Synapse - reconnecting lives

The brain controls and coordinates everything we do: movements, feelings, thoughts, breathing and bodily functions.

 The brain is made up of billions of nerve cells that communicate through electrical and chemical activity. It  weighs around 1.3 kg and is cushioned with the skull by cerebrospinal fluid which circulates around the brain through a series of cavities called ventricles.

The brain makes up only two percent of the body's weight but uses 20% of the oxygen supply and blood flow. Brain cells are quite fragile and need protection from trauma, pressure, infection, poisoning or lack of oxygen. They begin to die if they do not receive oxygen after three to five minutes.

The brain is divided into a number of parts, which have specific functions and are designed to work together. 

Hemispheres & lobes of the brain

The largest part of the brain is divided into two halves, with the left half controlling the right side of the body and the right half controlling the left side of the body.

These hemispheres will be more dominant for certain activities. For example,  the left hemisphere is mainly involved with speech, language, reading and writing, while the right hemisphere is usually more focused on visual perception, and interpreting nonverbal information. Each hemisphere is divided into four lobes.

Frontal lobes are involved in problem-solving, planning, making judgments, abstract thinking and regulating how we act upon our emotions and impulses. Marked changes in a person's personality and social skills can occur from damage to this area.

Temporal lobes are involved in receiving and processing what we hear, visually recognizing objects, memory and learning. The temporal lobes are also involved in personality, emotions and sexual behaviour.

Parietal lobes are involved in monitoring sensation and body position, understanding time, recognizing objects, reading and judging the position of objects in the environment.

Occipital lobes receive and interpret information from our senses including colour, size, shape and distance.

The cerebellum

The cerebellum is located at the back and below the main hemispheres of the brain. It controls balance and the muscle coordination needed for large body movements. It lets a person know how fast, how hard, how far and in what direction his or her body parts are moving.

The brain stem

The brain stem connects the brain to the spinal cord and regulates basic activities such as wakefulness, breathing, swallowing, eye movement, body temperature and heart activity. 

Brain injury

This brief introduction to the brain reveals not only why the brain is so vulnerable to injury, but also why the effects of a brain injury can be so varied. Each part of the brain deals with different aspects of what we think, feel and do so injury to specific areas causes many different problems to arise. 

The brain can be injured as a result of many things including: a car accident, stroke, alcohol or drug abuse, tumours, poisoning, infection, disease, near drowning, hemorrhage, AIDS, and disorders such as Parkinson's disease, multiple sclerosis, and Alzheimer's disease.

 The good news is that the brain does have a limited ability to heal itself and there are many rehabilitation strategies to compensate for lost skills and abilities. See our complete range of fact sheets for practical support.