TEMPORAL WINDOW OF INTEGRATION OF AUDITORY INFORMATION IN THE HUMAN BRAIN

A deviation in the acoustic environment activates an automatic change- detection system based on a memory mechanism that builds a neural trac e representing the preceding sounds. The present study revealed that t he auditory-cortex mechanisms underlying this sensory memory integrate acoustic events over time, producing a perception of a unitary audito ry event. We recorded magnetic responses (MMNm) to occasional stimulus omissions in trains of stimuli presented at a constant stimulus-onset asynchrony (SOA) that was, in different blocks, either shorter or lon ger in duration than the assumed length of the temporal window of inte gration. A definite MMNm was elicited by stimulus omission only with t he three shortest SOAs used: 100, 125, and 150 ms, but not with 175 ms . Thus, 160-170 ms was estimated as the length of the temporal window used by the central auditory system in integrating successive auditory input into auditory event percepts.