Differential hemispheric activation during complex visuomotor performance.

Bilateral EEGs were recorded from central, temporal and parietal scalp locations from seven male and seven female human subjects (Ss) while they were engaged in verbal and non-verbal tasks. Alpha power was higher in the right hemisphere when Ss listened to verbal material being read to them; the reverse was true when Ss performed in an imaginative block rotation task. Compared with intergame rest periods, alpha power was suppressed in the right hemisphere when Ss either watched or played Pong (TV tennis). Watching Pong was as effective in producing in producing alpha asymmetry as playing the game in the parietal region, but motor involvement enhanced asymmetry at central and temporal leads. Performance was non-linearly related to asymmetry, first increasing and then decreasing as asymmetry increased.