Cochlear Synaptopathy and Hidden Hearing Loss: Mechanisms, Diagnosis, and Therapeutic Directions

Many people report real difficulty following speech in noisy settings while their standard audiogram comes back normal. A growing body of work links this “hidden hearing loss” to cochlear synaptopathy, the loss or dysfunction of the synapses between inner hair cells and auditory nerve fibers. Because these synapses can be damaged well before hair cells die or thresholds shift, conventional pure-tone audiometry often misses the problem entirely. Animal studies have shown that noise exposure, aging, and ototoxic agents can cause substantial synaptic loss without permanent threshold changes, and emerging human evidence points in the same direction. Despite this progress, the field still lacks a clear picture of how synaptopathy develops across different causes, how it relates to everyday listening difficulty, and how to detect it reliably in the clinic. Translating mechanistic insight into validated tests and treatments remains the central unmet need.GoalThis Research Topic aims to bring together current research on the mechanisms, diagnosis, and treatment of hidden hearing loss and cochlear synaptopathy. We hope to connect fundamental work on synaptic damage and repair with the clinical challenge of identifying patients whose hearing complaints are not explained by the audiogram. By uniting perspectives from auditory neuroscience, audiology, otology, and translational medicine, the collection seeks to clarify how synaptopathy arises, establish which measures can detect it in humans, and highlight the therapeutic strategies most likely to preserve or restore auditory nerve function. The broader goal is to move the field toward earlier detection and intervention, before the condition progresses or compounds other forms of hearing loss.ScopeThis Research Topic welcomes original research, reviews, mini reviews, methods, hypothesis and theory, brief research reports, perspectives, and opinion articles. The following is a non-exhaustive list of subjects to be covered:- Mechanisms of cochlear synaptopathy following noise exposure, aging, and ototoxicity- Cellular and molecular pathways of synaptic loss, degeneration, and repair at the inner hair cell to auditory nerve junction- Relationship between synaptopathy and difficulty understanding speech in noise- Development and validation of clinical and electrophysiological tests to detect hidden hearing loss (for example the auditory brainstem response, envelope following responses, middle ear muscle reflex, and speech-in-noise measures)- Biomarkers and objective measures for early identification and monitoring- Animal models and their translation to human diagnosis and treatment- Therapeutic approaches to protect or regenerate synapses, including neurotrophin-based and pharmacological strategies- Prevention strategies and risk factors across the lifespan- Case studies and cohort studies linking suspected synaptopathy to functional hearing outcomes Topic editors: Sasan Dabiri, Brian Richard Earl, Csaba Harasztosi, Joseph Pinkl Source: https://www.frontiersin.org/research-topics/85489/cochlear-synaptopathy-and-hidden-hearing-loss-mechanisms-diagnosis-and-therapeutic-directions