Effect of deviant probability and interstimulus/interdeviant interval on the auditory N1 and mismatch negativity in the cat auditory cortex

In passive oddball paradigm the effects of changes in interstimulus/interdeviant interval (ISI; IDI) and deviant probability were investigated on mismatch negativity (MMN), auditory NI wave and the exogenous PI component of the auditory event-related potential in the cat. An epidural electrode matrix was chronically implanted over the auditory fields of the neccortex, and the amplitudes of the aforementioned components were measured in the location of their amplitude maxima. Dependence of the MMN both on the ISI and IDI as well as deviant probability was revealed, while the amplitude of the PI and NI showed dependence merely on the ISI. This method can be used for separation of the two negative, often overlapping components in the cat. (C) 2002 Elsevier Science B.V. All rights reserved.