Evoked potential correlates of left hemisphere dominance in covert articulation

Evoked Potentials (EPs) to a click stimulus were recorded at the temporal areas of both hemispheres of dextral subjects engaged in covert rehearsal of a verbal passage or in covert rehearsal of musical passages. A pattern of left hemisphere attenuation of the click EPs was observed in all subjects during speech rehearsal but not during music rehearsal. The implications of these findings for the issue of electroencephalographic localization of speech production mechanisms in the left hemisphere are discussed.