// essays //
Fall 2007
Engineering the Sleepless Soldier
Evan Daar
Jack Bauer is a non-stop fighting machine. On any given day, the star of Fox's hit TV show "24" is seen fending off a nuclear attack on Los Angeles, preventing terrorists from releasing nerve gas in major U.S. cities, or stopping the meltdown of hundreds of nuclear power plants. All these, and Bauer doesn't show a hint of fatigue.
The reason is simple: Jack Bauer doesn't sleep. He waits, always poised to attack at a moment's notice.
In recent years, the U.S. military has begun to wonder whether the Jack Bauer model of sleeplessness can be replicated in U.S. soldiers, and they have enlisted Columbia University doctors and researchers for help.
The Defense Advanced Research Projects Agency (DARPA)—the Pentagon's research wing that developed such out-of-the-box ideas as the stealth bomber and the Internet—is working "to define and implement approaches to prevent the harmful effects of sleep deprivation."
Sleep is of particular importance to soldiers in the military. For them, sleep is a matter of life and death. With 24-hour missions not uncommon for many soldiers, they must be able to forego sleep for extended periods of time and still function on high physical and mental planes.
The military has long been aware of sleep's importance and the harmfulness of sleep deprivation. To improve stamina, then, soldiers are trained early in their careers to stay awake for extended periods of time. In basic training, recruits sometimes sleep less than three hours per night. In addition, soldiers' physical training builds up their endurance, which can later be used to fight the effects of sleep deprivation.
"You get good at it after a while," explains Garth Stewart, GS '09, and an Iraq War veteran. "Once I had done it for a couple of years, I got used to it. I started to need less sleep." Stewart's ability to stay awake proved vital in Iraq, where he would get between two and three hours of sleep per night during the invasion. His and other soldiers' abilities to stay awake were important strategic assets as well. Stewart explains that soldiers in his platoon would alternate their two-hour sleep shifts, so that the platoon was operational twenty-four hours a day. "When the sun sets, we're still driving. If you never stop, no Iraqi unit is ever going to be able to catch up," Stewart explains.
Some military missions demand that soldiers stay awake for more than 24 hours at a time. In these cases, natural abilities are insufficient to keep soldiers active and effective. The Army has found that men lose 50% of cognitive abilities for every 24 hours without sleep. This means that after 96 hours, soldiers lose the ability to follow simple commands. This timeline is shortened dramatically if any physical exertion is involved, which always is the case in the military.
Since World War II, amphetamines have been issued by the military to help soldiers maintain high performance during extended missions. "Go pills," as they are commonly called in the military, are particularly popular in the Air Force, where sleep deprivation has caused more deaths among pilots in the last two decades than combat operations have. The pills are intended to increase consciousness and stabilize sleep patterns. However, these positive results come with potentially dangerous side effects. In April 2002, sleep-weary American fighter pilots accidentally bombed a team of Canadian troops in Afghanistan while on a mission. In the weeks leading up to the accident, the troops complained to their commanding officer that they needed more rest between missions. In response, they were given "go pills" and told to continue their regular mission schedule. After the friendly fire accident, the soldiers defended themselves in court by blaming their mistake on the pills.
Tragedies like the fighter pilot accident in Afghanistan are part of the motivation for DARPA's research on the science of sleep deprivation. Four years ago, DARPA approached Dr. Yaakov Stern, Professor of Clinical Neuropsychology at Columbia Medical School, with the idea of the sleepless soldier. Given Stern's background in cognitive neuroscience, particularly his interest in the neurological differences between young and old people, DARPA wondered whether Stern's experience with studying the brain could be transferred to the study of sleep deprivation. Stern accepted the challenge.
To begin his study, Stern recruited a group of volunteers who were willing to stay awake for forty-eight consecutive hours, starting on a Tuesday morning. "For every person we screened, only a few actually participate," said Stern. When people did volunteer, staying awake for the full forty-eight hours was a difficult challenge. "Wednesday morning is the real trough for people," Stern said. "If they can make it through that Wednesday morning, they will make it through the whole study."
The participants were placed in a "sleep lab" where they perform various cognitive tasks while being closely monitored by functional magnetic resonance imaging, or fMRI. The technique involves scanning the subject's brain to determine patterns of activation. To do this, Stern and his team observed which areas of the brain received increased blood flow—a proxy for determining which area of the brain was at work—during particular activities.
Stern tested his subjects' memories and, using fMRI scans, observed how their performances changed as a result of sleep deprivation. Stern was eventually able to isolate the areas of the brain responsible for the effects of sleep deprivation in humans—two spots just above the left ear called the lateral occipital gyrus and the infra-parietal cortex. Together, these two areas constitute a brain network.
Both of these areas in the brain network are involved in visual perception. The first area – the lateral occipital gyrus – is largely responsible for helping people to understand the shape and form of an object. The second area—the infra-parietal cortex—helps people understand the spatial positioning of an object they are looking at. Normally, these two areas of the brain work together constantly to allow for clear visual activity. But when these areas are sleep-deprived, they decrease their activity significantly, making visual perceptions much less clear and precise.
Once Stern had identified the brain network affected by sleep deprivation, the next step was to see if he could manipulate that network in order to improve people's abilities to cope with sleep deprivation. To do this, he enlisted the help of fellow-Medical Center Professor Dr. Sarah Lisanby, Chief of the Columbia Brain Stimulation and Neuromodulation Division. Lisanby specializes in a brain-stimulating technique known as transcranial magnetic stimulation, or TMS. According to Lisanby, "TMS is a brief but powerful magnetic field that sends electrical pulses into the brain to activate specific areas."
Together, the two scientists hoped to use TMS to stimulate the sleep-deprived brain network in order to improve their subjects' cognitive abilities after forty-eight hours without sleep. "The idea was that if we could manipulate expression of that network, we could change performance," says Stern.
The initial findings of the study were encouraging. "We could see slight improvement in reaction times in people who were manipulated with TMS," Stern explained. In addition, Stern found that "the people who showed greatest change in the [identified] network, were the people who benefited the most." In other words, the subjects whose brains responded the most to TMS also exhibited the most improvement in handling sleep deprivation. This confirmed the concept that there is a link between certain brain networks and visible human activity. That is, by manipulating a particular brain network, it is also possible to affect the activity associated with it.
So, will the U.S. military be using TMS on soldiers in the near future? Despite Stern's work, he does not think so.
"It would be very hard to implement in real world situations," mostly because of the bulky equipment and the sensitivity of TMS treatment, Stern said. The scientific team thought about the possibility of creating a scaled-down TMS device for military use, and DARPA provided funding for one such study several years ago. However, neither effort yielded much success. For now, Stern's findings are not ready to be used widely outside his lab.
Does this mean that Stern's study was a failure? After all, Stern did not accomplish the task originally delegated to him by DARPA: to help engineer a process to fight the effects of sleep deprivation in soldiers.
Many have asked this bottom-line question, as Stern's study is only one in a long line of controversial DARPA-funded studies. For years, Congressmen have questioned the worth of many of DARPA's projects. They have complained that few DARPA projects actually yield concrete results. In 2003, Congress acted on this rationale; it cut millions of dollars from DARPA's annual budget and eliminated funding altogether for some of the more controversial programs. "We're unclear on the defense applications of some of the research," a Senate Appropriations Committee spokesperson announced. Many members of Congress believe there are better uses of taxpayer money than DARPA's high-risk, high-reward research projects.
Congress's budget cuts raise important questions about the intersection of politics and scientific research. Do members of Congress have the expertise to decide which research projects are worthy of funding and which are not? Or, without proper Congressional oversight, will the federal government's research agencies spiral out of control, conducting research that has no obvious public benefit?
The fight between Congress and DARPA is only one example of the complicated relationship between politics and science. In 2004, the budget for the National Institutes of Health (NIH) included funding for five studies into human sexual behavior. One of the studies proposed to investigate "American Indian and Alaskan Native lesbian, gay, bisexual, transgendered, and two-spirited individuals...who are a drastically understudied and underserved group." Another study's plan was summarized as follows: "mood and sexual arousal will be induced and their individual and combined effects on sexual risk taking will be examined." Congressman Pat Toomey (R-PA) and others were not convinced that these studies were worthy of federal funding. Toomey presented an amendment to the NIH budget that would have cut the funding for all five of the studies, claiming that the public benefit of the studies was almost nothing.
On their face, research projects like the NIH sexual behavior studies—and even DARPA's sleepless soldier study—do appear suspect. One could make a good case that money spent on lesbian and transgender American Indians or sleepless volunteers at Columbia is better spent on cancer or AIDS research. But who should ultimately decide what constitutes a legitimate area of scientific research? Or more specifically, in the case of the DARPA sleep study, who is to decide whether a particular study yielded positive results?
Stern is careful to stress the incremental nature of scientific progress. The stealth bomber and the Internet—two of the most famous DARPA projects—are rare exceptions in the world of scientific research. Scientific inquiry progresses one step at a time. Typically, one scientific study will make a small, incremental addition to a vast field of pre-existing research. The DARPA sleep study is no different. The study conducted in the Columbia Medical School lab provides for "a whole model with which to test the other studies going on right now," says Stern. For instance, Stern now wonders whether his findings will contribute to more research that might help improve the quality of people's sleep.
It is also possible that a scientist studying something in one field will discover something that is applicable in other fields. Stern thinks this might have happened with his sleep deprivation research for DARPA. He argues that he may be able to "use this whole study as a model for how to proceed with something like aging." Using the knowledge he has gained from the DARPA study, Stern plans to address the following question: "Can I intervene and improve cognition in people with Alzheimer's?"
So while we may have to wait for an army of Jack Bauers, DARPA's initiation of research by Stern and his Columbia colleagues may have a ripple effect across the scientific community. The results of the sleep study may help scientists of many stripes to understand the relationship between sleep, weariness, and the brain. And this relationship may have significant impact on the fight against Alzheimer's, or in helping emergency department doctors, airline pilots, and truck drivers to stay awake and alert for long periods of time. In the end, it is important to keep in mind the incremental nature of scientific research and not to expect all studies to yield the next stealth bomber. As Stern explains, the "research we did here was relevant to understanding cognition and sleep deprivation, which is a real problem in this country."
The reason is simple: Jack Bauer doesn't sleep. He waits, always poised to attack at a moment's notice.
In recent years, the U.S. military has begun to wonder whether the Jack Bauer model of sleeplessness can be replicated in U.S. soldiers, and they have enlisted Columbia University doctors and researchers for help.
The Defense Advanced Research Projects Agency (DARPA)—the Pentagon's research wing that developed such out-of-the-box ideas as the stealth bomber and the Internet—is working "to define and implement approaches to prevent the harmful effects of sleep deprivation."
Sleep is of particular importance to soldiers in the military. For them, sleep is a matter of life and death. With 24-hour missions not uncommon for many soldiers, they must be able to forego sleep for extended periods of time and still function on high physical and mental planes.
The military has long been aware of sleep's importance and the harmfulness of sleep deprivation. To improve stamina, then, soldiers are trained early in their careers to stay awake for extended periods of time. In basic training, recruits sometimes sleep less than three hours per night. In addition, soldiers' physical training builds up their endurance, which can later be used to fight the effects of sleep deprivation.
"You get good at it after a while," explains Garth Stewart, GS '09, and an Iraq War veteran. "Once I had done it for a couple of years, I got used to it. I started to need less sleep." Stewart's ability to stay awake proved vital in Iraq, where he would get between two and three hours of sleep per night during the invasion. His and other soldiers' abilities to stay awake were important strategic assets as well. Stewart explains that soldiers in his platoon would alternate their two-hour sleep shifts, so that the platoon was operational twenty-four hours a day. "When the sun sets, we're still driving. If you never stop, no Iraqi unit is ever going to be able to catch up," Stewart explains.
Some military missions demand that soldiers stay awake for more than 24 hours at a time. In these cases, natural abilities are insufficient to keep soldiers active and effective. The Army has found that men lose 50% of cognitive abilities for every 24 hours without sleep. This means that after 96 hours, soldiers lose the ability to follow simple commands. This timeline is shortened dramatically if any physical exertion is involved, which always is the case in the military.
Since World War II, amphetamines have been issued by the military to help soldiers maintain high performance during extended missions. "Go pills," as they are commonly called in the military, are particularly popular in the Air Force, where sleep deprivation has caused more deaths among pilots in the last two decades than combat operations have. The pills are intended to increase consciousness and stabilize sleep patterns. However, these positive results come with potentially dangerous side effects. In April 2002, sleep-weary American fighter pilots accidentally bombed a team of Canadian troops in Afghanistan while on a mission. In the weeks leading up to the accident, the troops complained to their commanding officer that they needed more rest between missions. In response, they were given "go pills" and told to continue their regular mission schedule. After the friendly fire accident, the soldiers defended themselves in court by blaming their mistake on the pills.
Tragedies like the fighter pilot accident in Afghanistan are part of the motivation for DARPA's research on the science of sleep deprivation. Four years ago, DARPA approached Dr. Yaakov Stern, Professor of Clinical Neuropsychology at Columbia Medical School, with the idea of the sleepless soldier. Given Stern's background in cognitive neuroscience, particularly his interest in the neurological differences between young and old people, DARPA wondered whether Stern's experience with studying the brain could be transferred to the study of sleep deprivation. Stern accepted the challenge.
To begin his study, Stern recruited a group of volunteers who were willing to stay awake for forty-eight consecutive hours, starting on a Tuesday morning. "For every person we screened, only a few actually participate," said Stern. When people did volunteer, staying awake for the full forty-eight hours was a difficult challenge. "Wednesday morning is the real trough for people," Stern said. "If they can make it through that Wednesday morning, they will make it through the whole study."
The participants were placed in a "sleep lab" where they perform various cognitive tasks while being closely monitored by functional magnetic resonance imaging, or fMRI. The technique involves scanning the subject's brain to determine patterns of activation. To do this, Stern and his team observed which areas of the brain received increased blood flow—a proxy for determining which area of the brain was at work—during particular activities.
Stern tested his subjects' memories and, using fMRI scans, observed how their performances changed as a result of sleep deprivation. Stern was eventually able to isolate the areas of the brain responsible for the effects of sleep deprivation in humans—two spots just above the left ear called the lateral occipital gyrus and the infra-parietal cortex. Together, these two areas constitute a brain network.
Both of these areas in the brain network are involved in visual perception. The first area – the lateral occipital gyrus – is largely responsible for helping people to understand the shape and form of an object. The second area—the infra-parietal cortex—helps people understand the spatial positioning of an object they are looking at. Normally, these two areas of the brain work together constantly to allow for clear visual activity. But when these areas are sleep-deprived, they decrease their activity significantly, making visual perceptions much less clear and precise.
Once Stern had identified the brain network affected by sleep deprivation, the next step was to see if he could manipulate that network in order to improve people's abilities to cope with sleep deprivation. To do this, he enlisted the help of fellow-Medical Center Professor Dr. Sarah Lisanby, Chief of the Columbia Brain Stimulation and Neuromodulation Division. Lisanby specializes in a brain-stimulating technique known as transcranial magnetic stimulation, or TMS. According to Lisanby, "TMS is a brief but powerful magnetic field that sends electrical pulses into the brain to activate specific areas."
Together, the two scientists hoped to use TMS to stimulate the sleep-deprived brain network in order to improve their subjects' cognitive abilities after forty-eight hours without sleep. "The idea was that if we could manipulate expression of that network, we could change performance," says Stern.
The initial findings of the study were encouraging. "We could see slight improvement in reaction times in people who were manipulated with TMS," Stern explained. In addition, Stern found that "the people who showed greatest change in the [identified] network, were the people who benefited the most." In other words, the subjects whose brains responded the most to TMS also exhibited the most improvement in handling sleep deprivation. This confirmed the concept that there is a link between certain brain networks and visible human activity. That is, by manipulating a particular brain network, it is also possible to affect the activity associated with it.
So, will the U.S. military be using TMS on soldiers in the near future? Despite Stern's work, he does not think so.
"It would be very hard to implement in real world situations," mostly because of the bulky equipment and the sensitivity of TMS treatment, Stern said. The scientific team thought about the possibility of creating a scaled-down TMS device for military use, and DARPA provided funding for one such study several years ago. However, neither effort yielded much success. For now, Stern's findings are not ready to be used widely outside his lab.
Does this mean that Stern's study was a failure? After all, Stern did not accomplish the task originally delegated to him by DARPA: to help engineer a process to fight the effects of sleep deprivation in soldiers.
Many have asked this bottom-line question, as Stern's study is only one in a long line of controversial DARPA-funded studies. For years, Congressmen have questioned the worth of many of DARPA's projects. They have complained that few DARPA projects actually yield concrete results. In 2003, Congress acted on this rationale; it cut millions of dollars from DARPA's annual budget and eliminated funding altogether for some of the more controversial programs. "We're unclear on the defense applications of some of the research," a Senate Appropriations Committee spokesperson announced. Many members of Congress believe there are better uses of taxpayer money than DARPA's high-risk, high-reward research projects.
Congress's budget cuts raise important questions about the intersection of politics and scientific research. Do members of Congress have the expertise to decide which research projects are worthy of funding and which are not? Or, without proper Congressional oversight, will the federal government's research agencies spiral out of control, conducting research that has no obvious public benefit?
The fight between Congress and DARPA is only one example of the complicated relationship between politics and science. In 2004, the budget for the National Institutes of Health (NIH) included funding for five studies into human sexual behavior. One of the studies proposed to investigate "American Indian and Alaskan Native lesbian, gay, bisexual, transgendered, and two-spirited individuals...who are a drastically understudied and underserved group." Another study's plan was summarized as follows: "mood and sexual arousal will be induced and their individual and combined effects on sexual risk taking will be examined." Congressman Pat Toomey (R-PA) and others were not convinced that these studies were worthy of federal funding. Toomey presented an amendment to the NIH budget that would have cut the funding for all five of the studies, claiming that the public benefit of the studies was almost nothing.
On their face, research projects like the NIH sexual behavior studies—and even DARPA's sleepless soldier study—do appear suspect. One could make a good case that money spent on lesbian and transgender American Indians or sleepless volunteers at Columbia is better spent on cancer or AIDS research. But who should ultimately decide what constitutes a legitimate area of scientific research? Or more specifically, in the case of the DARPA sleep study, who is to decide whether a particular study yielded positive results?
Stern is careful to stress the incremental nature of scientific progress. The stealth bomber and the Internet—two of the most famous DARPA projects—are rare exceptions in the world of scientific research. Scientific inquiry progresses one step at a time. Typically, one scientific study will make a small, incremental addition to a vast field of pre-existing research. The DARPA sleep study is no different. The study conducted in the Columbia Medical School lab provides for "a whole model with which to test the other studies going on right now," says Stern. For instance, Stern now wonders whether his findings will contribute to more research that might help improve the quality of people's sleep.
It is also possible that a scientist studying something in one field will discover something that is applicable in other fields. Stern thinks this might have happened with his sleep deprivation research for DARPA. He argues that he may be able to "use this whole study as a model for how to proceed with something like aging." Using the knowledge he has gained from the DARPA study, Stern plans to address the following question: "Can I intervene and improve cognition in people with Alzheimer's?"
So while we may have to wait for an army of Jack Bauers, DARPA's initiation of research by Stern and his Columbia colleagues may have a ripple effect across the scientific community. The results of the sleep study may help scientists of many stripes to understand the relationship between sleep, weariness, and the brain. And this relationship may have significant impact on the fight against Alzheimer's, or in helping emergency department doctors, airline pilots, and truck drivers to stay awake and alert for long periods of time. In the end, it is important to keep in mind the incremental nature of scientific research and not to expect all studies to yield the next stealth bomber. As Stern explains, the "research we did here was relevant to understanding cognition and sleep deprivation, which is a real problem in this country."
//Evan Daar is a junior in Columbia College majoring in Economics.