Autistic adults exhibit typical sensitivity to changes in interpersonal distance

The visual processing differences seen in autism often impede individuals’ visual perception of the social world. In particular, many autistic people exhibit poor face recognition. Here, we sought to determine whether autistic adults also show impaired perception of dyadic social interactions – a class of stimulus thought to engage face-like visual processing. Our focus was the perception of interpersonal distance. Participants completed distance change detection tasks in which they had to make perceptual decisions about the distance between two actors. On half of the trials, participants judged whether the actors moved closer together; on the other half, whether they moved further apart. In a non-social control task, participants made similar judgements about two grandfather clocks. We also assessed participants’ face recognition ability using standardized measures. The autistic and non- autistic observers showed similar levels of perceptual sensitivity to changes in interpersonal distance when viewing social interactions. As expected, however, the autistic observers showed clear signs of impaired face recognition. Despite putative similarities between the visual processing of faces and dyadic social interactions, our results suggest that these two facets of social vision may dissociate.