Acute cannabidiol (CBD), tetrahydrocannabinol (THC) and their mixture (THC:CBD) exert differential effects on brain activity and blood flow in rats: A translational neuroimaging study.
Journal of psychopharmacology (Oxford, England) March 1, 2026 Eilidh Macnicol, Michelle Kokkinou, Maria Elisa Serrano Navacerrada et al. 2 citations
THC increases brain functional connectivity and blood flow in rats, while CBD decreases connectivity without affecting blood flow. When combined, CBD moderates THC's effects. Adult male rats received THC, CBD, a combination, or a placebo. Brain scans two hours later showed THC raised whole-brain connectivity and blood flow in cortical and subcortical regions. CBD lowered connectivity metrics. The combination produced moderate increases in both measures. THC specifically strengthened connections between the cortex and hippocampus and between the cortex and striatum, an effect reduced when CBD was present. These distinct neurophysiological profiles suggest cannabinoids induce different brain states, supporting the use of functional neuroimaging in developing cannabinoid-based therapies.