فصل 15

CHAPTER 15

Sleep and Society:

What Medicine and Education Are Doing Wrong; What Google and NASA Are Doing Right

A hundred years ago, less than 2 percent of the population in the United States slept six hours or less a night. Now, almost 30 percent of American adults do.

The lens of a 2013 survey by the National Sleep Foundation pulls this sleep deficiency into sharp focus.I More than 65 percent of the US adult population fail to obtain the recommended seven to nine hours of sleep each night during the week. Circumnavigate the globe, and things look no better. In the UK and Japan, for example, 39 and 66 percent, respectively, of all adults report sleeping fewer than seven hours. Deep currents of sleep neglect circulate throughout all developed nations, and it is for these reasons that the World Health Organization now labels the lack of societal sleep as a global health epidemic. Taken as a whole, one out of every two adults across all developed countries (approximately 800 million people) will not get the necessary sleep they need this coming week.

Importantly, many of these individuals do not report wanting or needing less sleep. If you look at sleep time in first-world nations for the weekends, the numbers are very different. Rather than a meager 30 percent of adults getting eight hours of sleep or more on average, almost 60 percent of these individuals attempt to “binge” on eight or more hours. Each weekend, vast numbers of people are desperately trying to pay back a sleep debt they’ve accrued during the week. As we have learned time and again throughout the course of this book, sleep is not like a credit system or the bank. The brain can never recover all the sleep it has been deprived of. We cannot accumulate a debt without penalty, nor can we repay that sleep debt at a later time.

Beyond any single individual, why should society care? Would altering sleep attitudes and increasing sleep amounts make any difference to our collective lives as a human race, to our professions and corporations, to commercial productivity, to salaries, the education of our children, or even our moral nature? Whether you are a business leader or employee, the director of a hospital, a practicing doctor or nurse, a government official or military person, a public-policy maker or community health worker, anyone who expects to receive any form of medical care at any moment in their life, or a parent, the answer is very much “yes,” for more reasons than you may imagine.

Below, I offer four diverse yet clear examples of how insufficient sleep is impacting the fabric of human society. These are: sleep in the workplace, torture (yes, torture), sleep in the education system, and sleep in medicine and health care.

SLEEP IN THE WORKPLACE

Sleep deprivation degrades many of the key faculties required for most forms of employment. Why, then, do we overvalue employees that undervalue sleep? We glorify the high-powered executive on email until 1:00 a.m., and then in the office by 5:45 a.m.; we laud the airport “warrior” who has traveled through five different time zones on seven flights over the past eight days.

There remains a contrived, yet fortified, arrogance in many business cultures focused on the uselessness of sleep. It is bizarre, considering how sensible the professional world is regarding all other areas of employee health, safety, and conduct. As my Harvard colleague, Dr. Czeisler has pointed out, innumerable policies exist within the workplace regarding smoking, substance abuse, ethical behavior, and injury and disease prevention. But insufficient sleep—another harmful, potentially deadly factor—is commonly tolerated and even woefully encouraged. This mentality has persisted, in part, because certain business leaders mistakenly believe that time on-task equates with task completion and productivity. Even in the industrial era of rote factory work, this was untrue. It is a misguided fallacy, and an expensive one, too.

A study across four large US companies found that insufficient sleep cost almost $2,000 per employee per year in lost productivity. That amount rose to over $3,500 per employee in those suffering the most serious lack of sleep. That may sound trivial, but speak to the bean counters that monitor such things and you discover a net capital loss to these companies of $54 million annually. Ask any board of directors whether they would like to correct a single problem fleecing their company of more than $50 million a year in lost revenue and the vote will be rapid and unanimous.

An independent report by the RAND Corporation on the economic cost of insufficient sleep offers a sobering wake-up call for CFOs and CEOs.II Individuals who sleep fewer than seven hours a night on average cause a staggering fiscal cost to their country, compared to employees who sleep more than eight hours each night. Shown in figure 16A, inadequate sleep costs America and Japan $411 billion and $138 billion each year, respectively. The UK, Canada, and Germany follow.

Figure 16: Global Economic Cost of Sleep Loss

Of course, these numbers are skewed by the size of the country. A standardized way to appreciate the impact is by looking at gross domestic product (GDP)—a general measure of a country’s profit output, or economic health. Viewed this way, things look even more bleak, described in figure 16B. Insufficient sleep robs most nations of more than 2 percent of their GDP—amounting to the entire cost of each country’s military. It’s almost as much as each country invests in education. Just think, if we eliminated the national sleep debt, we could almost double the GDP percentage that is devoted to the education of our children. One more way that abundant sleep makes financial sense, and should itself be incentivized at the national level.

Why are individuals so financially ruinous to their companies, and national economies, when they are under-slept? Many of the Fortune 500 companies that I give presentations to are interested in KPIs—key performance indicators, or measurables, such as net revenue, goal-accomplishment speed, or commercial success. Numerous employee traits determine these measures, but commonly they include: creativity, intelligence, motivation, effort, efficiency, effectiveness when working in groups, as well as emotional stability, sociability, and honesty. All of these are systematically dismantled by insufficient sleep.

Early studies demonstrated that shorter sleep amounts predict lower work rate and slow completion speed of basic tasks. That is, sleepy employees are unproductive employees. Sleep-deprived individuals also generate fewer and less accurate solutions to work-relevant problems they are challenged with.III

We have since designed more work-relevant tasks to explore the effects of insufficient sleep on employee effort, productivity, and creativity. Creativity is, after all, lauded as the engine of business innovation. Give participants the ability to choose between work tasks of varying effort, from easy (e.g., listening to voice mails) to difficult (e.g., helping design a complex project that requires thoughtful problem solving and creative planning), and you find that those individuals who obtained less sleep in the preceding days are the same people who consistently select less challenging problems. They opt for the easy way out, generating fewer creative solutions in the process.

It is, of course, possible that the type of people who decide to sleep less are also those who prefer not to be challenged, and one has nothing directly to do with the other. Association does not prove causation. However, take the same individuals and repeat this type of experiment twice, once when they have had a full night of sleep and once when they are sleep-deprived, and you see the same effects of laziness caused by a lack of sleep when using each person as their own baseline control.IV A lack of sleep, then, is indeed a causal factor.

Under-slept employees are not, therefore, going to drive your business forward with productive innovation. Like a group of people riding stationary exercise bikes, everyone looks like they are pedaling, but the scenery never changes. The irony that employees miss is that when you are not getting enough sleep, you work less productively and thus need to work longer to accomplish a goal. This means you often must work longer and later into the evening, arrive home later, go to bed later, and need to wake up earlier, creating a negative feedback loop. Why try to boil a pot of water on medium heat when you could do so in half the time on high? People often tell me that they do not have enough time to sleep because they have so much work to do. Without wanting to be combative in any way whatsoever, I respond by informing them that perhaps the reason they still have so much to do at the end of the day is precisely because they do not get enough sleep at night.

Interestingly, participants in the above studies do not perceive themselves as applying less effort to the work challenge, or being less effective, when they were sleep-deprived, despite both being true. They seemed unaware of their poorer work effort and performance—a theme of subjective misperception of ability when sleep-deprived that we have touched upon previously in this book. Even the simplest daily routines that require slight effort, such as time spent dressing neatly or fashionably for the workplace, have been found to decrease following a night of sleep loss.V Individuals also like their jobs less when sleep-deprived—perhaps unsurprising considering the mood-depressing influence of sleep deficiency.

Under-slept employees are not only less productive, less motivated, less creative, less happy, and lazier, but they are also more unethical. Reputation in business can be a make-or-break factor. Having under-slept employees in your business makes you more vulnerable to that risk of disrepute. Previously, I described evidence from brain-scanning experiments showing that the frontal lobe, which is critical for self-control and reining in emotional impulses, is taken offline by a lack of sleep. As a result, participants were more emotionally volatile and rash in their choices and decision-making. This same result is predictably borne out in the higher-stakes setting of the workplace.

Studies in the workplace have found that employees who sleep six hours or less are significantly more deviant and more likely to lie the following day than those who sleep six hours or more. Seminal work by Dr. Christopher Barns, a researcher in the Foster School of Business at Washington University, has found that the less an individual sleeps, the more likely they are to create fake receipts and reimbursement claims, and the more willing to lie to get free raffle tickets. Barns also discovered that under-slept employees are more likely to blame other people in the workplace for their own mistakes, and even try to take credit for other people’s successful work: hardly a recipe for team building and a harmonious business environment.

Ethical deviance linked to a lack of sleep also weasels its way onto the work stage in a different guise, called social loafing. The term refers to someone who, when group performance is being assessed, decides to exert less effort when working in that group than when working alone. Individuals see an opportunity to slack off and hide behind the collective hard work of others. They complete fewer aspects of the task themselves, and that work tends to be either wrong or of lower quality, relative to when they alone are being assessed. Sleepy employees therefore choose the more selfish path of least resistance when working in teams, coasting by on the disingenuous ticket of social loafing.VI Not only does this lead to lower group productivity, understandably it often creates feelings of resentment and interpersonal aggression among team members.

Of note to those in business, many of these studies report deleterious effects on business outcomes on the basis of only very modest reductions in sleep amount within an individual, perhaps twenty- to sixty-minute differences between an employee who is honest, creative, innovate, collaborative, and productive and one who is not.

Examine the effects of sleep deficiency in CEOs and supervisors, and the story is equally impactful. An ineffective leader within any organization can have manifold trickle-down consequences to the many whom they influence. We often think that a good or bad leader is good or bad day after day—a stable trait. Not true. Differences in individual leadership performance fluctuate dramatically from one day to the next, and the size of that difference far exceeds the average difference from one individual leader to another. So what explains the ups and downs of a leader’s ability to effectively lead, day to day? The amount of sleep they are getting is one clear factor.

A deceptively simple but clever study tracked the sleep of supervisors across several weeks, and compared that with their leadership performance in the workplace as judged by the employees who report to them. (I should note that employees themselves had no knowledge of how well their boss was sleeping each night, taking away any knowledge bias.) The lower the quality of sleep that the supervisor reported getting from one night to the next accurately predicted poor self-control and a more abusive nature toward employees the following day, as reported by the employees themselves.

There was another equally intriguing result: in the days after a supervisor had slept poorly, the employees themselves, even if well rested, became less engaged in their jobs throughout that day as a consequence. It was a chain-reaction effect, one in which the lack of sleep in that one superordinate person in a business structure was transmitted on like a virus, infecting even well-rested employees with work disengagement and reduced productivity.

Reinforcing this reciprocity, we have since discovered that under-slept managers and CEOs are less charismatic and have a harder time infusing their subordinate teams with inspiration and drive. Unfortunately for bosses, a sleep-deprived employee will erroneously perceive a well-rested leader as being significantly less inspiring and charismatic than they truly are. One can only imagine the multiplicative consequences to the success of a business if both the leader and the employees are overworked and under-slept.

Allowing and encouraging employees, supervisors, and executives to arrive at work well rested turns them from simply looking busy yet ineffective, to being productive, honest, useful individuals who inspire, support, and help each other. Ounces of sleep offer pounds of business in return.

Employees also win financially when sleep times increase. Those who sleep more earn more money, on average, as economists Matthew Gibson and Jeffrey Shrader discovered when analyzing workers and their pay across the United States. They examined townships of very similar socioeducational and professional standing within the same time zone, but at very far western and eastern edges of these zones that receive significantly different amounts of daylight hours. Workers in the far western locations obtained more sunlight later into the evening, and consequently went to bed an hour later, on average, than those in the far eastern locations. However, all workers in both regions had to wake up at the same time each morning, since they were all in the same time zone and on the same schedule. Therefore, western-dwelling workers in that time zone had less sleep opportunity time than the eastern-dwelling workers.

Factoring out many other potential factors and influences (e.g., regional affluence, house prices, cost of living, etc.), they found that an hour of extra sleep still returned significantly higher wages in those eastern locations, somewhere in the region of 4 to 5 percent. You may sniff at that return on the investment of sixty minutes of sleep, but it’s not trivial. The average pay raise in the US is around 2.6 percent. Most people are strongly motivated to get that raise, and are upset when they don’t. Imagine almost doubling that pay raise—not by working more hours, but by getting more sleep!

The fact of the matter is that most people will trade sleep for a higher salary. A recent study from Cornell University surveyed hundreds of US workers and gave them a choice between either (1) $80,000 a year, working normal work hours, and getting the chance for around eight hours of sleep, or (2) $140,000 a year, working consistent overtime shifts, and only getting six hours of sleep each night. Unfortunately, the majority of individuals went with the second option of a higher salary and shorter sleep. That’s ironic, considering that you can have both, as we have discovered above.

The loud-and-proud corporate mentality of sleeplessness as the model for success is evidentially wrong at every level of analysis we have explored. Sound sleep is clearly sound business. Nevertheless, many companies remain deliberately antisleep in their structured practices. Like flies set in amber, this attitude keeps their businesses in a similarly frozen state of stagnation, lacking in innovation and productivity, and breeding employee unhappiness, dissatisfaction, and ill health.

There are, however, an increasing number of forward-looking companies who have changed their work practices in response to these research findings, and even welcome scientists like me into their businesses to teach and extol the virtues of getting more sleep to senior leaders and management. Procter & Gamble Co. and Goldman Sachs Group Inc., for example, both offer free “sleep hygiene” courses to their employees. Expensive, high-grade lighting has been installed in some of their buildings to better help workers regulate their circadian rhythms, improving the timed release of melatonin.

Nike and Google have both adopted a more relaxed approach to work schedules, allowing employees to time their daily work hours to match their individual circadian rhythms and their respective owl and lark chronotype nature. The change in mind-set is so radical that these same brand-leading corporations even allow workers to sleep on the job. Littered throughout their corporate headquarters are dedicated relaxation rooms with “nap pods.” Employees can indulge in sleep throughout the workday in these “shh” zones, germinating productivity and creativity while enhancing wellness and reducing absenteeism.

Such changes reflect a marked departure from the draconian days when any employee found catnapping on the clock was chastised, disciplined, or outright fired. Sadly, most CEOs and managers still reject the importance of a well-slept employee. They believe such accommodations represent the “soft approach.” But make no mistake: companies like Nike and Google are as shrewd as they are profitable. They embrace sleep due to its proven dollar value.

One organization above all has known about the occupational benefits of sleep longer than most. In the mid-1990s, NASA refined the science of sleeping on the job for the benefit of their astronauts. They discovered that naps as short as twenty-six minutes in length still offered a 34 percent improvement in task performance and more than a 50 percent increase in overall alertness. These results hatched the so-called NASA nap culture throughout terrestrial workers in the organization.

By any metrics we use to determine business success—profit margins, marketplace dominance/prominence, efficiency, employee creativity, or worker satisfaction and wellness—creating the necessary conditions for employees to obtain enough sleep at night, or in the workplace during the day, should be thought of as a new form of physiologically injected venture capital.

THE INHUMANE USE OF SLEEP LOSS IN SOCIETY

Business is not the only place where sleep deprivation and ethics collide. Governments and militaries bare a more disgraceful blemish.

Aghast at the mental and physical harm caused by prolonged sleep deprivation, in the 1980s Guinness ceased to recognize any attempts to break the world record for sleep deprivation. It even began deleting sleep deprivation records from their prior annals for fear that they would encourage future acts of deliberate sleep abstinence. It is for similar reasons that scientists have limited evidence of the long-term effects of total sleep deprivation (beyond a night or two). We feel it morally unacceptable to impose that state on humans—and increasingly, on any species.

Some governments do not share these same moral values. They will sleep deprive individuals against their will under the auspice of torture. This ethically and politically treacherous landscape may seem like an odd topic to include in this book. But I address it because it powerfully illuminates how humanity must reevaluate its views on sleep at the highest level of societal structure—that of government—and because it provides a clear example of how we can sculpt an increasingly admirable civilization by respecting, rather than abusing, sleep.

A 2007 report entitled “Leave No Marks: Enhanced Interrogation Techniques and the Risk of Criminality” offers a disquieting account of such practices in the modern day. The document was compiled by Physicians for Human Rights, an advocacy group seeking to end human torture. Telegraphed by the report’s title, many modern-day torture methods are deviously designed to leave no evidence of physical assault. Sleep deprivation epitomizes this goal and, at the time of writing this book, is still used for interrogation by countries, including Myanmar, Iran, Iraq, the United States, Israel, Egypt, Libya, Pakistan, Saudi Arabia, Tunisia, and Turkey.

As a scientist intimate with the workings of sleep, I would argue strongly for the abolition of this practice, structured around two clear facts. The first, and less important, is simply on grounds of pragmatism. In the context of interrogation, sleep deprivation is ill designed for the purpose of obtaining accurate, and thus actionable, intelligence. A lack of sleep, even moderate amounts, degrades every mental faculty necessary to obtain valid information, as we have seen. This includes the loss of accurate memory recall, emotional instability that prevents logical thought, and even basic verbal comprehension. Worse still, sleep deprivation increases deviant behavior and causes higher rates of lying and dishonesty.VII Short of coma, sleep deprivation places an individual into the least useful brain state for the purpose of credible intelligence gathering: a disordered mind from which false confessions will flourish—which, of course, could be the intent of some captors. Proof comes from a recent scientific study demonstrating that one night of sleep deprivation will double or even quadruple the likelihood that an otherwise upstanding individual will falsely confess to something they have not done. You can, therefore, change someone’s very attitudes, their behavior, and even their strongly held beliefs simply by taking sleep away from them.

An eloquent yet distressing affirmation of this fact is provided by the former prime minister of Israel, Menachem Begin, in his autobiography, White Nights: The Story of a Prisoner in Russia. In the 1940s, years before taking office in 1977, Begin was captured by the Soviets. He was tortured in prison by the KGB, one component of which involved prolonged sleep deprivation. Of this experience (which most governments benignly describe as the practice of “prisoner sleep management”), he writes:

In the head of the interrogated prisoner a haze begins to form. His spirit is wearied to death, his legs are unsteady, and he has one sole desire: to sleep, to sleep just a little, not to get up, to lie, to rest, to forget . . . Anyone who has experienced this desire knows that not even hunger or thirst are comparable with it . . . I came across prisoners who signed what they were ordered to sign, only to get what their interrogator promised them. He did not promise them their liberty. He promised them—if they signed—uninterrupted sleep.

The second and more forceful argument for the abolition of enforced sleep deprivation is the permanent physical and mental harm it inflicts. Unfortunately, though conveniently for interrogators, the harm inflicted is not obvious from the outside. Mentally, long-term sleep deprivation over many days elevates suicidal thoughts and suicide attempts, both of which occur at vastly higher rates in detained prisoners relative to the general population. Inadequate sleep further cultivates the disabling and non-transient conditions of depression and anxiety. Physically, prolonged sleep deprivation increases the likelihood of a cardiovascular event, such as a heart attack or stroke, weakens the immune system in ways that encourage cancer and infection, and renders genitals infertile.

Several US federal courts hold a similarly damning view of these practices, ruling that sleep deprivation violates both the Eighth and Fourteenth Amendments of the United States Constitution regarding protection from cruel and inhuman punishment. Their rationale was sound and impenetrable: “sleep,” it was stated, must be considered a “basic life necessity,” which it clearly is.

Nevertheless, the US Department of Defense subverted this ruling, authorizing twenty-hour interrogations of detainees in Guantánamo Bay between 2003 and 2004. Such treatment remains permissible to this day of writing, as the revised US Army Field Manual states, in appendix M, that detainees can be limited to just four hours of sleep every twenty-four hours, for up to four weeks. I note that it was not always so. A much earlier 1992 edition of the same publication held that extended sleep deprivation was a clear and inhumane example of “mental torture.”

Depriving a human of sleep without their willing consent and careful medical care is a barbaric tool of assault, psychologically and biologically. Measured on the basis of mortality impact over the long term, it is on a par with starvation. It is high time to close the chapter on torture, including the use of sleep deprivation—an unacceptable and inhumane practice, one that I believe we will look back on with the very deepest of shame in years to come.

SLEEP AND EDUCATION

More than 80 percent of public high schools in the United States begin before 8:15 a.m. Almost 50 percent of those start before 7:20 a.m. School buses for a 7:20 a.m. start time usually begin picking up kids at around 5:45 a.m. As a result, some children and teenagers must wake up at 5:30 a.m., 5:15 a.m., or even earlier, and do so five days out of every seven, for years on end. This is lunacy.

Could you concentrate and learn much of anything when you had woken up so early? Keep in mind that 5:15 a.m. to a teenager is not the same as 5:15 a.m. to an adult. Previously, we noted that the circadian rhythm of teenagers shifts forward dramatically by one to three hours. So really the question I should ask you, if you are an adult, is this: Could you concentrate and learn anything after having forcefully been woken up at 3:15 a.m., day after day after day? Would you be in a cheerful mood? Would you find it easy to get along with your coworkers and conduct yourself with grace, tolerance, respect, and a pleasant demeanor? Of course not. Why, then, do we ask this of the millions of teenagers and children in industrialized nations? Surely this is not an optimal design of education. Nor does it bear any resemblance to a model for nurturing good physical or mental health in our children and teenagers.

Forced by the hand of early school start times, this state of chronic sleep deprivation is especially concerning considering that adolescence is the most susceptible phase of life for developing chronic mental illnesses, such as depression, anxiety, schizophrenia, and suicidality. Unnecessarily bankrupting the sleep of a teenager could make all the difference in the precarious tipping point between psychological wellness and lifelong psychiatric illness. This is a strong statement, and I do not write it flippantly or without evidence. Back in the 1960s, when the functions of sleep were still largely unknown, researchers selectively deprived young adults of REM sleep, and thus dreaming, for a week, while still allowing them NREM sleep.

The unfortunate study participants spent the entire time in the laboratory with electrodes placed on their heads. At night, whenever they entered into the REM-sleep state, a research assistant would quickly enter the bedroom and wake the subjects up. The blurry-eyed participants then had to do math problems for five to ten minutes, preventing them from falling back into dream sleep. But as soon as the participants did return into REM sleep, the procedure was repeated. Hour after hour, night after night, this went on for an entire week. NREM sleep was left largely intact, but the amount of REM sleep was reduced to a fraction of its regular quantity.

It didn’t require all seven nights of dream-sleep deprivation before the mental health effects began to manifest. By the third day, participants were expressing signs of psychosis. They became anxious, moody, and started to hallucinate. They were hearing things and seeing things that were not real. They also became paranoid. Some believed that the researchers were plotting against them in collusive ways—trying to poison them, for example. Others became convinced that the scientists were secret agents, and that the experiment was a thinly veiled government conspiracy of some wicked kind.

Only then did scientists realize the rather profound conclusions of the experiment: REM sleep is what stands between rationality and insanity. Describe these symptoms to a psychiatrist without informing them of the REM-sleep deprivation context, and the clinician will give clear diagnoses of depression, anxiety disorders, and schizophrenia. But these were all healthy young individuals just days before. They were not depressed, weren’t suffering from anxiety disorders or schizophrenia, nor did they have any history of such conditions, self or familial. Read of any attempts to break sleep-deprivation world records throughout early history, and you will discover this same universal signature of emotional instability and psychosis of one sort or another. It is the lack of REM sleep—that critical stage occurring in the final hours of sleep that we strip from our children and teenagers by way of early school start times—that creates the difference between a stable and unstable mental state.

Our children didn’t always go to school at this biologically unreasonable time. A century ago, schools in the US started at nine a.m. As a result, 95 percent of all children woke up without an alarm clock. Now, the inverse is true, caused by the incessant marching back of school start times—which are in direct conflict with children’s evolutionarily preprogrammed need to be asleep during these precious, REM-sleep-rich morning hours.

The Stanford psychologist Dr. Lewis Terman, famous for helping construct the IQ test, dedicated his research career to the betterment of children’s education. Starting in the 1920s, Terman charted all manner of factors that promoted a child’s intellectual success. One such factor he discovered was sufficient sleep. Published in his seminal papers and book Genetic Studies of Genius, Terman found that no matter what the age, the longer a child slept, the more intellectually gifted they were. He further found that sleep time was most strongly connected to a reasonable (i.e., a later) school start time: one that was in harmony with the innate biological rhythms of these young, still-maturing brains.

While cause and effect cannot be resolved in Terman’s studies, the data convinced him that sleep was a matter for strong public advocacy when it comes to a child’s schooling and healthy development. As president of the American Psychological Association, he warned with great emphasis that the United States must never follow a trend that was emerging in some European countries, where school start times were creeping ever earlier, starting at eight a.m. or even seven a.m., rather than at nine a.m.

Terman believed that this swing to an early-morning model of education would damage, and damage deeply, the intellectual growth of our youth. Despite his warnings, nearly a hundred years later, US education systems have shifted to early school start times, while many European countries have done just the opposite.

We now have the scientific evidence that supports Terman’s sage wisdom. One longitudinal study tracked more than 5,000 Japanese schoolchildren and discovered that those individuals who were sleeping longer obtained better grades across the board. Controlled sleep laboratory studies in smaller samples show that children with longer total sleep times develop superior IQ, with brighter children having consistently slept forty to fifty minutes more than those who went on to develop a lower IQ.

Examinations of identical twins further impress how powerful sleep is as a factor that can alter genetic determinism. In a study that was started by Dr. Ronald Wilson at Louisville School of Medicine in the 1980s, which continues to this day, hundreds of twin pairs were assessed at a very young age. The researchers specifically focused on those twins in which one was routinely obtaining less sleep than the other, and tracked their developmental progress over the following decades. By ten years of age, the twin with the longer sleep pattern was superior in their intellectual and educational abilities, with higher scores on standardized tests of reading and comprehension, and a more expansive vocabulary than the twin who was obtaining less sleep.

Such associational evidence is not proof that sleep is causing such powerful educational benefits. Nevertheless, combined with causal evidence linking sleep to memory that we have covered in chapter 6, a prediction can be made: if sleep really is so rudimentary to learning, then increasing sleep time by delaying start times should prove transformative. It has.

A growing number of schools in the US have started to revolt against the early start time model, beginning the school day at somewhat more biologically reasonable times. One of the first test cases happened in the township of Edina, Minnesota. Here, school start times for teenagers were shifted from 7:25 a.m. to 8:30 a.m. More striking than the forty-three minutes of extra sleep that these teens reported getting was the change in academic performance, indexed using a standardized measure called the Scholastic Assessment Test, or SAT.

In the year before this time change, the average verbal SAT scores of the top-performing students was a very respectable 605. The following year, after switching to an 8:30 a.m. start time, that score rose to an average 761 for the same top-tier bracket of students. Math SAT scores also improved, increasing from an average of 683 in the year prior to the time change, to 739 in the year after. Add this all up, and you see that investing in delaying school start times—allowing students more sleep and better alignment with their unchangeable biological rhythms—returned a net SAT profit of 212 points. That improvement will change which tier of university those teenagers go to, potentially altering their subsequent life trajectories as a consequence.

While some have contested how accurate or sound the Edina test case is, well-controlled and far larger systematic studies have proved that Edina is no fluke. Numerous counties in several US states have shifted the start of schools to a later hour and their students experienced significantly higher grade point averages. Unsurprisingly, performance improvements were observed regardless of time of day; however, the most dramatic surges occurred in morning classes.

It is clear that a tired, under-slept brain is little more than a leaky memory sieve, in no state to receive, absorb, or efficiently retain an education. To persist in this way is to handicap our children with partial amnesia. Forcing youthful brains to become early birds will guarantee that they do not catch the worm, if the worm in question is knowledge or good grades. We are, therefore, creating a generation of disadvantaged children, hamstrung by a privation of sleep. Later school start times are clearly, and literally, the smart choice.

One of the most troubling trends emerging in this area of sleep and brain development concerns low-income families—a trend that has direct relevance to education. Children from lower socioeconomic backgrounds are less likely to be taken to school in a car, in part because their parents often have jobs in the service industry demanding work start times at or before six a.m. Such children therefore rely on school buses for transit, and must wake up earlier than those taken to school by their parents. As a result, those already disadvantaged children become even more so because they routinely obtain less sleep than children from more affluent families. The upshot is a vicious cycle that perpetuates from one generation to the next—a closed-loop system that is very difficult to break out of. We desperately need active intervention methods to shatter this cycle, and soon.

Research findings have also revealed that increasing sleep by way of delayed school start times wonderfully increases class attendance, reduces behavioral and psychological problems, and decreases substance and alcohol use. In addition, later start times beneficially mean a later finish time. This protects many teens from the well-researched “danger window” between three and six p.m., when schools finish but before parents return home. This unsupervised, vulnerable time period is a recognized cause of involvement in crime and alcohol and substance abuse. Later school start times profitably shorten this danger window, reduce these adverse outcomes, and therefore lower the associated financial cost to society (a savings that could be reinvested to offset any additional expenditures that later school start times require).

Yet something even more profound has happened in this ongoing story of later school start times—something that researchers did not anticipate: the life expectancy of students increased. The leading cause of death among teenagers is road traffic accidents,VIII and in this regard, even the slightest dose of insufficient sleep can have marked consequences, as we have discussed. When the Mahtomedi School District of Minnesota pushed their school start time from 7:30 to 8:00 a.m., there was a 60 percent reduction in traffic accidents in drivers sixteen to eighteen years of age. Teton County in Wyoming enacted an even more dramatic change in school start time, shifting from a 7:35 a.m. bell to a far more biologically reasonable one of 8:55 a.m. The result was astonishing—a 70 percent reduction in traffic accidents in sixteen- to eighteen-year-old drivers.

To place that in context, the advent of anti-lock brake technology (ABS)—which prevents the wheels of a car from seizing up under hard braking, allowing the driver to still maneuver the vehicle—reduced accident rates by around 20 to 25 percent. It was deemed a revolution. Here is a simple biological factor—sufficient sleep—that will drop accident rates by more than double that amount in our teens.

These publicly available findings should have swept the education system in an uncompromising revision of school start times. Instead, they have largely been swept under the rug. Despite public appeals from the American Academy of Pediatrics and the Centers for Disease Control and Prevention, change has been slow and hard-fought. It is not enough.

School bus schedules and bus unions are a major roadblock thwarting appropriately later school start times, as is the established routine of getting the kids out the door early in the morning so that parents can start work early. These are good reasons for why shifting to a national model of later school start times is difficult. They are real pragmatic challenges that I truly appreciate, and sympathize with. But I don’t feel they are sufficient excuses for why an antiquated and damaging model should remain in place when the data are so clearly unfavorable. If the goal of education is to educate, and not risk lives in the process, then we are failing our children in the most spectacular manner with the current model of early school start times.

Without change, we will simply perpetuate a vicious cycle wherein each generation of our children are stumbling through the education system in a half-comatose state, chronically sleep-deprived for years on end, stunted in their mental and physical growth as a consequence, and failing to maximize their true success potential, only to inflict that same assault on their own children decades later. This harmful spiral is only getting worse. Data aggregated over the past century from more than 750,000 schoolchildren aged five to eighteen reveal that they are sleeping two hours fewer per night than their counterparts were a hundred years ago. This is true no matter what age group, or sub-age group, you consider.

An added reason for making sleep a top priority in the education and lives of our children concerns the link between sleep deficiency and the epidemic of ADHD (attention deficit hyperactivity disorder). Children with this diagnosis are irritable, moodier, more distractible and unfocused in learning during the day, and have a significantly increased prevalence of depression and suicidal ideation. If you make a composite of these symptoms (unable to maintain focus and attention, deficient learning, behaviorally difficult, with mental health instability), and then strip away the label of ADHD, these symptoms are nearly identical to those caused by a lack of sleep. Take an under-slept child to a doctor and describe these symptoms without mentioning the lack of sleep, which is not uncommon, and what would you imagine the doctor is diagnosing the child with, and medicating them for? Not deficient sleep, but ADHD.

There is more irony here than meets the eye. Most people know the name of the common ADHD medications: Adderall and Ritalin. But few know what these drugs actually are. Adderall is amphetamine with certain salts mixed in, and Ritalin is a similar stimulant, called methylphenidate. Amphetamine and methylphenidate are two of the most powerful drugs we know of to prevent sleep and keep the brain of an adult (or a child, in this case) wide awake. That is the very last thing that such a child needs. As my colleague in the field, Dr. Charles Czeisler, has noted, there are people sitting in prison cells, and have been for decades, because they were caught selling amphetamines to minors on the street. However, we seem to have no problem at all in allowing pharmaceutical companies to broadcast prime-time commercials highlighting ADHD and promoting the sale of amphetamine-based drugs (e.g., Adderall, Ritalin). To a cynic, this seems like little more than an uptown version of a downtown drug pusher.

I am in no way contesting the disorder of ADHD, and not every child with ADHD has poor sleep. But we know that there are children, many children, perhaps, who are sleep-deprived or suffering from an undiagnosed sleep disorder that masquerades as ADHD. They are being dosed for years of their critical development with amphetamine-based drugs.

One example of an undiagnosed sleep disorder is pediatric sleep-disordered breathing, or child obstructive sleep apnea, which is associated with heavy snoring. Overly large adenoids and tonsils can block the airway passage of a child as their breathing muscles relax during sleep. The labored snoring is the sound of turbulent air trying to be sucked down into the lungs through a semi-collapsed, fluttering airway. The resulting oxygen debt will reflexively force the brain to awaken the child briefly throughout the night so that several full breaths can be obtained, restoring full blood oxygen saturation. However, this prevents the child from reaching and/or sustaining long periods of valuable deep NREM sleep. Their sleep-disordered breathing will impose a state of chronic sleep deprivation, night after night, for months or years on end.

As the state of chronic sleep deprivation builds over time, the child will look ever more ADHD-like in temperament, cognitively, emotionally, and academically. Those children who are fortunate to have the sleep disorder recognized, and who have their tonsils removed, more often than not prove that they do not have ADHD. In the weeks after the operation, a child’s sleep recovers, and with it, normative psychological and mental functioning in the months ahead. Their “ADHD” is cured. Based on recent surveys and clinical evaluations, we estimate that more than 50 percent of all children with an ADHD diagnosis actually have a sleep disorder, yet a small fraction know of their sleep condition and its ramifications. A major public health awareness campaign by governments—perhaps without influence from pharmaceutical lobbying groups—is needed on this issue.

Stepping back from the issue of ADHD, the bigger-picture problem is ever clearer. Failed by the lack of any governmental guidelines and poor communication by researchers such as myself regarding the extant scientific data, many parents remain oblivious to the state of childhood sleep deprivation, so often undervaluing this biological necessity. A recent poll by the National Sleep Foundation affirms this point, with well over 70 percent of parents believing their child gets enough sleep, when in reality, less than 25 percent of children aged eleven to eighteen actually obtain the necessary amount.

As parents, we therefore have a jaundiced view of the need and importance of sleep in our children, sometimes even chastising or stigmatizing their desire to sleep enough, including their desperate weekend attempts to repay a sleep debt that the school system has saddled them with through no fault of their own. I hope we can change. I hope we can break the parent-to-child transmission of sleep neglect and remove what the exhausted, fatigued brains our youth are so painfully starved of. When sleep is abundant, minds flourish. When it is deficient, they don’t.

SLEEP AND HEALTH CARE

If you are about to receive medical treatment at a hospital, you’d be well advised to ask the doctor: “How much sleep have you had in the past twenty-four hours?” The doctor’s response will determine, to a statistically provable degree, whether the treatment you receive will result in a serious medical error, or even death.

All of us know that nurses and doctors work long, consecutive hours, and none more so than doctors during their resident training years. Few people, however, know why. Why did we ever force doctors to learn their profession in this exhausting, sleepless way? The answer originates with the esteemed physician William Stewart Halsted, MD, who was also a helpless drug addict.

Halsted founded the surgical training program at Johns Hopkins Hospital in Baltimore, Maryland, in May 1889. As chief of the Department of Surgery, his influence was considerable, and his beliefs about how young doctors must apply themselves to medicine, formidable. There was to be a six-year residency, quite literally. The term “residency” came from Halsted’s belief that doctors must live in the hospital for much of their training, allowing them to be truly committed in their learning of surgical skills and medical knowledge. Fledgling residents had to suffer long, consecutive work shifts, day and night. To Halsted, sleep was a dispensable luxury that detracted from the ability to work and learn. Halsted’s mentality was difficult to argue with, since he himself practiced what he preached, being renowned for a seemingly superhuman ability to stay awake for apparently days on end without any fatigue.

But Halsted had a dirty secret that only came to light years after his death, and helped explain both the maniacal structure of his residency program and his ability to forgo sleep. Halsted was a cocaine addict. It was a sad and apparently accidental habit, one that started years before his arrival at Johns Hopkins.

Early in his career, Halsted was conducting research on the nerve-blocking abilities of drugs that could be used as anesthetics to dull pain in surgical procedures. One of those drugs was cocaine, which prevents electrical impulse waves from shooting down the length of the nerves in the body, including those that transmit pain. Addicts of the drug know this all too well, as their nose, and often their entire face, will become numb after snorting several lines of the substance, almost like having been injected with too much anesthetic by an overly enthusiastic dentist.

Working with cocaine in the laboratory, it didn’t take long before Halsted was experimenting on himself, after which the drug gripped him in an ceaseless addiction. If you read Halsted’s academic report of his research findings in the New York Medical Journal from September 12, 1885, you’d be hard pressed to comprehend it. Several medical historians have suggested that the writing is so discombobulated and frenetic that he undoubtedly wrote the piece when high on cocaine.

Colleagues noticed Halsted’s odd and disturbing behaviors in the years before and after his arrival at Johns Hopkins. This included excusing himself from the operating theater while he was supervising residents during surgical procedures, leaving the young doctors to complete the operation on their own. At other times, Halsted was not able to operate himself because his hands were shaking so much, the cause of which he tried to pass off as a cigarette addiction.

Halsted was now in dire need of help. Ashamed and nervous that his colleagues would discover the truth, he entered a rehabilitation clinic under his first and middle name, rather than using his surname. It was the first of many unsuccessful attempts at kicking his habit. For one stay at Butler Psychiatric Hospital in Providence, Rhode Island, Halsted was given a rehabilitation program of exercise, a healthy diet, fresh air, and, to help with the pain and discomfort of cocaine withdrawal, morphine. Halsted subsequently emerged from the “rehabilitation” program with both a cocaine addiction and a morphine addiction. There were even stories that Halsted would inexplicably send his shirts to be laundered in Paris, and they would return in a parcel containing more than just pure-white shirts.

Halsted inserted his cocaine-infused wakefulness into the heart of Johns Hopkins’s surgical program, imposing a similarly unrealistic mentality of sleeplessness upon his residents for the duration of their training. The exhausting residency program, which persists in one form or another throughout all US medical schools to this day, has left countless patients hurt or dead in its wake—and likely residents, too. That may sound like an unfair charge to level considering the wonderful, lifesaving work our committed and caring young doctors and medical staff perform, but it is a provable one.

Many medical schools used to require residents to work thirty hours. You may think that’s short, since I’m sure you work at least forty hours a week. But for residents, that was thirty hours all in one go. Worse, they often had to do two of these thirty-hour continuous shifts within a week, combined with several twelve-hour shifts scattered in between.

The injurious consequences are well documented. Residents working a thirty-hour-straight shift will commit 36 percent more serious medical errors, such as prescribing the wrong dose of a drug or leaving a surgical implement inside of a patient, compared with those working sixteen hours or less. Additionally, after a thirty-hour shift without sleep, residents make a whopping 460 percent more diagnostic mistakes in the intensive care unit than when well rested after enough sleep. Throughout the course of their residency, one in five medical residents will make a sleepless-related medical error that causes significant, liable harm to a patient. One in twenty residents will kill a patient due to a lack of sleep. Since there are over 100,000 residents currently in training in US medical programs, this means that many hundreds of people—sons, daughters, husbands, wives, grandparents, brothers, sisters—are needlessly losing their lives every year because residents are not allowed to get the sleep they need. As I write this chapter, a new report has discovered that medical errors are the third-leading cause of death among Americans after heart attacks and cancer. Sleeplessness undoubtedly plays a role in those lives lost.

Young doctors themselves can become part of the mortality statistics. After a thirty-hour continuous shift, exhausted residents are 73 percent more likely to stab themselves with a hypodermic needle or cut themselves with a scalpel, risking a blood-born infectious disease, compared to their careful actions when adequately rested.

One of the most ironic statistics concerns drowsy driving. When a sleep-deprived resident finishes a long shift, such as a stint in the ER trying to save victims of car accidents, and then gets into their own car to drive home, their chances of being involved in a motor vehicle accident are increased by 168 percent because of fatigue. As a result, they may find themselves back in the very same hospital and ER from which they departed, but now as a victim of a car crash caused by a microsleep.

Senior medical professors and attending physicians suffer the same bankruptcy of their medical skills following too little sleep. For example, if you are a patient under the knife of an attending physician who has not been allowed at least a six-hour sleep opportunity the night prior, there is a 170 percent increased risk of that surgeon inflicting a serious surgical error on you, such as organ damage or major hemorrhaging, relative to the superior procedure they would conduct when they have slept adequately.

If you are about to undergo an elective surgery, you should ask how much sleep your doctor has had and, if it is not to your liking, you may not want to proceed. No amount of years on the job helps a doctor “learn” how to overcome a lack of sleep and develop resilience. How could it? Mother Nature spent millions of years implementing this essential physiological need. To think that bravado, willpower, or a few decades of experience can absolve you (a surgeon) of an evolutionarily ancient necessity is the type of hubris that, as we know from the evidence, costs lives.

The next time you see a doctor in a hospital, keep in mind the study we have previously discussed, showing that after twenty-two hours without sleep, human performance is impaired to the same level as that of someone who is legally drunk. Would you ever accept hospital treatment from a doctor who pulled out a hip flask of whiskey in front of you, took a few swigs, and proceeded with an attempt at medical care in a vague stupor? Neither would I. Why, then, should society be facing an equally irresponsible health-care roulette game in the context of sleep deprivation?

Why haven’t these, and now many similar such findings, triggered a responsible revision of work schedules for residents and attending physicians by the American medical establishment? Why are we not giving back sleep to our exhausted and thus error-prone doctors? The collective goal is, after all, to achieve the highest quality of medical practice and care, is it not?

Facing government threats that would apply federally enforced work hours due to the extent of damning evidence, the Accreditation Council for Graduate Medical Education made the following alterations. First-year residents would be limited to (1) working no more than an 80-hour week (which still averages out at 11.5 hours per day for 7 days straight), (2) working no more than 24 hours nonstop, and (3) performing one overnight on-call shift every third night. That revised schedule still far exceeds any ability of the brain to perform optimally. Errors, mistakes, and deaths continued in response to the anemic diet of sleep they were being fed while training. As the research studies kept accumulating, the Institute of Medicine, part of the US National Academy of Sciences, issued a report with a clear statement: working for more than sixteen consecutive hours without sleep is hazardous for both the patient and resident physician.

You may have noticed my specific wording in the above paragraph: first-year residents. This is because the revised rule (at the time of writing this book) has only been applied to those in their first year of training, and not to those in later years of a medical residency. Why? Because the Accreditation Council for Graduate Medical Education—the elite board of high-powered physicians that dictates the American residency training structure—stated that data proving the dangers of insufficient sleep had only been gathered in residents in their first year of the program. As a result, they felt there was no evidence to justify a change for residents in years two to five—as if getting past the twelve-month point in a medical residency program magically confers immunity against the biological and psychological effects of sleep deprivation—effects that these same individuals had previously been so provably vulnerable to just months before.

This entrenched pomposity, prevalent in so many senior-driven, dogmatic institutional hierarchies, has no place in medical practice in my opinion as a scientist intimate with the research data. Those boards must disabuse themselves of the we-suffered-through-sleep-deprivation-and-you-should-too mentality when it comes to training, teaching, and practicing medicine.

Of course, medical institutions put forward other arguments to justify the old-school way of sleep abuse. The most common harkens back to a William Halsted–like mind-set: without working exhaustive shifts, it will take far too long to train residents, and they will not learn as effectively. Why, then, can several western European countries train their young doctors within the same time frame when they are limited to working no more than forty-eight hours in one week, without continuous long periods of sleeplessness? Perhaps they are just not as well trained? This, too, is erroneous, since many of those western European medical programs, such as in the UK and Sweden, rank among the top ten countries for most medical practice health outcomes, while the majority of US institutes rank somewhere between eighteenth and thirty-second. As a matter of fact, several pilot studies in the US have shown that when you limit residents to no more than a sixteen-hour shift, with at least an eight-hour rest opportunity before the next shift,IX the number of serious medical errors made—defined as causing or having the potential to cause harm to a patient—drops by over 20 percent. Furthermore, residents made 400 to 600 percent fewer diagnostic errors to begin with.

There’s simply no evidence-based argument for persisting with the current sleep-anemic model of medical training, one that cripples the learning, health, and safety of young doctors and patients alike. That it remains this way in the stoic grip of senior medical officials appears to be a clear case of “my mind is made up, don’t confuse me with the facts.”

More generally, I feel we as a society must work toward dismantling our negative and counterproductive attitude toward sleep: one that is epitomized in the words of a US senator who once said, “I’ve always loathed the necessity of sleep. Like death, it puts even the most powerful men on their backs.” This attitude perfectly encapsulates many a modern view of sleep: loathsome, annoying, enfeebling. Though the senator in question is a television character called Frank Underwood from the series House of Cards, the writers have—biographically, I believe—placed their fingers on the very nub of the sleep-neglect problem.

Tragically, this same neglect has resulted in some of the worst global catastrophes punctuating the human historical record. Consider the infamous reactor meltdown at the Chernobyl nuclear power station on April 26, 1986. The radiation from the disaster was one hundred times more powerful than the atomic bombs dropped in World War II. It was the fault of sleep-deprived operators working an exhaustive shift, occurring, without coincidence, at one a.m. Thousands died from the long-term effects of radiation in the protracted decades following the event, and tens of thousands more suffered a lifetime of debilitating medical and developmental ill health. We can also recount the Exxon Valdez oil tanker that ran aground on Bligh Reef in Alaska on March 24, 1989, breaching its hull. An estimated 10 million to 40 million gallons of crude oil spilled across a 1,300-mile range of the surrounding shoreline. Left dead were more than 500,000 seabirds, 5,000 otters, 300 seals, over 200 bald eagles, and 20 orca whales. The coastal ecosystem has never recovered. Early reports suggested that the captain was inebriated while navigating the vessel. Later, however, it was revealed that the sober captain had turned over command to his third mate on deck, who had only slept six out of the previous forty-eight hours, causing him to make the cataclysmic navigational error.

Both of these global tragedies were entirely preventable. The same is true for every sleep-loss statistic in this chapter.