Noise Exposure and Near-Infrared Light

Study Overview
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Brief Summary
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The primary objective of this work is to determine the effect noise has on the auditory system (both auditory health and performance) and also the degree to which the effect of pre-noise therapy such as Near Infrared (NIR) light can mitigate the effects of noise exposure.

Official Title
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Effects of Noise Exposure and Near Infrared Light (NIL) on Auditory Health and Performance

Conditions
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Hearing Loss, Noise-Induced

Intervention / Treatment
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* Device: Near Infrared Light
* Other: Noise Stimulus
* Device: Sham Near Infrared Light


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-45 years old, male or female Pass hearing exam with a threshold of 25 decibels (dB) hearing or less, for each ear, for all frequencies tested from 500 Hz to 8000 Hz Normal otoscopic exam, otoacoustic emissions (OAEs), and middle ear function as demonstrated by a normal tympanogram Completion of a hearing history questionnaire Exclusion Criteria: Screening hearing test failure Pregnant females Adults unable to provide consent History of significant ear surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Noise Stimulus and Infrared Light<br>All participants will receive noise stimulus at each of the 4 visits. In addition, they will receive infrared light therapy for 2 out of the 4 visits and sham infrared light therapy for the other 2 visits. | Device: Near Infrared Light<br>* NIR Light Therapy will be administered with the Earlight Generation 1.4 device during 2 out of the 4 sessions. It will be administered to each ear individually for 30 minutes per ear.<br>Other: Noise Stimulus<br>* Noise stimulus will be administered, open ear, to continuous broadband noise up to 25% of the allowable daily dose of noise per the AFI 48-127 Occupational Noise and Hearing Conservation Program.<br>|
| Sham Comparator: Noise Stimulus and Sham<br>All participants will receive noise stimulus at each of the 4 visits. In addition, they will receive sham infrared light therapy for 2 out of the 4 visits and infrared light therapy for the other 2 visits. | Other: Noise Stimulus<br>* Noise stimulus will be administered, open ear, to continuous broadband noise up to 25% of the allowable daily dose of noise per the AFI 48-127 Occupational Noise and Hearing Conservation Program.<br>Device: Sham Near Infrared Light<br>* Sham NIR Light Therapy will be administered with the Earlight Generation 1.4 device during 2 out of the 4 sessions. It will be administered to each ear individually for 30 minutes per ear.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in auditory threshold | Auditory function tests will be measured through the change in air conduction threshold measurements from 500 up to 8000 Hz | Baseline, up to 365 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in otoacoustic emissions (OAE) | Auditory performance will be measured through OAE testing | Baseline, up to 365 days | 
| Change in central auditory performance (CAP) | Auditory performance will be measured through central auditory processing assessments | Baseline, up to 365 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Noise induced hearing loss, Near infrared energy, Hering test