A negative test of the drive-reduction hypothesis

A major deduction of the drive-reduction hypothesis of reinforcement was tested. A light which follows the termination of a shock coincides with a condition of drive or need reduction. If drive reduction is a sufficient condition for reinforcement, then the light should become a secondary reinforcing agent by virtue of its association with the drive-reduction event. If it becomes a secondary reinforcing agent, it should be able to reinforce an instrumental act.

This sequence of deductions was tested by placing rats in a stock, giving them a brief shock upon the termination of which a light was flashed for one second. After sixty such pairings, subjects were then placed in a Skinner box under operant test conditions; when they pressed the bar a light flashed on.

Animals subjected to this training programme were compared for rate of bar pressing with animals subjected to a variety of control conditions. No significant differences were found among the groups, and it was concluded that in so far as the deductions from drive-reduction theory were correct, the theory was not substantiated. The paper concludes with a discussion of various problems which might limit the interpretation of the experimental results.