Tag: sleeping

The Natural Segmented Sleep

By Anupum Pant

Background

The light bulb changed everything. Before it came, when the only practical sources of artificial light were candles & lamps, people did not often use candles to stay awake at night. These sources of artificial light costed a lot more per lumen hour. They were not always used. They were used only when artificial light was totally necessary. Normally, as the sun went down, people preferred sleeping. As bulbs came, they transformed the way we slept. Or, so argued the historian A. Roger Ekirch.

In his detailed published anthropological work – At Day’s Close: Night in Times Past – he mentions that the eight-hour single block of sleep is a recent change in our sleeping schedule. For many many years more than we’ve slept for eight hours in the night, our ancestors had practised a very different kind of sleep schedule which became the natural way of sleeping for humans. It was a segmented sleep.

The schedule went like this…

When the sun went down, there was more or less no artificial source of light. Due to this, our ancestors could do nothing useful. Bored with inactivity, they slept. Then somewhere in the mid-night, they woke up. For an hour or so, they remained awake and went back to sleep again till the morning.

The time for which these people remained awake, was probably the most relaxing and most calm time of their lives. Due to increased levels of pituitary hormone prolactin, people felt a lot at peace during this hour. During this time, people liked involving themselves in some kind of activity. Some preferred reading, others wrote. Some smoked, others visited their friends. And so on… The point is, people found themselves replenished during this time. It was apparently blissful.

This pattern of sleep became a natural way for us humans. Turns out, the eight-hour block of sleep is not the way we always used to sleep!

This sleep pattern has been observed to come back to today’s humans when they were completely deprived of any artificial light. This can be seen in the famous experiments of a psychiatrist, Thomas Wehr.

End

That waking hour of bliss – a fact of life before the industrial revolution came – was probably a period which I feel, needs to come back to cure the modern world’s rising anxiety, stress, depression, alcoholism and drug abuse.

Some scientists believe that if you give your bodies a chance, they’d go back to a segmented sleep pattern. This is also bolstered by Wehr’s experiments. While others prescribe you sleeping pills if you tell them you wake up at night for an hour or so.

Just for the record, I’m writing this at 2:30 AM. I just woke up, and I’m off to sleep again.

[Read more]

[Mastering Biphasic sleep] A detailed blogpost on the experience by Jayson Feltner…

Darkness Is Good For You

By Anupum Pant

It is astounding how the tiniest things can affect your life greatly. Who would have thought that sleeping with lights on can change you into a completely different person, over time?

Sleeping with lights on, or simply not getting enough exposure to darkness can have long-lasting effects. Darkness is good for you.

Melatonin – The Darkness Hormone

Melatonin is a hormone found in all living creatures from the most basic ones to humans. Melatonin is produced in the pineal gland (a part of the brain), by the retina, lens and GI tract. Production of melatonin is influenced by the information received from the retina about the daily pattern of light and darkness. It is primarily secreted when the information of “darkness” is obtained by the gland.

Its Effects

Its levels vary in a daily cycle. In humans, it plays a role in the regulation of several biological functions. Three of its functions we are interested in here are – its effect on out mood, performance and aging process.

Aging, behavior and memory effects:
According to one study, in mice that were aged artificially, Melatonin had immense anti-aging effects. In a similar study, the combined effect of physical exercise and increase in of Melatonin concentration led to improvements in behavior, learning and memory.

Studies on humans have also produced results on similar lines. The hormone’s effect on mood, performance, memory and visual sensitivity were assessed among 14 healthy men in a study carried out at MIT. It was found that externally administered Melatonin had a significant but short acting sedative-like effect on humans. In terms of mood, it had a calming effect.

Anti-Cancer effects:
Melatonin causes cancer cells to self-destruct. The hormone also boosts your production of substances that make your immune system stronger. As a result, your system gets better at identifying and attacking mutated cells that lead to bad cancer.

Other effects:
Melatonin’s effect is not just limited to that. It plays a great role in decreasing Heart Diseases, Headaches, Diabetes and Osteoporosis too. And more…

Improving your Melatonin production

  • Avoid screen time during the last few hours of your day before going to bed.
  • Avoid using any sort of night-light or bed-side lamp. Sleep in complete darkness.
  • Avoid waking up abruptly due to loud alarms or bright light. Use a crescendo for alarms.
  • Sleep away from your phone.
  • Maintain a set light and dark, wake and sleep rhythm.
  • Most important of all, to optimize the production of this hormone, you need exposure to bright sunlight during the day. Unlike what just-the-headline suggests, it is important to note that you are not doing yourself any good by lying in darkness all the time. There has to be a continuous rhythm of light and darkness.
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A Bat’s Inverted Sleep Position

by Anupum Pant

I have written about sloths in the past. In that post, we appreciated the way their bodies are engineered to stay inverted for most of their lives. It turns out, a bat’s body is designed (rather evolved) in a similar way, which enables them to relax and sleep upside down. In this post, I would like to discuss – why did they evolve this way and how do they do it?

If you are interested to know more about bats, you will definitely like this post from the archives. [Bats can See]

How can bats manage to sleep like this?

Humans sleep in a horizontal position, cows sleep with their eyes open, horses sleep in a standing position, and of course, bats sleep in an inverted position. What makes an animal sleep in the position they do, is basically their anatomy – the way their bodies are designed. While sleeping upside down might seem as an anomalous behavior to us, it is a normal position for the bat’s body. Like we don’t exert energy when we are lying down, bats’ bodies don’t consume extra energy for hanging down like that.

Firstly, a bat’s claw is like a hook. A better way to understand why this helps is, to look at a converse behavior – the way a human hand works. We use up energy to contract tens of muscles and make up a hook with our fingers; this is not a normal state of our hand. Also, our relaxed hands are open where we don’t exert any energy and we sleep with our hands in that position. A bat’s claws are designed in a completely inverse fashion; they are hooked in the normal position. They don’t take up energy to make them into hooks, they are like that. And they sleep like that – which enables them to hang without using energy.
So, unlike our hands, a bats’ closed fist is their relaxed position. They have to contract tendons and use energy to open them up. This anomalous talon design allows them to hang in a relaxed position.

Bat's Talons - Normal position

Secondly, unlike every other bird, a bat can’t take off from an upright position, or from the ground. They have to be inverted to start flying. This is because they have relatively weaker wings which can’t make them fly from a stationary position. Think of an X-51A Waverider, which has to be carried on a B-52 plane and dropped down to start a flight. They drop down for a very small amount of time and beat their wings vigorously to start a flight. Since, they have to wake up inverted to go flying and catch a meal, they go to sleep like that.

Why did they evolve this way?

They’ve evolved this way to simply stay away from the predators:

  1. By hiding up in a place where not many predators would look – under a bridge, roof of the cave and dark tree canopies. Also, at places like these, they don’t have to compete with other birds for a place.
  2. And by escaping quickly in case of an attack by attaining instant flight [see above].

The Purpose of Sleep – Theories

by Anupum Pant

Did you know?

  • You can live longer without food than you can live without sleep.
  • On an average, a person sleeps for 1/3rd of his life. That means if you are 30 years old, you’ve slept for 10 years already.
  • The world record for the longest span remaining awake is 11 days. The record was set by 17-year-old Randy Gardner in 1964 when he was awake for 264 hours and 12 minutes. (Don’t try this)
  • If it takes you less than five minutes to fall asleep then very likely you are sleep deprived. It should take about 10 minutes normally.
  • You can lose up to 2 grams every minute while sleeping. That comes to about a lost Kilogram at night.

What is Sleep?

Everybody sleeps. On an average, everyday, a bat sleeps for 15 hours while just 3 hours are enough for a Horse to feel rested [How much do animals sleep – chart]. Dolphins can sleep with half of their brains active and even the smallest of worms need sleep. But, till date, scientists haven’t been able to reach a consensus on why we actually do it?

Sleep can be understood as a life sustaining activity. It can be compared to another of our important activity – eating. These strongest of the human urges – eating and sleeping – serve a nearly common purpose – quell the urges; just as eating relieves hunger, sleeping relives sleepiness.

While it is true that we may have not been able to spot the primary purpose of sleep, years of research hasn’t gone wasted. With time, we have learnt a lot more about sleep than we used to know 50 years back. There have been hundreds of practical and impractical theories on why we sleep. I’ve mentioned a few of the realistic ones here.

Purpose of Sleep – Theories

Inactivity Theory:

According to this old theory, sleep evolved out of the need to be safe. It suggests that inactivity at night is an adaptation that serves as a survival mechanism. It functions as an activity which would keep an animal safe during the time it is most vulnerable e.g. Humans are vulnerable at night because they don’t see well in dark.

This theory is easily countered using the argument: Being conscious and still, is much better way to stay safe than lying unconscious and still.

Energy Conversation Theory:

It suggests, the main function of sleep is to reduce the demand and consumption rate of energy at times when searching for food isn’t an efficient option. Some believe, that this theory is a part of the inactivity theory. But, unlike the inactivity theory, this theory has been bolstered by various experiments which prove that the consumption of energy is reduced when an organism sleeps.

Restorative theory:

It explains sleep as an opportunity for a body to rejuvenate in terms of muscles, tissues, proteins, cells and growth hormones. Also, during sleep, the body clears an accumulated molecule called adenosine from the system, and makes us feel alert when we wake.

A recent study also seems to support the restorative theory in a fresh manner. It says, brain accumulates toxins [like beta amyloid] while it is awake. The concentration of such toxins keeps increasing during waking state. The study observed an increased activity of spinal fluid being pumped into the brain in rodents (hasn’t been studied on humans yet). This spinal fluid functions as a medium to pump out toxins from the brain. This theory could be a breakthrough in the study of causes and prevention of Alzheimer’s as it is known that toxins like beta amyloid cause the disease in humans [How beta amyloid causes Alzheimer’s].

Brain Plasticity Theory:

According to this, sleep plays a critical role in brain development. Infants (age when the brain develops the most), for example, sleep for about 13 – 14 hours every day. On the other hand, the poor ability to learn and perform tasks due to the lack of sleep explains the role of sleep in adults. Since, It has been proven that brain is highly active during sleep, this theory remains the most plausible one in being able to state one of the functions of sleep.