Auditory brainstem response in the identification of cochlear synaptopathy in aged rodents: a systematic review with meta-analysis.

Maria Gabriela Paz da Silva; B&#xe1;rbara Cristiane Sordi Silva; Lilian Cassia Bornia Jacob; K&#xe1;tia de Freitas Alvarenga; Eliene Silva Ara&#xfa;jo

doi:10.1016/j.neuroscience.2026.07.042

PubMed · 42520917

Auditory brainstem response in the identification of cochlear synaptopathy in aged rodents: a systematic review with meta-analysis.

Maria Gabriela Paz da Silva·Bárbara Cristiane Sordi Silva·Lilian Cassia Bornia Jacob·Kátia de Freitas Alvarenga·Eliene Silva Araújo

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Abstract

PURPOSE: This systematic review and meta-analysis evaluated the diagnostic performance of auditory brainstem response (ABR) for identifying age-related cochlear synaptopathies in rodents. METHOD: Following PRISMA guidelines, searches were conducted in PubMed/MEDLINE, Cochrane Library, Scopus, Embase, Web of Science, SciELO, LILACS, and gray literature. Studies evaluating CS in naturally aged rodents using short-latency auditory evoked potentials (AEPs) were included. Study selection, data extraction, risk-of-bias (JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies), and certainty of the evidence (GRADE® system) assessment were conducted independently by two reviewers. Meta-analyses were performed using a random-effects model, with standardized mean differences and 95% confidence intervals. ABR wave I amplitudes were analyzed for click (80 and 90 dB SPL) and tone-burst stimuli stratified by frequency. RESULTS: Among 3,008 identified records, 12 studies were included in the review and five in the meta-analysis. All included studies used ABR measures to investigate CS, with wave I amplitude being the most frequently evaluated biomarker. Meta-analysis demonstrated a significant reduction in ABR wave I amplitude in aged rodents compared with young controls for both click- and tone-burst-evoked responses. Tone-burst ABR showed no significant differences among the evaluated frequencies. These findings should be interpreted with caution due to the limited number of studies and the methodological heterogeneity, which may have reduced statistical power and comparability. CONCLUSIONS: The evidence supports ABR wave I amplitude as a sensitive electrophysiological marker of age-related CS in rodents. Nevertheless, further studies with standardized protocols are needed to strengthen its diagnostic utility and improve comparability across studies.

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Animals Evoked Potentials, Auditory, Brain Stem Aging Cochlea Rodentia Synapses Auditory Cochlear synaptopathy Electrophysiology Evoked potentials Hearing Rats Journal Article Systematic Review Meta-Analysis Review

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Maria Gabriela Paz da Silva, Bárbara Cristiane Sordi Silva, Lilian Cassia Bornia Jacob, Kátia de Freitas Alvarenga, Eliene Silva Araújo. 2026-07-28. Auditory brainstem response in the identification of cochlear synaptopathy in aged rodents: a systematic review with meta-analysis.. https://doi.org/10.1016/j.neuroscience.2026.07.042

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