# Effects of aging on signal in noise processing

> **NIH NIH R56** · UNIVERSITY OF CALIFORNIA AT DAVIS · 2020 · $569,538

## Abstract

PROJECT SUMMARY/ABSTRACT
Age-related hearing loss is a ubiquitous problem, estimated to affect up to one third of the population. This
condition is much more detrimental than `hard of hearing', rather, it has been implicated in a host of co-
morbidities such as cognitive deficits, including dementia and Alzheimer's Disease. It remains unclear if
this is a cause and effect situation or an epiphenomenon. If the former, simple interventions may well lead
to much better mental health among the elderly. The long-term goal of the proposed research program is
to identify the neural coding principles that allow listeners to make sense of, and focus on, particular
sounds (i.e. what you are listening to) when they occur mixed with other sounds (i.e. the background),
something that is common in many listening situations. Although this is an extremely difficult
computational problem, people with normal hearing solve it effortlessly. Unfortunately, this remarkable
ability almost always declines with age, leaving individuals struggling to understand speech in noisy
environments. In order to develop assistive technologies or therapies to restore this critical function, we
need to understand how the brain processes sounds in complex acoustic scenes, and, in particular, exactly
how it fails to do so in aged individuals. Age-related shifts in the coding strategy employed at different
stages of the auditory pathway are believed to involve compensatory changes related to attenuated input
from more peripheral stages, and recent research in older animals has demonstrated quantitative and
qualitative changes in central neural representation of complex sounds. Crucially, these changes appear to
involve changes in how information is transformed along the cortical hierarchy. For this reason, a rigorous
study of the effects of age-related hearing loss must include a comparison of cortical areas, such as core
versus belt, that function at different levels of the processing hierarchy in normal hearing. Moreover, these
central changes impact not only `bottom-up' sound processing along the ascending auditory pathway, but
also `top-down' modulation by attention. The proposed studies will therefore contrast how complex sounds
in challenging listening environments are processed in young versus old animals while those animals are
performing perceptual tasks that either do or do not require auditory attention. These studies will be the
first to track changes in how multiple complex sounds are encoded across hierarchical levels of processing
in the auditory pathway in a primate model of aging, while allowing direct comparisons between
cortical response changes and auditory perceptual deficits.

## Key facts

- **NIH application ID:** 10228422
- **Project number:** 1R56AG067791-01
- **Recipient organization:** UNIVERSITY OF CALIFORNIA AT DAVIS
- **Principal Investigator:** Brian J. Malone
- **Activity code:** R56 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $569,538
- **Award type:** 1
- **Project period:** 2020-09-30 → 2021-01-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10228422

## Citation

> US National Institutes of Health, RePORTER application 10228422, Effects of aging on signal in noise processing (1R56AG067791-01). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10228422. Licensed CC0.

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