WASHINGTON — For some modern soldiers, caffeine is just not enough to stay vigilant, especially for the growing ranks of digital warriors who must spend hours monitoring spy drone footage and other streams of surveillance data.
So the Pentagon is exploring a novel way to extend troops’ attention spans and sharpen their reaction times: stimulate the brain with low levels of electricity.
It sounds like science fiction, but commanders in search of more effective tools than the ubiquitous cups of coffee and energy drinks are testing medical treatments designed to treat such brain disorders as depression to determine whether they can also improve the attentiveness of sleepdeprived but otherwise healthy troops.
Early experiments using “noninvasive” brain stimulation have been performed on several dozen volunteers at the Air Force Research Laboratory at Wright-Patterson Air Force Base in Ohio. The results show the technique improves both alertness and acuity, researchers say.
“We found that people who receive the stimulation are performing consistently,” R. Andy McKinley, a biomedical engineer who oversees the research, said in an interview.
Project officials want to study the effects further — especially to determine whether it is safe to stimulate the brain regularly — but said there have been few side effects, such as some skin irritation from the electrodes, as well as mild but brief headaches. They expressed confidence that the work could ultimately result in a pair of easy-to-apply electrodes becoming standard issue for some military personnel.
But the hardware is unlikely to be standard issue for civilians any time soon. For now, researchers don’t envision non-military application for the high-tech caffeine high.
The research grew out of a recognition that while computers have automated many military functions, humans are needed in ever-larger numbers to monitor massive amounts of information in order to make crucial battlefield decisions.
“It used to be the people who would win the arm wrestling match would win the war,” said Alan Shaffer, the acting assistant secretary of defense for research and engineering. “In the future it is going to be who can process information most quickly and react to that. If you can’t make sense of all the information coming in around you and get to a decision it has little value.”
For decades what is known more broadly as electroconvulsive therapy carried a stigma — due in large part to early treatments that administered large doses of electricity to psychiatric patients without anesthesia, often causing memory loss, fractured bones, and other serious side effects.
But such therapy now relies on carefully controlled doses of electrical current, which are passed into certain regions of the brain to cause, in effect, a minor seizure, or more rapid nerve impulses. Some of the techniques have been embraced by the National Institute of Mental Health, the American Psychiatric Association, and the US Surgeon General as a valuable tool to treat various psychiatric disorders, especially major depression.
But research into its effects on healthy subjects remains limited.
“There is some evidence that it does seem to work,” said Dr. William “Scott” Killgore, an assistant professor of psychology at Harvard Medical School who specializes in the mental health treatments. “There have been a few studies that if you use it in the right place it can help mathematical calculations when people are sleep-deprived.”
Still, he cautioned, “it is not very precise yet.”
For example, stimulating certain parts of the brain reduces activity in others.
“The hard part is to know what to turn on and what to turn off,” said Killgore, who is involved in a separate Pentagon study to help determine which parts of the brain are most effective to stimulate. “It gets somewhat complicated. It is a really exciting idea but it is slow going.”
The new Pentagon effort is described as one of the most in-depth studies of electric stimulation on healthy individuals.
Specialists call the two different techniques being studied transcranial magnetic stimulation and transcranial direct current stimulation.
The first has been more widely used in the medical community and relies on a magnetic field to pass the electrical current into the brain. The second technique passes electrical current directly into the brain. For example, in one of the tests, one milliampere is applied for 10 minutes; by comparison, the amount of electrical current needed to power a car’s instrument panel is on average about 150 milliamperes.
The Pentagon research is focused on two primary goals: increasing alertness and improving overall cognitive performance.
Monitoring intense streams of data can quickly become so repetitive — especially when there is no action — that attentiveness and recognition can deteriorate in as little as 20 minutes. And troops responsible for analyzing computer images for intelligence information — unlike some pilots or other front-line personnel — are not eligible for prescribed drugs that might help.
“Fatigue is one of the major factors our active duty military endure every day,” said Justin Nelson, one of the project’s researchers.
After undergoing the brain stimulation, however, the test subjects proved alert at the end of the test periods — some up to several hours — “just like they were at minute one,” said McKinley.
According to Lindsey McIntire, another one of the researchers, the brain stimulation demonstrated significantly better results than caffeine “and without the side effects,” such as jitters, elevated heart rates, and the propensity for a person to “crash” when the caffeine wears off.
In one scenario, the test subjects — some who received caffeine, some brain stimulation, and the rest nothing — were kept awake for a full 30 hours to see who would measure best in wakefulness and vigor.
“I wasn’t sure what to expect,” said Staff Sergeant William Raybon, one of the participants. “When I was initially hooked up to the electrodes there was a small tingling sensation.
But he said that despite being so sleep-deprived, he felt “refreshed” after undergoing the treatment.
Subjects such as Raybon who received the brain stimulation “performed about twice as well as people who got nothing,” said McKinley.
As for those who were given coffee?
“Caffeine had tanked at this point,” said McIntire.
Another aspect of the military research is whether the treatments can make troops better thinkers.
In one such test, subjects were required to follow a series of procedures to identify on screen an aircraft entering friendly airspace.
The study, which also relied on control groups that drank coffee or nothing at all, found that those who did not receive one of several types of brain stimulation “performed significantly worse than any of the stimulation groups,” according to the findings.
The Air Force Research Laboratory has conducted five separate studies, each costing about $200,000, shared by the Air Force, Army, and the Defense Advanced Research Projects Agency.
“We are beyond the proof-of-concept phase,” McKinley said. “We are working on something that would be easy to apply that you could potentially field.”
But some specialists such as Killgore aren’t so sure that the science is quite there yet to use on healthy subjects regularly, especially direct currents of electricity, which he said relies on “much newer technology than the other ones.”
McKinley, too, acknowledged that there are still many questions to be answered, especially concerning any long-term effects.
“As far as using it every day, there is almost no data on that,” he said. The Ohio laboratory is “ramping up a study to do that very thing.”