PALO ALTO, CALIF.--In the midst of disaster, people sometimes react with uncanny calm. It's a survival mechanism: In a fire or flood, for instance, a cool head helps people gather their children, pets, and cherished possessions before the emotional impact of losing their home leaves them helpless.

But according to a new study, those who are too cool in the face of calamity run a much higher risk of developing disturbing psychological symptoms later on.

Within a month of the 1991 Oakland hills firestorm, in which 3,135 homes were destroyed and 24 people died, Stanford University psychologist Cheryl Koopman questioned 154 survivors. Koopman asked whether they had experienced strong feelings of confusion, unreality, timelessness, or emotional detachment during and right after the fire--all symptoms of a psychological state called dissociation. Seven months later, she and her colleagues asked the fire victims whether they had experienced such signs of posttraumatic stress as flashbacks, nightmares, extreme anger or anxiety, and an unwilling preoccupation with the disaster.

Some dissociation is normal in times of extreme stress, and, in fact, Koopman found that 78 percent of the survivors described at least one symptom of unnatural calm during the fire. But it can be dangerous. Seventeen percent of fire victims who scored high on the dissociation scale tried to break through police barricades to go back into the fire, compared with 8 percent of people with no such symptoms. And those who experienced the strongest dissociative symptoms were 20 times more likely than those who expressed anxiety to develop posttraumatic stress symptoms.

Dissociation is a defense that can work too well, says Koopman. To avoid long-term psychological stress, disaster victims should let their feelings out, she says. "It helps to grieve."

By Laura Fraser and Michael Mason

Tragedy struck the USS Iowa naval ship on April 19, 1989, as it sailed north of Puerto Rico. A gun turret exploded, killing all 47 men working within its steel-encased walls. At Dover Air Force Base in Delaware, 71 members of the local community--mostly enlisted men in the U.S. Air Force--volunteered to help mortuary officials in grueling duties that included identifying the dead sailors, conducting autopsies, and sorting personal belongings.

Over the next 13 months, volunteers who had felt that one or more victims reminded them of a friend were particularly likely to exhibit a severe trauma reaction known as post-traumatic stress disorder (PTSD) or other signs of mental turmoil, according to a study in the March American Journal of Psychiatry. PTSD symptoms include re-experiencing a traumatic event, avoiding reminders of it, emotional detachment, and heightened physiological arousal.

Disaster workers who had personally identified with the dead (noting, "It could have been me") or who had thought of them in regard to a family member ("It could have been my son") experienced fewer subsequent trauma-related problems, about the same number as their counterparts who had not identified in any way with victims, reports a team led by psychiatrist Robert J. Ursano of the Uniformed Services University of the Health Sciences in Bethesda, Md.

The researchers assessed 54 volunteers a month after the disaster. Of that group, 41 were contacted 4 months later and 44 were questioned about 13 months after the fatal explosion.

Nearly three-quarters of the original 54 volunteers said that they had identified with victims as friends, family, self, or in more than one of those ways. Aside from their elevated PTSD rate, workers who had identified with victims as friends also cited higher levels of anger, anxiety, depression, and physical complaints of undetermined cause.

Those who had identified with the dead as friends--and later encountered more trauma-related problems--averaged 25 years of age, about 5 years younger than the volunteers who did not associate friends with victims.

Reasons for the link between identification with the deceased as a friend and ensuing psychiatric symptoms are unclear. Further work needs to examine whether this type of identification by itself triggers trauma-related problems or instead reflects deeper concerns, such as unresolved grief for friends' deaths or the loss of past friendships.

By Bruce Bower