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How does alcohol affect the Nervous System

We’ve all heard the statement that “drugs kill brain cells”, but what about alcohol? Does the same thing apply? Does alcohol kill brain cells, and is that why we shouldn’t go out binging on a ton of alcohol?

First lets talk a little about how the brain functions. It’s estimated that there are over 100 billion brain cells (neurons) in the human brain. These cells are unique in that they can communicate very quickly with each other by sending nerve impulses, also known as action potentials. When the nerve impulse reaches the end of the axon, the axon terminals release neurotransmitters which then relays the signal to the next cell.

Obviously, regulating the release of neurotransmitter is a very crucial and exact process. If something goes wrong in this process, this can lead to some “interesting” effects.

There are many different neurotransmitters, and these different neurotransmitters have different functions. In general, some neurotransmitters stimulate/excite certain functions, and others inhibit certain functions.

Now lets talk about Alcohol

Although scientist don’t have a complete understanding of HOW exactly Alcohol affects the nervous system, we have a pretty decent understanding of SOME of the effects. What we do know is that mood altering substances, such as alcohol, influence neurotransmitter activity. We also know some of the specific neurotransmitters that alcohol has its effect on.


This neurotransmitter is a “feel-good” molecule and is very intimately related to your sense of well-being, which is tied to depression. An individual with low levels of serotonin is more likely to become depressed. This is one of the neurotransmitters that alcohol affects. It actually increases the serotonin levels in the brain, which is one of the reasons for the addicting effect of alcohol.


Dopamine is another excitatory neurotransmitter and is also considered to be a “feel-good” molecule. One of the effects of alcohol is to increase dopamine levels, which also contributes to the addictive effect of alcohol.

GABA (gamma-aminobutyric acid)

GABA is an inhibitory neurotransmitter in the brain. Alcohol increases GABA activity, which in turns inhibits brain activity. This is one of the main reasons why alcohol is refered to as a depressant. The statement “don’t drink and drive” is in response to this effect, because response time is usually increased. Someone under the influence of alcohol is less likely to respond quick enough to avoid accidents.


This is one of the most important excitatory neurotransmitter in the nervous system. Alcohol affects the receptor for glutamate, which reduces glutamate activity. Glutamate is also highly involved in muscular function, so when it’s activity is supressed, it results in slurred speech, discoordination and a number of other potentially dangerous effects.

Those are some of the effects of Alcohol on the nervous system. However, keep in mind that there is still lots to learn. The take home message is that alcohol isn’t a friend of the nervous system. This article is not meant to address whether or not you should drink. The focus is primarily to show you the physiological effects of alcohol on the nervous system. Keep in mind that we haven’t gotten into the effects on the other systems in the body, but in general, it’s not a good thing.

Questions or Comments?

If you have any questions or comments about how this process works, or what I’ve written here, please post them below in the comments section.

About The Author

Leslie Samuel

Leslie Samuel is the creator of Interactive Biology. His mission is to use this site to Make Biology fun for people all over the world.

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