Behavioral characterization of the cochlear amplifier lesion due to loss of function of stereocilin (STRC) in human subjects

Hear Res. 2023 Nov;439:108898. doi: 10.1016/j.heares.2023.108898. Epub 2023 Oct 20.ABSTRACTLoss of function of stereocilin (STRC) is the second most common cause of inherited hearing loss. The loss of the stereocilin protein, encoded by the STRC gene, induces the loss of connection between outer hair cells and tectorial membrane. This only affects the outer hair cells (OHCs) function, involving deficits of active cochlear frequency selectivity and amplifier functions despite preservation of normal inner hair cells. Better understanding of cochlear features associated with mutation of STRC will improve our knowledge of normal cochlear function, the pathophysiology of hearing impairment, and potentially enhance hearing aid and cochlear implant signal processing. Nine subjects with homozygous or compound heterozygous loss of function mutations in STRC were included, age 7-24 years. Temporal and spectral modulation perception were measured, characterized by spectral and temporal modulation transfer functions. Speech-in-noise perception was studied with spondee identification in adaptive steady-state noise and AzBio sentences with 0 and -5 dB SNR multitalker babble. Results were compared with normal hearing (NH) and cochlear implant (CI) listeners to place STRC-/- listeners' hearing capacity in context. Spectral ripple discrimination thresholds in the STRC-/- subjects were poorer than in NH listeners (p < 0.0001) but remained better than for CI listeners (p < 0.0001). Freque...
Source: Hearing Research - Category: Audiology Authors: Source Type: research