VOA常速英语:Study: Powerful Blasts Uniquely Change Brain’s Structure

Since the First World War scientists have been trying to understand the changes that explosions inflict on soldiers’ brains. The phenomenon known as ‘shell shock’ is still poorly understood, but researchers at Johns Hopkins University have recently discovered some new clues.

Many veterans who survived powerful explosions show symptoms of psychological injuries, such as mood swings, violent outbursts, difficulty to concentrate or depression.

As with people who died in transportation accidents or from drug overdoses, their brains show physical damage. But researchers at the Johns Hopkins School of Medicine say close examination of the brains of veterans who died of other causes shows a pattern of swollen and broken nerve fibers concentrated in the frontal lobe.

“And that's very important because this is the site, the center, of the executive functions of the brain. Functions that allow you to put your life together, organize, plan ahead, understand, abstract. And you can imagine this can make your life difficult," said Vassili Koliatsos.

Koliatsos, a pathologist and neurologist who led the study, says the specific honeycombed pattern of these damages and their concentration near blood vessels suggest that the force of a powerful explosion squeezes the blood in the soldiers' chest and pushes it into the brain.

“Because there's a pulse of over-pressure wave that happens like this, the brain also swells like this. And when the brain swells, it pushes against some of the fixed elements inside the skull," he said.

Koliatsos says, if there is a neurological basis for these damages, doctors may start thinking of prescribing different medications to the veterans suffering from post-traumatic stress disorders, and military planners may be able to help the survivors' by improving the soldier's chest protection.