The Neural Control of Vision
M. The Processing of Shape

But there is one other major problem in animals with forward looking eyes. Contrary to what Cajal had proposed, when stimuli cross the midline, they do not activate cells on the cortical surface in a continuous fashion, as shown on the right in Figures 69 and 70. How this situation is resolved at higher levels in the visual system to permit the pattern analysis of which we are capable is one of the future research tasks.