Role of cannabinoid receptors in memory storage

Studies have shown that delta 9-tetrahydrocannabinol, the principal psychoactive ingredient in marijuana, produces memory deficits similar to those produced by neurochemical lesions of the hippocampus. Such lesions impair performance in short-term spatial memory tasks learned prior to the lesion. Animals trained in the behavioral task following the lesion can still perform the task, but learn a different behavioral strategy. Cannabinoid agonists impair behavioral performance in a delay-dependent manner similar to that produced by lesions, but also shift the behavioral response strategy. A possible role for cannabinoid receptors and endogenous cannabinoids may thus be to regulate the storage (i.e., encoding) of information, as well as the means by which that information is retrieved.