---
title: "Regional Anatomy of the Central Nervous System"
description: "The brain and spinal cord are organised into regions with distinct cell populations and connections, and the pathways between them run in predictable places. Knowing where a tract runs is what lets a "
canonical: https://lightmysky.com/learn/science/regional-anatomy-of-the-central-nervous-system-mt_S9f5cUS8NZ
source: https://lightmysky.com/learn/science/regional-anatomy-of-the-central-nervous-system-mt_S9f5cUS8NZ.md
retrieved: 2026-09-12
---

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# Regional Anatomy of the Central Nervous System

The brain and spinal cord are organised into regions with distinct cell populations and connections, and the pathways between them run in predictable places. Knowing where a tract runs is what lets a clinician infer the site of damage from the pattern of loss.

Subject: Science · Area: The Human Body · Ages 19 to 20
Page: https://lightmysky.com/learn/science/regional-anatomy-of-the-central-nervous-system-mt_S9f5cUS8NZ

## Ready when they can

- Name the major divisions of the brain and spinal cord and state what each contains
- Trace one ascending and one descending pathway, including where each crosses the midline
- Infer the likely site of a lesion from a described pattern of lost function

## Lesson: Mapping the control centre

The brain divides its labour by region. The cerebrum starts thought, sensing, and movement, the thalamus relays messages between cerebrum and body, the brain stem runs breathing and heart rate, and the cerebellum fine tunes movement and balance. Deep clusters called basal nuclei help start and smooth motion.

The cord flips the brain layout inside out. Grey matter full of cell bodies forms a butterfly in the centre, while white matter of bundled axons wraps the outside. The dorsal horns handle sensing and the ventral horns drive muscles, so each address has a known job.

Axon bundles run as tracts in fixed lanes: ascending tracts carry feeling up to the brain, and descending tracts carry commands down to muscles. Face and neck signals join through cranial nerves instead of the cord. Each tract crosses the midline at its own known place, so the side of the loss is a clue too. Since every lane has a known address, the pattern of lost feeling or movement points back to the damage site.

**Tip.** Read loss like a map: lost feeling with kept movement blames ascending lanes, lost movement with kept feeling blames descending ones, and the body level sets the height of the fault.

**Recap.** Name each region and lane, then trace the lost signal home to the lesion.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [The Brain: Regions and the Evidence for What They Do](https://lightmysky.com/learn/science/the-brain-regions-and-the-evidence-for-what-they-do-mt_BA_DGCDic8)
- [The Reflex Arc and Synapses](https://lightmysky.com/learn/science/the-reflex-arc-and-synapses-mt_evlgCVxTnK)
- [Neurons & Brain Structure](https://lightmysky.com/learn/science/neurons-and-brain-structure-mt_okUMpHsV-P)

## Opens up

- [The Autonomic Nervous System and Its Two Outflows](https://lightmysky.com/learn/science/the-autonomic-nervous-system-and-its-two-outflows-mt_bnVgu4T4E9)
- [Motor Control: From Intention to Muscle](https://lightmysky.com/learn/science/motor-control-from-intention-to-muscle-mt_hrWOuRtPDl)
- [Transmitter Systems and Two Kinds of Receptor](https://lightmysky.com/learn/science/transmitter-systems-and-two-kinds-of-receptor-mt_yXaSbrBxua)