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Wake Maintenance Zone
Second wind (or third wind, fourth wind, etc.), a colloquial name for the scientific term wake maintenance zone, is a sleep phenomenon in which a person, after a prolonged period of staying awake, temporarily ceases to feel drowsy, often making it difficult to fall asleep when exhausted. They are the result of circadian rhythms cycling into a phase of wakefulness. For example, many people experience the effects of a second wind in the early morning even after an entire night without sleep because it is the time when they would normally wake up. While most "winds" coincide with the 24-hour cycle, those experiencing extended sleep deprivation over multiple days have been known to experience a "fifth day turning point". Characteristics The "second wind" phenomenon may have evolved as a survival mechanism as part of the fight-or-flight response, allowing sleep-deprived individuals briefly to function at a higher level than they would without sleep deprivation. Performance enhancemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Clock Human
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary information encoded in genes, which can be transmitted to future generations. Another major theme is evolution, which explains the unity and diversity of life. Energy processing is also important to life as it allows organisms to move, grow, and reproduce. Finally, all organisms are able to regulate their own internal environments. Biologists are able to study life at multiple levels of organization, from the molecular biology of a cell to the anatomy and physiology of plants and animals, and evolution of populations.Based on definition from: Hence, there are multiple subdisciplines within biology, each defined by the nature of their research questions and the tools that they use. Like other scientists, biologists use the scientific meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Debt
Sleep debt or sleep deficit is the cumulative effect of not getting enough sleep. A large sleep debt may lead to mental or physical fatigue, and can adversely affect one's mood, energy and ability to think clearly. There are two kinds of sleep debt: result of partial sleep deprivation, and of total sleep deprivation. Partial sleep deprivation occurs when a person or a lab animal sleeps too little for several days or weeks. Total sleep deprivation, on the other hand, occurs when the subject is being kept awake for at least 24 hours. There is debate in the scientific community over the specifics of sleep debt (see ), and it is not considered to be a disorder. Physiological effects of sleep debt Chronic sleep debt has a substantial health impact on the human body, specifically on metabolic and endocrine functions. A study published in ''The Lancet'' investigated the physiological effects of sleep debt by assessing the sympathovagal balance (an indicator of the sympathetic nerv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circadian Rhythm
A circadian rhythm (), or circadian cycle, is a natural, internal process that regulates the sleep–wake cycle and repeats roughly every 24 hours. It can refer to any process that originates within an organism (i.e., Endogeny (biology), endogenous) and responds to the environment (Entrainment (chronobiology), entrained by the environment). These 24-hour rhythms are driven by a circadian clock, and they have been widely observed in animals, plants, fungi and cyanobacteria. The term ''circadian'' comes from the Latin ''wikt:circa#Latin, circa'', meaning "approximately", and ''dies'', meaning "day". Processes with 24-hour cycles are more generally called diurnal rhythms; diurnal rhythms should not be called circadian rhythms unless they can be confirmed as endogenous, and not environmental. Although circadian rhythms are endogenous, they are adjusted to the local environment by external cues called zeitgebers (German for "time givers"), which include light, temperature and redox cy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypnophobia
The English language, English suffixes -phobia, -phobic, -phobe (from Ancient Greek, Greek φόβος ''phobos'', "fear") occur in technical usage in psychiatry to construct words that describe irrational, abnormal, unwarranted, persistent, or disabling fear as a mental disorder (e.g. agoraphobia), in chemistry to describe chemical aversions (e.g. hydrophobic), in biology to describe organisms that dislike certain conditions (e.g. acidophobia), and in medicine to describe hypersensitivity to a stimulus, usually sensory (e.g. photophobia). In common usage, they also form words that describe dislike or hatred of a particular thing or subject (e.g. homophobia). The suffix is antonymic to -phil-. For more information on the psychiatric side, including how psychiatry groups phobias such as agoraphobia, social phobia, or simple phobia, see phobia. The following lists include words ending in ''-phobia'', and include fears that have acquired names. In some cases, the naming of phobias ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insomnia
Insomnia, also known as sleeplessness, is a sleep disorder in which people have trouble sleeping. They may have difficulty falling asleep, or staying asleep as long as desired. Insomnia is typically followed by daytime sleepiness, low energy, irritability, and a depressed mood. It may result in an increased risk of motor vehicle collisions, as well as problems focusing and learning. Insomnia can be short term, lasting for days or weeks, or long term, lasting more than a month. The concept of the word insomnia has two possibilities: insomnia disorder and insomnia symptoms, and many abstracts of randomized controlled trials and systematic reviews often underreport on which of these two possibilities the word insomnia refers to. Insomnia can occur independently or as a result of another problem. Conditions that can result in insomnia include psychological stress, chronic pain, heart failure, hyperthyroidism, heartburn, restless leg syndrome, menopause, certain medications, and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep State Misperception
Sleep state misperception (SSM) is a term in the International Classification of Sleep Disorders (ICSD) most commonly used for people who mistakenly perceive their sleep as wakefulness,Minecan, Daniela, and Antonio Culebras. http://www.medlink.com/web_content/MLT0003S.asp "Sleep state misperception." ''MedLink Neurology''. Originally published: September 6, 1995. Updated: October 29, 2008.'' though it has been proposed that it be applied to those who severely overestimate their sleep time as wellKushida, Clete A. Handbook of Sleep Disorders'' Informa Health Care, 2008. , . (Page 32) ("positive" sleep state misperception). While most sleepers with this condition will report not having slept in the previous night at all or having slept very little,Insomnia Causes Healthcommunities.com. Original Publication: 01 Dec 2000. Updated: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissociation (psychology)
Dissociation, as a concept that has been developed over time, is a wide array of experiences, ranging from a mild emotional detachment from the immediate surroundings, to a more severe disconnection from physical and emotional experiences. The major characteristic of all dissociative phenomena involves a detachment from reality, rather than a loss of reality as in psychosis. The phenomena are diagnosable under the ''DSM-5'' as a group of disorders as well as a symptom of other disorders through various diagnostic tools. Its cause is believed to be related to neurobiological mechanisms, trauma, anxiety, and psychoactive drugs. Research has further related it to suggestibility and hypnosis, and it is inversely related to mindfulness, which is a potential treatment. History French philosopher and psychologist Pierre Janet (1859–1947) is considered to be the author of the concept of dissociation. Contrary to some conceptions of dissociation, Janet did not believe that dissocia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disinhibition
In psychology, disinhibition is a lack of restraint manifested in disregard of social conventions, impulsivity, and poor risk assessment. Disinhibition affects motor, instinctual, emotional, cognitive, and perceptual aspects with signs and symptoms similar to the diagnostic criteria for mania. Hypersexuality, hyperphagia, and aggressive outbursts are indicative of disinhibited instinctual drives. Clinical concept According to Grafman, et al., "disinhibition" is a lack of restraint manifested in several ways, affecting motor, instinctual, emotional, cognitive, and perceptual aspects with signs and symptoms, e.g., impulsivity, disregard for others and social norms, aggressive outbursts, misconduct and oppositional behaviours, disinhibited instinctual drives including risk taking behaviours and hypersexuality. Disinhibition is a common symptom following brain injury, or lesions, particularly to the frontal lobe and primarily to the orbitofrontal cortex. The neuropsychiatric sequelae f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soporific
Hypnotic (from Greek ''Hypnos'', sleep), or soporific drugs, commonly known as sleeping pills, are a class of (and umbrella term for) psychoactive drugs whose primary function is to induce sleep (or surgical anesthesiaWhen used in anesthesia to produce and maintain unconsciousness, "sleep" is metaphorical as there are no regular sleep stages or cyclical natural states; patients rarely recover from anesthesia feeling refreshed and with renewed energy. The word is also used in art.) and to treat insomnia (sleeplessness). This group of drugs is related to sedatives''. ''Whereas the term sedative describes drugs that serve to calm or relieve anxiety, the term hypnotic generally describes drugs whose main purpose is to initiate, sustain, or lengthen sleep. Because these two functions frequently overlap, and because drugs in this class generally produce dose-dependent effects (ranging from anxiolysis to loss of consciousness), they are often referred to collectively as sedative-hyp ... [...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] |
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] |
Suprachiasmatic Nucleus
The suprachiasmatic nucleus or nuclei (SCN) is a tiny region of the brain in the hypothalamus, situated directly above the optic chiasm. It is responsible for controlling circadian rhythms. The neuronal and hormonal activities it generates regulate many different body functions in a 24-hour cycle. The mouse SCN contains approximately 20,000 neurons. The SCN interacts with many other regions of the brain. It contains several cell types and several different peptides (including vasopressin and vasoactive intestinal peptide) and neurotransmitters. Neuroanatomy The SCN is situated in the anterior part of the hypothalamus immediately dorsal, or ''superior'' (hence supra) to the optic chiasm (CHO) bilateral to (on either side of) the third ventricle. The nucleus can be divided into ventrolateral and dorsolateral portions, also known as the core and shell, respectively. These regions differ in their expression of the clock genes, the core expresses them in response to stimuli whereas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
