Some Stuff I Just Learned About Sleep, Such as Why We Need More and Why We Don’t Say About a Problem That “I’ll Stay Awake on It”

It’s been a while since I’ve listened to one of Alan Alda’s “Clear + Vivid” podcasts. They never disappoint.

In this episode, Alda interviewed sleep researcher Matthew Walker, a professor of neuroscience and psychology, the author of a best seller titled Why We Sleep, and the host of an eponymous podcast. As usual, the interview piqued my interest to look further as well.

The Matter of Ambien and Its “Brethren”

Alda’s first question arose from his own insomnia: he’d taken an Ambien the night before. Was that OK?

Walker’s response was gentle: he seems to understand the pressures his field creates in people.

“I’m not the biggest fan of Ambien and its brethren,” he said. Such substances sedate the brain and don’t produce naturalistic sleep. His research has even found when they map deep sleep on images, there’s a “signature dent…that is perhaps undesirable.”

Walker did, however, express enthusiasm for drugs called DORAs: dual orexin receptor antagonists. Researchers found that this neuropeptide is deficient in the brains of people with narcolepsy.

They fall asleep during the daytime because they don’t have enough orexin to “flip the light on wakefulness of the brain. Insomnia is the reverse problem: people need to get sleepy at night.”

Thus, some clever folks working in pharmaceuticals “reversed the chemical equation.”

By blocking the peptide that turns off the brain’s wakefulness light switch, they enable “naturalistic sleep to come to the brain rather than inhibit it.”

To Nap or Not to Nap?

Napping, according to Walker, is a “double edged sword.” Brief naps can be very beneficial, but if we sleep longer than twenty minutes, which means we’ve reached the deeper stages, and wake up not feeling fully awake, the nap may negatively affect our night’s sleep.

During the day, the sleepiness chemical increases, but napping releases the pressure to sleep and with it, the “healthy sleepiness” that would follow later.

Alda asked Walker about the inventor Thomas Edison, who was known to be a habitual daytime napper. Walker said Edison understood the power of sleep to foster creativity.

He described Edison’s modus operandi, which—I learned subsequently—actually first appeared in an 1889 interview in Scientific American, and was described again in that publication in 2021.

The more recent article described Edison as being “famously opposed to sleep.” Edison “claimed he never slept more than four hours a night. Sleep was, he thought, a waste of time.”

Whether he didn’t sleep because he couldn’t or chose not to, he used his daytime napping productively.

Sleep and Creativity

Edison, Walker observed, would “take steel ball bearings in his hands” and place a metal plate on the floor at his sides. Then he’d relax. As he slept, he “released the steel ball bearings, [which would] crash onto the metal plate. He’d wake up and write down what he learned.”

His house was filled with nap cots so he could rest wherever he was.

According to that Scientific American piece, Edison seemed to know intuitively something that sleep researchers have learned fairly recently: “We have a brief period of creativity and insight in the semi-lucid state that occurs just as we begin to drift off to sleep.”

The Scientific American article pointed to sleep studies done by Delphine Oudiette of the Paris Brain Institute and her associates.

Odiette has said that, like Edison, she was motivated by her own experiences.

“I’ve always had a lot of hypnagogic experiences, dreamlike experiences that have fascinated me…”

Though she was surprised to learn how little research has been done in recent years on the topic, she described historical precedents that I also found fascinating:

“‘Alexander the Great and [Albert] Einstein potentially used Edison’s technique, or so the legend goes,’ she says. ‘And some of the dreams that have inspired great discoveries could be hypnagogic experiences rather than night dreams.

‘One famous example is the chemist August Kekulé finding the ring structure of benzene after seeing a snake biting its own tail in a ‘half-sleep’ period when he was up working late.’

‘Surrealist painter Salvador Dalí also used a variation of Edison’s method: he held a key over a metal plate as he went to sleep, which clanged to wake him as he dropped it, supposedly inspiring his artistic imagery.”

The Oh-So-Important Physiological Aspects of Sleep

Walker noted that early stage sleep is called N1. We’ve all heard of the august REM sleep—for rapid eye movement—which is the powerful time when most dreaming occurs. N1 is the first of four non-REM stages that both humans and other mammals experience.

Researchers have unimaginatively, as Walker pointed out, named them N1 through N4, for non-REM as opposed to REM.

The first two stages are light sleep; the second two are deeper. REM dreaming then occurs.

So the first part of the night is non-REM sleep, but the second part is predominantly REM sleep.

Here’s a puzzle: Walker described a “battle for domination throughout the night; a cerebral war won and lost every ninety minutes and replayed every ninety minutes.”

Why this epic nightly battle, which makes me exhausted just to contemplate?

“We don’t know why.”

Nevertheless, sleep researchers can do amazing things in their search for causality, even if they haven’t answered all their questions.

They can, for example, “excise your deep sleep at night, wipe out the deep sleep or REM, [then] measure the consequences.”

I do not know how they do that, and I couldn’t find a reference, but this capability sounds both impressive and a tad eerie, doesn’t it?

As a result, they’ve learned that deep sleep saves and strengthens our memories. It is also essential for what Walker calls “refreshing our short term system.” He likens the process to transferring files from a USB stick to a computer hard drive.

Critically, deep sleep doesn’t just refresh the brain. It also wafts into the body and “restocks the weaponry in the immune arsenal; we wake up more immune.”

The cardiovascular benefits include relaxing the blood vessels, slowing the heart rate, and reducing blood pressure and cortisol levels—all “wonderful for cardiovascular health.”

Another critical element involves regulating our blood sugar by resetting insulin and glucose.

If our breakfast involves scarfing down a large bowl of porridge (in my case, steel-cut oatmeal), a “deep sleep…helps the cells suck up blood sugar so you don’t get a dangerous spike.”

Why “Let Me Sleep on It” Is Not Off the Mark

If so much important stuff is happening during N1-N4, why is REM fighting for dominance?

Walker spoke of the work of William Dement of San Francisco, who—I later learned—was a primary researcher in the discovery of REM.

In fact, having read a little about what a giant Dement was in this field, I think it’s worth a brief detour to tell you about his accomplishments.

He and Nathaniel Kleitman wrote a journal article published in 1957 titled “The relation of eye movements during sleep to dream activity: An objective method for the study of dreaming.”

The abstract states:

“A high incidence of dream recall was obtained when Ss [subjects] were awakened during periods of rapid eye movements (REM), and a low incidence when awakened at other times. Ss judged these dream durations with high accuracy. The pattern of the REM’s was related to the visual imagery of the dream.”

William Charles Dement, who died in 2020, is regarded as a “pioneer in sleep studies as he created the fields of sleep research and sleep medicine,” according to a tribute that appeared in Sleep Science after his death.

He began the first sleep disorders center in 1970, the forerunner organization of what is now the American Academy of Sleep Medicine in 1975, and the journal Sleep, with colleague Christian Guilleminault, in 1978.

Over the years, he was central to explaining the phases of the sleep cycle in humans and the physiology underpinning dreams. He and Guilleminault identified sleep apnea and worked to design treatments.

To accomplish their work, he developed polysomnography, which has been called the “gold standard” tool for evaluating sleep and diagnosing sleep disorders through testing levels of blood oxygen, heart rate and breathing, snoring, and leg movements.

Walker briefly described Dement’s studies concerning REM. He and colleagues deprived volunteers of sleep for six weeks.

The volunteers became erratic, demonstrating pendulum-like emotions that veered suddenly between laughing and crying. By the fourth day of sleep deprivation, they were hallucinating.

Thus, as Walker described it:

“REM sleep is emotional first aid, overnight therapy [that] takes the sharp edges off…”

Going back to creativity, how does it enhance that process?

“It takes individual new memories and collides them with a catalog of new information.”

Apparently, dream sleep helps us make what Walker calls “non-obvious, distant connections.” That’s the basis for the problem-solving expression: “I’ll have to sleep on it.” Walker emphasized that no one ever says “you should stay awake on a problem.’”

REM also affects testosterone levels in men and women and the regulation and maintenance of our body temperature.

Looking Toward Neurological Disease Prevention

Alda, who has Parkinson’s disease (PD), said he thought he’d had it years ago because he’d become aware of his physical movements during his dreams. He’s since learned that such REM disorders may be indicative of Parkinson’s, though the association isn’t widely known.

Walker explained that during REM sleep, the brain may be up to 30% more active than when we’re awake, but alpha motor neurons paralyze our bodies temporarily so our minds can dream safely and not act out our dreams. (This normal state is called sleep atonia.)

He confirmed Alda’s sense. Clinicians see the absence of REM sleep paralysis in PD patients ten to fifteen years before the onset of other symptoms. Having this REM disorder does not mean “predetermined destiny” of PD, but it “increases the risk markedly.”

Walker advises anyone who experiences this sign to see a physician, and if the physician isn’t cognizant of the connection, look for a board-certified neurologist with sleep training.

He and his team have spent the past twenty years working on the linkage between sleep and Alzheimer’s Disease (AD).

“I think it’s fair to say a lifestyle of lack of sleep—six hours or less—markedly increases the beta amyloid and tau, the toxic proteins in the brain that have been associated with AD. This is also seen in those with lifetime insomnia and sleep apnea.“

In a brain that’s been deprived of sleep–or just deep sleep–there is a measurable increase of amyloid and tau in the blood stream and the brain itself.

Walker wasn’t scaremongering, he stressed; once the pathology is understood, prevention becomes more feasible.

At this point, Walker mentioned Maiken Nedergaard, MD, DMSc, who is based at the University of Rochester, so I looked her up.

She and her team have done pivotal work on the brain’s cleansing system, which Nedergaard and her colleagues named the glymphatic system because it acts like the lymphatic system on the brain’s glial cells, flushing cerebral spinal fluid to remove waste.

In the press release linked to above, they underscore the potential far-reaching impact of their work.

“Our group believes that understanding how this process functions in the healthy nervous system holds the key to developing treatment options for a wide variety of neurological diseases, especially those characterized by the improper accumulation of misfolded proteins. The breakdown of the brain’s innate clearance system may in fact underlie the pathogenesis of neurodegenerative disorders such as Alzheimer’s, Parkinson’s, and Huntington’s disease, in addition to ALS and chronic traumatic encephalopathy.”

If you’re interested in learning more, this press release from the university summarizes the AD work and cites relevant studies.

(Nedergaard has received several prestigious prizes for her finding. My untutored scientific sense is that it will be deemed Nobel Prize-worthy at some point.)

This cleansing mechanism was found to work only when the mice slept. Two of the toxic sticky proteins it removed at night were beta amyloid and tau.

Similar cleansing occurs in the human brain during deep sleep—the later stages of non-REM sleep.

Walker offers a “word of hope.” To date, the medical approach to AD has been “very reactive—we do late stage attempted treatment rather than midlife prevention. The decline in deep sleep begins even in our thirties.” So we need to “bend the arrow [toward a] model of mid life prevention.”

Obviously, at the same time, we must continue doing research to find more effective and safer Alzheimer’s drugs for our aging population.

What Can We Do?

I’ll close by returning to the tribute to sleep pioneer William Dement. The author wrote:

“For him, the world dangerously undervalued the importance of sleep and the negative effects of sleep deprivation, and his mission was to educate and alert the world about the consequences of a sleep deprived society.”

Walker stressed that we’re going in the wrong direction, with a worldwide trend toward increased sleep deprivation.

I’m taking his concerns seriously and personally.

As I have a strong desire to further my body’s homeostasis, I found all this information fascinating and disquieting. I was left with a determination to do what I can to improve my own sleep—to bend the arrow in my own life.

That includes trying to eliminate reading things on my cell phone hours before bedtime. I don’t want that blue light to make my glymphatic system have to work even harder.

How about you? Do you have sleep concerns? If so, are you motivated to do anything about them?

Annie