The Visual-Origin Theory of Neural Decussation: A Design-Based Explanation for Contralateral Control

This manuscript introduces the Visual-Origin Theory of Neural Decussation, a novel functional model explaining the consistent contralateral wiring seen in vertebrate nervous systems. Rather than attributing this arrangement to developmental twisting or assumed evolutionary processes, the theory presents vision, particularly peripheral vision, as the central organizing feature of neural architecture. It proposes that decussation is a purposeful design enabling rapid, spatially aligned motor responses to visual stimuli, particularly in survival-relevant contexts. Supported by anatomical observations and geometric efficiency, the theory offers a coherent alternative to existing structural or speculative accounts.