Hampson, et al., "Cannabidiol and delta-9-tetrahydrocannabinol are neuroprotective antioxidants," Proceedings of the National Academy of Sciences. 1998. 95:8268-8273.

Pharmos Corp. Announces Phase III Head Trauma Study. Marijuana Analog Benefits Brain Injured Patients.

Panikashvili, et al. "An endogenous cannabinoid (2-AG) is neuroprotective after brain injury" Nature. 2001. 413: 527-531. Exerpt:

Traumatic brain injury triggers the accumulation of harmful mediators that may lead to secondary damage. Protective mechanisms to attenuate damage are also set in motion. 2-Arachidonoyl glycerol (2-AG) is an endogenous cannabinoid, identified both in the periphery and in the brain, but its physiological roles have been only partially clarified. Here we show that, after injury to the mouse brain, 2-AG may have a neuroprotective role in which the cannabinoid system is involved. After closed head injury (CHI) in mice, the level of endogenous 2-AG was significantly elevated. We administered synthetic 2-AG to mice after CHI and found significant reduction of brain oedema, better clinical recovery, reduced infarct volume and reduced hippocampal cell death compared with controls. When 2-AG was administered together with additional inactive 2-acyl-glycerols that are normally present in the brain, functional recovery was significantly enhanced. The beneficial effect of 2-AG was dose-dependently attenuated by SR-141761A, an antagonist of the CB1 cannabinoid receptor.