The role of cognitive functions in the hearing of speech-in-noise and the role of auditory and cognitive training in individuals’ speech-in-noise performance

Abstract

The most consistent determinant for any variation in speech-in-noise performance between individuals is their own audibility. There is, however, the potential that cognitive functions support listening when situations are challenging, such as when speech is being listened to in background noise. This research explores which cognitive functions support listening when speech is degraded in different manners, with working memory, speed of information processing, response latency and control of inhibition all indicating significant relationships. Based on these findings, both cognitive and auditory training was employed with participants to establish if this could demonstrate any improvement in both on-task performance, such that the task itself improved, and additionally if training could lead to changes in performance of other closely related (near transfer) or more loosely related (far transfer) tasks. There was no convincing evidence that cognitive training involving inhibition control and processing speed could lead to improved listening performance. Potentially, as cognitive functions play a more minor role in speech-in-noise performance when compared to audibility, training of these cognitive functions may need a more significant training input to demonstrate any significant change in speech-in-noise performance. There was, however, evidence that targeted auditory training may offer some advantages and that far transfer gains appear to be achievable and are most evident when the training material is highly challenging. When the role of a commercial communication training package involving both auditory and cognitive exercises was explored it gave very limited evidence of any significant advantage for first time hearing aid users over normal acclimitisation. Areas for future research are discussed, particularly with a view to training package development. Further, there is a discussion on how effective rehabilitation may lead to improved communication and the potential social and mental well-being that improved communication may bring.