fNIRS, Listening Effort, and Motivation

Study Overview
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Brief Summary
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The purpose of the current study is to measure oxygenation in the PFC using fNIRS in a sample of older adults with hearing loss. Participants will be instructed to listen to sentences in noise at a challenging signal-to-noise-ratio, and to indicate what they heard using a closed-set response interface. Participants will complete 4 sessions: a training session, and a session for each condition. During each test session, participants will be instructed to listen to at least 100 sentences. Oxygenation, response times, and listening accuracy will be measured throughout.

Official Title
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Impacts of Hearing Aid Use on Listening Effort and Motivation Using fNIRS

Conditions
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Hearing Loss

Intervention / Treatment
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* Device: Hearing aids (omnidirectional)
* Device: Hearing aids (directional)
* Other: Unaided


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults (18-99) years Binaural, symmetrical, sensorineural N2 (mild) to N5 (moderate-severe) hearing loss Experienced hearing aid users Fluent in English Exclusion Criteria: Minors (17 years or less) Hearing status that did not fall within inclusion criteria Vulnerable populations

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Hearing loss<br>All participants will have hearing loss and be assigned to all three interventions. The interventions consist of aided-omnidirectional, aided-directional, and no hearing aids (no intervention). | Device: Hearing aids (omnidirectional)<br>* Device for hearing loss compensation with microphone sensitivity all around the listener.<br>Device: Hearing aids (directional)<br>* Device for hearing loss compensation with microphone sensitivity in front of the listener.<br>Other: Unaided<br>* Control condition<br>* Other names: No hearing aids;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygenation using functional near infrared spectroscopy (fNIRS) | Infrared light scattered from the prefrontal cortex, which is indicative of concentration of oxygenated blood in that region. fNIRS in the prefrontal cortex is intended to index both motivation and listening effort. | Up to 1 hour during 1 session (per condition - for a total of 3 hours) | 
| Response times | Response times will be defined as the amount of time between the beginning of a stimulus and when participants submit their responses. | Up to 1 hour during 1 session (per condition - for a total of 3 hours) | 
| Listening accuracy | Speech understanding in noise percent correct scores | Up to 1 hour during 1 session (per condition - for a total of 3 hours) |