Scientists have discovered a rare brain disorder that potentially eliminates all known notions of fear. The Urbach-Wiethe disease destroys the amygdala, a part of the brain strongly implied to be associated with fear processing. University of Bielefeld neurologists confirmed this after testing a series of fear-inducing activities on a middle-aged woman, codenamed “SM,” afflicted with the disease.
Feinstein and his colleagues sifted through SM’s past, looking for instances when she should have been scared. SM said she never felt fear, even when threatened with a knife or a gun. The researchers gave SM an electronic diary that she carried for three months to record her emotional state. Fear didn’t make an appearance in the list of emotions. On a battery of questionnaires, SM wrote that she wasn’t afraid of public speaking, death, her heart beating too fast or being judged negatively in a social setting.
Next, the researchers did their best to scare SM. They showed her clips from The Blair Witch Project,The Shining and Silence of the Lambs: She was interested, but not afraid. The Waverly Hills Sanatorium Haunted House in Kentucky didn’t faze her. Instead of screaming, she laughed and poked one of the monsters in the head. The team took her to an exotic pet store with poisonous snakes and spiders. SM claimed to dislike the animals, but when she saw them she was overcome with curiosity, repeatedly asking to touch the snakes.
“What that suggests to us is that perhaps the amygdala is acting at a very instinctual, unconscious level,” says Feinstein. “Without this area, instead of just losing your interest in things, you do the very thing that’s opposite. She tends to approach the very things she should be avoiding.”