This study addressed the question of whether there is a specific reaction time deficit in individuals with Down syndrome. To investigate this question, the manual and vocal reaction times of 18 Down syndrome and 2 control groups were compared. One control group consisted of intellectually handicapped children matched on intellectual ability, the other consisted of younger nonhandicapped children also of similar mental age. The results confirmed that a specific RT deficit does indeed exist and is present for both manual and vocal responses.
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