Individual similarities and differences in eye-movement-related eardrum oscillations (EMREOs)

Hear Res. 2023 Oct 30;440:108899. doi: 10.1016/j.heares.2023.108899. Online ahead of print.ABSTRACTWe recently discovered a unique type of otoacoustic emission (OAE) time-locked to the onset (and offset) of saccadic eye movements and occurring in the absence of external sound (Gruters et al., 2018). How and why these eye-movement-related eardrum oscillations (EMREOs) are generated is unknown, with a role in visual-auditory integration being the likeliest candidate. Clues to both the drivers of EMREOs and their purpose can be gleaned by examining responses in normal hearing human subjects. Do EMREOs occur in all individuals with normal hearing? If so, what components of the response occur most consistently? Understanding which attributes of EMREOs are similar across participants and which show more variability will provide the groundwork for future comparisons with individuals with hearing abnormalities affecting the ear's various motor components. Here we report that in subjects with normal hearing thresholds and normal middle ear function, all ears show (a) measurable EMREOs (mean: 58.7 dB SPL; range 45-67 dB SPL for large contralateral saccades), (b) a phase reversal for contra- versus ipsilaterally-directed saccades, (c) a large peak in the signal occurring soon after saccade onset, (d) an additional large peak time-locked to saccade offset and (e) evidence that saccade duration is encoded in the signal. We interpret the attributes of EMREOs that are most consistent across...
Source: Hearing Research - Category: Audiology Authors: Source Type: research