Now that cannabidiol (CBD) is readily and legally available for research purposes, more and more studies are being carried out on the cannabinoid’s medicinal properties. The results of many of these studies have shown that CBD offers a variety of health benefits for the treatment of a wide variety of ailments.
In a 2020 study funded by a British Medical Association Foundation for Medical Research Margaret Temple Award, a team of researchers investigated the effect of CBD on cerebral blood flow (CBF) and how it relates to memory.
Healthy and strong CBF is important for human health. A decrease in CBF in the hippocampus, a key region in the brain that supports learning and memory, has been implicated in a variety of ailments. If CBD affects CBF in specific regions of the brain important for memory, it could have a range of beneficial applications.
In this study, researchers recruited 15 participants for a placebo-controlled, double blind, randomized study, including nine females and six males. Subjects were given either 600 mg of oral CBD or a placebo (inactive substance) on separate days in gelatin capsules.
Three hours after ingestion of CBD or placebo, researchers measured regional CBF at rest. They also tested working memory using the digit span and n-back tasks and episodic memory with a prose-recall task. These are common tests used to clinically evaluate learning and memory function.
Although the memory tasks showed no significant drug effect, the researchers found that CBD increases CBF in the hippocampus. Numerous disorders are aggravated or caused by decreased blood flow into the hippocampus, including Alzheimer’s disease and neuropsychiatric disorders.
It’s important to note that these results contradict the findings of other studies. And while measuring CBF is an important way to look at brain function, there are many different factors that influence CBF levels and therefore it is not a direct correlate with function, as CBD did not affect memory performance.
Image Credit: Anna Shvets
- Bloomfield M, et al. The effects of acute cannabidiol on cerebral blood flow and its relationship to memory: An arterial spin labeling magnetic resonance imaging study. Journal of Psychopharmacology. 2020;34(9):981-989.