The Acquisition of English Morphology by Normal and Educable Mentally Retarded Children

To study the acquisition of English morphology by 30 educable mentally retarded children and 30 normal children, a list of lexicon words was developed which paralleled phonologically and morphologically the nonsense words used by Berko. Results indicate that significant quantitative differences existed favoring the normal children in all the measures of morphology, measured by lexicon words and nonsense words. Nevertheless, the order of acquisition of morphology by the retarded children, particularly in respect to nonsense words, paralleled that of the normal children. With the normal and retarded children an undefined time lag existed between the production of correct English morphological inflection forms with familiar words and the generalization of these forms to unfamiliar words, indicating knowledge of a morphological rule. The retarded children demonstrated greater inability than the normal children studied in generalization from familiar to unfamiliar words.