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Inhibitor
Inhibitor or inhibition may refer to: Biology * Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity * Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotransmitter * Lateral inhibition, a neural mechanism that increases contrast between active and (neighbouring) inactive neurons * Inhibitory postsynaptic potential, a synaptic potential that decreases the firing of a neuron Chemistry * Corrosion inhibitor, a substance that decreases the rate of metal oxidation * Reaction inhibitor, a substance that prevents or decreases the rate of a chemical reaction * Polymerisation inhibitor, a substance that inhibits unwanted polymerisation of monomers Psychology * Cognitive inhibition, the mind's ability to tune out irrelevant stimuli ** Inhibitory control, a cognitive process that permits an individual to inhibit their impulses * Inhibition of return, a feature of attention * Latent inhibition, a term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Inhibitor
An enzyme inhibitor is a molecule that binds to an enzyme and blocks its Enzyme activity, activity. Enzymes are proteins that speed up chemical reactions necessary for life, in which Substrate (biochemistry), substrate molecules are converted into Product (chemistry), products. An enzyme Enzyme catalysis, facilitates a specific chemical reaction by binding the substrate to its active site, a specialized area on the enzyme that accelerates the Rate-determining step, most difficult step of the reaction. An enzyme inhibitor stops ("inhibits") this process, either by binding to the enzyme's active site (thus preventing the substrate itself from binding) or by binding to another site on the enzyme such that the enzyme's catalysis of the reaction is blocked. Enzyme inhibitors may bind Reversible reaction, reversibly or irreversibly. Irreversible inhibitors form a Covalent bond, chemical bond with the enzyme such that the enzyme is inhibited until the chemical bond is broken. By cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reuptake Inhibitor
Reuptake inhibitors (RIs) are a type of reuptake modulators. It is a drug that inhibits the plasmalemmal transporter-mediated reuptake of a neurotransmitter from the synapse into the pre-synaptic neuron. This leads to an increase in extracellular concentrations of the neurotransmitter and an increase in neurotransmission. Various drugs exert their psychological and physiological effects through reuptake inhibition, including many antidepressants and psychostimulants. Most known reuptake inhibitors affect the monoamine neurotransmitters serotonin, norepinephrine (and epinephrine), and dopamine. However, there are also a number of pharmaceuticals and research chemicals that act as reuptake inhibitors for other neurotransmitters such as glutamate, γ-aminobutyric acid (GABA), glycine, adenosine, choline (the precursor of acetylcholine), and the endocannabinoids, among others. Mechanism of action Active site transporter substrates Standard reuptake inhibitors are belie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inhibitory Postsynaptic Potential
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. 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. EPSPs and IPSPs compete with each other at numerous synapses of a neuron. This determines whether an action potential occurring at the presynaptic terminal produces an action potential at the postsynaptic membrane. Some common neurotransmitters involved in IPSPs are GABA and glycine. Inhibitory presynaptic neurons release neurotransmitters that then bind to the postsynaptic receptors; this induces a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corrosion Inhibitor
A corrosion inhibitor or anti-corrosive is a chemical compound added to a liquid or gas to decrease the corrosion rate of a metal that comes into contact with the fluid. The effectiveness of a corrosion inhibitor depends on fluid composition and dynamics. Corrosion inhibitors are common in industry, and also found in over-the-counter products, typically in spray form in combination with a lubricant and sometimes a penetrating oil. They may be added to water to prevent leaching of lead or copper from pipes. A common mechanism for inhibiting corrosion involves formation of a coating, often a passivation layer, which prevents access of the corrosive substance to the metal. Permanent treatments such as chrome plating are not generally considered inhibitors, however: corrosion inhibitors are additives to the fluids that surround the metal or related object. Types The nature of the corrosive inhibitor depends on (i) the material being protected, which are most commonly metal object ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inhibitory Control
Inhibitory control, also known as response inhibition, is a cognitive process – and, more specifically, an executive function – that permits an individual to inhibit their impulses and natural, habitual, or dominant behavioral responses to stimuli ( prepotent responses) in order to select a more appropriate behavior that is consistent with completing their goals. Self-control is an important aspect of inhibitory control. For example, successfully suppressing the natural behavioral response to eat cake when one is craving it while dieting requires the use of inhibitory control. The prefrontal cortex, caudate nucleus, and subthalamic nucleus are known to regulate inhibitory control cognition. Inhibitory control is impaired in both addiction and attention deficit hyperactivity disorder. In healthy adults and ADHD individuals, inhibitory control improves over the short term with low (therapeutic) doses of methylphenidate or amphetamine. Inhibitory control may also be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymerisation Inhibitor
In polymer chemistry, polymerisation inhibitors (US: polymerization inhibitors) are chemical compounds added to monomers to prevent their self-polymerisation. Unsaturated monomers such as acrylates, vinyl chloride, butadiene and styrene require inhibitors for both processing and safe transport and storage. Many monomers are purified industrially by distillation, which can lead to thermally-initiated polymerisation. Styrene, for example, is distilled at temperatures above 100 °C whereupon it undergoes thermal polymerisation at a rate of ~2% per hour. This polymerisation is undesirable, as it can foul the fractionating tower; it is also typically exothermic, which can lead to a runaway reaction and potential explosion if left unchecked. Once initiated, polymerisation is typically radical in mechanism and as such many polymerisation inhibitors act as radical scavengers. Inhibitors vs retarders The term 'inhibitor' is often used in a general sense to describe any compound us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Inhibitor
A reaction inhibitor is a substance that decreases the rate of, or prevents, a chemical reaction. A catalyst or an Enzyme activator, in contrast, is a substance that increases the rate of a chemical reaction. Examples * Added acetanilide slows the decomposition of drug-store hydrogen peroxide solution, inhibiting the reaction 2 → 2 + , which is catalyzed by heat, light, and impurities.The decomposition of hydrogen peroxide Inhibition of a catalyst An inhibitor can reduce the effectiveness of a catalyst in a catalysed reaction (either a non-biological catalyst or an enzyme). E.g., if a compound is so similar to (one of) the reactants that it can bind to the active site of a catalyst but does not undergo a catalytic reaction then that catalyst molecule cannot perform its job because the active site is occupied. When the inhibitor is released, the catalyst is again available for reaction. Inhibition and catalyst poisoning Inhibition should be distinguished from catalyst poisoning. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cognitive Inhibition
Cognitive inhibition refers to the mind's ability to tune out stimuli that are irrelevant to the task/process at hand or to the mind's current state. Additionally, it can be done either in whole or in part, intentionally or otherwise. Cognitive inhibition in particular can be observed in many instances throughout specific areas of cognitive science. History The early models of what would become the study and concept of cognitive inhibition were developed by Sigmund Freud. Inhibition was believed to play two primary roles: the prevention of unwanted thoughts or behaviors, and the repression of experiences from infancy and childhood. Freud believed cognitive inhibition was not just a lack of awareness to stimuli, but an active process, requiring a constant energy expenditure. Other early theories of cognitive inhibition focused on its central developmental mechanisms and were founded by Luria and Vygotsky, two Russian psychologists. They proposed that children acquire control of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Inhibition
In neurobiology, lateral inhibition is the capacity of an excited neuron to reduce the activity of its neighbors. Lateral inhibition disables the spreading of action potentials An action potential (also known as a nerve impulse or "spike" when in a neuron) is a series of quick changes in voltage across a cell membrane. An action potential occurs when the membrane potential of a specific cell rapidly rises and falls. ... from excited neurons to neighboring neurons in the lateral direction. This creates a contrast in stimulation that allows increased sensory perception. It is also referred to as lateral antagonism and occurs primarily in visual processes, but also in Touch, tactile, Auditory system, auditory, and even olfactory processing. Cells that utilize lateral inhibition appear primarily in the cerebral cortex and thalamus and make up lateral inhibitory networks (LINs). Artificial lateral inhibition has been incorporated into artificial sensory systems, such as vision c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Inhibition
In psychology, memory inhibition is the ability ''not'' to remember irrelevant information. The scientific concept of memory inhibition should not be confused with everyday uses of the word "inhibition". Scientifically speaking, memory inhibition is a type of cognitive inhibition, which is the stopping or overriding of a mental process, in whole or in part, with or without intention. Memory inhibition is a critical component of an effective memory system. While some memories are retained for a lifetime, most memories are forgotten. According to evolutionary psychologists, forgetting is adaptive because it facilitates selectivity of rapid, efficient recollection. For example, a person trying to remember where they parked their car would not want to remember every place they have ever parked. In order to remember something, therefore, it is essential not only to activate the relevant information, but also to inhibit irrelevant information. There are many memory phenomena that seem t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inhibition Of Return
Inhibition of return (IOR) refers to an orientation mechanism that briefly enhances (for approximately 100–300 milliseconds (ms)) the speed and accuracy with which an object is detected after the object is attended, but then impairs detection speed and accuracy (for approximately 500–3000 milliseconds). IOR is usually measured with a cue-response paradigm, in which a person presses a button when they detect a target stimulus following the presentation of a cue that indicates the location in which the target will appear. The cue can be exogenous (or peripheral), or endogenous. Inhibition of return results from oculomotor activation, regardless of whether it was produced by exogenous signals or endogenously. Although IOR occurs for both visual and auditory stimuli, IOR is greater for visual stimuli, and is studied more often than auditory stimuli. Description IOR was first described in depth by Michael Posner and Yoav Cohen, who discovered that, contrary to their expectations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latent Inhibition
Latent inhibition (LI) is a technical term in classical conditioning, where a familiar stimulus takes longer to acquire meaning (as a signal or conditioned stimulus) than a new stimulus. The term originated with Lubow and Moore in 1973. The LI effect is latent in that it is not exhibited in the stimulus pre-exposure phase, but rather in the subsequent test phase. "Inhibition", here, simply connotes that the effect is expressed in terms of relatively poor learning. The LI effect is extremely robust, appearing in both invertebrate (for example, honey bees) and mammalian species that have been tested and across many different learning paradigms, thereby suggesting some adaptive advantages, such as protecting the organism from associating irrelevant stimuli with other, more important, events. Theories The LI effect has received a number of theoretical interpretations. One class of theory holds that inconsequential stimulus pre-exposure results in reduced associability for that stimul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
