![]() ![]() This has two reasons: first, the region of the visual field corresponding to the blind spot of one eye is covered by the fellow eye, and in this way the left and right eyes compensate for each other’s blind spots in binocular vision. Although the blind spot has been revealed by retinotopic mapping of the human primary visual cortex (V1) ( Tootell et al., 1998 Awater et al., 2005), we never experience a dark hole in our visual field instead, we perceive a complete visual world. This area is known as the physiological blind spot which is located in the temporal visual field with its center at approximately 15° and subtending 6 × 8° of visual angle ( Armaly, 1969 Ramachandran, 1992b Pessoa and De Weerd, 2003 Komatsu, 2006). ![]() The optic disk of the eye is formed by the ganglion cell axons exiting the eyeball on their way to the brain, resulting in a region on the retina where there are no photoreceptors and thus there should be no vision at all. These results suggest that the strength of filling-in decreases with distance from the fovea consistent with the decrease of the cortical magnification factor. Here, the two colors on the upper and lower sides of the blind spot filled in the enclosed area equally. This asymmetry was dependent on the relative size of the half rings, but not the two colors used, and was absent when the bi-colored annulus was rotated by 90°. Specifically, the color surrounding the nasal half typically filled in about 75% of the blind spot area, whereas the color surrounding the temporal half filled in only about 25%. By contrast, bi-colored annuli, where one half had a given color, while the other half had a different one, filled in the blind spot asymmetrically. ![]() We found that mono-colored annuli filled in the blind spot uniformly. Is there any retinotopic rule in the color filling-in of the blind spot? To find out, we used mono-colored and bi-colored annuli hugging the boundary of the blind spot. The study of filling-in enables us to better understand the creative nature of the visual system, which generates perceptual information where there is none. This is because the blind spot fills in with the brightness, color, texture, and motion of the surround. However, we rarely notice the existence of it in daily life. The physiological blind spot, corresponding to the optic disk in the retina, is a relatively large (6 × 8°) area in the visual field that receives no retinal input. State Key Laboratory of Neuroscience and Key Laboratory of Primate Neurobiology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.Hui Li †, Junxiang Luo †, Yiliang Lu, Janis Kan, Lothar Spillmann § and Wei Wang * ![]()
0 Comments
Leave a Reply. |