Why Do We Sleep?

This first draft of an idea of why we sleep, is one of the many hypotheses out there. I think it is the right one, and here offer support for it
This is a very rough first draft of an idea of why we sleep.

NREM Facts
REM Facts

NREM is for Body Repair, physical repair,
REM – is for Mind repair and to lessen psychological stress
Deep sleep for body repair, REM sleep for mind repair
Test: If this hypothesis is correct,
Sleep after a day of high mental stress should have more REM sleep.
Sleep after a day of high physical stress should have more deep sleep or NREM
Through the night the NREM periods decrease in length and the REM increase. About 80% of sleep time is in NREM with 20% in REM
NREM periods are longer with more time in early sleep.
REM periods are shorter with more time in later sleep
NREM is for body repair. The body is active, the mind is resting
NREM is the time to repair the body:

finish digestion
make hormones for next day’s digestion. Growth and sex hormones,
take water from the colon for next day’s digestion
fight infection in colon where 75% of the body’s immune system is.

Fact: After bacterial or fungal infection more NREM sleep
Fact: Spike a fever in NREM to fight infection, but not in REM
Fact: In NREM sleep temperature is regulated. The body can shiver to warm up, or sweat to cool down.
Fact: Sleep Walking, body moving, is in NREM
Fact: Colon contractions are small
Fact: Thermal regulation in NREM
Fact: NREM sleep came millions of years before REM (body before mind?)
Fact: Left brain hemisphere becomes more active during NREM. Only NREM sleep exists unihemispherically,
Fact: Children and Adolescents have longer periods in NREM sleep. (Body growing?)
Fact: NREM sleep has been associated with several physiological phenomena, including glucose metabolism, sympathetic nervous system activity, hormonal secretion and blood pressure regulation.
Fact: The current study shows that deep sleep is the key to jump-starting puberty,
Fact: Cortisol, the stress hormone, seems to be released in NREM sleep. More cortisol = more NREM sleep. Acute administration of cortisol increases non-rapid-eye movement (NREM) sleep, suppresses rapid-eye movement (REM) sleep
Fact: The interval between peristaltic contractions in the small intestine and colon is increased in NREM sleep compared to wakefulness and there is an increase in colonic activity after waking.
Fact: NREM sleep is a much deeper phase of sleep than REM sleep, and during this phase, the pituitary produces high levels of HGH.
Fact: In NREM sleep your muscles are more relaxed than when you are awake but you are able to move (although you do not because the brain is not sending signals to the muscles to move).
Fact: Bedwetting is a common sleep problem in children ages 6–12, occurring only during NREM sleep.
Fact: Night terrors occur in NREM sleep, are most common in boys ages 5 – 7 and are fairly common in children ages 3 – 7…
Fact: Sleepwalking most often occurs during deep non-REM sleep
Fact: The release of growth hormone reaches its peak during NREM, deep sleep.


REM is for mind repair. The mind is active, the body is resting

REM is the time to repair the mind:

sets memories
consolidates and processes information
builds up on neurotransmitters, like serotonin and dopamine

Fact: Brain activity increases in motor and sensory areas
Fact: REM sleep is triggered by neurons in the pons.
Fact: Brain temperature is slightly higher in REM, though less than during waking.
Fact: The parts of the brain active during REM, include almost all but Cerebrum
Fact: Heart rate and blood pressure increase
Fact: Blood flow to brain 50-200% greater than NREM.
Fact: More psychological depression leads to more REM sleep.
Fact: Studies of the sleep patterns of people under psychological stress, show that they have more REM sleep, whereas studies of the sleep patterns of people under more physical stress, show they have more NREM sleep.
Fact: Mind is more active with dreams.
Fact: Rapid Eye Movement during REM sleep.
[Perhaps to moisten the eyes and get the sleep waste out. Ear change is similar ]
Fact: Muscles are paralyzed in muscle atonia; except the heart, diaphragm, eye muscles, middle ear, and smooth muscles such as those of the intestines and blood vessels. The paralysis of muscles in the arms and legs and under the chin in REM show no electrical activity.
Fact: Less breathing regulation. Breathing increases, varies, and is more shallow.
Fact: Colon contractions are greater.
Fact: No thermal regulation, sweating or shivering. Shift to environmental temp.
Fact: Sexual arousal increases
Fact: High amounts of REM during infant development – for brain development?
A newborn baby spends more than 80% of total sleep time in REM.
Fact: Body hits low temperature at about 4-6, when REM is usually active.
Fact: Brain areas for both memory processing (the hippocampus) as well as emotional processing (the amygdala) are active during REM sleep. REM sleep plays a key role in learning and memory. During REM sleep, your brain consolidates and processes the information you’ve learned during the day, forms neural connections that strengthen memory, and replenishes its supply of neurotransmitters, including feel-good chemicals such as serotonin and dopamine that boost your mood during the day.
Fact: Dream sleep and dreaming are associated with high levels of brainstem arousal and right cerebral activity in REM.
Fact: The length and intensity of REM sleep increases with each succeeding cycle. During the first cycle, REM sleep might be only 10 minutes long, while during the last cycle it might stretch to 90 minutes.
Fact: If a person’s REM sleep is disrupted, the next sleep cycle does not follow the normal order, but often goes directly to REM sleep until the previous night’s lost REM time is made up.
Fact: During REM sleep, intense activity is observed in the limbic system, a set of structures heavily involved in emotions. Two of these structures are especially active: the hippocampal regionand, in particular, the amygdala. Once again, it is interesting to note that this intense limbic activity does not occur during the phases of NREM, non-REM sleep , when the dreams that people have are far less emotional.
Fact: REM sleep decreases up to 50% during puberty
Fact: Studies of the sleep patterns of people under psychological stress, show that they have more REM sleep, whereas studies of the sleep patterns of people under more physical stress, show they have more NREM sleep.
Fact: The more severe the depression, the earlier the first REM begins.
Fact: Once evolutionary relationships were factored in, the data showed that animals with big brains for their body size need a significantly higher percentage of REM sleep – supporting a role in intelligence and cognitive function. And species with high metabolic rates for their size needed less non-REM sleep, not more.
Fact: Glucose utilization is greater in REM versus non-REM sleep.
Fact: Research has shown that children with short sleep duration spend proportionally less time in REM sleep.
Fact: Peristaltic movements of the digestive tract decrease (REM)
Fact: Increased fat intake was associated with a lower percentage of REM sleep, a higher arousal index and apnea-hypopnea index, and a lower sleep efficiency.
Fact: It’s been shown that brain areas for both memory processing (the hippocampus) as well as emotional processing (the amygdala) are active during REM sleep. At the same time, our brain has a dramatically different neurochemistry compared with wakefulness or the other stages of sleep: There is a lack of stress neurochemicals, while chemicals important for memory processing are enhanced.
Fact: Nightmares occur in REM.

These posts are built on the premise of the evolution of catabolic and anabolic processes to other separate deconstructive and constructive processes.
Catabolic and anabolic processes evolve but they do not blend


Tags: , ,

One Response to “Why Do We Sleep?”

  1. musea Says:

    Blood Barrier connected to REM sleep?

    This is very interesting:

    I suggested that
    NREM is body repair
    REM is mind repair.

    The blood barrier is in 3 places:
    blood – brain barrier (excluding the circumventrical organs = mostly lower brain)
    blood – ocular barrier
    blood – testes barrier


    NREM, = body repair in the parts of the body without barriers
    REM = repair in the 3 parts of the blood barrier

    Note: REM is dreams in the mind, rapid eye movement, and testosterone production.

    This study seems to support that idea

    “REM sleep restriction increased blood-brain barrier permeability”

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


Get every new post delivered to your Inbox.

Join 127 other followers