BINAURAL INTERACTION IN THE HUMAN BRAIN CAN BE NONINVASIVELY ACCESSEDWITH LONG-LATENCY EVENT-RELATED POTENTIALS

Invasive microelectrode measurements have demonstrated binaural intera ction effects of summation, occlusion, and suppression. Here we demons trate these phenomena in humans using non-invasive long-latency cortic al event-related potential (ERP) components N1 and mismatch negativity (MMN). Subjects were presented with monaural and binaural stimulus tr ains consisting of frequent standard stimuli and deviant stimuli devia ting from the standard either in frequency, intensity, or duration. Th e binaural N1 was smaller than the monaural N1. MMN for the intensity change was larger with binaural than monaural stimulation, whereas for the frequency and duration change, the MMN amplitude remained unchang ed. Thus, cortical binaural interactions reflected suppression in the N1, summation for the intensity MMN, and occlusion for the frequency a nd duration MMNs. (C) 1997 Elsevier Science Ireland Ltd.