ABSTRACT

The developmental origins of handedness remain elusive, though very early emergence suggests individual differences manifesting in utero could play an important role. Prenatal testosterone and Vitamin D exposure are considered, yet findings and interpretations remain equivocal. We examined n = 767 offspring from a population-based pregnancy cohort (The Raine Study) for whom early biological data and childhood/adolescent handedness data were available. We tested whether 18-week maternal circulatory Vitamin D (25[OH]D), and testosterone and estradiol from umbilical cord blood sampled at birth predicted variance in direction of hand preference (right/left), along with right- and left-hand speed, and the strength and direction of relative hand skill as measured by a finger-tapping task completed at 10 (Y10) and/or 16 (Y16) years. Although higher concentrations of Vitamin D predicted more leftward and less lateralized (regardless of direction) relative hand skill profiles, taken as a whole, statistically significant findings typically did not replicate across time-point (Y10/Y16) or sex (male/female) and were rarely detected across different (bivariate/multivariate) levels of analysis. Considering the number of statistical tests and generally inconsistent findings, our results suggest that perinatal testosterone and estradiol contribute minimally, if at all, to subsequent variance in handedness. Vitamin D, however, may be of interest in future studies.

摘要

惯用手的发育起源仍然难以捉摸，尽管很早就出现表明在子宫内表现出个体差异能发挥重要作用。考虑了产前睾酮和维生素 D 暴露，但发现和解释仍然模棱两可。我们检查了 n = 767 个来自基于人群的妊娠队列（雷恩研究）的后代，他们的早期生物学数据和儿童/青春期用手习惯数据可用。我们测试了 18 周的母体循环维生素 D (25[OH]D) 以及出生时采集的脐带血中的睾酮和雌二醇是否预测了手偏好方向（右/左）以及右手和左手方向的差异速度，以及通过在 10 (Y10) 和/或 16 (Y16) 岁时完成的手指敲击任务测量的相关手部技能的强度和方向。尽管较高浓度的维生素 D 预示着相对的手部技能特征会更向左和更少侧化（无论方向如何），作为一个整体，具有统计学意义的发现通常不会跨时间点 (Y10/Y16) 或性别（男性/女性）复制，并且很少在不同（双变量/多变量）分析水平上检测到。考虑到统计测试的数量和普遍不一致的发现，我们的结果表明，围产期睾酮和雌二醇对随后的用手习惯差异的贡献很小，如果有的话。然而，维生素 D 可能对未来的研究感兴趣。如果有的话，随后的惯用方差。然而，维生素 D 可能对未来的研究感兴趣。如果有的话，随后的惯用方差。然而，维生素 D 可能对未来的研究感兴趣。