Alcoholism, Neurologically Explained

Scientists are investigating the part of the brain that helps us learn moderation after a bad experience with alcohol or drugs. New research finds that an inhibition of this portion of the brain inevitably leads to alcoholism.

You know that little voice you hear in your head that says "absolutely never again" through the fog of a terrible hangover after drinking too much? According to a new study published in PLOS One, that little voice is actually your lateral habenula -- a portion of the brain that helps you resist the allure of alcohol and other drugs.

In the recent study, neuroscientists at the University of Utah sought to investigate that region, determining why it works well for some people, but proves nearly useless in reckless drinkers and drug abusers.

In order to investigate how essential the lateral habenula really is, researchers intermittently gave lab rats access to a solution of 20 percent alcohol over the course of several weeks.

The experimental group of rats -- rats who had their regulatory lateral habenula 'turned off' through isolated brain lesions, proved to drink far more alcohol over time, compared to rats with fully functioning brains.

In a second experiment, the researchers occasionally gave a similar group of rats sweet juice that was desirable to them, but when they did, they also injected the rats with enough alcohol to result in a hangover.

Soon enough, rats with healthy habenulas learned from their bad experiences, and began avoiding the juice. The rats with inactivated lateral habenulas, however, continued to seek the juice out. This indicated to scientists that a inactive or poorly functioning lateral habenula directly results in an inability to learn from undesirable experiences, such as a hangover or "bad trip."

According to the research team, it remains to be seen whether the lateral habenula regulates hangover effects, making people feel the adverse effect of drinking more strongly, or if it directly results in learning from negative experience, and more research looking into the subject is required.

Whether the lateral habenulas of alcoholic humans function poorly or differently compared to people with better self-regulation also remains a question waiting to be answered.

The study was published in PLOS One on April 2.