optic tract

anatomy

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June 17, 2026

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The optic tract is a crucial part of the visual pathway in the brain. It begins after the optic nerves partially cross at the optic chiasm. Fibers from the nasal (inner) half of each retina cross to the opposite side of the brain, while fibers from the temporal (outer) half remain on the same side. This partial crossing ensures that information from the right visual field is processed by the left side of the brain, and vice versa.12345

The optic tracts then carry this visual information to various brain regions, primarily the lateral geniculate nuclei in the thalamus. From there, further pathways lead to the visual cortex in the occipital lobe, where conscious perception of vision occurs. Damage to the optic tract can result in partial blindness in both eyes, known as hemianopia.2345

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human nervous system
Optic nerve (CN II or 2)
In this way the optic tracts, which extend from the chiasm to the thalamus, contain fibers conveying information from both eyes. Injury to one optic nerve therefore results in total blindness of that eye, while damage to the optic tract on one side results in partial blindness in both…
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In this way the optic tracts, which extend from the chiasm to the thalamus, contain fibers conveying information from both eyes. Injury to one optic nerve therefore results in total blindness of that eye, while damage to the optic tract on one side results in partial blindness in both…
Read More

human eye
The visual pathway
…this point are called the optic tracts, containing nerve fibres from both retinas. The result of the partial decussation is that an object in, say, the right-hand visual field produces effects in the two eyes that are transmitted to the left-hand side of the brain only. With cutaneous (skin) sensation…
Read More
…this point are called the optic tracts, containing nerve fibres from both retinas. The result of the partial decussation is that an object in, say, the right-hand visual field produces effects in the two eyes that are transmitted to the left-hand side of the brain only. With cutaneous (skin) sensation…
Read More