Pearlman A L, Birch J, Meadows J C
Ann Neurol. 1979 Mar;5(3):253-61. doi: 10.1002/ana.410050307.
In contrast to the traditional view that striate visual cortex (area 17) is surrounded by two homogeneous cortical areas (areas 18 and 19), recent studies have shown that mammalian extrastriate visual cortex contains several anatomically and functionally distinct subregions. One such region, the V-4 complex of the rhesus monkey, is highly specialized for the analysis of color information, suggesting that a lesion in a homologous region might produce a defect in color vision while sparing other visual functions. We have studied a patient whose clinical syndrome supports this suggestion: a 44-year-old man with normal color vision suffered two cerebral infarctions that produced first a right and then a left superior homonymous quadrantanopia and also caused prosopagnosia, topographical disorientation, and severely impaired color vision. Computed tomography demonstrated extensive lesions in both inferior occipital lobes in the territories of the lateral branches of the posterior cerebral arteries, involving the lingual and medial occipitotemporal gyri bilaterally; these gyri contain the inferior portion of striate cortex and segments of extrastriate visual cortex. The patient had no difficulty in giving the correct color names associated with common objects presented either verbally or in outline drawings. Standardized testing with the Farnsworth-Munsell 100-hue test, the Nagel anomaloscope, and a method that tests for just-noticeable differences between monochromatic stimuli all showed that the patient's ability to distinguish one color from another was markedly imparied but not totally absent. In contrast, visual acuity, reading, visually guided eye movements, and stereopsis were normal. Cells in the V-4 complex of monkey extrastriate cortex are highly specialized for distinguishing one color from another; the hue discrimination deficit that was demonstrated in this patient with cerebral color blindness indicates that a region or regions with similar function has been damaged.
与传统观点认为纹状视觉皮层（17区）被两个同质的皮层区域（18区和19区）所包围不同，最近的研究表明哺乳动物的纹外视觉皮层包含几个在解剖学和功能上不同的亚区域。其中一个这样的区域，恒河猴的V - 4复合体，高度专门用于颜色信息的分析，这表明同源区域的损伤可能会导致色觉缺陷，而其他视觉功能则不受影响。我们研究了一位患者，其临床综合征支持了这一观点：一名44岁色觉正常的男性发生了两次脑梗死，首先导致右侧然后左侧同向性上象限盲，还引起了面容失认、地形定向障碍和严重的色觉受损。计算机断层扫描显示双侧大脑后动脉外侧分支区域的枕叶下部有广泛病变，累及双侧舌回和枕颞内侧回；这些脑回包含纹状皮层的下部和纹外视觉皮层的部分区域。患者在说出与口头或轮廓图呈现的常见物体相关的正确颜色名称方面没有困难。使用法恩斯沃思 - 芒塞尔100色调测试、纳格尔色盲检查镜以及一种测试单色刺激之间刚刚可察觉差异的方法进行的标准化测试均表明，患者区分一种颜色与另一种颜色的能力明显受损，但并非完全丧失。相比之下，视力、阅读、视觉引导的眼球运动和立体视觉均正常。猴纹外皮层V - 4复合体中的细胞高度专门用于区分一种颜色与另一种颜色；该脑性色盲患者所表现出的色调辨别缺陷表明具有类似功能的一个或多个区域已受损。
