As per ved, in the science of
creation out of creator brhmah,
sustenance during the life term and during the cycles of birth-death in sansaar
and re-absorption back into creator
brhmah when one's every life cycle ends or when life cycle of
creation ends and also during daily sleep....one's aatmaa
(soul) exists in
various mortal bodies of living beings....
..aatmaa exists in three states in
each mortal living body....awake state called vaishvaanar
in the mortal body itself....then during the time we call sleep....aatmaa
keeps the body alive but migrates to its ling
or shukshma sharir made of 10-indriyo,
manas, buddhi and ahankaar
showing us dreams of past, present and future and calls itself taijas in this
dream state......and then in sushupti or
deep sleep state aatmaa migrates to
rest in the creator of the body which is prakruti
or mahaa-maayaa yet keeping the body
alive and calls itself prgnaa.....
..in coming days PVAF will present more on the states of an aatmaa
during its continual travels in this creation in the science
of aaatmaa called aadhyaatmaa which is now posted on
this web site AASHRAM NEWS board every day
for the last 15 days.....
...the current science knows very little about why we need sleep or why we
sleep....compare the above with what the current science knows by clicking on
the next line and also visiting by clicking on the highlite SLEEP
AND DREAMS AT HEALTH.DISCOVERY.COM for lots of current
science on sleep and dream....
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What
Happens When We Sleep?
from
SLEEP
AND DREAMS AT HEALTH.DISCOVERY.COM
While many of us think of sleep as a largely forgotten stretch of time when
nothing happens, sleep is, neurologically speaking at least, a busy time indeed.
Although sleep's importance is inarguable, scientists do not know exactly why it
is so important to our survival. What happens when we sleep?
Sleep Stages
Scientists recognize sleep stages by tracking the changes in brain waves. The
five sleep stages are repeated as many as five times during the night. As the
night progresses, each cycle lengthens, and REM sleep, during which most
dreaming takes place, extends.
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Stage 1
In this brief stage, which may last only a few minutes, the body drifts to
sleep. Brain waves are mostly high amplitude, slow waves and occasional
alpha waves (like those found when awake).
Percent of total sleep time for young adults: 5 percent.
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Stage 2
Heartbeat and breathing slow and the sleep is deeper than in Stage 1.
Slow-wave sleep continues with peaks of brain waves (known as sleep
spindles) occurring.
Percent of total sleep time for young adults: 44 to 55 percent.
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Stages 3 and 4
These are the stages of deepest sleep, when brain waves are slowest. During
these stages breathing and heartbeat slow further and muscles relax. Dreams
are more common than in the earlier stages and sleepwalking and talking may
occur during Stages 3 and 4.
Percent of total sleep time for young adults: 15 to 23 percent.
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REM
Rapid eye movement (REM) sleep stages lengthen through the night. The first
REM cycle may be only 10 minutes while the last could last as long as an
hour. During this cycle the heartbeat increases, breathing becomes shallow,
eyes move rapidly, muscles are relaxed, and dreams are most vivid. Brain
waves resemble those during waking.
Percent of total sleep time for young adults: 20 to 25 percent.
Why Do We Sleep?
Sleep is essential to life. Laboratory animals deprived of sleep die. And humans
don't seem to be immune to the life-threatening effects of sleeplessness. A
survey conducted by the American Cancer Society concluded that people who sleep
6 hours or less per night, or who sleep 9 hours or more, had a death rate 30
percent higher than those who regularly slept 7 to 8 hours. Even those who slept
6 hours or less who otherwise had no health problems had death rates 1.8 times
higher than those who slept "normal" hours.
But what is the purpose of sleep? Despite the obvious nature of that
question, scientists do not really agree on why we sleep. There are several
theories:
- Adaptive Theory
This theory holds that sleep improves an animal's likelihood of survival.
Those with sleeping habits appropriate to their environment are most likely
to survive. Nocturnal species have very different sleep habits than diurnal
hunters, for example, making them more likely to flourish.
- Energy Conservation Theory
Fast-moving animals with high metabolisms sleep more than those that burn
calories more slowly, thereby conserving their energy for sprints.
- Restorative Theory
According to this theory, the body restores itself during sleep. Researchers
know that neurotoxins are neutralized during sleep, and have reported that
cells divide, tissue synthesizes and growth hormones are released during
slow-wave (or non-REM) sleep. Athletes, for example, spend more time in
slow-wave sleep (Stages 3 and 4) than others, and children and young people
spend a larger portion of their sleep in slow-wave sleep than older people.
- Programming-Reprogramming Theory
This theory holds that unimportant information is "erased" and
important information is locked into more permanent memory. Infants, who are
acquiring information at a rate faster than at any other point during life,
sleep most. All sleep may not be equal for reinforcing learning, however.
Recent research indicates that REM sleep may be the key. Babies and children
experience a larger portion of REM sleep than adults, and adults who are in
school or undergoing intense intellectual training increase their amount of
REM sleep. When people are deprived of REM sleep they are less adept at
creative problem solving.
Circadian Rhythms
Our biological "clock" largely corresponds to the cycle of the day,
and in fact the term "circadian" means "about a day." The
cycle of wakefulness and sleep is tied closely to core body temperature: the
higher the temperature, the more alert we are; conversely, when it reaches its
low point, sleepiness may be irresistible. The body's rhythms seem based on two
sleep periods each day: a long one through the night and a second short period
in the afternoon, when many people nap or at least feel less alert than at other
points during the day.
Researchers have found that when people are removed from any outside
reminders of time (no clocks, no outside light, etc.) their "clock"
seems to be set approximately for a 25-hour day. When one's personal biological
clock gets out of sync with society's clock, sleep problems can ensue. For more
information on circadian sleep disorders, see "Sleep
Disorders".
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