The Brain

 

The brain is located in the skull and is the communication and control centre of the body. It receives, processes and evaluates many kinds of input, decides on the response or action that needs to be taken; and then initiates a response.

 

These responses include:

 

• Involuntary activity to maintain homeostasis (balance) in the body e.g. blood pressure, temperature, heart rate, respiratory rate

• Voluntary actions e.g. movement

 

The brain is protected is protected by the skull, three membranes (meninges) and cerebrospinal fluid (CSF)

 

It is divided into two hemispheres; left and right. 

 

Structures of the brain and their functions

 

• The brain stem is made up of the midbrain, pons and medulla oblongata) - This controls involuntary reflex actions e.g. breathing rate, heart rate and swallowing.

 

• The cerebellum - The cerebellum (“little brain”) is a structure that is located at the back of the brain, underneath the occipital and temporal lobes of the cerebral cortex. This controls our sense of balance and lets us make precise and accurate movements. It also maintains our posture.

 

• The diencephalon (includes the thalamus and hypothalamus) - This is the centre part of the brain, that controls homeostatic mechanisms and the autonomic nervous system.

 

• The cerebrum - The left and right cerebral hemispheres form the largest part of the brain. The outer surface of the brain is covered by elevations (gyri), that are separated by grooves (sulci). Each hemisphere is divided into four main areas that control movement, interpret sensory impulses and control thought, memory, emotions and personality traits.