Luders E, Narr K L, Thompson P M, Woods R P, Rex D E, Jancke L, Steinmetz H, Toga A W
Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, Los Angeles, CA 90095-1769, USA.
Neuroimage. 2005 Jun;26(2):493-501. doi: 10.1016/j.neuroimage.2005.02.010. Epub 2005 Apr 12.
Using magnetic resonance imaging and well-validated computational cortical pattern matching methods in a large and well-matched sample of healthy subjects, we analyzed the effects of gender on regional gray matter (GM) concentration across the cortex. To clarify discrepancies in previous reports, we also examined sexual dimorphisms for whole-brain tissue volumes with and without controlling for brain size differences. In addition, we generated spatially detailed maps of average GM distributions and variability across the entire cortex given that these descriptors are not well characterized in the normative literature. After brain size correction, we detected numerous cortical regions showing significantly increased GM concentration in females compared to males, but no regionally increased GM concentration in males. Permutation testing confirmed the statistical significance of these findings. Locally increased concentration of cortical GM in females corroborates findings of larger global GM volumes in females after correcting for individual brain sizes. Larger global volumes of GM, white matter and CSF, however, are observed in males when individual brain volumes are not taken into account. Our results show that gender is a major contributor to regional and global GM differences between individuals, although the nature of these effects depend on whether brain size is taken into account.
在一大组匹配良好的健康受试者样本中，我们运用磁共振成像以及经过充分验证的计算皮质模式匹配方法，分析了性别对整个皮质区域灰质（GM）浓度的影响。为了厘清先前报告中的差异，我们还在控制和未控制脑大小差异的情况下，研究了全脑组织体积的性别二态性。此外，鉴于这些描述符在规范性文献中并未得到充分表征，我们生成了整个皮质平均GM分布和变异性的空间详细图谱。在进行脑大小校正后，我们检测到许多皮质区域，与男性相比，女性的GM浓度显著增加，但男性没有区域GM浓度增加的情况。置换检验证实了这些发现的统计学意义。在校正个体脑大小后，女性皮质GM局部浓度增加，这与女性总体GM体积较大的发现相一致。然而，在不考虑个体脑体积的情况下，男性的GM、白质和脑脊液总体积更大。我们的结果表明，性别是个体之间区域和总体GM差异的主要影响因素，尽管这些影响的性质取决于是否考虑脑大小。
