Chunk #10 — Do cannabinoids cause short-lived positive psychotic symptoms, negative symptoms and cognitive deficits in the general population? — Experimental evidence
The first reported study was conducted under the direction of the “LaGuardia Committee on Marihuana” [147]. With cannabis doses of about 30–50 mg (oral) and 8–30 mg (smoked), 12.5% of subjects experienced psychotic reactions. However, these subjects were prisoners and their mental status cannot be presumed to be healthy. Ames [10] studied the effects of unassayed oral doses of cannabis extract (about 50–70 mg Δ9-THC) in 12 physicians who were presumably healthy. Subjects reported fragmented thinking, dissociation between thoughts and action, disturbed temporal and spatial perception, visual illusions and hallucinations, derealization and depersonalization, mood alterations, anxiety and memory deficits. Some subjects reported delusions of the presence of hidden recorders, fear of being hypnotized, fears of electroconvulsive therapy, and fears of developing schizophrenia. One subject refused to answer questions for fear of being certified as insane. Isbell and colleagues [103] studied the effects of varying doses of Δ9-THC in 40 former opiate addicts. At a dose of Δ9-THC, 120 μg/kg orally and 50 μg/kg smoking, in addition to recognizing the effects as being similar to cannabis, the subjects reported alterations in
