Pupillometry as an Objective Measure of Auditory Perception and Listening Effort Across the Lifespan: A Review

Background/Objectives: This narrative review aims to evaluate the use of pupillometry as an objective measure of auditory perception and listening effort across the lifespan. Specifically, it synthesizes research examining pupillary responses in individuals with and without hearing impairment across pediatric, adult, and older adult populations. The review addresses methodological practices and clinical implications for integrating pupillometry into routine audiological assessment. Methods: 12 peer-reviewed studies published between 2010 and 2025 were selected through a systematic search of databases including PubMed, Scopus, Web of Science, and Google Scholar. Inclusion criteria required empirical use of pupillometry in auditory tasks involving human participants with normal hearing or hearing impairment. Studies were analyzed for population characteristics, experimental paradigms, pupillometric metrics (e.g., peak pupil dilation), level of evidence, and relevance to clinical audiology. This article uses a narrative review approach to organize and interpret findings. Results: Across age groups and hearing conditions, pupillometry consistently demonstrated sensitivity to cognitive load and listening effort, particularly in noisy environments or during complex auditory tasks. Pediatric studies revealed its potential as a non-invasive tool for preverbal children. Adult and older adult studies confirmed that pupillary responses reflect device performance (e.g., hearing aids, cochlear implants) and cognitive–linguistic demands. Methodological variability and individual differences in pupil response patterns were noted as limitations. Conclusions: The findings support the use of pupillometry as a valuable adjunct to behavioral audiometry, offering objective insight into auditory–cognitive load. Its application holds promise for pediatric diagnostics, hearing technology evaluation, and geriatric audiology. Standardization of measurement protocols and development of normative data are necessary to enhance clinical applicability and generalizability.