Torrealba F, Guillery R W, Eysel U, Polley E H, Mason C A
J Comp Neurol. 1982 Nov 10;211(4):377-96. doi: 10.1002/cne.902110405.
The manner in which each retina can be mapped onto a single cross section of the optic tract of the cat has been defined by neuroanatomical methods. It has been found that the contralateral nasal hemi-retina and both temporal hemi-retinae are represented in each tract by multiple, rough maps which partially overlap one another. All maps show the same general orientation, with area centralis represented dorsomedially, lower retina represented dorsolaterally, and upper retina represented ventromedially. The peripheral part of the horizontal meridian is represented ventrolaterally. Labeling all of the fibers from one eye by axonal degeneration or autoradiographic methods shows that the crossed map is displaced dorsally and medially relative to the uncrossed map, leaving a dorsomedial crescent of pure crossed fibers. Localized retinal lesions or injections of 3H-amino acid show the general orientation of the maps. Lesions within the dorsomedial pure crossed crescent show that fibers in this crescent arise from retinal areas close to the optic disc, near the site of the early fetal fissure. Localized injections of horseradish peroxidase into the optic tract show the relationships of the several maps in terms of the retinal distribution of retrogradely labeled retinal ganglion cells. They show that axons of large and small cells map ventrolaterally in the tract while intermediate sizes map dorsomedially. They confirm that the crossed map is displaced relative to the uncrossed maps. It is suggested that the optic tract develops by fibers taking a position in the tract in accordance with their time of arrival at the chiasm. The several maps are displaced because they develop sequentially and the optic tract can be read as a developmental record, the most dorsomedial axons being the oldest.
通过神经解剖学方法已明确了猫的每个视网膜映射到视束单个横截面上的方式。研究发现，对侧鼻侧半视网膜和双侧颞侧半视网膜在每条视束中由多个部分相互重叠的粗略图谱表示。所有图谱显示相同的大致方向，中央凹位于背内侧，下部视网膜位于背外侧，上部视网膜位于腹内侧。水平子午线的周边部分位于腹外侧。通过轴突退变或放射自显影方法标记一只眼睛的所有纤维表明，交叉图谱相对于未交叉图谱向背侧和内侧移位，留下一个背内侧的纯交叉纤维新月形区域。局部视网膜损伤或注射³H - 氨基酸显示了图谱的大致方向。背内侧纯交叉新月形区域内的损伤表明，该新月形区域的纤维起源于靠近视盘的视网膜区域，即早期胎儿裂隙的部位附近。向视束局部注射辣根过氧化物酶显示了几个图谱在逆行标记的视网膜神经节细胞视网膜分布方面的关系。结果表明，大细胞和小细胞的轴突在视束中映射到腹外侧，而中等大小的细胞轴突映射到背内侧。这些结果证实了交叉图谱相对于未交叉图谱发生了移位。有人提出，视束是由纤维根据它们到达视交叉的时间在视束中占据一个位置而发育形成的。几个图谱发生移位是因为它们是依次发育的，视束可以被视为一份发育记录，最背内侧的轴突是最古老的。
