"Our study suggests that there may be long-term neural correlates of trauma exposure, even in people who have looked resilient," said lead author Barbara Ganzel, Cornell M.S. '99, Ph.D. '02, a postdoctoral researcher in human development at Cornell. "Up until now, there has been very little evidence of that."
Using functional magnetic resonance imaging to see how people's brains responded to photographs of fearful versus calm faces, the scans of 11 people who were within 1.5 miles of the World Trade Center on Sept. 11, 2001, were compared with those who were living more than 200 miles away at the time; none of the subjects had psychiatric disorders.
"We know that looking at fearful faces in normal adults tends to activate the amygdalae relative to looking at neutral faces," said Ganzel. "So we were looking to see if people who have had a very bad experience would have more response to this relatively mild everyday stimulus."
Indeed, the amygdalae of those who were close to the twin towers were significantly more activated than that of others, even when other factors were controlled for in the analysis.
"People who had experienced traumas that left them with more lingering symptoms were the ones who had higher activity in their fear centers," said Temple. "We think that the World Trade Center experience was traumatic enough that it left them with hyperactive amygdalae."