Mismatch response of the human brain to changes in sound location

WE Investigated whether the enhanced negativity of the human event-related brain potential elicited by changes in auditory lateralization is due to a higher-order change-detection process or whether it can be explained exclusively in terms of selective sensory adaptation. Infrequent changes in lateralization of a repetitive standard tone, generated by changes in interaural time differences, elicited a frontocentrally distributed negative brain wave in the 100–250 ms range relative to stimulus onset. This brain wave was also elicited when possible sensory adaptation was prevented by controlling for the state of refractoriness of location-specific neurones. The results demonstrate that changes in lateralization elicit a genuine mismatch negativity (MMN), indicating the activity of an automatic higher-order change-detection process.