Alcohol disrupts information processing in a variety of brain regions, including the hippocampus, which plays a critical role in the formation of memories of facts and events. The researchers suspect that consuming large amounts of alcohol quickly might increase the chances for a blackout because it leads to a rapid increase in the person's blood alcohol content. This catches the brain circuitry underlying memory formation unprepared to deal with an onslaught of alcohol.
When blood alcohol levels rise slowly, people seem to be less likely to experience blackouts even if they eventually become intoxicated. The researchers speculate that this might be due to a small degree of tolerance that develops during consumption of alcohol and could help protect the brain from blackouts.
"In college, in general, young people are living independently for the first time in their lives," said H. Scott Swartzwelder, Ph.D., clinical professor of psychiatry at Duke, a senior research career scientist with the U.S. Department of Veterans Affairs and a study co-author.
"With new freedoms, many adolescents go into an experimental mode which could include experimenting with alcohol and heavy drinking. Alcohol consumption is often viewed as a rite of passage for young adults and has become widely accepted throughout American culture, but people should be aware that the culture of drinking is quite different than it was some years ago. Many students today drink specifically to get drunk. This increases the risk of all sorts of consequences, including blackouts."
Long-Term Consequencies
According to the researchers, e-mail surveys have become more popular in recent years as a method of researching the habits and behaviors of college students because computers and e-mail have become mainstream tools for all college campuses. Students are comfortable using both computers and e-mail as a form of written communication, and e-mail surveys offer anonymity and a quick way to respond, they said.
"These study findings are very important because they support a large literature suggesting that students are consuming large quantities of alcohol and that they will suffer consequences," said Fulton T. Crews, Ph.D., director of the Center for Alcohol Studies at the University of North Carolina, Chapel Hill.
"Brain damage incurred during adolescence may become significant later in life as the processes of aging reduce the reserve capacity of individuals," he said. "Degenerative problems may become more prominent as people get older. So the risks of these types of episodes are not only the risks of trauma and harm during the blackout, but could include long-term consequences to health later in life."
Part One: Social Drinkers Can Blackout
