# Neural determinates of cortical plasticity with age and hearing loss

> **NIH NIH R01** · MEDICAL UNIVERSITY OF SOUTH CAROLINA · 2021 · $390,343

## Abstract

PROJECT SUMMARY/ABSTRACT
Age-related hearing loss is one of the most common chronic conditions of aging, yet little is known about how
the brain adapts to this gradual degradation and loss of input and the subsequent reintroduction of audible
sound through amplification. This neural adaptation, or plasticity, occurs in response to a loss of input and
through acoustic experiences. In the proposed research program, in response to RFA-AG-18-017 “Central
Neural Mechanisms of Age-Related Hearing Loss, the experiments in Aim 1 characterize age and hearing loss
effects on homeostatic plasticity, or the degree to which cortical neurons regulate their excitability relative to
incoming neural activity. Experiments are designed to identify how relationships between activity in the
auditory nerve and auditory cortex change with increasing age and hearing loss and by identifying the
underlying neural mechanisms contributing to these changes, specifically changes in the neurochemical
environment. Proposed experiments then test the extent to which these plastic changes effect self-perception
of hearing handicap and speech recognition, and are altered by an individual's acoustic experiences.
Experiments in Aim 2 examine age and hearing loss effects on the capacity for change and adaptation with
experience, or experience-driven plasticity, which can be induced in minutes through exposure to a repetitive
stimulus presented in a specific manner, and is manifested as an enhancement in the brain's response to the
stimulus post-exposure. By examining this type of plasticity across auditory and visual modalities, the
proposed experiments are designed to disambiguate effects attributed to increasing age and those that are
specific to changes in the auditory system. Similar to homeostatic plasticity, we will examine the extent to
which individual differences in experience-driven plasticity arise from differences in the underlying
neurochemical environment. We will integrate results across aims to identify relationships among homeostatic
and experience-driven plasticity, and how increasing age and hearing loss drive these relationships. A
significant advancement in our understanding of the plastic changes that occur with increasing age and
hearing loss is needed so that plastic processes can be utilized to allow maximal benefit during rehabilitation.
Moreover, our ability to assess the contribution of the neurochemical environment to human cortical plasticity
may provide specific targets for intervention to enhance adaption during rehabilitation.

## Key facts

- **NIH application ID:** 10163836
- **Project number:** 5R01DC017619-04
- **Recipient organization:** MEDICAL UNIVERSITY OF SOUTH CAROLINA
- **Principal Investigator:** KELLY C HARRIS
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $390,343
- **Award type:** 5
- **Project period:** 2018-06-05 → 2023-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10163836

## Citation

> US National Institutes of Health, RePORTER application 10163836, Neural determinates of cortical plasticity with age and hearing loss (5R01DC017619-04). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10163836. Licensed CC0.

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