The major goal of the proposed research is to examine the neurobiological correlates of visuospatial processing deficits in Turner syndrome (TS) using functional magnetic resonance imaging (fMRI). TS is a neurodevelopmental syndrome with a homogeneous etiology, and provides a model for the study of brain-behavior relationships. Recent studies have suggested that individuals with TS show significant deficits in visuospatial information processing but not verbal information processing. Furthermore, these domain-specific visuospatial information processing deficits may be secondary to more central working memory problems in this syndrome. Although the cognitive deficits have been well documented to date, the neural circuitry underlying these deficits have not been characterized. Specifically, there have been no published fMRI studies of TS. In the current project the investigators will use fMRI to examine the neural circuits underlying visuospatial impairments in subjects with TS, with a particular focus on working memory. This project capitalizes on the availability of a large sample of individuals with TS, and the expertise of the investigators in conducting fMRI studies.
Specific Aim 1 is to use functional magnetic resonance imaging to identify the cortical circuits activated by verbal and nonverbal working memory. The investigators will image 15 control subjects and 15 individuals with TS using a modified version of the working memory tasks developed by Belger et al.
Specific Aim 2 is to characterize the neurocognitive functioning of the individuals with this disorder, in particular to explore the hypothesis of domain-specific deficits.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Small Research Grants (R03)
Project #
5R03HD040249-02
Application #
6621621
Study Section
Special Emphasis Panel (ZHD1-MRG-C (BA))
Program Officer
Freund, Lisa S
Project Start
2002-02-15
Project End
2004-01-31
Budget Start
2003-02-01
Budget End
2004-01-31
Support Year
2
Fiscal Year
2003
Total Cost
$72,750
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Psychiatry
Type
Schools of Medicine
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Hart, Sarah J; Davenport, Marsha L; Hooper, Stephen R et al. (2006) Visuospatial executive function in Turner syndrome: functional MRI and neurocognitive findings. Brain 129:1125-36