How much do you know about sleep? Considering that we as humans spend almost one-third of our lives sleeping, knowing what the heck we are doing while sleeping might be important. Most of us are aware to some degree that some of the time while we sleep, we dream. Some people dream about people and things in their daily life, while others of us are dreaming about anything but our daily life. Our dream time is only a portion of our sleep time. Even though we are unaware of it, our brain is very busy during the night. Our body might be resting and repairing itself in preparation for the upcoming day, but our brain is all sorts of busy.
I just finished the book Why we sleep by Mathew Walker Ph.D. He is the director of the sleep lab at UC Berkeley. It is an excellent book and his writing is both engaging and understandable, a difficult achievement when writing about such a complex subject. It is amazing how many different things have been learned about sleep considering your study subjects can’t respond to your inquiry as they are asleep. Some pretty clever studies have been invented to get around this limitation.
One of the things that most intrigued me was the studies on sleep and creativity. History is full of examples of famous discoveries made by scientists and others that literally were revealed to them in a dream. Through some very clever experiments, sleep researchers have unveiled some of the how and why of this process. During our waking hours, our mind functions in a very logical way in forming associations between our current experiences and our historical experiences. We use contextual cues much like how books in a library are arranged. But in our dreams, all that logical association process gets tossed out and we make associations between bits of information in really wild and different ways. This is why our dreams are so crazy sometimes. It is from these crazy associations that much of our creative content is derived.
One favorite technique that sleep scientists like to use is to expose subjects to a lot of information or pictures and then test the subjects 12 hours later to see how much they remember or how many creative associations they are able to make from that information. They compare folks that are given information in the morning and then tested 12 hours later in the day to folks given information late in the day and then allowed a good night’s sleep before testing them. As you might have guessed already, those folks that had a good night’s sleep showed way more associations and much more creative connections compared to those that were tested later in the same day.
That sounds pretty cool and all, but how does that help the majority of us that are not creative geniuses? The answer to that question may not be what you expect. We live in a really complex world filled with really complex creatures called human beings. The research suggests that we all require a good dose of creative genius just to get through the average day. How do we know this? We look at people who have been deprived of sleep, particularly the REM dream sleep where this type of processing takes place. When a person does not get the quality dream sleep they need, they go nuts. It starts with a simple slowed cognitive processing and a decreased ability to understand other people’s viewpoints. The ability to accurately assess risks also quickly diminishes. As the length of time without dream sleep continues, these changes turn into outright irritability and aggressiveness and ultimately full-blown psychosis and paranoid schizophrenia. This has been found even though the subjects technically got “enough” sleep for the body to restore itself, however, the REM dream sleep was simply suppressed.
Why do we know this kind of stuff? Who would conduct such experiments that would drive subjects to such extremes? One of the high-priority goals of our military has been to develop super soldiers that do not need sleep or very little sleep. They have been a source of much sleep research over the years. A little closer to home, since Sacramento is considered the methamphetamine capital of California, is the consequences of using meth. Meth addicts stay awake for days. The symptoms seen in meth addiction are largely due to a simple lack of proper sleep. How might this affect you? Many insomnia drugs and over-the-counter sleep aids (think Ambien) suppress REM sleep. How about those super popular anxiety drugs and anti-depressants like benzodiazepines and SSRIs? They also suppress REM sleep. We are not talking about just a few guys testing out how to become super soldiers. We are talking about major portions of our population having their sleep scrambled with drugs. We are talking about those folks in the car next to you on the freeway and your co-workers at work. Yes, many of them are edging close to the fast track to crazy town.
Let’s change focus and attend to the part of sleep without dreams. This is creatively called non-REM sleep so we don’t confuse it with REM sleep. (In case you were wondering, REM refers to the rapid eye movements that take place while you are dreaming.) When they monitor your brain waves during this phase of sleep, they notice large spikes of rapid electrical activity that travel from the hippocampus area of your brain (where your short-term memory is stored) to various other areas that hold long-term memory of different types. In a previous article on sleep, I wrote how sleep is essential for the consolidation of your memories from the day. That means sleep is essential for moving your memories to where you can retrieve them at a later date. If you study for an exam but don’t get a good night’s sleep that night, you lose most of what you have studied – down the drain. It appears that those large spikes (called sleep spindles) are the movement of that memory information being transferred into long-term storage. Two things about this process stood out to me in the book I just read.
One: most of this spindle formation happens at the end of your night of sleep in the last couple of hours. That means this happens during hours 6 and 7 in your sleep cycle. If you are not getting a full 7 ½ to 8 hours of sleep every night then you are missing out on this memory storage. Sleeping 6 hours or less per night is now known to be a causal factor in eventual Alzheimer’s.
Two: Alcohol consumption screws up sleep spindle formation for several days. Even one drink messes with your memory. So far this has only been measured out to 4 days of impact, but they really don’t know how much longer beyond that it will affect you. And obviously, the more you drink the worse the impact is.
This country is in the middle of a sleep deprivation epidemic. I have written about how to improve sleep by eliminating blue light sources in the evening, not eating anything in the 3 to 4 hours before going to bed, and being sure that your bedroom is cool at night. Check it out here. There are many other suggestions in the book that can help restore you to a healthy sleeping schedule.
One last bit that stood out to me had to do with the timing of our sleep cycle, called our circadian rhythm. As babies, we need 12 to 15 hours of sleep. As pre-teens, we need about 10 hours. But when we become teens, our cycle shifts to sleeping 8 hours but later, like midnight to 8. Then as we age our sleep cycle starts earlier and earlier until we are heading for bed around 9 at night. We naturally get up earlier as we age, but teens are meant to sleep in late. Forcing them to get up early for school is a bad idea. The symptoms of ADHD are the same as the symptoms of sleep deprivation. Are we crashing our kids’ futures by trying to force them to match an artificial school schedule? Just a thought.
This is just a highlight of a few of the bits that stood out to me, but there is a ton more in this excellent book. Check it out.
Take care,
David