She was 42 when she suffered a stroke, and in the aftermath she was like a prisoner in her own body: conscious and aware, able to hear and feel, but unable to move or communicate. After a decade, she was able to shake her head from side to side, but the prospects for further recovery were bleak. Today, however, thanks to an implant that links her brain to a computer, the neural signals that once guided routine movements have been able to control an on-screen keyboard and guide a robotic arm.
These are tantalizing early steps toward the long-held dream of rehabilitation experts and, more recently, of researchers in neurotechnology, says Leigh R. Hochberg, a neuroengineer and doctor who specializes in brain-computer interface systems. “Many injuries and diseases can result in an inability to move, and often an inability to speak, but still leave cognition completely intact,” he explained at a recent AAAS briefing on Capitol Hill. “We’re hoping to develop technologies that will restore the ability to communicate and restore the ability to move.”
The briefing focused on the military applications of neuroscience, but Hochberg told the story of the stroke victim to illustrate how advances in neuroscience may transform once-futuristic ideas into better lives for soldiers, accident victims, and others. Researchers are learning how to expand and manipulate the powers of the human brain—through drugs, new technologies, even exotic methods of brain stimulation—creating a world of promise. And yet, speakers at the briefing offered a caution: As that promise comes to fruition, society will have to address an array of complex social and ethical issues arising from the science of brain enhancement.
The issues will be debated “at the intersection of science and society,” said briefing moderator Alan I. Leshner, the chief executive officer of AAAS and executive publisher of Science. “These issues are emerging now and will only get more prominent over time.”
About 100 congressional staffers and others attended the 90-minute briefing, held 26 July in cooperation with the House Armed Services Committee and with financial support from The Dana Foundation. The AAAS Office of Government relations has scheduled a second neuroscience briefing—on possible links between cell phones and brain tumors—for 7 September. The third and final briefing in the series, on traumatic brain injury, will be held in October.
Understanding the brain’s functions and malfunctions was an interest of the U.S. defense and security sectors long before the term “neuroscience” was coined. After World War I, there were studies of “shell shock” (known now as post-traumatic stress disorder, or PTSD). During the Cold War, there was a focus on brainwashing and even on extra-sensory perception and the possible uses of hallucinogenic drugs. Today, the military is exploring other realms of neuroscience research with a range of possible benefits: making soldiers better fighters; helping them to recover from mental stresses and physical injuries after battle; and assisting in interrogation of enemy soldiers.
Leigh R. Hochberg
Jonathan D. Moreno
Jonathan D. Moreno, an historian and ethicist at the University of Pennsylvania, detailed the Pentagon’s extensive 2011 neuroscience investments: Army, $55 million; Navy, $34 million; Air Force, $24 million; and the Defense Advanced Research Projects Agency (DARPA), more than $240 million.
The Routes to “Cognitive Enhancement”
Martha J. Farah
Martha J. Farah, director of Penn’s Center for Neuroscience & Society, said a key neuroscience interest for the military is cognitive enhancement. And that includes basics often learned early in life.
“Some of the most effective methods of enhancing your brain,” Farah said, “are probably things your grandmother would have recommended—exercise; adequate sleep; practice, practice, practice—that is, training programs; and stress management.”
Another focus is research on drugs. The military has long recognized the value of amphetamines for maintaining alertness, but interest today centers on newer drugs such as amphetamine compounds developed for attention deficit hyperactivity disorder, and modafinil, developed for the treatment of sleep disorders.
“It’s unclear how large or reliable the effects are [at cognitive enhancement], and it’s unclear how they translate in the field,” she explained. “But it is worth noting that, while I want to leave you with a so-so, maybe helpful/maybe not view of these drugs…under conditions of sleep deprivation, there may be an appreciable benefit.”
That’s especially true with modafinil, she said. Moreno told the briefing that the drug could apparently keep someone awake for extended periods without decrease in skill or capacity.
Moreno is the author of Mind Wars: Brain Research and National Defense (Dana Press, 2006), and he served on a National Research Council panel that produced the 2008 report, “Emerging Cognitive Neuroscience and Related Technologies.” He told the briefing that drugs may be useful beyond keeping soldiers awake and alert.
For example, beta blockers are used for reducing stress and are being researched as a possible way to treat—or even prevent—PTSD. “Perhaps you could give somebody a beta blocker before they observed or witnessed a horrible situation, like a combat soldier who had to see or do terrible things,” he explained. Thus far, however, the drugs have not been reliable in that use.
Oxytocin, a naturally produced human hormone, is associated with bonding and feelings of trust and love. In research, a nasal dose has made people more cooperative in competitive games. In Moreno’s view, that raises an interesting question: “Could you give somebody a bolus of oxytocin before the interrogator came into the room, in a difficult place like Guantanamo? Suddenly the next cop who walked in would be the good cop. You wouldn’t have to play the games you have to play according to Chapter 8 of the Army Interrogation Manual.”
Video highlights from the AAAS Capitol Hill briefing, “Neuroscience and the Military”
From 9-Volt Batteries to Mind-Reading Devices
It appears that the brain can be enhanced without drugs, too—with new techniques that direct a weak force from equipment outside the head into a targeted area of the brain. It’s called “non-invasive brain stimulation.” This approach, Farah reported, “is beginning to yield some really interesting results that may be helpful both for treating neuro-psychiatric disease, but also for enhancing people’s cognition.”
Video highlights from the AAAS Capitol Hill briefing, “Neuroscience and the Military”
Research is focusing on two different approaches:
- Transcranial Magnetic Stimulation (TMS), in which alternating magnetic fields stimulate small, specific areas of the brain. The technique can be used either to increase neural activity or to inhibit it. In recent years, TMS has been used to treat depression. But Farah said that laboratory research thus far has found evidence of improved working memory, spatial attention, and motor skill learning, plus enhanced emotional function.
- Transcranial Direct Current Stimulation (TDCS) is, at first glance, low-tech. Using only basic equipment—a 9-volt battery, some wire, plus some gauze and saline for electrodes—a weak current of just a few milliamps is projected into areas of the brain. But, Farah said, the effects are significant: Test subjects show enhanced vocabulary, grammar learning, and verbal fluency, along with improved creative problem-solving.
While these techniques seem extraordinary, others discussed by Moreno seem straight from the realms of science fiction.
It’s been nearly a decade since research on an experimental “robo-rat” were reported; with the placement of three electrodes, including one in the pleasure-center of its brain, researchers could compel the rodent to do all sort of things a normal rodent wouldn’t do.
Since then, new technologies have emerged: Some are experimenting with ultrasound and light as means of stimulating and enhancing brain functions.
Moreno described one DARPA project—he called it a “head web”—that allows researchers to assess a subject’s brain activity at a distance. In a battlefield context, he said, a soldier might wear a helmet that captures signals from the brain; data from an electroencephalogram could be beamed to a satellite and then to battle headquarters, giving planners nearly instant insight into conditions on the battlefield. The same technology might allow doctors to monitor brain activity and changes in a patient with Parkinson’s disease.
Liberating the Neural Signal
Given the legion of war casualties from Iraq and Afghanistan, the research into advanced robotic limbs is acutely important, and over the past five years, research funded by DARPA and others has helped develop a new generation of prosthetics. Hochberg is at the center of efforts to link the human brain to computers—perhaps wirelessly, someday—so that injured military personnel, stroke victims, people with Lou Gehrig’s disease (amyotrophic lateral sclerosis), and others get restored powers of movement and communication.
Hochberg is an associate professor at Brown University and Harvard Medical School, and a principal investigator the Center for Restorative and Regenerative Medicine at the Providence VA Medical Center. Those institutions, along with Massachusetts General Hospital and others, are collaborating in an ambitious initiative called BrainGate, which is working with the support of a dozen federal agencies and private foundations to produce “transformational neurotechnologies.”
When a spinal injury leaves someone paralyzed, Hochberg explained, the brain still generates a signal to move the arm, but the signal never arrives. At scientific meetings, he has described early research in which tiny arrays—about the size of a baby aspirin—are implanted in the brain’s motor cortex; the array picks up that signal, conveys it through a connector atop the skull, then via a thin wire into a computer. There it is decoded and sent on to external assistive devices.
This brain-computer interface allows neural impulses—an intention, a thought—to be translated in real time into action. A patient’s hand may be paralyzed, but if the mind creates the intention to move, the technology might fill in to click letters on an tele-screen keyboard or to move a robotic arm.
The technology is promising, but it’s still in early development. The stroke victim with whom Hochberg has worked doesn’t have a permanent connection to the interface technology; when she has been connected, it doesn’t always work perfectly. In time, Hochberg said, it may advance enough to improve quality of life for a person with tetraplegia, giving them the ability to browse the Web, send emails, or better control a wheelchair. BrainGate has already demonstrated these possibilities.
In the longer term, he said, it may be possible to reconnect mind and body, using sensors and electrodes implanted in the brain and in muscles and nerves to bring paralyzed limbs back to life. “I’m encouraged by what I’ve seen,” he told the briefing, “and I’m optimistic that in the future we’ll be able to develop fully effective neurotechnologies that will restore mobility and independence.”
In the Wake of Progress, Ethical and Social Issues
Such research is remarkable and sure to inspire hope. Just as surely, though, it will raise complex questions. “Once you get into the enhanced ability to do all kinds of things, it raises an array of ethical issues,” said Leshner, the AAAS CEO. “And not only for the military—all of these things will spill over into the broader society.”
Consider the use of beta-blockers as a possible way to neutralize the effects of PTSD. It is a terrible condition, and difficult to treat. But, Moreno asked: “Would it be ethically acceptable…to give soldiers, before they went into combat, something that would isolate their memory of the circumstances from feelings of guilt or remorse or regret?”
Development of the robo-rat raises a range of questions, including issues of animal rights. “You can probably do it with a higher organism as well,” Moreno said, “and who knows how far up the phylogenetics chain you can do this kind of thing?” How will society govern such research? How will it use—or not use—such knowledge?
Even the BrainGate research, while profoundly hopeful, will raise uneasy questions.
The robotic limbs and the brain-computer interface and are very expensive, and are likely to remain so for a long time. Who will get them, then, and who will be denied? How will insurance companies handle them?
Doping scandals in sports offer an insight into how enhancement technology might seep into society. Already, Farah said, modafinil is being used by business travelers to fight jet lag, while amphetamines such as Adderall are widely misused by students who are seeking a performance edge or to stave off the effects of too little sleep.
But the answers are not always black-and-white. If a parent can afford special training or test preparation classes before their child’s grad school admissions exam, Moreno suggested, why not a pill to sharpen thinking just a little more on test day?
“Pretty soon everyone will have access to these things,” he said. “And then the question is: Is that good? To what extent have we undermined the traditional Greek notion that you’re supposed to strive for excellence with your natural abilities?”
For now, though, the potential benefits to people with neurologic disease or injury provide powerful motivation for further research.
Hochberg recalled that the stroke victim had been gardening on the day before she was stricken. For more than 10 years she endured in spite of overwhelming challenges, until the day came when she used her mind to direct the simple movements of a robotic arm.
“As soon as she did this,” he said, “she told us that now what she wants to do is to take this arm and return to her vegetable garden.”
Learn more about the AAAS briefing, “Neurotechnology and the Military,” held 26 July 2011
Learn more about the brain-computer interface technology being explored by BrainGate.