"Because the cellular and biochemical mechanisms of action of psychoactive cannabinoids were not understood, neuroscientists were allowed great breadth to speculate upon the influence that these compounds might have on the neurons of the brain."

Howlett, A.C., Bidaut-Russell, M, Devane, W., Melvin, L., Johnsons, M., & Herkenham, M., "The Cannabinoid Receptor: Biochemical, anatomical, and behavioral characterization." Trends in Neuroscience13:10, 420-423. 1990. pg. 420.