45 volunteers have signed up to help Texas A&M University test an app which might help veterans suffering from PTSD.
It monitors the vet's heart rate to provide an early warning that a PTSD attack is coming.
The high-tech system then tells the vet what's needed to get through it.
"It intervenes by asking a question: 'How do you feel?' Based on that answer, it connects them to some sort of support system," Farzan Sasangohar of Texas A&M University said.
Among other things, the app could walk the vet through breathing exercises, or connect the veteran to a help line.
Between 10% and 20% of veterans from the Iraq and Afghanistan wars have a PTSD episode in any given year.