Acquired brain injury refers to any brain damage that happens after birth. Alcohol is one of the many causes of acquired brain injury. The injury inflicted by alcohol abuse is referred to as alcohol related brain injury (ARBI). More than 2,500 Australians are treated for ARBI every year. Just how much damage is done depends on a number of factors. These include individual differences, as well as the person's age, gender, nutrition and their overall pattern of alcohol consumption.

A person with ARBI might experience problems with memory, cognitive abilities and physical coordination. A younger person has a better chance of recovery because of their greater powers of recuperation. However, the effects of alcohol related brain injury can be permanent for many sufferers.

Alcohol and brain injury

Brain injury can be caused by alcohol because it:

• Has a toxic effect on the central nervous system.
• Results in changes to metabolism, heart functioning and blood supply.
• Interferes with the absorption of vitamin B1 (thiamine), which is an important brain nutrient.
• May be associated with poor nutrition.
• Can cause dehydration, which may lead to wastage of brain cells.
• Can lead to falls and accidents that injure the brain.

Alcohol consumption and ARBI

Alcohol is one of the most popular drugs in Australia, with around half of the population over 14 years of age drinking at least once a week . Alcohol consumption ranges from light (social drinkers) to heavy consumption. Decline in cognitive functioning is gradual, and depends upon the amount of alcohol consumed and for how long.

Alcohol related brain injury is more likely to occur if a person drinks heavily on a regular basis over many years. It is possible to develop ARBI over a short period of time, if the drinking is aggressive enough. This can be known as 'binge drinking', which means drinking more than six drinks at a time. Safe levels of alcohol consumption include:

• For men - a maximum of four standard alcoholic drinks per day with at least two alcohol free days every week.
• For women - a maximum of two standard alcoholic drinks per day with at least two alcohol free days every week.

Disorders associated with ARBI ARBI is associated with changes in cognition (memory and thinking abilities), difficulties with balance and coordination, and a range medical and neurological disorders. Some alcohol related disorders include:

• Cerebellar atrophy - the cerebellum is the part of the brain responsible for muscle coordination. Damage results in difficulties with balance and walking, which is called 'ataxia'.
• Frontal lobe dysfunction - the brain's frontal lobes are involved in abstract thinking and planning. Damage results in cognitive difficulties.
• Hepatic encephalopathy - many people with alcohol related liver disease develop particular psychiatric symptoms, such as mood changes, confusion and hallucinations.
• Korsakoff's amnesic syndrome - a loss of short term memory.
• Peripheral neuropathy - the extremities are affected by numbness, pain, pins and needles.
• Wernicke's encephalopathy - a disorder caused by a severe deficiency of vitamin B1. Some of the symptoms include ataxia, confusion and problems with vision.