Archival ReportAutism, Attention, and Alpha Oscillations: An Electrophysiological Study of Attentional Capture

BackgroundAutism spectrum disorder (ASD) is associated with deficits in adaptively orienting attention to behaviorally relevant information. Neural oscillatory activity plays a key role in brain function and provides a high-resolution temporal marker of attention dynamics. Alpha-band (8-12 Hz) activity is associated with both selecting task-relevant stimuli and filtering task-irrelevant information.MethodsThe present study used electroencephalography to examine alpha-band oscillatory activity associated with attentional capture in 19 children with ASD and 21 age- and IQ-matched typically developing children. Participants completed a rapid serial visual presentation paradigm designed to investigate responses to behaviorally relevant targets and contingent attention capture by task-irrelevant distractors, which either did or did not share a behaviorally relevant feature. Participants also completed 6 minutes of eyes-open resting electroencephalography.ResultsIn contrast to their typically developing peers, children with ASD did not evidence posterior alpha desynchronization to behaviorally relevant targets. Additionally, reduced target-related desynchronization and poorer target detection were associated with increased ASD symptomatology. Typically developing children also showed behavioral and electrophysiological evidence of contingent attention capture, whereas children with ASD showed no behavioral facilitation or alpha desynchronization to distractors that shared a task-relevant feature. Lastly, children with ASD had significantly decreased resting alpha power, and for all participants increased resting alpha levels were associated with greater task-related alpha desynchronization.ConclusionsThese results suggest that in ASD underresponsivity and impairments in orienting to salient events within their environment are reflected by atypical electroencephalography oscillatory neurodynamics, which may signify atypical arousal levels and/or an excitatory/inhibitory imbalance.