Scientists spend a lot of time studying the brain, trying to learn more about how it works and why it works. One of the fascinating and challenging areas of study involving the brain looks at how alcohol affects this complex and amazing organ.
Human beings have been drinking alcohol in various forms for centuries. In that time, the everyday citizen and the scientist have learned a lot about how alcohol affects our thinking and our actions. General knowledge about alcohol and the brain is available from thousands of sources, written in terms that almost anyone can understand.
In addition, medical research has produced thousands of pages of information about alcohol and the brain. This knowledge shows that, in very general terms, alcohol can have effects that are hardly noticeable in everyday living. But alcohol can also have noticeable, long-lasting effects on brain function.
The most obvious effects of alcohol on the brain show up with violent behavior, impaired driving and walking, and in slurred speech or passing out. All of these situations can occur with excessive intake of alcohol.
Less obvious are the depressant effects of alcohol. The nervous system reacts more slowly and less naturally than when there is no alcohol present. The fact that people seem to talk faster and monopolize a conversation after a few drinks is misleading. People do “loosen up” after a few drinks. Research has shown that these smaller amounts of alcohol affect parts of the nervous system which normally keep our talking under control, for example.
However, with additional alcohol added to the system over time, the opposite begins to occur. In the brain, alcohol may alter the part of the brain that keeps us coordinated and balanced when walking and standing. Another part of the brain, the cortex at the front, can be affected by alcohol. When it is, we don’t reason well or understand things as well.
Early theories about how alcohol affects the brain pointed to chemicals in alcohol blocking the synapses (tiny gaps that nerve signals must cross). The electrical signals that pass to and from the brain are interrupted or delayed. Normal thinking and activity are affected.
Intense, detailed study shows that there are specific chemicals known as neurotransmitters are directly affected by alcohol. These neurotransmitters include dopamine, serotonin, glutamate and an acid known as GABA. Sometimes alcohol acts on these to make us feel as if there are rewards for alcohol consumption (dopamine). Serotonin may be involved in this process to some extent. But alcohol also acts on the brain with negative effects, inhibiting some of the normal actions of the body. In more general terms, alcohol slows or stops the normal activity of the brain and “depresses” the normal activity of the nervous system (throughout the body). The latest research on alcohol’s effects indicates that introducing alcohol to the brain might trigger “memory” of other drinking activity. Some scientists believe this is part of the reason for drinkers seeking familiar and comfortable places.