Dreamland: Adventures in the Strange Science of Sleep (10 page)

Subjects who were able to reach deeper stages of sleep demonstrated a better command of flexible thinking, a vital cognitive skill that allows us to apply old facts and information to new situations. Sleep can also help the brain to recognize patterns. In a study conducted by Simon Durrant, a professor at the University of Manchester in England, subjects listened to a short burst of melodic tones. Later, they were asked to recognize when this sequence played during a much longer stretch of music. As in the study by the New York researchers, subjects were divided between those who were able to take a nap and those who weren’t. The amount of time spent in deep, slow-wave sleep during the nap predicted a subject’s later performance. Those who reached deep sleep in the nap had a greater rate of improvement at the task of recognizing the abstract patterns in music than did those who simply stayed awake.

Subjects who have been allowed to take naps have finished mazes faster, have become less emotional when confronted with disturbing images, and have remembered a longer list of words than their peers who hadn’t been allowed to doze off. Scientists currently think that the process of clearing the mind of unnecessary information and honing skills is at work in all stages of sleep. The benefits improve exponentially the longer someone rests.

Naps are even being used to provide a competitive advantage in the workplace. Companies such as Google, Nike, Procter & Gamble, and Cisco Systems have installed designated napping areas in their offices. The idea is that naps may allow engineers and designers to arrive at creative solutions more quickly than they would by staying awake all day. Consultants from companies with names like Alertness Solutions charge thousands of dollars to educate corporate managers and their employees on the importance of sleep and managing fatigue levels while on the job. Only this time, it is not about worker safety. It’s about speeding up the process of manufacturing ideas.

There is one line of work where spending more time sleeping is now seen as a critical part of not only generating creative ideas but also saving lives. It only took a few accidents on the way to get there.

7

The Weapon “Z”

A
s the sun fell over the desert, the rumble of tanks slowed and then stopped. The men of the Second Armored Cavalry Regiment found themselves surrounded by a sea of sand. It was February 25, 1991, and about fifty hours into the Gulf War, or what would later be called the Hundred Hour War. In that short amount of time, an international coalition led by the United States had pushed the Iraqi Army out of Kuwait and had it on the run. Throughout the Arabian Desert, Iraqi forces found themselves stuck in slow, outdated tanks that Saddam Hussein had purchased from the Soviet Union. Not long after the sale, the Kremlin realized that the tanks had serious problems with firing accuracy and rushed to upgrade the Soviet fleet, but Saddam apparently hadn’t kept the receipt. Iraqis soon discovered another curious fault of Soviet engineering: when hit, the turrets of their tanks broke cleanly apart from the vehicle and shot into the air, a phenomenon that coalition forces dubbed the “pop-top.” All across the desert, the tops of Iraqi tanks lay smoldering in the sand.

After racing into southern Iraq, the Second Armored Cavalry was told to wait. Another coalition unit had pushed ahead of schedule, and plowing along with them meant there could be a chance of friendly fire. The tanks formed a literal line in the sand and waited in the dark desert night, battered by high winds and heavy rain. It was their first real break after days of combat. Over each of the last five nights, the men had slept less than three hours. Nevertheless, they stood fixed at their stations with night-vision goggles strapped to their heads, staring into the blankness surrounding them. At one in the morning, the first few blips of activity appeared in their sights. The Iraqi forces that unknowingly corresponded to those movements had no idea they were about to run into a row of armed Americans who had the ability to see in the dark. As soon as the U.S. forces confirmed that the vehicles ahead of them were the enemy, they reverted to the unambiguous motto of all tank crews in battle: if it’s ahead of us, it dies.

The night air echoed with the sound of gunfire. During the fight, three tanks on the far right side of the U.S. line were forced out of the pack. They took evasive maneuvers, turning left and right to regain an upper hand. Suddenly, the number of enemy forces seemed to triple. Stuck out of position, the American tanks fired round after round from their twenty-five-millimeter cannons. They destroyed the vehicles in front of them and survived without taking a hit. By the time the shooting stopped, the American forces had destroyed every Iraqi tank, but they had also lost two of their own.

Later, in the briefing room, military planners wondered how Iraqi forces were able to zero in on tanks that were faster, stronger, and equipped with better technology. Throughout the whole war, enemy forces would destroy only about two-dozen American vehicles. Yet here, in a small battle conducted entirely in the middle of a rainy night, there were two down. Was it bad luck? Or were some Iraqi forces equipped with a weapon that the U.S. military didn’t anticipate? A team went to examine the wreckage of the two doomed Bradleys and interviewed their crews, all of whom survived thanks to their fire-retardant suits, which could withstand temperatures up to two thousand degrees. Sifting through the burning metal, investigators soon held the answer: casings from antitank rounds that could have been fired only from a U.S. vehicle. The two tanks had been lost to friendly fire.

It was a scenario that kept playing out across the desert. In the Gulf War, one of every four American combat deaths was a result of fire from U.S. forces. Not long after the war ended, a team of U.S. Army psychologists began to investigate why soldiers kept attacking the wrong people. Like polio or smallpox, friendly fire should have been eradicated by technology and training. In the months leading up to the Gulf War, tank commanders had spent hundreds of hours in simulated battles. Crews inside each tank had laser-guided sensors that could identify a vehicle based on the heat it gave off, while soldiers on the ground carried six-pound packs containing receivers that grabbed information from orbiting satellites so they could pinpoint nearby coalition forces on a map. The fog of war, if not entirely dissipated, should have shown signs of burning off. But the rate of friendly-fire accidents wasn’t falling like it was supposed to.

Something was happening in the midst of battle that soldiers weren’t prepared for and that was leading to casualties. Researchers interviewed soldiers who shot at their own forces and those who were the targets. They pored over training manuals. They built intricate timelines, precise to the second, that detailed when the mistaken shots were fired and what was going through each soldier’s mind at the time. They compared real-world conditions with results gleamed from research studies, considering everything from reaction times to morale.

After all of their digging, one truth stared at them, a conclusion that was as obvious as it was radical: soldiers simply weren’t getting enough sleep. The skills and training built up over hundreds of hours of preparation were lost on the battlefield amid the sleep deprivation of combat. The effects of sleep deprivation were strong enough that they threatened to derail the greatest military organization in the world. The needs of the human body, and the vital role that sleep plays in how the brain makes rational decisions, were trumping the top-secret technology and hardware that should have given U.S. forces total dominance over their enemies.

Men and women in the military fly around the world and do everything but sleep. Their lives are set out to the minute. In combat zones, most soldiers have no say in when they wake up, when they eat breakfast, or when they lie down at night. In peacetime, soldiers will be lucky if they get six hours of rest a night, or about three-quarters of what most adult bodies need to maintain an alert brain. Adolescent bodies—including the thousands of young recruits who are still not old enough to drink legally—often need nine hours of sleep to be fully restored.

Without deep sleep, the brain morphs from being our greatest evolutionary asset to our greatest weakness. During a study of crew members on a U.S. Coast Guard ship traveling from Virginia to Nova Scotia, for instance, researchers found that twelve of fourteen sailors fell asleep at their posts at least once. It would be impossible to put a dollar cost on all of the bad decisions resulting from the hours of lost sleep, but here is one small but telling number: in 1996, a time of relative peace, crew fatigue was blamed for thirty-two accidents that destroyed American military aircraft, including three F-14 jetfighters that cost $38 million each.

Twelve years after the Gulf War, American tanks once again rumbled through the desert of southern Iraq, this time with the purpose of going all the way to Baghdad. War planners had taken into account how much fuel, food, and ammunition each unit would need for Operation Iraqi Freedom to succeed. Sleep, however, wasn’t considered a necessity. The result was an army full of soldiers who had slept only two hours a night during the countdown to war. The dash north from the border of Kuwait stalled several times when drivers behind the wheels of tanks and Humvees fell asleep and veered off the side of the road. The lack of sleep “is our biggest enemy,” one marine colonel said during a break in combat. “It makes easy tasks difficult.”

Officers in combat nevertheless pushed their soldiers to go without sleep, willfully trading the tactical advantages of speed and mobility for the drawbacks built up from fatigue. Sleep deprivation increased up the chain of command. Many officers stayed awake for more than forty-eight hours straight during the first stage of combat, and when they did sleep, they would lie down for only twenty-minute naps at a time. One commander said that he was able to function after sleeping a total of two hours spread over several days because he was “actively fearful of screwing up.”

But fear of failure can take you only so far. Because of rampant sleep deprivation, most men and women in uniform rely on stimulants to stay awake. Chief among them is caffeine. Soldiers guzzle the stuff, starting in boot camp. As they move up the ranks, most graduate from high-caffeine, high-sugar drinks such as Red Bull, Jolt, and neon-green Mountain Dew and turn to super-caffeinated coffee. One popular brand, Ranger Coffee, mixes Arabica coffee beans with additional liquid caffeine. The result is so potent that each bag comes with a label warning that it is not for the faint of heart.

Caffeine is popular as a stimulant because it readily crosses the barrier between the blood and the brain. Once in the brain, it blocks the absorption of adenosine, a nucleotide that slows down nerve connections and makes you feel drowsy. The result is like being able to drive a car backward to roll back the odometer. In research studies, caffeine helped sleep-deprived subjects better discriminate between colors, sort words according to their meaning faster, and see in the dark more clearly. The effect is so powerful that some soldiers resort to eating frozen coffee grounds to stay awake in the field. In the late 1990s, military researchers received a quarter of a million dollars to develop caffeinated gum as an alternative. Gum is ideal if you really need caffeine in a hurry: it allows the stimulant to be absorbed through the tissues in the mouth and reach the brain about five times faster than a pill or coffee. By the 2001 invasion of Afghanistan, pieces of gum that packed 100 milligrams of caffeine—a little bit more than a shot of espresso at Starbucks—were a standard part of soldiers rations. Packets are currently available to civilians on Amazon.com, each one stamped with the hard-sell slogan “Stay Awake, Stay Alive.”

When caffeine doesn’t do the trick, pharmaceuticals take over. Soldiers in combat have turned to amphetamines since World War II. The military restricts most soldiers from taking the pills—which are essentially speed—without a doctor’s prescription, but they are common among certain occupations. Pilots, for instance, routinely take orange “go pills” before night missions, and sometimes take another dose while in the cockpit. The surge in energy comes with a cost. In addition to making it harder to achieve deep sleep once the effect of the stimulant wears off, taking amphetamines can lead to increased aggression and paranoia. Go pills were cited as a contributing factor in a 2001 accident where two American pilots dropped a bomb on an elite Canadian army unit during a live-fire exercise in a remote area of Afghanistan, killing four of them.

Modafinil, marketed to consumers as Provigil in the United States and as Alertec in Canada, is the newest drug found in a soldier’s medicine cabinet. Though scientists aren’t sure exactly how the drug works on the brain, it appears to increase serotonin levels in the brain stem. Some who have taken the pill reported staying up for thirty straight hours without a noticeable drop-off in ability. But evidence suggests that one danger of the drug is that a user doesn’t realize the effects of sleep deprivation. In research studies, sleep-deprived soldiers who downed modafinil were overconfident in their abilities for several hours after taking a dose. The surge in confidence led them to becoming blasé about taking risks they might have otherwise avoided.

They were more fun to be around, however. In one of the high points of military research, army psychologists decided to test whether the use of stimulants influenced the ability to detect and appreciate humor. Getting a joke is tougher than it looks. In the milliseconds between seeing or hearing something and recognizing that it is funny, the brain goes through complex forms of higher thought, such as recognizing patterns, understanding abstract concepts, and appreciating gaps in logic. Test subjects were kept awake for forty-six hours and then shown a series of cartoons and newspaper headlines as part of the Humor Appreciation Test developed by the University of Pennsylvania. Subjects who were given modafinil scored significantly higher than those who drank coffee, suggesting that the drug improved their cognitive performance.

No drug or procedure has been found to replicate and replace the benefits of sleep. It is unlikely that there ever will be. The Defense Advanced Research Projects Agency—the Pentagon division responsible for the invention of the Internet and the stealth bomber—concluded as much in 2007 after many tries. Its goal was to develop a way for a soldier to go without sleep for one hundred hours and still perform common tasks. The military spent millions of dollars testing theories, such as whether it would be possible to put half of the human brain asleep at a time, essentially allowing a person to sleep like a dolphin. None of the tests worked. The only way to recover from lost sleep was to get more of it later.

The invasion of Iraq prompted the U.S. military to rethink the way it approached sleep. The public reason given for the change was that the service needed to keep enrollment numbers up to meet the demands of fighting two wars. Drill sergeants were instructed to spend less time yelling at recruits in boot camp and more time talking with them about their personal goals. At the mess hall, soldiers suddenly had the option of dessert after most meals. Sleeping periods were extended by more than an hour, with lights out at 9:00 p.m. and wake-up at 5:30 a.m. “It has been great for morale,” one drill sergeant said at the time. “A soldier’s happiness is directly proportional to the amount of sleep he gets.”