Humans’ eyes are both set on the front of the face to allow binocular vision where focus and fixation on an object by both eyes create a single visual image. Problems with focus and fixation could result in blur, eyestrain or double vision. The external eye muscles have to be in alignment, synchronised in gaze …
All of the muscles in each eye must be coordinated by the brain for binocular vision to function.
Complex neural networks link numerous structures. Interactions exist between these structures within each system separately, as well as between both systems. The ideal is for the best possible acuity of each eye, binocular (stereoscopic) vision, alignment of the eyes and accurate movements and saccades.
Strabismus may have sensory and/or motor origins from the peripheral and/or central nervous system (brain and spinal cord )
Peripheral origin is at the level of the oculomotor muscles themselves or their innervation.