D. below the population average, although the discrepancy between verbal intelligence quotient and performance intelligence quotient was more limited than that described in some previous studies [5], [9] and [14]. Our control group of patients with
spinal muscular atrophy and osteogenesis Vincristine price imperfecta was severely motor impaired but did not exhibit any cognitive deficits, thus confirming that motor impairment does not influence intellectual abilities, as already demonstrated by Billard et al. [10]. Separate analyses taking into account the genetic alterations in the dystrophin gene (Duchenne muscular dystrophy distal and Duchenne muscular dystrophy proximal) indicated that the verbal intelligence quotients in both groups were significantly lower than those of control children, whereas only children in the distally mutated Duchenne muscular dystrophy group showed significantly lower performance intelligence quotients. Patients with distal mutations were generally more severely
affected and manifested different patterns of strengths and impairments, in comparison to patients with proximal mutations. In particular, distal mutations seem to produce greater deficits in verbal short-term memory, as expressed by low Digit Span scores (and possibly working memory, which may also be responsible for the OSI-744 molecular weight low performances in the Picture Arrangement subtest), in visual memory, and in visuospatial organization, as expressed by lower scores on the Performance subtests of the Wechsler Intelligence Scale for Children-Revised, especially in Object Assembly, MRIP and also in logical sequencing
(Picture Arrangement). On the other hand, patients with mutations in the proximal portion of the dystrophin gene demonstrated relative strengths in verbal short-term memory (as measured by the Digit Span subtest) and in the Performance subtests of the Wechsler scales, especially Object Assembly, Mazes, and Picture Arrangement (requiring visuospatial organization and planning), whereas they exhibited some difficulties in social judgment and the critical appreciation of general statements (as measured by the Comprehension subtest). Furthermore, dystrophic children with distal mutations manifested clear difficulties in syntactic processing, as expressed by both Token Test and Grammatical Comprehension scores. Finally, lower scores in Visual Memory were also an exclusive characteristic of patients with distal mutations, whereas deficits in Visual Attention were common to both subgroups. Analyses controlling for the influence of general intellectual deficits on specific linguistic, neuropsychologic, and academic functions revealed that most of the deficits were substantially explained by variations in intelligence quotients.