The scientific method is a great tool to observe the world around us and try to understand how everything works. A good scientific experiment should be objective, replicable by others, and its observations should give us a better insight into the studied phenomenon. Even negative results are relevant as they give us an opportunity to reanalyze the situation and see where we went wrong.

Communication between scientists is the key. That is why we have peer-reviewed journals, where researchers can publish their findings. Before publishing, the submitted papers are given to the number of independent experts in the field, who then evaluate how the research was done, was there any problems, and they might give suggestions to authors on how to improve their experiment, or maybe a different opinion of the results. After the evaluation and any needed corrections, if the paper is solid and experts have found that it meets scientific standards, it is published in a journal.

Research of sleep and nervous system, in general, can be quite complicated. Our brain is one of the most complex things in nature and figuring out how everything works can be quite a task. As a British philosopher Emerson E. Pugh once said: “If the human brain were so simple that we could understand it, we would be so simple that we couldn’t.”

However, the research of our minds and sleep has come a long way, and now we know many things about the importance of sleep, different sleep disorders, and how to treat them.

The History of Sleep Research and Medical Treatment

The history of sleep research and medicine can be divided into five different periods.

Phase 1: Before 1952

The first half of the 20th century and the period before that weren’t very productive when it comes to sleep research. Nightly rest was considered to be a time when the brain is shut off from the external stimuli, due to darkness and lack of noise. Scientists weren’t giving too much credit to sleep, and its benefits were mostly thought to be passive, due to the passage of time and not sleep itself. It was considered to be a pretty homogenous state of mind, and sleep architecture wasn’t studied at all.

The psychological aspect of dreams and their interpretations is the field that probably got the most attention during this period.

However, there were some notable findings during this period. Unfortunately, they happened way too early to be adequately explored by the field of sleep medicine, for instance, in 1729. Jean Jacques d’Ortous deMairan showed the presence of circadian rhythms even in the absence of environmental stimuli. Narcolepsy was first described by Jean Baptiste Edouard Gellineau in 1880. Richard Caton discovered electrical rhythms in the brains of tested animals in 1875. Hans Berger started studying brain waves in sleeping and waking humans in 1929. Unfortunately, his findings only help to fix the notion of sleep as an inactive state.

Phase 2: 1952-1970

Phase 2 began in 1952 when the scientists first observed that our eyes weren’t still during some parts, and that rapid eye movement occurs during sleep. This state was associated with the appearance of dreams, so it could have been a spark that increases the interest in sleep research.

In the years after World War II, Sigmund Froyd’s psychoanalysis was extremely popular in American psychiatry. His writings about dream interpretations and structure of “ego,” put dreams in the spotlight of interest. However, this new found link between human physiology and appearance of dreams didn’t spark too much of an interested in the years that followed.

William C. Dement carried his research in the field of sleep architecture and REM phase. He showed that cyclical stages appeared during sleep and that they are somehow related to the same cyclical occurrence of REM sleep. In 1960 he showed that lack of REM sleep lead to impairment of cognitive abilities and memory the following day. That fit perfectly with the Sigmund Froyd’s narrative that dreams are kind of a “safety valve” for the release of negative energy and emotions.

That draw attention of the other scientists and they began researching the phenomenon of sleep in the following years. Most notable findings of this period are that sleep consisted of two completely different parts, REM and non-rem sleep and that the brain stem is included in the inhibition of movement during the REM stage.

In 1965 the sleep apnea was first described by two teams of scientists. Also, the first tracheostomy was attempted, to overcome the upper airway blockage of an obese patient.

Phase 3: 1971-1980

Stage 3 began when researchers from Stanford decided to extend the field of medical treatment to sleep, patients. Before that period, people were treated during the waking state, and sleeping patients were left alone.

The Stanford University Sleep Disorders Clinic was launched in the year 1970, and it changed the way we deal with sleep problems. Researches primarily concentrated on treating narcolepsy, insomnia, and sleep-related breathing problems. They developed a series of tests for overnight sleep studies, a technique that later evolved into polysomnography, a study that is still in use for detecting sleep disorders to this day.

In 1975 the American Sleep Disorders Association (ASDA) was formed, to gather around scientists and clinicians that are involved in the field of sleep research. ASDA’s goal was to set certain standards when it comes to treating sleeping disorders and to further develop techniques for doing so.

Throughout the 1970s, the only treatment for obstructive sleep apnea (OSA) was tracheostomy. It’s a method where the opening is made on the front of the neck, and a tube is inserted into the windpipe. Sometimes, it can be attached to the oxygen supply. Unfortunately, that treatment was only acceptable for the severely ill patients, and a better method for treating OSA was needed.

Phase 4: 1981-1990

This stage is marked by the invention of alternative treatments for OSA. Uvulopalatopharyngoplasty (UPPP) was introduced in 1981. This is the surgical treatment that was popular for a few years until some valuations came and showed that it wasn’t as effective as they thought it was.

Continuous positive airway pressure (CPAP) therapy was also developed in 1981. This therapy was easy to administer, there were no surgical procedures involved, and it showed to be hugely effective. CPAP is even used in today’s treatment of obstructive sleep apnea.

Phase 5: From 1991

Scientists have tried hard to come up with better diagnosing tools, more effective treatments, and to gain a better understanding of sleep and its importance in general. They have recognized that although a lot is being done in the field of sleep research, the general public’s knowledge of it is at an inadequate level. They have dedicated their time to inform people better, and to make people who are suffering from some sleep disruption, seek medical help.

The Importance of Animal Models in Sleep Studies

Research done on animals has provided us with vital information, not only about how sleep works but about sleep disorders as well. Most common mammalian models used in sleep disorder research are some dog breeds, horses, cats, rats, and mice. Dogs significantly contributed to a better understanding of narcolepsy. There were also genes identified with this disorder in studies that included canines. Rats and mice were used to understand a lot of sleep disorders better, but also to closely examine molecular mechanisms and gene expression during sleep. There are other animals used to gain a better understanding of the regulation of sleep, sleep deprivation, and the importance of it. Those animals include a worm Caenorhabditis elegans, the fruit fly Drosophila melanogaster, and zebrafish.

Future of Sleep Research and Medicine

Even though we spend as much as one-third of our lives sleeping, we are only now realizing how important sleep is. Lack of sleep or its decreased quality can lead to increased risk of heart disease, diabetes, high blood pressure, it decreases libido, impairs memory, concentration, and learning, and it pretty much affects all of the aspects of your life. Because of that, it is essential to develop healthy sleeping habits. That includes setting a regular bedtime routine, keeping the bedroom free of distractions, and avoiding caffeine before bed.  For the best results, next to the improvement of sleep, you should also try to incorporate a healthy diet and regular exercise in your life.

A report from 2016 by Centers for Disease Control and Prevention stated that one-third of adults aren’t getting enough sleep. And those tired people cost the American industry over 400 billion dollars each year due to work-related accidents.

A HealthyPeople 2020 initiative, started by the government, listed four goals related to sleep:

  • To increase the proportion of people with OSA who seek medical attention. It is estimated that 25.6 percent of people who experience symptoms of OSA sought medical help. The goal is to raise that number to 27.8 percent by 2020.
  • To reduce the rate of vehicular crashes that are due to drowsy driving. 2.7 accidents per 100 million miles traveled were estimated to be the result of drowsy driving in 2008. The objective is to get to 2.1 by 2020.
  • To increase the proportion of students in grades nine through 12 that get enough sleep. Sufficient sleep is crucial for the development of children and adolescents. It is needed for adequate physical as well as mental growth. Only 30.9 percent of students reported that they had enough of sleep on an average school night, meaning 8 hours and more, and the goal is to increase that to a 33.1%.
  • To increase the number of adults who get sufficient regular sleep. 69.6 percent of adults in 2008 got enough sleep, meaning that those between 18-21 years got 8+ hours, and those who are 22 and over got over 7 hours. The objective is to raise that proportion to 70.8 percent of all adults.

There is still a lot to uncover when it comes to sleep. It is hard to predict where the research might go next, but there are a few areas that need special attention. The link between sleep, memory, and learning needs to be studied further. It is interesting to see if sleep affects the overall intelligence of individuals and to find out exactly where are memories stored. The mechanisms on a cellular level could give us a better understanding of this phenomenon.

The link between mental disorders and the lack of sleep is another point where additional research is needed. These two seem to go hand in hand, but is it an only causational link or is there a correlation between the two?

There is also a need to look further into molecular mechanisms on the cellular level and to determine if sleep is only a feature of multicellular organisms, or is there any archaic mechanism, that might have affected a later evolution of rest throughout the animal kingdom. Animal models, especially genetically modified animals could help us shed more light on mysteries of sleep. Lastly, the big question is how we can improve sleep medicine and can we personalize it to fit every single individual?

One thing is sure; the technology is the future of sleep research. Current overnight studies done on people are taking place in sleep clinics, where people may not feel comfortable, and it may not paint the best picture of their sleeping habits. With the progress of technology and sleep trackers, in particular, we might be able to better detect sleep disorders in our own home. These small devices need to be improved to identify more things and to get to a golden standard level which is polysomnography at the moment. But we are getting there. And when those devices become widely available, that will give sleep experts more data, which will lead to more improvement in treatments.

 

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