Cannabis and adolescence

December 17, 2009

Canadian teenagers are among the largest consumers of cannabis worldwide. The damaging effects of this illicit drug on young brains are worse than originally thought, according to new research by Dr. Gabriella Gobbi, a psychiatric researcher from the Research Institute of the McGill University Health Centre. The new study, published in Neurobiology of Disease, suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain.

"We wanted to know what happens in the brains of teenagers when they use cannabis and whether they are more susceptible to its neurological effects than adults," explained Dr. Gobbi, who is also a professor at McGill University. Her study points to an apparent action of cannabis on two important compounds in the brain - serotonin and - which are involved in the regulation of neurological functions such as mood control and anxiety.

"Teenagers who are exposed to cannabis have decreased transmission, which leads to mood disorders, as well as increased norepinephrine transmission, which leads to greater long-term susceptibility to stress," Dr. Gobbi stated.

Previous epidemiological studies have shown how cannabis consumption can affect behaviour in some teenagers. "Our study is one of the first to focus on the neurobiological mechanisms at the root of this influence of cannabis on depression and anxiety in adolescents," confirmed Dr. Gobbi. It is also the first study to demonstrate that consumption causes more serious damage during adolescence than adulthood.

Explore further: New drug acts as marijuana in the brain

Related Stories

New drug acts as marijuana in the brain

December 14, 2005

A McGill University study suggests a new anti-depressant drug works by raising levels of endocannabinoids -- similar to a substance found in marijuana.

Study: cannabis a double-edged sword

October 23, 2007

A new neurobiological study has found that a synthetic form of THC, the active ingredient in cannabis, is an effective anti-depressant at low doses. However, at higher doses, the effect reverses itself and can actually worsen ...

Study investigates cannabis use among university students

December 18, 2007

New information published in the Journal of Applied Biobehavioral Research explores University students’ motivations for using or not using cannabis and found various factors that might encourage use.

Highest cannabis users are Australians

October 20, 2009

(PhysOrg.com) -- A new Lancet paper co-authored by a UQ researcher states that Australians are the highest cannabis users in the world, only matched by USA and New Zealand.

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Cow embryos reveal new type of chromosome chimera

May 27, 2016

I've often wondered what happens between the time an egg is fertilized and the time the ball of cells that it becomes nestles into the uterine lining. It's a period that we know very little about, a black box of developmental ...

Shaving time to test antidotes for nerve agents

February 29, 2016

Imagine you wanted to know how much energy it took to bike up a mountain, but couldn't finish the ride to the peak yourself. So, to get the total energy required, you and a team of friends strap energy meters to your bikes ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

degojoey
not rated yet Dec 17, 2009
is that "damage" as bad as the liver cancer my father-in-law is dealing with from drinking his whole life? I bet you its not, because that pothead is gonna live to tell his tale, while this government lets MILLIONS of people self inflict damage to themselves via tobacco or liquor. At least this one HAS medical uses, can you say the same for the "allowable" substances?
Neurofreak
not rated yet Dec 20, 2009
This PR blurb is amazingly disingenuous. The study was done on adolescent rats, not humans, and did not even involve marijuana, but instead a synthetic marijuana analogue that has both a higher for CB1 receptors than marijuana does, and also happens to be structurally quite different.

This isn't to say that theres anything wrong with rat studies, or that inferences can't be made from chemical analogues but to say that "y causes x" is an oversimplification that comes pretty close to just being deceitful.

I go into a little more elaborate detail about this study at http://www.neuroi...m/?p=187

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.