But what if PTSD could have been prevented in the first place?

Scientists have done something similar in traumatized mice. Days after a harrowing experience being restrained on wooden boards, they were given a drug that triggers a brain receptor thought to be involved in how mice — and people — respond to fear.

“We prevented PTSD-like symptoms,” said Emory University neuroscientist Raul Andero Gali, lead author of a study published Wednesday in the journal Science Translational Medicine.

The study raises the possibility that similar drugs could one day be given to people after combat, car accidents or other types of trauma. The prospects for developing such a treatment are very good, said Sheena Josselyn, a neuroscientist at the University of Toronto who was not involved in the research.