The Burden of occupational hearing loss (HL) is severe, having negative impacts on health care costs and quality of life. There is a strong Need to address barriers to wearing hearing protection devices (HPDs) that can prevent HL. This is especially true in regard to: (1) listening performance decrements that occur while wearing, and (2) the operational environments of first responders whose workplace conditions allow relatively little control over noise. This project will characterize HPD-related performance decrements, their impact on choice to wear HPDs, and how auditory training can be used as a means to alleviate decrements. Our innovative approach will use a paradigm where speech informs subjects to perform specific aspects of a sensorimotor task. This mimics critical communication scenarios in first responders (e.g., a firefighter given speech commands that inform her/his performance on another task). HPD listening will be simulated with a digital filter designed to mimic the attenuation profile of an actual HPD. Electroencephalographic (EEG) data will allow covert examination of neural signatures of ongoing cognitive processes. The approach will allow the characterization of HPD-related performance effects to a level of detail not achieved before, while at the same time maintaining research-to-practice relevance in the mapping of our experimental task to first responder operational situations. AIM 1 will characterize HPD-related decrements in performance. We expect that comparison of HPD and no HPD conditions will reveal the extent to which HPD use impacts multiple dimensions of performance (e.g., speech comprehension, sensorimotor task accuracy, and mental effort). AIM 2 will determine whether or not performance decrements impact choice to wear HPDs. Here, we will allow subjects to voluntarily toggle their simulated HPD on and off, while at the same time manipulating performance incentives to examine how listening difficulty impacts time spent "wearing" hearing protection. AIM 3 will test an auditory training approach to alleviating performance decrements. Here, we will compare effects of auditory training in HPD and no HPD conditions on multiple dimensions of performance. Aim 1 Impact will be in knowledge gains that cannot come from standard survey and focus group methods. The Impact of Aim 2 will be to provide an assessment of how performance decrements impact actual choice to wear. The Impact of Aim 3 will be to provide a means to address performance decrements in HL prevention programs (HLPPs). Relevant NIOSH strategic goals include goals to: "reduce occupational hearing loss", and inform "hearing loss prevention education for employers and workers". NORA sector groups of public safety, construction, and manufacturing have clear relevance. Outputs include publications and conference presentations at interdisciplinary venues that will accelerate research-to-practice directions. Outcomes entail new approaches to addressing HPD use r...