It’s all too common for heavy drinkers and partygoers. The pounding headache, the nausea, the dizziness, and sometimes vomiting are all symptoms you may experience after a long night out on the town. It’s a feeling that can be so miserable you may never want to get drunk again, but somehow the drinks are still pouring at the next party.

Scientists discovered in a new study published in PLOS ONE why we experience hangovers. They say their findings are critical to helping alcoholics with their addiction. In the study, researchers used lab rats to test how alcohol affects their bodies, giving them a significant amount of strong alcohol over a few weeks, Daily Mail reports.

What they discovered was that the rats who drank heavier had a disabled lateral habenula. The lateral habenula is a region of the brain that is linked to depression and avoidance behaviors. It is also responsible for a hangover. Scientists say it is activated by bad experiences and, when underactive, people may be more likely to repeat unhealthy behavior.

“Rats with an inactivated lateral habenula sought out the juice more than control animals, even though it meant a repeat of the bad experience. If we can understand the brain circuits that control sensitivity to alcohol’s aversive effects, then we can start to get a handle on who may become a problem drinker," said lead researcher of the study, Professor Sharif Taha. From the rats, the scientists concluded that when the lateral habenula is inactivated, people are more likely to repeat heavy drinking despite their experiences.

Excessive drinking can cause accidents, falls, violence, miscarriages, and alcohol poisoning. Long-term health issues include liver damage, depression, dementia, and different cancers. Scientists from the University of Utah hope this research will help to treat alcoholism, a disease that affects thousands of people every year.