Execution, imitation and observation of naturalistic actions in autistic children and adolescents: a systematic review of fMRI studies

Introduction: Motor difficulties are frequent in autistic children and associated with diverse social behavior, possibly due to atypical neural processing subserving internal action models. This systematic review synthesizes results from current functional magnetic resonance imaging (fMRI) research of brain activation during execution, imitation and observation of naturalistic actions in autistic children and adolescents (<18 years). Methods: = 3). Results: Between-group differences included reduced cerebellar activations for execution in autistic children; higher activity in left-lateralized motor processing regions for imitation; and lower activity in temporoparietal, posterior cingulate and anterior prefrontal cortex for observation. Discussion: Findings suggest that atypical brain activation during action execution, observation and imitation in autistic youth is frequent and largely support the notion of aberrant formation and use of motor representations in autism development. Although, due to the limited number of studies, small samples, variability in fMRI pipelines, and task specific nature of the results, interpretations require caution and further investigations are warranted.