Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

Abstract

Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49) responded to whether the words “GREEN” or “RED” were displayed in green or red (incongruent versus congruent colors). One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying “GREEN” or “RED” had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

Klinefelter syndrome comorbidities linked to increased X chromosome gene dosage and altered protein interactome activity

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Sex differences in post-stroke aphasia rates are caused by age. A meta-analysis and database query

“…Speaking against this is the fact that the observed sex difference in aphasia goes directly against the conclusions of the author’s prior work. I have argued against the existence of large sex differences in the brain architecture supporting language, both in review articles [18, 110] and based on neuroimaging studies [109, 111]. Before starting the data collection, I assumed that there would be no differences in aphasia related to sex.…”

Aberrant ocular architecture and function in patients with Klinefelter syndrome

“…Recent publications show anatomical deviations in another part of the central nervous system of KS patients; the brain 26 . No differences in activity of visual cortex have been described 27 . In all groups, retinal thickness increased with decreasing size of FAZ in accordance to a previously published record 28 .…”