ABSTRACT
A link between drug action on the one hand and learning theory on the other was adumbrated by C. L. Hull in a pioneer paper on the influence of caffeine on rote learning. Pharmacological effects are usually studied on a purely empirical level. A certain drug is given to a group of subjects, and various tests, chosen more or less at random, are then applied. The prime interest of the student of personality in this field is the fact that drugs are among the few influences which can be brought to bear experimentally on human subjects in an endeavour to change their performance and possibly even to shift their position on one of the personality continua. There are two sets of drugs which have antagonistic effects at both the physiological and the psychological level. Sodium amytal, being a depressant drug, would be postulated to increase inhibition.
