Evidence of Cortical Changes in Those with Hearing Loss

A novel test design has unlocked evidence of cortical changes in those with hearing loss, not age related.

A group of researchers investigated differences in the temporal processing of natural speech stimuli in a group of hearing-impaired subjects to an age-matched control group with normal hearing. This new measure is called “f0-tracking.” Both subcortical and cortical responses were captured using a male speaker dialog as the stimulus. Smaller responses, indicating less cortical activity, were found in older subjects without hearing loss. However, larger responses in another area of the recording were found in subjects with more severe hearing loss as compared to their age-matched peers, consistent with hearing-loss induced cortical reorganization and the addition of other neural structures to help with speech perception.

This study offers further proof of cortical reorganization in hearing impaired adults. Clinically, many patients report a decrease in understanding speech before any significant loss is captured on the pure tone audiogram. Evaluating their cortical responses, similar to the strategy used in this study, may be of value in identifying cortical changes in these patients. Full article included with the reference below.

Reference

Van Canneyt J, Wouters J, Francart T. (2021) Cortical compensation for hearing loss, but not age, in neural tracking of the fundamental frequency of the voice. J Neurophysiol 126: 791-802.