Auditory-visual equivalence by mentally retarded and intellectually average older children

Auditory-visual information equivalence in 15 mentally retarded and 15 intellectually average 12- to 13-year-old children were compared using nine matching tasks. Intellectually average subjects were more accurate on both intra- and intersensory tasks. Retarded subjects were more accurate on intra- than on intersensory tasks, whereas there was no such difference for the average subjects. Tasks involving transposition were more difficult for the retarded children than those not involving transposition. The intellectually average children behaved similarly on intrasensory tasks but on intersensory tasks were more accurate when transposition was involved. There was no association between IQ and intra- or intersensory performance when data from the two groups were examined separately.