The Relationship Between Recreational Noise Exposure and Masking Release Thresholds in Individuals with Normal Hearing

Abstract

Background: With increasing technological advancements and widespread use of Personal Music Players (PMPs), especially among young adults and teenagers, prolonged exposure to high sound levels has become common. Such exposure is associated with subtle, progressive damage to the auditory system, particularly the synapses between inner hair cells and auditory nerve fibers, termed hidden hearing loss. This condition often goes undetected by standard audiological tests but may impact everyday listening. Therefore, there is a growing need for sensitive measures to identify early auditory deficits linked to noise-induced synaptopathy. Masking Release (MR), the ability to detect signals in intermittent versus continuous background noise, relies on precise neural timing and is thought to reflect the integrity of auditory nerve function. Thus, the present study examined the relationship between recreational noise exposure and masking release thresholds in individuals with clinically normal hearing. Method: Participants aged 18–30 were divided into two groups based on their recreational noise exposure using the Noise Exposure Structured Interview (NESI) (Guest et al., 2018): Group A (Control, <1 UNE) and Group B (Exposed, >1 UNE). Extended High-Frequency (EHF) audiometry, Distortion Product Otoacoustic Emissions (DPOAEs), and Masking Release (MR) Thresholds were administered, and results were statistically analyzed. Results: Individuals with higher recreational noise exposure showed significantly reduced masking release ability, indicating difficulty using temporal dips in background noise. However, EHF thresholds and DPOAE amplitudes did not differ significantly between groups, suggesting preserved peripheral cochlear function. Correlational analysis showed modest associations between MR thresholds and both EHF thresholds (particularly at 11200–12500Hz) and mid-to-high frequency DPOAEs (6000–8700 Hz), especially under challenginglistening conditions (60 dB SPL, 0 dB SNR), hinting at subtle cochlear changes. Conclusion: Temporal masking release is a sensitive behavioral marker of suprathreshold auditory deficits associated with recreational noise exposure, despite normal audiometric and DPOAE results. These findings support growing evidence for noise-induced synaptopathy and highlight the need for advanced diagnostic tools. Given its non-linguistic nature and real-world relevance, MR is a promising addition to routine audiological evaluations, particularly for early detection and prevention in high-risk populations such as regular PMP users.