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Basket Cells
Basket cells are inhibitory GABAergic interneurons of the brain, found throughout different regions of the cortex and cerebellum. Anatomy and physiology Basket cells are multipolar GABAergic interneurons that function to make inhibitory synapses and control the overall potentials of target cells. In general, dendrites of basket cells are free branching, contain smooth spines, and extend from 3 to 9 mm. Axons are highly branched, ranging in total from 20 to 50mm in total length. The branched axonal arborizations give rise to the name as they appear as baskets surrounding the soma of the target cell. Basket cells form axo-somatic synapses, meaning their synapses target somas of other cells. By controlling the somas of other neurons, basket cells can directly control the action potential discharge rate of target cells. Basket cells can be found throughout the brain, in among other the cortex, hippocampus, amygdala, basal ganglia, and the cerebellum. Cortex In the cortex, basket cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folium (brain)
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 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 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 movement, equilibrium, posture, and motor learning in humans. Anatomically, the human cerebellum has the appearance of a separate structure attached to the bottom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrite
Dendrites (from Greek δένδρον ''déndron'', "tree"), also dendrons, are branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project. Electrical stimulation is transmitted onto dendrites by upstream neurons (usually via their axons) via synapses which are located at various points throughout the dendritic tree. Dendrites play a critical role in integrating these synaptic inputs and in determining the extent to which action potentials are produced by the neuron. Dendritic arborization, also known as dendritic branching, is a multi-step biological process by which neurons form new dendritic trees and branches to create new synapses. The morphology of dendrites such as branch density and grouping patterns are highly correlated to the function of the neuron. Malformation of dendrites is also tightly correlated to impaired nervous syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroscience Information Framework
The Neuroscience Information Framework is a repository of global neuroscience web resources, including experimental, clinical, and translational neuroscience databases, knowledge bases, atlases, and genetic/ genomic resources and provides many authoritative links throughout the neuroscience portal of Wikipedia. Description The Neuroscience Information Framework (NIF) is an initiative of the NIH Blueprint for Neuroscience Research, which was established in 2004 by the National Institutes of Health. Development of the NIF started in 2008, when the University of California, San Diego School of Medicine obtained an NIH contract to create and maintain "a dynamic inventory of web-based neurosciences data, resources, and tools that scientists and students can access via any computer connected to the Internet". The project is headed by Maryann Martone, co-director of the National Center for Microscopy and Imaging Research (NCMIR), part of the multi-disciplinary Center for Research in Bio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inhibitory Synapses
An inhibitory postsynaptic potential (IPSP) is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.Purves et al. Neuroscience. 4th ed. Sunderland (MA): Sinauer Associates, Incorporated; 2008. IPSP were first investigated in motorneurons by David P. C. Lloyd, John Eccles and Rodolfo Llinás in the 1950s and 1960s. The opposite of an inhibitory postsynaptic potential is an excitatory postsynaptic potential (EPSP), which is a synaptic potential that makes a postsynaptic neuron ''more'' likely to generate an action potential. IPSPs can take place at all chemical synapses, which use the secretion of neurotransmitters to create cell to cell signalling. Inhibitory presynaptic neurons release neurotransmitters that then bind to the postsynaptic receptors; this induces a change in the permeability of the postsynaptic neuronal membrane to particular ions. An electric current that changes the postsynaptic membrane potential to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excitatory Synapses
An excitatory synapse is a synapse in which an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell. Neurons form networks through which nerve impulses travel, each neuron often making numerous connections with other cells. These electrical signals may be excitatory or inhibitory, and, if the total of excitatory influences exceeds that of the inhibitory influences, the neuron will generate a new action potential at its axon hillock, thus transmitting the information to yet another cell. This phenomenon is known as an excitatory postsynaptic potential (EPSP). It may occur via direct contact between cells (i.e., via gap junctions), as in an electrical synapse, but most commonly occurs via the vesicular release of neurotransmitters from the presynaptic axon terminal into the synaptic cleft, as in a chemical synapse. The excitatory neurotransmitters, the most common of which is glutamate, then migrate via di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purkinje Cell
Purkinje cells, or Purkinje neurons, are a class of GABAergic inhibitory neurons located in the cerebellum. They are named after their discoverer, Czech people, Czech anatomist Jan Evangelista Purkyně, who characterized the cells in 1839. Structure These Cell (biology), cells are some of the largest neurons in the human brain (Betz cells being the largest), with an intricately elaborate dendrite, dendritic arbor, characterized by a large number of dendritic spines. Purkinje cells are found within the Cerebellum#Microanatomy, Purkinje layer in the cerebellum. Purkinje cells are aligned like dominos stacked one in front of the other. Their large dendritic arbors form nearly two-dimensional layers through which parallel fibers from the deeper-layers pass. These parallel fibers make relatively weaker excitatory synapse, excitatory (glutamatergic) synapses to spines in the Purkinje cell dendrite, whereas climbing fibers originating from the inferior olivary nucleus in the medull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Body
The soma (pl. ''somata'' or ''somas''), perikaryon (pl. ''perikarya''), neurocyton, or cell body is the bulbous, non-process portion of a neuron or other brain cell type, containing the cell nucleus. The word 'soma' comes from the Greek '' σῶμα'', meaning 'body'. Although it is often used to refer to neurons, it can also refer to other cell types as well, including astrocytes, oligodendrocytes, and microglia. There are many different specialized types of neurons, and their sizes vary from as small as about 5 micrometres to over 10 millimetres for some of the smallest and largest neurons of invertebrates, respectively. The soma of a neuron (i.e., the main part of the neuron in which the dendrites branch off of) contains many organelles, including granules called Nissl granules, which are composed largely of rough endoplasmic reticulum and free polyribosomes. The cell nucleus is a key feature of the soma. The nucleus is the source of most of the RNA that is produced in neuron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum - Biel - Very High Mag
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 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 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 movement, equilibrium, posture, and motor learning in humans. Anatomically, the human cerebellum has the appearance of a separate structure attached to the bott ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus Proper
The hippocampus proper refers to the actual structure of the hippocampus which is made up of three regions or subfields. The subfields CA1, CA2, and CA3 use the initials of cornu Ammonis, an earlier name of the hippocampus. Structure There are four hippocampal subfields, regions in the hippocampus proper which form a neural circuit called the trisynaptic circuit. CA1 CA1 is the first region in the hippocampal circuit, from which a major output pathway goes to layer V of the entorhinal cortex. Another significant output is to the subiculum. CA2 CA2 is a small region located between CA1 and CA3. It receives some input from layer II of the entorhinal cortex via the perforant path. Its pyramidal cells are more like those in CA3 than those in CA1. It is often ignored due to its small size. CA3 CA3 receives input from the mossy fibers of the granule cells in the dentate gyrus, and also from cells in the entorhinal cortex via the perforant path. The mossy fiber pathway ends in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Action Potential
An action potential occurs when the membrane potential of a specific cell location rapidly rises and falls. This depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and in some plant cells. Certain endocrine cells such as pancreatic beta cells, and certain cells of the anterior pituitary gland are also excitable cells. In neurons, action potentials play a central role in cell-cell communication by providing for—or with regard to saltatory conduction, assisting—the propagation of signals along the neuron's axon toward synaptic boutons situated at the ends of an axon; these signals can then connect with other neurons at synapses, or to motor cells or glands. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of events l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parvalbumin
Parvalbumin (PV) is a calcium-binding protein with low molecular weight (typically 9-11 kDa). In humans, it is encoded by the ''PVALB'' gene. It is not a member of the albumin family; it is named for its size (''parv-'', from Latin ''parvus'' small) and its ability to coagulate. It has three EF hand motifs and is structurally related to calmodulin and troponin C. Parvalbumin is found in fast-contracting muscles, where its levels are highest, as well as in the brain and some endocrine tissues. Parvalbumin is a small, stable protein containing EF-hand type calcium binding sites. It is involved in calcium signaling. Typically, this protein is broken into three domains, domains AB, CD and EF, each individually containing a helix-loop-helix motif. The AB domain houses a two amino-acid deletion in the loop region, whereas domains CD and EF contain the N-terminal and C-terminal, respectively. Calcium binding proteins like parvalbumin play a role in many physiological processes, namely c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyramidal Neuron
Pyramidal cells, or pyramidal neurons, are a type of multipolar neuron found in areas of the brain including the cerebral cortex, the hippocampus, and the amygdala. Pyramidal neurons are the primary excitation units of the mammalian prefrontal cortex and the corticospinal tract. Pyramidal neurons are also one of two cell types where the characteristic sign, Negri bodies, are found in post-mortem rabies infection. Pyramidal neurons were first discovered and studied by Santiago Ramón y Cajal. Since then, studies on pyramidal neurons have focused on topics ranging from neuroplasticity to cognition. Structure File:GFPneuron.png, Pyramidal neuron visualized by green fluorescent protein (gfp) File:Hippocampal-pyramidal-cell.png, A hippocampal pyramidal cell One of the main structural features of the pyramidal neuron is the conic shaped soma, or cell body, after which the neuron is named. Other key structural features of the pyramidal cell are a single axon, a large apical dendrite, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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