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REM Phase Of Sleep
Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals (including humans) and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. The core body and brain temperatures increase during REM sleep and skin temperature decreases to lowest values. The REM phase is also known as paradoxical sleep (PS) and sometimes desynchronized sleep or dreamy sleep, because of physiological similarities to waking states including rapid, low-voltage desynchronized brain waves. Electrical and chemical activity regulating this phase seem to originate in the brain stem, and is characterized most notably by an abundance of the neurotransmitter acetylcholine, combined with a nearly complete absence of monoamine neurotransmitters histamine, serotonin and norepinephrine. Experiences of REM sleep are not transferred to permanent memory due to absence of norepinephrine. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Hypnogram
Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain Sensory nervous system, sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity and interactions with the surrounding environment. While sleep differs from wakefulness in terms of the ability to react to Stimulus (physiology), stimuli, it still involves active Human brain, brain patterns, making it more reactive than a coma or disorders of consciousness. Sleep occurs in sleep cycle, repeating periods, during which the body alternates between two distinct modes: rapid eye movement sleep (REM) and Non-rapid eye movement sleep, non-REM sleep. Although REM stands for "rapid eye movement", this mode of sleep has many other aspects, including virtual Rapid eye movement sleep#Muscle, paralysis of the body. Dreams are a succession of images, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallucination
A hallucination is a perception in the absence of an external stimulus that has the compelling sense of reality. They are distinguishable from several related phenomena, such as dreaming ( REM sleep), which does not involve wakefulness; pseudohallucination, which does not mimic real perception, and is accurately perceived as unreal; illusion, which involves distorted or misinterpreted real perception; and mental imagery, which does not mimic real perception, and is under voluntary control. Hallucinations also differ from " delusional perceptions", in which a correctly sensed and interpreted stimulus (i.e., a real perception) is given some additional significance. Hallucinations can occur in any sensory modality— visual, auditory, olfactory, gustatory, tactile, proprioceptive, equilibrioceptive, nociceptive, thermoceptive and chronoceptive. Hallucinations are referred to as multimodal if multiple sensory modalities occur. A mild form of hallucination is known as ... [...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] |
Electroencephalography
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignal, bio signals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex and allocortex. It is typically non-invasive, with the EEG electrodes placed along the scalp (commonly called "scalp EEG") using the 10–20 system (EEG), International 10–20 system, or variations of it. Electrocorticography, involving surgical placement of electrodes, is sometimes called Electrocorticography, "intracranial EEG". Clinical interpretation of EEG recordings is most often performed by visual inspection of the tracing or quantitative EEG, quantitative EEG analysis. Voltage fluctuations measured by the EEG bioamplifier, bio amplifier and electrodes allow the evaluation of normal Brain activity and meditation, brain activity. As the electrical activity monitored by EEG originates in neurons in the underlying Huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurosurgery
Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the specialty (medicine), medical specialty that focuses on the surgical treatment or rehabilitation of disorders which affect any portion of the nervous system including the Human brain, brain, spinal cord, peripheral nervous system, and cerebrovascular system. Neurosurgery as a medical specialty also includes non-surgical management of some neurological conditions. Education and context In different countries, there are different requirements for an individual to legally practice neurosurgery, and there are varying methods through which they must be educated. In most countries, neurosurgeon training requires a minimum period of seven years after graduating from medical school. United Kingdom In the United Kingdom, students must gain entry into medical school. The MBBS qualification (Bachelor of Medicine, Bachelor of Surgery) takes four to six years depending on the student's route. The newly qu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
REM Rebound
REM rebound is the lengthening and increasing frequency and depth of rapid eye movement (REM) sleep which occurs after periods of sleep deprivation. When people have been prevented from experiencing REM, they take less time than usual to attain the REM state. When people are unable to obtain an adequate amount of REM sleep, the pressure to obtain REM sleep builds up. When the subject is able to sleep, they will spend a higher percentage of the night in REM sleep. After early research connected rapid eye movement with dreaming and established that it made up about 20% of normal human sleep, experimenters started depriving test subjects of only REM sleep, to test its unique importance. Every time a subject's electroencephalogram and eye movements indicated the beginning of REM sleep, the experimenter would thoroughly wake them for several minutes. As this "dream deprivation" continued, tendency to initiate REM increased, and the subjects were woken up more and more times each night. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michel Jouvet
Michel Valentin Marcel Jouvet (16 November 1925 – 3 October 2017) was a French neuroscientist and medical researcher. His works, and those of his team, have brought about the discovery of paradoxical sleep (a term he coined) and to its individualisation as the third state of functioning of the brain (1959), to the discovery of its phylogenesis, of its ontogenesis and its main mechanisms. Jouvet was the researcher who first developed the analeptic drug Modafinil. Career Jouvet was Professor of Experimental Medicine at the University of Lyon. He was Director of the Research Unit INSERM U 52 ( Molecular Onirology) and of the Associated Unit UA 1195 of the CNRS (states of vigilance neurobiology). He spent one year in the laboratory of Horace Magoun in Long Beach, California in 1955. He then undertook research in both experimental neurophysiology at the Faculty of Medicine of Lyon and clinical neurophysiology at the Neurological Hospital of Lyon. He described the elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Dement
William is a masculine given name of Germanic origin. It became popular in England after the Norman conquest in 1066,All Things William"Meaning & Origin of the Name"/ref> and remained so throughout the Middle Ages and into the modern era. It is sometimes abbreviated "Wm." Shortened familiar versions in English include Will or Wil, Wills, Willy, Willie, Bill, Billie, and Billy. A common Irish form is Liam. Scottish diminutives include Wull, Willie or Wullie (as in Oor Wullie). Female forms include Willa, Willemina, Wilma and Wilhelmina. Etymology William is related to the German given name ''Wilhelm''. Both ultimately descend from Proto-Germanic ''*Wiljahelmaz'', with a direct cognate also in the Old Norse name ''Vilhjalmr'' and a West Germanic borrowing into Medieval Latin ''Willelmus''. The Proto-Germanic name is a compound of *''wiljô'' "will, wish, desire" and *''helmaz'' "helm, helmet".Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford Un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugene Aserinsky
Eugene Aserinsky (May 6, 1921 – July 22, 1998), a pioneer in sleep research, was a graduate student at the University of Chicago in 1953 when he discovered REM sleep. He was the son of a dentist of Russian–Jewish descent. He made the discovery after hours spent studying the eyelids of sleeping subjects. While the phenomenon was in the beginning more interesting for a fellow of PhD student Aserinsky, William Charles Dement, both Aserinsky and their PhD adviser, Nathaniel Kleitman, went on to demonstrate that this "rapid-eye movement" was correlated with dreaming and a general increase in brain activity. Aserinsky and Kleitman pioneered procedures that have now been used with thousands of volunteers using the electroencephalograph. Because of these discoveries, Aserinsky and Kleitman are generally considered the founders of modern sleep research. Eugene Aserinsky died on July 22, 1998, when his car hit a tree north of San Diego. An autopsy was inconclusive about the caus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nathaniel Kleitman
Nathaniel Kleitman (April 26, 1895 – August 13, 1999) was an American physiologist and sleep researcher who served as Professor Emeritus in Physiology at the University of Chicago. He is recognized as the father of modern sleep research, and is the author of the seminal 1939 book ''Sleep and Wakefulness''. Biography Early life Nathaniel Kleitman was born in Chișinău, also known as Kishinev, the capital of the province of Bessarabia (now Moldova), in 1895 to a Jewish family. He was deeply interested in consciousness and reasoned that he could get insight in consciousness by studying the unconsciousness of sleep. Pogroms drove him to Palestine, and in 1915 he emigrated to the United States as a result of World War I. At the age of twenty, he landed in New York City penniless; in 1923, at age twenty-eight, he had worked his way through City College of New York and earned a PhD from the University of Chicago's Department of Physiology. His thesis was "Studies on the physiolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circulatory System
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek meaning ''heart'', and Latin meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Many invertebrates such as arthropods have an open circulatory system with a he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoregulation
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature as its own body temperature, thus avoiding the need for internal thermoregulation. The internal thermoregulation process is one aspect of homeostasis: a state of dynamic stability in an organism's internal conditions, maintained far from thermal equilibrium with its environment (the study of such processes in zoology has been called physiological ecology). If the body is unable to maintain a normal human body temperature, normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs. Humans may also experience lethal hyperthermia when the wet bulb temperature is sustained above for six hours. Work in 2022 established by experiment that a wet-bulb temperature exceeding 30.55°C caused uncompensab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
