From the New York Times, I'm Sabrina Taverniese, and this is the Daily.

A mass shooting last fall by an army reservist in Maine prompted my colleague

Dave Phillips to search for answers about whether the soldier's service could have

been a factor.

Today, the surprising answer Dave found,

and how it may change our understanding

of the effects of modern warfare on the human brain.

It's Wednesday, March 13th. So Dave you've been working on a series of stories on injuries to soldiers in the

U.S. military and last week there was kind of a sudden and unexpected discovery related to that

reporting you'd been doing.

Tell me about it.

So what I've been looking into for a couple months was the idea that soldiers can be injured just by firing

their own weapons by standing next to the blast of a mortar or launching a rocket

from a shoulder-fired rocket launcher, some of these big heavy weapons.

The blast wave is strong enough to really injure their brains.

And I'd been working on that over a couple of months because it's very new and there's a lot of uncertain stuff and I was still working on it in October when I got a call from the New York Times National Desk and, hey, there's been a mass shooting in Maine.

We need your help.

The suspect was in the military.

So I dropped everything and got on it.

Right, because you're the guy who covers military affairs, so they call you.

Right, and the situation was that there's a 40-year-old man in Maine named Robert Card.

He'd been a Sergeant First Class in the Army Reserves for almost 20 years and he

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