# Cross-modal enhancement of auditory plasticity and performance in adults

> **NIH NIH R01** · JOHNS HOPKINS UNIVERSITY · 2020 · $491,654

## Abstract

Project Summary
 It is well documented that the ability of the brain to undergo plasticity becomes limited in adults. In
particular, sensory experience-dependent plasticity of cortical circuits is rather confined to a limited time during
development, termed the critical period. Recovery and refinement of sensory processing is therefore difficult in
adults. For example, the success rate of speech recognition in artificial cochlear implant patients becomes
quite low, if the surgery is done later in life. Hence discovery of mechanisms that can recover adult cortical
plasticity is of essence to benefit recovery of hearing or for treating abnormal auditory processing as occurs
with tinnitus. We found that temporary visual deprivation is quite effective at producing large-scale plasticity in
the adult primary auditory cortex (A1) of mice. Such changes occurred as potentiation of feedforward excitatory
synapses from the primary auditory thalamus (MGBv) to layer 4 (L4) as well as L4 to L2/3. This was
accompanied by weakening of synapses arising from lateral intracortical sources to L2/3 of A1. In parallel, we
also observed refinement of cortical circuits of A1 L4 and L2/3. Collectively, these changes suggest that A1
circuit adapts to allow better processing of bottom-up auditory inputs, which is consistent with our published
observation of refinement of A1 L4 neuronal receptive field and lowering of detection threshold in visually
deprived mice. In this application, we aim to determine the mechanisms involved in driving adult A1 plasticity
with visual deprivation, and whether visual deprivation improves auditory behavior in adults. Based on our
observation that visual deprivation induced potentiation of thalamocortical (TC) inputs to A1 L4 requires
audition, but no due to changes in the auditory environment, we surmise that there is central adaptation in
circuits mediating auditory signals going through the thalamus and the cortex. In particular, we hypothesize
that short-term visual deprivation promotes A1 plasticity in adults by regulating inhibitory circuits at the level of
thalamus and cortex (Aim 1). The circuit and synaptic adaptation seen in A1 following vision loss accompanied
refinement of A1 L4 neural function, and is predicted to enhance auditory function. We will examine how short-
term visual deprivation alters auditory behavioral tasks in adults, and investigate whether this is due to
changes in A1 neuronal responses and population encoding during auditory tasks using in vivo 2-photon
imaging (Aim 2). Results from our proposed study will provide mechanistic understanding on how short-term
visual deprivation enables plasticity of adult A1 via regulation of thalamic and cortical circuits, and will provide
means to enhance auditory processing in the adult brain that could benefit development of treatment options
for enhancing or recovering auditory function as would be needed for better prognosis of artificial cochlear
implants. Furthermore, o...

## Key facts

- **NIH application ID:** 10028097
- **Project number:** 1R01DC018790-01
- **Recipient organization:** JOHNS HOPKINS UNIVERSITY
- **Principal Investigator:** PATRICK O KANOLD
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $491,654
- **Award type:** 1
- **Project period:** 2020-07-01 → 2025-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10028097

## Citation

> US National Institutes of Health, RePORTER application 10028097, Cross-modal enhancement of auditory plasticity and performance in adults (1R01DC018790-01). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10028097. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*