Relative changes in the cochlear summating potentials to paired-clicks predict speech-in-noise perception and subjective hearing acuity

Abstract

Objective assays of human cochlear synaptopathy have been equivocal. We posited relative changes in the cochlear summating potential (SP) may offer a superior biomarker for synaptic integrity. We recruited young, normal-hearing adults assigned to low- vs. high-risk groups based on their extended high-frequency (9-16 kHz) audiograms. SPs to paired-clicks with varying inter-click intervals isolated non-refractory receptor components of cochlear activity. We observed abrupt increases in SPs to paired- vs. single-clicks in high-risk listeners. Critically overexaggerated SP amplitudes also predicted speech-in-noise and subjective hearing abilities, suggesting relative SP changes to rapid clicks might help identify putative synaptopathic listeners with speech-listening difficulties.