The optic chiasm, by allowing and facilitating the decussation of part of the optical fibers, allows both hemispheres of the brain to receive visual information from both eyes: if it were not produced (or a decussation of all the fibers were produced), the information received by each eye would be processed only by one of them, without a good integration of the material.
| Optic chiasm | |
|---|---|
| Function | Transmit visual information from the optic nerves to the occipital lobes of the brain |
| Identifiers | |
| Latin | chiasma opticum |
| MeSH | D009897 |
Optic chiasma. The optic chiasm or optic chiasma is an X-shaped space, located in the forebrain, directly in front of the hypothalamus. 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 the optic chiasm stage, it is estimated that 53% of optic nerve axons, predominantly nasal hemiretine, decuse to join the strands of the contralateral temporal hemiretine forming the optic tract. This decussation is intended to combine visual input data from two halves of each retina receiving light from the same part of the visual field.
Once the optic nerves meet at the optic chiasm, axons from half of each retina cross over to the opposite side of the brain. The axons from the other half of the retina remain on the same side of the brain. After the partial crossover of nerve fibers at the optic chiasma, the resulting two bundles of fibers are called the optic tracts.
Optic chiasma The optic chiasm or optic chiasma is an X-shaped space, located in the forebrain, directly in front of the hypothalamus. Crucial to vision, the left and right optic nerves intersect at the chiasm, thus creating the hallmark X-shape.
The optic chiasm This decussation aims to combine visual input information from the two halves of each retina that receive light from the same portion of the visual field. The majority of optic tract axons synapse in the lateral geniculate nucleus (LGN) of the thalamus.
The optic nerve connects the brain to the eye. To biologists, the optic chiasm is thought to be a turning point in evolution. 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.
The optic chiasm, or optic chiasma, is the part of the brain where the optic nerves cross and is therefore of primary importance to the visual pathway. It is located at the base of the brain inferior to the hypothalamus, and approximately 10 mm superior to the pituitary gland within the suprasellar cistern.
The purpose of the optic chiasm is to ensure that visual signals go to both hemispheres of brain. The majority of neural signals are sent to the thalamus for processing and are then distributed into areas of the occipital lobe.
- At the optic chiasm, the optic nerve fibers from the nasal halves of the retinas cross to the opposite sides, where they join the fibers from the opposite temporal retinas to form the optic tracts.
Small branches of the anterior cerebral artery and the superior hypophyseal artery supply the chiasm and intracranial portion of the optic nerves whereas the optic tracts are supplied by small branches of the anterior choroidal and posterior communicating arteries.
physician Esmail JorjaniIn the same period, in Persia, the physician Esmail Jorjani (1042–1137) was the first who identified in the optic chiasm the crossing of fibres, and the physiological significance of this was viewed as the earliest description of this phenomenon [57].
The optic chiasm is a part of the brain that is of great importance when it comes to processing visual information coming from the retina, being the point where the optic nerves of both eyes meet.
The optic chiasm, by allowing and facilitating the decussation of part of the optical fibers, allows both hemispheres of the brain to receive visual information from both eyes: if it were not produced (or a decussation of all the fibers were produced), the information received by each eye would be processed only by one of them, without a good integration of the material..
Head injuries, surgeries or cerebrovascular accidents, together with some diseases and disorders such as tumors, can be the reason that the optic chiasm or the nerve pathways that circulate through it are injured. Although it is not frequent, given its position within the skull, this injury can cause a great effect on our visual system.
Adel K. Afifi. (2006). Functional neuroanatomy: Text and atlas. México D.F .: McGraw Hill p.324
What is the optic chiasma and how does it helps with vision? The optic chiasm is an X-shaped structure created through the crossing of the brain's optic nerves. The optic nerve connects the eye to the brain. The optic chiasm is believed to be a turning point in evolution for biologists. Crossing and uncrossing optic nerve fibres travelling ...
This decussation is intended to combine visual input data from two halves of each retina receiving light from the same part of the visual field.
The function of Optic Chiasm: The optic chiasm plays a crucial role in visual input information retinotopic depiction and is situated above the pituitary gland, anterior to the pituitary stalk, and inferior to the hypothalamus. At optic chiasm stage, it is estimated that 53% of optic nerve axons, predominantly nasal hemiretine, ...
The optic chiasm is believed to be a turning point in evolution for biologists. Crossing and uncrossing optic nerve fibres travelling through the optic chiasm are believed to have evolved in such a way to help with binocular vision and eye-hand coordination.
A pituitary adenoma is the most prevalent disease affecting the optic chiasm. Pituitary adenomas are benign tumours. They do not affect at all in most cases, but in some instances, they may influence vision, sometimes causing vision loss. As pituitary adenomas grow in size, they can put pressure on essential structures in the body, such as the optic nerve. Pressing the optic nerve can cause blindness, so eye doctors must detect pituitary tumours before vision damage is caused.
When an illness or lesion affects the optic nerve before it hits the optic chiasm in the brain, the vision defect appears in one eye only and can change the whole field of the eye. Sometimes people who have a single defect do not realise it until one eye is covered.
Anatomy of Optic Chiasm: Nerve fibres from half of each retina at the optic chiasm cross over to the brain's opposite side. The other half of the retina's fibres travel to the same part of the brain. Each half of the brain gets visual signals from both eyes ' visual areas because of this intersection. The optic chiasm stretches at the level of the ...
The optic chiasm is a vital part of the brain’s visual pathway, and its health is essential for clear and comfortable binocular vision. Since it’s an internal structure of the eye, however, it can be difficult to know when there’s a problem with the optic chiasm.
The optic chiasm is located in the front part of the brain. It lies directly in front of the hypothalamus, the part of the brain that controls body temperature, hunger and mood.
The optical chiasm, by allowing and facilitating the decussation of part of the optical fibers, allows both cerebral hemispheres to receive visual information from both eyes : if it did not occur (or a decussation of all fibers occurred), the information received by each eye would be processed only by one of them, and there is no good integration of the material.
It is a small structure in the form of X (X) located in the anterior cerebral fossa, something above and in front of the diaphragm of the sella turcica (small niche in the sphenoid bone that houses the pituitary gland) and in front of the hypothalamus.
Vision is one of the most developed and important senses for the human being. In fact we have a cerebral lobe, the occipital, which has been linked especially to aspects related to vision and processing and integration of information from this sense.