Perception of biological motion and actions in Autism: A systematic review

Detecting and recognising the Biological Motion (BM) of other people provides essential information to understand others' actions and intentions, thus facilitating social interactions. Difficulties with social interaction are a hallmark of autism and may stem from altered perceptual recognition or interpretation of others' actions. This systematic review investigates whether BM perception in autistic individuals is influenced by the different categories of BM processing and the methodological differences between different BM paradigms. It also explores potential overlap between performance in non-biological motion tasks and BM perception. A total of 51 empirical studies compared BM task performance between 1066 autistic individuals and 1086 non-autistic individuals. Autistic individuals demonstrated poorer performance in BM discrimination tasks that involved greater social cognition. There were no consistent patterns regarding methodological differences across the tasks, such as stimulus types, motion varieties, or level of instructions. When investigated, poorer performance in BM tasks was often mirrored in non-biological motion tasks, suggesting potential overlap in underlying processing mechanisms. Future research should explore a broader range of ages, directly compare performances across tasks, and level of instructions to advance understanding of perceptual processing in autism.