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February 1973

δ9-Transtetrahydrocannabinol and Natural Marihuana: A Controlled Comparison

Author Affiliations

Bronx, NY; Baltimore; Birmingham, Ala; Stanford, Calif; Washington, DC
From the Department of Psychiatry, Albert Einstein College of Medicine, Bronx, NY (Dr. Galanter), Department of Psychology, University of Maryland, Baltimore (Dr. Weingartner), departments of psychiatry, University of Alabama, Birmingham (Dr. Vaughan), and Stanford University, Stanford, Calif (Dr. Roth), and the Laboratory of Clinical Psychopharmacology, National Institute of Mental Health, Washington, DC (Dr. Wyatt).

Arch Gen Psychiatry. 1973;28(2):278-281. doi:10.1001/archpsyc.1973.01750320106016

Twelve long-term marihuana users were studied after smoking natural marihuana, synthetic δ9-transtetrahydrocannabinol (δ9-THC), and placebo cigarettes. The subjective, cognitive, and physiologic changes tended to be greater for marihuana than for δ9-THC, although the syndromes produced were very similar. There was also a marked placebo effect on subjective measures that is suggestive of the importance of learning in the marihuana subjective syndrome. The apparent deficit in memory produced by marihuana appeared to be due to an attentional decrement rather than one of longer-term information storage. Reaction time, both unrewarded and with a monetary incentive, was unaffected by the drugs.