Magnitude of reward and acquisition of a black-white discrimination habit.

Abstract

In his Principles of Behavior Hull (3) postulated that the amount of reward had a direct influence upon the asymptote of habit strength. Subsequent research (1, 12) yielded results which did not appear to be in strict conformity with predictions based upon this formulation. Hull (4) then modified his postulate set in order to take better account of these data. The revision states that magnitude of reward is the determinant of motiveincentive conditions (K) which are a constituent of reaction potential (SER), and which have a logical status within the system comparable to drive (D). The present investigation is an attempt to clarify the role of the reward variable in learning situations.The investigations which apparently contributed most to the revised assumptions concerning the magnitude of reward were those of Crespi (1) and Zeaman (12). These two studies have in common the utilization of a running response in a straight alley. Crespi measured running speed, whereas Zeaman measured latencies. The findings of these two studies are similar. In general, the data show differences in the asymptotes of performance as a function of magnitude of reward. This is consistent with Hull's early formulation. However, under conditions of switched rewards two effects were noted: (a) Performance is ir The present study is a portion of a thesis presented to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Doctor of Philosophy. The writer is indebted to Dr. M. P. Smith, who directed the investigation.

Age, sex, and rearing conditions as variables in simple brightness discrimination.

“…The results pertaining to the sex variable are in accord with results incidentally reported by Greene (1953) and with Munn's conclusion (1950, p. 351) that "There is apparently no consistent difference in the learning ability of males and females." The complete ineffectualness of the rearing variable comes as something of a surprise and merits verification over a wider age span.…”

Strength of secondary reinforcement as a determiner of the effects of duration of goal response on learning.

“…The above interpretation implies that any stimulus situation which has 3 It is assumed that magnitude of reward effects result from past learning based on different durations of the goal response following large and small reward. This assumption follows from our analysis and is supported by a minor unpublished study conducted by R. Rehula in the Kent State laboratory.…”

“…Let us now consider how duration of the goal response (e.g., eating) resembles delayed reward. 3 The stimulus situation during successive 10-sec. intervals may be represented by XA\I XAI, etc.…”

The effect of amount of reinforcement on the formation of the reinforcing value of a verbal stimulus.

“…In addition to this general finding, this study represents a systematic replication of the findings concerning the effect of amount of reinforcement with lower organisms. Previously described results of performance varying with the amount of primary reinforcement (Crespi, 1942;Zeaman, 1949;Guttman, 1953;Hutt, 1954) and of the amount of primary reinforcement differentially affecting the value of a conditioned reinforcer (Wolfe, 1936;Greene, 1953;D'Amato, 1955;Butter & Thomas, 1958) are seen in the differential effect of varying amounts of money when directly contingent on behaviour and in the fact that the monetary amount a verbal stimulus is paired with is related to its value as a verbal reinforcer. Also, for the levels measured in this study, the effect of manipulating the two measures of amount, AT and AP, was very similar.…”