Objective: We compared EEG coherence in children with and without AD/HD, and sought to relate
observed anomalies to AD/HD symptoms.
Methods: Forty children with AD/HD and 40 age- and sex-matched controls had eyes-closed resting EEG
coherence calculated for eight interhemispheric electrode pairs and eight intrahemispheric pairs (four
within each hemisphere) in the delta, theta, alpha, beta and ‘‘40 Hz’’ gamma bands.
Results: At short-medium inter-electrode distances, the AD/HD group had increased intrahemispheric
coherence in delta and theta, and reduced (L > R) laterality in delta, alpha, beta and gamma. Over longer
inter-electrode distances, the AD/HD group had reduced intrahemispheric coherence in alpha. In interhemispheric
comparisons, the AD/HD group had reduced frontal coherence in delta, alpha and gamma,
increased temporal theta and reduced temporal alpha coherences, and increased central/parietal/occipital
coherence in theta. Smaller left-lateralized coherences in AD/HD correlated negatively with DSM Inattentive
and DSM Total scores, and smaller frontal interhemispheric coherence in alpha correlated
negatively with DSM Hyperactive/Impulsive score.
Conclusions: The negative correlations between AD/HD coherence anomalies and symptoms suggest that
several anomalies reflect compensatory brain function.
Significance: Coherence differences in AD/HD may reflect anomalous frontal right-hemisphere linkages
that help compensate functional brain anomalies in the left frontal regions in this disorder.
2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd.