10.3 Human Movement and the Brain

The brain is made up of these four key components – cerebrum, brain stem, cerebellum and spinal cord.

The Cerebrum

The cerebrum is the largest part of the brain and is responsible for higher-order functions such as cognition, sensory processing, memory, and motor function, to highlight a few. The cerebrum can be further subdivided into four lobes, each with a wide array of functions.

The Frontal Lobe

Of these four lobes, human movement is initiated within the frontal lobe in a region called the primary motor cortex. For the body to ultimately produce voluntary movement, electrical signals need to be sent from the primary motor cortex to the skeletal muscle fibres by travelling down the following pathway:

1. The primary motor cortex initiates a signal or command that will eventually elicit movement.
2. This command then moves down through the brain and into the spinal cord.
3. The signal continues to descend through the spinal cord towards its destination.
4. Nerves then transmit this signal to the muscle fibres, instructing them to contract or relax.
5. The culmination of these sequential contractions ultimately produces movement.

“What is Neuroscience?” from Principles of Biology by Catherine Creech is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.