The Effects of Marijuana

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Practically everybody, whether doctor or layman, pothead or puritan, has been expressing dogmatic opinions for years about the effects of marijuana on its users. It therefore came as a surprise last week when a team of Harvard and Boston University investigators reported that they had just conducted the first truly scientific tests ever made on the subject. Their findings, which appear in Science magazine, confirm some popular ideas about marijuana's effects and expose others as completely false. The drug, the investigators concluded, "appears to be a relatively mild intoxicant, with minor, real, shortlived effects." It seems to have a greater effect on thinking and perception than on reflexes and coordination.

The leader of the research team was Andrew T. Weil, 26, a senior medical student at Harvard who graduated last summer and is now an intern at San Fran cisco's Mount Zion Hospital. Weil hopes to make a career of research into drugs that influence the mind. With marijuana, he learned—the hard way—about some of the research difficulties involved. Pos session or use of marijuana is illegal, except by hard-to-get federal dispensation. Universities are skittish about sponsoring research that might incur public or congressional criticism, and it took Weil a frustrating year to get the study approved and organized. Then he did it up right: he got his marijuana from the Federal Bureau of Narcotics and Dangerous Drugs itself, and got the attorney general of Massachusetts to agree that nobody would be arrested for taking part in the experiments. (See pictures of modern cannabis culture.)

Inhale Deeply. Weil organized two study groups composed of men aged 21 to 26 who had no known psychiatric disorder. Nine of the men had never smoked marijuana (although most said they had wanted to); the other eight were regular users.

Instead of using a psychedelic setting in a dimly lit pad, the researchers ran their tests in a square but comfortable laboratory. They rolled their own cigarettes of three kinds: one of low-strength marijuana, one of high-strength and a third of male hemp stalks, which gave off the same odor but contained none of the psychoactive ingredient. The subjects smoked two reefers within a few minutes in each three-hour session, which included both psychological and physiological tests. The study was double-blind—neither the testers nor the smokers knew, until afterward, which were the dummies and which the weak and strong reefers. The subjects smoked the different kinds of cigarettes in random order at successive sessions.

Red Eyes. The first thing that became clear was that those who had never smoked marijuana before got no reaction in their first session on pot. This tallies with the experience of many unscientific potheads; they achieved no "high" the first time. The only exception to this was a man who had expressed a desire to get high—and did so quickly. He became euphoric and laughed continuously. Yet one subject who had said that he did not intend to get high never did, even in successive sessions that included heavy doses of marijuana.

Nor could the novices estimate the strength of their reefers. They guessed right eight times out of nine on the dummy cigarette, and six times on the mild reefer, but eight out of nine guessed "mild" when they were really getting a puff with a big clout.

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