Jahanshad Neda, Lee Agatha D, Lepore Natasha, Chou Yi-Yu, Brun Caroline, Barysheva Marina, Toga Arthur W, McMahon Katie L, de Zubicaray Greig I, Wright Margaret J, Sapiro Guillermo, Lenglet Christophe, Thompson Paul M
Laboratory of Neuro Imaging, Dept. of Neurology, UCLA School of Medicine, Los Angeles, CA, USA.
University of Queensland, Functional MRI Laboratory, Centre for MR, Brisbane, Australia.
Proc IEEE Int Symp Biomed Imaging. 2009 Jun-Jul;2009:819-822. doi: 10.1109/ISBI.2009.5193175. Epub 2009 Aug 7.
Studies of cerebral asymmetry can open doors to understanding the functional specialization of each brain hemisphere, and how this is altered in disease. Here we examined hemispheric asymmetries in fiber architecture using diffusion tensor imaging (DTI) in 100 subjects, using high-dimensional fluid warping to disentangle shape differences from measures sensitive to myelination. Confounding effects of purely structural asymmetries were reduced by using co-registered structural images to fluidly warp 3D maps of fiber characteristics (fractional and geodesic anisotropy) to a structurally symmetric minimal deformation template (MDT). We performed a quantitative genetic analysis on 100 subjects to determine whether the sources of the remaining signal asymmetries were primarily genetic or environmental. A twin design was used to identify the heritable features of fiber asymmetry in various regions of interest, to further assist in the discovery of genes influencing brain micro-architecture and brain lateralization. Genetic influences and left/right asymmetries were detected in the fiber architecture of the frontal lobes, with minor differences depending on the choice of registration template.
对大脑不对称性的研究能够为理解每个脑半球的功能特化以及疾病状态下这种特化如何改变打开大门。在此，我们使用扩散张量成像（DTI）对100名受试者的纤维结构中的半球不对称性进行了研究，采用高维流体配准来将形状差异与对髓鞘形成敏感的测量指标区分开来。通过使用共同配准的结构图像将纤维特征（分数各向异性和测地线各向异性）的三维图谱流体配准到结构对称的最小变形模板（MDT），减少了纯结构不对称性的混杂效应。我们对100名受试者进行了定量遗传分析，以确定剩余信号不对称性的来源主要是遗传的还是环境的。采用双生子设计来识别感兴趣的各个区域中纤维不对称性的可遗传特征，以进一步协助发现影响脑微结构和脑侧化的基因。在前额叶的纤维结构中检测到了遗传影响和左右不对称性，根据配准模板的选择略有差异。
