Dopamine and Dope
• Health Issues
Dopamine is emerging as the primary brain chemical - the one chemical that rules us all -
Perhaps most fascinating to addiction researchers is how an increase in dopamine creates a craving — and an expectation of a reward. In a study published earlier this month in The Journal of Neuroscience, Volkow used a brain scan to look at the dopamine releases in 18 cocaine addicts while they watched two videos: one of nature scenes, the other of people using cocaine. Volkow found that dopamine increased while the addicts watched the cocaine video and that the severity of the increase matched their self-reported level of craving for the drug. “For these people, their lives and experience had taught them that when they see others using cocaine, they’re probably about to get rewarded with drugs, too,” Volkow told me. “So even though they consciously knew that they weren’t going to get cocaine after watching the video, their brains had learned to expect the reward.”
Scientists posit that cue-induced dopamine spikes and craving essentially overpower the brain’s well-meaning frontal cortex, which is responsible for planning and decision making. The institute on drug abuse is currently financing studies of medications that could potentially blunt that process, interfering with the release of dopamine when an addict sees a conditioned cue.