“In Gamblers, haloperidol [a dopamine antagonist that blocks a specific dopamine receptor, the D2 receptor] significantly increased self-reported rewarding effects of gambling, post-game priming of desire to gamble, facilitation of reading speed to Gambling words, and gambling-induced elevation in blood pressure. In Controls, haloperidol augmented gambling-induced elevation in blood pressure, but had no effect on other indices. The findings provide direct experimental evidence that the D2 substrate modulates gambling reinforcement in pathological gamblers.”