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High Culture:

  Marijuana in the Lives of Americans

    by William Novak

      Appendix II. Studies on the Effects of Marijuana in Users

I. The Weil-Zinberg Study

In 1968 Andrew Weil, then a medical student at Harvard University, together with Norman Zinberg, a Harvard psychoanalyst, conducted a series of experiments to determine the basic physical and psychological effects of marijuana on human beings This study, which took place at Boston University, represented the first double-blind experiments with marijuana; until the study was completed, neither the subjects nor the experimenters knew who had been smoking a drug and who had been smoking a carefully disguised placebo.
    Here are the conclusions, as reported in the article, "Clinical and Psychological Effects of Marihuana in Man," Science 162 (13 December 1968):1234-42.
    1. It is feasible and safe to study the effects of marijuana on human volunteers who smoke it in a laboratory.
    2. In a neutral setting persons who are naive to marijuana do not have strong subjective experiences after smoking low or high doses of the drug, and the effects they do report are not the same as those described by regular users of marijuana who take the drug in the same neutral setting.
    3. Marijuana-naive persons do demonstrate impaired performance on simple intellectual and psychomotor tests after smoking marijuana; the impairment is dose-related in some cases.
    4. Regular users of marijuana do get high after smoking marijuana in a neutral setting but do not show the same degree of impairment of performance on the tests as do naive subjects. In some cases, their performance even appears to improve slightly after smoking marijuana.
    5. Marijuana increases heart rate moderately.
    6. No change in respiratory rate follows administration of marijuana by inhalation.
    7. No change in pupil size occurs in short-term exposure to marijuana.
    8. Marijuana administration causes dilation of conjunctival blood vessels.
    9. Marijuana treatment produces no change in blood sugar levels.
    10. In a neutral setting the physiological and psychological effects of a single, inhaled dose of marijuana appear to reach maximum intensity within one-half hour of inhalation, to be diminished after one hour, and to be completely dissipated by three hours.

II. The Goode Study

In a study of 200 marijuana smokers conducted in 1967 and published in 1970 as The Marijuana Smokers, Erich Goode, a sociologist, reported the following results as the most common effects of smoking marijuana. The table appears in Goode's book Drugs in American Society (New York, 1972), page 48.

Subjective Effects of Marijuana: Goode 1970
More relaxed, peaceful, calmer46
Senses more "turned on," more sensitive, perceptive36
Think deeper, have more profound thoughts31
Laugh more; everything seems funnier29
Exaggeration of mood; things take on greater significance25
Time seems slowed down, stretched out23
Become withdrawn, introverted, privatistic22
Generally feel nice, groovy, pleasant, fun21
Mind wanders, free-associates; stream of consciousness21
Feel dizzy, light-headed20
Feel lazy, lethargic, don't want to move19
Feel light, airy, floating, elevated18
Feel "happy"18
Forget things, have memory gaps18
Feel freer, more unrestrained, less inhibited18
Stimulation of the senses is more enjoyable18
Become hungry, want to eat more; appetite stimulated17
Musical ear sharper, more acute, sensitive, accurate17
Enjoy music more; greater pleasure listening to music16
Feel paranoid15


III. The Tart Study

A year after The Marijuana Smokers appeared, Charles Tart, a California psychologist, published On Being Stoned: A Psychological Study of Marijuana Intoxication. Tart distributed 750 questionnaires among California smokers, of which 150 were returned. Tart used a forced-answer checklist, so that a higher percentage of respondents reported a specific effect than was true in Goode's study, where smokers had to think up the individual effects on their own. This table appears in Drugs in American Society, page 49.

Subjective Effects of Marijuana: Tart 1971
Hear subtle changes in sounds 9541
Distance walking seems changed 78213
Taste seems different 78181
Sleep easier and better76143
Enjoy eating more; eat more75231
Time passes slowly74241
Physically relaxed, inactive 72271
Can "come down" at will 70215
Feel more childlike, open 68265
Can understand songs better 66304
Sense of touch more exciting 65304
Accept things easier 64322
Hard to play social games 62286
Almost always feel good 61205
Memory span shortened 60363
Spatial separation of music 602713
Mind's eye sharper 602512
Difficult to read 57299
See visual patterns in things 56356
Sexual orgasm more pleasurable 56316
Meaningful insights come to mind 55403
Touch takes on new qualities 55395
Deeper insights into others 55387
Appreciate subtle humor in others 54432
Completely present-oriented 53443
Forget to finish things 53424
Moving about seems smoother 53377
Less boisterous at parties 52395
Aware of body-emotion connection 503613
Accept contradictions easier 503211


IV. Other Studies

In 1971 a survey conducted by three physicians (James Halikas, Donald Goodwin, and Samuel Guze) was described in the Journal of the American Medical Association z17: 6gz-g4. A hundred regular marijuana smokers were asked to complete a checklist questionnaire. This table was compiled by Erich Goode, and it appears in Drugs in American Society, page 51.

Subjective Effects of Marijuana: Halikas, Goodwin, and Guze 1971
Euphoria 82171
Relaxation 79210
Keener sound sense 76213
Peaceful 74251
Increased sensitivity 74233
Increased hunger 72244
Time slowed down 62353
Increased thirst 62326
Dry throat and mouth 61381
Floating sensation 45496
More talkative 375112
Hunger for sweets374320
Laughing and giggling 36604
Heightened sex feeling 34597
Heightened sex arousal 33598

    A fifth study was conducted by Joel Hochman and Norman Brill, physicians at the University of California at Los Angeles. In 1971 a random sample of UCLA's student body was asked to respond to a forced-alternative checklist, with two categories of marijuana use by frequency (often or always, and never) and two levels of use: chronic and occasional. This table was extracted by Erich Goode from the UCLA study and appears in Drugs in American Society, page 52.

Subjective Effects of Marijuana: Hochman and Brill 1971
Increased sex pleasure8350320
Decreased tension8257514
Intensified taste8065617
Intensified hearing7966615
Very happy (euphoria)7059312
Increased abstract thinking7046620
Time passes slowly6657618
Increased self-awareness62451119
Increased sexual appetite6043620
Desire for sweets55371129
Increased understanding of others47341427
Increased creativity45251635
Increased ability to communicate42251637
Clarifies thinking35201333
Decreased attention span28312830
Paranoid thoughts18192539
Able to function better1863152
Decreased ability to communicate17193337
Irrational ideas13163842
Dulls thinking12162834
Rapid heartbeat10145456
Shortness of breath447180
Increased tension377264
Decreased sexual appetite237570
Decreased sexual pleasure148578

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