A new behavioral and neural marker of social vision

Abstract

Research on face perception has revealed highly specialized visual mechanisms such as configural processing, and provided markers of interindividual differences -including disease risks and alterations- in visuoperceptual abilities that traffic in social cognition. Is face perception unique in degree or kind of mechanisms, and in its relevance for social cognition? Combining fMRI and behavioral methods, we address the processing of an uncharted class of socially relevant stimuli: minimal social scenes involving configurations of two bodies spatially close and face-to-face. We report category-specific activity for facing (vs. non-facing) two-body configurations in visual cortex. That activity shows face-like signatures of configural processing -i.e., stronger response and greater susceptibility to stimulus inversion for facing (vs. non-facing) dyads-, and is predicted by performance-based measures of body-dyad perception. Moreover, individual performance in body-dyad perception is reliable, stable-over-time and correlated with the individual social sensitivity, coarsely captured by the Autism-Spectrum Quotient. Further analyses clarify the relationship between single-body and body-dyad perception. We propose that facing dyads are processed with the same high specialization of the most biologically/socially relevant stimuli: faces. Like face perception, facing-dyad perception can provide a measure of basic (visual) processes that lay the foundations for understanding others, their relationships and interactions.

The role of motion in the neural representation of social interactions in the posterior temporal cortex

“…Similarly, our results in EBA are in line with some previous reports that EBA is sensitive to dynamic interactive information – at least when stimuli depict human bodies (Abassi & Papeo, 2020; Bellot et al, 2021; Walbrin & Koldewyn, 2019; though see Walbrin et al, 2020). In contrast to previous work (Abassi & Papeo, 2020, 2021), however, in our results EBA did not exhibit preferential activation for social interactions versus non-interaction when scenes were static. Crucially, the stimuli used in the current work were naturalistic, every-day social scenes that included a variety of interactive cues.…”

“…Second, and in contrast to SI-pSTS, we hypothesised that EBA would show a main effect of motion (see Downing et al, 2001), but only weak sensitivity to interactive information. We did not expect EBA to be particularly sensitive to interactive information in dynamic scenes, but instead expected that EBA might be more responsive to interactive cues conveyed through static body cues, in line with prior work (Abassi & Papeo, 2020, 2021).…”

“…However, the SI-pSTS is not the only posterior region implicated in visual interaction perception. Recent studies using static images of dyads who are either facing each other, or not, has suggested that extrastriate body area (EBA), rather than the pSTS, is more uniquely engaged by facing human dyads (Abassi & Papeo, 2020, 2021). In addition, two studies using dynamic dyads that gesture and/or move towards vs. away from each other find that the EBA, as well as pSTS, plays a role in processing social interactions (Bellot et al, 2021; Walbrin & Koldewyn, 2019).…”

“…Indeed, recent work suggests that observed interactions are perceived and processed in a way that extends beyond the sum of perceiving multiple individuals (Abassi & Papeo, 2020, 2021; Bellot et al, 2021; Isik et al, 2017; Masson & Isik, 2021; Walbrin et al, 2018; Walbrin & Koldewyn, 2019). Studies focused on dynamic interactions (Isik et al, 2017; Masson & Isik, 2021; Walbrin et al, 2018) have highlighted a region of the posterior superior temporal sulcus (pSTS) as being selectively involved in the perception of observed social interactions.…”

Isolating Action Prediction from Action Integration in the Perception of Social Interactions

“…Therefore, it could be that individuals with HFA differently integrate the information from individual actors in a simultaneous interaction. In support of this alternative interpretation, a recent study shows that individuals with higher autistic traits show a lower tendency to process images of two bodies in a social configuration as unitary percept [19]. These observations further motivate using an experimental approach that can disambiguate between predictive and integrative mechanisms.…”