Denenberg V H, Berrebi A S, Fitch R H
Biobehavioral Sciences Graduate Degree Program, University of Connecticut, Storrs 06269-4154.
Brain Res. 1989 Sep 18;497(2):271-9. doi: 10.1016/0006-8993(89)90272-2.
Previous work from our laboratory (Berrebi et al., Brain Research, 438 (1988) 216-224) demonstrated region-specific sexual dimorphisms in the size of the rat's corpus callosum, which are modifiable by extra stimulation in early life. These differences are assumed to reflect regional corticocortical fibers of passage which are altered differentially by gender and our experimental manipulations. In this paper, we report our findings when the original data are reanalyzed using a newly developed computer program. This program not only reproduced, with very high accuracy, the original means, but also permitted us to examine computer generated callosal width scores via a factor analysis procedure. Such a procedure yields useful information concerning the clustering of callosal fibers and thus contributes significantly to our hypothesis that discrete cortical regions are selectively sensitive to experimental variables. Factor analyses of the callosal variables and brain weight of 155 rats found 7 width factors, and an eighth factor which contained the variables of brain weight, callosal length, and callosal perimeter. Callosal area did not load significantly on any of these factors. The percentile locations of the width factors, starting at the anterior (genu) end were: widths 1-5, 6-17, 24-38, 46-57, 62-72, 79-95 and 96-99. Use of these factor scores in analyses of variance revealed that the male callosum is wider than the female's, with the differences most pronounced in the genu and the most posterior portion of the splenium. Both age and early handling experience influenced the callosal width factors.(ABSTRACT TRUNCATED AT 250 WORDS)
我们实验室之前的研究（贝雷比等人，《大脑研究》，438（1988）216 - 224）表明，大鼠胼胝体大小存在区域特异性的性别差异，这种差异可通过早期生活中的额外刺激而改变。这些差异被认为反映了通过的区域皮质 - 皮质纤维，其因性别和我们的实验操作而有不同改变。在本文中，我们报告了使用新开发的计算机程序重新分析原始数据时的研究结果。该程序不仅以非常高的准确性重现了原始均值，还使我们能够通过因子分析程序检查计算机生成的胼胝体宽度分数。这样的程序产生了有关胼胝体纤维聚类的有用信息，从而对我们的假设做出了重大贡献，即离散的皮质区域对实验变量具有选择性敏感性。对155只大鼠的胼胝体变量和脑重量进行因子分析，发现了7个宽度因子，以及第8个因子，其中包含脑重量、胼胝体长和胼胝体周长变量。胼胝体面积在这些因子中均无显著载荷。宽度因子的百分位数位置，从胼胝体前部（膝部）开始依次为：宽度1 - 5、6 - 17、24 - 38、46 - 57、62 - 72、79 - 95和96 - 99。在方差分析中使用这些因子分数表明，雄性胼胝体比雌性宽，差异在膝部和压部最末端最为明显。年龄和早期处理经验均影响胼胝体宽度因子。（摘要截断于250字）
