Cortical Auditory Evoked Potentials of Children with Normal Hearing Following a Short Auditory Training with a Remote Microphone System

Abstract

Remote microphone (RM) systems are assistive listening devices that improve the signal-to-noise ratio (SNR) to the user, facilitating children’s speech perception in noisy environments. As a result, these devices are widely used by children in environments in which there are high levels of background noise (e.g., school). However, the impact that RM system use has at the cortical level is still unknown. In the present project, we investigated whether a brief speech-in-noise training with an RM system had an impact on cortical auditory evoked potentials (CAEPs) and speech-in-noise perception skills of children with normal hearing. Two groups of school-age children participated in the study. One group received training with the RM system and the other group received training without the RM system. Speech-evoked CAEPs and behavioral speech-in-noise abilities were tested pre- and post-training in all children. Results showed that children who received training with the RM system had increased cortical activity (reflected by greater modulations in the strength of the response and higher amplitudes in the N2 response time-window) post-training compared to pre-training. Children receiving training without the RM system did not show any change in cortical activity post-training. However, children from both groups demonstrated equivalent improvement on speech-perception-in-noise skills post-training compared to pre-training. These results suggest that listening at an improved SNR via an RM system might induce neuroplastic changes in children with normal hearing, potentially facilitating speech categorization at the cortical level. It is likely that the brief training was insufficient to allow us to capture differential training effects at the behavioral level. Future studies will investigate whether longer trainings or long-term experience with an RM system can not only produce changes at the cortical level but also improve children’s ability to encode speech in the presence of background noise.