Inferring power and dominance from dyadic nonverbal interactions in autism spectrum disorder

Research studies to date have revealed conflicting results with respect to the processing of nonverbal cues from social interactions in autism spectrum disorder (ASD). Therefore, the aim of the present study was to investigate the contribution of two important factors for the perception of dyadic social interactions, namely (a) the movement contingency and (b) the spatial context. To this end, 26 adult participants with ASD and 26 age-, sex-, and IQ-matched typically developed control participants observed animations presenting nonverbal interactions between two human virtual characters enacting power relationships. We manipulated (a) movement contingency by exchanging one of the two original agents with an agent from another dyad and (b) spatial context by changing agents' spatial orientation to a back-to-back position. Participants were asked to rate dominance and submissiveness of these agents. Results showed that the movement contingency manipulation affected accuracy and consistency of power perception and that the spatial context manipulation slowed down reaction times comparably in both groups. With regard to group differences, individuals with ASD were found to judge power relationships slower compared to control participants, potentially suggesting a more explicit processing style in ASD. Furthermore, the spatial context manipulation slowed down the reaction times more in the contingent compared to the non-contingent conditions only in the ASD group. These findings contribute to the ongoing debate whether individuals with ASD have difficulties in understanding nonverbal cues in a dyadic context by suggesting that they do so in more subtle ways than previously investigated. Autism Research 2019.