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- Glossary
Parvocellular
"Parvus" means "small." In the lateral geniculate nucleus, the switching station for visual stimuli in the thalamus, the outer four layers are called parvocellular because, unlike the magnocellular cell layers, they have small cell bodies. The parvocellular system transmits information for the perception of color and fine details.
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- Glossary
Primary auditory cortex
The first processing station in the cerebral cortex for auditory information. The primary auditory cortex is located in the Heschl's gyrus and receives inputs from the medial geniculate nucleus of the thalamus. It is organized tonotopically – its neurons are arranged continuously according to frequency.
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- Glossary
Pulvinar
The pulvinar is a fairly large nucleus in the posterior thalamus that is connected to many visual centers. It appears to increase the excitability of cells in the visual cortex as soon as a stimulus is noticed. Some studies suggest that the pulvinar may also indirectly support language processing via cortical connections.
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- Glossary
Visual pathway
The visual pathway refers to the network of nerve cells involved in visual perception. In mammals, it runs from the retinal ganglion cells in the eye – as the optic nerve to the optic chiasm, then as the visual tract – via the only switching point in the lateral geniculate nucleus to the primary visual cortex.
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- Glossary
Visual radiation
The optic radiation – also known as Gratiolet's optic radiation after its discoverer – distributes visual impulses from the lateral geniculate nucleus to the comparatively very large primary visual cortex.
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- Glossary
Optic tract
The optic tract refers to the optic nerve after half of the fibers have crossed sides at the optic chiasm. However, it still consists of the axons (long fiber-like extensions) of the retinal ganglion cells. Most of the optic tract ends in the lateral geniculate nucleus, while others end in the superior colliculi, among other places.
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- Glossary
Soma
The cell body, also known as the soma, is the metabolic center of the cell. In addition to the cell organelles – such as the mitochondria – it also contains the cell nucleus with the genetic material. The dendrites and axon (long, fiber-like extension of nerve cells) extend from the cell body.
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- Glossary
Subthalamus
The subthalamus is an area of the diencephalon located ventrally below the thalamus. It includes the subthalamic nucleus, which functionally belongs to the basal ganglia network. The subthalamus plays an important role in the regulation and inhibition of movement sequences and in impulse control.
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- Glossary
Tegmentum
Tegmentum (from the Latin "tegere," meaning "to cover"). This is the ventral part of the midbrain located beneath the aqueduct. It contains nuclei such as the substantia nigra, the reticular formation, the cranial nerve nuclei, and the red nucleus.
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- Glossary
Tuber cinereum
The tuber cinereum is a hill-shaped area in the hypothalamus from which the infundibulum, the pituitary stalk, originates. The tuber nuclei are located in the tuber cinereum, including the nucleus tuberomammillaris, which is the only region in the brain that uses histamine as a neurotransmitter.
