Methylphenidate effects on global and complex measures of EEG

Methylphenidate (MPH) effects on global and complex measures of electroencephalography were examined in boys with attention-deficit-hyperactivity disorder between the ages of 9 and 11 years. Electroencephalogram (EEG) data were collected separately from the administration of a continuous performance task and were evaluated for changes in overall frequency, coherence, phase, and asymmetry and against a referential database. MPH did not produce a clear change in EEG frequency measures compared with the task condition, although it did induce regional changes in the EEG and produced an improvement in task performance. In comparison against the referential database, MPH appeared to lessen the impact of abnormalities in EEG coherence, EEG phase, and EEG asymmetry on performance measures.