weeks, targeting even body image disturbances and improvements in BID have been observed across AN, BN and BED patients after this treatment, according to our previous studies on this theme.
Method: As part of a wider project, we are administering several measures establishing different facets of BID in ED patients, such as the Body Uneasiness Test and the Body Image Task, planning to explore their convergent validity in AN, BN and BED. Moreover, we will explore these instruments’ relationships with those assessing other clinical relevant symptoms, such as Eating Disorder Inventory, Binge Eating Scale and Yale Food Addiction Scale (i.e., severity of eating symptomatology), Beck Depression Inventory, Hospital Anxiety and Depression Scale, Social Appearance Anxiety Scale (i.e., depression and anxiety symptoms, especially across hospitalized individuals), Pittsburgh Sleep Quality Index and Morningness-Eveningness Questionnaire (i.e., sleep and circadian alterations), as well as HEXACO scale (i.e., personality traits). To achieve our aim, we hypothesize a sample of 15 patients per diagnosis, in order to gain preliminary evidence for further and wider research. The project is ongoing.

50) Tactile Localization Along the Arm: Effects of Stimulus Duration and Anatomical Landmarks

J. Khoury, S. Popescu, K. O’Regan, J. Spisak, M. Hoffmann When an itch on our skin bothers us, we can effortlessly reach to scratch it without looking. Although this seems simple, it requires multiple skills: localizing the stimulus on the skin, using knowledge of posture and body dimensions to transform that location into a target in space (1), and directing the hand accordingly. Despite decades of research, this process – referred to as tactile localization – is still poorly understood, with open questions about the roles of stimulus duration, anatomical landmarks, and individual differences. To help with this endeavor, we tested 38 participants who had to localize eight vibrotactile stimuli (200 Hz) spaced equally along the dorsal forearm and upper arm. Without vision, participants pointed to the perceived location with their right index finger, and 3D errors were recorded via motion capture. We manipulated stimulus duration – transient (100 ms) versus continuously available – to address a common limitation of prior work (2). Continuous stimulation yielded significantly better accuracy and precision than transient stimulation, supporting the view that sustained input improves localization from somatosensory signals (3). Intriguingly, longer time to reach increased error regardless of stimulus duration. Consistent with prior literature (4), localization variability was highest in the middle of each body segment, where perceptual anchoring is weakest, and reduced near anatomical landmarks (wrist, elbow, shoulder). Extending prior work beyond the forearm (5) allowed us to disentangle landmark effects from segment-boundary effects, at least with respect to response variability. We also report a systematic constant bias: errors showed a consistent shift toward the shoulder along the arm and a consistent overshoot toward the lateral side. We additionally report preliminary results on how features of motion trajectories differ across conditions and how they relate to localization performance. Crucially, we found large inter-individual differences in bias direction and magnitude – largely explained by two types of bias – consistent with the sensorimotor contingency view of tactile localization (6), which proposes that tactile perception is shaped by idiosyncratic, learned sensorimotor interactions. These findings highlight that tactile localization, far from being a simple and universal process, is shaped by stimulus properties, anatomical structure, and deeply rooted individual sensorimotor histories.

(1) Heed, T., Buchholz, V. N., Engel, A. K. & Röder, B. Tactile remapping: from coordinate transformation to integration in sensorimotor processing. Trends Cogn. Sci. 19, 251–258 (2015). (2) Macklin, A. S., Yau, J. & O’Malley, M. K. Evaluating the Effect of Stimulus Duration on Vibrotactile Cue Localizability With a Tactile Sleeve. IEEE TRANSACTIONS ON HAPTICS vol. 14 328–334 (2021) (3) Smith, P. L., & Ratcliff, R. (2004). Psychology and neurobiology of simple decisions. Trends in neurosciences, 27(3), 161-168. (4) Cholewiak, R. W. & Collins, A. Vibrotactile localization on the arm: effects of place, space, and age. Perception & Psychophysics vol. 65 1058–1077 (2003) (5) Fuchs, X., Khoury, J. A., Popescu, S. T., Heed, T., & Hoffmann, M. (2026). The Where and How of Touch: A Review of Tactile Localization Research. arXiv preprint arXiv:2601.23023. (6) O’Regan, J. K. Why Red Doesn’t Sound Like a Bell: Understanding the Feel of Consciousness. (OXFORD UNIV PR, New York, 2010)

51) RECALIBRATING BODY IMAGE IN EATING DISORDERS: A VR STUDY INTEGRATING AGENCY AND CARDIAC FEEDBACK

F. Zanetti, J.G. Herforth, K. Schönbein, J. Botev, A.P.C. Lutz Disturbances in body image are central to eating disorders and are increasingly conceptualised as reflecting alterations in interoceptive and multisensory body processing. The Virtual Reality Body Image Intervention and Assessment Suite (VRBIAS) project builds on the cardio-visual full-body illusion (CVFBI), a virtual reality paradigm that induces illusory ownership over a virtual avatar by synchronising a flashing outline surrounding the avatar’s body with the participant’s heartbeat. Temporal congruence between visual-cardiac feedback and interoceptive signals is assumed to generate the experience that the virtual body is one’s own. Such ownership illusions modulate somatosensory and interoceptive processing and are hypothesised to engage the insular cortex, a key hub for interoception and multisensory integration. Neurobiological models of anorexia nervosa implicate insular dysfunction in disturbed bodily need representation, suggesting that multisensory bodily illusions may act on mechanisms underlying eating-disorder symptomatology. VRBIAS Study 3 will extend this framework by incorporating visuo-motor congruence into the CVFBI. The design follows a 2.2 factorial structure manipulating agency (present vs. absent) and cardio-visual synchrony (synchronous vs. asynchronous). In agency-present conditions, participants’ arm and leg movements are tracked in real time and mapped onto the avatar, generating a sense of control over the virtual body. In agency-absent conditions, the avatar remains static. Synchrony is manipulated by presenting heartbeat-contingent visual feedback either temporally aligned with the participant’s ECG signal (R+200ms) or with a self-pre-recorded ECG (asynchronous condition). Visuo-motor mapping is implemented via computer vision-based skeletal tracking using a stereoscopic depth camera. Neural and physiological activity are recorded with a 64-channel mobile EEG system synchronised with an ECG device. This setup enables extraction of heartbeat-evoked potentials (HEPs) as an index of cortical interoceptive processing. The mobile configuration allows investigation under ecologically valid, embodied conditions. The primary outcome is body image improvement, operationalised as changes in questionnaire scores and reduced overestimation during body size estimation tasks. We hypothesise main effects of synchrony and agency, and a significant interaction reflecting enhanced embodiment when cardio-visual congruence and agency co-occur. At the neurophysiological level, we expect modulation of HEP amplitudes, supporting a mechanistic account of how integrating interoceptive and agentic signals may recalibrate maladaptive body representations in eating disorders.

52) Pain reshapes body representation following spinal cord injury

D.A. Ottone, L. Sebastianelli, G. De Santis, M. Pazzaglia INTRODUCTION: Body image distortion is increasingly recognized as a relevant factor in chronic pain conditions. Previous studies have documented the presence of both pain and altered body perception in individuals with spinal cord injury (SCI). However, empirical evidence supporting an association between pain and body image distortion in this population remains limited.

METHOD: We assessed 285 individuals with paraplegia or tetraplegia due to SCI using a task that provides quantitative measures of body image. All participants were in the chronic phase of injury (≥6 months post-injury) and had lesions ranging from C4 to L1. Pain localization was highly heterogeneous, ranging from chronic pain in a specific body region to widespread pain. Subjective ratings of pain “intensity” and “unpleasantness” were obtained using a numeric rating scale from 0 (no pain/not at all unpleasant) to 10 (worst pain imaginable/most unpleasant imaginable). To assess body representation, participants were presented with an anchoring stimulus on a computer screen and instructed to imagine that the displayed body part belonged to a standing mirror image of themselves. They then indicated the location on the screen, relative to the anchor, where each of several body parts would be positioned. Veridical body dimensions were derived from direct anthropometric measurements of the participants. Body image perception was compared between individuals with SCI and pain (n = 220) and those without pain (n = 65).

RESULTS: Participants with pain exhibited significantly greater body image distortions than pain-free individuals with SCI. The pain group also reported higher overall pain intensity, most frequently localized below the level of injury (45%). Correlational analyses revealed a significant positive association between body image distortion and pain intensity (r = .58), whereas no relationship emerged between specific pain location and distortion of the corresponding body part.

DISCUSSION: These findings provide strong evidence that altered body image is specifically associated with the presence and intensity of pain in SCI, rather than with pain location or chronicity, highlighting disturbances in body representation as a key feature of SCI-related pain. Considering this association in clinical practice may open new avenues for more effective interventions in individuals with SCI.

53) Investigating Flow During Social Media Scrolling: A Multimodal Approach

D. Peiti*, C. M. Malberti*, M. Sansoni, & G. Riva

• these authors contributed equally to the work Social media platforms are deeply embedded in everyday life and are specifically designed to promote sustained engagement. Their use has been associated with states of intense focus, which some authors have conceptualized as “Facebook flow,” drawing on the broader construct of flow. However, because canonical flow entails specific phenomenological and motivational components, it remains unclear whether passive social media engagement fully corresponds to flow or reflects a related form of attentional absorption. Importantly, both flow and similar immersive states involve a narrowing of attentional resources and reduced processing of peripheral information. Given that bodily self-consciousness depends on the dynamic integration of internal and external sensory signals, such attentional narrowing may transiently modulate the processing of bodily signals. Despite this theoretical relevance, flow in social media contexts has been predominantly examined through cross-sectional and correlational designs relying almost exclusively on self-report measures, which do not capture changes in sensory processing. Experimental paradigms assessing flow in real time and integrating objective behavioral indices remain indeed scarce, leaving its moment-to-moment impact on bodily awareness largely unexplored. The present study therefore investigates whether self-reported flow during Instagram use is associated with transient alterations in bodily self-consciousness. Healthy adult social media users without medical or psychiatric conditions complete an Instagram scrolling task during which randomized visual, auditory, and thermal stimuli are presented. Participants’ signal detection is assessed in real time; reduced performance during scrolling relative to baseline serves as a behavioral index of sensory attenuation. This behavioral index is examined alongside validated state measures of flow, dissociation, and cognitive absorption to distinguish flow-like engagement from detachment-related phenomena. Interoceptive accuracy is additionally measured via the Schandry heartbeat counting task to examine whether immersive scrolling is associated with altered access to internal bodily signals and whether individual differences in interoception modulate sensory attenuation effects. By moving beyond retrospective and purely correlational approaches, this study introduces an experimental, multimodal paradigm to investigate moment-to-moment fluctuations in bodily awareness during digital engagement. This methodology provides an ecologically grounded framework for examining how immersive technological environments may transiently reshape the integration of bodily signals.

54) Social Media Exposure and the Plasticity of Bodily Identity: An Experimental Study of Enfacement

C.M. Malberti*, D. Peiti*, M. Sansoni, & G. Riva

• these authors contributed equally to the work Social media platforms are increasingly shaping how individuals experience and represent their own bodies, often promoting standardized and appearance-focused content. Growing evidence suggests that prolonged exposure to such environments may influence the integration of internal and external bodily signals, potentially altering the stability of self–other boundaries. Human bodily self-consciousness relies on multisensory representations that allow individuals to distinguish their own body from others and maintain a coherent sense of identity. These representations are highly plastic and can be experimentally manipulated through body illusions such as the enfacement illusion, in which synchronous visuotactile stimulation induces identification with another face. Recent correlational findings indicate that prolonged Instagram use is associated with heightened susceptibility to face embodiment illusions, suggesting a potential digital modulation of bodily identity. However, the mechanisms underlying this association remain unclear. The present study experimentally investigates whether exposure to body-focused social media content modulates susceptibility to the enfacement illusion in virtual reality (VR). In a within-subject design, participants undergo three enfacement assessments: at baseline, following exposure to body-related (appearance-standardized) content, and following exposure to non-body-related content. Illusion strength, reflecting the degree to which participants attribute ownership, agency, and self-location to the virtual face, serves as an index of the flexibility of self–other boundaries. To further clarify the mechanisms involved, body image and body schema are assessed through self-reported questionnaires and behavioral paradigms to examine whether pre-existing characteristics of body representation influence the effects of social media exposure on embodiment susceptibility. We hypothesize that exposure to body-focused content will selectively increase susceptibility to synchronous enfacement relative to baseline and control conditions, reflecting a transient loosening of facial self-boundaries. By moving beyond correlational designs, this study provides a controlled experimental framework to examine how digital environments may dynamically reshape multisensory mechanisms underlying bodily identity.

55) Static and dynamic emotional body processing in Autism Spectrum Disorder: A Systematic Review

G. De Santis, L. Sebastianelli, D.A. Ottone, M. Pazzaglia Background. The ability to perceive and interpret emotional cues from others’ bodily movements is fundamental to adaptive social behavior and survival. Autism spectrum disorder (ASD) involves persistent difficulties in integrating perceptual and motor representations and marked impairments in social cognition, particularly for emotional cues. Yet, despite extensive research on facial and vocal emotion recognition, emotional body expressions remain relatively understudied in ASD. This systematic review synthesizes current evidence on body emotion recognition (BER) in ASD. Methods. A systematic review was conducted in PubMed, Scopus, and Web of Science, following PRISMA guidelines. Eligible studies examined recognition of basic emotions from body cues in individuals with ASD compared with typically developing (TD) controls, using behavioural and/or neuroimaging paradigms. Nineteen studies met inclusion criteria, comprising 620 individuals with ASD and 634 TD participants. Results. Individuals with ASD showed reduced accuracy in recognizing emotions conveyed by body expressions compared with TD controls. This difference emerged predominantly in studies using dynamic body expressions, whereas recognition of static body postures was largely preserved. Neuroimaging findings converge in showing atypical responses in the premotor cortex and posterior superior temporal sulcus (pSTS) to dynamic emotional body stimuli in ASD, extending to the inferior frontal gyrus (IFG), regions involved in the motor-perceptual network. Conclusions. These findings suggest that ASD preferentially encodes kinematic features of implied body movement over emotional meaning. Atypical action prediction may further disrupt processing of dynamic, but not static, emotional body cues. Together, the evidence indicates that altered processing of emotional body movement is a characteristic feature of social–motor dysfunction in ASD and highlights the need to control for implied motion in studies of emotional body expression recognition in autism.

56) The effect of multisensory training on representations of touch in 4-month-old infants

J. Leov, M. Fowles, M L. Filippetti, S. Rigato, C. de Klerk Body representations provide a foundation for key socio-cognitive abilities, including the sense of self, making it crucial to understand how they develop. Multisensory integration is thought to play a central role in shaping these representations, yet the contribution of early sensory experience remains debated. The current study investigates whether multisensory experience with a novel action - reaching with the legs - can enhance 4-month-old infants’ representation of touch on their feet across postures.

Previous research shows that 6-month-olds, but not 4-month-olds, exhibit a tactile localisation deficit when their feet are crossed (Begum Ali et al., 2015), suggesting a developmental shift from purely anatomical coding toward an attempt to integrate visual and tactile representations. This change may reflect multisensory experience gained as infants begin object-directed actions between 4 and 6 months.

The current study aims to empirically tests the causal role of multisensory experience in body representations by systematically manipulating 4-month-olds’ sensory experiences with novel leg actions. Infants are assigned to visuo-tactile, visual-only, or tactile-only training. During lab and home sessions, infants interact with a toy using their feet. The visuo-tactile group both sees their feet and receives vibrotactile feedback on contact; the visual-only group sees their feet without tactile feedback; the tactile-only group receives tactile stimulation without visual access. Effects of training are assessed using a tactile localisation paradigm with crossed and uncrossed legs, measuring behavioural responses and EEG indices of multisensory integration.

Preliminary behavioural data from the visuo-tactile group (N=11) show equivalent performance in the crossed (M = 0.62, SD = 0.17) and uncrossed (M = 0.66, SD = 0.18) leg conditions, t(10) = –0.78, p = .45, d = –0.24. Although a clear multisensory effect is not currently evident, recruitment is ongoing and expected to be complete before the conference. Findings will inform how early multisensory experience shapes body representation development and, more broadly, mechanisms underlying typical and atypical bodily self-experience.

57) Bayesian computations underlying perception of exoskeletons

F.C. van Wettum, V. Peviani, L.E. Miller We are incredibly dexterous when interacting with the world around us, not just with our own body, but also when using tools. It may appear reasonable that we should then have accurate knowledge of the whereabouts of our hands, fingers and tools. However, previous works have demonstrated that reports of perceived hand and finger locations were biased. One explanation for this perceptual bias is that the brain’s representation of the hand and finger is distorted. A recently proposed alternative explanation argues that these perceptual biases may arise from Bayesian integration, in Cartesian space, of the undistorted but noisy somatosensory signals and a latent, undistorted postural prior.
In this study, we aim to evaluate these possible explanations and investigate whether these computations extend to tools such as a finger-extending exoskeleton as well. Participants wore finger-extending exoskeletons and performed a proprioceptive matching task, matching locations on the unseen biological finger and exoskeleton finger to visual targets in virtual reality, before and after using the exoskeleton fingers to perform a series of motor tasks. By comparing the perceptual biases before and after use of the exoskeletons we examine the nature and acquisition of a possible exoskeletal postural prior as well as the robustness of the postural prior of the biological hand in the presence of a novel hand augmentation. Preliminary results suggest that localization responses to the biological hand and the finger-extending exoskeleton were spatially contiguous with various levels of perceptual biases and distortions. These findings are consistent with previous work and suggest that somatosensory priors rapidly incorporate the exoskeletal fingers. Upcoming comparisons between Bayesian models will shed light on the computations underlying proprioceptive perception of tools and our own body in the presence of tools.

58) Body Image Changes in Young Adults with Hematologic Malignancies

P. Del Sette, F. Riccardi, P. Cai, E. Sarcletti Background: Young adulthood represents a developmental stage in which body image and gendered identity play a crucial role. Cancer diagnosis and treatments during this period may affect body image through both visible and internal changes. Growing evidence suggests that immune-inflammatory processes can influence psychological experiences of the body and have been associated with body image dissatisfaction and affective symptoms. Immunotherapy may therefore contribute to changes in body image. In this pilot cross-sectional study, we investigated the relationships between immunotherapy exposure, body image changes, and psychological symptoms in young adults with hematological malignancies. Methods: Eighteen young adults with leukemia and lymphoma (8 Males; Age range = 19–37; Mean Age = 30.76 + 5.82 years) completed the Body Image Scale (BIS) and the Hospital Anxiety and Depression Scale. We calculated the proportion of participants reporting clinically relevant body image disturbance (BIS > 10). Independent-samples t-tests were conducted to examine differences in body image across immunotherapy exposure groups. Pearson correlations were performed to explore associations between body image changes and psychological symptoms. Results: Overall, 66.7% of participants reported clinically relevant body image disturbance. Patients receiving, in addition to chemotherapy, immunotherapy reported significantly greater body image changes, Mean = 19.60 + 6.74, compared to those not receiving immunotherapy, Mean = 7.75 + 8.52, t(16) = .3.30, p = .005. Body image changes were positively associated with depressive symptoms, r = .493, p = .038, but not with anxiety symptoms, r = .213, p = .395. Conclusions: In young adults with hematologic malignancies, immune-related treatments may be associated with increased body image changes, which in turn are linked to depressive symptoms. The present results suggest that immune-related bodily processes may influence patients’ subjective experience of their bodies and highlight the importance of addressing body image in psychosocial care for young hematological patients. These findings highlight the importance of addressing body image within psychosocial care for young adults with hematological malignancies and point to the potential relevance of integrating body-focused approaches in supportive interventions.

59) Altered Body Representations in idiopathic Cervical Dystonia and their modulation following Botulinum Neurotoxin treatment

I. Martinelli, L. De Iaco, M. Ramella, S. Konik, G. Bottini, G. Giannini, A. Castagna*, M. Bassolino* Idiopathic cervical dystonia (iCD) is the most common adult onset focal dystonia. It is characterized by involuntary contractions of cervical muscles that induce abnormal postures and movements, often tremulous or jerky, along with sensory tricks, and is associated with dysfunctions of the basal ganglia, sensorimotor cortices, and cerebellar networks. Beyond motor symptoms, iCD patients present pain, sensory alterations and disrupted multisensory integration, potentially affecting their body representations (BRs).
The present study aims to assess and characterize the phenomenology of BRs alterations in iCD patients, and to quantify their modulation following botulinum neurotoxin treatment, which is the gold standard treatment. A multicenter study was conducted. Twenty-three patients were enrolled and assessed before treatment, of whom 20 completed the post-treatment evaluation 4 weeks after injection, when the maximal clinical efficacy is recorded. Patients were evaluated for: iCD severity, pain and disability (Toronto Western Spasmodic Torticollis Rating scale, TWSTRS), subjective body perception (adapted Affected Limb Perception Questionnaire ALPQ for the cervical region), proprioceptive body midline (straight-ahead task implying active motor pointing) and visuo-proprioceptive midline (bucket test assessing subjective visual vertical). Before treatment, a relevant percentage of patients exhibited a wide range of altered body perception of the cervical segment, including disownership (17%), perceived changes in physical characteristic (weight=39%; position=39%; size=26%; temperature=13%), involuntary (83%) and illusory movements (35%), emotional impact of motor difficulties (77%) and negative attitude toward the affected region (39%). ALPQ scores correlated with TWSTRS-total score (rho=0.46, p=0.0026) and especially with the pain subscale (rho=0.50, p=0.016). After treatment, TWSTRS (p<.001) and ALPQ total scores (p=0.004) significantly decreased, with improvements also in visuo-proprioceptive (p=0.033) but not motor-mediated body midline (p=0.268). Overall, these findings indicate that persons with iCD present alterations in BRs and that botulinum neurotoxin treatment produces changes and potential beneficial effects on both clinical status and BRs disturbances.

60) Perceived Gender Shapes Bias in Weight Categorisation

K.J. McKenzie & K. Irvine Perceptions of body weight are systematically biased: individuals tend to overestimate lighter bodies and underestimate heavier ones, creating a “pull” toward the average body size. This phenomenon, known as contraction bias, is observed across both self-perception and judgments of others and has been shown to be particularly pronounced in women judging other women. Moreover, weight categorisation is influenced by stimulus gender, with men’s bodies more likely to be assigned a lower weight category than is objectively accurate, and women’s bodies more likely to be assigned a higher one. The current research sought to examine how perceived gender and internalised gender norms shape contraction bias in weight categorisation. In study 1, participants of all genders categorised the weight status of 3D body stimuli varying in perceived gender (female, gender-neutral, and male) and BMI. Contraction bias was observed across all stimuli, but female bodies were consistently perceived as heavier than gender-neutral and male bodies at the same BMI, across all BMI categories and regardless of participant gender.
Study 2 examined whether this bias was driven by the visual characteristics associated with gender or by internalised reference means associated with gender. Participants categorised the weight status of identical gender-neutral 3D body stimuli that had been labelled as either “Female” or “Male.” Here, we found that at the same BMI, when gender-neutral stimuli were labelled as female they were consistently perceived as heavier than when labelled as male. This suggests that gender-based expectations and internalised social norms, rather than purely visual bodily features, systematically influence weight perception.
These findings highlight that weight perception is not purely objective but shaped by gendered expectations. These results may also help to explain the higher rates of body dissatisfaction, body image concerns, and eating disorder risk among trans and gender-expansive individuals.

61) A Probabilistic Kinematic Account of Tactile Spatial Localization

Huseyin O. Elmas, W. Pieter Medendorp, Luke E. Miller Spatial tactile localization requires transforming the tactile stimulus location from skin-surface into an external reference frame, a process that depends on the representation of limb configuration. Because both tactile and proprioceptive inputs are noisy, this transformation must operate under uncertainty. One principled way to handle such uncertainty is to employ Bayesian inference, though the exact nature of its application to tactile remapping is unclear. To fill this gap, we investigated how Bayesian computations integrate tactile inputs with proprioceptive body representation. We developed probabilistic kinematic models in which tactile localization emerges from Bayesian inference over uncertain body configurations and sensory inputs. The brain is assumed to combine a noisy tactile signal encoding stimulus location on the skin with a noisy proprioceptive estimate of arm configuration and the body’s geometry to compute a posterior estimate of touch location in space. We consider models that differ in the representational space in which prior beliefs about body configuration are defined. Together, these models predict posture-dependent patterns of localization bias and variability that reflect the structure of sensory uncertainty, body geometry and prior beliefs. We tested these predictions in VR using a task where participants adopted several arm configurations, spanning a range of shoulder and elbow angles, with the arm occluded from view. On each trial, a mechanical stimulus was delivered to one of six locations distributed along the forearm while participants indicated the perceived touch location using a VR-tracked mouse. Arm posture was held constant within each block of trials and varied across blocks. Each block also included landmark trials in which participants localized their elbow and wrist. Preliminary analyses have uncovered coherent alignment between proprioceptive and tactile representations, with both spaces exhibiting errors that systematically vary across arm postures. Furthermore, the error magnitude and direction increases concurrently with distance from the elbow and arm angle, consistent with the geometric predictions of our kinematic models. Ongoing model fitting aims to characterize whether these biases reflect a prior over body configuration, and which representational space best captures how the brain uses internal body models to guide tactile perception in external space.

62) Peripersonal Space and Body Schema in Three Dimensions

D. Fray, P. Caggiano Successful interaction with the environment requires representations of both the body and the surrounding space. The sensorimotor representation of the body is described by the body schema; while the peripersonal space refers to the spatial representation about the individual, particularly relevant for interactions with objects through multisensory integration. Although both representations show similar plastic adaption effects following tool use, the interrelated nature of the two systems remains unclear. Therefore, two experiments were planned to assess this relationship by comparing perceived reachability and peripersonal space boundaries within the same environment.

Both studies utilise a virtual-reality methodology in which participants sat in the centre of a radiating hemisphere of targets, which moved radially towards or away from them. Experimental conditions manipulated visual and proprioceptive information to examine their contribution to the two representations. In the first experiment, participants moved targets to their perceived maximum reaching distance. Results revealed a significant overestimation or reach particularly for lower targets. However, when proprioceptive information was available, the overestimation reduced . In the second experiment, peripersonal space boundaries are assessed using a visual-tactile detection task. The findings of the two studies will be compared to determine the extent to which emerging patterns would suggest a shared mechanism or dissociation between perceived reachability and peripersonal space representation.

63) Body Representation and Body Size Estimation in Eating Disorders and Obesity

N. Borella, A. De Chino, P. Zuglian, G. Mattavelli A distorted perception of one’s own body represents a core feature in the psychopathology of eating disorders (EDs). These alterations often persist despite years of treatment. Within the broader framework of body image, body representation reflects the individual’s subjective expectancy of their body image. It also encompasses stored information about how the body is perceived (Engel & Keizer, 2017; Yamamotova et al., 2017).

According to the theoretical framework proposed by Longo (2015), body representation can be conceptualized along two primary dimensions: perceptual versus conceptual, and implicit versus explicit (Provenzano et al., 2024). These dimensions can be captured by body size estimation (BSE) tasks. BSE tasks assess how individuals judge the size and shape of their bodies using both metric and depictive techniques (Peel et al., 2026). Despite increasing research literature on body image, the theoretical framework remains quite heterogeneous. This is reflected in the variability of experimental applications of BSE tasks.

The present meta-analytic study aims to update the evidence regarding studies investigating the distortion of BSE in patients with anorexia nervosa (AN) and bulimia nervosa (BN) compared to healthy controls. Considering recent technology-based approaches, we seek to further explore distinctions and relationships among BSE tasks, including the use of avatars representing individuals’ bodies. We also aim to better understand their use in clinical applications and to examine body representation alterations across different types of EDs and in individuals with obesity.

Our findings highlight differences in how the body is experienced by individuals with eating disorders compared to controls, partially confirming results from the previous meta-analysis. Additionally, they provide new evidence regarding the use of BSE tasks to examine body representation. Overall, the results offer further insight into body representation and its assessment across clinical populations to improve our knowledge related to body representation and its alteration.

64) PeriPersonal Space-Time: behavioral investigation of the temporal sensitivity of space dependent visuo-tactile integration

I. Chauhan, A. Custo, M. Akselrod, T. Bertoni, A. Serino PeriPersonal Space (PPS) refers to the representation of the space surrounding the body, allowing physical interactions between the individual and the environment. PPS has often been described as an enhanced integration of tactile information with exteroceptive information in a space-dependent manner. This multisensory integration allows contact prediction, for which temporal dynamics are also of prime importance. However, knowledge on how temporal features of bodily and external stimuli modulates the space-dependent integration is lacking. In the present study, healthy participants underwent a classical PPS paradigm during which they had to press a button as fast as possible when they felt a tactile stimulus on their hand, while a visual stimulus was presented at different distances from the body. Crucially, various delays were applied between the tactile and visual stimuli, allowing to orthogonally manipulate contingencies between bodily and external stimuli both in time and space. For the different delay and distance combinations, PPS activation was indexed as the reaction time facilitation induced in visuo-tactile condition as compared to unimodal tactile responses. Results show a classic space-dependent PPS effect (i.e., stronger integration for close stimuli), a temporal binding effect (i.e., stronger integration for short delays), and importantly an interaction between spatial and temporal features of visuo-tactile stimulation, according to natural spatiotemporal regularities. That is, the PPS system is activated as a function of the coherence of stimuli in space and time. Such findings indicate that PPS captures interaction potentials between the body and external stimuli across both the spatial and the temporal dimensions, thus suggesting a theoretical reframing as PeriPersonal Space-Time (PPST).

65) Increased cortical sensitivity in patients with chronic hand pain

Shasha Wei, Alex R. Wade, Daniel H. Baker, Catherine E.J. Preston Background: Chronic hand pain is frequently accompanied by diminished tactile acuity and modified somatosensory processing. However, it remains unclear whether chronic hand pain affects tactile processing. This study aims to investigate whether vibrotactile signal processing is disrupted in chronic hand pain by assessing vibration thresholds and corresponding brain responses.
Methods: Twenty-five individuals with chronic hand pain and 25 age-matched controls participated. In Experiment 1, psychophysical thresholds were measured using a two-interval forced-choice (2IFC) task under two vibration conditions: “Full-26 Hz”, in which all ten fingers were stimulated simultaneously, and “Interleaved-26 Hz”, in which five alternating fingers were stimulated. In Experiment 2, steady-state somatosensory evoked potentials (SSSEPs) were recorded during three conditions: “Alternating-26 Hz” (five alternating fingers), “Full-26 Hz” (all ten fingers), and “Interleaved-26/23 Hz”, where five fingers received 26 Hz vibration and the remaining five received a 23 Hz mask. Results: Psychophysical experiment revealed that patients exhibited significantly reduced detection and discrimination thresholds compared with controls (p = 0.05), indicating hypersensitivity to mechanical stimuli consistent with central sensitisation, characterised by increased central responsiveness to sensory stimuli. Notably, a significant summation effect (p < 0.001) was observed at detection threshold in the chronic hand pain group but not in controls. SSSEPs were consistently larger (p < 0.001) in the pain group across three stimulation conditions. Computational modelling results demonstrated reduced semi-saturation constants (C..) in the chronic hand pain group, indicating increased cortical sensitivity. Conclusions: These findings support central sensitisation and enhanced cortical sensitivity in chronic hand pain.

66) Positive Virtual Enfacement Illusion induces positive body image and pain relief in female with chronic migraine

Marta Matamala-Gomez, Marta Allena, Elena Guaschino, Natascia Ghiotto, Roberto De Icco, Grazia Sances, Cristina Tassorelli, Sara Bottiroli Chronic migraine (CM) is a highly disabling neurological disorder characterized by frequent headache episodes and substantial psychosocial burden. Current pharmacological treatments show limited efficacy and tolerability, highlighting the need for innovative non-pharmacological approaches. Virtual reality (VR) has emerged as a promising tool for pain modulation, not only through attentional distraction but also via manipulation of body representation. In particular, the enfacement illusion—a form of virtual body ownership induced through synchronous visuo-tactile stimulation—offers a novel avenue to influence affective and perceptual components of pain. This study investigates the efficacy of a VR-based enfacement illusion intervention in reducing pain perception and improving body image and emotional regulation in patients with CM. Fifty female participants diagnosed with CM were enrolled in a double-blind randomized controlled trial and assigned to either an experimental group (virtual enfacement illusion, VEI) or a control group (pleasant immersive VR environment, VE). Participants underwent three VR sessions over one week, with assessments of pain (VAS), affect (PANAS), and body image (BIQ) conducted before and after each session, alongside psychological questionnaires administered at baseline and post-intervention. Results revealed a significant group-by-time interaction, with the VEI group showing greater reductions in pain intensity compared to the control group, particularly at the final session. Both groups exhibited improvements in negative affect; however, only the VEI group demonstrated significant enhancements in body image perception. Furthermore, correlational analyses indicated that improvements in body image and positive affect were associated with greater pain reduction in the VEI group. Measures of embodiment confirmed successful induction of the enfacement illusion, suggesting that multisensory integration and altered self-representation contributed to the observed effects. These findings support the therapeutic potential of VR-based embodiment techniques in CM. Specifically, inducing the virtual enfacement illusion may modulate pain by targeting both sensory and affective dimensions through changes in body representation and emotional processing. This approach represents a promising, non-invasive adjunct to existing treatments and underscores the importance of personalized, cognition-based interventions in chronic pain management.

67) Two Patients with Stroke Treated with Psilocybin

G. Hasler This report describes two cases of ischemic stroke patients treated with psilocybin-assisted therapy during inpatient neurorehabilitation at Cereneo in Switzerland. Psilocybin was administered under medical supervision with psychological support before, during, and after treatment. A 72-year-old woman with right hemispheric stroke and recurrent depression received five psilocybin sessions (15–20 mg), which were well tolerated and associated with transient improvements in mood, motivation, engagement in rehabilitation, and unexpectedly accelerated motor recovery after the third session. A 44-year-old man with post-stroke aphasia underwent two psilocybin sessions (15 mg and 25 mg), showing gradual improvements in reading speed, object naming, expressive language, and depressive symptoms, with only mild and transient side effects. These preliminary observations suggest that psilocybin may be safely administered in selected stroke patients and could support neurorehabilitation through antidepressant and neuroplasticity-enhancing effects. Controlled clinical trials are needed to further evaluate safety, efficacy, and optimal treatment protocols in stroke rehabilitation.