Department of Bioengineering, National University of Singapore, Singapore.
Neuroimage. 2013 Jan 15;65:315-23. doi: 10.1016/j.neuroimage.2012.09.032. Epub 2012 Sep 18.
This paper presents the growth pattern and sexual dimorphism of the thalamus and basal ganglia in a large-scale Asian neonatal cohort using both T2-weighted magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Our study observed a robust growth of the thalamus and basal ganglia (caudate, putamen, globus pallidus, and anterior limb of internal capsule) beyond the overall brain growth in the early postnatal period (36-43 weeks of the gestational age). Additionally, the microstructure of the two structures was integrated as reflected by an increase in fractional anisotropy (FA) and a decrease in axial and radial water diffusivities in the first few weeks of life. Sexual dimorphism was only observed in the whole brain growth and the left thalamic volume but not in the other volumes or DTI measures of the basal ganglia and thalamus at birth. Even though the pattern of sexual dimorphism in the total brain volume is present at birth and persists throughout postnatal brain development, sexual dimorphisms of the basal ganglia and thalamus differ from those found in later stages of brain development, indicating that regionally distinct patterns of postnatal brain development between males and females arise after birth.
本文利用 T2 加权磁共振成像(MRI)和弥散张量成像(DTI),在一个大型亚洲新生儿队列中展示了丘脑和基底节的生长模式和性别二态性。我们的研究观察到,在出生后的早期(胎龄 36-43 周),丘脑和基底节(尾状核、壳核、苍白球和内囊前肢)的生长速度明显快于整个大脑。此外,这两个结构的微观结构也有所整合,表现在出生后几周内各向异性分数(FA)增加,轴向和径向水扩散率降低。性别二态性仅在大脑整体生长和左侧丘脑体积中观察到,而在基底节和丘脑的其他体积或 DTI 测量中则没有。尽管在出生时就存在大脑整体体积的性别二态性,并在整个出生后大脑发育过程中持续存在,但基底节和丘脑的性别二态性与后期大脑发育中发现的不同,这表明男女出生后大脑发育的区域性差异模式不同。