A Lateral Inhibition Mechanism Explains the Dissociation between Mismatch Negativity and Behavioral Pitch Discrimination.

A Lateral Inhibition Mechanism Explains the Dissociation between Mismatch Negativity and Behavioral Pitch Discrimination.
Brain Res. 2019 Jun 24;:146308
Authors: Gu F, Wong L, Hu A, Zhang X, Tong X
Abstract
Although mismatch negativity (MMN), a change-specific component of auditory event-related potential, is considered to be an index of sound discrimination accuracy, the amplitude of the MMN responses elicited by pitch height deviations in musicians and tone language speakers with superior pitch discrimination is usually not enhanced compared to that elicited in individuals with inferior pitch discrimination. We hypothesized that superior pitch discrimination is accompanied by enhanced lateral inhibition, a critical neural mechanism that sharpens the tuning curves of the auditory neurons in the tonotopy. Forty Mandarin-speaking healthy adults completed an auditory EEG experiment in which MMN was elicited by pitch height deviations in both pure and harmonic tones. Their behavioral pitch discrimination was indexed by the difference limens measured using pure and harmonic tones. Behavioral pitch discrimination correlated significantly with the MMN elicited by pure tones, but not by harmonic tones; this could be due to lateral inhibition strongly influencing the MMN elicited by harmonic tones but having less effect on the MMN elicited by pure tones. As lateral inhibition is a neural mechanism for attenuating the amplitude of MMN, our re...

Source: Brain Research - June 23, 2019 Category: Neurology Authors: Gu F, Wong L, Hu A, Zhang X, Tong X Tags: Brain Res Source Type: research