Neurofunctional Differences Associated with Arithmetic Processing in Turner Syndrome

• Published in: Cerebral cortex (New York, N.Y. 1991) Vol. 16; no. 6; pp. 849 - 856
• Main Authors: Kesler, Shelli R., Menon, Vinod, Reiss, Allan L.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.06.2006; Oxford Publishing Limited (England)
• Subjects: arithmetic processing; fronto-parietal regions; neurofunctional differences; Turner Syndrome
• ISSN: 1047-3211; 1460-2199
• DOI: 10.1093/cercor/bhj028

Turner syndrome (TS) is a neurogenetic disorder characterized by the absence of one X chromosome in a phenotypic female. Individuals with TS are at risk for impairments in mathematics. We investigated the neural mechanisms underlying arithmetic processing in TS. Fifteen subjects with TS and 15 age-matched typically developing controls were scanned using functional MRI while they performed easy (two-operand) and difficult (three-operand) versions of an arithmetic processing task. Both groups activated fronto-parietal regions involved in arithmetic processing during the math tasks. Compared with controls, the TS group recruited additional neural resources in frontal and parietal regions during the easier, two-operand math task. During the more difficult three-operand task, individuals with TS demonstrated significantly less activation in frontal, parietal and subcortical regions than controls. However, the TS group's performance on both math tasks was comparable to controls. Individuals with TS demonstrate activation differences in fronto-parietal areas during arithmetic tasks compared with controls. They must recruit additional brain regions during a relatively easy task and demonstrate a potentially inefficient response to increased task difficulty compared with controls.