How Does the Brain Work? Regions and Functions
Learn how the cerebral cortex, cerebellum and medulla work, how neurones carry information, and which GCSE Biology exam mistakes students should avoid.
The brain works by receiving electrical impulses from receptors, processing the information and coordinating suitable responses. Different regions of the brain carry out different functions.
The main regions and their functions
Cerebral cortex
The cerebral cortex is the outer layer of the brain. It is responsible for conscious thought, intelligence, memory and language.
Information from sense organs is processed in different areas of the cerebral cortex. It also controls voluntary actions—actions you consciously decide to perform.
Cerebellum
The cerebellum coordinates muscular movement and helps maintain balance and posture. It ensures that movements are smooth and controlled.
For example, when you catch a ball, the cerebellum coordinates the timing and movement of the muscles in your arms and hands.
Medulla
The medulla controls unconscious activities that happen automatically, including breathing rate and heart rate. These processes continue without you having to think about them.
How the brain produces a response
Receptors detect a stimulus, which is a change in the environment. Electrical impulses travel along neurones to the central nervous system—the brain and spinal cord. The brain processes the information and sends impulses to an effector, such as a muscle or gland, which produces a response.
A simple pathway is:
stimulus → receptor → coordinator → effector → response
The brain contains billions of interconnected neurones. Connections between these neurones allow different regions to communicate and coordinate complex behaviour.
Common exam mistake
Do not mix up the cerebellum and cerebral cortex. The cerebellum coordinates movement and balance, while the cerebral cortex controls conscious thought, memory and voluntary actions. Also remember that rapid reflex actions do not involve the conscious part of the brain.
Scope: This is AQA GCSE Biology separate-science content, not Combined Science. Higher tier is assumed, although the regions and functions covered here are assessed at both Foundation and Higher tier on Paper 2.
