CBD linked to increased blood flow to memory-related brain regions

Cannabidiol appeared to increase cerebral blood flow to brain regions involved in memory processing, according to results of an MRI study published in Journal of Psychopharmacology.

“The proposed effects of CBD on regional [cerebral blood flow] in humans have been disputed,” Michael A. P. Bloomfield, of the Institute of Mental Health at University College London, and colleagues wrote. “Previous studies have directly measured CBD-related changes in regional [cerebral blood flow] using SPECT, an imaging modality with relatively low resolution to investigate regional effects. Additionally, no study has investigated the association between regional [cerebral blood flow] and memory task performance under acute CBD.”

The investigators sought to determine the acute effects of CBD on cerebral blood flow in memory processing-related brain regions among 15 healthy individuals. They also aimed to investigate whether these effects were linked to differences in working and episodic memory task performance. In a randomized, crossover, double-blind design trial, they administered 600 mg oral CBD or placebo on different days and measured regional cerebral blood flow using a non-invasive measure, arterial spin labelling, 3 hours after drug ingestion Further, they used digit span and n-back tasks to assess working memory and a prose recall task to assess episodic memory.

Results showed an association between CBD and an increase in hippocampus cerebral blood flow. Bloomfield and colleagues reported no differences in memory task performance; however, they did note a significant link between greater CBD-induced orbitofrontal cerebral blood flow increases and an associated reduced reaction time on a two-back working memory task.

“These findings may have implications for the potential use of CBD across a range of disorders associated with hippocampal dysfunction, including Alzheimer’s disease, PTSD and depression,” the researchers wrote.