For most of us, one-third of our lives is spent sleeping and many of us would rather have longer waking time to do the things we want or need to do. But sleep is required if we are going to be healthy and alert and do the things we need or want to do.
Sleeping rejuvenates the brain, sort of like a battery recharging, and indeed, the brain discharges electrical impulses required to operate organs, brain functions, et cetera.
Even just resting helps the mind and body.
In creatures that have developed brains, they experience electrical rhythms that differ from the wake state. Deprivation of sleep
will dull the senses and thinking process, as well as cause a low energy level for required body functions. Lack of sleep over long extended periods will even cause one to hear voices and possibly illusions. Those who have military combat experience can relate to this phenomenon.
Humans and other forms of animals have a “biological clock
” that makes us sleepy in certain periods of a 24-hour cycle. Sleep schedules can be modified, as the person who works the “skeleton shift” can readily tell you. But unless you are a nocturnal creature, generally one becomes sleepy in the darkness hours of the 24-hour period. Strenuous activities or long wake periods also makes one sleepy. Monotony, sitting in front of a warm fire, restricted movement, and illness can make a person sleepy.
Science has shown us that the amount of sleep required for each species is proportional to the amount of restoration required. Cats, for example, will take a series of naps and are generally nocturnal. In humans there is a wide variation in sleep required, some being content and healthy with only three or four hours per 24-hour period. A few may require as much as ten hours of sleep in order to feel rested.
Infants sleep a lot because they are still in a development stage of growth and their organs are still developing as when in the womb. Adults find that their sleep pattern becomes more broken. Military personnel, especially those in combat arms occupations, learn that “cat naps” are beneficial when a full night sleep is not possible. It’s enough to keep them going for a period of time, but eventually signs of sleep depredation begins to set in and it is time for some “R&R”.
Generally those who require longer sleep periods have shorter reaction times and body temperatures by day
There are two levels of sleep: REM
– rapid eye movement – and NREM
– nonrapid eye movement. These two levels will alternate through a night’s sleep.
NREM begins as a light dozing period and steadily progresses more deeply as muscles relax, heart rate and respiration slow down, and body temperature decreases.
REM sleep begins about 90 minutes after NREM and this is what people call “deep sleep”.
When one dreams, the heart and respiration rate increases, as well as brain activity, which is measured by EEG
. Your muscles sort of become paralyzed by your brain when sleeping, in most cases, to prevent one from acting out what is taking place in your dream.
While dreaming, your mind is active at a different level and can occur in either REM or NREM state – or both. Talking may occur in either REM or NREM state of sleeping. Some experience “sleep walking” and that sort of dreaming is not remembered when awakening.
The sleep period is also a time for the body to rejuvenate, as previously mentioned. Protein biosynthesis
occurs and skin is restored with new skin cells, more rapidly than other periods of the 24-hour period.
In higher animals, hormones
reinforce cellular processes. Sleep is proportional to body weight and key to a good night’s sleep is regulated physical exercise, a quality mattress, a warm, but well-ventilated room, a malted milk drink, and sexual satisfaction – all promote good sleep. Sleep does not equal laziness, meaning some require more than others and is part of the natural process of keeping fit. Obviously, a person who is injured or ill requires more rest than when healthy.
Humans have contemplated the phenomenon of dreaming since before recorded history, viewing it in different ways and different views in different cultures. Some believe when one dreams it is an out-of-body experience
and others believe it is an adventure into an altered state or spirit world; where one can make contact with angels and/or the deceased. At times, dreams have been looked upon as prophecies
, especially when the same dream reoccurs over consecutive sleep periods. But most recently, dreams have been tied into creativity and imagination.
Reported in 2009 by UCLA and University of California researchers in San Diego, sleep may be sparking creative thoughts that will enable us to do wonderful things when awake.
A study of this sort was also conducted by investigators at the University of Lübeck in Germany in 2004 that revealed the same phenomenon. It was found that subjects who were given adequate rest periods could solve difficult math problems at a rate of 59%. They found the solution while they were sleeping, after thinking of it before sleeping.
Technically, your brain is something like a computer hard drive that never really shuts down totally, just different levels.
When you are conscious there are sights, sounds and other distractions; but when you are asleep there is more focus in certain parts of your brain; and all the while recharging other portions. This has been called for for a long time, the state of unconscious thought.
Interestingly, while systems in your brain are shutting down; others, more focused, are engaging like vision centers creating scenes in your head like a Hollywood film. Imagination engages. Mary Shelley got her idea of Frankenstein from a dream about a man being assembled from graveyard body parts in 1816.
Traditionally it has been thought that the left hemisphere of the brain is the rational and mathematical region and the right hemisphere is the creative side. But scientists are discovering, like Liza Aziz Zadeh, University of Southern California, that it is not that simple. She wrote:
The specific regions that are active during the creative process largely depend on the kind of task the person engaged in.
At the University of Rome, in 2008, something similar was discovered. In NREM sleep, the left and right hemisphere passes information similar to when awake, but more controlled and restrained.
Too often we cannot remember our dreams, just fuzzy bits. The best strategy to not lose dream thought is keep a journal by your bed, as well as abstain from alcohol and caffeine before sleeping. It is suggested that engaging in pre-sleep priming thought, contemplating the problem you would like to solve, will increase the chance of finding the solution while sleeping. This might not always occur, but the odds are in your favor.
You may not consider yourself creative in the waking hours, but your sleeping brain will sometimes prove differently. In your dreams, you can be or do anything you want.
Kramer, M.; Bridge of Dreaming; London, 1989.