Researchers uncover changes in brain activity associated with binge drinking.
Alcoholic beverages are consumed worldwide, but drinking to excess and with regularity carries a number of health warnings.
Binge drinking is defined by the National Institute on Alcohol Abuse and Alcoholism as five or more drinks for men and four or more drinks for women over a 2-hour period.
Aside from negative health outcomes, binge drinking also increases the risk of unintentional injuries, risky sexual behavior, and being involved in violence.
An estimated 1 in 6 adults in the United States binge drinks four times every month, consuming an average of eight drinks per session. It is most common in young adulthood but can continue across the lifespan.
Previous studies have also shown that, during cognitive tasks, individuals who binge drink perform significantly worse. For example, spatial working memory and executive function have both been found to suffer.
To date, however, researchers have not investigated whether or not there are measurable changes in a binge drinker's brain at rest.
The binge drinker's brain
Researchers from the University of Minho in Portugal - led by Eduardo López-Caneda - set out to investigate measurable differences in the brains of binge drinkers when not carrying out tests. Their findings are published this week in the journal Frontiers in Behavioral Neuroscience.
As López-Caneda explains, "A number of studies have assessed the effects of binge drinking in young adults during different tasks involving cognitive processes such as attention or working memory. However, there are hardly any studies assessing if the brains of binge drinkers show differences when they are at rest, and not focused on a task."
Students are well known for spending time socializing and partying - activities that are sometimes accompanied by alcohol in excess. So, the researchers recruited 80 first-year undergraduate students from a university in Spain.
Participants were split into two groups: the first never indulged in binge drinking, while those in the second had indulged in a binge drinking session at least once in the previous month. Importantly, none met the criteria to be considered an alcoholic.
Electrodes were attached to the participants' heads to assess electrical activity across a number of brain regions.
Non-bingers' and bingers' brains compared
When the neural activity of the two groups was compared, there were significant differences. More specifically, there was a measurable increase in beta and theta oscillations in the right temporal lobe - particularly the parahippocampal and fusiform gyri - and the occipital cortex.
The parahippocampal gyrus is believed to play a part in coding and retrieving memories. The fusiform gyrus does not have a well-defined role to date but seems to be involved in recognition. The occipital cortex deals with processing visual information.
Interestingly, the increased activity in these areas mirrors those found in the brains of chronic alcoholics.
The researchers believe that the alterations in brain activity might be early signs of alcohol-induced brain damage. Changes in these regions may indicate a reduction in their ability to respond to external stimuli, which may hamper information processing.
Younger brains are still developing, and the researchers believe that this might make them more vulnerable to alcohol damage.
"These features might be down to the particularly harmful effects of alcohol on young brains that are still in development, perhaps by delaying neuromaturational processes."
Of course, this study opens up many new questions to be answered. So next, the team would like to confirm that the changes are down to the binge drinking and whether or not brain development is impaired over the long-term.
Because the changes seen in the brain mirror those found in chronic alcoholics, López-Caneda hopes that their findings will be used "to try to reduce alcohol consumption in risky drinkers" at a young age.