Keating E G, Horel J A
Brain Res. 1976 Jan 16;101(2):327-39. doi: 10.1016/0006-8993(76)90273-0.
Lesions in cats, rats, and monkeys that spare more than 2% of the optic tract or visual cortex cause trivial deficits on most measures of vision. Overlap in the topography of the visual system may allow the spared remnant to 'see' a wider field of vision than the physiological map predicts. We tested whether monkeys left with only the lower retinal-field portion of their striate map could see with information coming from the upper half of the retina. In 6 rhesus monkeys the ganglion fibers exiting from the lower half of both retinae were cut with a photocoagulator. Later, the portion of area 17 which, according to the electrophysiological map, controls upper retinal vision, was ablated bilaterally. The combined retinal and striate lesions overlapped to include the entire visual field. Together they produced cortical blindness. The monkeys' performance of two pattern and object tasks remained at chance throughout the survival period. A previous study has described considerable sparing of vision after combined optic tract and visual cortex lesions in cats. Differences in the lesion methods and in the anatomy of the cat and monkey visual system may explain the disagreement.
在猫、大鼠和猴子身上，若视束或视觉皮层的损伤保留超过2%，在大多数视力测量指标上只会导致轻微缺陷。视觉系统拓扑结构的重叠可能使剩余的保留部分能“看到”比生理图谱预测更广阔的视野。我们测试了仅保留其纹状图谱下半部分视网膜视野的猴子是否能用来自视网膜上半部分的信息视物。在6只恒河猴中，用激光凝固器切断了来自双眼下半部分视网膜的神经节纤维。之后，根据电生理图谱，双侧切除了17区中控制视网膜上半部分视觉的区域。视网膜和纹状区的联合损伤重叠起来，覆盖了整个视野。它们共同导致了皮质盲。在整个存活期内，猴子在两项图案和物体任务中的表现一直处于随机水平。先前的一项研究描述了猫在视束和视觉皮层联合损伤后视力有相当程度的保留。损伤方法以及猫和猴子视觉系统解剖结构的差异可能解释了这种分歧。
