Studies of visual development show that basic metrics of visual
development such as spatial resolution develop over the first 6–9
months in monkeys and over the first 6 or so years in humans. However,
more complex visual functions may develop over different, or more
protracted, time courses. To address the question of whether global
perceptual processing is linked to or otherwise dependent on the
development of basic spatial vision, we studied the development of
contour integration, a global perceptual task, in comparison to that of
grating acuity in macaque monkeys. We find that contour integration
develops substantially later than acuity. Contour integration begins to
develop at 5–6 months, near the time that acuity development is
complete and continues to mature well into the second postnatal year.
We discuss this later development in terms poor central efficiency and
consider the relevant anatomy and physiology of the developing visual
system. We conclude that contour integration is not likely to be
limited by the same mechanisms that are permissive to acuity
development, and may instead reflect the emergence of function central
to V1.