Regional EEG alpha power, coherence, and behavioral symptomatology in autism spectrum disorder

OBJECTIVE: Although distinct patterns of resting brain electrical activity (EEG) and functional connectivity are believed to distinguish individuals with autism spectrum disorders (ASD) from their unimpaired peers, researchers have only recently begun to link patterns of brain activity and connectivity to behavior in ASD. METHOD: We examined regional eyes-closed and eyes-open EEG alpha power and coherence at rest in relation to self-reported perceptual and social behavior in 15 adults diagnosed with ASD and a matched comparison group of 16 unimpaired adults. RESULTS: The groups did not differ on eyes-closed EEG alpha power or coherence, but adults with ASD showed less alpha suppression for the eyes-open condition than did controls. In the ASD group, preferential attention to detail (perceptual domain) was associated with lower levels of alpha activity and reduced coherence in posterior regions. No relations between social interaction difficulties (social domain) and alpha measures were found for either group alone. CONCLUSIONS: These relations suggest that the processing of perceptual details may be carried out by relatively less synchronized neuronal units in adults with ASD, and may be relatively automatic. SIGNIFICANCE: Findings are discussed in relation to recent models of narrow minicolumnar brain structure and reduced functional neural connectivity in ASD.