# Synaptic Plasticity in Young versus Aged Visual Cortex

> **NIH NIH R01** · UNIVERSITY OF WISCONSIN-MADISON · 2024 · $388,750

## Abstract

Project Summary
The decline in synaptic plasticity with age is thought to impose severe constraints on the recovery from
amblyopia in adults. Although this developmental loss was previously thought to be irreversible, our previous
work established that robust plasticity can be reactivated in the adult visual cortex by dark exposure (DE)
followed by light reintroduction (LRx). We outline a series of experiments to delineate the cellular and
molecular mechanisms that couple DE/LRx to the rejuvenation of synaptic plasticity in the adult visual system.
We propose that DE induces homeostatic changes in the composition of synaptic NMDARs in the primary
visual cortex, which lowers the threshold for Hebbian plasticity. However, the response to DE over-
compensates for the loss of visual input and results in neuronal hyper-excitability. The threshold for activation
of perisynaptic proteolysis by LRx at thalamocortical synapses is also lowered by DE. The response to LRx
reduces feed-forward excitation to the cortex and is mediated by rapid plasticity of presynaptic function.

## Key facts

- **NIH application ID:** 10827052
- **Project number:** 2R01EY016431-15
- **Recipient organization:** UNIVERSITY OF WISCONSIN-MADISON
- **Principal Investigator:** Elizabeth Mary Quinlan
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $388,750
- **Award type:** 2
- **Project period:** 2006-09-01 → 2028-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10827052

## Citation

> US National Institutes of Health, RePORTER application 10827052, Synaptic Plasticity in Young versus Aged Visual Cortex (2R01EY016431-15). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10827052. Licensed CC0.

---

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