Criticism of the DSM-V risk syndrome: A rebuttal

Short-term memory for verbal and visuospatial information was examined in a group of children and teenagers with Down’s syndrome. Performance on the verbal task was impaired relative to matched control groups, but there were no group differences on the visuospatial task. Relatedly, the Down’s syndrome group showed inferior short-term memory for verbal as opposed to visuospatial information, whereas controls showed the opposite pattern. These findings did not appear to result from a general superiority of nonverbal abilities in the Down’s syndrome group, or from hearing difficulties that might have impacted on the verbal short-term memory task, in which material was presented auditorily. The results are consistent with the suggestion that Down’s syndrome is associated with a selective impairment of the phonological loop component of Baddeley and Hitch’s (1974) working memory model.