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Encyclopedia > Cerebellum
Brain: Cerebellum
Figure 1a: A human brain, with the cerebellum in purple.
Figure 1b: MRI image showing a mid-sagittal view of the human brain, with the cerebellum in purple.
Part of Brain
Artery SCA, AICA, PICA
Vein superior, inferior
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The cerebellum (Latin: "little brain") is a region of the brain that plays an important role in the integration of sensory perception and motor control. In order to coordinate motor control, there are many neural pathways linking the cerebellum with the cerebral motor cortex (which sends information to the muscles causing them to move) and the spinocerebellar tract (which provides proprioceptive feedback on the position of the body in space). The cerebellum integrates these pathways, like a train conductor, using the constant feedback on body position to fine-tune motor movements.[1] Image File history File links Human brain with the cerebellum highlighted in purple. ... A human brain. ... Image File history File links Deskulled sagittal MRI with cerebllum highlighted in purple. ... MRI redirects here. ... The anatomical planes The anatomical position is a schematic convention for describing the relative morphology of the human body. ... For other uses, see Brain (disambiguation). ... The superior cerebellar artery arises near the termination of the basilar. ... The anterior inferior cerebellar artery passes backward to be distributed to the anterior part of the under surface of the cerebellum, anastomosing with the posterior inferior cerebellar branch of the vertebral. ... The posterior inferior cerebellar artery (PICA) is one of the three main arterial blood supplies for the cerebellum. ... The superior cerebellar veins pass partly forward and medialward, across the superior vermis, to end in the straight sinus and the internal cerebral veins, partly lateralward to the transverse and superior petrosal sinuses. ... The inferior cerebellar veins are of large size, end in the transverse, superior petrosal, and occipital sinuses. ... Image File history File links No higher resolution available. ... For other uses, see Latins and Latin (disambiguation). ... For other uses, see Brain (disambiguation). ... In psychology and the cognitive sciences, perception is the process of acquiring, interpreting, selecting, and organizing sensory information. ... In vertebrates, motoneurons (also called motor neurons) are efferent neurons that originate in the spinal cord and synapse with muscle fibers to facilitate muscle contraction and with muscle spindles to modify proprioceptive sensitivity. ... A neural pathway is a neural tract connecting one part of the nervous system with another, usually consisting of bundles of elongated, myelin insultated neurons, known collectively as white matter. ... The telencephalon (IPA: ) is the name for the forebrain, a large region within the brain to which many functions are attributed. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... For other uses of Muscles, see Muscles (disambiguation). ... The spinocerebellar tract is a set of axonal fibers originating in the spinal cord and terminating in the cerebellum. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ...


Because of this 'updating' function of the cerebellum, lesions within it are not so debilitating as to cause paralysis, but rather present as feedback deficits resulting in disorders in fine movement, equilibrium, posture, and motor learning. Initial observations by physiologists during the 18th century indicated that patients with cerebellar damage show problems with motor coordination and movement. Research into cerebellar function during the early to mid 19th century was done via lesion and ablation studies in animals. Research physiologists noted that such lesions led to animals with strange movements, awkward gait, and muscular weakness. These observations and studies led to the conclusion that the cerebellum was a motor control structure.[1] However, modern research shows that the cerebellum has a broader role in a number of key cognitive functions, including attention and the processing of language, music, and other sensory temporal stimuli.[2] Skin lesions caused by Chickenpox A lesion is any abnormal tissue found on or in an organism, usually damaged by disease or trauma. ... Paralysed redirects here. ... For other uses, see Feedback (disambiguation). ... Equilibrioception or sense of balance is one of the physiological senses. ... Human position refers to a position of a human body. ... Motor learning is the process of improving the smoothness and accuracy of movements. ... This article or section does not cite any references or sources. ... Explain the dystonias connected with motor coordination. ... For other uses, see Animal (disambiguation). ... This article is about psychological concept of attention. ... For other uses, see Music (disambiguation). ...

Contents

General features

The cerebellum is located in the inferior posterior portion of the head (the hindbrain), directly dorsal to the pons, and inferior to the occipital lobe (Figs. 1 and 3). Because of its large number of tiny granule cells, the cerebellum contains more than 50% of all neurons in the brain, but it only takes up 10% of total brain volume.[3] The cerebellum receives nearly 200 million input fibers; in contrast, the optic nerve is composed of a mere one million fibers. The rhombencephalon (or hindbrain) is a developmental categorization of portions of the central nervous system in vertebrates. ... For other uses, see Pons (disambiguation). ... The occipital lobe is the visual processing center of the mammalian brain, containing most of the anatomical region of the visual cortex. ... In neuroscience, granule cells are tiny cells found within the granular layer of the cerebellum. ... This article is about cells in the nervous system. ... This article is about the anatomical structure. ...


The cerebellum is divided into two large hemispheres, much like the cerebrum, and contains ten smaller lobules. The cytoarchitecture (cellular organization) of the cerebellum is highly uniform, with connections organized into a rough, three-dimensional array of perpendicular circuit elements. This organizational uniformity makes the nerve circuitry relatively easy to study. To envision this "perpendicular array," one might imagine a tree-lined street with wires running straight through the branches of one tree to the next.[clarify] For other uses, see Sphere (disambiguation). ... The telencephalon (te-len-seff-a-lon) is the technical name for a large region within the brain which is attributed many functions, which some groups would class as unique features which make humans stand out from other species. ... Cytoarchitectonics represents the study of the microscopic, cellular composition of structures within the body. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... 2-dimensional renderings (ie. ... For the microarray in genetics, see SNP array. ... In cognitive neuroscience, a neural network (also known as a neuronal network or biological neural network to distinguish from artificial neural networks) is a population of interconnected neurons. ...


Development and evolution

Figure 2: Drawing of the cells in the chicken cerebellum by S. Ramón y Cajal.
Figure 2: Drawing of the cells in the chicken cerebellum by S. Ramón y Cajal.

During the early stages of embryonic development, the brain starts to form in three distinct segments: the prosencephalon, mesencephalon, and rhombencephalon. The rhombencephalon is the most caudal (toward the tail) segment of the embryonic brain; it is from this segment that the cerebellum develops. Along the embryonic rhombencephalic segment develop eight swellings, called rhombomeres. The cerebellum arises from two rhombomeres located in the alar plate of the neural tube, a structure that eventually forms the brain and spinal cord. The specific rhombomeres from which the cerebellum forms are rhombomere 1 (Rh.1) caudally (near the tail) and the "isthmus" rostrally (near the front).[4] Image File history File links Drawing of the cells of the chick cerebellum by Santiago Ramón y Cajal, from Estructura de los centros nerviosos de las aves, Madrid, 1905?. File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Drawing of the cells of the chick cerebellum by Santiago Ramón y Cajal, from Estructura de los centros nerviosos de las aves, Madrid, 1905?. File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... This article or section does not adequately cite its references or sources. ... Santiago Ramón y Cajal Santiago Ramón y Cajal (May 1, 1852 – October 17, 1934) was a famous Spanish histologist, physician, and Nobel laureate. ... Embryogenesis is the process by which the embryo is formed and develops. ... In the anatomy of vertebrates, the prosencephalon is a part of encephalon, or brain. ... In biological anatomy, the mesencephalon (or midbrain) is the middle of three vesicles that arise from the neural tube that forms the brain of developing animals. ... The rhombencephalon (or hindbrain) is a developmental categorization of portions of the central nervous system in vertebrates. ... In the vertebrate embryo, a rhombomere is a segment of the developing rhombencephalon. ... The alar plate (or alar lamina) is a neural structure in the embryonic nervous system, part of the dorsal side of neural tube, that involves the communication of general somatic and general visceral sensory impulses. ... In the developing vertebrate nervous system, the neural tube is the precursor of the central nervous system, which comprises the brain and spinal cord. ...


Two primary regions are thought to give rise to the neurons that make up the cerebellum. The first region is the ventricular zone in the roof of the fourth ventricle. This area produces Purkinje cells and deep cerebellar nuclear neurons. These cells are the primary output neurons of the cerebellar cortex and cerebellum. The second germinal zone (cellular birthplace) is known as the Rhombic lip, neurons then move by embryonic week 27 to the external granular layer. This layer of cells—found on the exterior the cerebellum—produces the granule neurons. The granule neurons migrate from this exterior layer to form an inner layer known as the internal granule layer. The external granular layer ceases to exist in the mature cerebellum, leaving only granule cells in the internal granule layer. The cerebellar white matter may be a third germinal zone in the cerebellum; however, its function as a germinal zone is controversial. The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. ... Drawing of pigeon Purkinje cells (A) by Santiago Ramon y Cajal Purkinje cells are a class of GABAergic neuron located in the cerebellar cortex. ... In neuroanatomy, a nucleus is a central nervous system structure that is composed mainly of gray matter, and which acts as a hub or transit point for electrical signals in a single neural subsystem. ... White matter is one of the two main solid components of the central nervous system. ...


The cerebellum is of archipalliar phylogenetic origin. The pallium is a term for gray matter that forms the cortex. The archipallium is one of the most evolutionarily primitive brain regions. The circuits in the cerebellar cortex look similar across all classes of vertebrates, including fish, reptiles, birds, and mammals (e.g., Fig. 2). This has been taken as evidence that the cerebellum performs functions important to all vertebrate species. In anatomy of animals, the archipallium the oldest region of the brains pallium. ... In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ... In the anatomy of animals, the pallium is a part of the brain that is the evolutionary precedent of the cerebrum. ... This article is about evolution in biology. ... A class is the rank in the scientific classification of organisms in biology below Phylum and above Order. ... This article does not cite any references or sources. ... For other uses, see Fish (disambiguation). ... Orders  Crocodilia - Crocodilians scary crocodiles. ... For other meanings of bird, see bird (disambiguation). ... Orders Subclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorpha Insectivora Chiroptera Pholidota Carnivora Perissodactyla Artiodactyla Cetacea Afrosoricida Macroscelidea Tubulidentata Hyracoidea Proboscidea Sirenia The mammals are the class of vertebrate animals primarily characterized by the presence of mammary... For other uses, see Species (disambiguation). ...


Anatomy

The cerebellum contains similar gray and white matter divisions as the cerebrum. Embedded within the white matter—which is known as the arbor vitae (Tree of Life) in the cerebellum due to its branched, treelike appearance—are four deep cerebellar nuclei. Three gross phylogenetic segments are largely grouped by general function. The three cortical layers contain various cellular types that often create various feedback and feedforward loops. Oxygenated blood is supplied by three arterial branches off the basilar and vertebral arteries. Grey matter (or gray matter) is a major component of the central nervous system, consisting of nerve cell bodies, glial cells (astroglia and oligodendrocytes), capillaries, and short nerve cell extensions/processes (axons and dendrites). ... The telencephalon (IPA: ) is the name for the forebrain, a large region within the brain to which many functions are attributed. ... The arbor vitae (Latin for Tree of Life) is the cerebellar white matter, so called for its branched, tree-like appearance. ... The coniferous Coast Redwood, the tallest tree species on earth. ... This article is about the chemical element and its most stable form, or dioxygen. ... For other uses, see Blood (disambiguation). ... Section of an artery For other uses, see Artery (disambiguation). ... The basilar artery is one of the arteries which the brain supplies with oxygen-rich blood. ... The vertebral arteries are branches of the subclavian arteries. ...


Divisions

The cerebellum can be divided according to three different criteria: gross anatomical, phyologenetical, and functional.


Gross anatomical divisions

On gross inspection, three lobes can be distinguished in the cerebellum: the flocculonodular lobe, the anterior lobe (rostral to the "primary fissure"), and the posterior lobe (dorsal to the "primary fissure"). The latter two can be further divided in a midline cerebellar vermis and lateral cerebellar hemispheres. Part of the structure of animal brains, the cerebellar vermis is a narrow, wormlike structure between the hemispheres of the cerebellum. ...

Figure 3: Cerebellum and surrounding regions; sagittal view of one hemisphere. A: Midbrain. B: Pons. C: Medulla. D: Spinal cord. E: Fourth ventricle. F: Arbor vitae. G: Tonsil. H: Anterior lobe. I: Posterior lobe.
Figure 3: Cerebellum and surrounding regions; sagittal view of one hemisphere. A: Midbrain. B: Pons. C: Medulla. D: Spinal cord. E: Fourth ventricle. F: Arbor vitae. G: Tonsil. H: Anterior lobe. I: Posterior lobe.
Figure 4: Schematic representation of the major anatomical subdivisions of the cerebellum. Superior view of an "unrolled" cerebellum, placing the vermis in one plane.

Image File history File links Diagram of cerebellar regions. ... Image File history File links Diagram of cerebellar regions. ... In biological anatomy, the mesencephalon (or midbrain) is the middle of three vesicles that arise from the neural tube that forms the brain of developing animals. ... For other uses, see Pons (disambiguation). ... The medulla oblongata is the lower portion of the brainstem. ... The Spinal cord nested in the vertebral column. ... The ventricular system is a set of structures in the brain continuous with the central canal of the spinal cord. ... The arbor vitae (Latin for Tree of Life) is the cerebellar white matter, so called for its branched, tree-like appearance. ... The cerebellar tonsil (amygdaline nucleus) is a rounded mass, situated in the hemispheres of the cerebellum. ... Image File history File links Download high resolution version (914x637, 66 KB)Schematic representation of the major anatomical divisions of the cerebellum. ... Image File history File links Download high resolution version (914x637, 66 KB)Schematic representation of the major anatomical divisions of the cerebellum. ...

Phylogenetic and functional divisions

The cerebellum can also be divided in three parts based on both phylogenetic criteria (the evolutionary age of each part) and on functional criteria (the incoming and outgoing connections each part has and the role played in normal cerebellar function). From the phylogenetically oldest to the newest, the three parts are: Phylogenetic groups, or taxa, can be monophyletic, paraphyletic, or polyphyletic. ...

Functional denomination (phylogenetic denomination) Anatomical parts Role
Vestibulocerebellum (Archicerebellum) Flocculonodular lobe (and immediately adjacent vermis) The vestibulocerebellum regulates balance and eye movements. It receives vestibular input from both the semicircular canals and from the vestibular nuclei, and sends fibres back to the medial and lateral vestibular nuclei. It also receives visual input from the superior colliculi and from the visual cortex (the latter via the pontine nuclei, forming a cortico-ponto-cerebellar pathway). Lesions of the vestibulocerebellum cause disturbances of balance and gait.
Spinocerebellum (Paleocerebellum) Vermis and intermediate parts of the hemispheres ("paravermis") The spinocerebellum regulates body and limb movements. It receives proprioception input from the dorsal columns of the spinal cord (including the spinocerebellar tract) as well as from the trigeminal nerve, as well as from visual and auditory systems. It sends fibres to deep cerebellar nuclei which in turn project to both the cerebral cortex and the brain stem, thus providing modulation of descending motor systems. The spinocerebellum contains sensory maps as it receives data on the position of various body parts in space: in particular, the vermis receives fibres from the trunk and proximal portions of limbs, while the intermediate parts of the hemispheres receive fibres from the distal portions of limbs. The spinocerebellum is able to elaborate proprioceptive input in order to anticipate the future position of a body part during the course of a movement, in a "feed forward" manner.
Cerebrocerebellum (Neocerebellum, Pontocerebellum) Lateral parts of the hemispheres The neocerebellum is involved in planning movement and evaluating sensory information for action. It receives input exclusively from the cerebral cortex (especially the parietal lobe) via the pontine nuclei (forming cortico-ponto-cerebellar pathways), and sends fibres mainly to the ventrolateral thalamus (in turn connected to motor areas of the premotor cortex and primary motor area of the cerebral cortex) and to the red nucleus (in turn connected to the inferior olivary nucleus, which links back to the cerebellar hemispheres). The neocerebellum is involved in planning movement that is about to occur[5] and has purely cognitive functions as well.

Much of what is understood about the functions of the cerebellum stems from careful documentation of the effects of focal lesions in human patients who have suffered from injury or disease or through animal lesion research. It has been suggested that Equilibrioception be merged into this article or section. ... See also Labyrinth, an article treating the mythical maze that imprisoned the Minotaur. ... The nuclei of the vestibular nerve. ... The visual system is the part of the nervous system which allows organisms to see. ... The Superior collici is an area in the mesencephalon of vertebrate brains. ... Brodmann area 17 (primary visual cortex) is shown in red in this image which also shows area 18 (orange) and 19 (yellow) The visual cortex refers to the primary visual cortex (also known as striate cortex or V1) and extrastriate visual cortical areas such as V2, V3, V4, and V5. ... The pontine nuclei are a part of the pons which store the memory of intention during motor activity. ... A gait can refer to: a particular way or manner of moving on foot: walking and running are the two basic human gaits; see also gait analysis and Gait (human). ... Proprioception (from Latin proprius, meaning ones own) is the sense of the position of parts of the body, relative to other neighbouring parts of the body. ... The Spinal cord nested in the vertebral column. ... The spinocerebellar tract is a set of axonal fibers originating in the spinal cord and terminating in the cerebellum. ... The trigeminal nerve is the fifth (V) cranial nerve, and carries sensory information from most of the face, as well as motor supply to the muscles of mastication (the muscles enabling chewing), tensor tympani (in the middle ear), and other muscles in the floor of the mouth, such as the... The auditory system is the sensory system for the sense of hearing. ... The parietal lobe is a lobe in the brain. ... The thalamus (from Greek θάλαμος = bedroom, chamber, IPA= /ˈθæləməs/) is a pair and symmetric part of the brain. ... The premotor cortex is an area of motor cortex in the frontal lobe of the brain, located in front of the primary motor cortex and behind the prefrontal cortex. ... The primary motor area is a group of networked cells in mammalian brains that controls movements of specific body parts associated with cell groups in that area of the brain. ... The red nucleus is a structure in the rostral midbrain involved in motor coordination. ... In anatomy, the olivary bodies or simply olives (Latin oliva) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. ...


Deep nuclei

The deep nuclei of the cerebellum act as the main centers of communication, and the four different nuclei of the cerebellum (dentate, interpositus, fastigial, and vestibular) receive and send information to specific parts of the brain. In addition, these nuclei receive both inhibitory and excitatory signals from other parts of the brain which in turn affect the nucleus's outgoing signals.[6] Figure 1a: A human brain, with the cerebellum in purple. ...


Cortical layers

Figure 5: Microcircuitry of the cerebellum. Excitatory synapses are denoted by (+) and inhibitory synapses by (-). MF: Mossy fiber. DCN: Deep cerebellar nuclei. IO: Inferior olive. CF: Climbing fiber. GC: Granule cell. PF: Parallel fiber. PC: Purkinje cell. GgC: Golgi cell. SC: Stellate cell. BC: Basket cell.
Figure 5: Microcircuitry of the cerebellum. Excitatory synapses are denoted by (+) and inhibitory synapses by (-). MF: Mossy fiber. DCN: Deep cerebellar nuclei. IO: Inferior olive. CF: Climbing fiber. GC: Granule cell. PF: Parallel fiber. PC: Purkinje cell. GgC: Golgi cell. SC: Stellate cell. BC: Basket cell.
Figure 6: Confocal micrograph from mouse cerebellum expressing green-fluorescent protein in Purkinje cells.

There are three layers to the cerebellar cortex; from outer to inner layer, these are the molecular, Purkinje, and granular layers. The function of the cerebellar cortex is essentially to modulate information flowing through the deep nuclei. The microcircuitry of the cerebellum is schematized in Figure 5. Mossy and climbing fibers carry sensorimotor information into the deep nuclei, which in turn pass it on to various premotor areas, thus regulating the gain and timing of motor actions. Mossy and climbing fibers also feed this information into the cerebellar cortex, which performs various computations, resulting in the regulation of Purkinje cell firing. Purkinje neurons feed back into the deep nuclei via a potent inhibitory synapse. This synapse regulates the extent to which mossy and climbing fibers activate the deep nuclei, and thus control the ultimate effect of the cerebellum on motor function. The synaptic strength of almost every synapse in the cerebellar cortex has been shown to undergo synaptic plasticity. This allows the circuitry of the cerebellar cortex to continuously adjust and fine-tune the output of the cerebellum, forming the basis of some types of motor learning and coordination. Each layer in the cerebellar cortex contains the various cell types that comprise this circuitry. Image File history File links Diagram of the cerebellar circuitry. ... Image File history File links Diagram of the cerebellar circuitry. ... Figure 5: Microcircuitry of the cerebellum. ... In anatomy, the olivary bodies or simply olives (Latin oliva) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. ... This article does not cite its references or sources. ... Parallel fibers arise from granule cells in the cerebellar cortex. ... Drawing of pigeon Purkinje cells (A) by Santiago Ramon y Cajal Purkinje cells are a class of GABAergic neuron located in the cerebellar cortex. ... Image File history File links Confocal micrograph of cerebellum from transgenic mouse expressing EGFP driven by an L7, Purkinje cell-specific promoter. ... Image File history File links Confocal micrograph of cerebellum from transgenic mouse expressing EGFP driven by an L7, Purkinje cell-specific promoter. ... Confocal laser scanning microscopy (CLSM or LSCM) is a valuable tool for obtaining high resolution images and 3-D reconstructions. ... A micrograph is a photograph or similar image taken through a microscope or similar device to show a magnified image of an item. ... This article is about the rodent. ... ... In neuroscience, the term fiber describes a bundle of axons projecting from one group of neurons in a specific area to another. ... This article does not cite its references or sources. ... In electronics, gain is usually taken as the mean ratio of the signal output of a system to the signal input of the system. ... Illustration of the major elements in a prototypical synapse. ... In neuroscience, synaptic plasticity is the ability of the connection, or synapse, between two neurons to change in strength. ...


Granular layer

The innermost layer contains the cell bodies of two types of cells: the numerous and tiny granule cells, and the larger Golgi cells. Mossy fibers enter the granular layer from their main point of origin, the pontine nuclei. These fibers form excitatory synapses with the granule cells and the cells of the deep cerebellar nuclei. The granule cells send their T-shaped axons—known as parallel fibers—up into the superficial molecular layer, where they form hundreds of thousands of synapses with Purkinje cell dendrites. The human cerebellum contains on the order of 60 to 80 billion granule cells, making this single cell type by far the most numerous neuron in the brain (roughly 70% of all neurons in the brain and spinal cord, combined). Golgi cells provide inhibitory feedback to granule cells, forming a synapse with them and projecting an axon into the molecular layer. In neuroscience, granule cells are tiny cells found within the granular layer of the cerebellum. ... In neuroscience, Golgi cells are inhibitory interneurons found within the granular layer of the cerebellum. ... Parallel fibers arise from granule cells in the cerebellar cortex. ... Dendrites (from Greek dendron, “tree”) are the branched projections of a neuron that act to conduct the electrical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project. ...


Purkinje layer

The middle layer contains only one type of cell body—that of the large Purkinje cell. Purkinje cells are the primary integrative neurons of the cerebellar cortex and provide its sole output. Purkinje cell dendrites are large arbors with hundreds of spiny branches reaching up into the molecular layer (Fig. 6). These dendritic arbors are flat—nearly all of them lie in planes—with neighboring Purkinje arbors in parallel planes. Each parallel fiber from the granule cells runs orthogonally through these arbors, like a wire passing through many layers. Purkinje neurons are GABAergic—meaning they have inhibitory synapses—with the neurons of the deep cerebellar and vestibular nuclei in the brainstem. Each Purkinje cell receives excitatory input from 100,000 to 200,000 parallel fibers. Parallel fibers are said to be responsible for the simple (all or nothing, amplitude invariant) spiking of the Purkinje cell. Drawing of pigeon Purkinje cells (A) by Santiago Ramon y Cajal Purkinje cells are a class of GABAergic neuron located in the cerebellar cortex. ... In mathematics, orthogonal is synonymous with perpendicular when used as a simple adjective that is not part of any longer phrase with a standard definition. ... It has been suggested that pulse amplitude be merged into this article or section. ...


Purkinje cells also receive input from the inferior olivary nucleus via climbing fibers. A good mnemonic for this interaction is the phrase "climb the other olive tree", given that climbing fibers originate from the contralateral inferior olive. In striking contrast to the 100,000-plus inputs from parallel fibers, each Purkinje cell receives input from exactly one climbing fiber; but this single fiber "climbs" the dendrites of the Purkinje cell, winding around them and making a large number of synapses as it goes. The net input is so strong that a single action potential from a climbing fiber is capable of producing a "complex spike" in the Purkinje cell: a burst of several spikes in a row, with diminishing amplitude, followed by a pause during which simple spikes are suppressed. In anatomy, the olivary bodies or simply olives (Latin oliva) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. ... This article does not cite its references or sources. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ...


Molecular layer

This outermost layer of the cerebellar cortex contains two types of inhibitory interneurons: the stellate and basket cells. It also contains the dendritic arbors of Purkinje neurons and parallel fiber tracts from the granule cells. Both stellate and basket cells form GABAergic synapses onto Purkinje cell dendrites. An interneuron (also called relay neuron,association neuron or bipolar neuron) is a term used to describe a neuron which has two different common meanings. ... In neuroscience, stellate cells are inhibitory interneurons found within the molecular layer of the cerebellum. ... Basket cells are inhibitory GABAergic interneurons found in the molecular layer of the cerebellum. ...


Peduncles

Similarly, the cerebellum follows the trend of "threes", with three major input and output peduncles (fiber bundles). These are the superior (brachium conjunctivum), middle (brachium pontis), and inferior (restiform body) cerebellar peduncles.

Peduncle Description
Superior While there are some afferent fibers from the anterior spinocerebellar tract that are conveyed to the anterior cerebellar lobe via this peduncle, most of the fibers are efferents. Thus, the superior cerebellar peduncle is the major output pathway of the cerebellum. Most of the efferent fibers originate within the dentate nucleus which in turn project to various midbrain structures including the red nucleus, the ventral lateral/ventral anterior nucleus of the thalamus, and the medulla. The dentatorubrothalamocortical (dentate nucleus > red nucleus > thalamus > premotor cortex) and cerebellothalamocortical (cerebellum > thalamus > premotor cortex) pathways are two major pathways that pass through this peduncle and are important in motor planning.
Middle This is composed entirely of afferent fibers originating within the pontine nuclei as part of the massive corticopontocerebellar tract (cerebral cortex > pons > cerebellum). These fibers descend from the sensory and motor areas of the cerebral neocortex and make the middle cerebellar peduncle the largest of the three cerebellar peduncles.
Inferior This carries many types of input and output fibers that are mainly concerned with integrating proprioceptive sensory input with motor vestibular functions such as balance and posture maintenance. Proprioceptive information from the body is carried to the cerebellum via the dorsal spinocerebellar tract. This tract passes through the inferior cerebellar peduncle and synapses within the paleocerebellum. Vestibular information projects onto the archicerebellum.
The climbing fibers of the inferior olive run through the inferior cerebellar peduncle.
This peduncle also carries information directly from the Purkinje cells out to the vestibular nuclei in the dorsal brainstem located at the junction between the pons and medulla.

There are three sources of input to the cerebellum, in two categories consisting of mossy and climbing fibers, respectively. Mossy fibers can originate from the pontine nuclei, which are clusters of neurons located in the pons that carry information from the contralateral cerebral cortex. They may also arise within the spinocerebellar tract whose origin is located in the ipsilateral spinal cord. Most of the output from the cerebellum initially synapses onto the deep cerebellar nuclei before exiting via the three peduncles. The most notable exception is the direct inhibition of the vestibular nuclei by Purkinje cells. The superior cerebellar peduncles (brachia conjunctiva), two in number, emerge from the upper and medial part of the white substance of the hemispheres and are placed under cover of the upper part of the cerebellum. ... The ventral spinocerebellar tract conveys proprioceptive information from the body to the cerebellum. ... Figure 1a: A human brain, with the cerebellum in purple. ... In biological anatomy, the mesencephalon (or midbrain) is the middle of three vesicles that arise from the neural tube that forms the brain of developing animals. ... The red nucleus is a structure in the rostral midbrain involved in motor coordination. ... The thalamus (from Greek θάλαμος = bedroom, chamber, IPA= /ˈθæləməs/) is a pair and symmetric part of the brain. ... Medulla in general means the inner part, and derives from the Latin word for marrow. In medicine it is contrasted to the cortex. ... The red nucleus is a structure in the rostral midbrain involved in motor coordination. ... The thalamus (from Greek θάλαμος = bedroom, chamber, IPA= /ˈθæləməs/) is a pair and symmetric part of the brain. ... The premotor cortex is an area of motor cortex in the frontal lobe of the brain, located in front of the primary motor cortex and behind the prefrontal cortex. ... The middle cerebellar peduncles (brachia pontis) are composed entirely of centripetal fibers, which arise from the cells of the nuclei pontis of the opposite side and end in the cerebellar cortex; the fibers are arranged in three fasciculi, superior, inferior, and deep. ... The pontine nuclei are a part of the pons which store the memory of intention during motor activity. ... The neopallium (Latin for new mantle) is a part of the brain of mammals. ... Figure 1a: A human brain, with the cerebellum in purple. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ... It has been suggested that Equilibrioception be merged into this article or section. ... The spinocerebellar tract is a set of axonal fibers originating in the spinal cord and terminating in the cerebellum. ... This article does not cite its references or sources. ... In anatomy, the olivary bodies or simply olives (Latin oliva) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. ... ... The nuclei of the vestibular nerve. ... For other uses, see Pons (disambiguation). ... Medulla in general means the inner part, and derives from the Latin word for marrow. In medicine it is contrasted to the cortex. ... The anatomical planes The anatomical position is a schematic convention for describing the relative morphology of the human body. ... The Spinal cord nested in the vertebral column. ...


Blood supply

Figure 7: The three major arteries of the cerebellum: the SCA, AICA, and PICA.

Three arteries supply blood to the cerebellum (Fig. 7): the superior cerebellar artery (SCA), anterior inferior cerebellar artery (AICA), and posterior inferior cerebellar artery (PICA). Image File history File links Diagram of cerebellum blood supply. ... Image File history File links Diagram of cerebellum blood supply. ... The superior cerebellar artery arises near the termination of the basilar. ... The anterior inferior cerebellar artery passes backward to be distributed to the anterior part of the under surface of the cerebellum, anastomosing with the posterior inferior cerebellar branch of the vertebral. ... The posterior inferior cerebellar artery (PICA) is one of the three main arterial blood supplies for the cerebellum. ...


Superior cerebellar artery

The SCA branches off the lateral portion of the basilar artery, just inferior to its bifurcation into the posterior cerebral artery. Here it wraps posteriorly around the pons (to which it also supplies blood) before reaching the cerebellum. The SCA supplies blood to most of the cerebellar cortex, the cerebellar nuclei, and the middle and superior cerebellar peduncles.


Anterior inferior cerebellar artery

The AICA branches off the lateral portion of the basilar artery, just superior to the junction of the vertebral arteries. From its origin, it branches along the inferior portion of the pons at the cerebellopontine angle before reaching the cerebellum. This artery supplies blood to the anterior portion of the inferior cerebellum, and to the facial (CN VII) and vestibulocochlear nerves (CN VIII). The facial nerve is the seventh (VII) of twelve paired cranial nerves. ... The vestibulocochlear nerve (also known as the auditory or acoustic nerve) is the eighth of twelve cranial nerves, and is responsible for transmitting sound and equilibrium (balance) information from the inner ear to the brain. ...


Obstruction of the AICA can cause paresis, paralysis, and loss of sensation in the face; it can also cause hearing impairment. Moreover, it could cause an infarct of the cerebellopontine angle. This could lead to hyperacusia (dysfunction of the stapedius muscle, innervated by CN VII) and vertigo (wrong interpretation from the vestibular semi-circular canal's endolymph acceleration caused by alteration of CN VIII). Paresis is a condition typified by partial loss of movement, or impaired movement. ... Paralysed redirects here. ... A hearing impairment or hearing loss is a full or partial decrease in the ability to detect or understand sounds. ... The facial nerve is the seventh (VII) of twelve paired cranial nerves. ... For other uses, see Vertigo. ... Endolymph is the fluid contained in the membranous labyrinth of the inner ear. ... The vestibulocochlear nerve (also known as the auditory or acoustic nerve) is the eighth of twelve cranial nerves, and is responsible for transmitting sound and equilibrium (balance) information from the inner ear to the brain. ...


Posterior inferior cerebellar artery

The PICA branches off the lateral portion of the vertebral arteries just inferior to their junction with the basilar artery. Before reaching the inferior surface of the cerebellum, the PICA sends branches into the medulla, supplying blood to several cranial nerve nuclei. In the cerebellum, the PICA supplies blood to the posterior inferior portion of the cerebellum, the inferior cerebellar peduncle, the nucleus ambiguus, the vagus motor nucleus, the spinal trigeminal nucleus, the solitary nucleus, and the vestibulocochlear nuclei. Cranial nerves are nerves which start directly from the brainstem instead of the spinal cord. ... The nucleus ambiguus (literally ambiguous nucleus) is a region of histologically disparate cells located just dorsal (posterior) to the inferior olivary nucleus in the lateral portion of the upper (rostral) medulla. ... The vagus nerve (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired cranial nerves, and is the only nerve that starts in the brainstem (within the medulla oblongata) and extends, through the jugular foramen, down below the head, to the abdomen. ... The trigeminal nerve is the fifth (V) cranial nerve, and carries sensory information from most of the face, as well as motor supply to the muscles of mastication (the muscles enabling chewing), tensor tympani (in the middle ear), and other muscles in the floor of the mouth, such as the... The solitary nucleus and tract are structures in the brainstem that carry and receive visceral sensation and taste from the facial (VII), glossopharyngeal (IX), vagus (X) cranial nerves, as well as the cranial part of the accessory nerve (XI). ... The vestibulocochlear nerve (also known as the auditory or acoustic nerve) is the eighth of twelve cranial nerves, and is responsible for transmitting sound and equilibrium (balance) information from the inner ear to the brain. ...


General Function

Functionally, the climbing fiber and the mossy fiber-granule cell-parallel fiber pathways are the two main types of afferents to the cerebellum as a whole and to the Purkinje cells in particular. [7][8] These afferent systems differ dramatically in their connectivity. The Purkinje cell and its climbing fiber afferent have a one-to-one relationship and the overall projection is organized to produce synchronous activation of specific groupings of Purkinje cells in a rostrocaudal orientation. The relationship between the Purkinje cell and the mossy fiber-parallel fiber system can be characterized as many-to-many. With the directionality being mediolateral orientation within the molecular layer i.e. at right angles to the Purkinje cell dendrites which are isoplanar . This article does not cite its references or sources. ... In neuroscience, the term fiber describes a bundle of axons projecting from one group of neurons in a specific area to another. ...


The climbing fiber system


Originates from the contralateral inferior olive. As a result of the electrical coupling between inferior olivary neurons, their dynamic decoupling via return inhibition from the cerebellar nuclei[9] and the topography of the olivocerebellar projection, this system generates synchronous (on a millisecond time scale) complex spike activation of Purkinje cells, in rostrocaudally oriented bands. These activity bands are about 250 µm wide in the mediolateral direction but can be several millimeters long in the rostrocaudal direction and extend down the walls of the cerebellar folia and across several lobules.[10] The moment–to–moment synchrony distribution of motor control is dynamically modulated by the inferior olive with the major role of the olivary afferents being to determine the pattern of "effective" electronic coupling between olivary neurons and thereby the distribution of synchronous complex spike activity across the cerebellar cortex. Changes in synchrony patterns are associated with movements made by animals performing a motor task.[11].[12] Indeed. The olivocerebellar system can be considered an electrically malleable substrate from which unique motor synergies can be sculpted.


The Mossy Fiber-Parallel fiber system


In contrast to the punctate nature of cerebellar activation by the olivocerebellar system, the mossy fiber-parallel fiber system provides a continuous and very delicate regulation of the excitability of the cerebellar nuclei, brought about by the tonic activation of simple spikes in Purkinje cells, which ultimately generates the fine control of movement known as motor coordination. The fact that the mossy fibers inform the cerebellar cortex of both ascending and descending messages to and from the motor centers in the spinal cord and brainstem gives us an idea of the ultimate role of the mossy fiber system: it informs the cortex of the place and rate of movement of limbs and puts the motor intentions generated by the brain into the context of the status of the body at the time the movement is to be executed. Moreover, through its effects on the inhibitory GABAergic cerebellar nuclear cells, which project back to the inferior olive, it helps shape the pattern of coupling among olivary cells and hence the synchrony distribution in the upcoming olivocerebellar discharge. The cerebellum (Latin: little brain) is a region of the brain that plays an important role in the integration of sensory perception and motor output. ...


The cerebellar Nuclei


The Purkinje cells are the only output of the cerebellar cortex and are inhibitory in nature[13] Their axons contact the cerebellar and Deiters vestibular nucleus as their only target. The activity of the cerebellar nuclei is regulated in three ways: (1) by excitatory input from collaterals of the cerebellar afferent systems, (2) by inhibitory inputs from Purkinje cells activated over the mossy fiber pathways, and (3) by inputs from Purkinje cells activated by the climbing fiber system


Overall Cerebellar Function


The output of the cerebellum (the cerebellar nuclei axons) proceed to generate the background activity that serves to set the overall tone and posture that gives the motor cortex the ability to execute movements on the basis of intention (the strategy of movement). In this context the cerebellum provides the tactics of the multiple muscle activation required to support such define movements. And so, while the motor brain determines where to move (executive imperative) the cerebellum implements its proper timing and modulates the force given to every motor command, as the coordination of movement is a non-continuous function.[14]


Dysfunction

Main article: Ataxia

Ataxia is a complex of symptoms, generally involving a lack of coordination, that is often found in disease processes affecting the cerebellum. To identify cerebellar problems, the neurological examination includes assessment of gait (a broad-based gait being indicative of ataxia), finger-pointing tests and assessment of posture.[1] Structural abnormalities of the cerebellum (hemorrhage, infarction, neoplasm, degeneration) may be identified on cross-sectional imaging. Magnetic resonance imaging is the modality of choice, as computed tomography is insufficiently sensitive for detecting structural abnormalities of the cerebellum.[15] For other uses, see Ataxia (disambiguation). ... The neurological examination is the physical examination of the nervous system. ... MRI redirects here. ... negron305 Cat scan redirects here. ...


Aging

A stereological study has found that human cerebellar white matter was reduced by 26% with age (over the age range 19–84).[16] The researchers of the study could detect no global loss of Purkinje or granule cells, however in the anterior lobe there was a significant loss of these cell types as well as a 30% volume loss. With magnetic resonance imaging a moderate volumetric reduction with age in vermis and the cerebellar hemisphere has be observed.[17] Stereology is a spatial version of sampling theory. ... White matter is one of the two main solid components of the central nervous system. ... Ageing or aging is the process of getting older. ... Figure 1a: A human brain, with the cerebellum in purple. ... MRI redirects here. ... Figure 1a: A human brain, with the cerebellum in purple. ...


An autoradiography study of the human cerebellum found an increasing binding of H-3-ketanserin with age.[18] (ketanserin binds primarily to the 5-HT2A neuroreceptor) The same research team found no significant correlation with age in their homogenate binding study. Somewhat in line with the autoradiography study a positron emission tomography study with the altanserin 5-HT2A receptor radioligand found a positive correlation between age and cerebellar nonspecific binding.[19] An autoradiograph is an image produced on a photographic film by the radiation from a radioactive substance. ... Molecular binding is a method of molecular interaction to bind together or separate two or more molecules, and is important in the development of new medical drugs and other chemicals. ... Ketanserin is a serotonin receptor antagonist. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... Image of a typical positron emission tomography (PET) facility Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three-dimensional image or map of functional processes in the body. ... A radioligand is a radioactive biochemical substance that is used to study the receptor systems of the brain. ...


Theories about cerebellar function

Two main theories address the function of the cerebellum, both dealing with motor coordination. One claims that the cerebellum functions as a regulator of the "timing of movements". This has emerged from studies of patients whose timed movements are disrupted.[20]


The second, "Tensor Network Theory" provides a mathematical model of transformation of sensory (covariant) space-time coordinates into motor (contravariant) coordinates by cerebellar neuronal networks.[21][22]


Like many controversies in the physical sciences, there is evidence supporting each of the above hypotheses. Studies of motor learning in the vestibulo-ocular reflex and eyeblink conditioning demonstrate that the timing and amplitude of learned movements are encoded by the cerebellum.[23] Many synaptic plasticity mechanisms have been found throughout the cerebellum. The Marr-Albus model mostly attributes motor learning to a single plasticity mechanism: the long-term depression of parallel fiber synapses. The Tensor Network Theory of sensorimotor transformations by the cerebellum has also been experimentally supported.[24][25] Figure 3 Three-neuron arc, during a head movement to the right. ... Eyeblink conditioning is a form of classical conditioning in which animals are trained to blink in response to a tone. ... It has been suggested that pulse amplitude be merged into this article or section. ... In neuroscience, synaptic plasticity is the ability of the connection, or synapse, between two neurons to change in strength. ... Long-term depression (LTD), in neurophysiology, is the weakening of a neuronal synapse that lasts from hours to days. ...


With the advent of more sophisticated neuroimaging techniques such as positron emission tomography (PET),[26] and fMRI,[27] numerous diverse functions are now at least partially attributed to the cerebellum. What was once thought to be primarily a motor/sensory integration region is now proving to be involved in many diverse cognitive functions. It has been suggested that this article or section be merged with functional neuroimaging. ... Image of a typical positron emission tomography (PET) facility Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three-dimensional image or map of functional processes in the body. ...


Cerebellar modeling

As mentioned in the preceding section, there have been many attempts to model the cerebellar function.[28] The insights provided by the models have also led to extrapolations in the domains of artificial intelligence methodologies, especially neural networks. Some of the notable achievements have been Cerebellatron ,[29] Cerebellar Model Associative Memory or CMAC networks, and SpikeFORCE for robotic movement control,[30] and "Tensor Network Theory".[31] A mathematical model is an abstract model that uses mathematical language to describe the behaviour of a system. ... AI redirects here. ... A neural network is an interconnected group of neurons. ...


Additional images

See also

For other uses, see Brain (disambiguation). ... A diagram showing the CNS: 1. ... // medulla oblongata medullary pyramids pons paramedian pontine reticular formation fourth ventricle cerebellum cerebellar vermis cerebellar hemispheres anterior lobe posterior lobe flocculonodular lobe cerebellar nuclei fastigial nucleus globose nucleus emboliform nucleus dentate nucleus tectum inferior colliculi superior colliculi mesencephalic duct (cerebral aqueduct, Aqueduct of Sylvius) cerebral peduncle midbrain tegmentum ventral tegmental...

External links

Internet Archive headquarters is in the Presidio, a former US military base in San Francisco. ... Sather tower (the Campanile) looking out over the San Francisco Bay and Mount Tamalpais. ... Washington University redirects here. ... Screenshot of About. ... BrainMaps is an NIH-funded interactive zoomable high-resolution digital brain atlas and virtual microscope that is based on more than 10 million megapixels (30 terabytes) of scanned images of serial sections of both primate and non-primate brains and that is integrated with a high-speed database for querying... Website http://www. ...

Further reading

  • Ito M. Cerebellum and Neural Control. New York: Raven Press; 1984. ISBN 0-89004-106-7
  • Kandel ER, Schwartz JH, Jessell TM. Principles of Neural Science, 4th ed. McGraw-Hill, New York (2000). ISBN 0-8385-7701-6
  • Llinás, R, Sotelo C. The Cerebellum Revisited. New York: Springer; 1992. ISBN 0-387-97693-0
  • Parent A, Carpenter MB. Carpenter's Human Neuroanatomy. 9th ed. Philadelphia: Williams and Wilkins; 1995. ISBN 0-683-06752-4

Eric Richard Kandel (born November 7, 1929) is a psychiatrist, a neuroscientist and professor of biochemistry and biophysics at Columbia University. ... Principles of Nerual Science cover First published in 1981, Principles of Neural Science is a neuroscience textbook edited by Eric R. Kandel, James Schwartz, and Thomas Jessell. ...

References

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  2. ^ Rapp, Brenda (2001). The Handbook of Cognitive Neuropsychology: What Deficits Reveal about the Human Mind. Psychology Press, 481. ISBN 1841690449. 
  3. ^ The Brain From Top To Bottom
  4. ^ Muller F, O'Rahilly R (1990). "The human brain at stages 21–23, with particular reference to the cerebral cortical plate and to the development of the cerebellum". Anat Embryol (Berl) 182 (4): 375–400. PMID 2252222. 
  5. ^ Kingsley, R. E. (2000). Concise Text of Neuroscience, 2nd edition, Lippincott Williams and Wilkins. ISBN 0-683-30460-7. 
  6. ^ John K. Harting, Ph.D. The Global Cerebellum '97,[1] University of Wisconsin Medical School.
  7. ^ Ramon y Cajal. R. (1904). "La Textura del Sistema Nervioso del Hombre y los Vertebrados". Madrid: Moya.
  8. ^ Eccles J.C Ito, M and Szentagothai J. (1967). "The cerebellum as a neuronal machine". Springer Verlag
  9. ^ Llinás, R., Baker, R. and Sotelo, C. (1974). "Electrotonic coupling between neurons in cat inferior olive". J. Neurophysiol 37: 560-571.
  10. ^ Sugihara, I., Lang, E.J. and Llinás, R. (1993). "Uniform olivocerebellar conduction time underlies Purkinje cell complex spike synchronicity in the rat cerebellum". J. Physiol. Lond. 470: 243-271.
  11. ^ Welsh, J.P., Lang, E.J., Sugihara, I. and Llinás, R. (1995). "Dynamic organization of motor control within the olivocerebellar system". Nature 374: 453-457
  12. ^ Lang, E.J. (2001). "Organization of olivocerebellar activity in the absence of excitatory glutamatergic input". J. Neurosci. 21: 1663-1675
  13. ^ Ito, M., Yoshida, M. and Obata, K. (1964). "Monosynaptic inhibition of the intracerebellar nuclei induced from the cerebellar cortex". Experientia 20: 575-576.
  14. ^ Llinas R. (1991) " The noncontinuous nature of movement execution. In: Motor Control: Concepts and Issues, eds. D.R. Humphrey and H.J. Freund, John Wiley & Sons Ltd., Dahlem Konferenzen pp 223-242"
  15. ^ Gilman S (1998). "Imaging the brain. Second of two parts". N. Engl. J. Med. 338 (13): 889-96. PMID 9516225. 
  16. ^ Birgitte Bo Andersen, Hans Jørgen G. Gundersen, Bente Pakkenberg (2003). "Aging of the human cerebellum: A stereological study". The Journal of Comparative Neurology 466 (3): 356–365. doi:10.1002/cne.10884. 
  17. ^ Naftali Raz, Faith Gunning-Dixon, Denise Head, Adrienne Williamson & James D. Acker (June/July 2001). "Age and Sex Differences in the Cerebellum and the Ventral Pons: A Prospective MR Study of Healty Adults". AJNR American Journal of Neuroradiology 22: 1161–1167. 
  18. ^ Sharon L. Eastwood, Philip W. J. Burnet, Rebecca Gittins, Kate Baker, Paul J. Harrison (November 2001). "Expression of 5-HT2A receptors in the human cerebellum and alterations in schizophrenia". Synapse 42 (2): 104–114. doi:10.1002/syn.1106. 
  19. ^ K. H. Adams, Lars H. Pinborg, Claus Svarer, S. G. Hasselbalch, Søren Holm, S. Haugbøl, K. Madsen, Vibe G. Frøkjaer, L. Martiny, Olaf B. Paulson, Gitte Moos Knudsen (March 2004). "A database of [18F]-altanserin binding to 5-HT2A receptors in normal volunteers: normative data and relationship to physiological and demographic variables". Neuroimage 21 (3): 1105–1113. PMID 15006678. 
  20. ^ Ivry RB, Keele SW, Diener HC (1988). "Dissociation of the lateral and medial cerebellum in movement timing and movement execution". Exp Brain Res 73 (1): 167-80. PMID 3208855. 
  21. ^ Pellionisz, A., Llinás, R. (1980). "Tensorial Approach To The Geometry Of Brain Function: Cerebellar Coordination Via A Metric Tensor". Neuroscience 5: 1125—-1136. 
  22. ^ Pellionisz, A., Llinás, R. (1985). "Tensor Network Theory Of The Metaorganization Of Functional Geometries In The Central Nervous System". Neuroscience 16 (2): 245–273. 
  23. ^ Boyden ES, Katoh A, Raymond JL (2004). "Cerebellum-dependent learning: the role of multiple plasticity mechanisms". Annu Rev Neurosci 27: 581–609. PMID 15217344. 
  24. ^ Pellionisz A, Llinas R (1982). "Space-time representation in the brain. the cerebellum as a predictive space-time metric tensor". Neuroscience 7 (12): 2949–70. PMID 7162624. 
  25. ^ Gielen CC, van Zuylen EJ (1986). "Coordination of arm muscles during flexion and supination: application of the tensor analysis approach". Neuroscience 17 (3): 527-39. PMID 3703248. 
  26. ^ Obayashi S (2004). "Possible mechanism for transfer of motor skill learning: implication of the cerebellum". Cerebellum 3 (4): 204-11. PMID 15686098. 
  27. ^ Kim SG, Ugurbil K, Strick PL (1994). "Activation of a cerebellar output nucleus during cognitive processing". Science 265 (5174): 949-51. PMID 8052851. 
  28. ^ Pellionisz, A (1986). "David Marr's Theory of the Cerebellar Cortex: A Model in Brain Theory for the 'Galilean Combination of Simplification, Unification and Mathematization'", in Palm G., & Aertsen, A.: Brain Theory. Springer Verlag, 253–257. 
  29. ^ Dr Evor L. Hines. Intelligent Systems Engineering - Major Characteristics of Expert Systems and Artificial Neural Networks. Intelligent Systems Engineering (ES3770) Lecture Notes. Retrieved on 2006-03-28.
  30. ^ SpikeFORCE: Real-time Spiking Networks for Robot Control (PDF). Retrieved on 2006-03-28.
  31. ^ Pellionisz, András J.. "Tensor Network Theory of the Central Nervous System", in George Adelman: Encyclopedia of Neuroscience, II, Birkhauser, 1196–1198. 
Figure 5: Microcircuitry of the cerebellum. ... This article does not cite its references or sources. ... Figure 1a: A human brain, with the cerebellum in purple. ... Figure 1a: A human brain, with the cerebellum in purple. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... Figure 1a: A human brain, with the cerebellum in purple. ... Figure 1a: A human brain, with the cerebellum in purple. ... Figure 1a: A human brain, with the cerebellum in purple. ... The middle cerebellar peduncles (brachia pontis) are composed entirely of centripetal fibers, which arise from the cells of the nuclei pontis of the opposite side and end in the cerebellar cortex; the fibers are arranged in three fasciculi, superior, inferior, and deep. ... The superior cerebellar peduncles (brachia conjunctiva), two in number, emerge from the upper and medial part of the white substance of the hemispheres and are placed under cover of the upper part of the cerebellum. ...

  Results from FactBites:
 
Cerebellum - Psychology Wiki (4026 words)
The cerebellum is located in the inferior posterior portion of the head (the hindbrain), directly dorsal to the brainstem and pons, inferior to the occipital lobe (Figs.
The cerebellum arises from two rhombomeres located in the alar (dorsal, or upper) plate of the neural tube, a structure that eventually forms the brain and spinal cord.
In the cerebellum, the PICA supplies blood to the posterior inferior portion of the cerebellum, the inferior cerebellar peduncle, the nucleus ambiguus, the vagus motor nucleus, the spinal trigeminal nucleus, the solitary nucleus, and the vestibulocochlear nuclei.
Cerebellum - Wikipedia, the free encyclopedia (4093 words)
The cerebellum is located in the inferior posterior portion of the head (the hindbrain), directly dorsal to the brainstem and pons, inferior to the occipital lobe (Figs.
The cerebellum arises from two rhombomeres located in the alar (dorsal, or upper) plate of the neural tube, a structure that eventually forms the brain and spinal cord.
In the cerebellum, the PICA supplies blood to the posterior inferior portion of the cerebellum, the inferior cerebellar peduncle, the nucleus ambiguus, the vagus motor nucleus, the spinal trigeminal nucleus, the solitary nucleus, and the vestibulocochlear nuclei.
  More results at FactBites »

 
 

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