Kernel of Fear

How can just the smoke make a veteran relive all the horrors of combat in hallucinatory detail? The answer lies in the Amygdala, a tiny brain structure in which nerve pathways shackle innocent stimuli to memories of unbearable terror.

By Mark Caldwell
Jun 1, 1995 5:00 AMNov 12, 2019 6:27 AM

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Fear may not be one of the more pleasurable emotions, but it is an effective survival tool. Sheer terror efficiently propels you away from the predator that wants to eat you; anxiety, fear’s milder (if more gnawing), civilized form, chivies you into meeting the deadline set by a scary superior. In either case, the reward you get for enduring the cold sweat and the pounding heartbeat is that you live on to gather up another lunch or meet another deadline.

Unfortunately, fear sometimes floods out beyond the channels where it’s useful. Take the experience of the Gunny, as he asked to be identified: the Gunny was stationed with the Marines in Vietnam from 1969 to 1971. He is a compact, powerfully built man with a threateningly shaved head but a disconcertingly kind gaze and a gentle voice. I go into deep flashbacks, he says. It’s like I’m right there again--the sounds, the smells, the screaming. It’s almost like a blackout; the present doesn’t exist. It can be snowing and I sweat like I’m in the jungle. So debilitating did these attacks become that one day in 1987 the Gunny walked away from his Pittsburgh post office job and spent the next three years in the backcountry of Pennsylvania--emerging only when he found himself stalking hunters in the woods. Scared by this silently rising pressure of violence, he forced himself back into civilization and began treatment.

The gunny suffers from post-traumatic stress disorder, a pathological form of anxiety. The syndrome typically begins with a trauma beyond the range of normal human experience--combat, say, or a disaster like the Kobe earthquake or the World Trade Center bombing. Some people emerge unscarred by such experiences, but PTSD patients are uncontrollably and often permanently affected. Small irritants like a thunderclap can set in motion tidal waves of panic, even full-color flashbacks, during which sufferers relive horrors that may have vanished from their conscious memories.

The war in Vietnam spawned a near epidemic of PTSD. In fact, U.S. soldiers’ experiences there gave rise to what’s now regarded as the classic form of the disorder. Vets like the Gunny, who is undergoing treatment at the National Center for PTSD (a unit of the Veterans Affairs Medical Center), in West Haven, Connecticut, are far from unusual. I can numb out for hours, not thinking of anything, echoes George K., another patient at the center. But then something will remind me and take me back--the odor of a certain kind of wood burning, or even of a plant, since I live in Florida and the vegetation is a lot like Vietnam’s.

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