Learning more about Aaron Alexis' past, and mental health issues

WASHINGTON, D.C. (WITI) -- One day after the mass shooting in Washington, D.C., we are learning more about the alleged gunman in the tragic Navy Yard shooting. New reports suggest Aaron Alexis may have suffered from post-traumatic stress disorder. There are also reports that he was battling other mental health issues.

12 people were killed by gunfire at the Washington Navy Yard on Monday, September 16th. The alleged shooter, 34-year-old Alexis is a Navy reservist who was recently discharged following a pattern of misconduct.

"With any of these disorders, the individual influences how the disorder manifests as well. The ones we hear about tend to be this terrible cases of violence but there are lots of people suffering from mental illness who aren't displaying that type of behavior," Dr. Paul Gasser said.

Dr. Gasser is a neuroscientist from Marquette University who studies the effects of stress on brain function and behavior -- specifically PTSD.

"Mental illness is not always somebody who goes off the handle and shoots people. Mental illness is a broad spectrum of very difficult disorders," Dr. Gasser said.

But were there warning signs?

Prior to Monday's rampage, Alexis had run-ins with the law, including an incident in 2004, which was described as an anger-fueled blackout. In 2010, he was arrested for firing a gun in his apartment.

"It's when you're alone and you don't have help and you feel the world is against you. Then, there's nothing left to do," Dr. Murray Bernstein said.

Dr. Bernstein is the Clinical Director of Veterans Quest that specializes in healing those affected by PTSD. He says while we don't know exactly what triggered Monday's violence, one thing is certain in all cases of mental illness.

"You need support systems and if you're in the military you need other veterans to talk to that will be there that have been there and can communicate," Dr. Bernstein said.

Reports say the terrorist attacks on September 11th triggered Alexis to start a pattern of erratic behavior. There were also reports he tried to get help at a VA facility but to what extent is unknown.