ABSTRACT
This chapter presents an historical discussion of the impact of medical X-rays on psychology, with an emphasis on implications for understanding the changed eating behavior and emesis often observed in cancer patients. A considerable body of research has demonstrated that animals do, indeed, demonstrate new learning as a result of undergoing radiation. History has imposed a certain social structure upon medical research with ionizing radiation. Research began within the purview of physics, but with the advent of the X-ray discharge tube medical scientists and practitioners took over. In order to appreciate the theoretical and practical problems created for psychology by the X-ray data, one must keep in mind the rigid associationistic structure of traditional learning theory. The Law of Similarity has played a relatively minor role in learning theory. The most popular belief, at least before the dawn of the atomic age, was that X-ray was not a stimulus.
