'Alcohol has long been revered for its power to get pretty anyone, after enough, to dance the "Macarena." It turns out that the hormone oxytocin might do the same thing — help people feel more extroverted — without the problems associated with alcohol, such as drunk driving, physiological damage and ordering pizza at 3 A.M.
In a study authored by Christopher Cardoso, participants inhaled either a placebo or the hormone oxytocin, which is the "bonding hormone" that sees a spike in women after childbirth. It is thought to help mothers bond with their children, but the study shows it also makes people feel more extroverted.
Again, it makes people feel more extroverted; it doesn't necessarily make them more extroverted. It's a perception-changing hormone, but that difference in perception can obviously lead to someone acting differently.'