Even College Social Drinkers Can Experience Blackouts

Alcohol is still the most popular and widely used drug for college students. It is estimated that almost 75% of all college students are current drinkers, and many of them engage in binge drinking.

With that many students drinking to excess on a regular basis a certain percentage of them are going to experience memory blackouts, and that can present problems as these young drinkers engage in risky behaviors during those blackout periods.

People experiencing blackouts can make dangerous choices when their judgment, impulse control, and decision-making ability is impaired by intoxication. And, research shows that female students are at even greater risk of making hazardous choices during blackouts compared to male students.

Researchers at Duke University Medical Center conducted a survey of 772 college students to examine the issue of blackouts.

Almost Half Had Experienced a Blackout

Results of the email survey included:

• 74.2% of students drank within the past two weeks
• 9.4% had experienced a blackout in the past two weeks
• 40% had a blackout in the past 12 months

"This study shows that the common assumption that blackouts only happen to alcoholics is wrong," said Aaron White, Ph.D., an assistant research professor of psychiatry at Duke and lead author of the study. "It is very possible for social drinkers, such as the students we surveyed, to experience blackouts if they overdo their consumption of alcohol. The study suggests that college students are much more familiar with blackouts than many people, including us, assumed."

Frequency of Blackouts

The student group surveyed was evenly divided among freshmen, sophomores, juniors and seniors, and between males and females. All students included in the survey were 18 years or older.

The 19-point survey asked students for information on demographics, drinking habits, family history of problems with alcohol, the frequency of blackouts and the types of events the students later learned they had participated in during the blackout episode.

"During a blackout, an individual is capable of participating in salient, emotionally-charged events but will have no recollection of what has occurred," White reported. "Many students in the study indicated that they later learned they had engaged in a wide range of risky activities during their blackouts - such as having unprotected sexual intercourse, vandalizing property or driving a car - which could have led to serious health or legal consequences."

Making Hazardous Choices

White said that due to the high level of intoxication needed to experience a blackout, other psychological processes may also be impaired.

"Impairments in judgment, decision-making, and impulse control could lead an individual to make potentially hazardous choices during blackouts," White said.

The survey revealed that although female students drank less heavily than male students, they were just as likely to have blackouts, which could put them at greater risk for a variety of negative consequences.

A 2016 study published in the journal Alcoholism: Clinical and Experimental Research found that the strongest independent predictors of blackouts in the previous month were having used multiple drugs, having been drunk six or more times in the past month, frequent smoking, low body weight, and being female. Other important predictors included binge drinking six or more times in the past month and residing in a college dormitory.

Another study found that blackout binge-drinking led to an increase in sexual revictimization among college-aged women.

Rapid Consumption May Be a Key

The Duke researchers believe consuming large quantities of alcohol very quickly increases the risk of blackouts because it increases the drinker's blood alcohol content at a rate that catches the brain regions critical in the formation of memories unprepared to deal with that much alcohol.

A Dangerous Rite of Passage

"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 Consequences

"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."

The Duke scientists suggest that standard alcohol-awareness training for students should include more information about blackouts, why they happen, and the potential dangers.

"We want to provide students with information that will help them make good, informed decisions regarding their use of alcohol," said White. "It is important for students to know what blackouts are and what factors seem to increase the risk of blackout occurrence so that they can be avoided."