TY - JOUR
T1 - Neural Activation during Mental Rotation in Complete Androgen Insensitivity Syndrome
T2 - The Influence of Sex Hormones and Sex Chromosomes
AU - van Hemmen, Judy
AU - Veltman, Dick J.
AU - Hoekzema, Elseline
AU - Cohen-Kettenis, Peggy T.
AU - Dessens, Arianne B.
AU - Bakker, Julie
PY - 2016/3/1
Y1 - 2016/3/1
N2 - Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a 46,XY karyotype but a female phenotype due to a complete androgen resistance, enable us to study the separate effects of gonadal hormones versus sex chromosomes on neural sex differences. Therefore, in the present study, we compared 46,XY men (n = 30) and 46,XX women (n = 29) to 46,XY individuals with CAIS (n = 21) on a mental rotation task using functional magnetic resonance imaging. Previously reported sex differences in neural activation during mental rotation were replicated in the control groups, with control men showing more activation in the inferior parietal lobe than control women. Individuals with CAIS showed a female-like neural activation pattern in the parietal lobe, indicating feminization of the brain in CAIS. Furthermore, this first neuroimaging study in individuals with CAIS provides evidence that sex differences in regional brain function during mental rotation are most likely not directly driven by genetic sex, but rather reflect gonadal hormone exposure.
AB - Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a 46,XY karyotype but a female phenotype due to a complete androgen resistance, enable us to study the separate effects of gonadal hormones versus sex chromosomes on neural sex differences. Therefore, in the present study, we compared 46,XY men (n = 30) and 46,XX women (n = 29) to 46,XY individuals with CAIS (n = 21) on a mental rotation task using functional magnetic resonance imaging. Previously reported sex differences in neural activation during mental rotation were replicated in the control groups, with control men showing more activation in the inferior parietal lobe than control women. Individuals with CAIS showed a female-like neural activation pattern in the parietal lobe, indicating feminization of the brain in CAIS. Furthermore, this first neuroimaging study in individuals with CAIS provides evidence that sex differences in regional brain function during mental rotation are most likely not directly driven by genetic sex, but rather reflect gonadal hormone exposure.
KW - CAIS
KW - fMRI
KW - sexual differentiation
KW - spatial cognition
KW - testosterone
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84961282076&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/25452569
U2 - https://doi.org/10.1093/cercor/bhu280
DO - https://doi.org/10.1093/cercor/bhu280
M3 - Article
C2 - 25452569
SN - 1047-3211
VL - 26
SP - 1036
EP - 1045
JO - Cerebral cortex (New York, N.Y.
JF - Cerebral cortex (New York, N.Y.
IS - 3
ER -