Article

Turner syndrome: Neuroimaging findings: Structural and functional

Department of Psychiatry, Research and Education Centre, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland.
Developmental Disabilities Research Reviews (Impact Factor: 2.75). 01/2009; 15(4):279-83. DOI: 10.1002/ddrr.87
Source: PubMed

ABSTRACT

Neuroimaging studies of Turner syndrome can advance our understanding of the X chromosome in brain development, and the modulatory influence of endocrine factors. There is increasing evidence from neuroimaging studies that TX individuals have significant differences in the anatomy, function, and metabolism of a number of brain regions; including the parietal lobe; cerebellum, amygdala, hippocampus; and basal ganglia; and perhaps differences in "connectivity" between frontal and parieto-occipital regions. Finally, there is preliminary evidence that genomic imprinting, sex hormones and growth hormone have significant modulatory effects on brain maturation in TS.

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    • "TS patients naturally lose one of their 2 normal X chromosomes; therefore, these individuals serve as a valuable human " knockout model " for studying how the X chromosome affects the human brain and cognition. A number of MRI studies have been conducted on TS patients, but they have primarily focused on structural brain anomalies or functional changes during specific cognitive tasks (Mullaney and Murphy 2009 "
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