what is the major function of the cerebellum
motor control
608114
Cerebellum The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language as well as in regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to coordination, precision, and accurate timing: it receives
Cerebellum
130685
but more recently with speech and cognition. The great apes, including hominids, had a more pronounced cerebellum relative to the neocortex than other primates. It has been suggested that because of its function of sensory-motor control and learning complex muscular actions, the cerebellum may have underpinned human technological adaptations, including the preconditions of speech. The immediate survival advantage of encephalization is difficult to discern, as the major brain changes from "Homo erectus" to "Homo heidelbergensis" were not accompanied by major changes in technology. It has been suggested that the changes were mainly social and behavioural, including increased empathic abilities, increases
Human evolution
14948266
completely lose motor control in arms and legs or experience dysarthria (poor speech articulation), as patients with episodic ataxia do. The disturbances to vestibular function during periodic attacks are the primary distinction between vestibulocerebellar syndrome and other similar neurological syndromes. These conditions do not consistently cause the symptoms of dizziness and ocular impairment that have been localized to the vestibulocerebellum, leading researchers to characterize veistibulocerebellar syndrome as a distinct disorder. Vestibulocerebellar syndrome is caused by a failure in the function of the flocculus of the vestibulocerebellum, one of the three main divisions of the cerebellum. Generally, the cerebellum is responsible
Vestibulocerebellar syndrome
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the key finding that damage to the cerebellum results in motor disturbances. Jean Pierre Flourens in the first half of the 19th century carried out detailed experimental work, which revealed that animals with cerebellar damage can still move, but with a loss of coordination (strange movements, awkward gait, and muscular weakness), and that recovery after the lesion can be nearly complete unless the lesion is very extensive. By the beginning of the 20th century, it was widely accepted that the primary function of the cerebellum relates to motor control; the first half of the 20th century produced several detailed descriptions
Cerebellum
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cerebellum have come from examining the consequences of damage to it. Animals and humans with cerebellar dysfunction show, above all, problems with motor control, on the same side of the body as the damaged part of the cerebellum. They continue to be able to generate motor activity but lose precision, producing erratic, uncoordinated, or incorrectly timed movements. A standard test of cerebellar function is to reach with the tip of the finger for a target at arm's length: A healthy person will move the fingertip in a rapid straight trajectory, whereas a person with cerebellar damage will reach slowly and
Cerebellum
608114
Cerebellum The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language as well as in regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to coordination, precision, and accurate timing: it receives
Cerebellum
3791839
sclerosis) usually damage many different sectors of the nervous system. Ataxic dysarthria is an acquired neurological and sensorimotor speech deficit. It is a common diagnosis among the clinical spectrum of ataxic disorders. Since regulation of skilled movements is a primary function of the cerebellum, damage to the superior cerebellum and the superior cerebellar peduncle is believed to produce this form of dysarthria in ataxic patients. Growing evidence supports the likelihood of cerebellar involvement specifically affecting speech motor programming and execution pathways, producing the characteristic features associated with ataxic dysarthria. This link to speech motor control can explain the abnormalities in
Dysarthria
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and the role played in normal cerebellar function). From the phylogenetically oldest to the newest, the three parts are: 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. As explained in more detail in the Function section, the cerebellum differs from most other brain areas in that the flow of neural signals through it is almost entirely unidirectional: there are virtually no backward connections between its neuronal elements. Thus the most logical way
Anatomy of the cerebellum
608155
erratically, with many mid-course corrections. Deficits in non-motor functions are more difficult to detect. Thus, the general conclusion reached decades ago is that the basic function of the cerebellum is to calibrate the detailed form of a movement, not to initiate movements or to decide which movements to execute. Prior to the 1990s the function of the cerebellum was almost universally believed to be purely motor-related, but newer findings have brought that view into question. Functional imaging studies have shown cerebellar activation in relation to language, attention, and mental imagery; correlation studies have shown interactions between the cerebellum and non-motor
Cerebellum
14085009
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. Anatomy of the cerebellum The anatomy of the cerebellum can be viewed at three levels. At the level of gross anatomy, the cerebellum consists of a tightly folded and crumpled layer of cortex, with white matter underneath, several deep nuclei embedded in the white matter, and a fluid-filled ventricle in the middle. At the intermediate level,
Anatomy of the cerebellum
608186
the electrosensory system goes to the dorsal octavolateral nucleus, which also has a cerebellum-like structure. In ray-finned fishes (by far the largest group), the optic tectum has a layer—the marginal layer—that is cerebellum-like. All of these cerebellum-like structures appear to be primarily sensory-related rather than motor-related. All of them have granule cells that give rise to parallel fibers that connect to Purkinje-like neurons with modifiable synapses, but none have climbing fibers comparable to those of the cerebellum—instead they receive direct input from peripheral sensory organs. None has a demonstrated function, but the most influential speculation is that they serve to
Cerebellum
6445473
and the motor skills to function together. If this shift is repeated the flocculus essentially trains the brain to fully readjust to this repeated stimuli. Constituted by two disjointed-shaped lobes, the flocculus is positioned within the lowest level of the cerebellum. There are three main subdivisions in the cerebellum and the flocculus is contained within the most primitive the vestibulocerebellum. Its lobes are linked through a circuit of neurons connecting to the vermis, the medial structure in the cerebellum. Extensions leave the base of the follucular's lobes which then connect to the spinal cord. The cerebellum, which houses the flocculus,
Flocculus (cerebellar)
608164
the cerebellum have made it a fertile ground for theorizing—there are perhaps more theories of the function of the cerebellum than of any other part of the brain. The most basic distinction among them is between "learning theories" and "performance theories"—that is, theories that make use of synaptic plasticity within the cerebellum to account for its role in learning, versus theories that account for aspects of ongoing behavior on the basis of cerebellar signal processing. Several theories of both types have been formulated as mathematical models and simulated using computers. Perhaps the earliest "performance" theory was the "delay line" hypothesis
Cerebellum
608156
areas of the cerebral cortex; and a variety of non-motor symptoms have been recognized in people with damage that appears to be confined to the cerebellum. In particular, the cerebellar cognitive affective syndrome or Schmahmann's syndrome has been described in adults and children. Estimates based on functional mapping of the cerebellum using functional MRI suggest that more than half of the cerebellar cortex is interconnected with association zones of the cerebral cortex. Kenji Doya has argued that the cerebellum's function is best understood not in terms of the behaviors it affects, but the neural computations it performs; the cerebellum consists
Cerebellum
608124
spinal cord and the tegmentum. Output from the inferior peduncle is via efferent fibers to the vestibular nuclei and the reticular formation. The whole of the cerebellum receives modulatory input from the inferior olivary nucleus via the inferior cerebellar peduncle. Based on the surface appearance, three lobes can be distinguished within the cerebellum: the anterior lobe (above the primary fissure), the posterior lobe (below the primary fissure), and the flocculonodular lobe (below the posterior fissure). These lobes divide the cerebellum from rostral to caudal (in humans, top to bottom). In terms of function, however, there is a more important distinction
Cerebellum
608188
and Herophilus (quoted in Galen) called it the παρεγκεφαλίς ("paregkephalis"), as opposed to the ἐγκέφαλος ("egkephalos") or brain proper. Galen's extensive description is the earliest that survives. He speculated that the cerebellum was the source of motor nerves. Further significant developments did not come until the Renaissance. Vesalius discussed the cerebellum briefly, and the anatomy was described more thoroughly by Thomas Willis in 1664. More anatomical work was done during the 18th century, but it was not until early in the 19th century that the first insights into the function of the cerebellum were obtained. Luigi Rolando in 1809 established
Cerebellum
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larger in reptiles, considerably larger in birds, and larger yet in mammals. The large paired and convoluted lobes found in humans are typical of mammals, but the cerebellum is, in general, a single median lobe in other groups, and is either smooth or only slightly grooved. In mammals, the neocerebellum is the major part of the cerebellum by mass, but, in other vertebrates, it is typically the spinocerebellum. The cerebellum of cartilaginous and bony fishes is extraordinarily large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not
Cerebellum
608143
cell (a complex spike). The contrast between parallel fiber and climbing fiber inputs to Purkinje cells (over 100,000 of one type versus exactly one of the other type) is perhaps the most provocative feature of cerebellar anatomy, and has motivated much of the theorizing. In fact, the function of climbing fibers is the most controversial topic concerning the cerebellum. There are two schools of thought, one following Marr and Albus in holding that climbing fiber input serves primarily as a teaching signal, the other holding that its function is to shape cerebellar output directly. Both views have been defended in
Cerebellum
16180882
has been shown that white matter abnormalities are relatively confined to the cerebrum while avoiding the cerebellum and many of the major fiber tracts of the nervous system. The exception is the corticospinal tracts(pyramidal tracts) in the brainstem and sometimes spinal cord. The brain pathology of HDLS resembles that of Nasu-Hakola disease (polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy). Research as of 2012 includes investigations of microglial function. This work would further clarify whether the disease is primarily a defect in microglia function. For such a study, microglial cells from HDLS kindred can be cultured from autopsy brain and analyzed in
Hereditary diffuse leukoencephalopathy with spheroids
14085005
major part of the cerebellum by mass, but in other vertebrates, it is typically the spinocerebellum. In amphibians, lampreys, and hagfish the cerebellum is little developed; in the latter two groups it is barely distinguishable from the brain-stem. Although the spinocerebellum is present in these groups, the primary structures are small paired nuclei corresponding to the vestibulocerebellum. The cerebellum follows the general groups-of-three pattern found in anatomy, with three major input and output cerebellar peduncles (fiber bundles). These are the superior (brachium conjunctivum), middle (brachium pontis), and inferior (restiform and juxtarestiform bodies) cerebellar peduncles. There are three sources of input
Anatomy of the cerebellum
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The cerebellum sends thalamocortical projections and in addition may also send connections from the thalamus to association areas serving cognitive and affective functions. It is mostly separated from the pallidothalamic tracts. It can play a role in mediating symptoms in hereditary dystonia. The term "cerebellothalamocortical pathway" is used to indicate termination in the cerebral cortex. The cerebellothalamic tract transmits information from the cerebellum to the thalamus via neural impulses for the sensory systems. Motor adaptation is primarily a function of the cerebellothalamic fiber pathway. The cerebellum oversees modification of routine motor programs in response to changes in the environment (e.g.
Cerebellothalamic tract
91130
involved in both arousal and alertness. The cerebellum lies behind the pons. The cerebellum is composed of several dividing fissures and lobes. Its function includes the control of posture, and the coordination of movements of parts of the body, including the eyes and head as well as the limbs. Further it is involved in motion that has been learned and perfected though practice, and will adapt to new learned movements. Despite its previous classification as a motor structure, the cerebellum also displays connections to areas of the cerebral cortex involved in language as well as cognitive functions. These connections have
Central nervous system
19188768
Glutamate (neurotransmitter) In neuroscience, glutamate refers to the anion of glutamic acid in its role as a neurotransmitter: a chemical that nerve cells use to send signals to other cells. It is by a wide margin the most abundant neurotransmitter in the vertebrate nervous system. It is used by every major excitatory function in the vertebrate brain, accounting in total for well over 90% of the synaptic connections in the human brain. It also serves as the primary neurotransmitter for some localized brain regions, such as cerebellum granule cells. Biochemical receptors for glutamate fall into three major classes, known as
Glutamate (neurotransmitter)
16169583
of the cerebellum is responsible for emotional regulation. The deep nuclei of the cerebellum also have specific functions. The interpositus nucleus is involved with motor function, the dentate nucleus with cognitive functions, and the fastigial nucleus with limbic functions. It has been shown that phylogenetically the dentate nuclei developed with the association areas of the frontal cortex, supporting the view that the dentate nucleus is responsible for cognitive functions. There have been studies that show laterality effects of cerebellar damage with relation to CCAS. Language in the cerebellum seems to be contralateral to the dominant language hemisphere in the frontal
Cerebellar cognitive affective syndrome
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Cerebellar cognitive affective syndrome Cerebellar cognitive affective syndrome (CCAS), also called "Schmahmann's syndrome" is a condition that follows from lesions (damage) to the cerebellum of the brain. It refers to a constellation of deficits in the cognitive domains of executive function, spatial cognition, language, and affect resulting from damage to the cerebellum. Impairments of executive function include problems with planning, set-shifting, abstract reasoning, verbal fluency, and working memory, and there is often perseveration, distractibility and inattention. Language problems include dysprosodia, agrammatism and mild anomia. Deficits in spatial cognition produce visual–spatial disorganization and impaired visual–spatial memory. Personality changes manifest as blunting
Cerebellar cognitive affective syndrome
9255849
Mossy fiber (cerebellum) Mossy fibers are one of the major inputs to cerebellum. There are many sources of this pathway, the largest of which is the cerebral cortex, which sends input to the cerebellum via the pontocerebellar pathway. Other contributors include the vestibular nerve and nuclei, the spinal cord, the reticular formation, and feedback from deep cerebellar nuclei. Axons enter the cerebellum via the middle and inferior cerebellar peduncles, where some branch to make contact with deep cerebellar nuclei. They ascend into the white matter of the cerebellum, where each axon branches to innervate granule cells in several cerebellar folia.
Mossy fiber (cerebellum)
1669157
and stress on the spinal cord and can lead to a worsening of associated paralysis, scoliosis, back pain, and worsening bowel and/or bladder function. Many individuals with spina bifida have an associated abnormality of the cerebellum, called the Arnold Chiari II malformation. In affected individuals, the back portion of the brain is displaced from the back of the skull down into the upper neck. In about 90% of the people with myelomeningocele, hydrocephalus also occurs because the displaced cerebellum interferes with the normal flow of cerebrospinal fluid, causing an excess of the fluid to accumulate. In fact, the cerebellum also
Spina bifida
9255851
input from a single mossy fiber axon will influence processing in a very large number of Purkinje cells. Mossy fiber (cerebellum) Mossy fibers are one of the major inputs to cerebellum. There are many sources of this pathway, the largest of which is the cerebral cortex, which sends input to the cerebellum via the pontocerebellar pathway. Other contributors include the vestibular nerve and nuclei, the spinal cord, the reticular formation, and feedback from deep cerebellar nuclei. Axons enter the cerebellum via the middle and inferior cerebellar peduncles, where some branch to make contact with deep cerebellar nuclei. They ascend into
Mossy fiber (cerebellum)
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of the clinical symptoms associated with cerebellar disease in humans. The name "cerebellum" is a diminutive of "cerebrum" (brain); it can be translated literally as "little brain". The Latin name is a direct translation of the Ancient Greek παρεγκεφαλίς ("paregkephalis"), which was used in the works of Aristotle, the first known writer to describe the structure. No other name is used in the English-language literature, but historically a variety of Greek or Latin-derived names have been used, including "cerebrum parvum", "encephalion", "encranion", "cerebrum posterius", and "parencephalis". Cerebellum The cerebellum (Latin for "little brain") is a major feature of the hindbrain
Cerebellum
608158
as predictive action selection based on "internal models" of the environment or a device for supervised learning, in contrast to the basal ganglia, which perform reinforcement learning, and the cerebral cortex, which performs unsupervised learning. The comparative simplicity and regularity of the cerebellar anatomy led to an early hope that it might imply a similar simplicity of computational function, as expressed in one of the first books on cerebellar electrophysiology, "The Cerebellum as a Neuronal Machine" by John C. Eccles, Masao Ito, and János Szentágothai. Although a full understanding of cerebellar function has remained elusive, at least four principles have
Cerebellum
11347732
to be a promising therapeutic target in treating cancer. IDH3α is also implicated in psychiatric disorders. In particular, IDH3α expression in the cerebellum is observed to be significantly lower for bipolar disorder, major depressive disorder, and schizophrenia. The abnormal IDH3α levels may disrupt mitochondrial function and contribute to the pathogenesis of these disorders. IDH3A Isocitrate dehydrogenase [NAD] subunit alpha, mitochondrial (IDH3α) is an enzyme that in humans is encoded by the "IDH3A" gene. IDH3 is one of three isocitrate dehydrogenase isozymes, the other two being IDH1 and IDH2, and encoded by one of five isocitrate dehydrogenase genes, which are "IDH1",
IDH3A
7306859
similar to that of the cerebellum, a concept that currently is important in theories of DCN function. Thus, the DCN is thought to be involved with more complex auditory processing, rather than merely transferring information. The pyramidal cells or giant cells are a major cell grouping of the DCN. These cells are the target of two different input systems. The first system arises from the auditory nerve, and carries acoustic information. The second set of inputs is relayed through a set of small granule cells in the cochlear nucleus. There are also a great number of neighbouring cartwheel cells. The
Dorsal cochlear nucleus
15447882
role in standing or walking balance. The abdominal organs also contain receptors that provide geocentric information. "Roll-tilt" tests in which a subject's body is mechanically moved can be used to test for geocentric reference frame function. The righting reflex can be described as a three-neuron arc system composed of primary vestibular neurons, vestibular nuclei neurons, and target motorneurons. Input from the vestibular system is received by sensory receptors in the hair cells of the semicircular canals and the otoliths, which are processed in the vestibular nuclei. The cerebellum is also active at this time for processing of what is called
Righting reflex
8327
well developed than that of reptiles, birds and mammals but is similar in morphology and function to that of a fish. It is believed amphibians are capable of perceiving pain. The brain consists of equal parts, cerebrum, midbrain and cerebellum. Various parts of the cerebrum process sensory input, such as smell in the olfactory lobe and sight in the optic lobe, and it is additionally the centre of behaviour and learning. The cerebellum is the center of muscular coordination and the medulla oblongata controls some organ functions including heartbeat and respiration. The brain sends signals through the spinal cord and
Amphibian
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ataxia is often associated with damage to the frontopontocerebellar tract (Arnold's bundle) that connects the frontal lobe to the cerebellum. This pathway normally sends information from the cortical regions to the cerebellum, particularly information used to initiate planned movement. Many neurologists describe frontal lobe ataxia as really an apraxia, in which voluntary control of initiating movement is greatly hindered, but normal movement is present when elicited involuntarily or reflexively. This indicates that cerebellar function is intact and that the presented symptoms of Bruns apraxia are due to damage located within frontal lobe regions and pathways leading from there to the
Bruns apraxia
3549562
gait, such as Parkinson’s. The cerebellum plays a major role in motor coordination. Regulation of gait by the cerebellum is referred to as “error/correction,” because the cerebellum responds to abnormalities in posture in order to coordinate proper movement. The cerebellum sends signals to the cerebral cortex and the brain stem in response to sensory signals received from the spinal cord. Efferent signals from these regions go to the spinal cord where motor neurons are activated to regulate gait. There are multiple pathways within the spinal cord which play a role in regulating gait: The so-called natural gaits, in increasing order
Gait (human)
608185
DCN in a direction at right angles to the parallel fibers. The DCN is most highly developed in rodents and other small animals, and is considerably reduced in primates. Its function is not well understood; the most popular speculations relate it to spatial hearing in one way or another. Most species of fish and amphibians possess a lateral line system that senses pressure waves in water. One of the brain areas that receives primary input from the lateral line organ, the medial octavolateral nucleus, has a cerebellum-like structure, with granule cells and parallel fibers. In electrosensitive fish, the input from
Cerebellum
12751279
Dyschronometria Dyschronometria is a condition of cerebellar dysfunction in which an individual cannot accurately estimate the amount of time that has passed (i.e., distorted time perception). It is associated with cerebellar ataxia, when the cerebellum has been damaged and does not function to its fullest ability. Lesions to the cerebellum can cause dyssynergia, dysmetria, dysdiadochokinesia, dysarthria, and ataxia of stance and gait. Dyschronometria can result from autosomal dominant cerebellar ataxia (ADCA). Common signs of dyschronometria are often generic to cerebellar ataxia, including a lack of spatial awareness, poor short term memory, and inability to keep track of time. The defining
Dyschronometria
608173
very large. Congenital malformation, hereditary disorders, and acquired conditions can affect cerebellar structure and, consequently, cerebellar function. Unless the causative condition is reversible, the only possible treatment is to help people live with their problems. Visualization of the fetal cerebellum by ultrasound scan at 18 to 20 weeks of pregnancy can be used to screen for fetal neural tube defects with a sensitivity rate of up to 99%. In normal development, endogenous sonic hedgehog signaling stimulates rapid proliferation of cerebellar granule neuron progenitors (CGNPs) in the external granule layer (EGL). Cerebellar development occurs during late embryogenesis and the early postnatal
Cerebellum
20935374
Theory, it in fact holds three. These three separate brains work interdependently, interconnected by nerves, each of which operate differently with different capacities. The Reptilian Brain was referred to by MacLean as the ‘R Complex’ or the primitive brain. This is the oldest brain in the Triune Theory and anatomically is made up of the brain stem and the cerebellum. In reptiles, both the brain stem and cerebellum dominate and are the control centres for basic function. It has been found that these two parts of the brain are responsible for emotions such as paranoia, obsession and compulsion. Further, being
Neomammalian brain
2708423
producing the neurotransmitter, acetylcholine, which is then distributed widely throughout the brain. The basal forebrain, in particular the nucleus basalis, is considered to be the major cholinergic output of the central nervous system to the striatum and neocortex. The cerebellum is divided into an anterior lobe, a posterior lobe, and the flocculonodular lobe. The anterior and posterior lobes are connected in the middle by the vermis. The cerebellum has a much thinner outer cortex that is narrowly furrowed horizontally. Viewed from underneath between the two lobes is the third lobe the flocculonodular lobe. The cerebellum rests at the back of
Human brain
14084990
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. 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
Anatomy of the cerebellum
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of affect or disinhibited and inappropriate behavior. These cognitive impairments result in an overall lowering of intellectual function. CCAS challenges the traditional view of the cerebellum being responsible solely for regulation of motor functions. It is now thought that the cerebellum is responsible for monitoring both motor and nonmotor functions. The nonmotor deficits described in CCAS are believed to be caused by dysfunction in cerebellar connections to the cerebral cortex and limbic system. The CCAS has been described in both adults and children. The precise manifestations may vary on an individual basis, likely reflecting the precise location of the injury
Cerebellar cognitive affective syndrome
16169590
allow CCAS to be studied over a long period to see how CCAS affects development. It may be of interest to researchers to conduct more research on children with CCAS, as the survival rate of children with tumors in the cerebellum is increasing. Hopefully future research will bring new insights on CCAS and develop better treatments. Cerebellar cognitive affective syndrome Cerebellar cognitive affective syndrome (CCAS), also called "Schmahmann's syndrome" is a condition that follows from lesions (damage) to the cerebellum of the brain. It refers to a constellation of deficits in the cognitive domains of executive function, spatial cognition, language,
Cerebellar cognitive affective syndrome
4666250
close association with that of the nuclei of the vestibular cranial nerve and lateral line nerves, perhaps suggesting that this part of the cerebellum originated as a means of carrying out transformations of the coordinate system from input data of the vestibular organ and the lateral line organs. This suggests that the function of the cerebellum evolved as a mode of computing and representing an image relating to the position of the body in space. The cerebellar vermis evolved in conjunction with the hemispheres; this is seen in lampreys and higher vertebrates. In vertebrates, the cerebellar vermis develops between two
Cerebellar vermis
16169581
been shown to connect brainstem nuclei to the limbic system with implications for the function of the neurotransmitters serotonin, norepinephrine, and dopamine and the limbic system. The connection with the limbic system presumably underlies the affective symptoms of CCAS. It has been suggested that specific parts of the cerebellum are responsible for different functions. Mapping of the cerebellum has shown that sensorimotor, motor, and somatosensory information is processed in the anterior lobe, specifically in lobules V, VI, VIII A/B. The posterior lobe (notably cerebellar lobules VI and VII) is responsible for cognitive and emotional functions. Lobule VII includes the vermis
Cerebellar cognitive affective syndrome
11223470
movements is complicated by the additional expression of this receptor in the cerebellum and neocortex, two regions associated with the coordination and initiation of movement. Research suggests that anandamide is synthesized by Purkinje cells and acts on presynaptic receptors to inhibit glutamate release from granule cells or GABA release from the terminals of basket cells. In the neocortex, these receptors are concentrated on local interneurons in cerebral layers II-III and V-VI. Compared to rat brains, humans express more CB receptors in the cerebral cortex and amygdala and less in the cerebellum, which may help explain why motor function seems to
Cannabinoid receptor type 1
6277442
was no cure for dyslexia, Wynford began working with a team of researchers to investigate Harold Levinson's claim that the cerebellum is linked to the types of symptoms Susie was experiencing. Roy Rutherford, a friend of Wynford's, suggested that an underdeveloped cerebellum may be the cause of Susie's symptoms. The Dore programme was subsequently developed for Susie and, after she began to read and write, then made available to others. According to a video released by Dore, conditions such as dyslexia, developmental coordination disorder, ADD, Autism, Asperger syndrome and ADHD are linked to cerebellar function. Dore Program Practitioners believe that
Dore Programme
608144
great length in numerous publications. In the words of one review, "In trying to synthesize the various hypotheses on the function of the climbing fibers, one has the sense of looking at a drawing by Escher. Each point of view seems to account for a certain collection of findings, but when one attempts to put the different views together, a coherent picture of what the climbing fibers are doing does not appear. For the majority of researchers, the climbing fibers signal errors in motor performance, either in the usual manner of discharge frequency modulation or as a single announcement of
Cerebellum
12740011
The fighter jet's sensors fed information into the flight computer which in turn transformed that information into commands to control the plane's wing-flaps and ailerons to achieve a stable touchdown. This was synonymous to sensory inputs from the body being transformed into motor outputs by the cerebellum. The flight computer's calculations and behavior was modeled as a metric tensor taking the covariant sensor readings and transforming it into contravariant commands to control aircraft hardware. Tensor network theory Tensor network theory is a theory of brain function (particularly that of the cerebellum) that provides a mathematical model of the transformation of
Tensor network theory
12966672
of executive function have implicated the dorsolateral prefrontal cortex to be the primary site of cortical activation during these tasks. In addition, PET studies of patients with Parkinson's disease have suggested that tests of executive function are associated with abnormal function in the globus pallidus and appear to be the genuine result of basal ganglia damage. With substantial cognitive load, fMRI signals indicate a common network of frontal, parietal and occipital cortices, thalamus, and the cerebellum. This observation suggests that executive function is mediated by dynamic and flexible networks that are characterized using functional integration and effective connectivity analyses. The
Executive dysfunction
608167
strengthened, whereas Albus proposed that they would be weakened. Albus also formulated his version as a software algorithm he called a CMAC (Cerebellar Model Articulation Controller), which has been tested in a number of applications. The cerebellum is provided with blood from three paired major arteries: the superior cerebellar artery (SCA), the anterior inferior cerebellar artery (AICA), and the posterior inferior cerebellar artery (PICA). The SCA supplies the upper region of the cerebellum. It divides at the upper surface and branches into the pia mater where the branches anastomose with those of the anterior and posterior inferior cerebellar arteries. The
Cerebellum
17509816
on up again to the molecular layer, so that the Golgi cells are the target. According to Dieudonne, the Lugaro cell forms a major input to Golgi cells, and one Lugaro cell may contact up to 100 Golgi cells. Lugaro cell Lugaro cells are primary sensory interneurons of the cerebellum, that have an inhibitory function. They are fusiform, having a spindle shape that tapers at each end. They were first described by Ernesto Lugaro in the early 20th century. Lugaro cells are found just beneath the layer of Purkinje cells between the molecular layer and the granular layer. They have
Lugaro cell
17036201
centers of the brain. Lussana presents the case of a patient with loss of articulate speech as a result of an injury to the skull, and recovery of the same after the removal of bone fragments from that brain region. In 1853 he had the opportunity to attend along a young man with cancer of the cerebellum, publishing observations on the physiology of that organ ("The pathology of the cerebellum", Milan, 1856). Studying the origin of vertigo, Lussana shows the importance of the coordinating function of the brain, emphasizing how the sensations of the muscles, sight and hearing are necessary
Filippo Lussana
5836718
motor function, while the ventral region contains output channels involved in nonmotor function, such as cognition and visuospatial function. The dentate nucleus sends commands and information to the motor and premotor areas in the forebrain. Several pathological processes involve the dentate nucleus including metabolic, genetic, and neurodegenerative disorders, as well as some infections. Maple syrup urine disease (MSUD): An inherited disorder of amino acid metabolism in newborns, MSUD results in neurological deterioration. Myelin edema is seen in the cerebellum, including the dentate nucleus, brain stem, and corticospinal tracts. Leigh disease: Clinical and pathological symptoms usually appear in the first year
Dentate nucleus
608160
the cerebellum are derived from the ideas of David Marr and James Albus, who postulated that climbing fibers provide a teaching signal that induces synaptic modification in parallel fiber–Purkinje cell synapses. Marr assumed that climbing fiber input would cause synchronously activated parallel fiber inputs to be strengthened. Most subsequent cerebellar-learning models, however, have followed Albus in assuming that climbing fiber activity would be an error signal, and would cause synchronously activated parallel fiber inputs to be weakened. Some of these later models, such as the "Adaptive Filter" model of Fujita made attempts to understand cerebellar function in terms of optimal
Cerebellum
5836713
are comparable. All cerebral cortical areas that are targeted by the dentate project back on the cerebellum via efferents to Pontine nuclei, and cortical areas that do not project onto the cerebellum are not targets of dentate output. The motor domain in the dorsal portion of the dentate contains output channels that control both generation and control of movement, as well as neurons that innervate premotor areas in the frontal lobe. The nonmotor domain contains output channels involved in cognition and visuospatial function, and projections to the prefrontal and posterior parietal cortical areas within this region are clustered into distinct
Dentate nucleus
605605
aggregate field view, all areas of the brain participate in every mental function. Pierre Flourens, a French experimental psychologist, challenged the localizationist view by using animal experiments. He discovered that removing the cerebellum in rabbits and pigeons affected their sense of muscular coordination, and that all cognitive functions were disrupted in pigeons when the cerebral hemispheres were removed. From this he concluded that the cerebral cortex, cerebellum, and brainstem functioned together as a whole. His approach has been criticised on the basis that the tests were not sensitive enough to notice selective deficits had they been present. Perhaps the first
Cognitive neuroscience
14084991
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
Anatomy of the cerebellum
16169571
in the cerebellum. These investigators subsequently elaborated on the affective component of the CCAS, i.e., the neuropsychiatric phenomena. They reported that patients with injury isolated to the cerebellum may demonstrate distractibility, hyperactivity, impulsiveness, disinhibition, anxiety, ritualistic and stereotypical behaviors, illogical thought and lack of empathy, aggression, irritability, ruminative and obsessive behaviors, dysphoria and depression, tactile defensiveness and sensory overload, apathy, childlike behavior, and inability to comprehend social boundaries and assign ulterior motives. The CCAS can be recognized by the pattern of deficits involving executive function, visual-spatial cognition, linguistic performance and changes in emotion and personality. Underdiagnosis may reflect lack of
Cerebellar cognitive affective syndrome
18752079
PRP36 PRP36 (Proline Rich Protein 36) is an extracellular protein in "Homo sapiens" that is encoded by the PRR36 (Proline Rich Region 36) gene that contains a domain of unknown function, DUF4596, towards the C terminus of the protein. The function of PRP36 is unknown, but high gene expression has been observed in various regions of the brain such as the prefrontal cortex, cerebellum, and the amygdala. PRP36 has one alias: "Putative Uncharacterized Protein FLJ22184". The human PRR36 gene consists of 7 exons and is 5723 base pairs long. PRR36 is located on the short arm of human chromosome 19
PRP36
2318613
to give not only medical treatment to those mentally ill, but also provide with caretakers and comfortable living conditions. In 1755, Jean-Baptiste Le Roy began using electroconvulsive therapy for the mentally ill, a treatment still used today in specific cases. In 1760, Arne-Charles studied how different lesions in the cerebellum could affect motor movements. In 1776, studied the cerebellum intensely, and published a book solely based on its function and appearance. In 1784, Félix Vicq-d'Azyr, discovered a black colored structure in the midbrain. In 1791 Samuel Thomas von Sömmerring alluded to this structure, calling it the substantia nigra. In the
Neurophysiology
15272151
steps towards reptiles, but the development of hard-shelled external eggs replacing the amphibious water bound eggs is the defining feature of the class Reptilia and is what allowed these amphibians to fully leave water. Another major difference from amphibians is the increased brain size, more specifically, the enlarged cerebrum and cerebellum. Although their brain size is small when compared to birds and mammals, these enhancements prove vital in hunting strategies of reptiles. The increased size of these two regions of the brain allowed for improved motor skills and an increase in sensory development. The origin of the reptiles lies about
Evolution of reptiles
236941
have brain changes that cause confusion, speech difficulties, depression, decline in intellectual function, impaired judgement and impaired memory. If areas of the cerebellum are affected by seizures, it is common to see problems with speech, coordination, and balance in Lafora patients. For dogs that are affected with Lafora disease, common symptoms are rapid shuddering, shaking, or jerking of the canine's head backwards, high pitched vocalizations that could indicate the dog is panicking, seizures, and as the disease progresses dementia, blindness, and loss of balance. Lafora disease is an autosomal recessive disorder, caused by loss of function mutations in either laforin
Lafora disease
5817293
cortex → hippocampal formation. A photograph of the inferior medial view of the brain when dissected clearly shows the layout of the Papez circuit. Due to the location of the structures in the circuit, the resulting shape is a limbus. This is what drove MacLean to call the circuit the limbic system when he later modified the circuit. Various studies indicate that the Papez circuit is greatly influenced by the cerebellum and that perhaps the hippocampus is not the starting point of the circuit. Anatomically, this would make sense since the cerebellum is connected to the circuit with many fine
Papez circuit
9223432
Cerebellar model articulation controller The cerebellar model arithmetic computer (CMAC) is a type of neural network based on a model of the mammalian cerebellum. It is also known as the cerebellar model articulation controller. It is a type of associative memory. The CMAC was first proposed as a function modeler for robotic controllers by James Albus in 1975 (hence the name), but has been extensively used in reinforcement learning and also as for automated classification in the machine learning community. CMAC computes a function formula_1, where formula_2 is the number of input dimensions. The input space is divided up into
Cerebellar model articulation controller
18765923
connectivity. J Neurophys, 106: 2322-45. Buckner RL (2012) The serendipitous discovery of the brain’s default network. NeuroImage, 62: 1137-45. Buckner RL (2013) The cerebellum and cognitive function: 25 years of insight from anatomy and neuroimaging. Neuron, 80: 807-15. Randy Buckner Randy L. Buckner (born June 15, 1970) is an American neuroscientist and psychologist whose research focuses on understanding how large-scale brain circuits support mental function and how dysfunction arises in illness. Buckner is a Professor of Psychology and Neuroscience at Harvard University. He is affiliated with the Center for Brain Science and is Director of the Psychiatric Neuroimaging Research Division
Randy Buckner
10422668
commonly associated with P450 proteins, and is coupled with the PGRMC1 complex, EGFR, mTOR, caspases, and various ion channels. The sigma-2 receptor is found in several areas of the brain, including high densities in the cerebellum, motor cortex, hippocampus, and substantia nigra, though it shows no homology with other proteins present in brain tissue. It is also highly expressed in the lungs, liver, and kidneys. The sigma-2 receptor takes part in a number of normal-function roles, including cell proliferation, non-neuronal, and neuronal signaling. Much of sigma-2 receptor function relies on signaling cascades. The receptor's interaction with EGFR and PGRMC1 proteins
Sigma-2 receptor
2886201
cerebellum, and other regions of the brain. The lesions take on different forms, including areas of demyelination, spongiosis, gliosis, necrosis, and capillary proliferation. Demyelination is the loss of the myelin sheath around the axons of neurons, inhibiting their ability to communicate with other neurons. The brain stem is involved in maintaining basic life functions such as breathing, swallowing, and circulation; the basal ganglia and cerebellum control movement and balance. Damage to these areas therefore results in the major symptoms of Leigh syndrome—loss of control over functions controlled by these areas. The lactic acidosis sometimes associated with Leigh syndrome is caused
Leigh syndrome
7954683
type I in the heart, skeletal muscle and brain, as opposed to type II, which is mainly expressed in non-muscular tissues including the cerebrum, cerebellum, kidney, spleen, and aortic endothelial cells. The highest expression of VLDLR is found in the brain. Although VLDLR is found in almost all regions of the brain, its highest expression is restricted to the cortex and cerebellum. Here, the receptor can be found on resting or activated microglia that are associated with senile plaques and cortical neurons, neuroblasts, matrix cells, Cajal-Retzius cells, glioblasts, astrocytes, oligodendrocytes, and region-specific pyramidal neurons. Despite its major role in cholesterol
VLDL receptor
12740003
Tensor network theory Tensor network theory is a theory of brain function (particularly that of the cerebellum) that provides a mathematical model of the transformation of sensory space-time coordinates into motor coordinates and vice versa by cerebellar neuronal networks. The theory was developed by Andras Pellionisz and Rodolfo Llinas in the 1980s as a geometrization of brain function (especially of the central nervous system) using tensors. The mid-20th century saw a concerted movement to quantify and provide geometric models for various fields of science, including biology and physics. The geometrization of biology began in the 1950s in an effort to
Tensor network theory
608182
size while the cerebrum decreased in size With both the development and implementation of motor tasks, visual-spatial skills and learning taking place in the cerebellum, the growth of the cerebellum is thought to have some form of correlation to greater human cognitive abilities. The lateral hemispheres of the cerebellum are now 2.7 times greater in both humans and apes than they are in monkeys. These changes in the cerebellum size cannot be explained by greater muscle mass. They show that either the development of the cerebellum is tightly linked to that of the rest of the brain or that neural
Cerebellum
20074997
White cerebellum sign The white cerebellum sign, also known as reversal sign or dense cerebellum sign, is a radiological sign denoting the relatively white appearance of the cerebellum due to a generalized decrease in density of the supratentorial brain structures caused by extensive edema. White cerebellum sign can be associated with raised intracranial pressure that occurs due to anoxic or ischemic changes in the brain. It can be found in: Diffuse brain edema is the likely cause of this radiological change observed in CT or MRI. It was considered to indicate a bad prognosis. However, evidence suggests that it could
White cerebellum sign
608183
activities taking place in the cerebellum were important during Hominidae evolution. Due to the cerebellum's role in cognitive functions, the increase in its size may have played a role in cognitive expansion. Most vertebrate species have a cerebellum and one or more cerebellum-like structures, brain areas that resemble the cerebellum in terms of cytoarchitecture and neurochemistry. The only cerebellum-like structure found in mammals is the dorsal cochlear nucleus (DCN), one of the two primary sensory nuclei that receive input directly from the auditory nerve. The DCN is a layered structure, with the bottom layer containing granule cells similar to those
Cerebellum
20074998
be a non-specific indicator of diffuse brain edema which might not be as ominous as previously thought. White cerebellum sign The white cerebellum sign, also known as reversal sign or dense cerebellum sign, is a radiological sign denoting the relatively white appearance of the cerebellum due to a generalized decrease in density of the supratentorial brain structures caused by extensive edema. White cerebellum sign can be associated with raised intracranial pressure that occurs due to anoxic or ischemic changes in the brain. It can be found in: Diffuse brain edema is the likely cause of this radiological change observed in
White cerebellum sign
9872113
describes what something "does", not what its 'purpose' is. However, teleological language is often used by biologists as a shorthand way of describing function, even though its applicability is disputed. In contemporary philosophy of biology, there are three major accounts of function in the biological world: theories of causal role, selected effect, and goal contribution. Causal role theories of biological function trace their origin back to a 1975 paper by Robert Cummins. Cummins defines the functional role of a component of a system to be the causal effect that the component has on the larger containing system. For example, the
Function (biology)
4635987
target for each climbing fiber is a specific neuron in the cerebellum referred to as a Purkinje Cell. During development, there are multiple climbing fibers on a purkinje cell, however these are pruned off during postnatal development, thus leaving a mature purkinje cell with a single climbing fiber. There are three major components of the IO. Patient studies revealed the connection between the inferior olivary nucleus (ION) and the cerebellum. Lesions in the ION impair the ability to learn higher level motility, such as performing a perfect jumpshot. Further investigation of the neuroanatomy confirmed the intimate connection between the IO
Inferior olivary nucleus
608168
AICA supplies the front part of the undersurface of the cerebellum. The PICA arrives at the undersurface, where it divides into a medial branch and a lateral branch. The medial branch continues backward to the cerebellar notch between the two hemispheres of the cerebellum; while the lateral branch supplies the under surface of the cerebellum, as far as its lateral border, where it anastomoses with the AICA and the SCA. Damage to the cerebellum often causes motor-related symptoms, the details of which depend on the part of the cerebellum involved and how it is damaged. Damage to the flocculonodular lobe
Cerebellum
608119
"microzones" or "microcompartments". The cerebellum is located in the posterior cranial fossa. The fourth ventricle, pons and medulla are in front of the cerebellum. It is separated from the overlying cerebrum by a layer of leathery dura mater, the tentorium cerebelli; all of its connections with other parts of the brain travel through the pons. Anatomists classify the cerebellum as part of the metencephalon, which also includes the pons; the metencephalon is the upper part of the rhombencephalon or "hindbrain". Like the cerebral cortex, the cerebellum is divided into two hemispheres; it also contains a narrow midline zone (the vermis).
Cerebellum
2171938
shape of the cerebellum in different vertebrate species. In amphibians, lampreys, and hagfish, the cerebellum is little developed; in the latter two groups, it is barely distinguishable from the brain-stem. Although the spinocerebellum is present in these groups, the primary structures are small paired nuclei corresponding to the vestibulocerebellum. The cerebellum of cartilaginous and bony fishes is extraordinarily large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei. Instead, the primary targets of Purkinje cells are a distinct type of cell distributed
Fish anatomy
608178
of vertebrates, including fish, reptiles, birds, and mammals. There is also an analogous brain structure in cephalopods with well-developed brains, such as octopuses. This has been taken as evidence that the cerebellum performs functions important to all animal species with a brain. There is considerable variation in the size and shape of the cerebellum in different vertebrate species. In amphibians, it is little developed, and in lampreys, and hagfish, the cerebellum is barely distinguishable from the brain-stem. Although the spinocerebellum is present in these groups, the primary structures are small, paired-nuclei corresponding to the vestibulocerebellum. The cerebellum is a bit
Cerebellum
2077214
lost the function of flight. In contrast Darwin argued that the wings of emus would be definitely vestigial, as they appear to have no major extant function; however, function is a matter of degree, so judgements on what is a "major" function are arbitrary; the emu does seem to use its wings as organs of balance in running. Similarly, the ostrich uses its wings in displays and temperature control, though they are undoubtedly vestigial as structures for flight. Vestigial characters range from detrimental through neutral to favorable in terms of selection. Some may be of some limited utility to an
Vestigiality
608120
A set of large folds is, by convention, used to divide the overall structure into 10 smaller "lobules". Because of its large number of tiny granule cells, the cerebellum contains more neurons than the total from the rest of the brain, but takes up only 10% of the total brain volume. The number of neurons in the cerebellum is related to the number of neurons in the neocortex. There are about 3.6 times as many neurons in the cerebellum as in the neocortex, a ratio that is conserved across many different mammalian species. The unusual surface appearance of the cerebellum
Cerebellum
4635986
GABAα receptor make-up varies based on where the receptor localizes on the ION neuron. The reason for this spatial distribution is unknown. It has been proposed that the distinct populations of GABAα receptors allows for fine-tuned regulation within the ION. The inferior olivary nucleus (ION) has a distinct These lamina house the cell bodies of the olivocerebellar fibers. These neurons are the major input source for the cerebellum. Their axons are referred to as climbing fibers. These climbing fibers leave the ION medially through the hilum, cross the midline, and ascend into the cerebellum via the inferior cerebellar peduncle. The
Inferior olivary nucleus
11225542
Type 2 diabetes, the percentile rank relative to other transcripts decreases relative to normal cell function. The deletion of TP63, which mediates a wide variety of important body processes, also produces decreased GPR113 expression. In mice brains, the cerebellum and the olfactory bulb both show transcription of the GPR113 gene. Additionally, a study from the National Institute of Deafness and Other Communication Disorders has identified GPR113 expression to be highly restricted to a subset of taste receptor cells. This paper's conclusions, coupled with olfactory bulb expression levels, could provide an avenue for future research, potentially illuminating more about GPR113's function.
GPR113
7524962
persistent intention tremors are often caused by damage to certain regions of the brain. The most common cause of intention tremors is damage and/or degeneration in the cerebellum. The cerebellum is a part of the brain responsible for motor coordination, posture and balance. It is responsible for fine motor movements. When the cerebellum is damaged, a person may have difficulty executing a fine motor movement, such as attempting to touch one's nose with one's finger. One common way for the cerebellum to become damaged is through the development of cerebellar lesions. The most common site for cerebellar lesions that lead
Intention tremor
4635990
is tightly associated with the cerebellum, lesions in either the IO or the cerebellum results in degeneration in the other. There is little known about damage to the inferior olivary nucleus (IO) independent from the cerebellum. To date, the only known disorder which specifically targets the ION is an extremely rare form of degeneration called hypertrophic olivary degeneration (HOD). Although the ION is not often investigated on its own, degeneration in the ION has been identified in disorders that are typically associated with the cerebellum. These disorders include supranuclear palsy, Leigh disease, and SCA6, and there are several more. These
Inferior olivary nucleus
13675588
cells of the cerebellum. Among the five members of the CRMP family, CRMP-2 is the most highly expressed in the adult brain, especially in post-mitotic neurons of the olfactory system, cerebellum, and hippocampus. CRMP-3 mRNA is only expressed in the granular layer of the cerebellum, inferior olive, and dentate gyrus of the hippocampus. CRMP-4 is the least expressed protein of CRMP family and its expression is restricted to the olfactory bulb, hippocampus, and the internal granule layer (IGL) of the cerebellum. Lastly, CRMP-5 is expressed not only in post-mitotic neurons of the olfactory bulb, olfactory epithelium, and dentate gyrus of
Collapsin response mediator protein family
14085004
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. There is considerable variation in the size and shape of the cerebellum in different vertebrate species. It is generally largest in cartilaginous and bony fish, birds, and mammals, but somewhat smaller in reptiles. The large paired and convoluted lobes found in humans are typical of mammals, but the cerebellum is generally a single median lobe in other groups, and is either smooth or only slightly grooved. In mammals, the neocerebellum is the
Anatomy of the cerebellum
608172
a variant of Guillain–Barré syndrome. The human cerebellum changes with age. These changes may differ from those of other parts of the brain. The cerebellum is the youngest brain region (and body part) in centenarians according to an epigenetic biomarker of tissue age known as epigenetic clock: it is about 15 years younger than expected in a centenarian. Further, gene expression patterns in the human cerebellum show less age-related alteration than that in the cerebral cortex. Some studies have reported reductions in numbers of cells or volume of tissue, but the amount of data relating to this question is not
Cerebellum
18276864
been reported as of 1998. Agenesis of one half or another part of the cerebellum is more common than complete agenesis. Cerebellar agenesis can be caused by mutations in the PTF1A gene. Cerebellar agenesis Cerebellar agenesis is a rare condition in which a brain develops without the cerebellum. The cerebellum controls smooth movement, and when it does not develop, the rest of the brain must compensate, which it cannot do completely. The condition is not fatal on its own, but people born without a cerebellum experience severe developmental delays, language deficits, and neurological abnormalities. As children with cerebellar agenesis get
Cerebellar agenesis
608159
been identified as important: (1) feedforward processing, (2) divergence and convergence, (3) modularity, and (4) plasticity. There is considerable evidence that the cerebellum plays an essential role in some types of motor learning. The tasks where the cerebellum most clearly comes into play are those in which it is necessary to make fine adjustments to the way an action is performed. There has, however, been much dispute about whether learning takes place within the cerebellum itself, or whether it merely serves to provide signals that promote learning in other brain structures. Most theories that assign learning to the circuitry of
Cerebellum
10971868
placenta, cerebellum, and spleen; it is most commonly expressed in the thymus. The thymus is a lymphoid organ involved in the function of the immune system, where T cells mature. T cells are an important component to the adaptive immune system, because it is where the body adapts to foreign substances; this demonstrates TRPV2’s importance in the immune system. TRPV2 in mus musculus is also activated by hypo-osmolarity and cell stretching, indicating that TRPV2 plays a role in mechanotransduction in mice as well. In experiments with knockout mice (TRPV2KO mice), it was found that TRPV2 is expressed in brown adipocytes
TRPV2
16460377
of PCH. A child inheriting two damaged copies of the gene will be affected by PCH. Mutations in the genes that cause PCH produce faults in the production of chemicals, usually enzymes, that are required for the development of nerve cells (neurons) and for properly processing RNA, which is needed for any cell to function normally. The exact mechanism by which PCH affects the development of the cerebellum and pons is not well understood. Pontocerebellar hypoplasia is classified as follows: Pontine and cerebellar hypoplasia is also observed in certain phenotypes of X-linked mental retardation – so called MICPCH. Another gene
Pontocerebellar hypoplasia
608149
are, however, a number of respects in which the structure of the cerebellum is compartmentalized. There are large compartments that are generally known as "zones"; these can be divided into smaller compartments known as "microzones". The first indications of compartmental structure came from studies of the receptive fields of cells in various parts of the cerebellar cortex. Each body part maps to specific points in the cerebellum, but there are numerous repetitions of the basic map, forming an arrangement that has been called "fractured somatotopy". A clearer indication of compartmentalization is obtained by immunostaining the cerebellum for certain types of
Cerebellum
2708409
and association regions. Although the left and right hemispheres are broadly similar in shape and function, some functions are associated with one side, such as language in the left and visual-spatial ability in the right. The hemispheres are connected by commissural nerve tracts, the largest being the corpus callosum. The cerebrum is connected by the brainstem to the spinal cord. The brainstem consists of the midbrain, the pons, and the medulla oblongata. The cerebellum is connected to the brainstem by pairs of tracts. Within the cerebrum is the ventricular system, consisting of four interconnected ventricles in which cerebrospinal fluid is
Human brain
13364049
cell type. The highest levels are found in neuronal cells of the central nervous system. The amount of hydroxymethylcytosine increases with age, as shown in mouse hippocampus and cerebellum. The exact function of this nitrogen base is still not fully elucidated, but it is thought that it may regulate gene expression or prompt DNA demethylation. This hypothesis is supported by the fact that artificial DNA that contains 5-hydroxymethylcytosines (5hmC) can be converted into unmodified cytosines once introduced into mammalian cells. Moreover, 5hmC is highly enriched in primordial germ cells, where it apparently plays a role in global DNA demethylation. Additionally,
5-Hydroxymethylcytosine
7524964
an inability for those neurons to transmit signals. Because of this tight association with damage to the cerebellum, intention tremors are often referred to as cerebellar tremors. Intention tremors can also be caused as a result of damage to the brainstem or thalamus. Both of these structures are involved in the transmission of information between the cerebellum and the cerebral cortex, as well as between the cerebellum and the spinal cord, and then on to the motor neurons. When these become damaged, the relay system between the cerebellum and the muscle which it is trying to act upon is compromised,
Intention tremor
3959565
the brainstem and is very densely packed with neurons and neural connections. This part of the brain is involved in timing as well as movement. It assists in predicting events, especially in the formation, execution, and timing of conditioned responses. The cerebellum plays a very important role in all forms of kinesthetic learning and motor function. For a ballerina, it is important to be able to control their movements and time it exactly right for their routine. For a football player it is important to be able to regulate movement when running throwing, and being able to have control over
Kinesthetic learning
13789014
is large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei. Instead, the primary targets of Purkinje cells are a distinct type of cell distributed across the cerebellar cortex, a type not seen in mammals. The circuits in the cerebellum are similar across all classes of vertebrates, including fish, reptiles, birds, and mammals. There is also an analogous brain structure in cephalopods with well-developed brains, such as octopuses. This has been taken as evidence that the cerebellum performs functions important to all
Fish intelligence
11221862
the formation of gall stones and polyps. VIPR2 Vasoactive intestinal peptide receptor 2 also known as VPAC, is a G-protein coupled receptor that in humans is encoded by the "VIPR2" gene. VIPR2 is expressed in the uterus, prostate, smooth muscle of the gastrointestinal tract, seminal vesicles and skin, blood vessels and thymus. VIPR2 is also expressed in the cerebellum. Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating polypeptide (PACAP) are homologous peptides that function as neurotransmitters and neuroendocrine hormones. While the receptors for VIP (VIRP 1 and 2) and PACAP (ADCYAP1R1) share homology, they differ in their substrate specificities
VIPR2