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Acquired brain injury

How common is ABI?

According to the Australian Institute of Health and Welfare, more than 1 in 12 Queenslanders are affected by acquired brain injury (ABI) — a disorder which causes damage to the brain, changing the way a person acts, thinks, communicates and behaves. Some forms of ABI may cause long-term intellectual and/or physical disability. It is often called the ‘silent epidemic’ as many of the changes are unseen to the eye.

People with ABI have lower employment outcomes than people with a disability and the population in general. They are also overrepresented in the criminal justice system. Brain Injury Australia estimates that as many as 80% of offenders may have ABI.

There are a number of causes of ABI. These include:

  • trauma to the head caused by a blow incurred in a fall, in a vehicle, bicycle or sporting accident, or from being severely shaken
  • stroke, resulting from a blood clot in the brain or bleeding to the brain
  • hypoxia, which occurs when the brain does not get enough oxygen as a result of an event such as near-drowning, suffocation, electrocution or heart failure
  • tumours growing in the brain
  • infections which attack the brain, such as meningitis and encephalitis
  • maternal drug or alcohol use during pregnancy
  • poisoning, such as lead poisoning.

Brain injuries can vary and the effects of an ABI will depend on the severity of the injury and the part of the brain affected. A person’s age at the time of injury can also have an impact on future development. Brain Injury Australia estimates that 3 out of every 4 people with ABI are men and as many as 2 out of every 3 people are likely to have acquired their brain injury before reaching 25 years of age.

Early signs of ABI

The effects of ABI vary from person to person and some may become more obvious over time.

Often family members, friends and/or colleagues will notice changes in a person, including:

  • memory lapses
  • poor concentration or unable to complete tasks
  • difficulty with making judgements or working things out
  • balance and movement problems
  • comprehension issues and altered thinking ability
  • personality changes including mood swings, depression and anxiety
  • health decline, including the onset of epilepsy or significant changes to weight or growth rates.

Some people who acquire a brain injury will recover fully over time while others will have long term effects.

Types of ABI

ABIs can be divided into two types:

Traumatic brain injury

A traumatic brain injury is caused by a blow to the head, or the head being moved rapidly. This is usually accompanied by some loss of consciousness. When a traumatic brain injury occurs, the brain tissue can become damaged. This damage may be short-term and repair itself quickly or it may take longer to repair or there may be some permanent damage or disability.

Non-traumatic brain injury

A non-traumatic brain injury refers to situations where brain cells are damaged or killed because of exposure to toxic substances, lack of oxygen supply to the brain, brain infection, brain tumour or stroke.


As many ABIs come from trauma to the head suffered in a fall or accident, some people may get an early diagnosis while hospitalised. For others the effects of ABI will become more obvious over time.

Getting assessed and diagnosed with an ABI will give a person access to a range of support, treatments and therapies, including early intervention services. Diagnosis will also help people better understand changes in their functioning, including memory and learning abilities, balance and movement, behaviour, and health in general.

In Queensland, your doctor will assist in getting a diagnosis of ABI. This may involve referral to other specialists such as neurologists, physiotherapists, occupational specialists, psychologists and speech pathologists. They play a role in the diagnosis and assessment of a person with ABI. These professionals will also assist in planning sensory, physical and cognitive rehabilitation.

ABI can be difficult to cope with, and it can take some time for families, friends and carers to adjust to what the person is going through. It is important to recognise that extra support may be needed. It is good to talk to a doctor and find out about the types of support and services available, such as local support groups and professional help such as a counsellor or social worker.

Helpful information

Available support service

Queensland Health provides Acquired Brain Injury Outreach Services (ABIOS). ABIOS offer direct client services and training programs, and runs research projects. ABIOS also offers assistance with behaviour management for people with ABI, their families and carers, and employees in the disability sector, including:

  • professional consultations and advice
  • practical resources
  • intervention and support services, including counselling, education and anger management training
  • skill development and education.

Brain Injury Australia offers support to all Australians with ABI and their families. Organisations including Open Minds, the Developing Foundation and Headway Gold Coast also provide assistance to Queenslanders with ABI.

How is ABI different to intellectual disability and mental illness?

ABI is a spectrum disorder, meaning that people may be affected by several different conditions at the same time. Unlike with intellectual disability, ABI is not dependent on intellectual ability, and intellectual abilities are often not affected at all. A person with ABI may still find it hard to communicate, control or coordinate their thoughts and actions.

The symptoms of ABI and mental illness can be similar. A person with a mental illness is twice as likely to sustain an ABI, and a person with ABI is twice as likely to develop a mental health issue. Synapse, the peak body for Queenslanders with ABI, has a information about mental illness and ABI.

Creative Commons Attribution 3.0 Australia (CC BY 3.0)
Last updated:
18 April 2016

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