Recent studies of the sensory effects of psychedelic drugs indicate druginduced sensitivity to minimal and ordinary stimulation. This kind of laboratory observation accords with subjective reports that psychedelicdrugged subjects' sensory experiences are intensified and that they are aware of qualities of sensory experience which they never were before. Paradoxically, these individuals also evidence an increased tolerance for strong stimulation. The paradox is explained by an experimentally derived model of differential excitation which indicates how psychedelic drugs act differently on parts of the brain. The literature on various aspects of laboratory and clinical research with psychedelic drugs is reviewed on the basis of this formulation.
Silverman J. Research With PsychedelicsSome Biopsychological Concepts and Possible Clinical Applications. Arch Gen Psychiatry. 1971;25(6):498-510. doi:10.1001/archpsyc.1971.01750180018004