Article

Cognition and lobar morphology in full mutation boys with fragile X syndrome.

Department of Research on Children with Special Needs, Medical Genetics Division, The National Research Centre, Cairo, Egypt.
Brain and Cognition (impact factor: 3.17). 11/2011; 78(1):74-84. DOI:10.1016/j.bandc.2011.09.005
Source: PubMed

ABSTRACT The aims of the present study are twofold: (1) to examine cortical morphology (CM) associated with alterations in cognition in fragile X syndrome (FXS); (2) to characterize the CM profile of FXS versus FXS with an autism diagnosis (FXS+Aut) as a preliminary attempt to further elucidate the behavioral distinctions between the two sub-groups. We used anatomical magnetic resonance imaging surface-based morphometry in 21 male children (FXS N=11 and age [2.27-13.3] matched controls [C] N=10). We found (1) increased whole hemispheric and lobar cortical volume, cortical thickness and cortical complexity bilaterally, yet insignificant changes in hemispheric surface area and gyrification index in FXS compared to C; (2) linear regression analyses revealed significant negative correlations between CM and cognition; (3) significant CM differences between FXS and FXS+Aut associated with their distinctive behavioral phenotypes. These findings are critical in understanding the neuropathophysiology of one of the most common intellectual deficiency syndromes associated with altered cognition as they provide human in vivo information about genetic control of CM and cognition.

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Keywords

alterations
 
anatomical magnetic resonance imaging surface-based morphometry
 
autism diagnosis
 
common intellectual deficiency syndromes
 
cortical complexity bilaterally
 
cortical morphology
 
cortical thickness
 
distinctive behavioral phenotypes
 
elucidate
 
fragile X syndrome
 
hemispheric surface area
 
insignificant changes
 
lobar cortical volume
 
significant negative correlations
 
two sub-groups