Viewing Pot Paraphernalia Triggers Emotional Connections in Brains of Marijuana Users

The sight of drug paraphernalia will have a different effect on more active marijuana users than those who are unfamiliar with the drug, according to a recent study published in the journal Drug and Alcohol Dependence. Researchers from the University of Texas at Dallas found that reward centers of the brain are triggered when illicit drug users view different drug devices.

"We know that people have a hard time staying abstinent because seeing cues for the drug use triggers this intense desire to seek out the drugs," said Dr. Francesca Filbey, lead author of the study and professor at the Center for BrainHealth in the School of Behavioral and Brain Sciences, in a news release. "That's a clinically validated phenomenon and behavioral studies have also shown this to be the case. What we didn't know was what was driving those effects in the brain."

For the study, researchers conducted brain-imaging scans, using functional magnetic resonance imaging (fMRI) on 71 patients who regularly used marijuana. Just over half of the participants were classified as dependent users. As they were scanned, participants were either given a pipe or a pencil.

The images showed that the nucleus accumbens, otherwise known as the reward region of the brain, was activated in the users in response to the pipe. However, the strength of the activation was ultimately dependent on whether the participant was a dependent or non-dependent user.

"We found that the reward network is actually being driven by other areas unrelated to reward, like the areas in memory and attention or emotion," Filbey said.

Non-dependent users typically showed greater activation in the orbital frontal cortex and the hippocampus--areas that affect memory and attention. On the other hand, dependent users showed greater activation in the amygdala and anterior cingulate gyrus, which suggests a more emotional connection.

Furthermore, activation of these areas mimic those of nicotine, cocaine and other drug addictions, supporting the potential for marijuana addiction, despite previous findings that negate the drug's addictiveness.

Researchers said they hope that future studies can help them better understand the drug's impact on the brain.