Action execution and observation in autistic adults: A systematic review of fMRI studies.

This research looked at brain scans of autistic adults while they performed actions or watched others perform actions. The study found that autistic adults use the same brain areas as non-autistic adults, but these areas work differently - sometimes more active, sometimes less active. These differences in brain activity may help explain why some autistic people have motor difficulties and challenges understanding what others are doing or intending to do.

This systematic review examined fMRI brain imaging studies of action execution and observation in autistic adults. The review found that autistic adults use similar brain regions as neurotypical adults when performing or watching actions, but with different patterns of activation intensity. During action execution, differences were observed in motor-related areas including precentral cortex, parietal cortex, inferior frontal gyrus, middle temporal gyrus, occipital cortex, and cerebellum. During action observation, differences primarily involved the inferior frontal gyrus, precentral gyrus, and middle temporal gyrus.

The findings suggest atypical functioning in brain networks responsible for motor planning and predictive control, which may contribute to difficulties understanding others' actions and intentions in autism.

Findings suggest motor difficulties in autism may stem from atypical brain activation patterns rather than damaged neural networks. Understanding these differences could inform targeted interventions for motor skills and social understanding difficulties in autistic individuals.

Sample size not reported for the systematic review. The abstract does not specify the number of included studies, participant characteristics, or methodological quality assessment of reviewed studies, limiting evaluation of the evidence strength.

Motor impairments are common in individuals with autism spectrum disorder (ASD) although less is known about the neural mechanisms related to such difficulties. This review provides an outline of functional magnetic resonance imaging (fMRI) findings associated with execution and observation of naturalistic actions in autistic adults. Summarized outcomes revealed that adults with ASD recruit similar brain regions as neurotypical adults during action execution and during action observation, although with a difference in direction and/or magnitude. For action execution, this included higher and lower activity bilaterally in the precentral cortex, the parietal cortex, the inferior frontal gyrus (IFG), the middle temporal gyrus (MTG), the occipital cortex, and the cerebellum.

For action observation, differences mainly concerned both higher and lower activity in bilateral IFG and right precentral gyrus, and lower activity in MTG. Activity overlaps between action execution and observation highlight atypical recruitment of IFG, MTG, precentral, and parieto-occipital regions in ASD. The results show atypical recruitment of brain regions subserving motor planning and/or predictive control in ASD. Atypical brain activations during action observation, and the pattern of activity overlaps, indicate an association with difficulties in understanding others' actions and intentions.