In recent years there has been increased concern with the functional significance of "mental imagery" in learning and memory. Prior to the advent of Behaviorism, mental imagery played a major role in the interpretation of such phenomena. However, the revolution in psychology which accompanied the acceptance of Behaviorism resulted in the banishment of imagery, attention, states of consciousness, and other "mentalistic" concepts. Although many factors were probably responsible for the recent reexamination of many of these areas, an altered philosophical climate was certainly important.