I Can’t Sleep - Sleep | Gentle Bedtime Reading for Restful Nights

Episode Date: August 16, 2019

Drift off with calm bedtime reading about sleep to ease insomnia and restless nights. This soothing episode explores the science and mystery of sleep, from its vital role in health and memory to the cycles of dreaming and rest. Benjamin’s peaceful cadence transforms learning into relaxation, helping you settle the mind and body. With no whispering or hypnosis—just calm, fact-filled storytelling—you’ll discover how sleep restores balance while feeling your own rest deepen. Press play, relax, and let the topic of sleep gently guide you into slumber. Want More? Request a Topic: https://www.icantsleeppodcast.com/request-a-topic Ad-Free Episodes: https://icantsleep.supportingcast.fm/ Shop Sleep-Friendly Products: https://www.icantsleeppodcast.com/sponsors Join the Discussion on Discord: https://discord.gg/myhGhVUhn7 This content is derived from the Wikipedia article on Sleep, available under the Creative Commons Attribution-ShareAlike (CC BY-SA) license. Read the full article: Wikipedia – Sleep. Happy sleeping! Learn more about your ad choices. Visit megaphone.fm/adchoices

You're listening to a Glassbox media podcast. What if I told you that most of the modern day self-help advice you've been hearing could actually make you worse? The key to a better life isn't about feel-good gimmicks that sound catchy. The Mentally Stronger Podcast gives you access to a licensed therapist who shares science-backed tools that will actually change your life. Hi, I'm Amy Morin, psychotherapist, mental strength trainer, and international best-selling author. In each episode, we cover research-back strategies, like how to stop relying on willpower and start creating habits for lasting change. And the five mental strength-building exercises you can do from your couch. I also speak to world-class experts like Dr. Nicole Kane, who shares how to permanently heal anxiety by addressing the root cause.

With over 200 episodes in our catalog, this podcast is for you if you're ready to crush self-doubt, conquer challenges, become stronger than ever with therapist-approved strategies that can change your life. Listen to Mentally Stronger with therapist Amy Morin, wherever you get your podcasts. Welcome to the I Can't Sleep podcast, where I read random articles to pour you to sleep with my soothing voice. I'm your host, Benjamin Boster. Today's episode is from a Wikipedia article titled Sleep. Sleep is a naturally recurring state of mind and body, characterized by altered consciousness,

relatively inhibited sensory activity, reduced muscle activity, and inhibition of nearly all voluntary muscles during rapid eye movement, REM, sleep, and reduced interoperated. interactions with surroundings. It is distinguished from wakefulness by a decreased ability to react to stimuli, but more reactive than coma or disorders of consciousness,

sleep displaying very different and 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, at eye of movement. This mode of sleep has many other aspects, including virtual paralysis of the body. A well-known feature of sleep is the dream, an experience typically recounted in a narrative form, which resembles waking life while in progress, but which usually can later be distinguished as fantasy.

During sleep, most of the body's systems are in anabolic state, helping to restore the immune, nervous, skeletal, and muscular systems. These are vital processes that maintain mood, memory, and cognitive function, and play a large role in the function of the endocrine and immune systems. The internal circadian clock promotes sleep daily at night. The reverse purposes and mechanisms of sleep are the subject of substantial ongoing research. sleep is a highly conserved behavior across animal evolution. Humans may suffer from various sleep disorders, including dysomnias,

such as insomnia, hypersomnia, narcolepsy, and sleep apnea, parasomnias such as sleepwalking and REM behavior disorder, bruxism, and circadian rhythm sleep disorders. The advent of artificial light has substantially altered sleep time, in industrialized countries. The most pronounced physiological changes in sleep occur in the brain. The brain uses significantly less energy during sleep than it does when awake, especially during non-REM sleep.

In areas with reduced activity, the brain restores its supply of adenosine triphosphate, ETP, the molecule used for short-term storage and transport of energy. In quiet waking, the brain is responsible for 20% of the body's energy use. Thus, this reduction has a noticeable effect on overall energy consumption. Sleep increases the sensory threshold. In other words, sleeping persons perceive fewer stimuli, but can generally still respond to loud noises and other salient sensory events. During slow-wave sleep, humans secret.

burst of growth hormone. All sleep, even during the day, is associated with secretion of prolactin. Key physiological methods for monitoring and measuring changes during sleep, including electroencephalography, EEG of brain waves, electro-oculography, EOG of eye movements, and electromyography, EMG of skeletal muscle activity. Simultaneous collection of these measurements is called polysymnography and can be performed in a specialized sleep laboratory. Sleep researchers also use simplified electrocardiography, EKG, for cardiac activity and actigraphy for motor movements. Sleep is divided into two broad types, non-rapid eye movement, non-REM or N-REM, sleep, and rapid eye movement REM sleep.

Non-REM and REM sleep are so different that physiologists identify them as distinct behavioral states. Non-REM sleep occurs first and after a transitional period is called slow-wave sleep or deep sleep. During this phase, body temperature and heart rate fall, and the brain uses less energy. REM sleep, also known as paradoxical sleep, represents a smaller portion of total sleep time. It is the main occasion for dreams or nightmares and is associated with the desynchronized and fast brain waves, eye movements, loss of muscle tone, and suspension of homeostasis. The sleep cycle of alternate N-REM and REM sleep takes an average of 90 minutes, occurring four to six times in a good night's sleep. The American Academy of Sleep Medicine, AASM, divides NREM into three

stages, N1, N2, and N3, the last of which is also called Delta Sleep or Slow Wave Sleep. The whole period normally proceeds in the order N1, N2, N3, N2, REM. REM sleep occurs as a person returns to stage two or one from a deep sleep. There is a greater amount of deep sleep, stage in three, earlier in the night, while the proportion of REM sleep increases in the two cycles just before natural awakening. Awakening can mean the end of sleep or simply a moment to survey the environment and readjust body position before falling back asleep. sleepers typically awaken soon after the end of a REM phase or sometimes in the middle of REM.

Internal circadian indicators, also with successful reduction of homeostatic sleep need, typically bring about awakening and the end of the sleep cycle. Awakening involves heightened electrical activation in the brain, beginning with the thalamus and spreading throughout the cortex. During a night's sleep, a small amount of time is usually spent in a waking state. As measured by electroencephalography, young females are awake for 0 to 1% of the larger sleeping period. Young males are awake for 0 to 2%. In adults, wakefulness increases, especially in later cycles.

One study found 3% awake time in the first 90-minute sleep cycle, 8% in the second. 10% in the third, 12% in the 4th, and 13 to 14% in the 5th. Most of this awake time occurred shortly after REM sleep. Today, many humans wake up with an alarm clock. However, people can also reliably wake themselves up at a specific time with no need for an alarm. Many sleep quite differently on work days versus days off, a pattern which can lead to chronic circadian desynchronization. Many people regularly look at television and other screens before going to bed,

a factor which may exacerbate disruption of the circadian cycle. Scientific studies on sleep have shown that sleep stage at awakening is an important factor in amplifying sleep inertia. Sleep timing is controlled by the circadian clock, sleep wake, homeostasis, and to some extent by innerity. individual will. Sleep timing depends greatly on hormonal signals from the circadian clock, or Process C, a complex neurochemical system which uses signals from an organism's environment to recreate an internal day-night rhythm. Process C counteracts the homeostatic drive for sleep

during the day in diurnal animals and augments it at night. The super-chiosmatic nucleus, SCN, a brain area directly above the optic chasm, is presently considered the most important nexus for this process. However, secondary clock systems have been found throughout the body. An organism whose circadian clock exhibits a regular rhythm corresponding to outside signals is said to be entrained. An entrained rhythm persists even if the outside signals suddenly disappear. If an entrained human is isolated in a bunker with constant light or darkness, he or she will continue to experience rhythmic increases and decreases of body temperature and melatonin, on a period which slightly exceeds 24 hours.

Scientists refer to such conditions as free-running of the circadian rhythm. Under natural conditions, light signals regularly adjust this period downward, so that it corresponds better with the exact 24 hours of an Earth day. The circadian clock exerts constant influence on the body, affecting sinusoidal oscillation of body temperature between roughly 36.2 degrees Celsius and 37.2 degrees Celsius. The superhyasmatic nucleus itself shows conspicuous oscillation activity, which intensifies during subjective day,

i.e. the part of the rhythm at corresponding with daytime, whether accurately or not, and drops to almost nothing during subjective night. The circadian pacemaker and the supra-chaismatic nucleus has a direct neural connection

to the pineal gland, which releases the hormone melatonin at night. Cortisol levels typically rise throughout the night, peak in the awakening hours, and diminish during the day. Circadian prolactivity and lactant secretion begins in the late afternoon, especially in women, and is subsequently augmented

by sleep-induced secretion to peak in the middle of the night. Cercadian rhythm exerts some influence on the nighttime secretion of growth hormone. The circadian rhythm influences the ideal timing of a restorative sleep episode. Sleepiness increases during the night. Rem's sleep occurs more during body temperature minimum within the circadian cycle. REM sleep occurs more during body temperature minimum within the circadian cycle, whereas slow-wave sleep can occur more independently of circadian time. The internal circadian clock is profoundly influenced by changes in light, since these are its main clues about what time it is.

Exposure to even small amounts of light during the night can suppress melatonin, and secretion and increased body temperature and wakefulness. Short pulses of light at the right moment in the circadian cycle can significantly reset the internal clock. Blue light in particular exerts the strongest effect, leading to concerns that electronic media use before bed may interfere with sleep. Modern humans often find themselves desynchronized from their internal circadian clock, due to the requirements of work, especially night shifts, long-distance travel, and the influence of universal indoor lighting. Even if they have sleep dead or feel sleepy, people can have difficulty staying asleep at the peak of their circadian cycle. Conversely,

they can have difficulty waking up in the trough of the cycle. A healthy young adult and trained to the sun will, during most of the year, fall asleep a few hours after sunset. experience body temperature minimum at 6 a.m. and wake up a few hours after sunrise. Generally speaking, the longer an organism is awake, the more it feels a need to sleep. Sleep debt. This driver of sleep is referred to as process S. The balance between sleeping and waking is regulated by a process called homeostasis. Induced or perceived lack of sleep is called sleep deprivation. Process S is driven by the depletion of glycogen and accumulation of adenosine in the forebrain that disinhibits the ventralateral pre-optic nucleus, allowing for inhibition of the ascending reticular activating system.

Sleep deprivation tends to cause slower brain waves in the frontal cortex, shortened attention span, higher anxiety, impaired memory, and a grouchy mood. Conversely, a well-rested organism tends to have improved memory and mood. Neurophysiological and functional imaging studies have demonstrated that frontal regions of the brain are particularly responsive to homeostatic sleep pressure. There is disagreement on how much sleep debt it is possible to accumulate, and whether sleep debt is accumulated against an individual's average sleep or some other benchmark. It is also unclear whether the prevalence of sleep debt among adults has changed appreciably in the industrialized world in recent decades.

Sleep debt does show some evidence of being cumulative. Subjectively, however, humans seem to reach maximum sleepiness after 30 hours of waking. It is likely that in Western societies, children are sleeping less than they previously have. One neurochemical indicator of sleep dead is adenosine, a neurotransmitter that inhibits many of the bodily processes associated with wakefulness. Adenosine levels increase in the cortex and basal forebrain during prolonged wakefulness and decrease during the sleep recovery period, potentially acting as a homeostatic regulator of sleep. Coffee and caffeine temporarily block the effect of adenosine, prolong sleep latency, and reduce total sleep time and quality.

Humans are also influenced by aspect of social time, such as the hours when other people are awake, the hours when work is required, the time on the clock, etc. Time zones, standard times used to unify the timing for people in the same area, correspond only approximately to the natural rising and setting of the sun. The approximate nature of the time zone can be shown with China, a country which used to span five time zones and now officially uses only one.

In polyphysic sleep, an organism sleeps several times in a 24-hour cycle, whereas in monophysic sleep occurs all at once. Under experimental conditions, humans tend to alternate, more frequently between sleep and wakefulness, i.e. exhibit more polyphysic sleep, if they have nothing better to do. Given a 14-hour period of darkness in experimental conditions, humans tended towards bimodal sleep with two sleep periods concentrated at the beginning and at the end of the dark time. Bimodal sleep in humans was more common before the Industrial Revolution. Different characteristic sleep patterns such as the familiarly so-called early bird and night owl are called

chronotypes. Genetics and sex have some influence on chronotype, but so do habits. Chronotype is also liable to change over the course of a person's lifetime. Seven-year-olds are better disposed to wake up early in the morning than are 15-year-olds. Chronotypes far outside the normal range are called circadian rhythm sleep disorders. The siesta habit has recently been associated with a 37% lower coronary mortality, possibly due to reduced cardiovascular stress mediated by daytime sleep. Short naps at midday and mild evening exercise were found to be effective for improved sleep, cognitive tasks, and mental health in elderly people. Many people experience a temporary drop and alertness in the early afternoon, commonly known as the post-lunch dip.

While a large meal can make a person feel sleepy, the post-lunch dip is mostly an effect of the circadian clock. People naturally feel most sleepy at two times of the day about 12 hours apart. For example, at 2 a.m. and 2 p.m. At those two times, the body clock is activated. At about 2 p.m., it overrides the homeostatic build-up of sleep debt, allowing several more hours of wakefulness. At about 2 a.m., with the daily sleep debt paid off, it is activated again to ensure a few more hours of sleep. It is hypothesized that a considerable amount of sleep-related behavior, such as when and how long a person needs to sleep, is regulated by genetics. Researchers have discovered some evidence that seems to support this assumption.

Monozygotic, identical, but not dysagogic fraternal twins, tend to have similar sleep habits. Neurotransmitters, molecules whose production can be traced to specific genes, are one genetic influence on sleep which can be analyzed. The circadian clock has its own set of genes. genes which may influence sleep include A, B, C9, DEC2, and variance near Pax 8 and VRK2. The quality of sleep may be evaluated from an objective and a subjective point of view. Objective sleep quality refers to how difficult it is for a person to fall asleep and remain in a sleeping state, and how many times they wake up during the single night. Poor sleep quality disrupts the cycle of transition between the different stages of sleep.

Subjective sleep quality in turn refers to a sense of being rested and regenerated after awaking from sleep. A. Harvey at all 2002 found that insomniacs were more demanding in their evaluations of sleep quality than individuals who had no sleep problems. Homeostatic sleep propensity, the need for sleep as a function of the amount of time elapsed since the last adequate sleep episode, must be balanced against the circadian element for satisfactory sleep. Along with corresponding messages from the circadian clock, this tells the body it needs to sleep. A person who regularly awakens that an early hour will generally not be able to sleep much

later than is or her normal waking time, even if moderately sleep deprived. The timing is correct when the following two circadian markers occur after the middle of the sleep episode and before awakening, maximum concentration of the hormone melatonin, and minimum core body temperature. Human sleep needs vary by age and amongst individuals. Sleep is considered to be adequate when there is no daytime sleepiness or dysfunction. Moreover, self-reported sleep duration is only moderately correlated with actual sleep time as measured by octagraphy, and those affected with sleep state misperception may typically report having slept only four hours despite having slept a full eight hours. Researchers have found that sleeping six to seven hours each night correlates with longevity and cardiac health and humans,

though many underlying factors may be involved in the causality behind this relationship. sleep difficulties are furthermore associated with psychiatric disorders such as depression, alcoholism, and bipolar disorder. Up to 90% of adults with depression are found to have sleep difficulties. Disregulation detected by EEG includes disturbances in sleep continuity, decreased delta sleep, and altered REM patterns with regard to latency, distribution across the night and density of eye movements. By the time infants reach the age of two,

their brain size has reached 90% of an adult-sized brain. A majority of this brain growth has occurred during the period of life with the highest rate of sleep. The hours that children spend asleep influence their ability to perform on cognitive tasks. Children who sleep through the night and have few night-waking episodes, have higher cognitive attainments

and easier temperaments than other children. Sleep also influences language development. To test this, researchers taught infants a faux language and observed their recollection of the rules for that language. Infants who slept within four hours of learning the language could remember the language rules better, while infants who stayed awake longer,

did not recall those rules as well. There is also a relationship between infants' vocabulary and sleeping. Infants who sleep longer at night at 12 months have better vocabularies at 26 months. Children need many hours of sleep per day in order to develop and function properly, up to 18 hours for newborn babies, with a declining rate as a child ages. Early in 2015, after a two-year study, the National Sleep Foundation in the U.S. announced newly revised recommendations as shown in the table below. Newborns, zero to three months, 14 to 17 hours. Infants, 4 to 11 months, 12 to 15 hours.

Toddlers, 1 to 2 years, 11 to 14 hours. Preschoolers, 3 to 4 years, 10 to 13 hours. School-age children, 5 to 12 years, 9 to 11 hours. Teenagers, 13 to 17 years, 8 to 10 hours. Adults, 18 to 64 years, 7 to 9 hours. Older adults, 65 years and over, 7 to 8 hours. The human organism physically restores itself during sleep, healing itself and removing metabolic wastes which build up during periods of activity.

This restoration takes place mostly during slow wave sleep, during which body temperature, heart rate, and brain oxygen consumption decrease. The brain especially requires sleep for restoration, whereas in the rest of the body, these processes can take place during quiescent waking. In both cases, the reduced rate of metabolism, metabolism enables countervailing restorative processes. While awake, metabolism generates reactive oxygen species, which are damaging to cells. During sleep, metabolic rates decrease, and reactive oxygen species generation is reduced,

allowing restorative processes to take over. The sleeping brain has been shown to remove metabolic waste products at a faster rate than during an awake state. It is further theorized that sleep helps facilitate the synthesis of molecules that help repair and protect the brain from these harmful elements generated during waking. Anabolic hormones such as growth hormones are secreted preferentially during sleep. The concentration of the sugar compound glycogen in the brain increases during sleep and is depleted through metabolism during wakefulness. studies suggest that sleep deprivation may impair the body's ability to heal wounds. It has been shown that sleep deprivation affects the immune system. It is now possible to state that sleep loss impairs human function and immune challenge alters sleep.

And it has been suggested that sleep increases white blood cell counts. A 2014 study found that depriving mice of sleep increased cancer griefs, and dampen the immune system's ability to control cancers. The effect of sleep duration on somatic growth is not completely known. One study recorded growth, height, and weight as correlated to parent-reported time in bed and 305 children over a period of nine years, age 1 to 10. It was found that the variation of sleep duration among children does not seem to have an effect on growth, It is well established that slow-wave sleep affects growth hormone levels in adult men.

During eight-hour sleep, Van Koder, LaPro, and Platt found that the men with a high percentage of slow-wave sleep, SWS, average 24%, also had high-growth hormone secretion, while subjects was a low percentage of SWS, average 9%, had low-growth hormone secretion. It has been widely accepted that sleep must support the formation of long-term memory and generally increasing previous learning and experiences recalls. However, its benefit seems to depend on the phase of sleep and the type of memory. For example, declarative and procedural memory recall tasks applied over early and late nocturnal sleep, as well as wakefulness-controlled conditions,

have been shown that declarative memory improves more during early sleep, dominated by SWS, while procedural memory during late sleep, dominated by REM sleep. Regarding to declarative memory, the functional role of SWS has been associated with the hippocampal replays of previously encoded neural patterns that seem to facilitate long-term memories consolidation. This assumption is based on the active system consolidation hypothesis, which states that repeated reactivations of newly encoded information

in hippocampus during slow oscillations in NREM sleep mediate the stabilization and gradually integration of declarative memory with pre-existing knowledge networks on the cortical level. It assumes the hippocampus might hold information only temporarily and in fast learning rate whereas the neocortex is related to long-term storage and slow learning rate. This dialogue between hippocampus and neocortex occurs in parallel, with hippocampal sharp wave ripples and thalamal cortical spindles, synchrony that drives the formation of spindle ripple event, which seems to be a prerequisite for the formation of long-term memories.

During sleep, especially REM sleep, people tend to have dreams. elusive first-person experiences which seem realistic while in progress, despite their frequent bizarre qualities. Dreams can seamlessly incorporate elements within a person's mind that would not normally go together. It can include apparent sensations of all types, especially vision and movement.