The parafovea may refer to a position at a visual angle of approximately 4° from the normal fixation point or to the region extending to that angle from the fovea. It is compositionally distinguished from the fovea by its lower cone and ganglion cell densities and by its higher rod density. As may be expected, these differences affect its visual perception characteristics. Its spatial contrast sensitivity, visual acuity, and other visual attributes are lower than those of the fovea, but, as shown by its critical fusion frequency (CFF), its temporal frequency resolution extends to higher frequencies than that of the fovea. Its color perception is essentially the same as that of the fovea, but under low luminance, it becomes similar to tritanopic diachronic perception. These characteristics can be inferred from the relative distribution of the three cone types in the parafoveal retina. In reading, moreover, parafoveal information contributes to line...
KeywordsFoveal Region Parafoveal Word Parafoveal Processing Parafoveal Information Macular Pigment Density
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