In haunted hours, I wilt to sleep, and know that I'll be cursed in dreams. I'll drift upon Stygian streams at speeds between trickle and creep, listening for some distant screams. In haunted hours, I wilt to sleep, and know that I'll be cursed in dreams trapped down below the castle keep, until the King should come to deem me worthy of some healing dreams. In haunted hours, I wilt to sleep, and know that I'll be cursed with dreams, drifting upon Stygian streams.
For a long time, the questions of why we sleep and dream remained unanswered — or answered speculatively in ways that proved without merit. One presumes the reasons are potent because there seems to be little evolutionary advantage in spending a third of one’s life unconscious of one’s environs and paralyzed (literally in REM sleep, but for all intents and purposes in NREM sleep as one can’t respond to changes in the environment without some part of one’s brain taking note of said changes.) The good news is that Matthew Walker’s book offers insight into what scientists have learned about why we sleep, why we dream, why we become so dysfunctional without doing both, and what it is about modern life and its technologies that has created an apparent crisis of sleep loss. Walker goes beyond the science to discuss what individuals and institutions can do to reduce the harmful effects of sleep deprivation.
The downside of this book is that it’s a bit alarmist, and in contrast to many books of this nature one doesn’t get a good indication of the quality of studies reported. Some pretty brazen claims are made and the reader doesn’t necessarily know if they are preliminary and unvalidated or if they are well established. Here, I’m speaking about the studies that try to isolate out the effect of sleep loss versus all other factors (which is a notoriously messy affair,) and not so much studies that report on the physiological effects of sleep and sleep loss (which I see less reason to not take at face value.) At any rate, any reader who doesn’t fall asleep as soon as his head hits the pillow and sleep straight through 7 hours and fifty-five minutes — waking 5 minutes before the alarm — is likely to feel doomed if they take this book too seriously. And if you ever engaged in shift-work (as I have) or had an intense travel schedule, you are likely to feel that your life is permanently and irretrievably wrecked.
I know this is a book on sleep, but I think it went a little too far in marginalizing all other elements of health and well-being. Walker said that he used to tell people that sleep, nutrition, and exercise were the trifecta of good health, but he ultimately concluded that sleep was more important because diet and exercise were adversely impacted by sleep loss. I don’t disagree that diet and exercise are harmed by sleep loss, but – of course – sleep quality is harmed by lack of proper diet and exercise as well. The author later discusses research confirming this two-way street. I, therefore, have no idea why he changed his initial balanced and reasonable view with one that suggests sleep is the 800-pound gorilla of health and well-being.
The book’s 16 chapters are divided into four parts. Part I (Ch. 1 – 5) lays out what sleep is, how rhythms of sleep are established / disrupted, how much sleep one needs, and how one’s sleep needs change throughout the course of one’s life. Part II (Ch. 6 – 8) explores the benefits of sleeping as well as describing the nature of the damage caused by lack of sufficient sleep. Part III (Ch. 9 – 11) shifts the focus to dreams, and delves into what they appear to do for us. The final part (Ch. 12 – 16) investigates the many ways in which modern life disrupts sleep from blue light in LED’s to arbitrary school and work schedules to cures that are worse than the ill (i.e. sleeping pills.)
There is an appendix that summarizes twelve key changes that an individual can make to get more and better sleep. There are graphics throughout the book, mostly line-drawn graphs to provide visual clarity of the ideas under discussion.
I found this book interesting and informative. I would recommend it for anyone interested in the science of sleep or how they might sleep better, with the exception of anyone who has anxiety about the state of his or her health and well-being. While I understand that Dr. Walker wants to drive changes regarding views and policies that have been wrong-headed or deleterious regarding sleep, I feel he went too far toward suggesting the sky is falling for anyone who gets less than a perfect night’s sleep every night of his life.
like snow accumulates
what world is this
where doors are portals
processing drops to
is more sedating
the world blurs
slows to zero
This month, I skipped two consecutive nights sleep to explore the effect of sleep deprivation on consciousness. Forty-eight hours without sleep may not sound like much. A two-day fast will make you feel hungry, but is hardly a challenge for the body of a healthy individual. Of course, most people could go a few weeks without food as long as they could reduce physical activity.
Sleep may be more closely analogized to water. It’s often said that a person can go a week without water, but some people have succumbed after three or four days. The world record for consecutive time without sleep is 11 days and 25 minutes, set by Randy Gardner in 1964, but most people will experience some severe challenges after a few days, and after even one day it’s not safe to do many fairly rudimentary life tasks (i.e. driving, making important life decisions, doing any work that requires concentration.) [Note: Gardener points out that it was day three when he started to feel nausea and the challenge started to feel daunting.] My choice of two days was largely influenced by the limit of how long I could go without being productive. Into the second day, maintaining the level of concentration necessary to edit or write finished product becomes almost impossible for me and it rapidly gets worse, and I certainly couldn’t safely drive my scooter.
Unfortunately, I’m no stranger to sleep deprivation, though it was mostly in my youth. That makes it sound like I was a party-animal, though I wasn’t (certainly not by the standards of true party-animals.) In truth, in the military I started out working twelve hour night shifts, and I found I could rarely sleep more than four-ish hours per day. Later (still in the military) I worked days at a base in Georgia, but I would frequently (once, sometimes twice, a week) travel from Warner Robins to Atlanta after work for martial arts classes. Often, hanging out with friends after night classes, I would return to base in the wee morning hours and — on a number of occasions — missed a night’s sleep because I didn’t have enough time to get in even a solid two hours before I had to be ready for the 6am shift change. (Note: I’m a groggy napper. While some people swear by naps, I find they tend to make me even more fuzzy-headed — especially if I’m in need of more sleep than I have time to get.) [FYI: My personal record for sleeplessness is a little longer than I did this time — 55 hours-ish. It was also when I was a young man in the military.]
Where sleep is very different (from food or water) is that until recently we didn’t have the foggiest idea why we needed it. Biologists could tell us why we need air, water, and food decades ago, but no one knew why we needed sleep — only that bad stuff happened in pretty soon when we didn’t get sleep. I was under the impression that we still didn’t know (and it’s probably true that we don’t yet have a complete picture.) However, I started reading Matthew Walker’s Why We Sleep, and he suggests that it’s not that we don’t know why we sleep, but rather that it’s not the simple one-to-one cause-and-effect relationship that sleep researchers had hoped to discover as a Holy Grail of sleep causation. Walker says we know a great deal about why we sleep, it’s just that there are a large number of aspects of our body’s operation that hinge on sleep. In other words, it’s a complex many-to-one relationship between causes and sleep. [Another reason I kept a limit on this experience was the book’s discussion of how many adverse impacts sleep disruption can have, and — more importantly — how long-lived the effects of sleep deprivation can be.]
There were a number of ways the sleep deprivation was felt. Of course, the predominant sensation was just an incredible pressure to go to sleep, i.e. heavy eyelids, mental drift, and “head-nodding” micro-sleep. There’s a great deal of discussion about how memory degrades under sleep deprivation, because sleep / dreams seem to be heavily involved in the memory process. I didn’t notice any memory defects [any more than I might normally have.] However, I readily noticed a decline in concentration and focus. After a day without sleep, I found that my ease of proof-reading / editing was significantly reduced even when I did it during those times when I was most awake and didn’t really feel particularly sleepy. A one-hour task would take decidedly more than that, and I recognized that I shouldn’t do any finished work because even if I took twice as long I’d likely still miss mistakes. Toward the end of the second day, I had trouble even following a sitcom story on the television (thought that was at the point in circadian rhythms when I was most desirous of sleep.)
The other mental effect I noticed was a mild altered sensory perception. This was nothing like the psilocybin tea altered perception. The first thing I notice was a little bit of movement in my visual field if I zoned out while staring at at the floor (and zoning out happens much more than it ordinarily would after a good night’s sleep.) Again, this wasn’t vivid like the shrub that sinuously wound in a serpentine fashion when I tried psilocybin tea. Rather it was just a kind of tiny “stretching” of floor surface when I looked down. You’d have to pay attention for it and might rub one’s eye to try to get rid of it. The second thing I noticed was some auditory strangeness. I heard a barking dog in a passing car, and it was as if that one sound was turned up even as the car was getting further away (or perhaps like the other sounds were turned down. All I know is that the barking of the dog took a dominant position in my auditory awareness. I wasn’t anything wild, like the dog talking to me. I suspect that would take another couple days of complete sleep deprivation. And I have no particular anxiety about dogs or barking noises.)
Physically, there were a few other noteworthy effects. First, I found myself getting chilly even with no AC on and even after I turned the fan off. What’s important to note is that I tend to run hot, and in Bangalore if I feel chilly it probably means I have the flu. I’ve known for a long time that thermoregulation is disrupted during sleep. (This is why one may go to bed comfortable and wake up in a sweat puddle, or — for some, I suppose — go to bed comfortable and wake up freezing. It’s not necessarily a change in the room’s temperature, it’s that your body isn’t so much adjusting the difference between room temperature and body temperature anymore.) I found the chill interesting. The fact that I wasn’t sleeping seemed to me should have meant that reduced thermoregulation should be irrelevant. However, after the fact I learned (again in the Walker book) that body temperature changes with one’s bodily rhythms, and that is presumably what I was feeling.
Second, I noticed a very mild rumbly-tummy effect. I didn’t realize how much sleep problems can be tied into eating problems until reading about it, but I have noticed in the past that my stomach gets a sensation that is akin to being hungry if I’m on no sleep — even if I’ve not been without food (at least not more than I normally would be through the night.)
Those were the most noticeable effects. I can see why some people have had similar experiences while severely sleep deprived as during mystical experiences of other cause (e.g. hallucinations from consuming substances, severe fasting, etc.) Still, for me, the long and short of it was that sleep deprivation had (in contrast to the the other practices I’ve done in this series) a clearly negative impact on the performance of body and mind. From difficulty concentrating to a slow time when running, my body was hindered by lack of sleep. Sleep deprivation diminished my mental and physical competence with no offsetting benefit that I could determine (other than assuaging my curiosity.)
Next month’s post on experiencing altered states of consciousness will be on a mystery topic. [Which may or may not be my way of admitting I’m not sure what I’m going to do yet.]
This book is a product of the 4th Mind & Life Institute Conference that took place over five days in October of 1992 in Dharamsala, India. It reads as a narrated description / transcription of the event. The Mind & Life Institute was established as a dialogue between science and Tibetan Buddhism, and is actively supported by His Holiness the Dalai Lama—who is an important figure in the book, both asking questions of the presenters and offering clarification on Tibetan Buddhist thinking on various points. The exact subject of each conference is different, but the mind is a recurring theme. Which makes sense as Tibetan Buddhist practices of the mind are as advanced as any, and it would be of great benefit to understand them better from a scientific perspective.
As the title suggests, this conference (and the book) deal with three topics: sleeping, dreaming, and dying. This may seem like a case of “one of these things doesn’t belong,” but from the Buddhist perspective on consciousness it’s a sensible enough grouping. One can think of it this way, sleeping and dying are points at which consciousness goes bye-bye. [Although, lucid dreamers retain consciousness in REM sleep, and there are unsubstantiated claims of the ability to maintain consciousness in sleep by extremely advanced practitioners.]
There is some front matter (a forward by the Dalai Lama and an editor’s Introduction) and then eight chapters. The first chapter discusses both the Western and Tibetan perspectives on “the self,” what it is, and whether it is [real or illusory.] This topic seems unrelated to the book’s theme, but it’s a way to develop a common understanding for the rest of the discussion. If participants have different views on what a person is, mentally speaking, and what consciousness is, then it’s easy to talk past each other without even realizing it. The second chapter is an overview of what was known about sleep, principally from the perspective of neuroscience (it should be noted that neuroscience was a fairly fledgling term at that time.) The next three chapters (ch. 3, 4, and 5) are about dreaming. The third chapter is a bit unique. The general approach throughout the book is to give the understanding of science and then to compare and contrast that with Buddhist thinking. However, chapter three’s discussion is led by a proponent of psychoanalysis (i.e. the Freudian approach,) which isn’t so scientific, but is a Western philosophical approach. [Chapter one is also heavily philosophical.]
Chapters four and five delve into the subject of lucid dreaming, which is referred to as dream yoga in the Tibetan Buddhist tradition. For me this was the meat of the subject, and it was the reason that I bought the book. Tibetan practices on lucid dreaming are incomparable, and at this point science’s understanding was beginning to blossoming as well.
The last three chapters are on death, and each offers a different character. The first two emphasize Western views, but in different ways. Chapter six outlines the Christian position on death—a theological rather than scientific understanding. Chapter seven explains the medical community’s view of death. This sounds straight forward, but it’s a much more technical subject than one might imagine. What organ has to stop functioning and for how long before one is actually dead. Besides all the coma patient stories, one may be aware of cases historically in which people were discovered to have been buried alive accidentally due to bad calls by doctors. The last chapter is about near-death experiences. This is an area in which there is a great potential for differing views. While science doesn’t deny that people have all sorts of fascinating experiences such as seeing bright lights at the end of “tunnels” and out-of-body experiences, scientists tend to attribute such events to material causes. [Neuroscientists can now induce out-of-body experiences by zapping a specific part of the brain.]
There are graphics in the form of diagrams and tables in the chapters that are most technical (e.g. chapter two and chapter seven,) but they are used sparingly. There’s an appendix that describes the Mind & Life Institute, as well as a glossary that explains both Tibetan and scientific terms. There are also a few pages of end notes that will help one find related material.
The weakness of this book is clearly its age. The Buddhism probably hasn’t changed much, but the science has changed a lot. Since 1992 there has been a revolution in understanding of the brain due to advances in functional Magnetic Resonance Imaging (fMRI) and other technologies.
However, despite the book’s age, there’s a lot of thought-provoking discussion, which offers plenty of room for both scientists and Buddhists to gain a better understanding of the mind and consciousness. I’d recommend this book for anyone interested in dream yoga / lucid dreaming, or—for that matter—death.
I flicker into sleep
like a bad fluorescent.
Then, the drift, floating down.
Nothing said, nothing meant.
So ends the subway to dreamland.
In the bowels, in the dark,
below the city of my mind,
lurking in a world so stark.
In dreamland, random rules.
Any change can happen here.
A tiny flea bloats big,
the sum of all your fears.
No childhood toy is free
from being terror’s shill.
To dance you into darkness,
little Teddy fits the bill.
But here you can script flip.
If you can keep your sense.
You see the secret that few know,
your mind pays all the rent.
Lucid dreams are those in which the dreamer is aware he or she is in the dream and can interact with the dreamscape. Most people experience lucid dreaming only as a happy accident. Some people dream lucidly in their youth, but never as an adult. Some people become aware they’re dreaming under specific conditions, e.g. on a certain medication. However, lucid dreaming has been practiced in some traditions for centuries, most notably by Tibetan Buddhists (though chapters 5 & 6 demonstrate that it’s much broader than just the Tibetans.) Furthermore, having confirmed lucidity in dreams in sleep laboratories, scientists have moved to advance our understanding of the phenomena using the scientific method and by taking advantage of the latest brain imaging technologies.
Charlie Morley has written a couple books on the subject as well as giving a well-received TEDx Talk on the subject. Morley studied under a Tibetan lama as well as studying up on the science of the phenomenon.
There are eight chapters in this book. The first three chapters constitute part one, the basics. This part introduces one to the subject of lucid dreaming, considers some of the reasons why people get into it, and explains how to recognize one is in a dream. The remaining five chapters form the second part, which is about going deeper with one’s practice. The second part explores what one may see in a dream, and how one can use the experience of being lucid for self-improvement. Lucid dreaming is one of the few access points to one’s subconscious mind. The second part also charts the development of lucid dreaming in both the West and the East, as well as offering suggestions about how nutrition may help in one’s practice.
The book is written as an instructional manual, and offers “toolboxes” of techniques to help advance one’s lucid dream practice by teaching one to remember one’s dreams, understand the phases of sleep, recognize one is in a dream, achieve lucidity, and know what to do once one is lucid in a dream. These are handy summaries of the lessons taught in greater detail in the text. All of the chapters but 5 and 8 have one of these toolbox summaries. There are also frequent text boxes of strange but true facts about lucid dreaming, tips from experienced lucid dreamers, case studies, and stories used to make relevant points about lucid dreaming. There are no graphics, but they aren’t missed.
I found this book to be useful and interesting. It’s readable and logically organized. I’d recommend it for anyone interested in developing a lucid dreaming practice—particularly if one is starting from scratch. There are a number of books on the subject, but many will be too ethereal to be of value to a new practitioner, but Morley writes in an approachable fashion and organizes the book to help one get into a practice as efficiently as possible.
I awoke exuberant that I’d achieved lucidity in my dream and that I’d apparently slain a nasty character (picture Hans Gruber on a bad day)–a task that had seemed impossible before my eureka of “I’m lucid!” Only my exuberance was short-lived when I realized that Hans was also me. Do you have the courage to talk it out with your dream world nemesis instead of reacting from fear?
I was thinking that I should do a post on yoga for International Yoga Day (June 21st), but what to write about? My answer came in the wee hours of the morning when I had a minor breakthrough in lucid dreaming–also known as, dream yoga. I know this seems like a stretch because, despite “yoga” being right there in the name, this practice is much more firmly associated with Tibetan Buddhism than Hatha Yoga. But my last couple yoga posts (which were a while back on my experience with RYT300 teacher’s training and teaching a Yoga Kid’s Camp) were fairly conventional, so I’m due one that’s out there. Furthermore, I promise to try to make clear the relevance of dream yoga to my hatha yoga practice. (If you read the aforementioned posts, you’ll see that the theme of freeing oneself by managing one’s fears and anxieties is a recurring theme across all these posts. And that is the crux of the relevance of lucid dreaming to unifying mind, body, and breath [i.e. yoga.])
What is lucid dreaming? It’s becoming aware that one is in a dream as one is dreaming. One can then exert influence over the course of the dream. Maybe half of you have had this experience at some point in your lives, and so what I’m saying will not seem far-fetched. For those who don’t actively practice lucid dreaming, it’s much more common among the young, so maybe you had such dreams as an adolescent but don’t have them anymore.
For the other half, the whole idea may seem like poppy-cock. I could easily have been such a doubter. Without following a practice, I almost never remember dreams–let alone dreaming lucidly. At best, I get disappearing fragments of dreams that are ephemeral and hazy. I’m one of those people who might claim that he virtually never dreams, except that I read the science, which suggests that each of us dreams every night that we sleep long enough to cycle through REM (rapid eye movement) mode (and commonly 4 or 5 times a night.) We just don’t recollect these dreams. [However, I have had lucid dreams on rare occasions, and so my skepticism on the subject was curbed.]
Why do I practice dream yoga? While it wasn’t part of my formal hatha yoga training, dream yoga isn’t as far removed as one might think. I have been trained in yoga nidra (yoga sleep), which is an exercise that takes place in a hypnagogic state (on the edge between waking and falling asleep.) Commonly, yoga nidra is used as a deep relaxation exercise, but it can also help one to access the subconscious (as is reflected in repeating a sankalpa [a resolution] in the yoga nidra state.) Lucid dreaming is another approach to assessing the subconscious in order to see what’s going on in there and to try to make changes as necessary. Curiosity about the subconscious mind and its–largely unseen–influence on my daily life is what drew me to dream yoga. It’s just another aspect of knowing oneself and trying to expand one’s capacities of mind and body.
How does one practice dream yoga? Hardcore practitioners set alarms to wake themselves up when they think they’ll be in REM sleep. This, as I understand it, helps them reconnect with the dream when they drift back and greatly speeds the process. As I sleep with a wife who would clobber me with a brick if I set alarms for random times in the middle of the night, I’m not among those hardcore. My practice consists of three main aspects. First, I make resolutions to remember my dreams and to dream lucidly as I’m drifting off to sleep. Second, when I’m not making said resolutions, I try to just observe the subconsciously generated imagery that pops up as a witness–rather than letting my conscious mind go into its preferred mode of planning for an uncertain future. [One can tell the difference because the subconscious images don’t make a lick of sense, and–for me–are devoid of any verbal/language element–i.e. it’s all imagery.] Finally, I keep a journal in which I record any dreams or fragments that I can recall–sometimes with drawings to supplement the text (though my artisticness is lacking, to say the least.) The first and last of these are among the most common recommendations one will hear from experts.
I should point out that there are a number of books on the subject by individuals much more qualified than I. Said books give detailed guidance into how one can begin one’s own practice. One that I recently finished reading and would recommend is Charlie Morley’s “Lucid Dreaming: A Beginner’s Guide to Becoming Conscious in Your Dreams.” At some point, I’ll post a review of that book. Also, there is “Dreaming: A Very Short Introduction” by J. Allan Hobson, which I have reviewed.
As I wrote up the entry in my dream journal, I made a resolution to stop attacking the “bad guys” in my dreams and to try to understand them. Note: I don’t recommend this approach for dealing with real world axe-wielding maniacs, but I highly recommend giving it a try in one’s dreams.
Dreaming is one of the most interesting and ill-understood activities of human existence. Many of us don’t remember most of our dreams—to the extent that a number of people don’t think they even have dreams (while not completely conclusive, the scientific evidence suggests that all of us dream every night—except people who live on RedBull and 2 hours / night until they tragically die young.) However, when we do remember a dream, it’s often a vivid and profound experience. Some people dream lucidly (are aware they are inside a dream as it occurs), and a few people have lucid dreams on a regular basis. This has led people to draw all sorts of conclusions about dreams existing in a realm beyond the physical, and what not.
While there remains a lot that we still don’t know about dreams, a great deal of science has been advanced in recent decades—enough to take dreamland out of the realm of spiritual mumbo-jumbo and even away from the weak (and largely wrong) science of Freud, and into the realm of legitimate science. This book summarizes much of that science in a concise package. The “A Very Short Introduction” (VSI) series from Oxford University Press offers this type of guide for many subjects. They’re usually about 100 pages long, and give a quick and gritty rundown of the subject at hand.
This book is organized into eleven chapters covering: What is dreaming? Why the Freudian approach (and earlier dream interpretation schemes) failed? How the brain is activated during sleep? What is happening at the level of neurochemistry? Why we dream? What can go wrong with dreams? (i.e. sleepwalking, night-terrors, etc.), How dreaming relates to delirium and mental illness? (i.e. it is, after all, a state of hallucination in which we take often bizarre imagery for granted.) There’s a discussion of the new psychology of dreaming which is based in neuroscience and not on an Austrian with a pipe suggesting that it all comes down to penises and vaginas. (Hobson isn’t anti-Freud, though he does want to make clear that the psychology pioneer was quite wrong on this subject.) There’s a discussion of how learning and memory can (and can’t) be advanced through sleep. Hobson discusses the interaction of consciousness and dreams, e.g. lucid dreaming. And there’s a discussion of interpretation of dreams that is rooted in more modern thought.
An interesting feature of this guide is that the author uses his own dream diary entries as case studies to make points clear. That helps make this VSI guide a little less dry than they tend to be by their nature.
I do enjoy the VSI series. I’ve read quite a few of them, and find they are a good way to study up on a subject with a minimal of effort or pain. I also enjoyed this volume specifically. It’s certainly one of the most fascinating topics on which I’ve read a VSI, and the author doesn’t disappoint in bringing interesting facts and anecdotes to the table.
I’d recommend this book if you want to get up to speed on dreaming in a little over a hundred pages.
This book is a two-in-one. It’s a pop sci book covering the science of sleep. However, it’s arranged as a self-help guide to teach one how to get the most from one’s sleep life. It covers a wide range of sleep related issues from how to minimize jet lag to how to master lucid dreaming. It also describes the sometimes dire effects of not getting enough quality sleep. Along the way one also learns about interesting anecdotes and research that may not change your quality of sleep, but could prove interesting or useful nonetheless—such as the research that shows a strong correlation between the position in which one usually sleeps and one’s personality.
The meat of the book is divided up into eight sections (called “Lessons” in accord with the theme of “Night School.”) The first few lessons begin with general background on sleep and sleep deprivation, and cover how much sleep one needs and how one can achieve the best possible sleep life. Then the book delves into more specialized topics such as night terrors, sleepwalking, “power napping,” and the question of whether one can really learn in one’s sleep. The last couple chapters deal with dreaming (normal and lucid.)
Along with the eight lessons, there are also eight assignments. Most of these assignments are surveys that help the reader understand what will work for them best specifically—as not all sleep advice is one-size-fits-all. However, there are other assignments like a mid-course recap exam, a call to attempt interpreting one’s own dreams (as opposed to relying on the generic dream interpretation guides which the science suggests are bunk,) and a suggestion to start a dream diary—with instructions for how to go about it.
Another nice feature of the book are its boxed discussions of relevant research on such topics as segmented sleep (instead of sleeping through the night), narcolepsy, snoring, children’s sleep issues, etc. There’s also a Conclusion that reviews key information from the book in the form of a refutation of the common myths that abound on the subject of sleep, as well as a “manifesto” that repeats key elements of advice on good sleep. It’s a scholarly work, and so it include source citations.
I learned a lot from this book. Granted a lot of the advice is commonsense (e.g. sleep in a dark, cool, and quiet place), but there are plenty of not so obvious tidbits as well (e.g. red light is okay, but blue light will keep one from sleeping.) There are also a lot of fascinating stories in the book to keep one interested.
I’d recommend the book for anyone who wants to learn to improve their sleep lives.