Constant D, Ruther H
Department of Anatomy and Cell Biology, University of Cape Town Medical School, Observatory, South Africa.
Brain Res. 1996 Jul 15;727(1-2):99-106. doi: 10.1016/0006-8993(96)00358-7.
Mid-sagittal magnetic resonance images of 104 normal individuals were analyzed to assess whether or not the corpus callosum or parts thereof is sexually dimorphic in favor of females. Subjects were 56 males and 48 females, both groups being closely age matched. The outline of the corpus callosum was divided into seven subareas, using three different orientations. A comparison was made between subareas with the divisions based on different orientations. Results showed significant differences (P < 0.05) in all cases, with one exception in females. No significant sexual dimorphism was found, with the exception of one subarea in one of the orientations which was significantly larger in males. No significant correlation was found between corpus callosal area and either cerebral hemispheric area or an estimate of cranial capacity. Relative measures, incorporating these two brain size indicators as covariates, also showed no significant sexual dimorphism. In conclusion, no sexual dimorphism of the human corpus callosum favoring females was found in this study, and it appears that inadequate sampling, differing feature orientation, and inappropriate size correction procedures may have been factors responsible for conflicting results in previous studies.
对104名正常个体的正中矢状面磁共振图像进行分析，以评估胼胝体或其部分是否存在有利于女性的性别差异。受试者包括56名男性和48名女性，两组年龄密切匹配。胼胝体的轮廓使用三种不同的方向被划分为七个子区域。对基于不同方向划分的子区域进行了比较。结果显示，除女性的一个例外情况外，所有情况下均存在显著差异（P < 0.05）。未发现明显的性别差异，唯一的例外是在一种方向上的一个子区域，男性的该区域明显更大。胼胝体面积与大脑半球面积或颅容量估计值之间未发现显著相关性。将这两个脑大小指标作为协变量纳入的相对测量也未显示出明显的性别差异。总之，本研究未发现人类胼胝体存在有利于女性的性别差异，并且似乎样本不足、特征方向不同以及大小校正程序不当可能是导致先前研究结果相互矛盾的因素。
