"Rather than inducing violent or aggressive behavior through its purported effects of lowering inhibitions, weakening impulse control and heightening aggressive tendencies, marihuana was usually found to inhibit the expression of aggressive impulses by pacifying the user, interfering with muscular coordination, reducing psychomotor activities and generally producing states of drowsiness lethargy, timidity and passivity."

Source

Shafer, Raymond P., et al, Marihuana: A Signal of Misunderstanding, Ch. III, (Washington DC: National Commission on Marihuana and Drug Abuse, 1972).
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