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Rubro-olivary Tract
The rubro-olivary tract (rubroolivary fibers) is a nerve tract, tract which connects the inferior olivary nucleus, and the parvocellular red nucleus. It is hypothesized that it uses both the corticospinal tract, corticospinal and rubrospinal tracts. References External links * http://www.ucsf.edu/nreview/02.1-Anatomy-Brain&SC/Cerebellum.html Central nervous system pathways {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve Tract
A nerve tract is a bundle of nerve fibers (axons) connecting Nucleus (neuroanatomy), nuclei of the central nervous system. In the peripheral nervous system, this is known as a nerve fascicle, and has associated nervous tissue, connective tissue. The main nerve tracts in the central nervous system are of three types: association fibers, commissural fibers, and projection fibers. A nerve tract may also be referred to as a commissure, decussation, or neural pathway. A commissure connects the two cerebral hemispheres at the same levels, while a decussation connects at different levels (crosses obliquely). Types The nerve fibers in the central nervous system can be categorized into three groups on the basis of their course and connections. Different tracts may also be referred to as ''projections'' or ''radiations'' such as thalamocortical radiations. Association fibers The tracts that connect cortical areas within the same hemisphere are called Association fiber, association tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Olivary Nucleus
The inferior olivary nucleus (ION) is a structure found in the medulla oblongata underneath the superior olivary nucleus.Gado, Thomas A. Woolsey; Joseph Hanaway; Mokhtar H. (2003). The brain atlas a visual guide to the human central nervous system (2nd ed.). Hoboken, NJ: Wiley. p. 206. . In vertebrates, the ION is known to coordinate signals from the spinal cord to the cerebellum to regulate motor coordination and learning.Schweighofer N, Lang EJ, Kawato M. Role of the olivo-cerebellar complex in motor learning and control. ''Frontiers in Neural Circuits''. 2013;7:94. . These connections have been shown to be tightly associated, as degeneration of either the cerebellum or the ION results in degeneration of the other. Neurons of the ION are glutamatergic and receive inhibitory input via GABA receptors. There are two distinct GABAα receptor populations that are spatially organized within each neuron present in the ION. The GABAα receptor make-up varies based on where the rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parvocellular Red Nucleus
The parvocellular red nucleus (RNp) is located in the rostral midbrain and is involved in motor coordination. Together with the magnocellular red nucleus, it makes up the red nucleus The red nucleus or nucleus ruber is a structure in the rostral midbrain involved in motor coordination. The red nucleus is pale pink, which is believed to be due to the presence of iron in at least two different forms: hemoglobin and ferritin. .... References Midbrain Brainstem nuclei {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticospinal Tract
The corticospinal tract is a white matter motor pathway starting at the cerebral cortex that terminates on lower motor neurons and interneurons in the spinal cord, controlling movements of the limbs and trunk. There are more than one million neurons in the corticospinal tract, and they become myelinated usually in the first two years of life. The corticospinal tract is one of the pyramidal tracts, the other being the corticobulbar tract The corticobulbar (or corticonuclear) tract is a two-neuron white matter motor pathway connecting the motor cortex in the cerebral cortex to the Medullary pyramids (brainstem), medullary pyramids, which are part of the brainstem's medulla oblonga .... Anatomy The corticospinal tract originates in several parts of the brain, including not just the motor areas, but also the primary somatosensory cortex and premotor areas. Most of the neurons originate in either the primary motor cortex (precentral gyrus, Brodmann area 4) or the premotor fron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubrospinal Tract
The rubrospinal tract is one of the descending tracts of the spinal cord. It is a motor control pathway that originates in the red nucleus. It is a part of the lateral indirect extrapyramidal tract. The rubrospinal tract fibers are efferent nerve fibers from the magnocellular part of the red nucleus. (Rubro-olivary fibers are efferents from the parvocelluar part of the red nucleus). It is functionally less important in humans. It is involved in motor control of distal flexors of the upper limbespecially of the hand and fingersby promoting flexor tone while inhibiting extensors. Structure The rubrospinal tract originates in the magnocellular red nucleus in the midbrain, and decussates (crosses over) at the midline in the anterior tegmental decussation. In the pons, it is situated medially within the rostral pontine tegmentum. In the medulla oblongata, it descends within the lateral tegmentum medial to the spinocerebellar tract, and posterior to the spinothalamic tract. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
