One of the next steps for the researchers is to couple the pressure-wave information with structural-analysis algorithms that model the head to see how these applied pressures would be transmitted into the soft matter of the brain. Computational models that allow scientists to see how the wave hits the brain will help them better understand what is happening neurologically, says Radovitzky.

Mott says that the eventual goal is to create a system to be used in triage so that medical personnel can download an injured soldier's blast-exposure history and treat him accordingly.

The researchers' findings could ultimately improve helmet designs and better protect soldiers in the field. They are collaborating with another team of NRL scientists who are designing small sensors that can be embedded in a soldier's helmet to record key information about exposure to a blast. Other teams are doing similar work: last year, the U.S. Army awarded a million-dollar contract to Simbex, of Lebanon, NH, to build sensor-studded helmets; more recently, the U.S Defense Advanced Research Project Agency (DARPA) awarded a three-year contract worth $5 million to the Palo Alto Research Center (PARC) to develop a simple plastic strip that can be "taped" onto a soldier's helmet to measure the intensity of an explosion.