Improving the visual discrimination of mentally retarded children: a training strategy.

Mentally retarded children were asked to judge whether a series of visual stimuli matched a standard. With each judgment the investigator verbalized "right" or "wrong" and then provided full feedback of particulars, indicating with gesture and words the cue similarities and differences that supported each correct and each incorrect judgment. Control subjects were either given no training (test--retest only) or were asked to make the judgments but given no feedback. Attesting to the efficacy of the training procedure, the trained subjects exhibited total intradimensional transfer; the control subjects, none. The results were related to the attention-retention theory of discrimination learning developed by Fisher and Zeaman and to the "differentiation" methodology and theory presented by Gibson and Gibson.