Scientists have used laser lights to turn cocaine cravings off and on in a study of rats. The findings suggest new directions for treatment of addiction in humans, according to the researchers from the National Institute on Drug Abuse (NIDA) and the University of California, San Francisco.

The laser light was used to stimulate a part of the prefrontal cortex in the animals’ brains, HealthDay reports. This part of the brain plays an important role in impulse control and decision making.

The researchers inserted light-sensitive proteins into nerve cells in the animals’ prefrontal cortex. They used the laser to turn the cells on and off. Turning the cells on eliminated the rats’ cocaine cravings, while turning them off triggered the craving.

Human studies likely will use electromagnetic stimulation outside the scalp, instead of lasers, to trigger activation of the prefrontal cortex, the article notes. Study co-author Dr. Antonello Bonci of the University of California, San Francisco, noted human studies are being designed.

“This exciting study offers a new direction of research for the treatment of cocaine and possibly other addictions,” NIDA Director Dr. Nora D. Volkow said in a news release. “We already knew, mainly from human brain imaging studies, that deficits in the prefrontal cortex are involved in drug addiction. Now that we have learned how fundamental these deficits are, we feel more confident than ever about the therapeutic promise of targeting that part of the brain.”

The findings appear in the journal Nature.