Sleep has always held a profound intrigue for me. What is it, really? Where do we go and what is actually happening to our consciousness when we sleep? How does it achieve physical and mental healing? And is it true that the sleep process helps us to sort through our experiences, consolidate new learning into memory, and physically heal our bodies? Why is it so seriously necessary that, even with minor disruptions or deprivation, we can literally lose our mind? There are many theories, in addition to healing, restoration and memory consolidation like DNA transcription function all woven into an interdependence with the human circadian rhythm.
You might be surprised to learn that, in addition to my 10 years in DC as a political activist & 18 months working in the Office of Presidential Correspondence in President Trump’s administration, and some 25+ years in human research mostly in neuroscience (cognition, depression/anxiety, dementia, and addiction medicine) I was also a sleep medicine expert. I ran a 15 bed polysomnographic clinical research lab in Rochester, New York for several years in collaboration with one of the top 5 sleep experts in the U.S., who I had the honor of having as my mentor. And it was this sleep expert (maintaining his anonymity to respect his privacy) who himself had been mentored under the father of modern sleep medicine, Dr. Anthony Kales, at University of Pennsylvania, credited, among many other achievements, with co-creating the sleep scoring system that is still used today, and was one of the first to move the field of sleep from a research activity to a discipline within clinical medicine. It was during this time that I also conducted numerous multi-center Phase 2 and Phase 3 studies for some of the top pharmaceutical companies in the industry. I managed about 20 employees from medical doctors, psychologists, polysomnographic technicians, nurses, administrative asssistants, and medical technicians/phlebotomists. And I took great advantage of this experience and post doctoral education, to learn the fascinating world of sleep medicine.
Most every animal sleeps, including mammals, birds, reptiles, amphibians, and some fish, and, in some form, in insects and even in simpler animals such as nematodes. Humans are somewhat in the middle of the range of sleep hours compared with other mammals as you can see below in Average Daily Sleep Totals.
And it was Dr. Kales and his partner, Dr. Rechtsschaffen who described and defined the criteria for sleep stages and sleep cycles. Healthy humans sleep in five 90-minutes sleep cycles and within those 5 cycles, there are 5 stages of sleep: Stage 1, Stage 2, Stage 3, Stage 4 and REM Stage (REM = Rapid Eye Movement). Let’s take a look at the stages first and then look at the diversity and complexity of the cycles because the amount of time one spends in a sleep stage depends entirely on the cycle in which it sites. Normal aging, drugs and alcohol, and organic disease can alter the morphology an chronology of the stages and cycles as well.
The sleep stages are correlated with particular brain waves. In addition to the waking stage, here is a breakdown of the 4 stages and REM. This is referred to as Sleep Architecture and your individual sleep architecture is what we study by way of a polysomnograph (PSG) or a modified EEG study that tracks your brain wave patterns while you sleep. A normal PSG looks like this:
Let’s break down the stages of sleep and and their corresponding brain wave patterns.
Stage 1: BETA WAVES:Called Light Sleep, this is the transition between waking and sleep, muscle tone is present in the skeletal muscle, breathing occurs regularly, but eye movements are slow, and while easily awakened, there is an overall loss of awareness, thought and responsiveness. This stage lasts around 1 to 5 minutes
Stage 2: ALPHA WAVES: Still a lighter sleep, but deeper than stage 1, during this stage, your brain waves slow down and have noticeable pauses between short, powerful bursts of electrical activity called spindles and K-Complexes. The electroencephalogram (EEG) begins to reveal high voltage slow-waves. Experts think those bursts are your brain organizing memories and information.
Stage 3: THETA/DELTA WAVES: This is the beginning of Deep Sleep, characterized by even higher brain waves and more pronounced slowing. It is difficult to rouse someone from sleep, this is where endogenous human growth hormone (HGH), one of the most powerful healing forces in the world is released. Muscle tone, pulse, and breathing rate decrease and brain activity during this period has an identifiable pattern. Delta waves are known for promoting immune function enhancement.
Stage 4: DELTA WAVES: Greatest release of HGH in this deepest state of sleep with primarily super high voltage, and very slow brain waves. The body repairs muscles and tissues, stimulates growth and boosts immune function. Normally there will not be any eye movement or muscle activity during these stages, however…Sleep talking and night terrors occur during stages 3 and 4. Sleepwalking also occurs in deep sleep . Sleepwalking can be dangerous, because the sleepwalker can accidentally hurt themselves through falling or touching a sharp object.
REM: The REM stage is a sympathetically driven sleep state characterized by the presence of rapid eye movements, intermittent muscle twitches, and variations in breathing patterns. Most experts believe that in REM stage, the greatest consolidation and organization of memory occurs, especially for new learning. Because the mind is so active, through a series of chemical excretions, the body is immobile or paralyzed temporarily and in spite of the rapid brain waves, this is a difficult stage from which to be aroused. If you wake someone who is in REM sleep they will likely tell you they were dreaming.
In the next Substack I will talk about some common sleep disorders and some natural approaches to improving sleep problems like difficulty falling asleep, staying asleep, or both - and a walk through some fascinating techniques in Sleep Hygiene.
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