Musical pitch and timbre perception deficits in tinnitus with normal hearing: the role of extended high-frequency sensitivity and spectral-temporal resolution.

In individuals with tinnitus, subtle changes in extended high-frequency (EHF) hearing and suprathreshold auditory processing may contribute to difficulties in complex auditory domains such as music perception. This study aimed to examine musical pitch and timbre perception, spectral-temporal resolution, and EHF hearing in normal-hearing individuals with and without tinnitus, while exploring the relationships among these measures. Individuals with bilateral tinnitus (n = 28) and without tinnitus (n = 28) were included, and all participants had normal conventional audiograms. Participants were administered the Pitch Direction Discrimination (PDD) and Timbre Recognition (TR) tests for pitch and timbre perception, the Adaptive Gap Detection Test (AGDT) for temporal resolution, and the Spectral-Temporally Modulated Ripple Test (SMRT) for spectral resolution. EHF thresholds were measured across the 9-18 kHz frequency range. Individuals with tinnitus exhibited significantly poorer performance across all measures compared to controls. After controlling for EHF, the group effect was no longer significant, and the covariate effect of EHF was also not significant. In the tinnitus group, PDD and TR were significantly associated with SMRT, AGDT, and EHF, and poorer suprathreshold performance was associated with greater tinnitus severity. Participants without residual inhibition also showed poorer suprathreshold performance. Within the tinnitus group, SMRT predicted PDD, whereas AGDT predicted TR. These findings indicate that tinnitus is associated with auditory encoding alterations that extend beyond pure-tone thresholds. EHF hearing appears to be associated with music perception through spectral and temporal mechanisms. Importantly, greater tinnitus severity may reflect broader alterations in suprathreshold auditory processing.