A few years ago, a growing body of anecdotal evidence suggesting that cannabis wields an ameliorating effect on the symptoms of PTSD, prompted researchers at NYU’s Langone Medical Center to look more closely into the matter—literally: They irradiated the brains of a cohort of people, including veterans with PTSD so the parts that respond to cannabinoids (“CB 1 receptors”) would actually glow when activated.
If you think the next phase was to dose the volunteers with an infusion of THC or CBD, prepare to be disappointed. The focus of this study was not plant-derived cannabinoids (e.g. marijuana smoke) but endocannabinoids, our bodies’ own naturally occurring chemicals similar to the active ingredients in pot.
Peering inside the radioactive but marijuana-free brains, the researchers recorded lowered overall levels of one endocannabinoid, anandamide. They also discovered abnormally dense networks of CB1 receptors in the regions associated with fear and anxiety—which is just what you might expect in veterans suffering from PTSD. What was not necessarily expected is that the brains of the PTSD sufferers differed not just from those of the general population but also from those who had experienced trauma but not PTSD.
Up to 20 percent of vets returning from the Afghan and Iraq wars suffer from PTSD in any given year.
In other words, the research team may have just proved that PTSD is not merely an intense form of general anxiety but a dysfunction all its own—and they may have uncovered its unique biological markers. (If you prefer a higher proportion of Greek in your language, you can refer instead, as the report does, to the “neurobiological and functional endophenotypic correlates” of PTSD.)
The results of the study were published in the Sept. 2013 issue of Molecular Psychiatry. [You can download the unpoetically-titled Elevated Brain Cannabinoid CB1 Receptor Availability in Posttraumatic Stress Disorder: A Positron Emission Tomography Study here, but this press release is easier to digest. You can also download a 2015 followup translational report here.]
These results could have major implications for refining the way we diagnose and treat PTSD. For example, they might explain why the standard medications for anxiety don’t work so well for PTSD, and they may also point the way toward more targeted interventions.
That would be no small development. According to the Veterans Administration, up to 20 percent of vets returning from the Afghan and Iraq wars suffer from PTSD in any given year. And that’s in addition to the approximate 7 percent of the general population who have PTSD–without having gone to war.