Competition between cortical ensembles explains pitch-related dynamics of auditory evoked fields

Abstract

The latency of the N100m transient component of the magnetic auditory evoked fields presents a widely reported correlation with perceived pitch. These observations have been robustly reproduced in the literature for a number of different stimuli, indicating that the neural generator of the N100m has an important role in cortical pitch processing. In this work, we introduce a realistic cortical model of pitch perception revealing, for the first time to our knowledge, the mechanisms responsible for the observed relationship between the N100m and the perceived pitch. The model describes the N100m deflection as a transient state in cortical dynamics that starts with the incoming of a new subcortical input, holds during a winner-takes-all ensemble competition, and ends when the cortical dynamics reach equilibrium. This model qualitatively predicted the latency of the N100m of three families of stimuli.