Question

Why is so much of the cerebral cortex devoted to sensory and motor connections to the eyes?

Answer 1

Possibly because it is an interface. It is a part of the function, but not really larger than other sensory areas of the cerebral cortex. We may know WHAT it does, but not really WHY it is done there.

Explanation:

For detailed discussion of the regions and functions of the cerebral cortex, see:
http://www.dartmouth.edu/~rswenson/NeuroSci/chapter_11.html