Demeter S, Ringo J L, Doty R W
Center for Brain Research, University of Rochester School of Medicine, New York 14642.
Hum Neurobiol. 1988;6(4):219-26.
The cross-sectional areas of the corpus callosum (CC) and anterior commissure (AC) were determined by computer-assisted morphometry in normal human brains obtained at autopsy. In addition, the shape of each CC was examined qualitatively by three "blind" observers. A two-fold variation was observed in the cross-sectional area of the CC. Surprisingly, callosal cross-sectional area was not significantly related to brain weight. Moreover, contrary to recent reports, neither simple inspection nor morphometry revealed structural variation related to sex. A striking, seven-fold, variation was observed in the cross-sectional area of the AC. However, AC cross-sectional area was not related either to brain weight or CC cross-sectional area. A trend toward sexual dimorphism in AC cross-sectional area was observed, with males having the larger AC's. Since the interhemispheric commissures are composed, to a large extent, of fibers that link the various cortical areas of the two hemispheres, these observations suggest that variation in the cross-sectional area of the interhemispheric commissures is not simply related to brain weight or sex but, rather, reflects a similar degree of variation in some aspect of cortical structure.
通过计算机辅助形态测量法，测定了取自尸检正常人类大脑的胼胝体（CC）和前连合（AC）的横截面积。此外，由三名“盲法”观察者对每个CC的形状进行了定性检查。观察到CC横截面积存在两倍的差异。令人惊讶的是，胼胝体横截面积与脑重量并无显著关联。此外，与近期报道相反，无论是简单检查还是形态测量都未发现与性别相关的结构差异。观察到AC横截面积存在显著的七倍差异。然而，AC横截面积与脑重量或CC横截面积均无关联。观察到AC横截面积存在性二态性趋势，男性的AC较大。由于半球间连合在很大程度上由连接两个半球不同皮质区域的纤维组成，这些观察结果表明，半球间连合横截面积的差异并非简单地与脑重量或性别相关，而是反映了皮质结构某些方面类似程度的差异。
