This is a neuroanatomy lesson on the visual pathway, describing the mechanism by which retinal, optic-nerve, optic-chiasm, optic-tract, thalamic (lateral geniculate nucleus), and optic-radiation structures sort and relay visual information from each eye's visual field to the appropriate cerebral hemisphere and cortical location. The core principle is retinotopic and hemifield lateralization: nasal retinal fibers decussate at the optic chiasm while temporal fibers remain ipsilateral, so that each visual hemifield is represented in the contralateral primary visual cortex, and each vertical hemifield (upper/lower) is represented in the opposite (inferior/superior) bank of the calcarine sulcus due to image inversion at the cornea. It belongs to the neuroanatomy/neuroscience domain, specifically the organization of sensory (visual) pathways, and connects to broader cortical processing theory via the downstream dorsal ("where/how") and ventral ("what") streams.
This is a neuroanatomy lesson on the visual pathway, describing the mechanism by which retinal, optic-nerve, optic-chiasm, optic-tract, thalamic (lateral geniculate nucleus), and optic-radiation stru…