In a study posted online in the journal Neuroscience, scheduled for publication on November 8, lead author Megan Anderson, a graduate student working with Dr Tracey J Shors, Professor II in Behavioral and Systems Neuroscience in the Department of Psychology at Rutgers, reported that moderate to binge drinking – drinking less during the week and more on the weekends – significantly reduces the structural integrity of the adult brain.
“Moderate drinking can become binge drinking without the person realizing it,” said Anderson. “In the short term there may not be any noticeable motor skills or overall functioning problems, but in the long term this type of behavior could have an adverse effect on learning and memory.”
Shors and Anderson worked with postdoctoral fellow Miriam Nokia from the University of Jyvaskyla in Finland to model moderate to heavy drinking in humans. The rodents used in the trial voluntarily reaching a blood alcohol level of 0.08 percent, the legal driving limit in the United States and many other countries, and the point where brain cell production was affected negatively.
The researchers discovered that at this level of intoxication in rats – comparable to about 3-4 drinks for women and five drinks for men – the number of nerve cells in the hippocampus of the brain were reduced by nearly 40% compared to those in the abstinent group of rodents. The hippocampus is a part of the brain where the new neurons are made and is also known to be necessary for some types of new learning.
This level of alcohol intake was not enough to impair the motor skills of either male or female rats or prevent them from associative learning in the short term.
“This research indicates that social or daily drinking may be more harmful to brain health than what is now believed by the general public,” Anderson claims.