HESP Seminar: Evaluating the Importance of Self-Perceived Temporary Threshold Shifts
Tuesday, February 28, 2023
11:00 a.m.-12:00 p.m.
2208 LeFrak Hall
Title: "Evaluating the Importance of Self-Perceived Temporary Threshold Shifts"
Speaker: Jaclyn Schurman (Walter Reed National Military Medical Center)
Abstract: Noise exposure limits set by the Occupational Safety and Health Administration (OSHA), National Institute for Occupational Safety and Health (NIOSH) and the Army’s Hearing Conservation Program were designed to prevent individuals from experiencing a permanent threshold shift, but these regulations were not intended to prevent a temporary threshold shift. Previous animal studies have established that permanent damage to the auditory system can occur even when hearing thresholds return to baseline after a temporary threshold shift. Therefore, it is essential to better understand the impact of lifetime temporary threshold shifts on the human auditory system. The purpose of this work is to evaluate the influence of self-perceived temporary threshold shifts on objective measures of auditory function and subjective reports of hearing difficulty. Approximately 12,000 U.S. Service Members completed questionnaires and auditory assessments in conjunction with their annual hearing conservation exam. Data collected from each participant included pure-tone audiometric thresholds, a tone detection task, a speech intelligibility measure, a survey of self-reported hearing difficulty, and a question regarding how often individuals experienced a temporary threshold shift after a noise exposure event. Results showed that Service Members who never experienced a hearing change after a noise exposure event performed better on objective measures of auditory function and reported less difficulty hearing compared to individuals who reported more frequent temporary threshold shifts. The results indicate that frequent temporary threshold shifts may be a risk factor for developing subjective and objective hearing difficulties. The results also have important implications for hearing conservation programs and noise exposure education for the general public. Individuals reporting frequent temporary threshold shifts may need additional assessment, education, and intervention.