Your central nervous system (CNS) is made up of your brain and your spinal cord, and is one of two parts of your nervous system.
The other part is your peripheral nervous system, which consists of nerves that connect your brain and spinal cord to the rest of your body.
Your brain controls most of the functions of your body, including awareness, movement, what you think and say, and what you see, hear, feel, taste and smell.
Your spinal cord is an extension of your brain. It carries messages to and from your brain via the peripheral nerves connected to it.
Nerves also connect your spinal cord to a part of your brain called the brainstem.
Your brain and spinal cord are protected from damage by a clear liquid called cerebrospinal fluid.
Read more about your nervous system.
The most important parts of your brain are the cerebrum, the cerebellum, the thalamus, the hypothalamus and the brainstem.
The cerebrum is the largest part of your brain. It controls voluntary actions, speech, senses, thought and memory. It is divided into left and right hemispheres, linked by a hard body in the centre of the brain which is dense in neurones called the corpus callosum.
Each hemisphere is divided into four lobes, or sections, which are all connected.
- Your frontal lobes control movement, speech and some of the functions of the mind like behaviour, mood, memory and how to organise yourself and others.
- Your temporal lobes play an important part in memory, hearing, speech and language.
- Your parietal lobes play an important part in taste, touch, temperature and pain, and also in your understanding of numbers, your awareness of your body and your feeling of space.
- Your occipital lobes are vital for being able to see clearly.
Deep inside the brain are the thalamus and the hypothalamus. The thalamus moves information to and from the lobes, and controls movements and memory. The hypothalamus controls appetite, thirst and body temperature, and produces hormones that control the release of other hormones in the pituitary gland.
At the base of the brain is the brainstem. It is important for breathing, blood pressure and how your body reacts to danger.
Last reviewed: July 2017