Neurocognitive mechanisms of social inferences in typical and autistic adolescents

Many of our efforts in social interactions are dedicated to learning about others. Adolescents with autism have core deficits in social learning, but a mechanistic understanding of these deficits and how they relate to neural development is lacking. The current study aimed to specify how adolescents with and with autism represent and acquire social knowledge and how these processes are implemented in neural activity. Typically developing (TD) adolescents (N=26) and adolescents with autism (N=20) rated in the MR scanner how much three peers liked a variety of items and received trial-by-trial feedback about the peer9s actual preference ratings. In a separate study, we established the preferences of a new sample of adolescents (N=99), used to examine population preference structures. Using computational models, we tested whether participants in the MR study relied on preference structures during learning and how model predictions were implemented in brain activity. TD adolescents relied on average population preferences and prediction error (PE) updating. Importantly, PE updating was scaled by the similarity between items. In contrast, preferences of adolescents with autism were best described by a No-learning model that relied only on participants own preferences for each item. Model predictions were encoded in neural activity. TD adolescents encoded PEs in the putamen and adolescents with autism showed greater encoding of own preferences in the angular gyrus. We specified how adolescents represent and update social knowledge during learning. Our findings indicate that adolescents with ASD rely only on their own preferences when making social inferences.