What is the difference between optic chiasm optic nerve and optic tract?

Asked By: Olexandr Linder | Last Updated: 14th April, 2020
Category: medical health eye and vision conditions
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Axons caudal to the intersection, called the optic chiasm, are optic tract fibers. Axons from retinal cells in the lateral portions of the retina project to the optic chiasm, but they do not cross the midline. They remain ipsilateral and travel to occipital (visual) cortex on the ipsilateral side.

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Furthermore, what is the difference between the optic nerve and the optic tract?

-optic tract fibers from both eyes which is 60% crosses the optic chiasm and 40% continue to the thalamus and midbrain targets on the same side. protectum is the collection of neurons that lies between the thalamus and the midbrain.

Also, what happens to the optic nerves at the optic chiasm? Optic chiasma Crucial to vision, the left and right optic nerves intersect at the chiasm, thus creating the hallmark X-shape. One-half of each nerve's axons (their long, threadlike portions) enters the opposite tract at this location, making it a partial decussation (crossing).

Likewise, people ask, what does the optic tract do?

The left optic nerve and the optic tracts. The optic tract (from the Latin tractus opticus) is a part of the visual system in the brain. It is a continuation of the optic nerve that relays information from the optic chiasm to the ipsilateral lateral geniculate nucleus (LGN), pretectal nuclei, and superior colliculus.

Why is optic nerve a tract?

The optic nerve is formed by the convergence of axons from the retinal ganglion cells. These cells in turn receive impulses from the photoreceptors of the eye (the rods and cones). After its formation, the nerve leaves the bony orbit via the optic canal, a passageway through the sphenoid bone.

37 Related Question Answers Found

How does the optic chiasm work?

The optic chiasm is an X-shaped structure formed by the crossing of the optic nerves in the brain. 1? It is thought that the crossing and uncrossing optic nerve fibers that travel through the optic chiasm developed in such a way to aid in binocular vision and eye-hand coordination.

What does the optic tract contain?

Each optic tract contains the fibres from the ipsilateral temporal and contralateral nasal retina. Thus, the right optic tract contains fibres from the right halves of the right and left retinae, and the left optic tract from the left halves of the right and left retinae of the eyeballs.

What would happen if the optic chiasm was damaged?

Damage to the retina or one of the optic nerves before it reaches the chiasm results in a loss of vision that is limited to the eye of origin. The resulting loss of vision is confined to the temporal visual field of each eye and is known as bitemporal hemianopsia.

Where does the optic nerve go in the brain?

The optic nerve connects the retina to the visual cortex in the back of the brain.

Where is optic chiasm located?


It is located at the bottom of the brain immediately inferior to the hypothalamus. The optic chiasm is found in all vertebrates, although in cyclostomes (lampreys and hagfishes), it is located within the brain.

What is the visual pathway of the eye?

The visual pathway is the pathway over which a visual sensation is transmitted from the retina to the brain. This includes a cornea and lens that focuses images on the retina, and nerve fibers that carry the visual sensations from the retina through the optic nerve.

How many optic nerves are there?

There are twelve cranial nerves. In terms of its embryonic development, the optic nerve is a part of the central nervous system (CNS) rather than a peripheral nerve. The word "optic" comes from the Greek "optikos", pertaining to sight. Aside from the optic nerve, the eye has a number of other components.

What structures make up the optic chiasm?

The chiasm contains decussating axons from both optic nerves. Axons arising from the retinal ganglion cells nasal to the fovea that carry information from the temporal visual fields cross the midline to join the axons from the temporal retinal and form the optic tracts.

What happens if you cut the left optic tract?

The entire left optic nerve would be cut and there would be a total loss of vision from the left eye. Damage at site #2: partial damage to the left optic nerve. In this case, loss of vision of the right side. Partial damage to these fiber tracts can cause other predictable visual problems.

How does the optic nerve work?


How does the optic nerve work? The optic nerve is a cable of nerve fibers that carry electrical impulses from the retina to the brain. The ganglion cells in turn transmit visual information along their axons to the visual centers of the brain. It is there that the electrical impulses are interpreted into sight.

Are optic nerves one or two?

Nerve signals travel along the optic nerve from each eye. The two optic nerves meet at the optic chiasm. There, the optic nerve from each eye divides, and half of the nerve fibers from each side cross to the other side.

What area receives input from the optic tract?

It receives a major sensory input from the retina. The LGN is the main central connection for the optic nerve to the occipital lobe, particularly the primary visual cortex. In humans, each LGN has six layers of neurons (grey matter) alternating with optic fibers (white matter).

What is Meyer's loop?

The Meyer loop is part of the optic radiation which sweeps back on itself into the temporal lobe, just lateral to the temporal horn of the lateral ventricle. It can be injured in temporal lobectomy, resulting in a superolateral field cut, the so called pie-in-the-sky field cut.

Where do optic tract axons terminate?

Most of the axons of the optic nerve terminate in the lateral geniculate nucleus from where information is relayed to the visual cortex, while other axons terminate in the pretectal nucleus and are involved in reflexive eye movements.

How is the right optic tract different from the right optic nerve?


Optic tract. The left optic tract transfers information from temporal retinal fibers from the left eye and nasal retinal fiber from the right eye. The right optic tract transfers information from the temporal retinal fibers from the right eye and nasal retinal fibers from the left eye.

What is the optic radiation?

The optic radiation (also known as the geniculocalcarine tract, the geniculostriate pathway, and posterior thalamic radiation) are axons from the neurons in the lateral geniculate nucleus to the primary visual cortex.

Where do axons in the left optic tract terminate in the human brain?

Information from the right visual field (now on the left side of the brain) travels in the left optic tract. Information from the left visual field travels in the right optic tract. Each optic tract terminates in the lateral geniculate nucleus (LGN) in the thalamus.