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A neural pathway is a neural tract connecting one part of the nervous system with another, usually consisting of bundles of elongated, myelin-insulated neurons, known collectively as white matter. The nervous system is a Network of specialized cells that communicate information about an animal's surroundings and itself The nervous system is a Network of specialized cells that communicate information about an animal's surroundings and itself Myelin is an electrically-insulating Dielectric Phospholipid layer that surrounds only the Axons of many Neurons It is an outgrowth Neurons (ˈnjuːɹɒn also known as neurones and nerve cells) are responsive cells in the Nervous system that process and transmit information White matter is one of the three main solid components of the Central nervous system. Neural pathways serve to connect relatively distant areas of the brain or nervous system, compared to the local communication of grey matter. The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain

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Naming of neural pathways

The first named pathways were evident even in a poorly-preserved gross brain, and were named by the great anatomists of the Renaissance using cadaver material. The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain The Renaissance (from French Renaissance, meaning "rebirth" Italian: Rinascimento, from re- "again" and nascere Examples of these include the great commissures of the brain such as the corpus callosum (Latin, "huge body"), anterior commissure, and posterior commissure. The corpus callosum is a structure of the Mammalian Brain in the longitudinal fissure that connects the left and right Cerebral hemispheres It also facilitates Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Further examples of this (by no means a complete list) include the pyramidal tract, crus cerebri (Latin, "leg of the brain"), and cerebellar peduncles (Latin, "little foot of the cerebellum"). The corticospinal or pyramidal tract is a massive collection of Axons that travel between the Cerebral cortex of the Brain and the Spinal The cerebral peduncle, by most classifications is everything in the Mesencephalon except the Tectum. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. The cerebellum ( Latin: "little brain" is a region of the Brain that plays an important role in the integration of sensory perception Note that these names describe the appearance of a structure but give one no information on its function or location.

Later, as neuroanatomical knowledge became more sophisticated, the trend was toward naming pathways by their origin and termination. Neuroanatomy is the science for localizing function in the Human brain. For example, the nigrostriatal pathway, which is degenerated in Parkinson's disease, runs from the substantia nigra (Latin, "black substance") to the corpus striatum (Latin, "striped body"). The nigrostriatal pathway is a Neural pathway that connects the Substantia nigra with the Striatum. Parkinson's disease (also known as Parkinson disease or PD) is a degenerative disorder of the Central nervous system that often impairs the sufferer's The substantia nigra ( Latin for "black substance" Sömmering) or locus niger is a heterogeneous portion of the midbrain, separating Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. The striatum is a subcortical (ie inside rather than on the outside part of the Telencephalon. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. This naming can extend to include any number of structures in a pathway, such that the cerebellorubrothalamocortical pathway originates in the cerebellum, synapses in the red nucleus ("ruber" in Latin), on to the thalamus, and finally terminating in the cerebral cortex. The cerebellum ( Latin: "little brain" is a region of the Brain that plays an important role in the integration of sensory perception Chemical synapses are specialized junctions through which Neurons signal to each other and to non-neuronal cells such as those in Muscles or Glands The red nucleus is a structure in the Rostral Midbrain involved in Motor coordination. The thalamus (from Greek θάλαμος = room chamber, IPA= /ˈθæləməs/ is a pair and symmetric part of the brain The cerebral cortex is a structure within the Brain that plays a key role in Memory, Attention, perceptual Awareness, Thought,

Sometimes, these two naming conventions coexist. For example, the name "pyramidal tract" has been mainly supplanted by lateral corticospinal tract in most texts. The corticospinal or pyramidal tract is a massive collection of Axons that travel between the Cerebral cortex of the Brain and the Spinal The corticospinal or pyramidal tract is a massive collection of Axons that travel between the Cerebral cortex of the Brain and the Spinal Note that the "old" name was primarily descriptive, evoking the pyramids of antiquity, from the appearance of this neural pathway in the medulla oblongata. The Great Pyramid of Giza, also called Khufu's Pyramid or the Pyramid of Khufu, and Pyramid of Cheops, is the oldest and largest of the three The medulla oblongata is the lower portion of the Brainstem. It deals with autonomic functions such as breathing and blood pressure The "new" name is based primarily on its origin (in the primary motor cortex, Brodmann area 4) and termination (onto the alpha motor neurons of the spinal cord). The cerebral cortex is a structure within the Brain that plays a key role in Memory, Attention, perceptual Awareness, Thought, A Brodmann area is a region of the cortex defined based on its Cytoarchitecture, or organization of cells In Vertebrates the term motor neuron (or motoneuron) classically applies to Neurons located in the Central nervous system (or CNS that project The spinal cord is a long thin tubular bundle of Nerves that is an extension of the Central nervous system from the brain and is enclosed in and protected

Functional aspects

In general, neurons receive information either at their dendrites or cell bodies. Neurons (ˈnjuːɹɒn also known as neurones and nerve cells) are responsive cells in the Nervous system that process and transmit information Dendrites (from Greek δένδρον déndron, “tree” are the branched projections of a Neuron that act to conduct the electrochemical The soma, or cyton or perikaryon, is the bulbous end of a Neuron, containing the Cell nucleus. The axon of a nerve cell is, in general, responsible for transmitting information over a relatively long distance. An axon or nerve fiber is a long slender projectionof a nerve cell or Neuron, that conducts electrical impulses away from the neuron's Cell Therefore, most neural pathways are made up of axons. An axon or nerve fiber is a long slender projectionof a nerve cell or Neuron, that conducts electrical impulses away from the neuron's Cell If the axons have myelin sheaths, then the pathway appears bright white because myelin is primarily lipid. An axon or nerve fiber is a long slender projectionof a nerve cell or Neuron, that conducts electrical impulses away from the neuron's Cell Myelin is an electrically-insulating Dielectric Phospholipid layer that surrounds only the Axons of many Neurons It is an outgrowth Myelin is an electrically-insulating Dielectric Phospholipid layer that surrounds only the Axons of many Neurons It is an outgrowth Lipids are broadly defined as any fat- Soluble ( lipophilic) naturally-occurring Molecule, such as fats oils waxes cholesterol sterols fat-soluble If most or all of the axons lack myelin sheaths (i. Myelin is an electrically-insulating Dielectric Phospholipid layer that surrounds only the Axons of many Neurons It is an outgrowth e. , are unmyelinated), then the pathway will appear a darker beige color, which is generally called gray (American English, or grey in British English). Phonology North American English regional phonology In many ways compared to English English, North American English is conservative in its Phonology. British English or UK English ( BrE, BE, en-GB) is the broad term used to distinguish the forms of the English language used in the

Some neurons are responsible for conveying information over long distances. For example, motor neurons, which travel from the spinal cord to the muscle, can have axons up to a meter in length in humans; the longest axon in the human body is almost two meters long in tall individuals and runs from the great toe to the medulla oblongata of the brainstem. In Vertebrates the term motor neuron (or motoneuron) classically applies to Neurons located in the Central nervous system (or CNS that project Toes are the digits of the Foot of an animal Many animal species such as Cats walk on their toes and are described as being Digitigrade The medulla oblongata is the lower portion of the Brainstem. It deals with autonomic functions such as breathing and blood pressure The brain stem (or brainstem) is the lower part of the Brain, adjoining and structurally continuous with the Spinal cord. These are archetypical examples of neural pathways.

Major neural pathways

Dopamine pathways:

References

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