|
Posterior Lobe Of Cerebellum
The posterior lobe of cerebellum or neocerebellum, is the portion of the cerebellum below the primary fissure. The posterior lobe is much larger than anterior lobe. The anterior lobe is separated from the posterior lobe by the primary fissure, and the posterolateral fissure separates flocculonodular lobe from the posterior lobe. Sometimes, the posterior lobe of cerebellum is called the neocerebellum since phylogenetically it is the newest part of the cerebellum. It plays an important role in fine motor coordination, specifically in the inhibition of involuntary movement via inhibitory neurotransmitters, especially GABA. The posterior lobe receives input mainly from the brainstem (i.e., reticular formation and inferior olivary nucleus The inferior olivary nucleus (ION), is a structure found in the medulla oblongata underneath the superior olivary nucleus.Gado, Thomas A. Woolsey; Joseph Hanaway; Mokhtar H. (2003). The brain atlas a visual guide to the human central nervous syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Fissure Of Cerebellum
The monticulus of the cerebellum is divided by the primary fissure (or preclival fissure) into an anterior, raised part, the culmen or summit, and a posterior sloped part, the clivus; the quadrangular lobule is similarly divided. Additional images File:Primary fissure of cerebellum -- animation.gif, Animation. Primary fissure shown in red. File:Primary fissure of cerebellum --- animation.gif, Close up animation. Primary fissure shown in red. File:Cerebellar lobes by Sanjoy Sanyal.webm, Dissection video (1 min 20 s). Demonstrating the three cerebellar lobes. "V-shaped fissure" is the primary fissure. See also * 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 ... References External links * https://web.archive.org/web/20080614064333/http://www.ib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Lobe Of Cerebellum
The anterior lobe of cerebellum is the portion of the cerebellum responsible for mediating unconscious proprioception. Inputs into the anterior lobe of the cerebellum are mainly from the spinal cord. It is sometimes equated to the "paleocerebellum". Clinical significance Anterior lobe syndrome When a person gets most of their calories from alcohol (chronic alcoholism) the anterior lobe can deteriorate due to malnutrition. This is known as anterior lobe syndrome, and it causes unsteady gait. Additional images File:Anterior lobe of cerebellum -- animation.gif, Animation. Anterior lobe shown in red. File:Anterior lobe of cerebellum --- animation.gif, Close up animation. Anterior lobe shown in red. File:Cerebellar lobes by Sanjoy Sanyal.webm, Dissection video (1 min 20 s). Demonstrating the three cerebellar lobes. References External links * NIF Search - Anterior Lobe of the Cerebellumvia the Neuroscience Information Framework The Neuroscience Information Framework is a r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 cognition, cognitive functions such as attention and language as well as emotion, emotional control such as 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 Motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in Fine motor skill, fine movement, Equilibrioception, equilibrium, Human positions, posture, and motor learning in humans. Anatomica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flocculonodular Lobe
The flocculonodular lobe (vestibulocerebellum) is a lobe of the cerebellum consisting of the nodule and the flocculus. The two flocculi are connected to the midline structure called the nodulus by thin pedicles. It is placed on the anteroinferior surface of cerebellum. This region of the cerebellum has important connections to the vestibular nuclei and uses information about head movement to influence eye movement. Lesions to this area can result in multiple deficits in visual tracking and oculomotor control (such as nystagmus and vertigo), integration of vestibular information for eye and head control, as well as control of axial muscles for balance. This lobe is also involved in the maintenance of balance equilibrium and muscle tone. The most common cause of damage to the flocculonodular lobe is medulloblastoma in childhood. References External links NIF Search - Flocculonodular lobevia the Neuroscience Information Framework The Neuroscience Information Framework is a rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetically
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fine Motor Coordination
Motor coordination is the orchestrated movement of multiple body parts as required to accomplish intended actions, like walking. This coordination is achieved by adjusting kinematic and kinetic parameters associated with each body part involved in the intended movement. The modifications of these parameters typically relies on sensory feedback from one or more sensory modalities ( see: multisensory integration), such as proprioception and vision. Properties Large Degrees of Freedom Goal-directed and coordinated movement of body parts is inherently variable because there are many ways of coordinating body parts to achieve the intended movement goal. This is because the degrees of freedom (DOF) is large for most movements due to the many associated neuro-musculoskeletal elements.Bernstein N. (1967). The Coordination and Regulation of Movements. Pergamon Press. New York. Some examples of non-repeatable movements are when pointing or standing up from sitting. Complexity The complexit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they are able to interact with neurotransmitter receptors on the target cell. The neurotransmitter's effect on the target cell is determined by the receptor it binds. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available and often require a small number of biosynthetic steps for conversion. Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified. Common neurotransmitters include glutamate, GABA, acetylcholine, glycine and norepinephrine. Mechanism and cycle Synthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticular Formation
The reticular formation is a set of interconnected nuclei that are located throughout the brainstem. It is not anatomically well defined, because it includes neurons located in different parts of the brain. The neurons of the reticular formation make up a complex set of networks in the core of the brainstem that extend from the upper part of the midbrain to the lower part of the medulla oblongata. The reticular formation includes ascending pathways to the cerebral cortex, cortex in the ascending reticular activating system (ARAS) and descending pathways to the spinal cord via the reticulospinal tracts. Neurons of the reticular formation, particularly those of the ascending reticular activating system, play a crucial role in maintaining behavioral arousal and consciousness. The overall functions of the reticular formation are modulatory and premotor, involving somatic motor control, cardiovascular control, pain modulation, sleep and consciousness, and habituation. The modulatory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Olivary Nucleus
The inferior olivary nucleus (ION), is a structure found in the medulla oblongata underneath the superior olivary nucleus.Gado, Thomas A. Woolsey; Joseph Hanaway; Mokhtar H. (2003). The brain atlas a visual guide to the human central nervous system (2nd ed.). Hoboken, NJ: Wiley. p. 206. . In vertebrates, the ION is known to coordinate signals from the spinal cord to the cerebellum to regulate motor coordination and learning.Schweighofer N, Lang EJ, Kawato M. Role of the olivo-cerebellar complex in motor learning and control. ''Frontiers in Neural Circuits''. 2013;7:94. . These connections have been shown to be tightly associated, as degeneration of either the cerebellum or the ION results in degeneration of the other. Neurons of the ION are glutamatergic and receive inhibitory input via GABA receptors. There are two distinct GABAα receptor populations that are spatially organized within each neuron present in the ION. The GABAα receptor make-up varies based on where the rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
