Rattus norvegicus var. albinus (Neobehaviorism)

1929

Clark Hull (1884–1952), Edward Chase Tolman (1886–1959)

The behavior under controlled laboratory conditions of the small albino rodent Rattus norvegicus var. albinus (Norway rat) became the primary object of study for mainstream American psychology between the two world wars. Using the Darwinian principle of the continuity of species, psychologists argued that nonhuman animals could be used as stand-ins for humans in studies about learning. In the laboratory, the conditions of learning could be experimentally manipulated, and the laws of learning could be discovered; the white rat became the analog of choice to realize these laws. The dominance of this approach within scientific psychology led one historian to call it the “kingdom of behavior.” In 1913, psychologist John B. Watson prepared the way for the kingdom in his behaviorist manifesto: “Psychology as the behaviorist views it is a purely experimental branch of natural science. Its theoretical goal is the prediction and control of behavior.”

Two psychologists who exemplified the many variants of behaviorism, pioneering an approach that came to be called neobehaviorism, were Clark Hull and Edward Chase Tolman. At Yale, where he became a professor in 1929, Hull was described as the American Pavlov, who “uses Yale sophomores instead of dogs.” He adopted a conditioned reflex model from the work of Ivan Pavlov to study alcoholism, psychoses, juvenile delinquency, and bullying. His graduate students followed his lead and successfully used conditional reflex theory and Psychoanalysis to study human frustration and its links to aggression in such problems as labor strife and racial conflict.

On the other coast, at the University of California, Berkeley, Tolman rejected Hull’s claim that learning consists of chains of conditioned reflexes. Learning, Tolman argued, can be separated from performance. The rat learns about the maze even without reinforcement, as demonstrated the moment a food reward is introduced and the rat goes to it immediately, which Tolman called latent learning. Tolman interpreted this as supportive of his theory that learning is goal directed.

SEE ALSO Classical Conditioning (1903), Behaviorism (1913), Operant Chamber (1930), Teaching Machine (1954)

Rat from the Wistar Institute—the first to breed pure lines of animals for use in laboratory experiments. The white Norway rat quickly became the favorite of psychologists.