Heavy drinking during teenage years may lead to lasting brain changes and memory deficits in adulthood, according to a new study.

According to the World Health Organization, more and more adolescents and young adults are participating in binge drinking - the consumption of four (five for men) or more drinks over approximately two hours. This may seem normal for teens that like to go out partying every weekend, but the study's findings suggest that high doses of alcohol during adolescence may continue to affect the brain even after the party's over.

The latest findings were published in The Journal of Neuroscience.

Researchers at the University of Massachusetts, Amherst tested the theory on rats rather than humans, finding that even as adults, animals given daily access to alcohol during adolescence had reduced levels of myelin - the protective coating on nerves that accelerates the transmission of electrical signals between neurons. These changes were observed in the prefrontal cortex, a region of the brain important in reasoning and decision-making.

Young male rats were given daily access to either sweetened alcohol or sweetened water for two weeks, not only affecting their myelin levels but also impacting their memory. Animals that were the heaviest drinkers also performed worse on a memory test later in adulthood.

"This study suggests that exposure to high doses of alcohol during adolescence could exert lingering, if not permanent, damage to selective brain fibers," Edith Sullivan, PhD, who was not involved with this study, said in a press release. "This damage might underlie persistent compromise of cognitive functions involved in learning and render youth vulnerable for later development of alcohol use disorders."

According to the US Centers for Disease Control and Prevention (CDC), excessive alcohol accounts for one in 10 deaths among adults age 20 to 64. Not only could heavy drinking lead to cognitive problems in humans like the study suggests, but it puts us at risk for breast cancer, liver disease, and heart disease over time.