This is Part 4, in an on-going study of dreams. Part 3 ended with the start of discussing the four different stages. In this Part, we'll look deeper into these four stages and also how our brain processes stimuli produced from our dreams and how our body keeps from actually acting out our dreams.
REM sleep is also known as 'paradoxical sleep', because during it brain activity, adrenaline levels, pulse rate and oxygen consumption come closer to those in wakefulness, yet muscle tone relaxes and the sleeper may prove particularly difficult to arouse. It is during the REM sleep that more dreaming takes place. It seems that physiological differences between REM sleep and the other three, deeper levels of sleep are as great as those between waking and sleeping.
A number of American dream researchers have even suggested that REM sleep warrants recognition as a third basic form of human existence, seeming to confirm the ancient Hindu tradition that consciousness consists of three distinct levels: waking, dreamless sleep and dreaming.
In the 1960's researchers found that REM deprivation appears to lead to daytime irritability, fatigue, memory loss and poor concentration.
Volunteers who were systematically deprived of REM sleep by being aroused whenever they entered the eye activity phase caught up on subsequent nights by engaging in more REM sleep than usual. If a subject is faced with total sleep deprivation, because of illness or other factors, the REM state has even been known to force its way into waking consciousness. It seems that we may badly need REM sleep, and this could be associated with a psychological need to dream.
Emotions are engaged during REM, causing heart rate and breathing to become erratic at times. Gastric acid production may increase by as much as ten times, asthmatics are more prone to attacks, and there is an increased tendency to cardiac arrest. Intriguingly, however, these extreme physiological changes do not necessarily have a direct relationship with reported dream content, but may instead result from what appears to be a total arousal of parts of the nervous system. Yet however, real such sensory experiences appear to the brain, something prevents us from performing in full actions and emotions that fill our dreams. There is a general loss of muscle tone during REM sleep and the eye muscles appear to be the only ones that are physically involved in acting out dream events. It has been shown that when dreams are most vivid, certain inhibitors are produced to prevent muscles from receiving the relevant impulses from the brain, thus ensuring that we do not act on sensory stimuli experienced in the dream. It is perhaps this effective paralysis that gives rise to the dream sensations of being unable to run, of attempting in vain to scream, or of trying to walk, but being stuck in sand or water. The brain somehow prevents us from moving physically when asleep with the power and agility possessed by the dreaming mind.
Join me for Part 5- where we'll continue to study together how dreaming effects our waking life. Information from: "The Secret Language of Dreams"; By David Fontana.
http://www.bonanzle.com/inspired
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