Fearless Woman Lacks Key Part of Brain

摘要

"SM" is a bit of an emotional anomaly. The 44-year-old mother, given those initials to preserve her anonymity, is pretty much fearless-and now scientists think they've figured out why. SM has interested researchers because a rare genetic condition called Urbach-Wiethe disease destroyed her amygdala, a pair of almond-shaped clusters of neurons in the brain that play a role in fear and anxiety. Justin Feinstein, a graduate student in clinical psychology at the University of Iowa in Iowa City, and colleagues wanted to test whether SM could experience fear. They recorded her reaction to snakes and spiders, horror films, and a trip to a notoriously scary haunted house.