Developmental vs. difference theories of mental retardation: a new look.
Performance of three groups of children (retarded, nonretarded, and language-impaired) on nonlinguistic symbolic and conceptual cognitive tasks was measured. The performance of the retarded and nonretarded groups was essentially similar, while both of these groups generally performed at higher stage levels than did the language-impaired group. Several testable implications were suggested.
D002648:Child; D002657:Child Development; D002675:Child, Preschool; D003072:Cognition Disorders / Q000523:psychology*; D003210:Concept Formation; D004193:Discrimination Learning; D006801:Humans; D008607:Intellectual Disability / Q000523:psychology*; D007805:Language Development Disorders / Q000523:psychology; D010364:Pattern Recognition, Visual; D011582:Psychological Theory; D012858:Size Perception; D013028:Space Perception; D014110:Touch