A free exploration test was used to examine the effects of LSD on investigatory responding and locomotor activity in a novel environment. Rats were injected with 20–30 μg/kg LSD or saline prior to being placed in a home cage. After 10 min, a door was opened permitting entry into a larger holeboard chamber where crossovers, rearings, hole pokes, and routes of locomotion were monitored. When...
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...