On this September 11th, we recommend this Scientific American article that discusses how people experience trauma and what works best to help them in their recovery.

Like many other major disasters, 9/11 brought with it a host of psychological repercussions, one of the most severe of which has been post-traumatic stress disorder. PTSD is characterized by trouble sleeping, difficulty controlling anger, losing interest in activities, flashbacks, emotional numbness and/or other symptoms. If not treated, it can be debilitating.

But these reactions are not uncommon after a major disaster—and teasing apart post-9/11 disorders has been tricky for psychologists and researchers. “We tend to use the terminology of PTSD very loosely. A lot of people will have traumatic reactions but not necessarily PTSD,” says Priscilla Dass-Brailsford of Georgetown University Medical Center’s psychiatry department.

Researchers have been poring over the piecemeal collection of studies conducted over the past decade on the conditions of people after the attacks—how they felt and how well various treatments, and the passage of time, have helped them overcome mental afflictions. And from the literature, we are learning that old styles of early intervention, such as debriefing sessions, are not as effective as once thought—and that more often than not, people are incredibly resilient and can recover on their own and should be given the opportunity to do so.

“Research on 9/11-related PTSD has challenged the ways in which mental health researchers assess exposure to trauma,” Yuval Neria, of Columbia University’s psychiatry and epidemiology departments, and his colleagues wrote in a new paperpublished in the September issue of American Psychologist. Those in the mental health field have also borrowed research from other traumatic events to better understand the psychological wounds inflicted by the terrorist attacks. “Despite the fact that the exposure is different, the symptoms and problems are more similar than some people think,” Neria says of PTSD sufferers from natural disasters or combat.