Reese B E, Cowey A
University of Oxford, Department of Human Anatomy,UK.
Nature. 1988 Jan 28;331(6154):350-1. doi: 10.1038/331350a0.
The classical neuro-ophthalmologic literature describes the organization of the primate's optic tract as containing a single topographic representation of the complete contralateral visual hemifield. In contrast, cats have separate visual field representations for the optic axons of the functionally distinct retinal ganglion cell classes. As the line of decussation for each ganglion cell class in the cat occupies a different location on the retinal surface, whereas in primates they are all superimposed, such a species difference might be expected. We report that implants of horseradish peroxidase placed in either the deep or superficial extremes of the monkey's optic tract produce retrograde labelling of distinct retinal ganglion cell classes, and produce anterograde labelling confined to distinct laminae of the lateral geniculate nucleus. Hence, the optic tract of the primate cannot contain a single representation of the contralateral visual hemifield; rather, independent visual field representations for the functionally distinct optic axons must exist. Their anatomical segregation may account for the clinical observation of selective impairments of distinct visual abilities following partial interruption of the optic tract in man.
经典神经眼科学文献描述灵长类动物的视束组织包含对侧完整视野的单一拓扑表征。相比之下，猫对于功能不同的视网膜神经节细胞类别的视神经轴突具有独立的视野表征。由于猫中每个神经节细胞类别的交叉线在视网膜表面占据不同位置，而在灵长类动物中它们全部重叠，因此可能预期存在这样的物种差异。我们报告，将辣根过氧化物酶植入猴子视束的深部或浅部末端，会产生不同视网膜神经节细胞类别的逆行标记，并产生仅限于外侧膝状体不同层的顺行标记。因此，灵长类动物的视束不可能包含对侧视野的单一表征；相反，功能不同的视神经轴突必须存在独立的视野表征。它们的解剖学分离可能解释了人类视束部分中断后不同视觉能力选择性受损的临床观察结果。
