Sex specific relationships between infants’ mental rotation ability and amiotic sex hormones

• Published in: Neuroscience letters Vol. 707; p. 134298
• Main Authors: Erdmann, Kathrin, Schaal, Nora K., Meinlschmidt, Gunther, Tegethoff, Marion, Fröhlich, Susanne, Kozlowski, Peter, Rivet, Noëllie, Jamey, Carole, Reix, Nathalie, Kintz, Pascal, Raul, Jean-Sébastien, Heil, Martin
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 10.08.2019
• Subjects: Amniocentesis; Amniotic Fluid - chemistry; Attention; Estradiol - analysis; Female; Fixation, Ocular; Humans; Imagination; Infant; Infant cognition; Life Sciences; Male; Mental rotation; Prenatal estradiol; Prenatal testosterone; Recognition, Psychology; Rotation; Sex differences; Sex Factors; Testosterone - analysis; Toxicology; Mental rotation; Amniocentesis; Sex differences; Prenatal estradiol; Prenatal testosterone; Infant cognition
• ISSN: 0304-3940; 1872-7972; 1872-7972
• DOI: 10.1016/j.neulet.2019.134298

•Testosterone and estradiol from amniotic fluid were correlated with infants’ performance on a mental rotation task and an index of vigilance.•For 6-months-old boys (N = 104) mental rotation but not vigilance was correlated with prenatal testosterone but not with estradiol.•For 6-months-old girls (N = 104) mental rotation but not vigilance was correlated with prenatal estradiol but not with testosterone.•In both cases, only about 5% of the within-sex variance in mental rotation performance was due to prenatal sex hormones indicating small effects. Sex differences in mental rotation, robust in adults, have recently been reported for infants’ looking times although the pattern of results is not completely conclusive. In this context, organizational effects of gonadal steroids affecting the neural circuitry underlying spatial cognition could be (partly) responsible for the early sex difference. In the present study testosterone and estradiol levels measured in amniotic fluid via ultra performance liquid chromatography and tandem mass spectrometry were used to examine the role of prenatal sex hormones on infants’ looking times during mental rotation. N = 208 six-month-old infants participated in an expectation of violation task with 3D cube figures. Mental rotation was defined as the difference in looking times for familiar versus mirrored cube figures whereas vigilance was defined as the sum of both looking times. Sex differences were absent for mental rotation as well as for vigilance. Most importantly, however, for boys mental rotation but not vigilance was correlated with prenatal testosterone but not with estradiol. For girls mental rotation but not vigilance was correlated with prenatal estradiol but not with testosterone although it has to be noted that the testosterone values for girls suffered from a floor effect. Only 5% of the within-sex variance was due to prenatal sex hormones indicating small effects. These findings extend our knowledge concerning organizational effects of prenatal sex hormones on the brain circuitry underlying spatial cognition.