Seminars in Hearing Research

Date: Thursday, April 17, 2025

Location: Nelson 1215

Time: Noon - 1:00 pm

Speaker: Taylor Alexis Teague, Undergraduate Student, SLHS  

Title: Time-compressed discourse comprehension in young and older adults: behavioral and neuroimaging analyses.

Abstract: Purpose: Real-world communication, also known as discourse comprehension, requires more complex cognitive-linguistic processing than the brief, isolated sentences typically used in the audiology clinic. Assessing discourse comprehension provides a more ecologically valid approach to quantify an individual’s communication abilities. This study examined the cognitive factors, such as working memory and temporal processing speed, involved in speech comprehension among younger and older adults when listening to speech stimuli that simulated challenging real-world communication conditions. We hypothesized that age-related declines in working memory and temporal processing speed would negatively impact comprehension ability.

Methods: Behavioral and neuroimaging measures assessed discourse comprehension in 40 normal-hearing participants (20 younger adults 19-27 years, 20 older adults 55+ years). Participants listened to ten short-story narratives that were time compressed to simulate a rapid rate of speech. Listeners were instructed to answer yes-or-no comprehension questions of varying difficulty. Functional near-infrared spectroscopy (fNIRS) was used to measure brain activation in auditory and cognitive regions during the comprehension task. Cognition was evaluated using the Montreal Cognitive Assessment (MoCA) and subtests from the Wechsler Adult Intelligence Scale (WAIS-IV).

Results: fNIRS data revealed distinct neural activation patterns between younger and older adults across comprehension-question types, highlighting differences in cognitive strategies for discourse processing. Older adults employ brain regions associated with higher-order language processing and processing speed, while younger adults engage regions associated with decision-making and working memory functions. Behavioral results revealed changes in comprehension accuracy and response times between age groups when answering inference-based questions. Better scores on the WAIS cognitive assessments in working memory capacity and temporal processing speed yielded better accuracy percentages, as well as lower changes in response times.

Implications: These results highlight the critical role of cognition in discourse processing, particularly in aging populations. The distinct neural activation patterns observed between younger and older adults suggest that different cognitive strategies are potentially shaped by age-related changes in working memory and processing speed. Those processing strategies affect how individuals comprehend inference-based questions in real-world listening scenarios. Older adults' reliance on higher-order language regions may indicate compensatory mechanisms in response to declines in temporal processing speed or working memory. Recognizing the role of cognition is essential for developing more ecologically valid assessments and interventions that truly reflect the challenges older adults face in everyday communication.

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The working schedule is available here: https://purdue.edu/TPAN/hearing/shrp_schedule

The titles and abstracts of the talks will be added here: https://purdue.edu/TPAN/hearing/shrp_abstracts