Dependence alters the brain's response to pot paraphernalia

July 16, 2014, University of Texas at Dallas
Dr. Francesca Filbey, professor at the University of Texas at Dallas, found that drug paraphernalia triggers the reward areas of the brain differently in dependent and non-dependent marijuana users. Credit: The University of Texas at Dallas

New research from The University of Texas at Dallas demonstrates that drug paraphernalia triggers the reward areas of the brain differently in dependent and non-dependent marijuana users.

The study, published July 1 in Drug and Alcohol Dependence, demonstrated that different areas of the brain activated when dependent and non-dependent users were exposed to drug-related cues.

The 2012 National Survey on Drug Use and Health shows marijuana is the most widely used illicit drug in the United States. According to a 2013 survey from the Pew Research Center, 48 percent of Americans ages 18 and older have tried marijuana. The National Institute on Drug Abuse states that 9 percent of daily users will become dependent on marijuana.

"We know that people have a hard time staying abstinent because seeing cues for the 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. "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."

To find this effect, Filbey and colleagues conducted brain-imaging scans, called functional magnetic resonance imaging (fMRI), on 71 participants who regularly used marijuana. Just more than half of those were classified as dependent users. While being scanned, the participants were given either a used marijuana pipe or a pencil of approximately the same size that they could see and feel.

A comparison of the images revealed that the nucleus accumbens, the reward region in the brain, was activated in all users in response to the pipe. However, the strengths of the connections with other areas differed between dependent and non-dependent users.

"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 showed greater activations in the and hippocampus, suggesting that memory and attention were connected to the activation of the reward network. Dependent users had greater activations in the amygdala and anterior cingulate gyrus, suggesting a more emotional connection.

Additionally, the areas of the brain activated resemble activated for other addictions, such as nicotine or cocaine, lending greater support to the addictiveness of marijuana.

These findings suggest that marijuana abuse intervention needs to cater more specifically to a user's level of addiction.

"Clinicians treating people with problems with dependence should consider the different processes that trigger the reward response when determining possible pharmacological or behavioral interventions," Filbey said.

Explore further: Study finds link between marijuana abuse and blunted dopamine response

Related Stories

Study finds link between marijuana abuse and blunted dopamine response

July 15, 2014
(Medical Xpress)—People who use marijuana heavily experience a blunted response to dopamine, according to researchers at Brookhaven National Laboratory, New York University Langone Medical Center and the National Institute ...

Of non-marijuana drug users in the ER, nearly all are problem drug users

July 7, 2014
Of emergency patients who reported any drug other than marijuana as their primary drug of use, 90.7 percent met the criteria for problematic drug use. Among patients who reported cannabis (marijuana) as their primary drug, ...

NIDA review summarizes research on marijuana's negative health effects

June 5, 2014
The current state of science on the adverse health effects of marijuana use links the drug to several significant adverse effects including addiction, a review reports. The article, published today in the New England Journal ...

Casual marijuana use linked to brain abnormalities in students

April 15, 2014
Young adults who used marijuana only recreationally showed significant abnormalities in two key brain regions that are important in emotion and motivation, scientists report. The study was a collaboration between Northwestern ...

Army drug users twice as likely to use synthetic marijuana as regular marijuana

May 8, 2014
Social work researchers from the University of Washington have found that among a group of active-duty Army personnel who use illicit drugs, the most abused substance is synthetic marijuana, which is harder to detect than ...

Pot isn't harmless, top U.S. health official says

June 4, 2014
(HealthDay)—States joining the march toward marijuana legalization need to take a step back and consider the drug's adverse effects on health, the U.S. drug "czar" argues in a new paper.

Recommended for you

Marijuana use may not aid patients in opioid addiction treatment

December 4, 2017
Many patients who are being treated for opioid addiction in a medication-assisted treatment clinic use marijuana to help manage their pain and mood symptoms.

For opiate addiction, study finds drug-assisted treatment is more effective than detox

November 23, 2017
Say you're a publicly insured Californian with an addiction to heroin, fentanyl or prescription narcotics, and you want to quit.

Study finds medical cannabis is effective at reducing opioid addiction

November 17, 2017
A new study conducted by researchers at The University of New Mexico, involving medical cannabis and prescription opioid use among chronic pain patients, found a distinct connection between having the legal ability to use ...

Insomnia linked to alcohol-use frequency among early adolescents, says new psychology study

November 8, 2017
Insomnia is linked to frequency of alcohol use among early adolescents, according to new Rutgers University–Camden research.

Large declines seen in teen substance abuse, delinquency

October 25, 2017
More than a decade of data indicates teens have become far less likely to abuse alcohol, nicotine and illicit drugs, and they also are less likely to engage in delinquent behaviors, such as fighting and stealing, according ...

Trying to get sober? NIH offers tool to help find good care

October 3, 2017
The phone calls come—from fellow scientists and desperate strangers—with a single question for the alcohol chief at the National Institutes of Health: Where can my loved one find good care to get sober?

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.