Harold W. Stevenson
During the past decade there has been a rapid growth of interest in studying the learning processes of retarded individuals. A great deal of this interest has centered on discrimination learning. Although other types of problems have been investigated, there are many reasons why discrimination learning has been so frequently selected for study.
When psychologists move into a relatively unexplored area of research, such as learning in retarded individuals, it is not surprising that they should begin by utilizing problems and methods that have already been developed with other types of subjects. The processes involved in learning to discriminate among stimuli and in transferring such discriminations to successive problems have been popular topics for research, primarily with lower animals. Methods have been developed which make it possible for the experimenter to approach the study of retarded individuals with a degree of methodological sophistication that is not available for other areas of learning, such as classroom learning, skill learning, or language learning. Further, the body of data concerning the performance of lower animals and normal children provides a comparative basis for assessing the performance of retarded individuals. Another reason for selecting discrimination problems is that they are relatively simple, and more nearly adequate control over the experimental situation is possible than if more complex problems are used. Finally, theoretical positions have been developed regarding discrimination learning which provide a framework for interpreting the performance of retarded individuals. Regardless of whether such interpretation is valid, these theories offer an organized means of looking at problems which have guided investigators in selecting variables