[Representation and language development of profoundly mentally retarded children]

The relationship between cognitive and language developments of ten profoundly mentally retarded children was examined through a longitudinal study. Cognitive processing tasks with matching-to-sample procedure were employed to examine the perceptual identification and representative function of objects. Concerning the development of language, both periods in which the comprehension and the utterance of object names emerged in each subject were recorded. There was no one-to-one correspondence between the onsets of representative function and language development, i.e. the comprehension of object names emerged not only before, but also a long time after, the onset of representative function. Also, there was little possibility that the utterance of object names emerged simultaneously at the onset of representation.