ABSTRACTTask‐dependent lateralization of the 40 Hz EEG rhythm was investigated in 15 right‐handed male adults during the performance of verbal analogy and geometric figure rotation tasks. Forty Hz EMG recorded from the temporal and splenius muscles was similarly examined. Results indicate that 40 Hz EEG is asymmetrically distributed during cognitive performance, varying as a function of cognitive processsing. The range of laterality scores also varied by condition, with the largest variation present during baseline conditions and smallest recorded during the presentation of the verbal analogies task, suggesting that individual cognitive styles tend to vary more during less structured situations. No relationship between 40 Hz EMG and task was obtai