한국인 태아 대뇌상두정소엽(Brodmann 제7피질분야)의 세포구축학적 연구

Abstract

The author studied on the development and cytoar• chitectonics of the cerebral cortex in the Brodmann s area of 7 of the 133 (male 69, female 64) Korean fetal brains, and summarized the result as follows; 1. The thickness of the cerebral cortex was very thin of O. 393mm at the fourth month of fetal age and increased very rapidly in the fifth and sixth month. slowly from the seventh to the ninth month , and very rapidly again in the tenth month. As to the relation between brain weight and the thickness of the cerebral cortex, the thickness of the cerebral cortex was very thin under 50gm of brain weight; increased very rapidly until the brain weight gaind to 101-150gm, thereafter increased slowly to 301-350gm and increased very rapidly again over 350gm of brain weight. 2. The dfferentiation of the lamination of the cerebral cortex began a diverge in the sixth fetal month , and the lamination of the cortex occured almost completly at the seventh fetal month. As the relation of the differentiation of the cerebral cortex with the brain weight , it began a diverge from 51gm to 100gm of the brain weight, but there might be an individual difference of lamination. 3. The relative cell density of the cerebral cortex cannot be measured under the fifth month of fetal age , but possibly measured in the sixth month of fetal age. The relative cell density of the corebral cortex was very high in the sixth and the seventh fetal month. and thereafter it decreased gradually as the increase of fetal age. As the relation of the relative cell density with the brain weight. the relative cell density was very high up to 150gm of brain weight. and thereafter it decreased gradually as the increase of the brain weight. The absolute cell density was found the resemblance of the relative cell density. 4. The nerve cells of the fetal' cortex might be increased very rapi d,ly up to the seventh month of fetal age. and thereafter the number of the nerve cells of the cortex might be stabilized. 6. Thickness of the cortex. the relative cell density and absolute cell density of the cerebral cortex had almost no sexual difference.