Listening effort: The impact of simulated hearing loss on cognitive functions in young adults

Previous research has suggested that hearing loss significantly impacts cognition in both school-age children and the elderly (e.g. Hicks & Tharpe, 2002; Lin, 2011). This study is the first to report the potential cognitive impacts of simulated, mild hearing loss for a young adult population. The current study investigated the effect of simulated mild, highfrequency hearing loss on performance and effort in a sample of 43 young adults (aged 18- 23) who claimed to have normal hearing. On a standardized Speech-in-Nosie (SIN) Task, a significant effect of simulated hearing loss was found for both the sentence repetition accuracy, as well as the listening effort necessary to complete the task. Further, to test the interaction of cognitive load and hearing loss on accuracy and effort, participants completed a Memory Task under single- and dual-task conditions. While question response accuracy significantly decreased under dual-task conditions, accuracy was not significantly affected across hearing loss conditions. However, task effort was significantly increased in the simulated hearing loss condition. Analysis of order effects also suggested the employment of cognitive strategy, particularly in the SIN Task where the hearing conditions did not facilitate the recruitment of additional cognitive resources. All results are discussed from the standpoint of the Resource Allocation Hypothesis (Rabbitt, 1968). Overall, results suggested that mild hearing loss does negatively impact cognition and listening effort in young adults. However, young adults may be largely unable to detect this loss by themselves (Le Prell, Hensley, Campbell, Hall, and Guire., 2011; Widen, Holmes, Johnson, Bohlin and Erlandson., 2009). The Canadian healthcare system is also ill-equipped to detect such an impairment if it is not diagnosed in early childhood. Future research should place the spotlight on young adults to help remedy these problems