A new study may shed light on the potential long-term cognitive health impacts of consuming alcohol.
The study assessed the impact of alcohol on the brains of rodents and found that the substance can materially impact cognition, even after a long period of sobriety. The federally funded research was published in ScienceAdvances earlier this month.
Researchers at Johns Hopkins University began the study by exposing a group of rats to very high quantities of alcohol vapor, followed by three months during which no alcohol was administered. Following the three-month pause, the rats were given a simple test to assess their cognition. Compared to a second control group that was not given alcohol, the first group performed markedly worse.
Study author Patricia Janak, a Johns Hopkins University neuroscientist who studies the biology of addiction, says the results have provided “a new model for the unfortunate cognitive changes that humans with alcohol use disorder show,” per Johns Hopkins University blog, HUB.
“We know that humans who are addicted to alcohol can show deficits in learning and decision-making that may contribute to their poor decisions related to alcohol use. We needed an animal model to better understand how chronic alcohol abuse affects the brain. Knowing what is happening in the brain of an animal when they are having these decision-making difficulties will tell us what is happening in humans.”
The researchers say their results are the first time a study on the impacts of alcohol on animals has revealed a drop in cognitive abilities. The authors theorize that previous studies may have employed tests that were too easy, failing to tease out the impact.
“Our experiment was quite challenging, and the alcohol-exposed rats just couldn’t do it as well,” Janak said.
“When the right answer was constantly changing, the control rats made the best decisions faster. They were more strategic. And when we looked at their brains, the control rats’ decision-related neural signals were stronger.”
Notably, the study found that the impact on cognition can persist for months. This may be one of the reasons relapse rates among people who have struggled with alcohol are so high.
“Alcohol-induced neural deficits may contribute to decisions to drink even after going to rehab. We can clearly demonstrate these deficits can be long-lasting,” said Janak.
While the researchers only found the impairment in male rats, they do not necessarily believe females are immune to the phenomenon. Instead, they suspect sex-related sensitivities may play a role in differing effects on brain function of long-term alcohol use.