Silvia Angelica Puertas Cespedes

• Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by differences in social communication and interaction, as well as restricted and repetitive behaviors, interests, or activities. ASD is frequently associated with abnormalities in language production and comprehension. Consequently, research aimed at identifying the neural mechanisms underlying ASD has often focused on the language system. Given that language processing is typically characterized by leftward hemispheric specialization, it has been proposed that ASD may be associated with atypical patterns of hemispheric asymmetry. Despite extensive research investigating functional hemispheric lateralization for language in ASD, no quantitative synthesis has comprehensively examined this phenomenon across neuroimaging, electrophysiological, and behavioral evidence in ASD.Consequently, the extent to which hemispheric specialization differs from that of neurotypical (NT) individuals remains unclear. A systematic review and meta-analysis of 32 studies, including 35 independent cohorts with 629 individuals with ASD and 673 NT controls, integrating findings from multiple modalities (i.e., hemodynamic imaging, electrophysiology, and behavioral methods) can help address these inconsistencies and clarify whether atypical brain lateralization for language is a consistent feature of ASD or varies according to measurement technique, cognitive domain, or participant characteristics. The meta-analysis revealed a significant reduction in hemispheric lateralization in individuals with ASD compared to NT controls. Overall, these findings suggest that altered hemispheric specialization may represent an important neurobiological characteristic of ASD and highlight the relevance of considering language lateralization in future research on autism and communication functioning.