Behavioral and Brain Functions

Background: Chromosome 22q11.2 deletion syndrome is one of the most common genetic causes of cognitive impairment and developmental disability yet little is known about the neural bases of those challenges. Here we expand upon our previous neurocognitive studies by specifically investigating the hypothesis that changes in neural connectivity relate to cognitive impairment in children with the disorder. Methods: Whole brain analyses of multiple measures computed from diffusion tensor image data acquired from the brains of children with the disorder and typically developing controls. We also correlated diffusion tensor data with performance on a visuospatial cognitive task that taps spatial attention. Results: Analyses revealed four common clusters, in the parietal and frontal lobes, that showed complementary patterns of connectivity in children with the deletion and typical controls. We interpreted these results as indicating differences in connective complexity to adjoining cortical regions that are critical to the cognitive functions in which affected children show impairments. Strong, and similarly opposing patterns of correlations between diffusion values in those clusters and spatial attention performance measures considerably strengthened that interpretation. Conclusion: Our results suggest that atypical development of connective patterns in the brains of children with chromosome 22q11.2 deletion syndrome indicate a neuropathology that is related to the visuospatial cognitive impairments that are commonly found in affected individuals. Background Chromosome 22q11.2 deletion syndrome (22q11.2DS) is caused by a microdeletion within chromosome 22 at band q11.2 [1-3] and encompasses DiGeorge [4], Velocardiofacial [5] and several other syndromes. The phenotypic spectrum of 22q11.2DS includes over 180 physical anomalies, learning disabilities, and psychiatric manifestations [6], only a small subset of which are observed in any Published: 17 June 2008 Behavioral and Brain Functions 2008, 4:25 doi:10.1186/1744-9081-4-25 Received: 12 December 2007 Accepted: 17 June 2008 This article is available from: http://www.behavioralandbrainfunctions.com/content/4/1/25 © 2008 Simon et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.