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Gustatory Cortex
The primary gustatory cortex (GC) is a brain structure responsible for the perception of taste. It consists of two substructures: the anterior insula on the insular lobe and the frontal operculum on the inferior frontal gyrus of the frontal lobe. Because of its composition the primary gustatory cortex is sometimes referred to in literature as the AI/FO(Anterior Insula/Frontal Operculum). By using extracellular unit recording techniques, scientists have elucidated that neurons in the AI/FO respond to sweetness, saltiness, bitterness, and sourness, and they code the intensity of the taste stimulus. Role in the taste pathway Like the olfactory system, the taste system is defined by its specialized peripheral receptors and central pathways that relay and process taste information. Peripheral taste receptors are found on the upper surface of the tongue, soft palate, pharynx, and the upper part of the esophagus. Taste cells synapse with primary sensory axons that run in the cho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Taste
The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste. Taste is the perception stimulated when a substance in the mouth biochemistry, reacts chemically with taste receptor cells located on taste buds in the oral cavity, mostly on the tongue. Taste, along with olfaction, the sense of smell and trigeminal nerve stimulation (registering texture, pain, and temperature), determines Flavoring, flavors of food and other substances. Humans have taste receptors on taste buds and other areas, including the upper surface of the tongue and the epiglottis. The gustatory cortex is responsible for the perception of taste. The tongue is covered with thousands of small bumps called lingual papillae, papillae, which are visible to the naked eye. Within each papilla are hundreds of taste buds. The exceptions to this is the filiform papillae that do not contain taste buds. There are between 2000 and 5000Boron, W.F., E.L. Boulpaep. 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Ventral Posterior Medial Nucleus
The ventral posteromedial nucleus (VPM) is a nucleus within the ventral posterior nucleus of the thalamus and serves an analogous somatosensory relay role for the ascending trigeminothalamic tracts as its lateral neighbour the ventral posterolateral nucleus serves for dorsal column–medial lemniscus pathway 2nd-order neurons. The term "ventral posteromedial nucleus" was introduced by Le Gros Clark in 1930. Afferents and efferents Orofacial somatosensory The VPM receives second-order general somatic afferent fibers from the ventral trigeminal tract and the dorsal trigeminal tract which convey general somatic sensory information from the face and oral cavity (including touch, pressure, temperature, pain, and propriception). Proprioceptive synapses are situated anteriorly, ones mediating touch in the middle, and nociceptive ones posteriorly. Third-order neurons in turn project to the somatosensory cortex in the postcentral gyrus. Taste The VPM receives second-order taste s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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NaCl
Sodium chloride , commonly known as edible salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. It is transparent or translucent, brittle, hygroscopic, and occurs as the mineral halite. In its edible form, it is commonly used as a condiment and food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further chemical syntheses. Another major application of sodium chloride is deicing of roadways in sub-freezing weather. Uses In addition to the many familiar domestic uses of salt, more dominant applications of the approximately 250 million tonnes per year production (2008 data) include chemicals and de-icing.Westphal, Gisbert ''et al.'' (2002) "Sodium Chloride" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim . Chemical functions Salt is used, directly or indirectly, in the prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Sucrose
Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined from either sugarcane or sugar beet. Sugar mills – typically located in tropical regions near where sugarcane is grown – crush the cane and produce raw sugar which is shipped to other factories for refining into pure sucrose. Sugar beet factories are located in temperate climates where the beet is grown, and process the beets directly into refined sugar. The Sugar refinery, sugar-refining process involves washing the raw sugar crystals before dissolving them into a sugar syrup which is filtered and then passed over carbon to remove any residual colour. The sugar syrup is then concentrated by boiling under a vacuum and crystallized as the final purification process to produce crystals of pure sucrose that are clear, odorless, and sweet. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Monosodium Glutamate
Monosodium glutamate (MSG), also known as sodium glutamate, is a sodium salt of glutamic acid. MSG is found naturally in some foods including tomatoes and cheese in this glutamic acid form. MSG is used in cooking as a flavor enhancer with a savory taste that intensifies the umami flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups. MSG was first prepared in 1908 by Japanese biochemist Kikunae Ikeda, who tried to isolate and duplicate the savory taste of ''kombu'', an edible seaweed used as a broth ('' dashi'') for Japanese cuisine. MSG balances, blends, and rounds the perception of other tastes. MSG, along with disodium ribonucleotides, is commonly used and found in stock (bouillon) cubes, soups, ramen, gravy, stews, condiments, savory snacks, etc. The U.S. Food and Drug Administration has given MSG its generally recognized as safe (GRAS) designation. It is a popular misconception that MSG can cause headaches and other feelings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Temporal Coding
Neural coding (or neural representation) is a neuroscience field concerned with characterising the hypothetical relationship between the stimulus and the neuronal responses, and the relationship among the electrical activities of the neurons in the ensemble. Based on the theory that sensory and other information is represented in the brain by networks of neurons, it is believed that neurons can encode both digital and analog information. Overview Neurons have an ability uncommon among the cells of the body to propagate signals rapidly over large distances by generating characteristic electrical pulses called action potentials: voltage spikes that can travel down axons. Sensory neurons change their activities by firing sequences of action potentials in various temporal patterns, with the presence of external sensory stimuli, such as light, sound, taste, smell and touch. Information about the stimulus is encoded in this pattern of action potentials and transmitted into and aro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Functional Magnetic Resonance Imaging
Functional magnetic resonance imaging or functional MRI (fMRI) measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases. The primary form of fMRI uses the blood-oxygen-level dependent (BOLD) contrast, discovered by Seiji Ogawa in 1990. This is a type of specialized brain and body scan used to map neuron, neural activity in the brain or spinal cord of humans or other animals by imaging the change in blood flow (hemodynamic response) related to energy use by brain cells. Since the early 1990s, fMRI has come to dominate brain mapping research because it does not involve the use of injections, surgery, the ingestion of substances, or exposure to ionizing radiation. This measure is frequently corrupted by noise from various sources; hence, statistical procedures are used to extract the underlying si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Calcium Imaging
Calcium imaging is a microscopy technique to optically measure the calcium (Ca2+) status of an isolated cell, tissue or medium. Calcium imaging takes advantage of calcium indicators, fluorescent molecules that respond to the binding of Ca2+ ions by fluorescence properties. Two main classes of calcium indicators exist: chemical indicators and genetically encoded calcium indicators (GECI). This technique has allowed studies of calcium signalling in a wide variety of cell types, and can be used to measure electrical activity in hundreds of neurons in cell culture, or in living animals during ongoing behavior. Chemical indicators Chemical indicators are small molecules that can chelate calcium ions. All these molecules are based on an EGTA homologue called BAPTA, with high selectivity for calcium (Ca2+) ions versus magnesium (Mg2+) ions. This group of indicators includes fura-2, indo-1, fluo-3, fluo-4, Calcium Green-1. These dyes are often used with the chelator carboxyl grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Population Coding
Neural coding (or neural representation) is a neuroscience field concerned with characterising the hypothetical relationship between the Stimulus (physiology), stimulus and the neuronal responses, and the relationship among the Electrophysiology, electrical activities of the neurons in the Neuronal ensemble, ensemble. Based on the theory that sensory and other information is represented in the brain by Biological neural network, networks of neurons, it is believed that neurons can encode both Digital data, digital and analog signal, analog information. Overview Neurons have an ability uncommon among the cells of the body to propagate signals rapidly over large distances by generating characteristic electrical pulses called action potentials: voltage spikes that can travel down axons. Sensory neurons change their activities by firing sequences of action potentials in various temporal patterns, with the presence of external sensory stimuli, such as light, sound, taste, Olfaction, sm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Topographic Map (neuroanatomy)
In neuroanatomy, topographic map is the ordered projection of a sensory surface (like the retina or the skin) or an effector system (like the musculature) to one or more structures of the central nervous system. Topographic maps can be found in all sensory systems and in many motor systems. Visual system The visual system refers to the part of the central nervous system that allows an organism to see. It interprets information from visible light to build a representation of the world. The ganglion cells of the retina project in an orderly fashion to the lateral geniculate nucleus (LGN) of the thalamus and from there to the primary visual cortex (V1); adjacent spots on the retina are represented by adjacent neurons in the lateral geniculate nucleus and the primary visual cortex. The term for this pattern of projection is ''topography''. There are many types of topographic maps in the visual cortices, including retinotopic maps, ocular dominance maps and orientation maps. Retinotop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Olfactory
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it occurs when an odor binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. There are many different things which can interfere with a normal sense of smell, including damage to the nose or smell receptors, anosmia, upper respiratory infections, traumatic brain injury, and neurodegenerative disease. History of study Early scientific study of the sense of smell includes the extensive doctoral dissertation of Eleanor Gamble, published in 1898, which compared olfactory to othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Field Potential
Local field potentials (LFP) are transient electrical signals generated in nerves and other tissues by the summed and synchronous electrical activity of the individual cells (e.g. neurons) in that tissue. LFP are "extracellular" signals, meaning that they are generated by transient imbalances in ion concentrations in the spaces outside the cells, that result from cellular electrical activity. LFP are 'local' because they are recorded by an electrode placed nearby the generating cells. As a result of the Inverse-square law, such electrodes can only 'see' potentials in a spatially limited radius. They are 'potentials' because they are generated by the voltage that results from charge separation in the extracellular space. They are 'field' because those extracellular charge separations essentially create a local electric field. LFP are typically recorded with a high-impedance microelectrode placed in the midst of the population of cells generating it. They can be recorded, for exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |