Occurrence of Mismatch Negativity in Response to Changes in the Durations of Short Pauses during Continuous Auditory Stimulation

Abstract

Mismatch negativity (MMN) is a component of the auditory evoked potential which is widely used in research and clinical investigations. Using the oddball paradigm, which is traditional for obtaining mismatch negativity, we recorded MMN-like responses to changes in the duration of short pauses (standard = 25 msec; deviant = 50 msec, and vice versa) on the background of continuous auditory stimulation (1 kHz, 50 dB). Our data show that this is the first description of this type of mismatch negativity. We compared the responses to changes in pause duration with “classical” mismatch negativity to changes in pause duration with the same time characteristics. Mismatch negativity to changes in pauses was characterized by longer latent periods and the absence of significant inversion in the mastoid leads. Both responses, to changes in sound duration and to changes in pause duration, demonstrated shorter latent periods when the deviants were longer than the standards as compared with the reverse situation. This new type of mismatch negativity may widen the potential for its use in clinical and research studies.