A new study has revealed that people at high risk for alcohol-use problems showed a greater dopamine response in a brain pathway that increases desire for rewards than those who are at lower risk.
According to a new study by Prof. Marco Leyton, of McGill University's Department of Psychiatry, people vulnerable to developing alcoholism exhibit a distinctive brain response when drinking alcohol.
"There is accumulating evidence that there are multiple pathways to alcoholism, each associated with a distinct set of personality traits and neurobiological features," Leyton said.
For the study, researchers recruited 26 healthy social drinkers-18 men, 8 women, 18 to 30 years of age, from the Montreal area.
The higher-risk subjects were then identified based on personality traits and having a lower intoxication response to alcohol (they did not feel as drunk despite having drunk the same amount). Finally, each participant underwent two positron emission tomography (PET) brain scan exams after drinking either juice or alcohol (about 3 drinks in 15 minutes).
"We found that people vulnerable to developing alcoholism experienced an unusually large brain dopamine response when they took a drink," Leyton said.
"This large response might energize reward-seeking behaviours and counteract the sedative effects of alcohol. Conversely, people who experience minimal dopamine release when they drink might find the sedative effects of alcohol especially pronounced."
The study was published in the journal Alcoholism: Clinical and Experimental Research.