ESTIMATION AND APPLICATION OF THE HUMAN CORTICAL MAGNIFICATION FACTOR
ESTIMATION AND APPLICATION OF THE HUMAN CORTICAL MAGNIFICATION FACTOR
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DOI：
10.1007/bf00236819
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发表时间：
1979-01-01
影响因子：
2
通讯作者：
VIRSU, V
中科院分区：
文献类型：
--
作者：
ROVAMO, J;VIRSU, V
比较已发表的视网膜神经节细胞感受野密度D和皮质放大系数M的数据表明，在灵长类动物中，M2与D成正比。因此，可以从视网膜神经节细胞的密度分布和中央锥体的密度来估计视野的主要经络的人体M。利用之前发表的经验数据，我们估计了人类M值，并将其表示为四个简单的方程，可用于计算视野中任何位置的M值。M的单目值不是径向对称的，这些解析表示的M值使得预测视野中任何位置的对比度灵敏度和分辨率成为可能。我们测量了25个不同位置的对比敏感度函数，发现可以通过将测试栅格的视网膜尺寸与M的倒数值进行缩放来使功能相似。通过估计M的单个恒定乘数，可以准确地预测所有视网膜位置的视觉敏感度和分辨率。结果表明，视觉系统的功能和结构特性在整个视网膜上是非常密切和相似的。例如，视力与视网膜神经节细胞在视野的所有位置执行的采样密度具有相同的最佳关系。
Comparisons of the published data on the density D of receptive fields of retinal ganglion cells and on the cortical magnification factor M indicated that M2is directly proportional to D in primates. Therefore, the human M can be estimated for the principal meridians of the visual field from the density-distribution of retinal ganglion cells and from the density of the centralmost cones. Using the previously published empirical data, we estimated the values of the human M and express the values in four simple equations that can be used for finding the value of M for any location of the visual field. The monocular values of M are not radially symmetric.These analytically expressed values of M make it possible to predict contrast sensitivity and resolution for any location of the visual field. We measured contrast sensitivity functions at 25 different locations and found that the functions could be made similar by scaling the retinal dimensions of test gratings by the inverse values of M. Visual acuity and resolution could be predicted accurately for all retinal locations by means of a single constant multiplier of the estimated M.The results indicate that the functional and structural properties of the visual system are very closely and similarly related across the whole retina. Visual acuity, e.g., bears the same optimal relation to the density of sampling executed by retinal ganglion cells at all locations of the visual field.