Long-term use of either cannabis or cannabis-based drugs impairs memory, say researchers who found that mice exposed to the drug long-term had “significant memory impairments” and could not even discriminate between a familiar object and a novel one.
The researchers, from Lancaster and Lisbon Universities, studied the effects of the cannabinoid drug WIN 55,212-2 in mice, and believe their study has implications for people who use cannabis-based drugs to combat chronic pain and other conditions.
More and more people are using the drug long-term due to its legalization in several countries, while more potent varieties are available for recreational users.
Here’s what the researchers found:
- Long-term exposure impairs learning and memory in the animals
- Brain imaging studies showed that the drug impairs function in key brain regions involved in learning and memory
- Long-term exposure to the drug impairs the ability of brain regions involved in learning and memory to communicate with each other, suggesting that this underlies the negative effects of the drug on memory
Dr. Neil Dawson, the lead researcher from Lancaster University said “This work offers valuable new insight into the way in which long-term cannabinoid exposure negatively impacts on the brain. Understanding these mechanisms is central to understanding how long-term cannabinoid exposure increases the risk of developing mental health issues and memory problems.”
He also highlighted the relevance of the work to those using cannabinoid-based therapies to treat medical conditions like chronic pain and others.
“Cannabis-based therapies can be very effective at treating the symptoms of chronic diseases such as epilepsy and multiple sclerosis, and dramatically increase the quality of life for people living with these conditions. We need to understand the side effects that these people may experience so that we can develop new interventions to minimize these side effects”.
Professor Ana Sebastiao, lead researcher at the University of Lisbon, said: “As for all medicines, cannabinoid based therapies have not only beneficial disease-related actions, but also negative side effects. It is for the medical doctor to weight the advantages of the therapy, taking into consideration quality of life and diseases progression, against the potential side effects.”