IALP 2025

Effects of wearing closed or noise-cancelling earplugs on listening in noisy environments

Chie Obuchi
Institute of Human Sciences, University of Tsukuba, Japan

Objective: Individuals with listening difficulties or auditory processing disorder (LiD or APD) experience difficulties when listening to speech in noisy environments. Some individuals complain of auditory hypersensitivity to sounds as well as difficulty listening to speech, and prefer to wear earmuffs or earplugs rather than use an assistive listening device. There is no evidence that wearing earplugs is effective for individuals with LiD. In this study, we investigated the effectiveness of wearing earplugs when listening to speech in noisy situations for individuals with normal hearing.

Method: Sixteen individuals with normal hearing and no listening difficulties were included. The Hearing in Noise Test Japanese (HINT-J) was used to assess their listening abilities under three conditions: when wearing closed-type earplugs, noise-cancelling earplugs, and no earplugs. HINT-J scores were an objective assessment indicator, and listening effort and loudness were subjective assessment indicators. We statistically compared the results between earplug conditions using the Friedman test.

Results: There were significant differences between the HINT-J scores (χ2=10.70, p<0.01) and the loudness scores (χ2=9.12, p<0.05): the scores for the no-earplug condition were significantly higher than the other earplug conditions. However, there were no significant differences between earplug conditions for listening effort scores (χ2=1.66, n.s.).

Discussion: Using earplugs (even noise-cancelling earplugs) had no effect on objective listening performance when listening to speech in noisy situations. However, there were no differences in subjective listening effort, suggesting that people have subjective listening impressions and tend to decide whether or not to use earplugs based on these impressions, regardless of objective scores. In future studies, we plan to clarify the differences between subjective listening effort and objective listening scores.