Enhancement of 4-year-old children's memory span for phonologically similar and dissimilar word lists.

Previous research suggests that preschool children are deficient in rehearsal and that stimulus list repetitions can improve their recall, presumably by substituting for the products of rehearsal. However, the previous research included interitem or postlist retention intervals of several seconds or more. We examined the utility of list repetitions with reference to an ordinary span task in which spoken words were presented 1 s apart for immediate recall.

Disc vascularity in Down's syndrome.

Ocular fundus photographs of 100 eyes were obtained from an institutionalized population of patients with Down's Syndrome (66 males, 34 females). The vascularity of the optic nerve head was assessed in each photograph by counting the number of arterioles, venules, and fine vessels crossing the disc margin. The results of this analysis were compared to similar data obtained from 100 ocular fundus photographs of normal patients and show that there are more large vessels crossing the disc margin in those with Down's Syndrome.