The Effects of Noise on Speech Intelligibility in Normal Hearing Workers Exposed to Noise in Professional Life

Objectives: In individuals with prolonged background noise exposure and those with peripheral auditory problems, central auditory disorders and cognitive impairments are observed. This study aims to evaluate individuals with and without noise exposure via the Matrix test to reveal concrete indicators of noise effects that are not reflected in pure-tone audiometry results. Material and Methods: The study included 40 participants between the ages of 22 and 45 with and without a history of noise-exposure divided into control and study groups (n = 20 per group). All participants were administered pure-tone audiometry with high-frequency, speech audiometry, tympanometry, and Matrix tests. The Matrix test performed adaptive measurements in the open-set response format; the participant verbally repeated all the words from a presented sentence. Results: In the tests performed on the study and control groups, no significant difference was found between the two groups except for the Matrix test. Conclusions and Significance: Although the audiological results of the individuals exposed to noise were considered normal, their speech discrimination ability in noise deteriorated. Even individuals with normal hearing thresholds in pure-tone audiometry could have trouble with speech discrimination in noisy everyday environments. While evaluating these individuals, testing speech discrimination in noise is critical to show problems in daily life.