The occipital lobes were obtained after death from six adult subjects with monocular visual loss. Flat-mounts were processed for cytochrome oxidase (CO) to reveal metabolic activity in the primary (V1) and secondary (V2) visual cortices. Mean V1 surface area was 2643 mm2 (range, 1986–3477 mm2). Ocular dominance columns were present in all cases, having a mean width of 863 μm. There were 78–126 column pairs along the V1 perimeter. Human column patterns were highly variable, but in at least one person they resembled a scaled-up version of macaque columns. CO patches in the upper layers were centered on ocular dominance columns in layer 4C, with one exception. In this individual, the columns in a local area resembled those present in the squirrel monkey, and no evidence was found for column/patch alignment. In every subject, the blind spot of the contralateral eye was conspicuous as an oval region without ocular dominance columns. It provided a precise landmark for delineating the central 15° of the visual field. A mean of 53.1% of striate cortex was devoted to the representation of the central 15°. This fraction was less than the proportion of striate cortex allocated to the representation of the central 15° in the macaque. Within the central 15°, each eye occupied an equal territory. Beyond this eccentricity, the contralateral eye predominated, occupying 63% of the cortex. In one subject, monocular visual loss began at age 4 months, causing shrinkage of ocular dominance columns. In V2, which had a larger surface area than V1, CO stripes were present but could not be classified as thick or thin.
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机译:死亡后从六名单眼视力丧失的成年受试者中获得枕叶。对细胞色素氧化酶(CO)进行平置处理以揭示初级(V1)和次级(V2)视皮层的代谢活性。 V1的平均表面积为2643 mm 2 sup>(范围1986–3477 mm 2 sup>)。在所有情况下都存在眼控柱,平均宽度为863μm。沿着V1周边有78–126个色谱柱对。人类柱的模式变化很大,但是至少在一个人中,它们类似于猕猴柱的放大版本。上层中的CO色块以第4C层中的眼优势柱为中心,但有一个例外。在这个人中,局部区域的柱子类似于松鼠猴中的柱子,并且没有发现柱子/斑块对齐的证据。在每个受试者中,对侧眼的盲点明显为椭圆形区域,没有眼优势柱。它为描绘视野的中心15°提供了精确的地标。纹状皮质的平均53.1%用于表示中心15°。该分数小于为猕猴的中心15°分配的条纹状皮质的比例。在中心15°以内,每只眼睛占据相等的区域。除了这种偏心之外,对侧眼占主导地位,占皮质的63%。在一名受试者中,单眼视力丧失始于4个月大,导致眼优势柱缩小。在具有比V1更大的表面积的V2中,存在CO条带,但不能分类为厚或薄。
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