ABSTRACT
THE last decade has witnessed an increased scientific interest in the learning, or more properly, the learning deficiencies of mental retardates. McPherson in 1948 was able to list only a dozen studies devoted to a consideration of learning in mentally defective individuals. Since then a steady stream of research has been making its way into the literature. Almost every area and aspect of learning has been touched. Furthermore, attempts have been made to develop theories applicable to the learning deficits characteristic of defective individuals (e.g., Ellis, 1963; Zeaman and House, 1963).
