The Role of Visual Input in Setting up Spatial Filters in the Human Visual System

At birth the visual system can detect only big objects that are high in contrast. The adult visual system can resolve, with high precision, small objects that are in low contrast. We present a series of studies that provide insight into the role of visual input in the development of the neural architecture underlying human spatial vision. We conclude that the limits to spatial vision during normal development appear to result primarily from retinal immaturities. However, in the absence of early visual experience, the limits to spatial vision appear to be mainly cortical in origin. The early visual input-from the low spatial frequencies to which the infant's vision is known to be limited-sets up the neural architecture that will eventually become fine-tuned to high spatial frequencies.