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Habituation
Habituation is a form of non-associative learning in which an organism’s non-reinforced response to an inconsequential stimulus decreases after repeated or prolonged presentations of that stimulus. For example, organisms may habituate to repeated sudden loud noises when they learn that these have no consequences. Habituation can occur in responses that habituate include those that involve an entire organism or specific biological component systems of an organism. The broad ubiquity of habituation across all forms of life has led to it being called "the simplest, most universal form of learning...as fundamental a characteristic of life as DNA." Functionally, habituation is thought to free up cognitive resources for other stimuli that are associated with biologically important events by diminishing the response to inconsequential stimuli. A progressive decline of a behavior in a habituation procedure may also reflect nonspecific effects such as fatigue, which must be ruled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dishabituation
Dishabituation (or dehabituation) is a form of recovered or restored behavioral response wherein the reaction towards a known stimulus is enhanced, as opposed to habituation. Initially, it was proposed as an explanation to increased response for a habituated behavior by introducing an external stimulus; however, upon further analysis, some have suggested that a proper analysis of dishabituation should be taken into consideration only when the response is increased by implying the original stimulus. Based on studies conducted over habituation's dual-process theory which attributed towards dishabituation, it is also determined that the latter was independent of any behavioral sensitization. History The phenomenon was studied by an early scientist Samuel Jackson Holmes in 1912, while he was studying the animal behavior in sea urchins. Later in 1933, George Humphrey—while studying the same effects in human babies and extensively over lower vertebrates—argued that dishabituati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-associative Learning
Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, non-human animals, and some machines; there is also evidence for some kind of learning in certain plants. Some learning is immediate, induced by a single event (e.g. being burned by a hot stove), but much skill and knowledge accumulate from repeated experiences. The changes induced by learning often last a lifetime, and it is hard to distinguish learned material that seems to be "lost" from that which cannot be retrieved. Human learning starts at birth (it might even start before) and continues until death as a consequence of ongoing interactions between people and their environment. The nature and processes involved in learning are studied in many established fields (including educational psychology, neuropsychology, experimental psychology, cognitive sciences, and pedagogy), as well as emerging fields of knowl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Adaptation
Neural adaptation or sensory adaptation is a gradual decrease over time in the responsiveness of the sensory system to a constant stimulus. It is usually experienced as a change in the stimulus. For example, if a hand is rested on a table, the table's surface is immediately felt against the skin. Subsequently, however, the sensation of the table surface against the skin gradually diminishes until it is virtually unnoticeable. The sensory neurons that initially respond are no longer stimulated to respond; this is an example of neural adaptation. All sensory and neural systems have a form of adaptation to constantly detect changes in the environment. Neural receptor cells that process and receive stimulation go through constant changes for mammals and other living organisms to sense vital changes in their environment. Some key players in several neural systems include Ca2+ions (see Calcium in biology) that send negative feedback in second messenger pathways that allow the neural r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Associative Learning
Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, non-human animals, and some machines; there is also evidence for some kind of learning in certain plants. Some learning is immediate, induced by a single event (e.g. being burned by a hot stove), but much skill and knowledge accumulate from repeated experiences. The changes induced by learning often last a lifetime, and it is hard to distinguish learned material that seems to be "lost" from that which cannot be retrieved. Human learning starts at birth (it might even start before) and continues until death as a consequence of ongoing interactions between people and their environment. The nature and processes involved in learning are studied in many established fields (including educational psychology, neuropsychology, experimental psychology, cognitive sciences, and pedagogy), as well as emerging fields of kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychological Dependence
Psychological dependence is a cognitive disorder and a form of dependence that is characterized by emotional–motivational withdrawal symptoms upon cessation of prolonged drug use or certain repetitive behaviors. Consistent and frequent exposure to particular substances or behaviors is responsible for inducing psychological dependence, requiring ongoing engagement to prevent the onset of an unpleasant withdrawal syndrome driven by negative reinforcement. Neuronal counter-adaptation is believed to contribute to the generation of withdrawal symptoms through changes in neurotransmitter activity or altered receptor expression. Environmental enrichment and physical activity have been shown to attenuate withdrawal symptoms. Symptoms Psychological withdrawal symptoms include: * Anhedonia *Anxiety * Changes in appetite * Craving for responsible stimulus *Dysphoria * Exhaustion *Insomnia / Hypersomnia * Irritability *Panic attack * Stress Development Psychological dependence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surgeon General Of The United States
The surgeon general of the United States is the operational head of the United States Public Health Service Commissioned Corps (PHSCC) and thus the leading spokesperson on matters of public health in the federal government of the United States. The surgeon general's office and staff are known as the Office of the Surgeon General (OSG), which is housed within the Office of the Assistant Secretary for Health. The U.S. surgeon general is nominated by the president of the United States and Senate Confirmation, confirmed by the United States Senate, Senate. The surgeon general must be appointed from individuals who are members of the United States Public Health Service Commissioned Corps, regular corps of the United States Public Health Service, U.S. Public Health Service and have specialized training or significant experience in public health programs. However, there is no time requirement for membership in the Public Health Service before holding the office of the Surgeon General, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positron Emission Tomography
Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body, such as: * Fluorodeoxyglucose ( 18F">sup>18FDG or FDG) is commonly used to detect cancer; * 18Fodium fluoride">sup>18Fodium fluoride (Na18F) is widely used for detecting bone formation; * Oxygen-15 (15O) is sometimes used to measure blood flow. PET is a common imaging technique, a medical scintillography technique used in nuclear medicine. A radiopharmaceutical—a radioisotope attached to a drug—is injected into the body as a tracer. When the radiopharmaceutical undergoes beta plus decay, a positron is emitted, and when the positron interacts with an ordinary electron, the tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroimaging
Neuroimaging is the use of quantitative (computational) techniques to study the neuroanatomy, structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive manner. Increasingly it is also being used for quantitative research studies of brain disease and psychiatric illness. Neuroimaging is highly multidisciplinary involving neuroscience, computer science, psychology and statistics, and is not a medical specialty. Neuroimaging is sometimes confused with neuroradiology. Neuroradiology is a medical specialty that uses non-statistical brain imaging in a clinical setting, practiced by radiologists who are medical practitioners. Neuroradiology primarily focuses on recognizing brain lesions, such as vascular diseases, strokes, tumors, and inflammatory diseases. In contrast to neuroimaging, neuroradiology is qualitative (based on subjective impressions and extensive clinical training) but sometime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychology
Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feelings, and motivation, motives. Psychology is an academic discipline of immense scope, crossing the boundaries between the Natural science, natural and social sciences. Biological psychologists seek an understanding of the Emergence, emergent properties of brains, linking the discipline to neuroscience. As social scientists, psychologists aim to understand the behavior of individuals and groups.Hockenbury & Hockenbury. Psychology. Worth Publishers, 2010. A professional practitioner or researcher involved in the discipline is called a psychologist. Some psychologists can also be classified as Behavioural sciences, behavioral or Cognitive science, cognitive scientists. Some psychologists attempt to understand the role of mental functions in i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stentor Coeruleus
''Stentor coeruleus'' () is a protist in the family Stentoridae which is characterized by being a very large ciliate that measures 0.5 to 2 millimetres when fully extended. ''S. coeruleus'' specifically appears as a very large trumpet. It contains a macronucleus that looks like a string of beads that are contained within a ciliate that is blue to blue-green in color. It has the ability to contract into a ball through the contraction of its many myonemes . ''Stentor coeruleus'' is known for its regenerative abilities. When this organism is cut in half, each half is able to regenerate a cell that has its normal anatomy provided that each cut part includes some of the macro-nucleus. It feeds by means of cilia that carry food into the gullet. DNA The genetic code is the standard code, and not the usual form for ciliates. The introns are unusually small, only 15 or 16 nucleotides long. Reproduction ''S. coeruleus'' is capable of sexual reproduction, or conjugation, but primaril ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mimosa Pudica
''Mimosa pudica'' (also called sensitive plant, sleepy grass, sleepy plant, action plant, humble plant, touch-me-not, touch-and-die, or shameplant) is a creeping annual or perennial flowering plant of the pea/legume family Fabaceae. It is often grown for its curiosity value: the sensitive compound leaves quickly fold inward and droop when touched or shaken and re-open a few minutes later. For this reason, this species is commonly cited as an example of rapid plant movement. Like a number of other plant species, it undergoes changes in leaf orientation termed "sleep" or nyctinastic movement. The foliage closes during darkness and reopens in light. This was first studied by French scientist Jean-Jacques d'Ortous. In the UK it has gained the Royal Horticultural Society's Award of Garden Merit. The species is native to the Caribbean and South and Central America, but is now a pantropical weed, and can now be found in the Southern United States, South Asia, East Asia, Micronesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstimulus Interval
The interstimulus interval (often abbreviated as ISI) is the temporal interval between the offset of one stimulus to the onset of another. For instance, Max Wertheimer did experiments with two stationary, flashing lights that at some interstimulus intervals appeared to the subject as moving instead of stationary. In these experiments, the interstimulus interval is simply the time between the two flashes. The ISI plays a large role in the phi phenomenon (Wertheimer) since the illusion of motion is directly due to the length of the interval between stimuli. When the ISI is shorter, for example between two flashing lines alternating back and forth, we perceive the change in stimuli to be movement. Wertheimer discovered that the space between the two lines is filled in by our brains and that the faster the lines alternate, the more likely we are to perceive it as one line moving back and forth. When the stimuli move fast enough, this creates the illusion of a moving picture like a movie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
