The middle ear muscle reflex: Current and future role in assessing noise-induced cochlear damage

Abstract

The middle ear muscle reflex (MEMR) in humans is a bilateral contraction of the middle ear stapedial muscle in response to moderate-to-high intensity acoustic stimuli. Clinically, MEMR thresholds have been used for differential diagnosis of otopathologies for decades. More recently, changes in MEMR amplitude or threshold have been proposed as an assessment for noise-induced synaptopathy, a subclinical form of cochlear damage characterized by suprathreshold hearing problems that occur as a function of inner hair cell (IHC) synaptic loss, including hearing-in-noise deficits, tinnitus, and hyperacusis. In animal models, changes in wideband MEMR immittance have been correlated with noise-induced synaptopathy; however, studies in humans have shown more varied results. The discrepancies observed across studies could reflect the heterogeneity of synaptopathy in humans more than the effects of parametric differences or relative sensitivity of the measurement. Whereas the etiology and degree of synaptopathy can be carefully controlled in animal models, synaptopathy in humans likely stems from multiple etiologies and thus can vary greatly across the population. Here, we explore the evolving research evidence of the MEMR response in relation to subclinical noise-induced cochlear damage and the MEMR as an early correlate of suprathreshold deficits.

Perceptual Consequences of Cochlear Deafferentation in Humans

“… Van Der Biest et al (2023) reviewed the complexities involved in translating EFR measurements from animal models to humans and used a computational model of the human auditory periphery to predict which EFR stimulus parameters will be the most effective for estimating cochlear synapse loss. The MEMR is an auditory-evoked reflex resulting in frequency-specific changes in middle ear impedance and is mediated by a reflex pathway that includes the cochlea and auditory nerve (see review by Trevino et al, 2023 for a discussion of the use of the MEMR as a measure of synaptopathy). Note that two different methods of measuring the MEMR have been used in human studies.…”

Accuracy and Repeatability of ChatGPT Based on a Set of Multiple-Choice Questions on Objective Tests of Hearing

“…This study aims to fill these gaps by assessing the accuracy and repeatability of ChatGPT versions 3.5 and 4 in answering test questions about the physiology of hearing. Objective measures such as tympanometry [13], middle ear muscle response [14], otoacoustic emissions [15], and auditory brainstem responses [16] are paramount in audiology and here they served as the basis for our investigation. By focusing on the shortterm repeatability of responses -within a single day, across two days, and over a week -this study sought to determine the feasibility of deploying ChatGPT in a clinical audiology setting, evaluating its potential as a reliable diagnostic or educational aid.…”