Apr 9, 2025 10:11 PM
https://www.eurekalert.org/news-releases/1080010
INTRO: A McGill University-led study found that people with cannabis use disorder (CUD) had elevated dopamine levels in a brain region associated with psychosis.
“This could help explain why cannabis use increases the risk of hallucinations and delusions, key symptoms of schizophrenia and other psychotic disorders,” said first author Jessica Ahrens, a PhD student in McGill’s Integrated Program in Neuroscience.
Dopamine is a neurotransmitter that helps regulate mood and motivation, and an excess is associated with psychosis. While it was known that cannabis influences dopamine, this study clarifies where in the brain these changes occur. Cannabis use disorder is when someone has trouble controlling their cannabis use, continues despite negative effects, and may experience cravings or withdrawal.
“For a long time, clinical researchers across the world have been searching for a link showing that cannabis affects the brain mechanism behind psychosis. We now show that a shared dopamine pathway could be the answer,” Ahrens said.
The study involved 61 people, including those with and without cannabis use disorder, as well as individuals with early-stage schizophrenia, some of whom also had CUD. Using a specialized brain scan called neuromelanin-MRI, researchers at Western University measured their neuromelanin signal, which reflects dopamine activity.
People with CUD had an abnormally high neuromelanin signal, and the elevation was tied to the severity of their cannabis use. In contrast, those without schizophrenia or CUD did not show this increase. Larger studies are needed to confirm these findings... (MORE - details, no ads)
INTRO: A McGill University-led study found that people with cannabis use disorder (CUD) had elevated dopamine levels in a brain region associated with psychosis.
“This could help explain why cannabis use increases the risk of hallucinations and delusions, key symptoms of schizophrenia and other psychotic disorders,” said first author Jessica Ahrens, a PhD student in McGill’s Integrated Program in Neuroscience.
Dopamine is a neurotransmitter that helps regulate mood and motivation, and an excess is associated with psychosis. While it was known that cannabis influences dopamine, this study clarifies where in the brain these changes occur. Cannabis use disorder is when someone has trouble controlling their cannabis use, continues despite negative effects, and may experience cravings or withdrawal.
“For a long time, clinical researchers across the world have been searching for a link showing that cannabis affects the brain mechanism behind psychosis. We now show that a shared dopamine pathway could be the answer,” Ahrens said.
The study involved 61 people, including those with and without cannabis use disorder, as well as individuals with early-stage schizophrenia, some of whom also had CUD. Using a specialized brain scan called neuromelanin-MRI, researchers at Western University measured their neuromelanin signal, which reflects dopamine activity.
People with CUD had an abnormally high neuromelanin signal, and the elevation was tied to the severity of their cannabis use. In contrast, those without schizophrenia or CUD did not show this increase. Larger studies are needed to confirm these findings... (MORE - details, no ads)