1 Project Summary / Abstract 2 People with hearing impairment report listening effort as a major barrier to successful social communication 3 (Hughes et al. 2018), with increases in effort leading to increases in anxiety (Morata et al. 2005), early retirement 4 (Danermark & Gellerstedt 2004), changes in social behavior and negative self-image (Hétu et al. 1988), and 5 listening-related fatigue (Edwards, 2007). Fatigued adults have been shown to be less productive in the 6 workplace, with increases in work absences, more errors and accidents than those not suffering from fatigue 7 (Ricci et al. 2007; Williamson et al. 2011), and workers with hearing loss taking more sick leave due to complaints 8 of “mental distress” (Kramer et al., 2006). Therefore, it is critical to understand what aspects of communication 9 are effortful for listeners with hearing impairment, and the ways that sustained effort leads to accumulated mental 10 fatigue. Previous work has mostly examined listening effort and fatigue separately, with vastly different 11 experimental methods and designs, leaving the mechanistic connection between effort and fatigue unknown. 12 This project is designed to address that need by expanding on previous work to explore whether the same 13 mechanisms that contribute to listening effort are merely episodic, or whether they directly contribute to 14 accumulated fatigue. One of the primary mechanisms of listening effort is mentally repairing misperceived words 15 when perceiving speech; using context to retroactively repair earlier misperceptions is effortful (Winn & Teece 16 2021), yet the same context when used predictively can reduce effort (Winn 2016). The aims of this project are 17 to 1) identify how reliance on cognitive repair to recover misperceptions affects listening effort, and 2) directly 18 measure the impact of sustained effortful listening on accumulated fatigue. The first aim will result in identifying 19 the time-course of effort when repairing early versus later misperceived words. Importantly, these results will 20 show how effort is sustained during language processing, potentially for several seconds after sentence offset. 21 The second aim will explore whether momentary increases in effort accumulate to fatigue, which will be 22 measured physiologically (pupillometry) and behaviorally (reaction time). The long-term goals of this project are 23 to improve our understanding of what makes listening effortful for people with CIs and to understand whether 24 the same mechanisms that contribute to listening effort also contribute to fatigue or are merely episodic increases 25 in effort. These goals directly address the NIDCD’s priority of increasing our knowledge of the mechanisms of 26 the cognitive processes needed for successful communication in more real-world environments. The training 27 program involves extensive instruction in behavioral measures, pupillometry, and advanced statistical analysis 28 relevant to the...