title: Analysis of cerebral shape in Williams syndrome.
abstract: BACKGROUND
  As a neurobehavioral disorder with a specific neurocognitive profile and a well-defined genetic etiology, Williams syndrome (WMS) provides an exceptional opportunity to examine associations among measures of behavior, neuroanatomy, and genetics. This study was designed to determine how cerebral shape differs between the brains of subjects with WMS and those of normal controls.
  
  
  METHODS
  Twenty adults with clinically and genetically diagnosed WMS (mean +/- SD age, 28.5 +/- 8.3 years) and 20 healthy, age- and sex-matched controls (mean +/- SD age, 28.5 +/- 8.2 years).
  
  
  METHODS
  High-resolution structural magnetic resonance imaging data were used for shape-based morphological analysis of the right and left cerebral hemispheres and the corpus callosum. Statistical analyses were performed to examine group differences.
  
  
  RESULTS
  Both right and left cerebral hemispheres of subjects with WMS bend to a lesser degree in the sagittal plane than normal controls (P<.001). The corpus callosum also bends less in subjects with WMS (P =.05). In addition, subjects with WMS have decreased cerebral (P<.001) and corpus callosum (P<.001) midline lengths.
  
  
  CONCLUSIONS
  Subjects with WMS have significantly different cerebral shape from normal controls, perhaps due to decreased parieto-occipital lobe volumes relative to frontal regions. The similar observation in the corpus callosum may be associated with a decreased size of the splenium in WMS. These findings may provide important clues to the effect of genes in the WMS-deleted region on brain development.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Rd, Stanford, CA 94305-5719, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Schmitt
authors.forename: S
authors.initials: S
authors.lastname: Eliez
authors.forename: U
authors.initials: U
authors.lastname: Bellugi
authors.forename: A L
authors.initials: AL
authors.lastname: Reiss
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D003337:Corpus Callosum / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D013687:Telencephalon / Q000473:pathology*; D018980:Williams Syndrome / Q000473:pathology*