Research discovers how marijuana affects the way the brain processes emotional information

April 5, 2011, University of Western Ontario

Drugs like marijuana act on naturally occurring receptors in the brain called cannabinoid receptors. However, the mechanisms by which these drugs produce their sensory and mood altering effects within the brain are largely unknown. Research led by Steven Laviolette at The University of Western Ontario has now identified a critical brain pathway responsible for the effects of cannabinoid drugs on how the brain processes emotional information. The findings, published in The Journal of Neuroscience, also help to explain the possible link between marijuana use and schizophrenia.

Laviolette and his team at the Schulich School of Medicine & Dentistry discovered that activating cannabinoid receptors directly in a region of the called the amygdala, can strongly influence the significance of emotional information and memory processes. It also dramatically increased the activity patterns of neurons in a connected region of the brain called the prefrontal cortex, controlling both how the brain perceived the emotional significance of incoming sensory information, and the strength of memories associated with these emotional experiences.

Neuroscientist Steven Laviolette of the Schulich School of Medicine & Dentistry at the University of Western Ontario has identified the brain pathway responsible for the effects of drugs like marijuana on how the brain processes emotional information. This may also explain evidence of a link between heavy marijuana use and the increased risk of developing schizophrenia. Credit: The University Of Western Ontario

"These findings are of great clinical relevance given recent evidence suggesting that exposure to marijuana during adolescence can increase the likelihood of developing schizophrenia later in life," says Laviolette, an associate professor in the Department of Anatomy and Cell Biology. "We know there are abnormalities in both the amygdala and prefrontal cortex in patients who have , and we now know these same brain areas are critical to the effects of marijuana and other cannabinoid drugs on emotional processing."

Furthermore, the findings by Laviolette's laboratory identify a novel new brain pathway by which drugs acting on the cannabinoid system can distort the emotional relevance of incoming sensory information which in turn may lead to psychotic side-effects, such as paranoia, associated with heavy use. Developing pharmacological compounds, and there already are some, that block or modify this pathway could help control psychotic episodes. It could also be used to help patients with Post Traumatic Stress Disorder who have difficulty controlling the resurgence of highly emotional events into their memory.

Related Stories

Recommended for you

Fragile X finding shows normal neurons that interact poorly

January 18, 2018
Neurons in mice afflicted with the genetic defect that causes Fragile X syndrome (FXS) appear similar to those in healthy mice, but these neurons fail to interact normally, resulting in the long-known cognitive impairments, ...

How your brain remembers what you had for dinner last night

January 17, 2018
Confirming earlier computational models, researchers at University of California San Diego and UC San Diego School of Medicine, with colleagues in Arizona and Louisiana, report that episodic memories are encoded in the hippocampus ...

Recording a thought's fleeting trip through the brain

January 17, 2018
University of California, Berkeley neuroscientists have tracked the progress of a thought through the brain, showing clearly how the prefrontal cortex at the front of the brain coordinates activity to help us act in response ...

Midbrain 'start neurons' control whether we walk or run

January 17, 2018
Locomotion comprises the most fundamental movements we perform. It is a complex sequence from initiating the first step, to stopping when we reach our goal. At the same time, locomotion is executed at different speeds to ...

Miles Davis is not Mozart: The brains of jazz and classical pianists work differently

January 16, 2018
Keith Jarret, world-famous jazz pianist, once answered in an interview when asked if he would ever be interested in doing a concert where he would play both jazz and classical music: "No, that's hilarious. [...] It's like ...

New study reveals why some people are more creative than others

January 16, 2018
Creativity is often defined as the ability to come up with new and useful ideas. Like intelligence, it can be considered a trait that everyone – not just creative "geniuses" like Picasso and Steve Jobs – possesses in ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Bob_B
1.5 / 5 (2) Apr 06, 2011
Perhaps Laviolette could "identify a novel new brain" for himself. Anyone thinking children need to get high on anything are idiots.

Articles like this can increase the likelihood of developing schizophrenia later in life for the author and editors.

wiyosaya
not rated yet Apr 06, 2011
@Bob B -
Anyone thinking children need to get high on anything are idiots.

And Laviolette says this in the article or the video where? Please point it out.

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.