- Researchers gave 15 participants with no history of cannabis use 600mg of CBD on separate occasions for a week and then 600mg of a placebo
- CBD (cannabidoil) is the main non-psychoactive ingredient in marijuana that is believed to have responsible therapeutic effects such as pain relief
- MRI scans showed that CBD increased blood flow to the hippocampus responsible for memories and the orbitofrontal cortex responsible for decision making
- The team says this could provide therapies for people with conditions that affect memory, such as Alzheimer's
Just one dose of cannabidoil (CBD) has been found to improve blood flow to parts of the brain, a new small study suggests.
Researchers found that the main non-psychoactive ingredient in marijuana increased blood flow to the hippocampus, the area of the brain responsible for memories and learning.
It also increased blood flow to the part of the brain responsible for decision making.
The team, from the University of College London, say the findings could provide better targeted therapies for people with conditions that affect memory, such as Alzheimer's disease and post-traumatic stress disorder.
"To our knowledge, this is the first study to show that CBD increases blood flow to key regions involved in memory processing, particularly the hippocampus," said lead author Dr. Michael Bloomfield, a professor of psychiatry at UCL.
"This supports the view that CBD has region-specific blood flow effects in the human brain, which has previously been disputed."
THC and CBD
CBD and tetrahydrocannabinol (THC) both come from the cannabis plant. Together they are part of the cannabinoid group of compounds found in hashish, hash oil and most types of marijuana.
THC is the psychoactive compound responsible for the euphoric, "high" feeling often associated with marijuana.
The compound interacts with CB1 receptors in the central nervous system and brain, inducing feelings of euphoria and anxiety.
But CBD, which is not psychoactive, does not match these receptors well and is believed to be responsible for some of the therapeutic effects of marijuana, such as pain relief.
For the study, published in the journal Journal of Psychopharmacology, the team recruited 15 young and healthy participants with no history of cannabis use.
Over the course of a week, the adults received 600 milligrams (mg) of oral cannabis or a placebo.
Then, seven days later, they were given the capsule they had not taken. The participants did not know which capsule they were taking on each occasion.
Next, researchers used an MRI brain scanning technique called arterial spin labeling, which measures changes in the level of oxygen in the blood.
The results showed that CBD significantly increased blood flow in the hippocampus and orbitofrontal cortex, the latter of which plays a role in decision-making.
"Cannabidiol is one of the main components of cannabis and is gaining interest for its therapeutic potential," Bloomfield said.
There is some evidence that CBD can help reduce the symptoms of psychosis and anxiety. There is some evidence that CBD can improve memory function. '