Advertisement

Deepak Chopra and Intent

Deepak Chopra and Intent

Sleep: A mystery at the crossroads of neuroscience (Part 2)

By Deepak Chopra, M.D., FACP, P. Murali Doraiswamy, MBBS, FRCP, Professor of Psychiatry, Duke University Medical Center, Durham, North Carolina

 

In the last post we saw how essential sleep is for the physiological needs of  almost all animals, but sleep would seem to be a poor survival trait as far as evolution goes.  Because sleep put our ancestors (and other living creatures) at risk from predators, the benefits must outweigh the risks –that’s all that scientists can manage to agree on. Unlike humans, some animals (e.g., newborn dolphins) can survive sleep deprivation for a couple of weeks without apparent harm.  However, in most species, after extended sleep deprivation their body temperature and metabolism becomes unstable and they die.  The longest period a human has survived sleep deprivation is believed to be about two weeks, but many physical and mental deficits occur long before that; driving ability is significantly impaired after one night’s bad sleep.

Advertisement

Since the brain remains active in sleep, some of the proposed roles for sleep make it into a time to restore, repair, conserve energy, or all of the above. Besides the mouse study cited previously, the fact that toxins build up during sleep deprivation also suggests that the human brain clears toxicity in sleep. Another clue: Sleep increases the number of repair cells (oligodendrocytes) in the brain. Even though Freud’s dream theories have been discredited, which has also led to total disagreement about the psychological import of dreams, sleep may be a time for rehearsing what we learned during the day and archiving our memories – much like the librarian who works after the library is closed to reshelve books so that they are easy to find the next day.

Advertisement

As things stand, we know considerably more about sleep deprivation than about sleep itself. Subjects deprived of sleep do poorly on a variety of cognitive tests, and sleep deprivation is clearly linked to more accidents and errors. People underestimate how much is lost by having bad sleep. There is evidence that no daily rhythm is more important. It used to be thought that sleeping in on the weekends doesn’t actually work to overcome sleep deficit during the week, but this has been challenged recently by a finding that a sleep deprived person can enter REM sleep with a short nap, not the hours that researchers once thought were necessary.  The best guess now is that you can be fully alert for 5 or 6 hours right after you wake up from less than 8 hours’ sleep but that after this grace period, deficits will begin to show up.

Advertisement

Finally, sleep is related to mood – strangely enough, sleep deprivation can make people happy and sometimes manic. Decades ago doctors took advantage of this fact in trying to treat depression (a misguided strategy, now that we recognize the link between depression and bad sleep). For some reason, people with depression often go into REM sleep (and dreaming) more quickly than normal. But if that is symptomatic, a different link suggests that dreams can lead to creative insights, not to mention the kind of dreams that make us feel elated.

Numerous creative breakthroughs have been attributed to dreams, such as the tune for the Beatles song “Yesterday” (Paul McCartney), the structure of carbon and benzene (August Kekulé), and the sewing machine (Elias Howe).  Indeed, the discovery of acetylcholine, a chemical that regulate  many aspects of dream sleep, reportedly came to Otto Loewi in dreams on two consecutive nights in 1921. On the first night he woke up and scribbled down some notes in his diary that, alas, he couldn’t read in the morning. On the second night he was lucky enough to write them more legibly.  Loewi’s subsequent experiment based on his dreams won him a Nobel Prize.

Advertisement

Dreams can be induced by taking certain drugs (e.g., ones that boost acetylcholine or serotonin) or withdrawing other drugs (e.g., sleeping pills), so we know that dreams have a chemical mechanism. Likewise, we know that many commonly used substances, such as alcohol, cough-cold syrups, some blood pressure medicines, antidepressants, and energy drinks, suppresses REM sleep, although no one has looked at how this affects long-term creativity or memory. In a rare condition called familial fatal insomnia people lose their ability to sleep and develop a form of early onset dementia.

Do we have to restrict dreams to one purpose only, whatever current theories think it may be?  In various cultures and seen through different eyes, dreams are prophetic, messages from the gods, the tickling of the muse, random neuronal firings, and of course Freud’s “royal road to the unconscious.” And we have no way to determine categorically if other species also dream, although they must, given that REM sleep occurs in so many mammals.  (Who hasn’t seen a dog growl and writhe in its sleep and surmised that it must be chasing a cat in its dreams?)

Advertisement

So despite five decades of modern neuroscience, we have only a very limited knowledge of the role of sleep and barely know anything about the role of dreams.   Common experience tells us to agree with Shakespeare’s simple conclusion that sleep “knits up the raveled sleeve of care.”  Readers of ancient Vedic texts from India may accept that sleep is a time for inward knowing and subtle experiences in consciousness. Modern skeptics may declare that no such esoteric knowledge exists and that dreams are junk bins for the detritus of the working brain.  Without a fuller understanding of consciousness itself, however, such arguments are adrift in the same darkness we inhabit every time we fall asleep.

 

Deepak Chopra, MD is the author of more than 75 books with twenty-two New York Times bestsellers including What Are You Hungry For?  

P. Murali Doraiswamy, MBBS, FRCP, Professor of Psychiatry, Duke University Medical Center, Durham, North Carolina and a leading physician scientist in the area of mental health, cognitive neuroscience and mind-body medicine

Advertisement
Comments Post the First Comment »
post a comment

Post a Comment

By submitting these comments, I agree to the beliefnet.com terms of service, rules of conduct and privacy policy (the "agreements"). I understand and agree that any content I post is licensed to beliefnet.com and may be used by beliefnet.com in accordance with the agreements.



Previous Posts

Physics' Split Personality: Is the Dark Side Winning?
By Deepak Chopra, MD, and Menas Kafatos, PhD   For some time now most of the universe has gone dark. This startling news was brought to popular attention in a June Op-Ed piece in the New York Times called "A Crisis at the Edge of ...

posted 12:32:11pm Jul. 27, 2015 | read full post »

Mindful Evolution: Can You Guide What Your Genes Are Doing?
By Deepak Chopra, MD and Rudolph E. Tanzi, PhD   Human beings are unique in the scenario of life on Earth--that much is obvious. We are guided by awareness, and to implement our wishes, dreams, and inventions, the higher brain ...

posted 11:49:40am Jul. 20, 2015 | read full post »

From Facts to Meaning, Through Beauty
By Frank A. Wilczek, PhD and Deepak Chopra, MD Science tells us what the world is, not what it means. As expert as they are at collecting and analyzing data, most modern scientists tend to shy away from the question, "What does it all mean?" ...

posted 10:54:48am Jul. 13, 2015 | read full post »

A New Hot Button: Consciousness-Driven Evolution
Science is meant to be the opposite of a belief system. No one underlined this point more securely than Charles Darwin, who devised a theory of evolution that defied the strongest belief of his time, the all but universal belief in the bible ...

posted 11:12:21am Jul. 06, 2015 | read full post »

How to Make Quantum Reality Our Reality: Looking for a Better Deal
  By Deepak Chopra, MD and Ruth E. Kastner, PhD   If you ask a scientist to talk about quantum mechanics, it’s predictable that the first thing he or she is likely to say is that this is the most successful theory in the ...

posted 11:08:03am Jun. 29, 2015 | read full post »

Advertisement


Report as Inappropriate

You are reporting this content because it violates the Terms of Service.

All reported content is logged for investigation.