Oneirology

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https://en.wikipedia.org/wiki/Oneirology

 

An artist's imaginary depiction of a dream

Oneirology (/ɒnɪˈrɒlədʒi/; from Greek ὄνειρον, oneiron, "dream"; and -λογία, -logia, "the study of") is the scientific study of dreams. Current research seeks correlations between dreaming and current knowledge about the functions of the brain, as well as understanding of how the brain works during dreaming as pertains to memory formation and mental disorders. The study of oneirology can be distinguished from dream interpretation in that the aim is to quantitatively study the process of dreams instead of analyzing the meaning behind them.

History

In the 19th century, two advocates of this discipline were the French sinologists Marquis d'Hervey de Saint Denys and Alfred Maury. The field gained momentum in 1952, when Nathaniel Kleitman and his student Eugene Aserinsky discovered regular cycles. A further experiment by Kleitman and William C. Dement, then another medical student, demonstrated the particular period of sleep during which electrical brain activity, as measured by an electroencephalograph (EEG), closely resembled that of waking, in which the eyes dart about actively. This kind of sleep became known as rapid eye movement (REM) sleep, and Kleitman and Dement's experiment found a correlation of 0.80 between REM sleep and dreaming.

Field of work

Research into dreams includes exploration of the mechanisms of dreaming, the influences on dreaming, and disorders linked to dreaming. Work in oneirology overlaps with neurology and can vary from quantifying dreams, to analyzing brain waves during dreaming, to studying the effects of drugs and neurotransmitters on sleeping or dreaming. Though debate continues about the purpose and origins of dreams, there could be great gains from studying dreams as a function of brain activity. For example, knowledge gained in this area could have implications in the treatment of certain mental illnesses.

Mechanisms of dreaming

Dreaming occurs mainly during REM sleep, and brain scans recording brain activity have witnessed heavy activity in the limbic system and the amygdala during this period. Though current research has reversed the myth that dreaming occurs only during REM sleep, it has also shown that the dreams reported in non-rapid eye movement (NREM) and REM differ qualitatively and quantitatively, suggesting that the mechanisms that control each are different.

During REM sleep, researchers theorize that the brain goes through a process known as synaptic efficacy refreshment. This is observed as brain waves self-firing during sleep, in slow cycles at a rate of around 14 Hz, and is believed to serve the purpose of consolidating recent memories and reinforcing old memories. In this type of brain stimulation, the dreaming that occurs is a by-product of the process.

Stages of sleep

During normal sleep cycles, humans alternate between normal, NREM sleep and REM sleep. The brain waves characteristic of dreaming that are observed during REM sleep are the most commonly studied in dream research because most dreaming occurs during REM sleep.

REM sleep

Main article: REM sleep

 

EEG showing brainwaves during REM sleep

In 1952, Eugene Aserinsky discovered REM sleep while working in the surgery of his PhD advisor. Aserinsky noticed that the sleepers' eyes fluttered beneath their closed eyelids, later using a polygraph machine to record their brain waves during these periods. In one session, he awakened a subject who was wailing and crying out during REM and confirmed his suspicion that dreaming was occurring. In 1953, Aserinsky and his advisor published the ground-breaking study in Science.

Accumulated observation shows that dreams are strongly associated with REM sleep, during which an electroencephalogram shows brain activity to be most like wakefulness. Participant-nonremembered dreams during NREM are normally more mundane in comparison. During a typical lifespan, a human spends a total of about six years dreaming (which is about two hours each night). Most dreams last only 5 to 20 minutes. It is unknown where in the brain dreams originate, if there is a single origin for dreams, if multiple portions of the brain are involved, or what the purpose of dreaming is for the body or mind.

During REM sleep, the release of certain neurotransmitters is completely suppressed. As a result, motor neurons are not stimulated, a condition known as REM atonia. This prevents dreams from resulting in dangerous movements of the body.

Animals have complex dreams and are able to retain and recall long sequences of events while they are asleep. Studies show that various species of mammals and birds experience REM during sleep, and follow the same series of sleeping states as humans.

The discovery that dreams take place primarily during a distinctive electrophysiological state of sleep (REM), which can be identified by objective criteria, led to rebirth of interest in this phenomenon. When REM sleep episodes were timed for their duration and subjects awakened to make reports before major editing or forgetting could take place, it was determined that subjects accurately matched the length of time they judged the dream narrative to occupy with the length of REM sleep that preceded the awakening. This close correlation of REM sleep and dream experience was the basis of the first series of reports describing the nature of dreaming: that it is a regular nightly occurrence, rather than an occasional phenomenon, and that it is a high-frequency activity within each sleep period occurring at predictable intervals of approximately every 60–90 minutes in all humans throughout the life span.

REM sleep episodes and the dreams that accompany them lengthen progressively across the night, with the first episode the shortest, of approximately 10–12 minutes duration, and the second and third episodes increasing to 15–20 minutes. Dreams at the end of the night may last typically 15 minutes, although these may be experienced as several distinct stories due to momentary arousals interrupting sleep as the night ends.

Dream reports can normally be made 50% of the time when an awakening occurs prior to the end of the first REM period. This rate of retrieval is increased to about 99% when awakenings occur during the last REM period of the night. This increase in the ability to recall appears to be related to intensification across the night in the vividness of dream imagery, colors and emotions. The dream story itself in the last REM period is farthest from reality, containing more bizarre elements, and it is these properties, coupled with the increased likelihood of morning waking review to take place, that heighten the chance of recall of the last dream.

Definition of a dream

The definition of dream used in quantitative research is defined through four base components: 1) a form of thinking that occurs under minimal brain direction, external stimuli are blocked, and the part of the brain that recognizes self shuts down; 2) a form of experience that we believed we experience through our senses; 3) something memorable; 4) have some interpretation of experience by self. In summary, a dream, as defined by G. William Domhoff and Adam Schneider, is "a report of a memory of a cognitive experience that happens under the kinds of conditions that are most frequently produced in a state called 'sleep.' "

Commonplace bizarreness in dreaming

Certain kinds of bizarre cognitions, such as disjunctive cognitions and interobjects, are common in dreams.

Interobject

Interobjects, like disjunctive cognitions, are a commonplace bizarreness of dreamlife. Interobjects are a kind of dream condensation that creates a new object that could not occur in waking life. It may have a vague structure that is described as "something between an X and a Y". Hobson dreamt of "a piece of hardware, something like the lock of a door or perhaps a pair of paint-frozen hinges."

Authentic dreaming

Authentic dreams are defined by their tendency to occur "within the realm of experience" and reflect actual memories or experiences the dreamer can relate to. Authentic dreams are believed to be the side effect of synaptic efficacy refreshment that occurs without errors. Research suggests that the brain stimulation that occurs during dreaming authentic dreams is significant in reinforcing neurological pathways, serving as a method for the mind to "rehearse" certain things during sleep.

Illusory dreaming

Illusory dreams are defined as dreams that contain impossible, incongruent, or bizarre content and are hypothesized to stem from memory circuits accumulating efficacy errors. In theory, old memories having undergone synaptic efficacy refreshment multiple times throughout one's lifetime result in accumulating errors that manifest as illusory dreams when stimulated. Qualities of illusory dreaming have been linked to delusions observed in mental disorders. Illusory dreams are believed to most likely stem from older memories that experience this accumulation of errors in contrast to authentic dreams that stem from more recent experiences.

Influences on dreaming

One aspect of dreaming studied is the capability to externally influence the contents of dreams with various stimuli. One such successful connection was made to the olfactory, influencing the emotions of dreams through a smell stimulus. Their research has shown that the introduction of a positive smelling stimulus (roses) induced positive dreams while negative smelling stimulus (rotten eggs) induced negative dreams.

Memories and experience

Though there is much debate within the field about the purpose of dreaming, a leading theory involves the consolidation of memories and experiences that occurs during REM sleep. The electric involuntary stimulus the brain undergoes during sleep is believed to be a basis for a majority of dreaming.

The link between memory, sleep, and dreams becomes more significant in studies analyzing memory consolidation during sleep. Research has shown that NREM sleep is responsible for the consolidation of facts and episodes in contrast to REM sleep that consolidates more emotionally related aspects of memory. The correlation between REM and emotional consolidation could be interpreted as the reason why dreams are of such an emotional nature and produce strong reactions from humans.

Interpersonal attachment

In addition to the conscious role people are aware of memory and experience playing in dreaming, unconscious effects such as health of relationships factor into the types of dreams the brain produces. Of the people analyzed, those suffering from "insecure attachments" were found to dream with more frequency and more vividly than those who were evaluated to have "secure attachments".

Drugs affecting dreaming

Correlations between the usage of drugs and dreaming have been documented, particularly the use of drugs, such as sedatives, and the suppression of dreaming because of drugging effects on the cycles and stages of sleep while not allowing the user to reach REM. Drugs used for their stimulating properties (cocaine, methamphetamine, and ecstasy) have been shown to also decrease the restorative properties of REM sleep and its duration.

Dreaming disorders

Dreaming disorders are difficult to quantify due to the ambiguous nature of dreaming. However, dreaming disorders can be linked to psychological disorders such as post-traumatic stress disorder expressed as nightmares. Research into dreaming also suggests similarity and links in illusory dreaming and delusions.

Post-traumatic stress disorder

Diagnostic symptoms include re-experiencing original trauma(s), by means of flashbacks or nightmares; avoidance of stimuli associated with the trauma; and increased arousal, such as difficulty falling or staying asleep, anger, and hypervigilance.

Links to post-traumatic stress disorder (PTSD) and dreaming have been made in studying the flashbacks or nightmares the victims would suffer. Measurement of the brain waves exhibited by the subjects experiencing these episodes showed great similarity between those of dreaming. The drugs used to treat those suffering from these symptoms of flashbacks and nightmares would suppress not only these traumatic episodes but also any other sort of dreaming function.

Schizophrenia

The symptoms of schizophrenia involve abnormalities in the perception or expression of reality primarily focused on delusions and hallucinations.

The delusions experienced by those with schizophrenia have been likened to the experience of illusory dreams that have come to be interpreted by the subject as actual experiences. Additional research into medication to suppress symptoms of schizophrenia have also shown to influence the REM cycle of those taking the medication and as a result influence the patterns of sleep and dreaming in the subjects.

False awakening

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/False_awakening

A false awakening is a vivid and convincing dream about awakening from sleep, while the dreamer in reality continues to sleep. After a false awakening, subjects often dream they are performing daily morning routine such as showering, cooking, cleaning, eating, and using the bathroom. False awakenings, mainly those in which one dreams that they have awoken from a sleep that featured dreams, take on aspects of a double dream or a dream within a dream. A classic example is the double false awakening of the protagonist in Gogol's Portrait (1835).

Related concepts

Lucidity

A false awakening may occur following a dream or following a lucid dream (one in which the dreamer has been aware of dreaming). Particularly, if the false awakening follows a lucid dream, the false awakening may turn into a "pre-lucid dream", that is, one in which the dreamer may start to wonder if they are really awake and may or may not come to the correct conclusion. In a study by Harvard psychologist Deirdre Barrett, 2,000 dreams from 200 subjects were examined and it was found that false awakenings and lucidity were significantly more likely to occur within the same dream or within different dreams of the same night. False awakenings often preceded lucidity as a cue, but they could also follow the realization of lucidity, often losing it in the process.

Loop

A false awakening loop is when a subject dreams about waking up over and over again, sometimes even up to 10 times or more without knowing which time they are actually awake. At times the individual can perform actions unknowingly. The movie A Nightmare on Elm Street popularized this phenomenon. This phenomenon can be related to that of sleepwalking or carrying out actions in a state of unconsciousness.

Symptoms

Realism and non-realism

Certain aspects of life may be dramatized or out of place in false awakenings. Things may seem wrong: details, like the painting on a wall, not being able to talk or difficulty reading (reportedly, reading in lucid dreams is often difficult or impossible). In some experiences, the subject's senses are heightened, or changed.

Repetition

Because the mind still dreams after a false awakening, there may be more than one false awakening in a single dream. Subjects may dream they wake up, eat breakfast, brush their teeth, and so on; suddenly awake again in bed (still in a dream), begin morning rituals again, awaken again, and so forth. The philosopher Bertrand Russell claimed to have experienced "about a hundred" false awakenings in succession while coming around from a general anesthetic.

Types

Celia Green suggested a distinction should be made between two types of false awakening:

Type 1

Type 1 is the more common, in which the dreamer seems to wake up, but not necessarily in realistic surroundings, that is, not in their own bedroom. A pre-lucid dream may ensue. More commonly, dreamers will believe they have awakened, and then either genuinely wake up in their own bed or "fall back asleep" in the dream.

A common false awakening is a "late for work" scenario. A person may "wake up" in a typical room, with most things looking normal, and realize they overslept and missed the start time at work or school. Clocks, if found in the dream, will show time indicating that fact. The resulting panic is often strong enough to truly awaken the dreamer (much like from a nightmare).

Another common Type 1 example of false awakening can result in bedwetting. In this scenario the dreamer has had a false awakening and while in the state of dream has performed all the traditional behaviors that precede urinating – arising from bed, walking to the bathroom, and sitting down on the toilet or walking up to a urinal. The dreamer may then urinate and suddenly wake up to find they have wet themselves.

Type 2

The type 2 false awakening seems to be considerably less common. Green characterized it as follows:

The subject appears to wake up in a realistic manner but to an atmosphere of suspense. ... The dreamer's surroundings may at first appear normal, and they may gradually become aware of something uncanny in the atmosphere, and perhaps of unwanted [unusual] sounds and movements, or they may "awake" immediately to a "stressed" and "stormy" atmosphere. In either case, the end result would appear to be characterized by feelings of suspense, excitement or apprehension.

Charles McCreery draws attention to the similarity between this description and the description by the German psychopathologist Karl Jaspers (1923) of the so-called "primary delusionary experience" (a general feeling that precedes more specific delusory belief). Jaspers wrote:

Patients feel uncanny and that there is something suspicious afoot. Everything gets a new meaning. The environment is somehow different—not to a gross degree—perception is unaltered in itself but there is some change which envelops everything with a subtle, pervasive and strangely uncertain light. ... Something seems in the air which the patient cannot account for, a distrustful, uncomfortable, uncanny tension invades him.

McCreery suggests this phenomenological similarity is not coincidental and results from the idea that both phenomena, the Type 2 false awakening and the primary delusionary experience, are phenomena of sleep. He suggests that the primary delusionary experience, like other phenomena of psychosis such as hallucinations and secondary or specific delusions, represents an intrusion into waking consciousness of processes associated with stage 1 sleep. It is suggested that the reason for these intrusions is that the psychotic subject is in a state of hyper-arousal, a state that can lead to what Ian Oswald called "micro-sleeps" in waking life.

Other researchers doubt that these are clearly distinguished types, as opposed to being points on a subtle spectrum.

Nightmare

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Nightmare 

 

Nightmare
Specialty	Psychology, Psychiatry
Causes	Stress, Anxiety, Fever

A nightmare, also known as a bad dream, is an unpleasant dream that can cause a strong emotional response from the mind, typically fear but also despair, anxiety, disgust or sadness. The dream may contain situations of discomfort, psychological or physical terror, or panic. After a nightmare, a person will often awaken in a state of distress and may be unable to return to sleep for a short period of time. Recurrent nightmares may require medical help, as they can interfere with sleeping patterns and cause insomnia.

Nightmares can have physical causes such as sleeping in an uncomfortable position or having a fever, or psychological causes such as stress or anxiety. Eating before going to sleep, which triggers an increase in the body's metabolism and brain activity, can be a potential stimulus for nightmares.

The prevalence of nightmares in children (5–12 years old) is between 20 and 30%, and for adults is between 8 and 30%. In common language, the meaning of nightmare has extended as a metaphor to many bad things, such as a bad situation or a scary monster or person.

Etymology

The word nightmare is derived from the Old English mare, a mythological demon or goblin who torments others with frightening dreams. The term has no connection with the Modern English word for a female horse. The word nightmare is cognate with the Dutch term nl:nachtmerrie and German Nachtmahr (dated).

History/Folklore

The sorcerous demons of Iranian mythology known as Divs are likewise associated with the ability to afflict their victims with nightmares. The mare of Germanic and Slavic folklore were thought to ride on people's chests while they sleep, causing nightmares.

Signs and symptoms

Those with nightmares experience abnormal sleep architecture. The impact of having a nightmare during the night has been found to be very similar to that of insomnia. This is thought to be caused by frequent nocturnal awakenings and fear of falling asleep. Nightmare disorder symptoms include repeated awakenings from the major sleep period or naps with detailed recall of extended and extremely frightening dreams, usually involving threats to survival, security, or self-esteem. The awakenings generally occur during the second half of the sleep period.

Classification

According to the International Classification of Sleep Disorders-Third Edition (ICSD-3), the nightmare disorder, together with REM sleep behaviour disorder (RBD) and recurrent isolated sleep paralysis, form the REM-related parasomnias subcategory of the Parasomnias cluster. Nightmares may be idiopathic without any signs of psychopathology or associated with disorders like stress, anxiety, substance abuse, psychiatric illness or PTSD (>80% of PTSD patients report nightmares). As regarding the dream content of the dreams they are usually imprinting negative emotions like sadness, fear or rage. According to the clinical studies the content can include being chased, injury or death of others, falling, natural disasters or accidents. Typical dreams or recurrent dreams may also have some of these topics.

Cause

The Nightmare (Henry Fuseli, 1781) Detroit Institute of Arts

Scientific research shows that nightmares may have many causes. In a study focusing on children, researchers were able to conclude that nightmares directly correlate with the stress in children's lives. Children who experienced the death of a family member or a close friend or know someone with a chronic illness have more frequent nightmares than those who are only faced with stress from school or stress from social aspects of daily life. A study researching the causes of nightmares focuses on patients who have sleep apnea. The study was conducted to determine whether or not nightmares may be caused by sleep apnea, or being unable to breathe. In the nineteenth century, authors believed that nightmares were caused by not having enough oxygen, therefore it was believed that those with sleep apnea had more frequent nightmares than those without it. The results actually showed that healthy people have more nightmares than sleep apnea patients. Another study supports the hypothesis. In this study, 48 patients (aged 20–85 yrs) with obstructive airways disease (OAD), including 21 with and 27 without asthma, were compared with 149 sex- and age-matched controls without respiratory disease. OAD subjects with asthma reported approximately 3 times as many nightmares as controls or OAD subjects without asthma. The evolutionary purpose of nightmares then could be a mechanism to awaken a person who is in danger.

Lucid-dreaming advocate Stephen LaBerge has outlined a possible reason for how dreams are formulated and why nightmares occur. To LaBerge, a dream starts with an individual thought or scene, such as walking down a dimly lit street. Since dreams are not predetermined, the brain responds to the situation by either thinking a good thought or a bad thought, and the dream framework follows from there. If bad thoughts in a dream are more prominent than good thoughts, the dream may proceed to be a nightmare.

There is a view, possibly featured in the story A Christmas Carol, that eating cheese before sleep can cause nightmares, but there is little scientific evidence for this.

Severe nightmares are also likely to occur when a person has a fever, these nightmares are often referred to as fever dreams.

Treatment

Sigmund Freud and Carl Jung seemed to have shared a belief that people frequently distressed by nightmares could be re-experiencing some stressful event from the past. Both perspectives on dreams suggest that therapy can provide relief from the dilemma of the nightmarish experience.

Halliday (1987) grouped treatment techniques into four classes. Direct nightmare interventions that combine compatible techniques from one or more of these classes may enhance overall treatment effectiveness:

• Analytic and cathartic techniques
• Storyline alteration procedures
• Face-and-conquer approaches
• Desensitization and related behavioral techniques

Post-traumatic stress disorder

Recurring post-traumatic stress disorder (PTSD) nightmares in which traumas are re-experienced respond well to a technique called imagery rehearsal. This involves dreamers coming up with alternative, mastery outcomes to the nightmares, mentally rehearsing those outcomes while awake, and then reminding themselves at bedtime that they wish these alternate outcomes should the nightmares reoccur. Research has found that this technique not only reduces the occurrence of nightmares and insomnia, but also improves other daytime PTSD symptoms. The most common variations of imagery rehearsal therapy (IRT) "relate to the number of sessions, duration of treatment, and the degree to which exposure therapy is included in the protocol".

Medication

• Prazosin (alpha-1 blocker) appears useful in decreasing the number of nightmares and the distress caused by them in people with PTSD.
• Risperidone (atypical antipsychotic) at a dosage of 2 mg per day, has been shown in case series to remission of nightmares on the first night.
• Trazodone (antidepressant) has been shown in a case report to treat nightmares associated with a depressed patient.

Trials have included hydrocortisone, gabapentin, paroxetine, tetrahydrocannabinol, eszopiclone, Sodium oxybate, and carvedilol.

Night terror

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Night_terror

 

Night terror
Other names	Sleep terror, pavor nocturnus
Specialty	Psychiatry, Sleep medicine, Clinical Psychology
Symptoms	feelings of panic or dread, sudden motor activity, thrashing, sweating, rapid breathing, increased heart rate
Usual onset	early childhood; symptoms tend to decrease with age
Duration	1 to 10 minutes
Differential diagnosis	epileptic seizure, nightmares

Night terror, also called sleep terror, is a sleep disorder causing feelings of panic or dread and typically occurring during the first hours of stage 3–4 non-rapid eye movement (NREM) sleep and lasting for 1 to 10 minutes. It can last longer, especially in children. Sleep terror is classified in the category of NREM-related parasomnias in the International Classification of Sleep Disorders. There are two other categories: REM-related parasomnias and other parasomnias. Parasomnias are qualified as undesirable physical events or experiences that occur during entry into sleep, during sleep, or during arousal from sleep.

Sleep terrors usually begin in childhood and usually decrease as age increases. Factors that may lead to sleep terrors are young age, sleep deprivation, medications, stress, fever, and intrinsic sleep disorders. The frequency and severity differ among individuals; the interval between episodes can be as long as weeks and as short as minutes or hours. This has created a situation in which any type of nocturnal attack or nightmare may be confused with and reported as a night terror.

Night terrors tend to happen during periods of arousal from delta sleep, or slow-wave sleep. Delta sleep occurs most often during the first half of a sleep cycle, which indicates that people with more delta-sleep activity are more prone to night terrors. However, they can also occur during daytime naps. Night terrors can often be mistaken for confusional arousal.

While nightmares (bad dreams during REM sleep that cause feelings of horror or fear) are relatively common during childhood, night terrors occur less frequently. The prevalence of sleep terrors in general is unknown. The number of small children who experience sleep terror episodes (distinct from sleep terror disorder, which is recurrent and causes distress or impairment) are estimated at 36.9% at 18 months of age and at 19.7% at 30 months. In adults, the prevalence is lower, at only 2.2%. Night terrors have been known since ancient times, although it was impossible to differentiate them from nightmares until rapid eye movement was studied.

Signs and symptoms

Frans Verhas, Inconsolable, 1878 (Royal Museum of Fine Arts Antwerp)

The universal feature of night terrors is inconsolability, very similar to that of a panic attack. During night terror bouts, people are usually described as "bolting upright" with their eyes wide open and a look of fear and panic on their faces. They will often yell, scream, or attempt to speak, though such speech is often incomprehensible. Furthermore, they will usually sweat, exhibit rapid breathing, and have a rapid heart rate (autonomic signs). In some cases, individuals are likely to have even more elaborate motor activity, such as a thrashing of limbs—which may include punching, swinging, or fleeing motions. There is a sense that the individuals are trying to protect themselves and/or escape from a possible threat of bodily injury. Although people may seem to be awake during a night terror, they will appear confused, be inconsolable and/or unresponsive to attempts to communicate with them, and may not recognize others familiar to them. Occasionally, when a person with a night terror is awakened, they will lash out at the one awakening them, which can be dangerous to that individual. Most people who experience this do not remember the incident the next day, although brief dream images or hallucinations may occur and be recalled. Sleepwalking is also common during night-terror bouts, as sleepwalking and night terrors are different manifestations of the same parasomnia. Both children and adults may display behaviour indicative of attempting to escape; some may thrash about or get out of bed and begin walking or running around aimlessly while inconsolable, increasing the risk of accidental injury. The risk of injury to others may be exacerbated by inadvertent provocation by nearby people, whose efforts to calm the individual may result in a physically violent response from the individual as they attempt to escape.

During lab tests, subjects are known to have very high voltages of electroencephalography (EEG) delta activity, an increase in muscle tone, and a doubled or faster heart rate. Brain activities during a typical episode show theta and alpha activity when monitored with an EEG. Episodes can include tachycardia. Night terrors are also associated with intense autonomic discharge of tachypnea, flushing, diaphoresis, and mydriasis—that is, unconscious or involuntary rapid breathing, reddening of the skin, profuse sweating, and dilation of the pupils. Abrupt but calmer arousal from NREM sleep, short of a full night-terror episode, is also common.

In children with night terrors, there is no increased occurrence of psychiatric diagnoses. However, in adults with night terrors there is a close association with psychopathology and mental disorders. There may be an increased occurrence of night terrors—particularly among those with post-traumatic stress disorder (PTSD) and generalized anxiety disorder (GAD). It is also likely that some personality disorders may occur in individuals with night terrors, such as dependent, schizoid, and borderline personality disorders. There have been some symptoms of depression and anxiety that have increased in individuals that have frequent night terrors. Low blood sugar is associated with both pediatric and adult night terrors. A study of adults with thalamic lesions of the brain and brainstem have been occasionally associated with night terrors. Night terrors are closely linked to sleepwalking and frontal lobe epilepsy.

Children

Night terrors typically occur in children between the ages of three and twelve years, with a peak onset in children aged three and a half years old. An estimated 1–6% of children experience night terrors. Children of both sexes and all ethnic backgrounds are affected equally. In children younger than three and a half years old, peak frequency of night terrors is at least one episode per week(can also be more up to 3-4 in rare cases). Among older children, peak frequency of night terrors is one or two episodes per month. The children will most likely have no recollection of the episode the next day. Pediatric evaluation may be sought to exclude the possibility that the night terrors are caused by seizure disorders or breathing problems. Most children will outgrow sleep terrors.

Adults

Night terrors in adults have been reported in all age ranges. Though the symptoms of night terrors in adolescents and adults are similar, the cause, prognosis and treatment are qualitatively different. These night terrors can occur each night if the individual does not eat a proper diet, get the appropriate amount or quality of sleep (e.g. sleep apnea), is enduring stressful events, or if he or she remains untreated. Adult night terrors are much less common, and often respond to treatments to rectify causes of poor quality or quantity of sleep. Night terrors are classified as a mental and behavioral disorder in the ICD. A study done about night terrors in adults showed that other psychiatric symptoms were prevalent in most patients experiencing night terrors hinting at the comorbidity of the two. There is some evidence of a link between night terrors and hypoglycemia.

When a night terror happens, it is typical for a person to wake up yelling and kicking and to be able to recognize what he or she is saying. The person may even run out of the house (more common among adults) which can then lead to violent actions. It has been found that some adults who have been on a long-term intrathecal clonidine therapy show side effects of night terrors, such as feelings of terror early in the sleep cycle. This is due to the possible alteration of cervical/brain clonidine concentration. In adults, night terrors can be symptomatic of neurological disease and can be further investigated through an MRI procedure.

Causes

There is some evidence that a predisposition to night terrors and other parasomnias may be congenital. Individuals frequently report that past family members have had either episodes of sleep terrors or sleepwalking. In some studies, a ten-fold increase in the prevalence of night terrors in first-degree biological relatives has been observed—however, the exact link to inheritance is not known. Familial aggregation has been found suggesting that there is an autosomal mode of inheritance. In addition, some laboratory findings suggest that sleep deprivation and having a fever can increase the likelihood of a night terror episode occurring. Other contributing factors include nocturnal asthma, gastroesophageal reflux, central nervous system medications, and a constricted nasal passage. Special consideration must be used when the subject with narcolepsy, as there may be a link. There have been no findings that show a cultural difference between manifestations of night terrors, though it is thought that the significance and cause of night terrors differ within cultures.

Also, older children and adults provide highly detailed and descriptive images associated with their sleep terrors compared to younger children, who either cannot recall or only vaguely remember. Sleep terrors in children are also more likely to occur in males than females; in adults, the ratio between sexes is equal. A longitudinal study examined twins, both identical and fraternal, and found that a significantly higher concordance rate of night terror was found in identical twins than in fraternal.

Though the symptoms of night terrors in adolescents and adults are similar, their causes, prognoses, and treatments are qualitatively different. There is some evidence that suggests that night terrors can occur if the individual does not eat a proper diet, does not get the appropriate amount or quality of sleep (e.g., because of sleep apnea), or is enduring stressful events. Adults who have experienced sexual abuse are more likely to receive a diagnosis of sleep disorders, including night terrors. Overall, though, adult night terrors are much less common and often respond best to treatments that rectify causes of poor quality or quantity of sleep.

Diagnosis

The DSM-5 diagnostic criteria for sleep terror disorder requires:

• Recurrent periods where the individual abruptly but not completely wakes from sleep, usually occurring during the first third major period of sleep.
• The individual experiences intense fear with a panicky scream at the beginning and symptoms of autonomic arousal, such as increased heart rate, heavy breathing, and increased perspiration. The individual cannot be soothed or comforted during the episode.
• The individual is unable or almost unable to remember images of the dream (only a single visual scene for example).
• The episode is completely forgotten.
• The occurrence of the sleep terror episode causes clinically significant distress or impairment in the individual's functioning.
• The disturbance is not due to the effects of a substance, general medical condition or medication.
• Coexisting mental or medical disorders do not explain the episodes of sleep terrors.

Differential diagnosis

Night terrors are distinct from nightmares. In fact, in nightmares there are almost never vocalization or agitation, and if there are any, they are less strong in comparison to night terrors. In addition, nightmares appear ordinarily during REM sleep in contrast to night terrors, which occur in NREM sleep. Finally, individuals with nightmares can wake up completely and easily and have clear and detailed memories of their dreams.

A distinction between night terrors and epileptic seizure is required. Indeed, an epileptic seizure could happen during the night but also during the day. To make the difference between both of them, an EEG can be done and if there are some anomalies on it, it would rather be an epileptic seizure.

Assessment

The assessment of sleep terrors is similar to the assessment of other parasomnias and must include:

• When the episode occurs during the sleep period
• Age of onset
• How often these episodes occur (frequency) and how long they last for (duration)
• Description of the episode, including behavior, emotions, and thoughts during and after the event
• How responsive the patient is to external stimuli during the episode
• How conscious or aware the patient is, when awakened from an episode
• If the episode is remembered afterwards
• The triggers or precipitating factors
• Sleep–wake pattern and sleep environment
• Daytime sleepiness
• Other sleep disorders that might be present
• Family history for NREM parasomnias and other sleep disorders
• Medical, psychiatric, and neurological history
• Medication and substance use history

Additionally, a home video might be helpful for a proper diagnosis. A polysomnography in the sleep laboratory is recommended for ruling out other disorders, however, sleep terrors occur less frequently in the sleep laboratory than at home and a polysomnography can therefore be unsuccessful at recording the sleep terror episode.

Treatment

In most children, night terrors eventually subside and do not need to be treated. It may be helpful to reassure the child and their family that they will outgrow this disorder.

The duration of one episode is mostly brief but it may last longer if parents try to wake up the child. Awakening the child may make their agitation stronger. For all these reasons, it is important to let the sleep terror episode fade away and to just be vigilant in order for them not to fall to the ground.

Considering an episode could be violent, it may be advisable to secure the environment in which the child sleeps. Windows should be closed and potentially dangerous items should be removed from the bedroom, and additionally, alarms can be installed and the child placed in a downstairs bedroom.

There is some evidence to suggest that night terrors can result from lack of sleep or poor sleeping habits. In these cases, it can be helpful to improve the amount and quality of sleep which the child is getting. It is also important to have a good sleep hygiene, if a child has night terrors parents could try to change their sleep hygiene. Another option could be to adapt child's naps so that they are not too long or too short. Then, excessive stress or conflicts in a child's life could also have an impact on their sleep too, so to have some strategies to cope with stress combined with psychotherapy could decrease the frequency of the episodes. A polysomnography can be recommended if the child continues to have a lot of night terror episodes.

Hypnosis could be efficient. Sleepers could become less sensitive to their sleep terrors.

One technique is to wake up just before the sleep terrors begin. When they appear regularly, this method can prevent their appearance.

Psychotherapy or counseling might be helpful in some cases.

If all these methods are not enough, benzodiazepines (such as diazepam) or tricyclic antidepressants may be used; however, medication is only recommended in extreme cases. Widening the nasal airway by surgical removal of the adenoid was previously considered and demonstrated to be effective; nowadays, however, invasive treatments are generally avoided.

Research

A small study of paroxetine found some benefit.

Another small trial found benefit with L-5-hydroxytryptophan (L-5-HTP).

Time preference

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Time_preference

In economics, time preference (or time discounting, delay discounting, temporal discounting, long-term orientation) is the current relative valuation placed on receiving a good or some cash at an earlier date compared with receiving it at a later date.

Time preferences are captured mathematically in the discount function. The higher the time preference, the higher the discount placed on returns receivable or costs payable in the future.

One of the factors that may determine an individual's time preference is how long that individual has lived. An older individual may have a lower time preference (relative to what they had earlier in life) due to a higher income and to the fact that they have had more time to acquire durable commodities (such as a college education or a house). As future is inherently uncertain, risk preferences also affect time preferences. 

Example

A practical example: Jim and Bob go out for a drink but Jim has no money so Bob lends Jim $10. The next day Jim visits Bob and says, "Bob, you can have $10 now, or I will give you $15 when I get paid at the end of the month." Bob's time preference will change depending on his trust in Jim, whether he needs the money now, or if he thinks he can wait; or if he'd prefer to have $15 at the end of the month rather than $10 now. Present and expected needs, present and expected income affect one's time preference.

Neoclassical views

In the neoclassical theory of interest due to Irving Fisher, the rate of time preference is usually taken as a parameter in an individual's utility function which captures the trade off between consumption today and consumption in the future, and is thus exogenous and subjective. It is also the underlying determinant of the real rate of interest. The rate of return on investment is generally seen as return on capital, with the real rate of interest equal to the marginal product of capital at any point in time. Arbitrage, in turn, implies that the return on capital is equalized with the interest rate on financial assets (adjusting for factors such as inflation and risk). Consumers, who are facing a choice between consumption and saving, respond to the difference between the market interest rate and their own subjective rate of time preference ("impatience") and increase or decrease their current consumption according to this difference. This changes the amount of funds available for investment and capital accumulation, as in for example the Ramsey growth model.

In the long run steady state, consumption's share in a person's income is constant which pins down the rate of interest as equal to the rate of time preference, with the marginal product of capital adjusting to ensure this equality holds. It is important to note that in this view, it is not that people discount the future because they can receive positive interest rates on their savings. Rather, the causality goes in the opposite direction; interest rates must be positive in order to induce impatient individuals to forgo current consumptions in favor of future.

Austrian Economics

Time preference is a key component of the Austrian School of economics, it is used to understand the relationship between saving, investment and interest rates. According to the Misesian branch of the school: In acting, an actor invariably aims to substitute a more satisfactory for a less satisfactory state of affairs and thus demonstrates a preference for more rather than fewer goods. Moreover, he invariably consider when in the future his goals will be reached, i.e., the time necessary to accomplish them, as well as a good's duration of serviceability. Thus, he also demonstrates a universal preference for earlier over later goods, and for more over less durable ones. This is the phenomenon of time preference. Every actor requires some amount of time to attain his goal, and since man must always consume something and cannot entirely stop consuming while he is alive, time is always scarce. Thus, ceteris paribus, present or earlier goods are, and must invariably be, valued more highly than future or later ones. In fact, if man were not constrained by time preference and if the only constraint operating on him were that of preferring more over less, he would invariably choose those production processes which yielded the largest output per input, regardless of the length of time needed for these methods to bear fruit.^[6]

To enjoy greater consumption, man must extend his productivity first. Since acquiring the increased productivity comes with a cost—namely, time spent away from using the old method of production and consumption—there must be some means of paying that cost. This is the role of savings. Some people have refrained from consumption in the past so that others can be sustained and create the new structure.

Savings remain key to this process of capital construction, and it is the time preference, that manifests itself in savings. Time preference is the extent to which people value current consumption over future consumption. If people enjoy current consumption so much, that the promise of an increased future consumption cannot bring them to save (and sacrifice the current level of consumption), the production will not be improved.

The thrust of the Austrian Business Cycle Theory is that credit inflation distorts this process, by making it appear that more means exist for current production than are actually sustainable. Since this is in fact an illusion, the endeavors of entrepreneurs to create a structure of production not reflecting actual consumer time preferences (as manifested in available savings for the purchase of producer goods) must end in failure.

Time-Preference Theory of Interest

The Austrian school rejects the classical view of capital, which says interest rates are determined by the supply and demand of capital. The Austrian school holds that interest rates are determined by the subjective decision of individuals to spend money now or in the future. In other words, interest rates are determined by the time preference of borrowers and lenders. For example, an increase in the rate of saving suggests that consumers are putting off present consumption and that more resources (and money) will be available in the future.

Austrian economist Eugen von Böhm-Bawerk, who expounded on the theory in his book Capital and Interest, believes that the value of goods decreases as the length of time needed for their completion increases, even when their quantity, quality, and nature remain the same. Böhm-Bawerk names three reasons for the inherent difference in value between present and future goods: the tendency, in a healthy economy, for the supply of goods to grow over time; the tendency of consumers to underestimate their future needs; and the preference of entrepreneurs to initiate production with materials presently available, rather than waiting for future goods to appear.

Temporal discounting

Temporal discounting (also known as delay discounting, time discounting) is the tendency of people to discount rewards as they approach a temporal horizon in the future or the past (i.e., become so distant in time that they cease to be valuable or to have additive effects). To put it another way, it is a tendency to give greater value to rewards as they move away from their temporal horizons and towards the "now". For instance, a nicotine deprived smoker may highly value a cigarette available any time in the next 6 hours but assign little or no value to a cigarette available in 6 months.

Regarding terminology, from Frederick et al. (2002):

We distinguish time discounting from time preference. We use the term time discounting broadly to encompass any reason for caring less about a future consequence, including factors that diminish the expected utility generated by a future consequence, such as uncertainty or changing tastes. We use the term time preference to refer, more specifically, to the preference for immediate utility over delayed utility.

This term is used in intertemporal economics, intertemporal choice, neurobiology of reward and decision making, microeconomics and recently neuroeconomics. Traditional models of economics assumed that the discounting function is exponential in time leading to a monotonic decrease in preference with increased time delay; however, more recent neuroeconomic models suggest a hyperbolic discount function which can address the phenomenon of preference reversal. Temporal discounting is also a theory particularly relevant to the political decisions of individuals, as people often put their short term political interests before the longer term policies. This can be applied to the way individuals vote in elections but can also apply to how they contribute to societal issues like climate change, that is primarily a long term threat and therefore not prioritised.

Assessing temporal discounting

Offered a choice of $100 today and $100 in one month, individuals will most likely choose the $100 now. However, should the question change to having $100 today, or $1,000 in one month, individuals will most likely choose the $1,000 in one month. The $100 can be conceptualized as a Smaller Sooner Reward (SSR), and the $1,000 can be conceptualized as a Larger Later Reward (LLR). Researchers who study temporal discounting are interested in the point in time in which an individual changes their preference for the SSR to the LLR, or vice versa. For example, although an individual may prefer $1,000 in one month over $100 now, they may switch their preference to the $100 if the delay to the $1,000 is increased to 60 months (5 years). This means that this individual values $1,000 after a delay of 60 months less than $100 now. The trick is to find the point in time in which the individual values the LLR and the SSR as being equivalent. That is known as the indifference point. Preferences can be measured by asking people to make a series of choices between immediate and delayed payoffs, where the delay period and the payoff amounts are varied.

Origin of differences in time preference across countries

Oded Galor and Omer Ozak explore the roots of observed differences in time preference across nations. They establish that pre-industrial agricultural characteristics that were favorable to higher return to agricultural investment triggered a process of selection, adaptation, and learning that brought about a higher prevalence of long-term orientation. These agricultural characteristics are associated with contemporary economic and human behavior such as technological adoption, education, saving, and smoking.

Historical understanding of time preference theory in relation to interest rates

The Catholic scholastic philosophers firstly brought up sophisticated explanations and justifications of return on capital, including risk and the opportunity cost of profit forgone, associated with the discount factor. However, they failed to interpret the interest on a riskless loan and hence denounced the time preference discounter as sinful and usurious.

Later, Conrad Summenhart, a theologian at the University of Tübingen, used time preference to explain the discount loans, where the lenders won't profit usuriously from the loans as the borrowers would accept the price the lenders ask. A half-century later, Martin de Azpilcueta Navarrus, a Dominican canon lawyer and monetary theorist at the University of Salamanca, held the view that present goods, such as money, will naturally be worth more on the market than future goods (money). At about the same time, Gian Francesco Lottini da Volterra, an Italian humanist and politician, discovered time preference and contemplated time preference as an overestimation of "a present" that can be grasped immediately by the senses. Two centuries later, Ferdinando Galiani, a Neapolitan abbot, used an analogy to point out that just similar to the exchange rate, the interest rate links and equates the present value to the future value, and under people's subjective mind, these two physically non-identical items should be equal.

These scattered thoughts and progression of theories inspired Anne Robert Jacques Turgot, a French statesman, to generate a full-scale time preference theory: what must be compared in a loan transaction is not the value of money lent with the value repaid, but rather the ‘value of the promise of a sum of money compared to the value of money available now; in addition, he analyzed the relation between money supply and interest rates: If money supply increases and people with insensitive time preference receive the money, then these people tend to hoard money for savings instead of going for consumptions, which will cause interest rates to fall while prices to rise. This helps to explain why contemporary interest rates have tended to fall due to the European thrifty spirit.

Digital detox

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Digital_detox 

A digital detox is a time without digital devices, such as smartphones

A digital detox is a period of time when a person voluntarily refrains from using digital devices such as smartphones, computers, and social media platforms. This form of detoxification has gained popularity, as individuals have increased their time spent on digital devices and the Internet.

Background

See also: Digital media use and mental health, Problematic social media use, and Problematic smartphone use

A 2015 survey conducted by Deloitte found that around 59% of smartphone users check a social media platform in the five minutes prior to going to bed, and within 30 minutes of waking up.

Motivations

Motivations to start a digital detox include:

• Concern about developing addictive behavior that some identify as an Internet addiction disorder
• Aiming to reduce stress and anxiety caused by the over-use of technology
• Re-focusing offline social interactions and actions
• Re-connecting with nature
• Increasing mindfulness
• Improving one's learning ability by decreasing distractions and eliminating multi-tasking

Potential health effects

Smartphone usage can disturb sleep and cause vision problems

The extended overuse of technology has been found to reduce quality of sleep, cause eye strain and vision problems, as well as lead to the increased occurrence of migraine headaches. A previous research survey of over 7,000 participants found that approximately 70% of those who use technology with screens have experienced "digital eye strain as a result of the growing use of [screen possessing technological devices]".

Research on the effects of popular technological devices such as cellphones and computers on sleep has suggested that the light emitted from screens may suppress the production of the hormone melatonin, an important regulatory biochemical that controls the duration and character of sleep cycles.

Potential effects on relationships

A study of 145 American adults recruited through MTurk in 2016 suggested that marital satisfaction can be lowered if either partner "snubs" the other in favor of using a cellphone. The act was also associated with a higher incidence of depression and a reported lower satisfaction with life. The self-reported attachment styles of the participants were seen to have an effect such that individuals with attachment anxiety reported a higher degree of cell phone conflict.

Another study suggested that the visible presence of mobile devices during conversations may have a limiting effect on the sense of connection felt between those involved in the conversation as well as the overall quality of the conversation.

Social media detoxification

A subset of digital detox is social media detox, which is a period of time when individuals voluntarily stay away from social media. In academic research, social media detoxification is commonly referred to as the "non-use of social media", and falls under the umbrella of "Digital Detox", with a focus specifically on unplugging from social media.

A 2019 Pew Research Center study found that 69% of adults in the United States used Facebook, 73% used YouTube, and 37% used Instagram. A 2012 study found that around 60% of Facebook users have made a conscious effort to voluntarily take a break from Facebook for a time period of several weeks or more. This has been referred to as "media refusal", with non-users known as "social media rejectors" who once used social media but have now voluntarily given it up for various reasons.

Methods

A subset of a digital detox is a social media detox, in which an individual voluntarily keeps off of social media platforms. Motivations for performing only a subset of a digital detox could be attributed to the total time spent on social media platforms and the related psychological effects.  The use of social media can lead to internet addiction and decrease productivity which is why celebrities such as Ed Sheeran and Kendall Jenner have undergone a social media detox and influenced others to do one as well. Comedian Ari Shaffir gained attention for refusing to use a smartphone after concerns about spending too much time on it, especially on social media. Many social media users will also visit their platforms multiple times per day, with 68% of Snapchat users and 50% of Facebook users doing so. Based on a 2019 Pew Research Center study, 73% of adults in the United States use YouTube, 37% use Instagram and 69% use Facebook with around 60% of Facebook users making an effort to undergo a social media detoxification.

Most experts agree that moderation is a much more effective method of detoxification than fully forgoing technology. One way of curbing overuse of digital devices is to allocate some of the uses of a smartphone to non-digital means. In 2019 Google announced a "paper phone" which can contain daily agendas, directions, and other uses so that people rely less on their smartphone.

Designated 'sacred spaces' wherein smartphone usage is strictly prohibited can help.

Recently, the tourism industry has found a niche market for 'digital detox travel packages' where tourists are disconnected from their Information and communications technology by traveling to remote areas. A study from University of Nottingham Ningbo China found that the biggest motivators for embarking on a digital detox holiday include mindfulness, technostress, relaxation, and self-expression.

Criticism

In the 2010s, technology and social media became an integral aspect of everyday life, and thus the decision to refrain from using technology or social media has become a conscious lifestyle choice reflecting the desire for selective and reversible disconnection. In the digital age, social media plays a vital role in building social capital, maintaining connections, and managing impressions. Scholars have argued for the importance of maintaining a certain level of distraction that social media can provide for a balanced state of body and mind, and some scholars have even argued that social media is necessary and should not be completely cut out. That being said, many scholars believe that the moderation of social media is essential, primarily due to social media platforms' goal of encouraging constant use with likes, notifications, and infinite scrolling. To lessen the effects of these addictive features social media platforms such as Instagram have begun to explore alternative methods, such as making likes on a user's post invisible to the user, to shift the focus away from constant notifications and likes.

Some companies have even launched movements against technology addiction. For example, in October 2019, Google released Paper Phone, a Google product consisting of a printed piece of paper folded into eighths that contains relevant information to your day much like a daily planner. The motive behind the project was to provide the utility of a smartphone in a simplistic and less dynamic delivery. Other projects have focused on building second phones with less functionality, or putting human nature and design above technology. Some critics disagree with Google's approach to the digital detox phenomenon, however, and instead argue that harmony between technology use and well-being can be achieved. These critics suggest that the best way to digitally detox is to be mindful of the amount of time that is being spent on a digital device.