Differential development of two visual functions in primates.

Psychophysical data suggest that spatial resolution and spatial position sensitivity may be limited by different neural mechanisms. We investigated this hypothesis from a developmental perspective by studying the development of these two kinds of visual performance in two groups of infant macaque monkeys (Macaca nemestrina), one normal and one given an experimental strabismus. The results show that these two visual functions develop at different rates in normal monkeys and are disrupted differentially by abnormal early visual experience. However the relationship between the two measures is the same in strabismic and normally reared monkeys; the performance of strabismic monkeys resembles that of younger normal monkeys.