# Superior Colliculus Interactions with the Parabigeminal Nucleus

> **NIH NIH F31** · UNIVERSITY OF LOUISVILLE · 2021 · $32,639

## Abstract

PROJECT SUMMARY/ABSTRACT
Recent studies have implicated the superior colliculus (SC) and parabigeminal nucleus (PBG) as important
structures involved in the selection and activation of visually-evoked defensive behaviors, such as freeze and
escape. However, the precise role that the SC and PBG play in the initiation of visually-evoked behavior is
unknown, in part due to a gap in knowledge of the synaptic circuits that link the SC and PBG, and the manner in
which the PBG receives visual signals. The proposed project will address this gap by completing a detailed
examination of circuits that link the SC to the PBG. Aim 1 experiments will define the morphology and laminar
distribution of SC cells that contain glutamic acid decarboxylase (GAD) or parvalbumin (PV) and send projections
to the PBG. Aim 2 experiments will test whether these two cells types receive direct or indirect input from the
retina and/or primary visual cortex. Aim 3 experiments will define the synaptic properties of SC-PBG connections.
To investigate these circuits, the proposed experiments use novel combinations of viral vector injections in
transgenic mice, immunohistochemistry, in vitro whole cell recordings from identified cell types, and optogenetic
activation of cell-type specific synaptic terminals. This combination of approaches will address fundamental
questions regarding the circuity of the SC and PBG while providing the applicant with broad-based training in
neuroscience.

## Key facts

- **NIH application ID:** 10132725
- **Project number:** 5F31EY030746-02
- **Recipient organization:** UNIVERSITY OF LOUISVILLE
- **Principal Investigator:** Kyle L Whyland
- **Activity code:** F31 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $32,639
- **Award type:** 5
- **Project period:** 2020-04-01 → 2022-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10132725

## Citation

> US National Institutes of Health, RePORTER application 10132725, Superior Colliculus Interactions with the Parabigeminal Nucleus (5F31EY030746-02). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10132725. Licensed CC0.

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