Alcohol has lasting impact on memory in teenagers

Drinking alcohol heavily during adolescence results in long-lasting changes in parts of the brain that control learning and memory, says a study.

"In the eyes of the law, once people reach the age of 18, they are considered adult but the brain continues to mature and refine all the way into the mid-20s," explained lead author Mary-Louise Risher, post-doctoral researcher at Duke University.

It is important for young people to know that when they drink heavily during this period of development, "there could be changes occurring that have a lasting impact on memory and other cognitive functions," Risher noted.

The researchers periodically exposed young rodents to a level of alcohol during adolescence that, in humans, would result in impairment, but not sedation. Afterward, these animals received no further exposure to alcohol, and grew into adulthood -- which in rats occurred within 24 to 29 days.

Using small electrical stimuli applied to the hippocampus, a brain region where memory and learning are controlled, the researchers measured a cellular mechanism which is the strengthening of brain synapses as they are used to learn new tasks or conjure memories.

"Something happens during adolescent alcohol exposure that changes the way the hippocampus and other regions of the brain function and how the cells actually look," added senior study author Scott Swartzwelder, professor at Duke University.

(The study was published in the journal Alcoholism: Clinical & Experimental Research)