Disrupted brain communication in autism spectrum disorder (ASD) is supported by an extensive literature of neuroimaging findings, as reflected in disrupted white matter microstructure and functional connectivity analyses (synchronization of activation across brain regions) of functional magnetic resonance imaging (fMRI) data, and has great potential to lead to a biomarker for the disorder. Unfortunately, very few fMRI studies include young children with ASD, because of challenges with remaining still and tolerating the scanner environment. Therefore, a gap exists in our understanding of brain synchronization development throughout childhood in individuals with ASD, a period during which individuals are most sensitive to treatment. Recently, techniques have been developed to analyze “neural synchrony” in electroencephalography (EEG) data, and have been proposed to shed light on connectivity in autism. Because EEG is well tolerated in young and low-functioning children, such measures would be able to illuminate brain connectivity in ASD throughout development. Therefore, this project will implement neural synchrony analyses of EEG data to examine brain synchronization in children with ASD. Based on previous findings of reduced adaptation in brain connectivity in ASD, this study will also explore the plasticity of EEG responses and synchrony in children with ASD in the context of a learning paradigm. Understanding the plasticity of these neural measures in children with ASD and neurotypical children will inform us of their utility as outcome measures in future intervention studies. These measures of neural plasticity and synchrony also will be examined with clinical measures of ASD symptoms to determine the degree to which neural disruptions affect behavior, potentially informing future targets for treatment. This project will improve the field’s understanding of brain connectivity and plasticity in ASD throughout development and their potential as outcome measures of future interventions.