Tuesday, February 24, 2009

Sleep Deprivation: Part 1

Not getting enough sleep is common to all of us. This happens when our body’s natural rhythm gets out of sync for a variety of reasons. This is most dramatic when we cross time zones while traveling by jet. Some nights we have a lot on our minds and will worry for a few hours before falling asleep at our regular time. Inactivity can also contribute to occasional sleeplessness. Studies show that over half of us occasionally experience loss of sleep.

Sleep deprivation refers to a condition that is much more chronic. When loss of sleep interferes with our normal activities it is called sleep deprivation. As you can guess, parts of our brain need to rest during sleep. When your brain sense it needs to rest, it will begin to shut down for very short periods of time which is called microsleep. Microsleep only lasts a few seconds Maybe you have experienced this as your head droops during a boring lecture or when driving late at night. The microsleep is sending you a signal that says "if you don’t give me more sleep soon, I’m going to shut down completely." Many traffic accidents are caused by ignoring this brain message.

Ironically, some people have the mistaken belief they can train themselves to live on less sleep than they normally get. This is different than a few individuals who are somehow born needing less sleep. One disturbing study found that people who consistently get less than four hours of sleep are prone to dying within six years at a rate three times greater than people who get more sleep.

What is Normal Sleep
Before we look further at sleep deprivation, let’s try to understand more thoroughly what sleep really is. Over fifty years ago, sleep researchers discovered that we all go through five different phases when we sleep. The first phase occurs before we actually go to sleep and is called the Waking Stage. It sounds strange that being awake is actually a sleep phase. This occurs when you begin to feel sleepy because your body is preparing itself for falling asleep. Several things happen here. As your body begins to prepare itself, your muscles begin to relax and your eye movement begins to slow down.

Next, your body enters what is called Stage One sleep. This begins when drowsiness sets in and your eyes finally close. This usually lasts about five to ten minutes. Even though this is a sleep stage, if you are awakened you may not feel as if you have really slept. Those of you who practice a muscle relaxation exercise or meditate will recognize this as the stage you experience when you are fully relaxed. Some people in this stage may have a sense of falling followed by sudden muscle contraction.

When your muscles begin to tense and relax (and you are not aware of this) you have entered sleep Stage Two. Now your heart rate slows down and your body temperature drops. This stage gets your body ready for deep sleep.

Stages three and four are similar except stage four is more intense. You may have heard of these stages referred to as delta sleep or slow-wave sleep. It is called slow-wave sleep because your brain patterns on an electromyogram show brain waves that are very slow.

These four stages generally run about ninety to a hundred and twenty minutes. Up to this point you have not yet been dreaming. Interestingly, you don’t immediately dream after stage four. It appears that after stage four you go back to stage three, then two and finally dream sleep. This complete forward-backward cycle occurs several times per night and can take anywhere from ninety minutes to two hours. When you dream your eyes move very rapidly so it is called REM sleep – REM stands for rapid eye movement. This sleep stage was not discovered until 1953.

As the night wears on, most of your sleep stays in the first two stages with some REM sleep thrown in. Some scientists think the brain does this in order "to create the healthiest possible balance to prevent fatigue and irritability during waking hours."

When you begin to dream a lot of changes take place in your brain and body. Even though your brain patterns look like stage one sleep, you will now display the telltale sign of dreaming: rapid eye movement (REM). Prior to this, much of your body functions have slowed down. Now your breathing and heart rate speed up and become irregular. If someone was watching, they might see twitching in your legs, face, or fingers. For most people, REM sleep is experienced about three to five times each night.

Here is the interesting piece about REM sleep: your major voluntary muscle groups become paralyzed. Why is this? Most scientists believe this is a safety factor built into the brain. When your muscles and brain are activated, the likelihood that you will act out your dream increases. As you can imagine people acted out their dreams while asleep (like driving a car) would have less chance of passing on their genes. They would probably take themselves out of the gene pool.

In this sleep stage a couple of interesting things can take place. If your brain doesn’t shut down your muscles, you may begin to sleepwalk (technically called somnambulism). People have done some amazing, silly, and dangerous things while in this state. While sleepwalking takes place when you are fully asleep with fully operating muscles. The opposite can also occur when you become awake while your body is still paralyzed. This experience is called hypnopompic sleep. This paralyzed-awake experience can also occur before fully falling asleep and is called a hypnogogic experience. Both are referred to as an HHE (hypnopompic-hypnogogic experience).

Best estimates are that twenty to thirty percent of the population may experience some form of this HHE brain state. Sometimes it is remembered and sometimes not. When experienced it can be frightening if you don’t know what is happening and why. No matter how scared you are, you cannot move or speak. It is usually fairly short-lived, no more than a few moments. Strange things can happen during these few moments when time seems to stand still. It is common for people to report some kind of "presence" that is threatening or even an "evil" presence. This presence is usually felt to be close by and may seem to be standing near or sitting on the bed watching or monitoring you. Some of the many experiences that accompany this is feeling is one of being strangled, attacked and having vivid hallucinations. Some people even report an out-of-body experience (OBE) like floating near the ceiling of the room. Even after the event is over, there can still be a sense of anxiety. From this description you can now understand how the idea of the incubus became popular in medieval Europe. In more modern times, we now know that alien abductees are those who have experienced an HHE.

So what’s the purpose of this back and forth activity in your brain during sleep. The answers are just beginning to appear. Many studies have lead researchers of sleep to think that one of the major functions of sleep is related to memory processing. Some studies have shown that sleep is responsible for allowing you to keep new memories. During sleep the brain can actually make new synapses and connections between brain cells.

Causes of Sleep Deprivation
So, why are so many people sleep deprived when sleep is so terribly important for health and well-being? It seems there are many reasons. Many people tell researchers their lives are so fast paced that they simply don’t have enough time to get everything done, let alone get enough sleep. Many contemporary societies value productivity. This can put sleep at the bottom of one’s personal priority list. Since most people (especially younger adults) are not aware of the detriment of sleep deprivation, they just accept being tired thinking they will catch up on the weekend and all will be well.

There are also a series of medical reasons for sleep deprivation that are called sleep disorders. One of the most common is sleep apnea. Many people who have this condition don’t even know they have it and just feel tired all the time. My co-author of The Worry Free Life had this condition for most of his life. When we went on a book tour, I was awakened one night in our motel room by the sound of a chain saw. I realized it was Pat snoring. As I listened I guessed the noise was more than snoring because there would be long pauses where it seemed he had stopped breathing. We talked about it the next day and he eventually found a physician and had surgery for the condition. After that, Pat reported he had never felt so refreshed. Sleep apnea is not only annoying but it can be dangerous by raising a person’s blood pressure.

One of the major psychological reasons for sleep deprivation is insomnia caused by worry. Most of us have some insomnia now and then. When it becomes more frequent, it is time to do something about it. Those of you who are using the tools in The Worry Free Life already know how to do this. Most of my clients have learned to sleep well by using a combination of the three stress reduction exercises and Voice Fighting.

Suggestions for combating insomnia include issues like depression, being overweight, or eating and drinking too much prior to sleep. The bottom line for all these suggestions is to change your thinking. If you remember the Domino Effect (page 25) you will also remember that behaviors are usually preceded by feelings that are caused by thought patterns. Worry is just another word for destructive thinking (or as we refer to it, the Voice).

Why is sleep deprivation so bad?
Research has shown that a lack of proper sleep translates to problems of poor concentration, increased irritability, and a decrease in school and job performance. Sleeplessness can also increase your vulnerability to certain illnesses because of a less effective immune system.

We mentioned traffic accidents resulting from sleep deprivation. The National Highway Traffic Safety Administration estimates that more than 100,000 crashes each year are a result of drivers falling asleep at the wheel. This is because the brain begins to lose its ability to function at an appropriate level: malfunctioning of your brain neurons that have a drastic effect on perception and reaction time.

Being able to use language effectively more difficult as you get less sleep. Severe sleep deprivation can basically shut down all activity in your brain. What happens to your behavior when this condition sets in? The answer is, lots of nasty things. You can begin to slur your speech just as you would if you were drunk. One study found that if someone drives after being awake more than seventeen hours he or she will drive worse than someone who has a blood alcohol level of .05 percent – the legal limit for drunk driving. In addition to slurred speech, you may stutter, speak slower and in a monotone voice. Even if your speech sounded normal to you, you would still have trouble speaking intelligently. Instead of creatively using a rich vocabulary to express yourself, your brain would choose simple phrases that were clichéd and repetitious.

Another study found that reaction time was significantly impaired. When you are sleep deprived, you lose your creative ability for making logical decisions quickly. No wonder accidents and sleep deprivation are related. This is even made worse because your ability to multitask becomes less efficient. One of the most pernicious accidents occurs in hospitals when residents don’t get enough sleep (working to much with too little sleep has typically been one of the rites of passage for new physicians). Several studies have found out that sleep deprivation increases the number of medical errors in medical settings to increase dramatically. This is why I politely grilled my surgeon before my LASIK eye surgery. "Did you get enough sleep last night?" "Any major stresses with your family?" Only after she answered all my questions to my satisfaction did I let the surgery begin.

If you are person who has difficulty with focusing, attention and impulse control, sleep deprivation will only make these conditions worse. Well, what about stress? This, too, can be a problem because lack of sleep can increase your body’s production of stress hormones.

A sleep deprived body will begin to slow down the facility for metabolizing glucose. This can lead to early-stage diabetes type-2. As you can probably imagine, if the body does not metabolize sugar well, obesity will be more likely. This is exactly what one study found – the research suggested a link between sleep deprivation and weight gain. This problem then becomes a vicious circle because weight gain increases the likelihood of sleep apnea which increases the probability of sleep deprivation, and so on.

Is this the end of the bad news? Nope. If sleep deprivation continues too long you can experience hallucinations, temporary insanity or even death as your system shuts down.

To be continued Friday

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