Where is the lateral geniculate body located?

Category: medical health brain and nervous system disorders
4.7/5 (79 Views . 21 Votes)
They wrap around the midbrain and cross the medial surface of the temporal lobe, and 80% of them then terminate in a synaptic relay called the lateral geniculate nucleus (LGN), located in the dorsal part of the thalamus. The LGN is thus the major target for each optic tract.



Correspondingly, where is the lateral geniculate body?

The lateral geniculate nucleus (LGN; also called the lateral geniculate body or lateral geniculate complex) is a relay center in the thalamus for the visual pathway. It receives a major sensory input from the retina.

Subsequently, question is, what happens if the lateral geniculate nucleus is damaged? Damage at site #4 and #5: damage to the optic tract (#4) or the fiber tract from the lateral geniculate to the cortex (#5) can cause identical visual loss. In this case, loss of vision of the right side. Partial damage to these fiber tracts can cause other predictable visual problems.

Considering this, how many lateral geniculate nucleus are there?

…which extend to the two lateral geniculate nuclei (LGN) in the thalamus. The LGN act as way stations on the pathway to the primary visual cortex, in the occipital (rear) area of the cerebral cortex.

What is similar about the structure of the retina and the lateral geniculate nucleus?

Like the retina, the lateral geniculate nucleus is a laminated structure, in this case, with six principal layers of cells (Figure 15.3B). Thin layers of the smallest cells (i.e., the koniocellular neurons) are interposed between these principal layers.

35 Related Question Answers Found

What is meant by the visual pathway?

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.

What does the thalamus do?

The thalamus relays sensory impulses from receptors in various parts of the body to the cerebral cortex. A sensory impulse travels from the body surface towards the thalamus, which receives it as a sensation. This sensation is then passed onto the cerebral cortex for interpretation as touch, pain or temperature.

What do Koniocellular cells do?

Koniocellular layers are located ventral to each parvocellular and magnocellular layer of the LGN. Koniocellular cells are a heterogeneous population differing in many aspects, such as response properties and connectivity.

What is Retinotopic mapping?

Retinotopy (from Greek τόπος, place) is the mapping of visual input from the retina to neurons, particularly those neurons within the visual stream.

Why is lateral inhibition important?


Lateral inhibition increases the contrast and sharpness in visual response. This phenomenon already occurs in the mammalian retina. This mechanism also creates the Mach band visual effect. Visual lateral inhibition is the process in which photoreceptor cells aid the brain in perceiving contrast within an image.

What is the pathway?

The dorsal stream (or, "where pathway") leads to the parietal lobe, which is involved with processing the object's spatial location relative to the viewer and with speech repetition.

What does Magnocellular mean?

Medical Definition of magnocellular
: being or containing neurons with large cell bodies motion and depth perception processed by the magnocellular visual pathway — compare parvocellular.

Where is the medial geniculate nucleus?

The medial geniculate nucleus (MGN) or medial geniculate body (MGB) is part of the auditory thalamus and represents the thalamic relay between the inferior colliculus (IC) and the auditory cortex (AC).

What senses does lateral inhibition affect?

Lateral inhibition occurs in sensory systems of the body including olfactory, visual, tactile, and auditory systems.

Where are Hypercomplex cells located?


These cells are found specifically in layer IV, at which most outgoing projections from the LGN terminate. The receptive fields of simple cells are non-concentric and linear, in which excitatory and inhibitory regions exist adjacent to one another.

What are simple cells?

Anatomical terminology
A simple cell in the primary visual cortex is a cell that responds primarily to oriented edges and gratings (bars of particular orientations). These cells were discovered by Torsten Wiesel and David Hubel in the late 1950s.

Which neurons are found in the lateral geniculate nucleus LGN?

Directionally selective (DS) neurons are found in the retina and lateral geniculate nucleus (LGN) of rabbits and rodents, and in rabbits, LGN DS cells project to primary visual cortex.

Where are simple cells located?

Simple Cells are V1 neurons that respond to stimuli with particular orientations to objects within their receptive field. Like cells in the lateral geniculate nucleus (LGN), they have clear excitatory and inhibitory regions.

Why do ocular dominance columns form in v1?

Ocular dominance columns are stripes of neurons in the visual cortex of certain mammals (including humans) that respond preferentially to input from one eye or the other. The columns span multiple cortical layers, and are laid out in a striped pattern across the surface of the striate cortex (V1).

Where is the Pretectum located?


Location and structure. The pretectum is a bilateral group of highly interconnected nuclei located near the junction of the midbrain and forebrain.

Are eyes contralateral?

contralateral eye. the eye located on the opposite side of the body to another structure or object. For example, layer 6 of the left lateral geniculate nucleus receives input from the retinal ganglion cell axons that originate in the right (i.e., contralateral) eye. Compare ipsilateral eye.

Where is the thalamus located?

The thalamus is a small structure within the brain located just above the brain stem between the cerebral cortex and the midbrain and has extensive nerve connections to both. The main function of the thalamus is to relay motor and sensory signals to the cerebral cortex.