Abstract: Perceiving and interpreting others’ emotional states from social signals plays a critical role in social interaction and human survival. Facial expressions present the most common social signals conveying emotional clues. Beyond facial expressions, biological motion (BM) provides another effective source of emotional information and possesses unique advantages in emotion perception. Here, we reviewed recent advances in the field of BM emotional processing, focusing on underlying mechanisms, individual differences, and clinical abnormalities. Existing evidence suggests that emotional processing of BM relies on the integration of global configuration and local motion cues, and shows certain processing advantages for specific emotions. At the neural level, this process is primarily supported by the social brain network centered on the posterior superior temporal sulcus (pSTS). Moreover, despite substantial differences in low-level visual features, BM and facial expressions partially overlap in behavioral performance and neural mechanisms and may share a common social perceptual processing system. In addition, the processing of emotional information from biological motion is modulated by factors such as gender, age, and individual traits (e.g., autistic traits and trait anxiety), and shows varying degrees of abnormalities in clinical populations including autism, schizophrenia, and individuals with emotional and cognitive disorders. Overall, this review integrates research on emotional processing of biological across mechanistic, individual-difference, and clinical-abnormality dimensions. This not only broadens our understanding of a general social emotion perception system, but also provides potential directions for the assessment and intervention of related psychiatric and neurological disorders.

Key words: biological motion, emotion perception, facial expressions, autism spectrum disorder, schizophrenia