Both frequency and interaural delay affect event-related potential responses to binaural gap.

Human listeners are extraordinarily sensitive to a transient break in interaural correlation (called binaural gap). In this study, a binaural gap embedded in interaurally correlated noise markers elicited marked scalp event-related potentials (ERPs). ERPs to the binaural gap in narrowband noise with the center frequency of 1600 Hz were significantly weaker than those for narrowband noise with the center frequency of 400 or 800 Hz. Introducing the interaural time difference (ITD) of 4 ms weakened the ERPs for either 400-Hz or 800-Hz noise. Introducing the ITD of 2 ms, however, only weakened the ERPs for 800-Hz but not 400-Hz noise. Thus central representations of a transient break in interaural correlation for narrowband noises are affected by both frequency and ITD.