UWO researchers have identified the mechanism that causes marijuana smokers to become paranoid.
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.
Laviolette and his team at the Schulich School of Medicine & Dentistry discovered that activating cannabinoid receptors directly in a region of the brain 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.
The findings 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, already associated with heavy marijuana use.