In an experiment Guiora et al. (1972) attempted to mitigate the empathy level of their subjects by administering increasing amounts of alcohol. They found that the subjects’ pronunciation of the target language improved and then decreased as they drank increasing amounts of alcohol. Dull and Scovel (1972) demonstrated that very small amounts of alcohol (1 ounce) improved pronunciation in half of the subjects.
"Replications of this experiment were subsequently carried out using hypnosis and valium. In the first case - reported in Schumann et al. (1978) - it was found that deeply hypnotised subjects performed significantly better than less hypnotised subjects on an L2 pronunciation test, which may indicate that a willingness "to let go" is a good predictor of L2 pronunciation performance....
The valium study - reported in Guiora et al. (1980) - produced less clear-cut results, but did yield further evidence that relaxation, anxiety reduction and disinhibition, in this instance brought about by the administration of a psychotropic drug, were associated with improved L2 pronunciation."
Language acquisition: the age factor By David Michael Singleton, Lisa Ryan
Don't drink and drive and don't try to prove or disprove this by experimenting with alcohol. The point is that you need to relax, get into it and "let go".