AnatomyDiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPsychiatry and PsychologyPhenomena and Processes
Optic ChiasmRetinaOptic NerveDiencephalonReceptor, EphB1Retinal Ganglion CellsOptic AtrophyVisual PathwaysAlbinismHemianopsiaAxonsOptic Nerve NeoplasmsOptic DiskOptic Lobe, NonmammalianOptic NeuritisAnophthalmosEyeReceptor, EphB2Optic Nerve InjuriesOptic Nerve DiseasesGeniculate BodiesEphrin-B2Pituitary NeoplasmsCrossing Over, GeneticNerve FibersPituitary ApoplexyVisual FieldsEye EnucleationSella TurcicaNeurogliaCarbocyaninesMagnetic Resonance Imaging
FibersMeet at the optic chiasmCells in the retinaAxonsPhotoreceptorsForm the optic nerveFibresContralateralGanglion cellsMidlineBrainTractsPhotoreceptorAnteriorNasal retinaMedialCentral retinaTemporal retinaFoveaFoveal hypoplasiaNerves crossAbnormalitiesIndicated optic nerveIpsilateralRods and cPathwayLensNeuralNeuronsChoroidLeft opticCarriesSensoryRetinasThalamusAbnormalityScleraSignals travelRadiationImpulsesActivatesHemispherePeripheralHuman albinismLightGlaucomaRight visual fieldChiasmal
Fibers11
Meet at the optic chiasm1
Cells in the retina3
Axons17
  • The first step of this integration is possible anatomically with the segregation of contralateral and ipsilateral axons at the optic chiasm. (umontreal.ca)
  • Contralateral axons cross the chiasm midline as they progress from the optic nerve to the optic tract. (umontreal.ca)
  • In contrast, ipsilateral axons deviate from the chiasm and continue in the ipsilateral optic tract. (umontreal.ca)
  • Together with the presence of Shh at the midline, this complementary expression pattern led us to hypothesize that Shh might repel ipsilateral RGC axons at the chiasm. (umontreal.ca)
  • In vivo, we show that Boc is required for the normal segregation of ipsilateral axons at the optic chiasm and, conversely, that Boc expression in contralateral RGCs prevents their axons from crossing the optic chiasm. (umontreal.ca)
  • Half of the RGCs send their axons to the same side of the brain while the other half cross over, allowing for binocular vision. (cajalclub.org)
  • Dr. Mason is investigating how the axons know whether to cross over or remain on the same side at the optic chiasm. (cajalclub.org)
  • Most axons in the optic nerve are connected to the lateral geniculate nucleus of the thalamus for processing to perception, while the others transmit information to the superior colliculus of the midbrain, which helps control eye movements. (explorable.com)
  • The neural signals initially processed by the retina travel via the axons of the ganglion cells through the optic nerves, dividing and partially crossing over into the optic chiasm and then travelling via the optic tracts to the lateral geniculate nucleus (LGN). (medscape.com)
  • The axons of the ganglion cells form the optic nerve, which carries information to the brain. (medscape.com)
  • Neural signals from the rods and cones undergo processing by other neurons, whose output takes the form of action potentials in retinal ganglion cells whose axons form the optic nerve. (wikipedia.org)
  • The optic chiasm is a key structure in the visual system, where the fate of axons from the retina is decided, such that axons carrying information from the right visual hemifield are guided to the left hemisphere and vice versa. (frontiersin.org)
  • In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). (lecturio.com)
  • The corpus callosum of L1-minus mice was reduced in size because of the failure of many callosal axons to cross the midline. (jneurosci.org)
  • The axons that cross originate largely from the medial or nasal aspect of each retina. (veteriankey.com)
  • There are an estimated 47245 ± 4000 axons in this optic nerve in an area of 71,947 microns². (mbl.org)
  • Axons from the retinal ganglion cells converge and exit through the back of the eye to form the optic nerve. (ucf.edu)
Photoreceptors7
  • The rods' photoreceptors (called rhodopsin) can detect a single photon, and will transmit a chemical signal along the optic nerve to the brain. (arkitek.com)
  • It is itself an extension of the optic nerve and contains the photoreceptors that allow you to see. (bmrhc.net)
  • [6] In contrast, in the cephalopod retina, the photoreceptors are in front, with processing neurons and capillaries behind them. (wikipedia.org)
  • Although the overlying neural tissue is partly transparent, and the accompanying glial cells have been shown to act as fibre-optic channels to transport photons directly to the photoreceptors, [7] [8] light scattering does occur. (wikipedia.org)
  • The retina houses photoreceptors, interneurons, and ganglion cells. (brainfacts.org)
  • Photoreceptors send signals to ganglion cells and interneurons, which process and relay information out of the retina. (brainfacts.org)
  • There are no photoreceptors where the optic nerve meets the retina, creating a "blind spot. (brainfacts.org)
Form the optic nerve1
  • The second or optic nerve consists of nerve fibres which spring from the ganglion cells of the retina, and converge to the optic papilla, where they are grouped together to form the optic nerve. (co.ma)
Fibres6
  • The gross anatomy of the optic nerves and chiasma has been studied, and differences in the tension in the crossed and uncrossed fibres after chiasmal displacement have been investigated. (bmj.com)
  • Bitemporal hemianopia, as well as associated or independent hemianopic scotomata, results from stretching of the crossing fibres in the chiasma. (bmj.com)
  • Binasal hemianopia results from compression of the uncrossed fibres in the optic nerve or chiasma by the anterior cerebral or internal carotid arteries. (bmj.com)
  • The crossed and uncrossed fibres of the optic chiasma differ not only anatomically in the areas of retina in which they arise but also physically. (bmj.com)
  • In the anterior part of the cleft between the two thalami, and immediately in front of the columns of the fornix, a round bundle of fibres crosses the median plane. (co.ma)
  • Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses that are sent to various visual centres of the brain through the fibres of the optic nerve . (wikipedia.org)
Contralateral3
  • In human albinism a part of the temporal retina projects abnormally to the contralateral hemisphere. (arvojournals.org)
  • In humans, the nasal retina projects to the contralateral hemisphere, whereas the temporal retina projects ipsilaterally. (arvojournals.org)
  • Contralateral visual field information from the lateral retina projects to the ipsilateral brain, whereas ipsilateral visual field information has to decussate at the optic chiasm to reach the opposite side of the brain. (usk.ac.id)
Ganglion cells1
Midline1
  • In the caudal hindbrain, the corticospinal tract crosses the midline in the pyramidal decussation and continues down the spinal cord as the lateral corticospinal tract. (unboundmedicine.com)
Brain25
  • Additionally, neural connections between the retina and the brain are altered if melanin in the retina is absent during development. (medscape.com)
  • Damage to the optic pathway or visual cortex in the left brain-perhaps from a stroke-can cause complete loss of the right visual field. (jrank.org)
  • The optic nerve from each eye splits into two halves at the optic chiasm, each portion continuing on to only one of the two cerebral hemispheres of the brain. (essayta.com)
  • whereas the optic nerve portion bearing signals from the temporal half of each eye projects only to the ipsilateral (same side) brain hemisphere. (essayta.com)
  • Greek and Roman humoral physiology needed a hollow optic nerve, the obstruction of which prevented the flow of visual spirit to and from the brain and resulted in blindness. (nature.com)
  • The signals made by these cells are transmitted through the optic nerve toward the brain. (cognifit.com)
  • This is a thin, delicate lamina which may be seen on the basal aspect of the brain, stretching from the upper aspect of the optic chiasma in an upward direction to become connected with the anterior end of the corpus callosum. (co.ma)
  • The optic nerve carries the visual sensory input from the eye to the brain. (explorable.com)
  • The optic nerve from each eye carries impulses to the brain, where visual information is interpreted. (msdmanuals.com)
  • Damage to an optic nerve or damage to its pathways to the brain results in loss of vision. (msdmanuals.com)
  • Action potentials (nerve impulses) generated from retinal rods and cones are relayed to the visual cortex of the brain via the optic nerves. (tomsk.ru)
  • Think of the retina as a movie screen on which everything that you see is displayed and interpreted by your brain as 3D images. (bmrhc.net)
  • The optic nerves extend from the back of each eye and join together in the brain at the optic chiasm. (bmrhc.net)
  • From the optic chiasm, the nerve signals travel along two optic tracts in the brain, and eventually to the occipital cortex, where vision is perceived. (bmrhc.net)
  • The right visual field information in the left optic nerve (from the lateral retina) is already on the correct (left) side of the brain, but the right visual field information in the right optic nerve (from the medial retina) must cross from the right optic nerve to the left side of the brain to join it. (mhmedical.com)
  • Because of the interocular distance, which results in objects of different distances falling on different spots of the two retinae, the brain can extract depth perception from the two-dimensional information of the visual field. (usk.ac.id)
  • thus, the retina is considered part of the central nervous system (CNS) and is actually brain tissue. (wikipedia.org)
  • Like most of the brain, the retina is isolated from the vascular system by the blood-brain barrier . (wikipedia.org)
  • therefore, the optic nerve must cross through the retina en route to the brain. (wikipedia.org)
  • First, the brain compares amounts of light hitting small, adjacent areas on the retina. (brainfacts.org)
  • Cells send signals along optic nerves to the brain. (brainfacts.org)
  • carries visual information from the retina to the brain. (ucf.edu)
  • As Figure 3 shows, the optic chiasm is an X-shaped structure that sits just below the cerebral cortex at the front of the brain. (ucf.edu)
  • At the point of the optic chiasm, information from the right visual field (which comes from both eyes) is sent to the left side of the brain, and information from the left visual field is sent to the right side of the brain. (ucf.edu)
  • This illustration shows the optic chiasm at the front of the brain and the pathways to the occipital lobe at the back of the brain, where visual sensations are processed into meaningful perceptions. (ucf.edu)
Tracts2
  • The two optic tracts end at the thalamus, particularly in the lateral geniculate nucleus (LGN). (explorable.com)
  • additionally reporting thinner optic nerves and wider angles between optic tracts. (frontiersin.org)
Photoreceptor3
  • The small photoreceptor cells of the retina (the inner surface at the back of the eye) sense light and transmit impulses to the optic nerve. (msdmanuals.com)
  • and finally reaches the photoreceptor cells of the retina. (medscape.com)
  • While cones are concentrated in the fovea, where images tend to be focused, rods, another type of photoreceptor, are located throughout the remainder of the retina. (mrcpsych.uk)
Anterior7
  • The optic chiasma crosses the floor in front and marks the place where the latter becomes continuous with the anterior wall of the cavity. (co.ma)
  • The anterior wall of the third ventricle is formed by the lamina terminalis, which extends upwards from the optic chiasma. (co.ma)
  • The anterior commissure, as it crosses from one side to the other, projects into the ventricle, but, of course, it is excluded from the cavity by the ventricular epithelial lining. (co.ma)
  • In summary, the orbit communicates with the middle cranial fossa (via the optic canal and superior orbital fissure), the infratemporal and pterygopalatine fossae ( via the inferior orbital fissure), the inferior meatus of the nose (via the nasolacrimal canal), the nasal cavity (via the anterior ethmoidal foramen), and the face ( via supraorbital and infraorbital foramina). (dartmouth.edu)
  • These light rays pass through the anterior and posterior segments of the eye and are focused onto the retina by the action of the lens. (medscape.com)
  • Standard International Society for Clinical Electrophysiology of Vision (ISCEV) protocols [1] assess the anterior visual pathway (eye, optic nerve anterior to the optic chiasm). (eyewiki.org)
  • The peak time and amplitude of the waveforms denote the function of optic nerve anterior to the optic chiasm. (eyewiki.org)
Nasal retina1
Medial2
  • The nerve pathways from the medial retina (closest to the nose) cross back of the eye at the optic chiasm. (sixwords.in)
  • Thus the images from the left medial retina crosses to the right occipital lobe and the images from the right medial retina cross to the left occipital lobe. (sixwords.in)
Central retina1
  • [9] Some vertebrates, including humans, have an area of the central retina adapted for high-acuity vision. (wikipedia.org)
Temporal retina2
  • This is particularly relevant because some early VEP reports on albinism indicate that only part of the temporal retina is misrouted. (arvojournals.org)
  • 8 Moreover, they indicate the possibility of a great interindividual variability of the extent by which the line of decussation is shifted to the temporal retina. (arvojournals.org)
Fovea3
  • The central area of your retina, called the fovea - is where you actually capture what you're focusing on. (arkitek.com)
  • Within the retina is the yellow area called macula, and in it is the fovea which is the center for the best visual acuity. (explorable.com)
  • The greatest concentration of cones is found in the macula and fovea at the center of the retina. (bmrhc.net)
Foveal hypoplasia1
  • The changes to the optic system associated with hypopigmentation include decreased visual acuity secondary to foveal hypoplasia and misrouting of the optic nerves at the chiasm. (medscape.com)
Nerves cross2
  • It first goes through the optic chiasma (where the optic nerves cross, making the information received from the right field of vision go to the left hemisphere, and information received from the left field of vision go to the right hemisphere), and is then relayed to the lateral geniculate nucleus of the thalamus. (cognifit.com)
  • The SCN is a tiny nucleus that's positioned just above the optic chiasm, the place where the two optic nerves cross. (humanos.me)
Abnormalities3
  • The fact that the CNN recognition of the optic chiasm fails for chiasm abnormalities in PWA underlines the fundamental differences in their spatial features. (frontiersin.org)
  • PURPOSE: To describe the optic nerve head (ONH) abnormalities in nonpathologic highly myopic eyes based on swept-source optical coherence tomography (OCT) and the relationship with visual field (VF). (bvsalud.org)
  • We differentiated between 3 major types (optic disc morphologic abnormality, papillary/peripapillary tissue defect, and papillary/peripapillary schisis) and 12 subtypes of ONH abnormalities. (bvsalud.org)
Indicated optic nerve1
  • Medieval physicians understood that the presence of a fixed dilated pupil indicated optic nerve obstruction, preventing the passage of visual spirit, and that cataract surgery in such cases would not restore sight. (nature.com)
Ipsilateral1
  • The studies presented in this thesis show that the Sonic Hedgehog (Shh) receptor Boc is enriched in ipsilateral RGCs of the developing retina. (umontreal.ca)
Rods and c1
  • The vertebrate retina is inverted in the sense that the light-sensing cells are in the back of the retina, so that light has to pass through layers of neurons and capillaries before it reaches the photosensitive sections of the rods and cones. (wikipedia.org)
Pathway2
Lens6
  • During the Renaissance, the organ of vision was transferred from the lens to the optic nerve, which was generally believed to be on the axis of the eye. (nature.com)
  • The cornea and the lens are like a tag-team as they bend light together, focusing it on the retina. (explorable.com)
  • Muscles adjust the curve in the lens to focus clear images on the retina. (bmrhc.net)
  • Your inner eye or the space between the posterior chamber behind the lens and the retina is the vitreous body. (bmrhc.net)
  • Light rays pass through the gel on their way from the lens to the retina. (bmrhc.net)
  • The lens bends light, focusing it onto the retina, a sheet of cells lining the inner surface of your eyeball. (brainfacts.org)
Neural3
  • Situated at the back of the eye, the retina is the part where electromagnetic energy is turned into neural energy. (explorable.com)
  • although, in humans, they only have an indirect response to light, as detected at the retina, through a series of complex neural pathways (Zhao et al, 2019). (tomsk.ru)
  • The neural retina consists of several layers of neurons interconnected by synapses and is supported by an outer layer of pigmented epithelial cells. (wikipedia.org)
Neurons5
  • These cross over each other at the optic chiasm (Fig 3), above which is a specialised collection of around 10,000 neurons called the suprachiasmatic nucleus (SCN). (tomsk.ru)
  • Neurons in the SCN have an inherent 24-hour rhythm synchronised to cues in light intensity detected by the retina (Challet, 2015). (tomsk.ru)
  • Some nerves that we usually think of as purely afferent or sensory, such as the optic nerve for vision, and the vestibulocochlear nerve, for hearing and balance, also have a small component of efferent motor neurons that can modify the function of the end organ by altering transmission at the receptor site. (veteriankey.com)
  • Such efferent neurons have been described in the retina of the eye and the membranous labyrinth of the inner ear. (veteriankey.com)
  • After collecting behavioral data, hypothalamic slices were prepared and evoked EPSCs (eEPSCs) were recorded from SCN neurons by stimulating the optic chiasm. (eneuro.org)
Choroid2
  • The choroid is the lining underneath the retina. (bmrhc.net)
  • The choroid contains blood vessels that supply your retina with blood and oxygen to keep it healthy. (bmrhc.net)
Left optic1
  • The visual input on the right visual field goes in the left optic tract, while that from the let visual field is transmitted to the right optic tract. (explorable.com)
Carries1
Sensory1
  • A sensory branch of the mandibular nerve (CN V3) It passes through the parotid gland en route to the ear, where it innervates skin of the pinna, external auditory canal, and tympanic membrane. (unboundmedicine.com)
Retinas1
  • pl. retinae or retinas ) is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs . (wikipedia.org)
Thalamus1
  • The optic nerve projections to each visual cortex pass first to a 6-layered structure called the lateral geniculate nucleus (LGN), in a polysensory organ of the midbrain called the thalamus. (essayta.com)
Abnormality1
  • Because of the great interindividual variability of the projection abnormality, studies of the contribution of the abnormally projecting retina to visual perception must be preceded by the localization of the abnormality. (arvojournals.org)
Sclera1
  • The nerve pierces the outer layers of the retina, the chorioid, and the sclera. (co.ma)
Signals travel1
Radiation1
Impulses1
  • The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then processes that image within the retina and sends nerve impulses along the optic nerve to the visual cortex to create visual perception . (wikipedia.org)
Activates1
  • A receptive field activates when light hits the region on the retina corresponding to the center of its field. (brainfacts.org)
Hemisphere1
  • Posterior to the optic chiasm, visual information is organized into fields: the left visual field is processed in the right hemisphere, and the right visual field in the left hemisphere. (mhmedical.com)
Peripheral2
  • Other features include photophobia, iris transillumination, nystagmus, and pigment deficiency in the peripheral retina. (medscape.com)
  • High concentrations of rods at the outer portions of your retina act as motion detectors in your peripheral or side vision. (bmrhc.net)
Human albinism1
Light6
  • Although comprised of ten layers, the retina is transparent for better light passage. (explorable.com)
  • The receptor cells and the bipolar cells of the retina respond to light with graded electrotonic responses, rather than with all-or-nothing action potentials. (medscape.com)
  • Melatonin secretion is governed by light levels perceived by the retina. (tomsk.ru)
  • A main purpose of the eye is to focus light on the retina. (bmrhc.net)
  • Like a camera capturing images, light on the retina creates a two-dimensional reversed image. (brainfacts.org)
  • The eye captures and projects light onto the retina. (brainfacts.org)
Glaucoma1
  • The optic chiasm volume differed significantly between the control and advanced NTG groups ( p = 0.0003) and between early and advanced glaucoma patients ( p = 0.004). (mdpi.com)
Right visual field2
  • This means that some visual information from the right half of each retina (from the left visual field) travels to the right visual cortex, and visual information from the left half of each retina (from the right visual field) travels to the left visual cortex. (jrank.org)
  • likewise the right media retina sees objects laterally in the right visual field. (sixwords.in)
Chiasmal1
  • Chiasmal disorder causes a crossed asymmetry and retrochiasmal dysfunction causes uncrossed asymmetry. (eyewiki.org)