scales: Amphetamine, Benzedrine Group (BG), Marijuana, Lysergic Acid (LSD), Morphine-Benzedrine Group (MBG) and Pentobarbitol-Chlorpromazine-Alcohol Group (PCAG). Each of these 22 phenotypes was measured at six time points during three sessions (placebo, 10 and 20 mg), totaling 396 phenotypic values for each participant. This study was approved by the Institutional Review Board of The University of Chicago and was carried out in accordance with the Helsinki Declaration of 1975. Written informed consent was obtained from all participants.
