Multi-frequency Electrophysiological Estimates of Auditory Temporal Acuity
Abstract
Auditory temporal acuity, a listener’s ability to discriminate rapid changes in the envelope of an auditory signal over time, is crucial for understanding speech. Electrophysiological measurement of auditory temporal acuity is beneficial when we cannot achieve reliable behavioural responses. The envelope following response (EFR) evoked by a changing (swept) amplitude-modulated (AM) stimulus is significantly correlated with behavioural measures of temporal acuity in humans. Previous research using AM broadband noise carriers may have been affected by the cancellation of evoked potentials at the measurement electrodes due to out-of-phase interference of parallel responses initiated at different times due to cochlear travelling wave timing differences. This study aimed to examine the possibility of using narrow-band noise carriers with different center frequencies, which enables recording of EFR from low, mid and high-frequency cochlear regions individually, while the modulation frequency gradually varied over time, and to determine whether we can improve the previously proposed objective method in three groups of normal-hearing participants.
Keywords
Electrophysiological measurements, temporal acuity, envelope following response (EFR), narrow-band noise carrier, normal hearing adults