Speech-in-noise perception in unilateral hearing loss: relation to pure-tone thresholds and brainstem plasticity

Publication date: Available online 13 June 2017 Source:Neuropsychologia Author(s): Nicolas Vannson, Chris J. James, Bernard Fraysse, Boris Lescure, Kuzma Strelnikov, Olivier Deguine, Pascal Barone, Mathieu Marx We investigated speech recognition in noise in subjects with mild to profound levels of unilateral hearing loss. Thirty-five adults were evaluated using an adaptive signal-to-noise ratio (SNR50) sentence recognition threshold test in three spatial configurations. The results revealed a significant correlation between pure-tone average audiometric thresholds in the poorer ear and SNR thresholds in the two conditions where speech and noise were spatially separated: dichotic – with speech presented to the poorer ear and reverse dichotic – with speech presented to the better ear. This first result suggested that standard pure-tone air-conduction thresholds can be a reliable predictor of speech recognition in noise for binaural conditions. However, a subgroup of 14 subjects was found to have poorer-than-expected speech recognition scores, especially in the reverse dichotic listening condition. In this subgroup 9 subjects had been diagnosed with vestibular schwannoma at stage III or IV likely affecting the lower brainstem function. These subjects showed SNR thresholds in the reverse dichotic condition on average 4dB poorer (higher) than for the other 21 normally-performing subjects. For the 7 of 9 subjects whose vestibular schwannoma was removed, the deficit wa...

Source: Neuropsychologia - June 14, 2017 Category: Neurology Source Type: research