The Role of Auditory Experience in the Neurocognitive Systems for Everyday and Effortful Listening

• Main Author: White, Bradley E
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01.01.2019
• Subjects: Audiology; Cognitive psychology; Neurosciences
• ISBN: 1392582210; 9781392582213

Current models of auditory cognition suggest that cognitive resources for processing challenging acoustic and linguistic information are limited, creating a trade-off between effort and comprehension. Indeed, everyday listening frequently occurs under a wide range of inescapable suboptimal and adverse conditions, challenges which are exacerbated by reduced hearing acuity and the use of imperfect hearing amplification and prosthetic devices. Using an assessment battery of hearing, listening, health status, intelligence, and language in combination with optical neuroimaging during a plausibility judgment task, we assess: (a) the effects of early-life sensitive windows on the neurocognitive mechanisms for everyday and effortful speech and language processing in response to early, life-long exposure to undegraded and acoustically-degraded speech and (b) the strength and nature of the relationships between physiological changes in hemodynamic activity in brain regions mediating effortful online speech and language processing and behavioral changes in task performance and perceived levels of expended mental effort for different listening conditions and cognitive demands. To advance these areas of scientific inquiry, we tested two competing hypotheses, the adaptive and effortful listening hypotheses. Using a combination of behavioral and neuroimaging analyses, we observe support for the effortful listening hypothesis. Findings reveal modulated online processing of everyday and eff ortful speech and language in early, life-long hearing aid and cochlear implant users and suggests: (a) greater initial and persistent contributions of cognitive executive functions than listeners with typical hearing, (b) modulated selectivity for effortful speech and language processing in the brain, and ( c) stronger brain-behavior correlations dissimilar to listeners with typical hearing that indicate the use of different attentional mechanisms. Ultimately, this work advances several scientific and societal questions regarding the role of deafness mediated by hearing technologies in certain cognitive functions, specifically online speech and language processing. These advancements could improve overall spoken language outcomes in those with hearing loss.