Looks like I'm not the only one with issues about dopamine. My ADD/depression/anxiety/self-hatred galaxy revolves around the stuff, and of course it's the mechanism of addiction. But these poor bastards found out that the medication they were taking for Parkinson's disease was turning them into pathological gamblers.
When the drug was discontinued, the urge to gamble disappeared. The AP story is here at Salon.com and the full scientific article from the Archives of Neurology is here.
That's a Holy Shit Moment, that a dopaminergic drug can cause that specific an addiction to a behavior.