What is ABI?

Learn more about acquired brain injury, also known as ABI.

What is acquired brain injury?

As a general overview, acquired brain injury, or ABI, refers to any injury or damage to the brain that occurs after birth.

This injury or damage can greatly - and permanently - affect the way a person thinks, feels and behaves.

The outcomes and effects of ABI are different for each person and often depend on the cause, nature and severity of the injury. Some effects of brain injury are only experienced in the short term, but many permanently impact on the person’s ability to lead an independent life.

brain and cogs working

Definition of Brain Injury

‘Acquired brain injury (ABI) is injury to the brain which results in deterioration in cognitive, physical, emotional or independent functioning. ABI can occur as a result of trauma, hypoxia [where a person has less than the normal level of oxygen in the body], infection, tumour, substance abuse, degenerative neurological diseases or stroke. These impairments to cognitive abilities or physical functioning may be either temporary or permanent and cause partial or total disability or psychosocial maladjustment.’
(National Policy on Services for People with Acquired Brain Injury, 1994).

What causes a brain injury?

Some of the common causes of brain injury include;

  • A motor vehicle crash;

  • Concussion or a sporting accident; 

  • Stroke; and

  • Assaults.

The brain can also be injury from other causes such as alcohol and drug abuse, near drowning or infection and disease. For further information on the causes of ABI, visit the link below.

Did you know?

The effects of brain injury are difficult to predict - and will be different for each person. Whatever the nature of the eventual disability - the lives of people with ABI change, along with the lives of those close to them.

Causes of brain injury >

Why brain injury occurs?

Brain injury occurs because when the head is struck forcefully, for example as the result of a car crash, and the brain slams against the inside of the skull. 

This movement of the brain inside the skull, known as contrcoup,  can cause physical injuries to the brain like swelling, bleeding, twisting - and even tearing of tissue; resulting in often permanent and irreversible damage.

What are the effects and impacts of acquired brain injury?

People with ABI often experience difficulties with:

  • Communicating;

  • Thinking;

  • Physical functioning; and

  • Controlling their emotions and behaviour.

Memory can also be affected, as well as the ability to concentrate, plan and solve problems. Find further information about the effects of brain through the link below.

Effects of brain injury >

An invisible disability

Brain injury is sometimes called the ‘invisible’ (or hidden) disability because its effects are not easy to see or they are not recognised as brain injury.

A person with brain injury may outwardly appear to be unaffected.

Long term effects of brain injury are usually in the areas of thinking and behaviour and are not as easy to see and recognise as many physical disabilities.

Brain injury is often undiagnosed.

As a result of these issues, the difficulties faced by people with brain injury are frequently misunderstood or ignored.

What is "cognition?"

Cognition is the "conscious process of the mind by which we are aware of thought and perception, including all aspects of perceiving, thinking and remembering" (ABI The Facts, Synapse, 2013). In basic terms, it is the way our brain works behind the scenes, how we learn and how we perceive the world around us - although it is a very complex topic.


Brain injury can be classified as mild, moderate or severe. 
Brain injury can result in mild concussion, coma or death.

Mild brain injury doesnt necessarily mean minor

Brain injury can be classified as mild, moderate or severe. 
Brain injury can result in mild concussion, coma or death.

Brain injury in Australia

Research indicates that one in 45 Australians have an ABI which has resulted in significant limitations for people’s capacity to lead independent lives.

The prevalence rates are higher for males than females and increase with age. Two thirds of the ABI population sustained their injury under the age of 25 years old. With a normal life expectancy this can lead to decades of consequences.

Brain injury in Tasmania

In Tasmania it is estimated that each year 2,500 people acquire a brain injury.

It is estimated by the Tasmanian Government that the cost of an 18 year old male with ABI (as a result of car crash) will be $12 million in care, support and medical fees over the person’s lifetime.

Where can I learn more about brain injury?

The Brain Injury Association of Tasmania exists to assist people with brain injury, their families, carers and service providers within the community to understand and manage the impact of brain injury.

You can contact BIAT today via our freecall phone number 1300 242 827, or find further contact details on our contact page via the button below.

Contact BIAT >
  • Acquired Brain Injury - The Facts

    Acquired Brain Injury: The Facts is a practical guide to understanding and responding to Acquired Brain Injury and behaviours that challenge our understanding.

    View link to publication >