While you may certainly have heard of the term, alcoholism, perhaps less so of the medical condition known as alcohol use disorder (AUD). According to the National Institute on Alcohol Abuse and Alcoholism, AUD is a relapsing brain disease that is chronic involving the loss of control of alcohol intake. Alcoholism is a non-medical term and what most people use to describe AUD.
Knowing the detrimental effects of drinking can have on one’s life, what drives someone suffering from AUD to continue to drink? That’s what researchers of a new study published in eNeuro wanted to find out.
“If we can better understand this decision-making process and how it malfunctions in people with AUD,” study author David N. Linsenbardt told us, “it may be possible to design new treatments for AUD.”
To investigate these decisions, researchers used a specific strain of rats (“P” rats) that were bred to prefer to drink alcohol as a model of individuals with a family history of excessive drinking.
“We were hoping to find out: 1) if a particular area of the brain (known as the medial prefrontal cortex; mPFC) was involved in decisions to consume alcohol,” Linsenbardt told us, “and 2) if this process was different in animals with increased risk of excessive alcohol consumption due to a family history of excessive drinking.”
It has been previously shown that having a family history of an alcohol use disorder greatly increases one’s risk of developing the disease. Furthermore, past research shows that the part of the brain that the researchers studied (mPFC) is involved in planning future actions and decision-making.
“Based on these findings, our hypothesis going into this study was that brain activity in mPFC would better predict future alcohol drinking in individuals who had a long family history of drinking alcohol excessively (the “P” rats) compared to a population without this increased risk (another strain of rats called Wistars),” Linsenbardt told us. “We refer to this predictive signal as an ‘intention’ to drink signal. So, we expected that P rats would show a stronger intention to drink alcohol due to their family history relative to Wistars.”
Linsenbardt and his colleagues chose to study this topic in particular because of the huge detrimental impact alcohol use disorders have on individuals and society. According to the National Survey on Drug Use and Health, over 15 million adults in the U.S. aged 18 and older had alcohol use disorder (AUD) when the survey was done in 2015.
“Our hope is that developing an understanding of the neural mechanisms of excessive alcohol drinking may lead to novel treatments and interventions targeting these malfunctioning brain processes to help people suffering from this disease,” Linsenbardt told us.
To test their hypothesis, researchers recorded the electrical activity of brain cells in rats as they decided whether or not drink alcohol.
“As often happens in science, we found almost the exact opposite of what we expected,” Linsenbardt told us. “We found that the electrical activity of brain cells in Wistar rats (not P rats, as we had expected) predicted if they would drink alcohol, but in P rats the ability to predict drinking from electrical activity was either reduced or completely absent. Thus, vulnerability to excessive alcohol consumption in those with a family history may be in part due to lack of neural encoding of alcohol drinking intent.”
The results took Linsenbardt and his colleagues by surprise.
“We are often surprised with the results of our studies,” Linsenbardt told us, “but this one was completely counter to our hypothesis.”
Based on the results, Linsenbardt and his colleagues hypothesize that the lack of intention signal may be a key reason why people suffering from an AUD continue to decide to drink.
“We are in the process of following up on these results using more advanced experiments,” Linsenbardt told us, “but if a causal link is identified between the drinking intention signal and excessive alcohol consumption, our hope is that these results will lay the groundwork for novel medications and/or behavioral treatments for AUD.”
Patricia Tomasi is a mom, maternal mental health advocate, journalist, and speaker. She writes regularly for the Huffington Post Canada, focusing primarily on maternal mental health after suffering from severe postpartum anxiety twice. You can find her Huffington Post biography here. Patricia is also a Patient Expert Advisor for the North American-based, Maternal Mental Health Research Collective and is the founder of the online peer support group - Facebook Postpartum Depression & Anxiety Support Group - with over 1500 members worldwide. Blog: www.patriciatomasiblog.wordpress.com