Which sequence correctly describes the main visual pathway from retina to cortex?

• A. Retina to Pretectal Nucleus to LGN to Cortex
• B. Retina to LGN to Primary Visual Cortex
• C. Retina to Suprachiasmatic Nucleus to LGN to Cortex
• D. Retina to LGN to Pretectal Nucleus

Answer: (B)

The main path for conscious vision goes from the retina to the lateral geniculate nucleus (LGN) in the thalamus, and from there to the primary visual cortex in the occipital lobe. Signals travel from retinal ganglion cells through the optic nerve, cross at the optic chiasm, continue in the optic tract to the LGN, and then reach the primary visual cortex via the optic radiations (geniculocalcarine fibers) to the calcarine cortex. The pretectal nucleus is involved in the pupil light reflex, and the suprachiasmatic nucleus handles circadian timing, not the main pathway for cortical visual perception. Therefore, retina → LGN → primary visual cortex best describes the primary pathway.