# The organization of cerebello-thalamo-cortical circuit in the motor system

> **NIH NIH R21** · UNIVERSITY OF TEXAS AT AUSTIN · 2024 · $231,257

## Abstract

PROJECT SUMMARY/ABSTRACT
Precise control of voluntary movement is crucial for almost all behaviors and the quality of life. While many
brain regions are involved in the process, the interaction between the cerebral cortex and the cerebellum is
particularly essential. When the cerebellum communicates with the cerebral cortex, it sends signals to the
thalamus, which relays the information to the cerebral cortex. This cerebello-thalamo-cortical circuit has been
studied extensively because of its functional significance. However, the current understanding of the circuit is
based mainly on anatomical connection and the assumption that neurons within each brain region behave
similarly. Molecular and physiological heterogeneity within the neuronal population is barely considered, posing
a challenge in understanding how the circuit allows coordinated movements of the entire body. First, although
the cerebellum projects axons to various thalamic subregions, the strength of synaptic transmission
substantially varies. Therefore, the anatomical connection does not accurately represent the functional
organization of the circuit. Second, many recent studies showed that a neuronal population, traditionally
considered a single group, can be divided into several subtypes based on their distinct gene expression
profiles. These molecularly defined neuronal subtypes often show different physiological properties and
anatomical connectivity, engaged in distinct functional circuits. Recently, we studied the functional properties of
the ventrolateral thalamus (VL), one of the thalamic subregions and the primary target of the cerebellum. While
the VL is traditionally considered a homogenous neuronal population, our preliminary data showed substantial
variation in their excitability and synaptic properties, which might reflect previously unrecognized connectivity
between the cerebellum and the VL. Furthermore, a recent study showed that VL neurons consist of several
subtypes exhibiting distinct patterns of gene expression. These data suggest that the functional organization of
the cerebello-thalamo-cortical circuit is finer and more sophisticated than previously thought. In the proposed
research, we will perform whole-cell patch-clamp recordings and circuit tracing with the transgenic mice that
label the molecularly defined VL neuron subtypes. We will study their projection patterns to the cerebral cortex
and their contribution to the functional heterogeneity in the VL (Aim 1). We will also examine their presynaptic
origin in the cerebellar nuclei and the extent to which the cerebellar nuclei contribute to the functional
heterogeneity in the VL (Aim 2). Successful completion of this project is expected to provide novel insight into
the organization of the motor circuit.

## Key facts

- **NIH application ID:** 10870677
- **Project number:** 1R21NS137118-01
- **Recipient organization:** UNIVERSITY OF TEXAS AT AUSTIN
- **Principal Investigator:** Hiroshi Nishiyama
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $231,257
- **Award type:** 1
- **Project period:** 2024-04-01 → 2026-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10870677

## Citation

> US National Institutes of Health, RePORTER application 10870677, The organization of cerebello-thalamo-cortical circuit in the motor system (1R21NS137118-01). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10870677. Licensed CC0.

---

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