Aebersold H, Creutzfeldt O D, Kuhnt U, Sanides D
Exp Brain Res. 1981;42(2):127-45. doi: 10.1007/BF00236900.
The fibre arrangement in the optic chiasma (OC) and tract (OT) was investigated with anatomical and physiological methods. In silver impregnated material, principal fibre streams can be demonstrated. In the OC, fibre bundles from each eye cross in a regular basket weave pattern, but deviations of single fibres from the predominant stream are often seen. In the OT, fibres run essentially parallel, and crossings of individual fibres are mainly restricted to the periphery of the tract, or around capillaries. Fibres in the upper segment of the OT are of thin, in the lower segments of thick diameter. Individual fibres labelled by HRP injected in the lateral geniculate body (LGB) run essentially parallel over long distances. Ventromedially to the LGB, bifurcations are found with one branch entering the LGB, the other continuing. 57% of OT-fibres had a receptive field (RF) in the contralateral, 43% in the homolateral eye; 60% in the lower, 40% in the upper visual field; and 6% had a RF in the homolateral visual field, mostly near the vertical meridian. Fibres from the central area were underrepresented in our sample. Fibres from the two eyes were mixed. The RFs of consecutively recorded fibres showed a systematic progression only exceptionally. After plotting RFs of a single penetration on a transformed isodensity ganglion cell map of the visual field, the RF's were distributed along elongated paths on this map. In the OT, such paths ran parallel or slightly inclined relative to the horizontal meridian. They were restricted to either the upper or the lower quadrant or to a path along the horizontal meridian. In the OC, the RF-paths mostly crossed the horizontal meridian at an obtuse angle (average 70 degrees). Thus, the visual field representation rotates by nearly 90 degrees from the OC to the OT. In the OC, the central area is located anteriorly, in the OT dorsally, with the upper visual quadrant laterally and the lower medially. Fibres from the two eyes were mixed and, within the range of the scatter, RFs from the homo- and contralateral eye were in register. It is concluded, that the distribution of fibres in the OC and the OT show a basic retinotopic organization superimposed by scatter.
采用解剖学和生理学方法研究了视交叉（OC）和视束（OT）中的纤维排列。在银浸染材料中，可以显示主要的纤维束。在视交叉中，来自每只眼睛的纤维束以规则的篮状编织模式交叉，但经常可以看到单根纤维偏离主要纤维束。在视束中，纤维基本上平行排列，单根纤维的交叉主要局限于视束的周边或毛细血管周围。视束上段的纤维较细，下段的纤维较粗。注入外侧膝状体（LGB）的辣根过氧化物酶（HRP）标记的单根纤维在很长距离内基本上平行排列。在LGB的腹内侧，发现有分支，一个分支进入LGB，另一个分支继续延伸。57%的视束纤维在对侧眼有感受野（RF），43%在同侧眼有感受野；60%在下部视野，40%在上部视野；6%在同侧视野有感受野，大多靠近垂直子午线。来自中央区域的纤维在我们的样本中代表性不足。来自双眼的纤维混合在一起。连续记录的纤维的感受野仅在极少数情况下显示出系统性进展。在将单次穿刺的感受野绘制在视野的转换等密度神经节细胞图上后，感受野沿该图上的细长路径分布。在视束中，这些路径相对于水平子午线平行或略有倾斜。它们局限于上象限或下象限，或沿着水平子午线的路径。在视交叉中，感受野路径大多以钝角（平均70度）穿过水平子午线。因此，视野表征从视交叉到视束旋转了近90度。在视交叉中，中央区域位于前方，在视束中位于背侧，上部视野象限在外侧，下部视野象限在内侧。来自双眼的纤维混合在一起，在离散范围内，同侧眼和对侧眼的感受野是对齐的。得出的结论是，视交叉和视束中纤维的分布显示出一种基本的视网膜拓扑组织，并叠加有离散。
