Executive Dysfunction in Klinefelter Syndrome: Associations With Brain Activation and Testicular Failure.

Context: Executive dysfunction is a well-recognized component of the cognitive phenotype of Klinefelter syndrome (KS), yet the neural basis of KS-associated cognitive weaknesses, and their association with testicular failure is unknown.

Objective: We investigated executive function, brain activation, and pubertal development in adolescents with and without KS.

Methods: Forty-three adolescents with KS (mean age 12.

Adolescent brain development in girls with Turner syndrome.

Turner syndrome (TS) is a common sex chromosome aneuploidy in females associated with various physical, cognitive, and socio-emotional phenotypes. However, few studies have examined TS-associated alterations in the development of cortical gray matter volume and the two components that comprise this measure-surface area and thickness. Moreover, the longitudinal direct (i.