Recent government reports showing the prevalence of binge-drinking in America – one in six Americans binge drink. What exactly it is about alcohol that is so addictive? A new study from California researchers suggest it’s a result of released compounds in our brains. Alcohol promotes the release of endorphins – proteins responsible for the feelings of pleasure and reward in the brain, according to research from the Ernest Gallo Clinic and Research Center, at the University of California, San Francisco.
The research is the first to show that endorphins are released in the brain regions of the nucleus accumbens and the orbitofrontal cortex when a human drinks alcohol, researchers said. The nucleus accumbens is a brain region linked to addictive behavior, and the orbitofrontal cortex is a brain region linked with decision-making.
“This is something that we’ve speculated about for 30 years, based on animal studies, but haven’t observed in humans until now,” study researcher Jennifer Mitchell, PhD, clinical project director at the Gallo Center and an adjunct assistant professor of neurology at UCSF, said in a statement. “It provides the first direct evidence of how alcohol makes people feel good.”
In the study, published in the journal Science Translational Medicine, researchers used PET imaging to look at the brains of 13 people who heavily drink and 12 people who do not heavily drink. For all the people, researchers saw in the brain scans that endorphins were released in the brain in response to alcohol consumption. The more endorphins released in the brain region of the nucleus accumbens, the more pleasure the user reported experiencing, researchers said.
However, there was a more pronounced effect for the heavy drinkers – it turns out when those drinkers had more endorphins released in the brain region of the orbitofrontal cortex, the more intoxicated they felt, according to the study. This finding suggests that heavy drinkers have brain changes that lead to increased feelings of pleasure from alcohol consumption, researchers said. BBC News reported that alcohol also triggers dopamine release in the brain, a chemical known to spur satisfying feelings.