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Chronotype
A chronotype is the behavioral manifestation of underlying circadian rhythm's myriad of physical processes. A person's chronotype is the propensity for the individual to sleep at a particular time during a 24-hour period. ''Eveningness'' (delayed sleep period; most active and alert in the evening) and ''morningness'' (advanced sleep period; most active and alert in the morning) are the two extremes with most individuals having some flexibility in the timing of their sleep period. However, across development there are changes in the propensity of the sleep period with pre-pubescent children preferring an advanced sleep period, adolescents preferring a delayed sleep period and many elderly preferring an advanced sleep period. The causes and regulation of chronotypes, including developmental change, individual propensity for a specific chronotype, and flexible versus fixed chronotypes have yet to be determined. However, research is beginning to shed light on these questions, such as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Till Roenneberg
Till Roenneberg (born 4 May 1953) is a professor of chronobiology at the Institute of Medical Psychology at Ludwig Maximilian University of Munich, Ludwig-Maximilian University (LMU) in Munich, Germany. Roenneberg, in collaboration with Martha Merrow, explores the impact of light on human circadian rhythms, focusing on aspects such as chronotypes and social jet lag in relation to health benefits. Life Roenneberg was born in Munich, Germany. He began working with Jürgen Aschoff at the age of 17. Roenneberg attended both the University College London and Ludwig Maximilian University of Munich where he began by studying physics. He switched to medicine in order to focus on the science of the human body, but ended up studying biology. As a postdoctoral fellow, he studied again under Jürgen Aschoff, studying annual rhythms in the body, then moved to the United States to study the cellular basis of biological clocks under Woody Hastings at Harvard University. In 1991, he began ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep
Sleep is a sedentary state of mind and body. It is characterized by altered consciousness, relatively inhibited sensory activity, reduced muscle activity and reduced interactions with surroundings. It is distinguished from wakefulness by a decreased ability to react to stimuli, but more reactive than a coma or disorders of consciousness, with sleep displaying different, active brain patterns. Sleep occurs in repeating periods, in which the body alternates between two distinct modes: REM sleep and non-REM sleep. Although REM stands for "rapid eye movement", this mode of sleep has many other aspects, including virtual 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. During sleep, most of the body's systems are in an anabolic state, helping to restore the immune, nervous, skeletal, and muscular systems; these are vital processes that maintain mood, memory, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lark (person)
A lark, early bird, morning person, or (in Scandinavian countries) an A-person, is a person who usually gets up early in the morning and goes to bed early in the evening. The term relates to the birds known as larks, which are known to sing before dawn. Human "larks" may sleep from around 10 p.m. to 6 a.m. (or earlier), and tend to feel most energetic just after they get up in the morning. They are thus well-suited for working the day shift. The opposite of the lark is the owl, often awake at night. A person called a ''night owl'' is someone who usually stays up late and may feel most awake in the evening and at night. Researchers have traditionally used the terms morningness and ''eveningness'' to describe these two chronotypes. Charting chronotypes Till Roenneberg, a chronobiologist in Munich, has mapped the circadian rhythms of more than 200,000 people. Biological processes, including sleep-wake patterns, that display an oscillation of about 24 hours are called circadian rhyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morningness–eveningness Questionnaire
The morningness–eveningness questionnaire (MEQ) is a self-assessment questionnaire developed by researchers James A. Horne and Olov Östberg in 1976. Its main purpose is to measure whether a person's circadian rhythm (biological clock) produces peak alertness in the morning, in the evening, or in between. The original study showed that the subjective time of peak alertness correlates with the time of Thermoregulation#Variations due to circadian rhythms, peak body temperature; morning types (Lark (person), early birds) have an earlier temperature peak than evening types (Night owl (person), night owls), with intermediate types having temperature peaks between the morning and evening chronotype groups. The MEQ is widely used in psychological and medical research and has been professionally cited more than 4,000 times. MEQ questions The standard MEQ consists of 19 multiple-choice questions, each having four or five response options. Some example questions are: Responses to the q ... [...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 physiolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Night Owl (person)
A night owl, evening person or simply owl, is a person who tends to stay up until late at night, or to the very early hours of the morning. Night owls who are involuntarily unable to fall asleep for several hours after a normal time may have delayed sleep phase disorder. The opposite of a night owl is an early bird – a lark as opposed to an owl – which is someone who tends to begin sleeping at a time that is considered early and also wakes early. Researchers traditionally use the terms ''morningness'' and eveningness for the two chronotypes or diurnality and nocturnality in animal behavior. In several countries, especially in Scandinavia, early birds are called ''A-people'' and a night owl is called a B-person. History While staying up after dark was considered a negative trait, this changed in 17th and 18th century Europe (and subsequently spread beyond) due to the development and implementation of artificial lighting: more domestic lights, added street lighting, and adap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circadian Rhythm Sleep Disorder
Circadian rhythm sleep disorders (CRSD), also known as circadian rhythm sleep-wake disorders (CRSWD), are a family of sleep disorders which affect the timing of sleep. CRSDs arise from a persistent pattern of sleep/wake disturbances that can be caused either by dysfunction in one's biological clock system, or by misalignment between one's endogenous oscillator and externally imposed cues. As a result of this mismatch, those affected by circadian rhythm sleep disorders have a tendency to fall asleep at unconventional time points in the day. These occurrences often lead to recurring instances of disturbed rest, where individuals affected by the disorder are unable to go to sleep and awaken at "normal" times for work, school, and other social obligations. Delayed sleep phase disorder, advanced sleep phase disorder, non-24-hour sleep–wake disorder and irregular sleep–wake rhythm disorder represents the four main types of CRSD. Overview Humans, like most living organisms, have v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronobiology
Chronobiology is a field of biology that examines timing processes, including periodic (cyclic) phenomena in living organisms, such as their adaptation to solar- and lunar-related rhythms. These cycles are known as biological rhythms. Chronobiology comes from the ancient Greek χρόνος (''chrónos'', meaning "time"), and biology, which pertains to the study, or science, of life. The related terms ''chronomics'' and ''chronome'' have been used in some cases to describe either the molecular mechanisms involved in chronobiological phenomena or the more quantitative aspects of chronobiology, particularly where comparison of cycles between organisms is required. Chronobiological studies include but are not limited to comparative anatomy, physiology, genetics, molecular biology and behavior of organisms related to their biological rhythms. Other aspects include epigenetics, development, reproduction, ecology and evolution. The subject Chronobiology studies variations of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RGS16
Regulator of G-protein signaling 16 is a protein that in humans is encoded by the ''RGS16'' gene. Function The protein encoded by this gene belongs to the 'regulator of G protein signaling' family. It inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits. It also may play a role in regulating the kinetics of signaling in the phototransduction cascade. Interactions RGS16 has been shown to interact with GNAQ Guanine nucleotide-binding protein G(q) subunit alpha is a protein that in humans is encoded by the ''GNAQ'' gene. Together with GNA11 (its paralogue), it functions as a Gq alpha subunit. Function Guanine nucleotide-binding proteins are a fam ... and GNAI3. References Further reading * * * * * * * * * * * * * * * * * * * * * * * * * {{PDB Gallery, geneid=6004 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-protein
G proteins, also known as guanine nucleotide-binding proteins, are a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. Their activity is regulated by factors that control their ability to bind to and hydrolyze guanosine triphosphate (GTP) to guanosine diphosphate (GDP). When they are bound to GTP, they are 'on', and, when they are bound to GDP, they are 'off'. G proteins belong to the larger group of enzymes called GTPases. There are two classes of G proteins. The first function as monomeric small GTPases (small G-proteins), while the second function as heterotrimeric G protein complexes. The latter class of complexes is made up of ''alpha'' (α), ''beta'' (β) and ''gamma'' (γ) subunits. In addition, the beta and gamma subunits can form a stable dimeric complex referred to as the beta-gamma complex . Heterotrimeric G proteins located within the cell are activa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melatonin
Melatonin is a natural product found in plants and animals. It is primarily known in animals as a hormone released by the pineal gland in the brain at night, and has long been associated with control of the sleep–wake cycle. In vertebrates, melatonin is involved in synchronizing circadian rhythms, including sleep–wake timing and blood pressure regulation, and in control of seasonal rhythmicity including reproduction, fattening, moulting and hibernation. Many of its effects are through activation of the melatonin receptors, while others are due to its role as an antioxidant. In plants, it functions to defend against oxidative stress. It is also present in various foods. Melatonin was discovered in 1958. In addition to its role as a natural hormone, melatonin is used as a dietary supplement and medication in the treatment of sleep disorders such as insomnia and circadian rhythm sleep disorders; for information on melatonin as a supplement and medication, see the melatoni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Adenosine Monophosphate
Cyclic adenosine monophosphate (cAMP, cyclic AMP, or 3',5'-cyclic adenosine monophosphate) is a second messenger important in many biological processes. cAMP is a derivative of adenosine triphosphate (ATP) and used for intracellular signal transduction in many different organisms, conveying the cAMP-dependent pathway. History Earl Sutherland of Vanderbilt University won a Nobel Prize in Physiology or Medicine in 1971 "for his discoveries concerning the mechanisms of the action of hormones", especially epinephrine, via second messengers (such as cyclic adenosine monophosphate, cyclic AMP). Synthesis Cyclic adenosine monophosphate, AMP is synthesized from Adenosine triphosphate, ATP by adenylate cyclase located on the inner side of the plasma membrane and anchored at various locations in the interior of the cell. Adenylate cyclase is ''activated'' by a range of signaling molecules through the activation of adenylate cyclase stimulatory G (Gs alpha subunit, Gs)-protein-coupled recep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
