How Alcohol Affects Your Brain When You're Drunk

Booze has a lot to answer for.

Ever wondered why you become an almighty extrovert when you’ve had a couple of drinks?

According to Youtube channel SciShow, it’s because the toxin ethanol enters your brain and causes all kinds of havoc, affecting your brain cells and the way they interact with one another.

The video explains that the human body sees alcohol as a poison and, as a result, it tries to get rid of it immediately.

“Whatever your body can’t process right away can end up in your brain, which affects how your cells interact with each other and causes all those things that we associate with drunkenness,” says the narrator.

When you drink alcohol, the ethanol is absorbed into your blood stream through your stomach lining or small intestine. Your liver is responsible for filtering out this ethanol and breaking it down, so your body can safely get rid of it.

Firstly, it’s converted into acetaldehyde, which is toxic. Then, another enzyme turns acetaldehyde into acetate, which is harmless and eventually passed through your urine.

Your liver does its best to filter out the ethanol in your body, but if you keep drinking, it might not be able to keep up. As such, the ethanol circulates in your blood stream and eventually reaches your brain.

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Usually toxins are kept out of your brain thanks to something called the “blood-brain barrier”, which is essentially a filter made up of specialised cells and proteins.

However ethanol can easily get past this barrier as it’s attracted to fats, so it can pass through those fatty cell membranes.

Once it’s in your brain, it begins to alter the signalling between your brain cells.

The brain uses chemicals called neurotransmitters to send messages between cells. The two most important ones are GABA - which causes neurons to send fewer signals and is an inhibitory neurotransmitter - and glutamate - which causes neurons to send more signals and is an excitatory neurotransmitter.

Ethanol, being the friendly little toxin that it is, binds to both of these receptors and changes the messages the neurons receive.

Typically, GABA signals are enhanced, while glutamate signals are weakened - resulting in slower brain activity overall. This is why it’s known as a depressant.

Alcohol also reduces activity in the cerebellum, which is responsible for motor function, meaning you stumble around more and it suppresses areas of the brain responsible for self control and social inhibition.

This makes people more emotional, sociable and prone to risky decisions.