About the Brain
The brain is a soft, delicate, jelly-like organ that is the centre of the human nervous system and is responsible for all of the body’s functions. It weighs approximately 3lbs, or just under 1.5kg, and is enclosed within the skull, floating in a protective sea of cerebrospinal fluid. The fluid supports and nourishes the brain and acts as a sort of shock absorber.
Not only is the brain protected by the cerebrospinal fluid but also by three layers of membrane, known as the dura, pia and arachnoid, that lie between the brain and skull.
The space between the pia and arachnoid membranes is known as the subarachnoid space. The subarachnoid space contains blood vessels that supply and drain the brain.
To function the brain has to have a regular blood supply from the heart, the brain is criss-crossed by a network of large arteries that divide into smaller branches.
The brain can be divided into four areas, known as “lobes”:
- The Frontal Lobes
- The Temporal Lobe
- The Parietal Lobe
- The Occipital Lobe
The different lobes are responsible for different functions and skills, injury to each causes different immediate and long term effects.
Facts & Figures about Brain Injury
- Each year in the UK around 1,000,000 people will attend A&E as a result of a head injury.
- Severity of injury of those admitted;
- 49% of brain injuries are as a result of road traffic accidents
- 20% of child brain injuries are caused by cycling accidents
- More than 120,000 people are suffering long term effects as a result of a brain injury
- Males are 3 times more likely to suffer a brain injury than females, this rises to 5 times between the ages of 16-30
Types of Injury
A head injury is classed as any trauma to the scalp, skull or brain.
These types of head injuries are known as acquired brain injuries (ABI’s) or traumatic brain injuries (TBI’s), these terms are often used interchangeably, and refer to head injuries sustained after birth.
There are three types of brain injury – closed, open and crush.
A closed head injury is the most common type of head injury. This type of injury often occurs as a result of rapid acceleration or deceleration, for example when a car is hit from behind. The head is then rocked backwards and forwards or rotated, the brain follows and this then can result in nerve fibres being twisted, stretched or even torn.
The front of the skull has sharp ridges, if the brain collides with these ridges more damage may be caused, arteries and veins running through the brain can be damaged, allowing blood to leak.
An open, or penetrating, head injury involves being struck by an object that has broken the skull and entered the brain. This can happen when travelling at speed, such as going through the windscreen during a car accident, falling from height, bullet wounds or being struck by an object.
A crush type injury is the least common type of injury and involves the head being caught between two hard objects, such as the wheel of a car and the road.
Injury to the head/brain can be from a traumatic event or as a result of a neurological condition.