I am ending my seventh month of my year-long foundation project. The focus of this month is sleep. I will share some personal thoughts in the next post. In this post, I will share the key points in books I read and falling asleep.
For those interested, you can also read my last few months’ updates and book list here:
- healthy: Beginning, ending, books.
- productivity: Beginning, ending, books.
- money: Beginning, ending, books.
- food: Beginning, ending, books.
- read: Beginning, ending and books.
- Outreach: Beginning, ending, books.
Summary of the 3-minute I learned this month
Sleep is important. Moderate sleep loss can damage cognition, mood, and immune system. Total deprivation is fatal.
Nevertheless, we culturally devalue sleep. We bring importance to those who experience sleep deprivation, even though many cognitive tests show that twenty-four hours of rest hurts us as much as getting drunk legally.
Sleep is more than just unconsciousness. When we sleep, our brains are active. The spindle event transfers memory from the hippocampus to the cortex. Glial cells contract, allowing cerebrospinal fluid to flush the brain and remove waste. Dreams happen throughout the sleep, at the end of Rem’s sleep, the most vivid and strange things that happen during Rem’s sleep occur, although we rarely remember them because the circuit of memory is actively suppressed.
Our sleep needs are driven by two processes. First, the process s accumulates sleep stress throughout the day. It may be regulated by adenosine. Another, process C, a cycle between day and night. Process C uses melatonin to signal, requiring bright light every day during the day and dark at night to calibrate.
Ideally, these two processes synchronize to keep you sleepy at night and awake during the day. However, caffeine (temporarily blocking adenosine receptors) and indoor lighting can mess up these basic rhythms, making sleep more difficult.
Insomnia is not sleep deprivation. If you are sleepy enough, you will sleep. The most successful treatment for insomnia is actually limiting how much time you spend in bed to facilitate you to accumulate enough sleep drives so you can fall asleep quickly. Worrying about sleep is one of the best ways to make sure you have trouble falling asleep.
Scientifically speaking, despite many possible theories, we still don’t know why we need to sleep. The lack of consensus may be because sleep actually performs many different physiological functions that are staged in conjunction with our daily dormant periods.
Notes on the books I’ve read
Side note: I did not include the popular books by Matthew Walker, Why do we sleep. Please refer to this footnote for explanation.1
Insomnia is when you desperately want to sleep but can’t fall asleep or fall asleep.
The most successful treatment for insomnia is somewhat contradictory. Rather than working on more sleep (which makes you stressed about sleep and therefore hard to fall asleep), instead: limit how much time you spend in bed.
This forces you to build a sleep drive, making it easier to fall asleep. It can also help you adjust the connection between bed and sleep, rather than bed and TV, social media, or, worst of all, *try* to try to fall asleep.
One of Wu’s most surprising arguments is that those who suffer from insomnia are not usually deprived of sleep. Their quality may be poor or sleep consistency. They may feel tired and bad. But they are not usually deprived of sleep – otherwise they will naturally fall asleep.
It seems that part of insomnia itself is maintained by anxiety about the way you sleep. Trying to sleep too hard can make your sleep good!
What is the “right” way to sleep? If you were like me, I guess you would imagine something like this: You turn off the lights, enter the room alone or with other important people, and then fall asleep for eight hours in a row, rising to the alarm clock. Next comes a non-stop 16-hour activity before going to bed.
Reiss points out that this modern ideal of sleep is actually very strange compared to the way most humans traditionally sleep.
More common are two sleeping patterns: sleep for a few hours, wake up to attend some quiet midnight activities, and go back to sleep for a second time. Naps are also very common. Historically, sleep has almost never been a private matter – the entire family, including guests, usually fall asleep in the same bed.
Our modern anxiety about sleep can be traced back to the invention of indoor lighting, which cuts off our sleep cycle from the sun.
Reiss explores more of our sleep-related weirdness in his book, from the touch of parents-industrial complex, to the deep intertwined history of sleep and racism, and even the difficulty of Henry David Thoreau making Walden making Henry David Thoreau.
Why do we sleep? Science has many theories, but it is far from reaching consensus on the main purpose of sleep.
This should be an amazing fact in itself. Compare sleep with nutrition. We have not achieved perfect knowledge of nutritional science, but experts have no dispute over why they eat.
Sleep is evolutionarily expensive. It requires the animal to give up feeding, explore or mating for hours at a time, while placing itself in a position that makes it vulnerable to predators. Nevertheless, almost all animals sleep. Dolphins sleep half of their brains at a time to avoid drowning, bears must wake Hibernate their own to bring their brains to sleep. Perhaps the lack of knowledge here is disappointing. But, in our modern age, everything seems to have been discovered, theorized and explained, and I feel excited that such a fundamental question about human existence remains shrouded in mystery.
I found this to be a good general summary of sleep science, from process S and process C to four stages of sleep and what we know about its function.
One of the most interesting tidbits in this book is best practices to overcome jet lag. The key is to carefully time to illuminate the light to push the internal clock in the direction you want. Usually, night light delays your clock and daylight.
For example, a traveler who leaves New York in London after 7 hours of flight at local time (local time) for 5 hours in the UK time zone, i.e. his body still thinks it is 2pm during the flight or when landing in London, will delay his internal clock when landing in London, which is contrary to the need to adapt. So minimizing light exposure within the last few hours after the flight and at landing will speed up his adaptation to the new time zone.
Sadly, the daily rhythm requires a mild need to be exposed to the necessity of this rhythm, which means that most completely blind people suffer from bad barriers to the internal clock, deviating completely from phase every month or so, as their hyperplastic sub-cores cannot get the pulse of light needed to keep it consistent with the rotation of the earth.
Dreams are mysterious. It’s also very familiar.
Some of these may be due to the difficulty of the subject. Dreams are hard to remember, control and explain. Sleeping in a lab can distort the dreams we have, while MRI machines are noisy, uncomfortable and expensive, making bread and foam neuroscience techniques used to study countless other mental phenomena that are difficult to apply.
However, some of our misunderstandings also seem to be a direct result of the harmful effects of Sigmund Freud and his followers on the idea of dreams. For decades, although many Freud’s purpose directly contradicted the data, they had bound to the theory of dreams.
Incredibly, rapid eye movement (REM) sleep was not discovered until the 1950s. Anyone who has seen someone sleep can find such a discovery.
Hobson convincingly argues that the strangeness of dream content distracts us from dream forms. We focus on unusual things happening in dreams, looking for explanations that explain their meaning, rather than recording the differences between dream consciousness and awakening consciousness (highly visual, poor self-awareness, etc.). Hobson then associates these formal features of dreams with brain systems that are selectively activated or downregulated in dreams, believing that the actual content in the dream is largely meaningless.
In this only lecture series, Wu (also You’re sleeping) Share research around the power of nap.
The WU file cites a series of studies that can improve our mental and physical performance, which shows that during our modern 16-hour awakening, part of the cultural tradition of naps in places like China and Spain is underestimated.
Nevertheless, a nap can be a double-edged sword. Sleeping too long or too deep, you will find yourself too drowsy to function effectively afterwards. Naps can also be eaten while you are driving while you are sleeping, making it difficult to fall asleep at night.
Therefore, in order to effectively nap, Wu believes we should follow the “fast and dirty, under thirty” rule: keep it for less than half an hour to prevent going into slow-wave sleep. Wu also pointed out that naps work best when they are consistently completed by the same schedule (such as regular sleep).
Although we may still not know the full purpose of sleep, it is clear that in complex organisms, learning is one of the main beneficiaries of good night rest.
Neuroscientist Lewis reviews the basics of learning how to work in the brain, and then shares the science of how sleep consolidates, enhances, trims, and selectively deletes memories. She shared research that sleep helps enhance important information, enhance skills, abstract details and build creative associations.
She also laughs at Hobson’s theory that the content of dreams is irrelevant, which suggests some possible roles of dreams, from dialing the emotional content of our memories to managing our social lives.
8. Caffeine by Murray Carpenter
The other side of our depreciation of a culture that is sleep-enough is the elevation of chemicals, which makes us think we don’t need it. Caffeine has long been the drug of choice in our society, with coffee, tea and soda allowing us to travel through sleep deprivation.
As a drug, caffeine is difficult to judge. On the one hand, it has significant benefits in terms of cognitive and physical performance, minimal side effects and relatively high toxic doses.
On the other hand, caffeine is a drug that has physiological effects on the human body. Furthermore, it is strengthening, which means we tend to continue to consume more.
The carpenter made a provocative analogy between the free addition of caffeine and sugary beverages and the addition of nicotine to cigarettes. The former is considered a major contributor to the obesity epidemic, and it is no coincidence that soft drink companies have found that adding this mildly addictive substance to their products.
Meanwhile, caffeine is barely regulated, not only entering traditional coffee and cola, but also entering juices, supplements, and even chewing gum. We are doing global experiments to increase caffeine intake and I think Carpenter is right at least shocked by the possible downstream consequences.
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This is the book of this month. Next week, I’ll have some thoughts on my personal efforts to sleep better this month!
footnote
- I read the book “When Walker first came out.” After reading, I noticed Why do we sleep yes A hasty introduction to basic science. This is disappointing, because Walker himself is a serious researcher who works in valuable experiments. But he obviously did not prioritize the same level of rigor when conveying work to popular audiences. While I can’t guarantee the accuracy of other books I read this month, it has caused concerns Why do we sleep It’s serious and can be disqualified from re-reading this month.
