Researchers reported that alcoholism impaired the function of the amygdala, hippocampus, and other limbic regions that processed emotions. It also affected the superior frontal and supramarginal areas in the cerebral cortex that handled memories and socialization.
Alcoholism (also known as alcohol use disorder) affects more than 100 million people globally. In the U.S., 15.1 million adults suffer from the condition, according to a 2015 survey. The condition tends to afflict people who have difficulty controlling their emotions.
Despite its prevalence, experts lack a clear understanding of the emotional processing issues that contribute to its onset.
Further, most studies on brain abnormalities linked with alcoholism do not distinguish between men and women. Most researchers focus on either alcoholic men or groups that combined members of both genders. (Related: Alcohol, not cannabis, is the REAL gateway drug for teens, say experts.)
Earlier studies showed that men and women process emotions differently. In particular, these identified specific regions in the brain of alcoholics that had muted responses to emotionally-charged scenes.
Researchers from Boston University (BU), together with teams from VA Boston Healthcare System and Massachusetts General Hospital, investigated the potential relationships between alcoholism, gender, and emotion processing. They identified the variations between alcoholic men and alcoholic women when it came to the brain abnormalities.
Their experiment involved four groups of volunteers — alcoholic men and women who were abstaining from their addiction, and control groups of both genders with no history of alcoholism.
The abstinent alcoholic groups had not drunk alcohol for at least 21 days.
Each participant went inside a functional magnetic resonance imaging (fMRI) device that scanned his or her brain. While inside, the participant got shown a mix of neutral and emotionally-charged images. The latter featured cheerful, erotic, gruesome, or shocking scenarios.
The researchers analyzed the changes in the participants' brain activity after seeing the emotionally-charged images and the neutral ones. They also compared the results among the alcoholic and control groups.
“Our findings indicate that the experiences and mechanisms of AUD and addiction differ for men and women,” explained BU researcher Dr. Kayle Sawyer. She served as the corresponding author of the study, released online in eLife.
Sawyer's team found that the brain responses of abstinent alcoholic men to emotionally-moving images were weaker compared to female alcoholics. The muted activity appeared in the regions that processed memory, emotions, and social relationships. It also applied to all four types of imagery.
Furthermore, alcoholic men also experienced weaker brain responses than male participants with no history of alcoholism. However, alcoholic women displayed stronger brain activity than their non-alcoholic women.
“This study provides insights into emotional processing in alcoholism by examining the influence of gender on brain activation,” remarked Sawyer.
Both healthcare professionals and ordinary citizens treat alcoholics in the same way, regardless of the patient's gender. However, the results of the BU study showed that abstinent alcoholic men and women handled their emotions in different, and even opposing, ways.
Sawyer and her colleagues suggested that follow-up and future research determine if the differences appeared during the abstinence period. Additionally, interested researchers might look into the relationship between the brain response variances and the variations of alcoholism in men and women.
Further research might improve the prevention and treatment of alcoholism based on the patient's gender.