Study Finds Cannabidiol Improves Blood Flow To Parts Of The Brain Associated With Memory And Decision Making
CBD helps the mind: A single dose of cannabidiol (CBD) helped increase blood flow to the hippocampus, an important area of the brain associated with memory and emotions, according to a new study by researchers at UCL.
The researchers say the findings could be an important finding for conditions that affect memory, such as Alzheimer's disease and post-traumatic stress disorder (PTSD), and could help better target therapies.
In the study, published in the Journal of Psychopharmacology, researchers set out to study how CBD influences cerebral blood flow in different regions of the brain involved in memory processing.
Lead author Dr Michael Bloomfield (UCL Psychiatry) said: “Cannabidiol is one of the main constituents of cannabis and is gaining more and more interest because of its therapeutic potential. “There is evidence that CBD can help reduce symptoms of psychosis and anxiety. There is some evidence that CBD may improve memory functions. “Additionally, CBD alters the way the brain processes emotional memories, which may help explain its reputed therapeutic effects in post-traumatic stress disorder and other psychiatric disorders. However, the precise mechanisms underlying CBD's effects on memory are unclear ”.
For the randomized controlled study, 15 healthy young adults with little or no history of cannabis use were selected.
On different occasions, separated by at least a week, each participant was given 600 mg of oral CBD or a placebo. The doses were presented in identical capsules, so participants did not know which they were taking on which occasion.
The researchers measured blood flow to the hippocampus using "arterial spin labeling," a magnetic resonance imaging (MRI) scanning technique of the brain that measures changes in blood oxygen levels.

CBD dramatically increased blood flow in the hippocampus, but it did not cause significant differences in blood flow to other regions of the medial temporal lobe (MTL), of which the hippocampus is an important component.
In the prefrontal cortex, the area of the brain used for planning and decision making, CBD caused a significant increase in blood flow in the orbitofrontal cortex.
Dr Bloomfield added, “To our knowledge, this is the first study to find that CBD increases blood flow to key regions involved in memory processing, particularly the hippocampus.
“This supports the idea that CBD has effects on blood flow in the human brain that are region-specific, which has been disputed previously.
"If these results are reproduced, they could lead to further research in a range of conditions characterized by changes in the way the brain processes memories, most notably Alzheimer's disease, where there are flaws in the control of blood flow, as well as schizophrenia and post-traumatic stress disorder ”.
This study used a single dose of CBD in healthy volunteers, which may not translate into the effects of repeated dosing of CBD.
This research was funded by an award from the British Medical Association.