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The effects of alcohol and drugs on the brain


Brain Awareness Week, which takes place from 14-20 March, is a worldwide celebration of the brain. With that in mind, we thought it was important to highlight some of the adverse effects of alcohol and drugs on brain health and mental well-being. After all, if we’re to celebrate the brain it’s important to understand how to care for it in the long-term. If you think you’re struggling with addiction, talk to us about alcohol or drug rehab today. 
Difficulty walking, slurred speech, blurred vision and impaired memory are just a few of the immediate effects of alcohol on the brain. Some of these impairments occur after only one or two drinks and then wear off. A persistent, chronic drinker though might experience brain deficits that can linger well after achieving sobriety.

Signs of addiction

The short-term effects of alcohol

Heavy drinking can have considerable and far-reaching effects on the brain. These can range from simple memory lapses, to debilitating permanent conditions that require lifetime medical care. Even moderate drinking can lead to short-term impairment. Alcohol can produce detectable impairments in memory after only a few drinks and, as the amount of alcohol intake increases, so does the degree of impairment.

Large quantities of alcohol, especially when consumed quickly and on an empty stomach, can produce blackouts. In other words, the intoxicated person will experience extended periods where they cannot recall key details of a drinking event, or even a whole evening.

The negative signs of addiction to alcohol

Our brains rely on a delicate balance of chemicals. Alcohol is a depressant, so can disrupt that balance, affecting our thoughts, feelings and actions – and sometimes our long-term mental health. This is partly down to ‘chemicals, known as neurotransmitters’, that help to transmit signals from one nerve (or neuron) to another in our brains.

The more you drink, the more your brain is affected. When high levels of alcohol are involved, instead of pleasurable effects, it’s possible that a negative emotional response can take over and make you angry, aggressive, anxious or depressed. If you drink heavily and regularly you’re also likely to develop some symptoms of depression. That’s a result of brain chemistry once more.

The effects of drugs on the brain

The difference between normal rewards and drug rewards can be the difference between someone whispering in your ear and someone shouting into a microphone. Just as we turn down the volume on a blaring radio, the brain adjusts to dopamine surges by producing less dopamine. As a result, dopamine’s impact on the reward circuit of the brain of someone who abuses drugs can become abnormally low, and that person’s pleasure senses are hindered.

This is why a person who abuses drugs eventually feels flat, lifeless, and depressed. They need to keep taking drugs to bring their dopamine levels back to normal. Of course, this merely acts as a vicious cycle. A frequent user will often need to take larger amounts of drugs to produce the familiar dopamine high. This is known as tolerance.

Tolerance can eventually lead to profound changes in neurons and brain circuits that can compromise the health of the brain. For example, glutamate is another neurotransmitter that influences rewards circuit and the ability to learn. When glutamate levels are altered by drug abuse, the brain tries to compensate for the change, which can negatively impact cognitive function.

Break the habit with Port of Call

Long-term drug abuse can also trigger adaptations in habit. For example, conditioning can cause a person’s daily routine or environment to be associated with their drug experience. This can trigger uncontrollable cravings whenever they are exposed to these prompts. This learned behaviour can linger even long after achieving recovery and long-term abstinence.

If you’re worried about your relationship with alcohol or drugs, speak to Port of Call today for free and confidential advice. If you think you need private rehab, we can discuss all your options with you. We can help you, or your loved one, to access the right addiction support at the right time. Speak to one of our advisers today by calling our free phone line on 08000029010 or text ‘PORT’ to 82228 for a call back.

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