Brain activity during facial processing in autism spectrum disorder: an activation likelihood estimation (ALE) meta-analysis of neuroimaging studies

Abstract

BackgroundThough aberrant face processing is a hallmark of autistic spectrum disorder (ASD), findings on accompanying brain activity are divergent. Therefore, we conducted an activation likelihood estimation (ALE) meta-analysis of studies examining brain activity during face processing. MethodsWe searched PubMed and PsycINFO using combinations of terms as fMRI, Autism Spectrum Disorder, Face Perception. Eligible studies reported on DSM-diagnosed ASD patients, compared to controls (HC), using face stimuli presented in fMRI and reporting whole-brain analysis coordinates. We compared two approaches: "convergence of differences" (primary analysis) using study-level coordinates from ASD vs. HC contrasts, and "differences in convergence" (secondary) pooling coordinates within each group separately, and contrasting the resultant ALE-maps. ResultsThirty-five studies (655 ASD and 668 HC) were included. Primary analysis identified a cluster in amygdala/parahippocampus where HC showed greater convergence of activation. Secondary analysis yielded no significant results. ConclusionsResults suggest that ASD dysfunction in face processing relies on structures involved in emotional processing rather than perception. We also demonstrate that the two ALE methodologies lead to divergent results.