Known as the brain's "fear center," the deep-seated, almond-shaped amygdala helps direct intense emotional responses. New work from the National Institute of Mental Health unveils a genetic variation as a key factor in responses to fear.
Using functional magnetic resonance imaging scans, the researchers mapped amygdala responses to frightening faces. They found that, of the 28 volunteers, those who had inherited certain variations in the gene for the serotonin-transporter molecule experienced more amygdala activity—more fear, in other words. This inherited reaction to danger may be a boon or bane, said Daniel Weinberger, MD. It "can place us at risk for an anxiety disorder, or it may be an adaptive, positive attribute, such as increased vigilance, depending on the circumstance."
Vastag B. Fear in the Amygdala. JAMA. 2002;288(7):823. doi:10.1001/jama.288.7.823-JHA20008-4-1