Impact of Alcohol on the Developing Brain

Alcohol affects two crucial parts of the brain which are vulnerable when a teenager is developing. This can result in irreversible brain changes that can impact decision making, personality, memory and learning.

How does alcohol affect messages in the body?

Ever played Chinese whispers? Well your brain does every day, getting messages from your nerve cells to your body. It needs to send the correct messages throughout your body so it functions correctly.

Alcohol acts on the nerve cells of the brain and disrupts the communication between nerves cells and other cells of the body. Alcohol does this by altering the actions of two major neurotransmitters in the brain. [1]

Neurotransmitters are chemical messages, which enable nerve cells to talk to each other and to other cells in the body. Alcohol suppresses the activities of certain nerve pathways, eventually making a person appear sluggish, lethargic and slow-moving. [2]

While research tells us alcohol can damage the developing brain it is not clear how much alcohol it takes to do this. For these reasons, it is recommended that for under 18’s no alcohol is the safest choice and that they delay the initiation of drinking for as long as possible. [3,4]

What parts of the brain are affected?

While there are several parts of the brain affected by alcohol during the teenage years there are two areas of the brain that are particularly sensitive to alcohol during this period.

Hippocampus

The hippocampus is responsible for memory and learning.

Studies of adolescents show that heavy and extended alcohol use is associated with a 10% reduction in the size of the hippocampus. It also shows that the function of the hippocampus is uniquely sensitive to alcohol at this time and that alcohol may be poisonous to the nerve cells of the hippocampus causing them to be damaged or destroyed. [3]

Prefrontal lobe

The prefrontal lobe is important for planning, judgement, decision making, impulse control and language.

This area of the brain changes the most during the teenage years. Research with heavy drinking adolescents’ shows that these young people have smaller prefrontal lobes than young people of the same age who do not drink. [3]

The body of research about the effects of alcohol on the developing brain is still growing. Studies have shown physical changes in the brain and evidence of impaired problem solving and other cognitive function resulting from young people’s alcohol use. [4]

It is well known that of young people who do drink in Australia, the number who experience alcohol-related problems is high. Studies of these young people have shown significant and detrimental changes in brain development compared with their non-alcohol-using peers. [3]

Does alcohol affect the brain in other ways?

Alcohol affects cells in the body, and the most immediate impacts are seen on the brain. [5]  Alcohol is a depressant that affects the brain by causing the brain to slow down. This can result in:

• Slurred speech.
• Poor muscle control and judgement.
• Confusion
• Slower reactions.
• Poor vision.
• Lack of coordination.
• Sleep disruption [3]

The earlier a person starts drinking alcohol (drinking at levels that are likely to cause injury or ill-health), [3] the greater the risk of changing the development of the brain. This can lead to problems with memory and learning, and increases the risk of having alcohol-related problems later in life.

Learn about the other effects of alcohol on young people.

Alcohol and enjoyment

Changes in the wiring of a young and developing brain due to alcohol use can result in finding alcohol more rewarding when they are adults. A strong feeling of reward from alcohol use may be associated with an increased risk of alcohol-related problems when they are adults. [6,7]

What about the future?

Alcohol can affect your child’s brain which continues to develop until their early twenties. Alcohol can negatively impact on a young person’s problem solving skills and performance at school, as well as potentially affecting their body, mood and mental health. [8]