Neurotransmitters are the workhorse chemicals which allow the transmission of signals from one neuron to the next across nerve endings. The study revealed reductions in the activity of some major neurotransmitter genes at 24 hours after alcohol binge in adolescent animals. As adults, the animals showed even greater reductions, averaging 73 percent.
"Our findings suggest that human individuals who drink heavily during adolescence may be more likely to have deficits in being able to adapt successfully to changing life situations as adults, possibly tied to chemical and or structural changes in the frontal cortex," Crews said. "This is the part of the brain that allows us to predict consequences of our actions, control our impulses, refine our reasoning, and evaluate long- and short-term rewards."
Crews points out that just because the brain changes observed in his experiments are subtle, implications for individuals with a binge-drinking history may be immense.
"There is no discussion about the long-term consequences of underage drinking. There's discussion about alcohol intoxication risks during this transient period of life, because it's clear that kids who are driving are more likely to have accidents, or kill themselves, or engage in other inappropriate behaviors," he said. "But no one talks about how you might become a less intelligent, moody, or impulsive individual."
As Crews suggests, getting into an impulsive fight resulting in legal consequences, jail time, can change one's life course. "You might be more likely to tell your boss he's a jerk, and that could affect the course of your life. But while these subtle brain changes are not making you a monster, they're making you a less talented person or a person more prone to do stupid things whether you're drinking or not."
|Contact: Les Lang|
University of North Carolina School of Medicine