April 20 (UPI) -- Researchers have found evidence that alcoholism can impact the reward system centers of the brain in women differently than it does in men.
The brain's reward system consists of a group of structures including the amygdala and the hippocampus, which reinforce beneficial experiences, are involved in memory and decision-making and have been known to be involved in the development of substance use disorders.
Researchers recruited 60 people for the study who had recovered from histories of long-term alcoholism, dividing them in half with 30 women and 30 men, and an equivalent group of nonalcoholic volunteers.
The participants with histories of alcoholism had been abstinent from alcohol for varying time periods ranging from four weeks to 38 years. Participants filled out medical histories, completed neuropsychological assessments and had MRI brain scans to assess changes in brain structure.
The study was conducted by researchers at Massachusetts General Hospital, or MGH, and Boston University School of Medicine, or BUSM, who report that the reward system structures in the brain are larger in alcoholic women than in nonalcoholic women, while those same structures are smaller in alcoholic men than in nonalcoholic men.
"Until now, little has been known about the volume of the reward regions in alcoholic women, since all previous studies have been done in men," Gordon Harris, of the 3D Imaging Service and the Center for Morphometric Analysis in the Martinos Center for Biomedical Imaging at MGH, said in a press release. "Our findings suggest that it might be helpful to consider gender-specific approaches to treatment for alcoholism."
Researchers found a negative association between the length of sobriety and the size of fluid-filled ventricles in the center of the brain, meaning there is potential recovery of the overall brain from the effects of alcoholism over time.
MRI scans showed the average sizes of reward regions of the brain of alcoholic men were 4.1 percent smaller than those of nonalcoholic men, but the average sizes of the same structures were 4.4 percent larger in alcoholic than nonalcoholic women.
Each year of sobriety was associated with a 1.8 percent decrease in the size of the ventricles in the brain suggesting that recovery from damage to the brain due to alcoholism is possible.
Researchers stated the study cannot determine whether the differences preceded or resulted from the development of alcoholism.
The study was published in Psychiatry Research Neuroimaging.