Speech enrichment: Listening effort and intelligibility
* Presenting author
In this study, we investigated differences between a hearing impaired (HI) and a normal hearing (NH) group on subjective, behavioural and neurophysiological measures of speech processing and listening effort. We fitted both groups with a hearing aid (HI for hearing loss compensation and NH with minimal amplification for comparison), and asked them to perform a speech-in-noise task. The target speech was presented in multi-talker babble noise in two SNRs (+5dB and 0dB). The hearing aid had three different settings: hearing loss compensation only, noise cancelling and beam forming. EEG (64 channels) was recorded during the experiment in order to analyse cortical entrainment as well was intersubject correlation. Results revealed a marked difference between cortical entrainment and other measures; whereas the subjective listening effort measure, behavioural performance (intelligibility) and intersubject correlation (as a measure of auditory attention) showed relatively small differences between the NH and the HI group, we found substantially larger cortical entrainment for the HI group, specifically in higher SNRs (+5dB). We suggest that these results might indicate effects of listening effort measurable specifically in the auditory processing stage.