"People typically drink alcohol to induce euphoria or reduce anxiety, and they frequently drink in social settings, yet the effect of alcohol on human brain circuits involved in reward and emotion has been explored only sparingly. We administered alcohol intravenously to social drinkers while brain response to visual threatening and nonthreatening facial stimuli was measured using functional magnetic resonance imaging (fMRI). Alcohol robustly activated striatal reward circuits while attenuating response to fearful stimuli in visual and limbic regions. Self-ratings of intoxication correlated with striatal activation, suggesting that activation in this area may contribute to subjective experience of pleasure and reward during intoxication. These results show that the acute pharmacological rewarding and anxiolytic effects of alcohol can be measured with fMRI."
"In addition, alcohol activated striatal areas of the brain that are important components of the reward system. This confirms previous findings and supports the idea that activation of the brain's reward system is a common feature of all drugs of abuse. Gilman's team found that the level of striatal activation was associated with how intoxicated the participants reported feeling. These striatal responses help account for the stimulating and addictive properties of alcohol."
Working with 12 healthy participants who drink socially, researchers used functional magnetic resonance imaging (fMRI) to study activity in emotion-processing brain regions during alcohol exposure. When participants received a placebo instead of alcohol, they showed greater activity in the amygdala, insula, and parahippocampal gyrus -- brain regions involved in fear and avoidance -- when shown a picture of a fearful facial expression.