Phase Locking, Speech Perception In Noise, and Cognition In Tinnitus Patients With Normal Hearing

ABSTRACT Objective This study aims to evaluate the effects of tinnitus on extended high‐frequency (EHF) hearing thresholds, temporal fine structure (TFS) sensitivity, speech perception in noise (SPiN), and cognitive functions in individuals with normal hearing thresholds. Additionally, it aims to investigate the effects of tinnitus on central auditory mechanisms and cognitive functions by controlling for the influence of EHF hearing loss. Methods A total of 40 participants (19 tinnitus patients with normal hearing and 21 controls) were assessed. TFS sensitivity, SPiN, cognitive performance, and EHF hearing thresholds were evaluated using the TFS‐AF test, Turkish Matrix Test, RAVLT (Rey Auditory Verbal Learning Test), and audiometry, respectively. Results The tinnitus group showed significantly reduced TFS sensitivity ( p = 0.043), poorer SPiN performance ( p = 0.026), and lower RAVLT mean ( p = 0.008), RAVLT 6 ( p = 0.048), and RAVLT 7 ( p = 0.001) scores compared to controls. EHF thresholds were higher in the tinnitus group ( p = 0.032) and moderately negatively correlated with TFS sensitivity ( r = −0.32, p = 0.042). TFS sensitivity remained linked to SPiN performance after controlling for EHF hearing loss ( p = 0.048). Conclusion The results revealed that tinnitus patients were associated with higher EHF hearing thresholds, reduced TFS sensitivity, poorer SPiN performance, and difficulties in cognitive functions such as learning and memory. Higher EHF hearing thresholds appeared to be an important factor in the diminishing of these abilities. Furthermore, when the effect of EHF hearing thresholds was excluded, it was observed that reduced SPiN performance in tinnitus patients was associated with TFS sensitivity. Level of Evidence 4.