The involvement of dopamine (DA) in drug reinforcement is well established, but much less
in known about its contribution to addiction. We have used positron emission tomography to
investigate in humans the role of DA in drug reinforcement, addiction and drug vulnerability.
We have shown that during drug intoxication increases in striatal DA are associated with the
drug's reinforcing effects only if the DA changes occur rapidly. These results corroborate the
relevance of drug-induced DA increases and of pharmacokinetics in the rewarding effects of …