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Michel Catalano was expecting a delivery last Friday morning at his printing plant in Dammartin-en-Goële, a town to the northeast of Paris, when he heard the bell ring. What the printing company’s chief executive did not expect, he later told The Telegraph, was to see an armed man standing right outside:

In front of my business there is a window, and at the bottom of it I saw that there was a man with a rocket launcher and a Kalashnikov. I saw immediately that we were in a dangerous situation. So I came back and went to my employee, Lilian, to tell him to hide. I turned back towards [the gunmen], knowing that the both of us could not hide. I swear I thought that was the end, that it was all over, finished.

Catalano went on to describe how the Kouachi brothers—the two men who killed 12 people at the offices of Charlie Hebdo last Wednesday—entered his plant without aggression, telling him not to worry. Catalano ended up offering them coffee and tended to one of the brother’s wounds. Ultimately, he spent an hour with his captors, while his colleague Lilian texted the police details of the scene inside the plant.

“I was never scared, because I had only one idea in my head,” Catalano told the AP. “‘They should not go to the end (of the hallway) to see Lilian, that’s all.’ That’s what kept me calm.”

The businessman’s story of survival was not the only one to grab the world’s attention in recent weeks. On the same day Catalano was released and the Kouachi brothers killed, more than a dozen people were held hostage in a kosher supermarket in Paris by a man named Amedy Coulibaly, who fatally shot four and had lined the store with explosives. (Many of the hostages hid in a dark basement while the situation was ongoing, for about four hours.) Just a month ago, in Sydney, a gunman claiming allegiance to the Islamic State held 18 people hostage in a Lindt chocolate café for 16 hours. Dramatic videos showed several of the hostages escaping throughout the afternoon, before police stormed the site.

These experiences are scary enough to read about and watch, but what are they like to live through? Are hostages irrevocably damaged, or can they recover and return to their normal lives?

Contrary to what one might expect, research indicates that not all survivors of terrorism and hostage crises develop mental-health conditions like anxiety, depression, or post-traumatic stress disorder. Many return to normalcy with time, and some may actually fare worse if they go through immediate mental-health interventions. Still, in the short-term, survivors are likely to experience traumatic flashbacks and seek to avoid triggers.

“Let’s say those people in Paris stop going to the grocery store, because that’s where [the attack] happened, or to Jewish gatherings, because [the attack] targeted Jews, and they don’t want to talk to anybody about it,” said Anne Speckhard, an adjunct associate professor of psychiatry at Georgetown University Medical School. “That’s very likely, and completely normal after a traumatic incident.”

Speckhard, who is the author of Talking to Terrorists and an expert on PTSD, added that it is important to normalize symptoms of trauma for survivors, so that they don’t develop uncontrollable fear, among other problems. But, she admitted, clinicians disagree on what form early intervention should take; for example, some believe it is ineffective or harmful to perform immediate psychological debriefing with victims, because the psychic and physical wounds are still too fresh. Advocating a “middle line,” Speckhard said it’s useful to inform victims of the various ways in which acute stress may manifest itself.

Of course, not all victims of violence respond to and cope with it in the same way. A 2009 review of hostage-taking literature identified three types of psychological harms to survivors: cognitive, emotional, and social. These included impaired memory, intrusive flashbacks, hypervigilance, anxiety, anger, depression, guilt, and withdrawal from others. Certain victims, the review noted, will even deny that the hostage-taking has occurred, as a means of delaying psychic pain and having to radically adjust.

Simon Wessely, a psychologist at King’s College London, said the extent to which people are traumatized by an event results from a mixture of vulnerability factors, like genetics and personality, and the nature of the event itself. For example, civilians involved in a terrorist incident are more likely to develop psychological problems than are certain professionals who  may be trained in how to respond.

Perhaps the most widely floated terms regarding hostage mental health, however, are PTSD and Stockholm syndrome. The former describes an anxiety disorder that may arise after a person suffers a harrowing event like sexual assault, military combat, grave injury, or threat of imminent death. According to the American Psychiatric Association’s DSM-5 manual, a diagnosis of PTSD requires a series of criteria to be met, including recurrent intrusion of the traumatic event, avoidance of triggers, negative mood changes, sleep disturbance, and duration of symptoms for more than one month.

PTSD is common for survivors of hostage situations and terrorist attacks, with one study from 2005 finding that the latter group had higher rates of PTSD than did survivors of motor-vehicle accidents (37.8 vs. 18.7 percent). Likewise, a 2002 review in the New England Journal of Medicine predicted that, based on PTSD rates among survivors of the 1995 Oklahoma City bombing, approximately 35 percent of those who were directly exposed to the September 11 attacks would develop the disorder. A decade later, The New York Times reported that at least 10,000 survivors of the World Trade Center attack had been found to have had PTSD. Although estimates of how many people were in the Twin Towers on the morning of September 11 vary, a 2009 study using various data put that number at roughly 16,000.

The logic of Stockholm syndrome, or when captives express sympathy, trust, and positive feelings towards their captors, is a little more difficult to understand. (It is also known as “capture-bonding.”)

“All of us, when we’re threatened, activate attachment behaviors, thinking ‘Who can help me now?’” Speckhard explained. “You might think of your parents or your spouse. Hostages do the same thing, and the only people to attach to in their situation are often the people who are harming them.”

In other words, Stockholm syndrome is about power: Who has the power to make the pain and fear go away? Speckhard pointed to Patty Hearst as the “poster child” of the phenomenon; in 1974, the then-19-year-old granddaughter of publisher William Randolph Hearst was abducted by the Symbionese Liberation Army and eventually began to identify with her captors. She committed a bank robbery, fled the police, and was sentenced to seven years in prison. (President Jimmy Carter commuted Hearst’s sentence to 22 months, and she was pardoned by President Bill Clinton in 2001.)

Stockholm syndrome takes time to set in, so it’s unlikely that many—if any—of the recent hostage victims in Sydney and Paris will significantly express it. Yet, the attachment created between hostage and captor may cause temporary feelings of confusion, guilt, and embarrassment among survivors. “What underpins this bonding, for different individuals in different crises, has yet to be determined,” the 2009 review of hostage literature by the Royal Society of Medicine states. “It is also unclear to what extent the apparent motives of the perpetrators influences the bonding between captor and captive (although it can be difficult to identify the true motives of, for example, terrorists who take hostages).”

For many survivors, time may prove to be the best method to cope with being captured. “Ordinary people are tougher than we sometimes give them credit for being,” Wessely wrote after the July 2005 bombings in that city. “And this should come as no surprise … We must be careful to avoid shifting from the language of courage, resilience, and well-earned pride into the language of trauma and victimhood.” The word resilience has important connotations in psychology, referring to how humans can ‘bounce back’ from negative experiences. Various studies have found that focusing on daily living and developing a narrative for traumatic events—telling the story of what happened—can help. Other strategies for hostage recovery include distractions like reading, and discipline like daily exercise.

But for those more seriously affected by the incident, therapy and medication may be key interventions.

“There are some people who walk away from trauma and do fine, while others will develop a full case of PTSD,” Speckhard said. “Part of it is training, experience, coming out on the other end intact; part of it’s genetic, too. Whatever the case, you’ll do much better if you have a strong support system around you.”

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