Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
Cereb Cortex. 2020 Nov 3;30(12):6152-6168. doi: 10.1093/cercor/bhaa170.
Human white matter development in the first years of life is rapid, setting the foundation for later development. Microstructural properties of white matter are linked to many behavioral and psychiatric outcomes; however, little is known about when in development individual differences in white matter microstructure are established. The aim of the current study is to characterize longitudinal development of white matter microstructure from birth through 6 years to determine when in development individual differences are established. Two hundred and twenty-four children underwent diffusion-weighted imaging after birth and at 1, 2, 4, and 6 years. Diffusion tensor imaging data were computed for 20 white matter tracts (9 left-right corresponding tracts and 2 commissural tracts), with tract-based measures of fractional anisotropy and axial and radial diffusivity. Microstructural maturation between birth and 1 year are much greater than subsequent changes. Further, by 1 year, individual differences in tract average values are consistently predictive of the respective 6-year values, explaining, on average, 40% of the variance in 6-year microstructure. Results provide further evidence of the importance of the first year of life with regard to white matter development, with potential implications for informing early intervention efforts that target specific sensitive periods.
人类大脑白质在生命的最初几年中发育迅速，为后期发展奠定了基础。白质的微观结构特性与许多行为和精神科结果相关；然而，对于白质微观结构的个体差异在何时开始发展，人们知之甚少。本研究旨在描述从出生到 6 岁的白质微观结构的纵向发育情况，以确定个体差异在何时开始出现。224 名儿童在出生后和 1、2、4 和 6 岁时接受了弥散加权成像检查。对 20 条白质束（9 条左右对称束和 2 条连合束）进行了弥散张量成像数据计算，得到了各向异性分数和轴向及径向扩散系数的束内测量值。出生到 1 岁之间的微观结构成熟度变化大于随后的变化。此外，到 1 岁时，各向异性分数和轴向及径向扩散系数的束内平均值的个体差异可以持续预测相应的 6 岁值，平均解释了 6 岁微观结构 40%的变异。研究结果进一步证明了生命第一年对于白质发育的重要性，这可能为针对特定敏感时期的早期干预措施提供信息。
