While a person sleeps, her cells undergo a cycle of repair that provides both oxygen and glucose. When a person stays up all night, the brain’s cells are denied the products of this cycle, severely hampering the organs’ reactions to stimuli and instructions. “Every cell in our body needs food and it produces waste, so all those things occur in a regular, regimented way when we’ve slept well. And when we interfere with that, systems go out of sync,” Walseben said.
Feinsilver said that while we sleep, the blood stream is cleared of a substance that researchers call “substance S.” Many believe substance S is adenosine, a byproduct of energy production that cells release into the blood throughout waking hours. He said that without sleep, the blood gets clogged with substance S, slowing a person down from head to toe.
“It looks like there’s a toxic substance building up in you, where the more you’re awake, the more you see this stuff floating around the bloodstream, and the only way to get rid of it is to sleep,” he said.
While I was awake in Europe, my reaction time was horribly off and my ability to concentrate fell apart, and I became increasingly clumsy and weak. Today, I still feel like I have more difficulty concentrating than I did beforehand. It might just be my imagination. I will probably never be sure.
Many sleep researchers study people who have partial sleep deprivation. These subjects have social jetlag; in a typical sleep lab, they might sleep four hours or so every night for one week. But the experts I interviewed said that less is known about total sleep deprivation and its lasting impacts because researchers have moral concerns about forcing people to stay awake.
“Once you are up all night, by mid-afternoon, it becomes unbearable,” Feinsilver said. “You can do it, but it’s really torture.”
“You know what people might be doing that?” he added. “The army.”
A 2007 report on American torture tactics—written by non-governmental organizations Physicians for Human Rights and Human Rights First—has a section on sleep deprivation that begins with descriptions of a Soviet gulag. In The Gulag Archipelago, Alexandr Solzhenitsyn lists sleeplessness as one of 31 methods that his captors used to break a prisoner’s will. “Sleeplessness befogs the reason, undermines the will, and the human being ceases to be himself, to be his own ‘I,’” Solzhenitsyn writes. He says that guards in the gulag kept prisoners awake for up to five days by perpetually standing them up or by kicking them when their eyes drooped. The author quotes an inmate who endured this, listing his many symptoms, including chills, eyes “dried out as if someone were holding a red-hot iron in front of them,” a swollen and prickling tongue and a throat racked with spasms. “Sleeplessness was a great form of torture: it left no visible marks and could not provide grounds for complaint even if an inspection—something unheard of anyway—were to strike on the morrow,” Solzhenitsyn writes.
Because sleep deprivation “leaves no marks” and is believed to break a detainee’s will, across the world, the tactic has been adopted by government and security forces, notably by Chilean dictator Augusto Pinochet in the 1970s. Most notoriously, sleep deprivation has been used on several prisoners at the United States’ Guantánamo Bay prison camp in Cuba.
In the middle of the night, on May 7, 2004, American officers unshackled Afghan Guantánamo detainee Mohammed Jawad; they moved him to another cell, and re-shackled him. Three hours later, Jawad was unshackled, moved, and re-shackled again. Over 14 days, Jawad was moved from cell to cell 112 times. In response to motions filed by Jawad and the ACLU, the military claimed in court that, as a result of the tactic, Jawad had not suffered permanent physical harm, and that the long-term psychological damage to Jawad had been “unclear.” But some specific effects that this program had on Jawad are known. According to reports by the Associated Press and Jawad’s lawyers, he lost 10 percent of his body weight while sleep deprived. In a legal claim against the government arguing that Jawad’s imprisonment was illegal under habeus corpus, ACLU lawyers also wrote that while kept awake, Jawad had blood in his urine. “The torture, cruelty, and harsh treatment to which Mohammed has been subjected throughout his six years in U.S. custody have resulted in severe and ongoing psychological harm,” they concluded.
Rather than kicking prisoners, as the Soviets did, Guantánamo guards kept prisoners awake by chaining their feet and wrists to the floor of their cell, so they could not fall over without being caught by the chains, and moving prisoners between cells every two or three hours. This sleep deprivation program was referred to as the “frequent-flyer” program, or “Operation Sandman,” and was used against at least 17 GITMO detainees, according to the military’s own logs kept at the prison in 2003 and 2004. In memos authorizing the program that were de-classified in 2009, Justice Department lawyers asserted that sleep deprivation works well as an interrogation technique, because it breaks down detainees’ ability to resist coercion, and because it decreases prisoners’ tolerance for physical pain. In 2012, a letter from British detainee Shaker Aamer asserted that despite being formally banned in 2009, the frequent flyer program was still in use at the prison.