Abstract:
Objective: To investigate whether improvements to the auditory processing (AP) system are responsible for the reduced acceptable noise levels (ANLs) after a period of auditory training. Background: A form of auditory training named the Auditory Object Identification and Localisation (AOIL) task has previously shown to be beneficial through its improvement of people’s willingness to tolerate background noise. A previous study by Bees, (2016) identified the task as a method of reducing the ANLs in young adults with normal hearing. No measures of AP had previously been assessed alongside the training to identify whether it is responsible for this improvement in the ANL. However, previous studies have questioned whether it could be related to attentional mechanisms. This study will be the first to assess the AP pathways during the training task and will explore the possibilities of these pathways being altered. Method: Twenty adults with normal or near normal peripheral hearing underwent audiological assessments and measures of AP at 3 different stages in a cross-over design. Each of the three sessions involved tests of AP as well as ANL testing to determine whether there were any significant changes to their performance in the tests. The participants formed 2 groups, with one group starting the training in the first 2 weeks and the other starting in the following 2 weeks. Differences between their AP and ANLs were investigated to determine if there was an effect of training on their performance. Results: Significant improvements in the willingness to tolerate or accept background noise were measured via ANL testing following a period of 2 weeks with the AOIL training and was compared to a baseline measure and 2 weeks of no training. The significant change responsible for the improved ANL was the increased background noise level. No significant changes in to the AP pathways were observed via the dichotic digit’s test, frequency pattern test, random gap detection test and listening in spatialized noise test. Conclusion: AOIL auditory training is an effective method of treatment to increase tolerance of background noise. The mechanism behind this improvement remains unknown. Although AP systems were assessed, no changes to AP were observed. This research suggests a mechanism independent of AP as assessed using the tests described; the underlying process responsible for the improvement in ANL with training remains to be ascertained.