Pilot study of functional near-infrared spectroscopy of cortical brain function during an auditory and visual N-back task in Klinefelter syndrome

47,XXY (Klinefelter syndrome) is a sex chromosomal aneuploidy, occurring in approximately 1:660 live male births, that results in an extra X chromosome. Most notably, the neurodevelopmental presentation of 47,XXY is associated with deficits in speech and language processing, motor delays, and reading disorders, with language processing and neurodevelopmental impairments. Previous literature has reported structural brain differences in individuals with 47,XXY. Specifically, thinner cortex structure in the temporal and frontal lobes has been reported, including decreased caudate volumes, typically believed to be the origin of speech and language dysfunction associated with this disorder.