The Possible Functions of REM Sleep and Dreaming - Neuroscience - NCBI Bookshelf
Rapid eye movement sleep (REM) has since its discovery been closely Another possible relationship between the two phenomena. Oct 27, Research finds that REM sleep and dreams are linked to health benefits, like a lower stress Why Dreaming May Be Important for Your Health. Adding to the uncertainty about the purposes of REM sleep and dreaming is the REM sleep and dreams are involved in the transfer of memories between the.
Muscle inhibition may result from unavailability of monoamine neurotransmitters restraining the abundance of acetylcholine in the brainstem and perhaps from mechanisms used in waking muscle inhibition.
The Importance of REM Sleep & Dreaming
Certain scientific efforts to assess the uniquely bizarre nature of dreams experienced while asleep were forced to conclude that waking thought could be just as bizarre, especially in conditions of sensory deprivation.
The prospect that well-known neurological aspects of REM do not themselves cause dreaming suggests the need to re-examine the neurobiology of dreaming per se.
People awakened from REM have performed better on tasks like anagrams and creative problem solving. REM sleep through this process adds creativity by allowing "neocortical structures to reorganise associative hierarchies, in which information from the hippocampus would be reinterpreted in relation to previous semantic representations or nodes.
In the ultradian sleep cycle an organism alternates between deep sleep slow, large, synchronized brain waves and paradoxical sleep faster, desynchronized waves. Sleep happens in the context of the larger circadian rhythmwhich influences sleepiness and physiological factors based on timekeepers within the body.
Sleep can be distributed throughout the day or clustered during one part of the rhythm: Many animals and some people tend to wake, or experience a period of very light sleep, for a short time immediately after a bout of REM.
The relative amount of REM sleep varies considerably with age. The first REM episode occurs about 70 minutes after falling asleep. Cycles of about 90 minutes each follow, with each cycle including a larger proportion of REM sleep.
In faster-developing mammals this process occurs in utero. The proportion of REM sleep then decreases significantly in childhood. Older people tend to sleep less overall but sleep in REM for about the same absolute time, and therefore spend a greater proportion of sleep in REM. Processing of external stimuli is heavily inhibited during phasic REM, and recent evidence suggests that sleepers are more difficult to arouse from phasic REM than in slow-wave sleep.
On recovery nights, an individual will usually move to stage 3 and REM sleep more quickly and experience an REM reboundwhich refers to an increase in the time spent in REM stage over normal levels. These findings are consistent with the idea that REM sleep is biologically necessary.
There are also positive consequences of REM deprivation.REM Sleep: What It Is And Why It's Great For Dreaming!
Some symptoms of depression are found to be suppressed by REM deprivation; aggression may increase, and eating behavior may get disrupted. Several reports have indicated that REM deprivation increases aggression and sexual behavior in laboratory test animals.
Rapid eye movement sleep - Wikipedia
Mean body temperature falls continually during this period. Although sleep deprivation in general annoys most of the population, it has repeatedly been shown to alleviate depression, albeit temporarily.
Thus, researchers have devised methods such as altering the sleep schedule for a span of days following a REM deprivation period  and combining sleep-schedule alterations with pharmacotherapy  to prolong this effect.
Whereas most sleep researchers accept the idea that the purpose of non-REM sleep is at least in part restorative, the function of REM sleep remains a matter of considerable controversy. A possible clue about the purposes of REM sleep is the prevalence of dreams during these epochs of the sleep cycle.
The occurrence of dreams can be tested by waking volunteers during either non-REM or REM sleep and asking them if they were dreaming.
Rapid eye movement sleep
Subjects awakened from REM sleep recall elaborate, vivid, hallucinogenic and emotional dreams, whereas subjects awakened during non-REM sleep report fewer dreams, which, when they occur, are more conceptual, less vivid and less emotion-laden. Dreams have been studied in a variety of ways, perhaps most notably within the psychoanalytic framework of revealing unconscious thought processes considered to be at the root of neuroses. Sigmund Freud's The Interpretation of Dreams, published inspeaks eloquently to the complex relationship between conscious and unconscious mentation.
It is by no means agreed upon, however, that dreams have the deep significance that Freud and others have given them, and the psychoanalytic interpretation of dreams has recently fallen into disfavor. Nevertheless, most people probably give some credence to the significance of dream content, at least privately. Adding to the uncertainty about the purposes of REM sleep and dreaming is the fact that deprivation of REM sleep in humans for as much as two weeks has little or no obvious effect on behavior.
Such studies have been done by waking volunteers whenever their EEG recordings showed the characteristic signs of REM sleep. Although the subjects in these experiments compensate for the lack of REM sleep by having more of it after the period of deprivation has ended, they suffer no obvious adverse effects. Similarly, patients taking certain antidepressants MAO inhibitors have little or no REM sleep, yet show no obvious ill effects, even after months or years of treatment.