Developmental changes in emotion recognition from human biological motion in children with intellectual developmental disorders and typically developing peers.

Individuals with intellectual developmental disorders (IDD) often experience difficulties in emotion recognition. Previous research has primarily investigated these difficulties through tasks involving emotional facial expressions. However, no study has yet explored emotion recognition through other modalities, such as dynamic bodily expressions. The current study aimed to investigate developmental changes in emotion recognition through human biological motion presented in point-light displays (HBM-PLD) in children with IDD. Forty-two children with IDD and 157 typically developing (TD) children aged between 4 and 18 years participated in tasks requiring the recognition of emotional HBM-PLD (joy, anger, fear, sadness, and neutral) presented on a screen. We relied on a matched-pair design with two comparison groups: 31 pairs of participants were matched by chronological age (CA-matching) and 36 pairs were matched by fluid intelligence score assessed with Raven's 2 Progressive Matrices (CE-matching). Results showed that children with IDD performed significantly worse than their TD peers when matched by chronological age. However, when matching was based on cognitive efficiency, these differences were greatly reduced, bringing the performances of children with IDD closer to those of younger TD children with similar cognitive efficiency. Generalized additive modeling (GAM) demonstrated that these differences could be explained by chronological age (reflecting experience related to development) and fluid intelligence (reflecting reasoning abilities). These results, obtained for the first time using HBM-PLD, provide empirical support for the hypothesis that emotion recognition abilities in children with IDD may reflect a developmental delay. The discussion highlights important considerations for developing targeted interventions tailored to individuals with IDD.