About Careers Internship MedBlog Contact us
Medindia LOGIN REGISTER
Advertisement

Heavy Cannabis Use Linked With Reduced Dopamine Release in Brain

by Dr. Trupti Shirole on April 17, 2016 at 8:24 PM
Font : A-A+

 Heavy Cannabis Use Linked With Reduced Dopamine Release in Brain

Previous studies have shown that addiction to other drugs of abuse, such as cocaine and heroin, leads to compromised dopamine system. But, such evidence for cannabis was missing until now.

In a recent study, researchers found evidence of a compromised dopamine system in heavy users of marijuana. Lower dopamine release was found in the striatum - a region of the brain that is involved in working memory, impulsive behavior, and attention.

Advertisement


"In light of the more widespread acceptance and use of marijuana, especially by young people, we believe it is important to look more closely at the potentially addictive effects of cannabis on key regions of the brain," said Anissa Abi-Dargham, professor of psychiatry (in radiology) at Columbia University Medical Center (CUMC) and a lead author of the paper.

The study included 11 adults between the ages of 21 and 40 who were severely dependent on cannabis and 12 matched healthy controls. On average, the cannabis group started using at age 16, became dependent on cannabis by age 20, and have been dependent for the past 7 years. In the month prior to the study, nearly all users in this study smoked marijuana daily.
Advertisement

Using positron emission tomography (PET) to track a radiolabelled molecule that binds to dopamine receptors in the brain, the scientists measured dopamine release in the striatum and its subregions, as well as in several brain regions outside the striatum, including the thalamus, midbrain, and globus pallidus. The cannabis users in this study stayed in the hospital for a week of abstinence to ensure that the PET scans were not measuring the acute effects of the drug. Participants were scanned before and after being given oral amphetamine to elicit dopamine release. The percent change in the binding of the radiotracer was taken as an indicator of capacity for dopamine release.

Compared with the controls, the cannabis users had significantly lower dopamine release in the striatum, including subregions involved in associative and sensorimotor learning, and in the globus pallidus.

The investigators also explored the relationship between dopamine release in a key area of the striatum and cognitive performance on learning and working memory tasks. Although there was no difference between groups in task performance, in all participants lower dopamine release was associated with worse performance on both tasks.

"We don't know whether decreased dopamine was a preexisting condition or the result of heavy cannabis use," said Dr.Abi-Dargham. "But the bottom line is that long-term, heavy cannabis use may impair the dopaminergic system, which could have a variety of negative effects on learning and behavior."

Jeffrey Lieberman, Chair of Psychiatry at CUMC and past president of the American Psychiatric Association, noted that these findings add to the growing body of research demonstrating the potentially adverse effects of cannabis, particularly in youth, at the same time that government policies and laws are increasing access and use.

Source: Eurekalert
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
What's New on Medindia
Anemia among Indian Women and Children Remains a Cause of Concern- National Family Health Survey-5
H1N1 Influenza Prevention in Children: What Parents Need to Know
Dietary Factors Responsible for Dihydrotestosterone (DHT) Production and Hair Loss
View all
Recommended Reading
News Archive
Date
Category
Advertisement
News Category

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Parkinsons Disease Parkinsons Disease Surgical Treatment Cannabis Drug Abuse Screening Test Drug Abuse Brain Brain Facts Ataxia Language Areas in The Brain Ways to Improve your Intelligence Quotient (IQ) 

Most Popular on Medindia

Selfie Addiction Calculator A-Z Drug Brands in India Daily Calorie Requirements Diaphragmatic Hernia How to Reduce School Bag Weight - Simple Tips Drug Interaction Checker Blood Pressure Calculator Hearing Loss Calculator Drug Side Effects Calculator Turmeric Powder - Health Benefits, Uses & Side Effects
This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use
×

Heavy Cannabis Use Linked With Reduced Dopamine Release in Brain Personalised Printable Document (PDF)

Please complete this form and we'll send you a personalised information that is requested

You may use this for your own reference or forward it to your friends.

Please use the information prudently. If you are not a medical doctor please remember to consult your healthcare provider as this information is not a substitute for professional advice.

Name *

Email Address *

Country *

Areas of Interests