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Williams syndrome is caused by a microdeletion of ~25 genes on chromosome 7q11.23. Individuals with this syndrome have mild to moderate intellectual disability or learning disabilities. Medical problems typically include heart disease (especially supravalvar aortic stenosis), connective tissue abnormalities, growth deficiency, and ADHD. Williams syndrome is associated with a characteristic cognitive profile including relative strengths in verbal short-term memory and language (especially concrete vocabulary) and extreme weakness in visuospatial construction. Williams syndrome also is associated with a characteristic personality profile including overfriendliness, gregariousness, and empathy, with an undercurrent of worry and anxiety. The first part of my talk focuses on the patterns of language and cognitive abilities in children with Williams syndrome, with an emphasis on the variability associated with the syndrome. To illustrate the relative strengths and weaknesses within the language domain and relations between language and cognitive abilities for children with Williams syndrome, the contrast between relatively good concrete vocabulary and very limited conceptual/relational vocabulary and the relation between conceptual/relational vocabulary and visuospatial constructive ability will be stressed. Pragmatic difficulties associated with Williams syndrome also will be discussed.
Although duplication of the Williams syndrome region should in principle be as common as deletion, the first case of a duplication was published in late 2005, by my research group. Since then, a few other cases have been reported in the literature and my research group has studied a second child of the same age as the first reported case. In marked contrast to deletion of 7q11.23 (Williams syndrome), duplication of 7q11.23 is associated with severe expressive speech and language delay. In the second part of my talk I will compare the language abilities of the two children with duplications whom we have studied to those of similar-CA children with Williams syndrome. I also will contrast the two children with duplications. Both children had similar early speech and language profiles but at 8½ years evidenced strikingly different speech and expressive language abilities even though their IQs were similar. The impact of early and continued speech/language intervention on linguistic outcomes for children with 7q11.23 duplications will be discussed.
Grant funding: NICHD grant# R37 HD29957, NINDS grant# R01 NS35102 |
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