# Functional consequences of heterotypic retinal ganglion cell coupling

> **NIH NIH R01** · NORTHWESTERN UNIVERSITY · 2020 · $355,500

## Abstract

Neurons communicate using both chemical transmission at traditional synapses and electrical transmission
through gap junctions. Electrical transmission is well studied in the mammalian retina, where gap junctions
exist between all five major classes of neurons. Retinal ganglion cells (RGCs), the output cells of the retina,
comprise ~40 functional types in mammals. Gap junctional coupling among RGCs has always been described
as “homotypic,” that is, between RGCs of the same type. We have discovered, for the first time, heterotypic
electrical coupling in the mouse retina, between two RGCs of different types, called F-miniON and F-miniOFF
RGCs.
The existence of heterotypic RGC coupling breaks the rule of functional parallelism between RGC channels
and requires new ideas about the role of coupling in retinal computation. This project aims to explore the
functional role of heterotypic RGC coupling in the F-mini network through two specific aims. In Aim 1 we will
determine whether coupling between F-miniON and F-miniOFF RGCs creates a novel pathway for mixing ON and
OFF signals in the inner retina. In Aim 2 we will determine which features of moving stimuli are encoded by
synchronized spiking between F-miniON and F-miniOFF RGCs.
The proposed studies will advance our understanding of how chemical and electrical synaptic inputs interact to
perform neural computations and how sharing of signals between parallel pathways contributes to sensory
encoding.

## Key facts

- **NIH application ID:** 9944076
- **Project number:** 1R01EY031329-01
- **Recipient organization:** NORTHWESTERN UNIVERSITY
- **Principal Investigator:** Gregory William Schwartz
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $355,500
- **Award type:** 1
- **Project period:** 2020-07-01 → 2025-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9944076

## Citation

> US National Institutes of Health, RePORTER application 9944076, Functional consequences of heterotypic retinal ganglion cell coupling (1R01EY031329-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9944076. Licensed CC0.

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