Soldiers can walk away from the battlefield with no visible wounds but still be suffering from traumatic brain injuries that might haunt them later even if they don't, as is also possible, immediately become a problem in combat.

Hidden injuries imposed on the brain by exposure to the high-pressure shock waves of explosives – a particular problem in Iraq and Afghanistan, where rocket attacks and improvised explosive devices are prominent features of the conflicts – can leave military personnel disoriented.

"You may not be thinking as clearly as you could," University of Illinois Professor Kenneth Watkin said recently. "These young people are in the presence of a lot of explosions every day."

The damage, which Watkin said sometimes doesn't show up for days after – even if it's somewhat severe – could lead to bad decisions, like horrific friendly fire incidents with troops firing on their own.

Moreover, it could lead to physical and cognitive problems – trouble concentrating, memory loss, fatigue, lack of coordination – long after soldiers come home. Behavioral or mood changes also might result.

Watkin and UI colleagues think they can help reduce the damage, however, by identifying early and in real time signs that a soldier may be nearing the critical point on the way to a traumatic brain injury.

They plan to do it by getting into soldiers' heads, so to speak, through a handy avenue: their helmets.

The "smart helmet" technology being developed by Watkin, a UI speech and hearing science professor, Ravi Iyer, an electrical and computer engineering professor and head of the Coordinated Science Lab, and other collaborators would equip standard military helmets with tiny sensors to monitor brain activity and blast intensity, among other things.

The system also is supposed to transmit data from the nano-sized sensors wirelessly, perhaps by satellite to remote doctors half a world away at, say, Walter Reed Army hospital in Washington, D.C.; to emergency medical personnel in the field with cell-phone like handheld receivers; or to soldiers themselves, setting off a warning buzzer or vibrator when brain damage might be imminent.

Besides soldiers, the system could be useful for emergency personnel such as firefighters, as well as for miners and for football players, as well as other helmet-wearing folks whose professions expose them to a risk of traumatic brain injury, Watkin said.

Developing and integrating the hardware involved, from the sensors to the wireless technology, is only one challenge. Watkin and Iyer say the bigger task for the UI researchers may be learning how to translate the sensor data into a useful, ongoing assessment of traumatic brain injury, as well as developing software to do it efficiently and reliably.

Watkin, who also is a professor with the UI College of Medicine, counts high-definition 3-D imaging of the brain for diagnostic and therapeutic purposes among his research focuses. When he saw the Army calling for new concepts in addressing traumatic brain injury under a congressionally mandated program stemming from the Middle East wars, he and Iyer, who brings computer science expertise to the team, decided to apply. They already were collaborating on a UI initiative involving large-scale monitoring of health conditions.

They won a Concept Award grant from the Department of Defense, which basically gives them a year to show they can do what they're proposing.

UI researchers Zbigniew Kalbarczyk, Janak Patel, William Sanders and Mark Spong, all members of the UI Information Trust Institute, also are collaborating on the project.

The idea is to embed the sensors in the straps and padding inside soldiers' helmets, along with a circuit board, at this point one the size of a postage stamp with a processor, the brain of a computer, about the size of a small thumbtack's head.

The system, which Iyer characterized as "a small-footprint, low-power hardware computing platform," could be powered easily by the batteries today's electronics-equipped soldiers already carry.

The sensors are to be designed to poll oxygen saturation in the brain, a sign of changes there if desaturation occurs; pressure from blast waves; and the speed at which the subject's head is being pushed around. The system also will capture the brain's electrical activity and other vital signs, such as heart rate, and combine them, theoretically, to predict the soldier's status.

Watkin discussed the project in terms of the parable of the blind men who touched different parts of an elephant – trunk, leg, tusk, ear – and came up with widely varied impressions of its appearance. The UI researchers are trying to create a system that discerns the whole elephant.

"That's what we're looking for," Watkin said, "that entire picture."