More attention is being paid to the rate and severity of brain injuries in American soldiers serving in Iraq and Afghanistan. Field studies, conducted on soldiers in both wars, have found that more than 10 percent of soldiers have suffered a brain injury or concussion.

While concussions are nothing new, the injuries suffered by soldiers serving overseas are unique. Thousands suffer from concussions in the United States every year. Most concussions are instigated by a blow to the head, such as those received in football games.

In Iraq and Afghanistan, most concussions are caused by explosions - more specifically, the explosion's blast wave.

Put simply, a blast wave is characterized by a large displacement of energy within a small area. Roadside bombs and homemade explosives, common in both countries, are the main cause for these blast wave brain injuries among soldiers.