Sleep- Learning Objectives
We heal while we sleep, we grow while we sleep, our bodies need sleep to regenerate ourselves. We are healing both our bodies and our minds.
Here are some reasons why you cannot sleep, sleep disorders, circadian system, light entrainment.
How light affects your sleep?
All living beings have a natural relationship with light. We have evolved to live in a bright day and dark night. During the daylight hours our bodies release hormones to keep up awake; melanopsin and and dusk stimulate the release of ones to make us sleepy; melatonin. This connection to light in our Circadian System is called Light Entrainment.
Our circadian System helps us sleep, and when disturbed by exposure to blue white light, we produce a hormone called Serotonin. At night, our bodies are signaled to go to sleep by the production of Melatonin. Blue white light is found naturally during mid-day sunshine; therefore, when we see it at night it wakes us up. It takes up to two hours for us to produce Melatonin and begin or go back to sleep.
Light can prevent or delay sleep depending on the color. Exposure to blue white light when you wake in the night, can keep you awake, use amber or red nightlights. For some night light ideas visit my Pinterest board: https://www.pinterest.com/trishodenthal/beautiful-night-lights/
Fragmented sleep means multiple interruptions during the night.
In order to sleep the body needs to cool down.
Eating before sleep causes temperature to rise as the body sends blood to the core, to digest and absorb nutrients.
Acid reflux is often caused by night time eating.
Alcohol induces dehydration.
Noises, pets, and snoring also effect sleep.
Hypertension & diabetes from insufficient sleep
Myth: Health problems such as obesity, diabetes, hypertension, and depression have no relation to the amount and quality of a person's sleep.
Fact: More and more scientific studies are showing correlations between poor quality sleep and/or insufficient sleep with a variety of diseases. Blood pressure is variable during the sleep cycle. Interrupted sleep, however, can negatively affect the normal variability and may lead to hypertension and cardiovascular problems. Research indicates that insufficient sleep impairs the body's ability to use insulin, which can lead to the onset of diabetes. Fragmented sleep can cause a lowered metabolism and increased levels of the hormone cortisol. Increased cortisol levels can result in an increased appetite and a decrease in one's ability to burn calories. 
What sleep ritual is yours?
As someone who will wake mid sleep, I have employed all of these. The goal is enough tools in your sleepy toolbox to find a way to begin or return to sleep.
What you can do to help you sleep? Reading, Journaling, TV, Music, Mantras, Prayers, Breathing, Yoga, Warm Dim Lighting, Darkness; your choice, find your way for peaceful sleep.
Morning Light Exposure
Morning Light, primarily blue-wavelength light, reduces morning drowsiness. Light to the eyes is important for the entrainment (the synchronization with light days and dark nights) and a healthy circadian rhythm.
Exposure to sunlight in the morning, and during the day, leads to earlier melatonin onset in the evening and makes it easier to fall asleep. Bright morning light has been shown to be effective against insomnia, premenstrual syndrome and seasonal affective disorder (SAD).
  See SAD - Seasonal Affective Disorder page for SAD benefits of morning light exposure.
Why is 8 hours of sleep important?
Sleep Debt is the term applied to reduced hours of sleep and how it affects your body. Scientists have shown that lack of sleep can be as debilitating as alcohol.
You have two weeks to make up missed sleep, after that it will affect your health. As for jet lag, for each hour, it takes one day to acclimate to a new time zone. Match the number of hours in a different time zone and the days after before normal sleep/wake patterns resume.
Teenagers are notorious for sleeping long hours on weekends, often making up for lost sleep during the week. As growing young adults, teenagers can need up to 10 hours of sleep a night. See the table below for recommended hours of sleep for each age.
How much sleep do we need? 
REM - Rapid Eye Movement
Do our eyes move while we sleep?
According to researchers at Tel Aviv University, "The eye movements are not actually scanning your dream - they're reorienting your visual thoughts," Prof Horne told BBC News. 
For the first time, scientists have recorded from individual brain cells during the dreaming phase of sleep. After each rapid eye movement (REM) they recorded bursts of activity that match what happens when we are awake and we see - or imagine - a new image. They suggest that these well-known flickering movements accompany a "change of scene" in our dreams. 
Dreaming & Second Sleep
Sleep Gap is the time in the middle of the night when many wake and cannot sleep. Some learn that this is normal for them. Here is an article written by dream expert, Jane Carleton. DREAMING and Second Sleep
Reduce your light pollution to get better sleep and help wildlife
Published on: November 13, 2016 By Edmonton and Area Land Trust: http://edmontonjournal.com/health/family-child/reduce-your-light-pollution-to-get-better-sleep-and-help-wildlife
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