The disruption of the temporal distribution of investigatory responses by rats in a novel hole-board following lysergic acid diethylamide-25 (LSD), as described in a companion paper (Geyer and Light, 1979), was found to be a characteristic effect of a variety of hallucinogens. Similar effects were produced by indoleamine hallucinogens, such as LSD, N,N-dimethyltryptamine, and psilocin, and by...
To test the possible involvement of serotonin-containing cells of the midbrain in mediating the effects of mescaline on startle responding, electrolytic lesions were made in either the dorsal or median raphe nucleus in rats. Decreases in either striatal or hippocampal tryptophan hydroxylase activity confirmed the effectiveness of the lesions. One week later, startle was measured in response to...
Tactile startle responding by male Sprague-Dawley rats given 60 presentations of air-puff stimuli (37.5 psi) was measured after the intraperitoneal administration of graded doses of hallucinogens and other psychoactive drugs. Among the drugs tested were the indoleamine-derived compounds, lysergic acid diethylamide (LSD), N,N-dimethyltryptamine and psilocin, and the phenylethylamine-derived...