According to researchers lead by Dr. David Kareken of Indiana University, beer releases dopamine--the neurotransmitter of pleasure--in the brain:
In the study, researchers gave 49 male volunteers a tiny taste (half an ounce, or 15 milliliters) of their favorite beer over the course of 15 minutes — enough to taste the beer but not enough to cause a change in blood-alcohol level or intoxication. At other times, the volunteers were given a sports drink or water, for comparison.
To study the effect of beer's taste on dopamine receptors, the researchers scanned the volunteers' brains using Positron Emission Tomography, which uses the radiation emitted by a radioactive chemical to produce a 3D image of the brain.
The scans revealed higher increases in dopamine after the men tasted beer compared with tasting the sports drink or water — suggesting that the taste of alcohol is enough to prompt a pleasurable response in the brain. The men also reported higher beer cravings after tasting beer than water or the sports drink.
(Photo: Berndt Rostad)