Fearless woman's brain reveals key to phobias

The case of a literally fearless woman — rendered so after brain damage — has helped scientists confirm that a part of the brain structure regulating emotions is the key to human and animal phobia.

Scientists had to prevent SM, a patient unable to experience fear due to damage to her brain, from touching a tarantula in a pet store. The 44-year-old mother of three, referred to in the journal Current Biology as SM, has a rare psychological impairment due to a genetic disease called lipoid proteinosis that left holes where her amygdala — the brain’s danger detector — would normally reside.

The patient felt excitement, but never fear in a series of threatening scenarios monitored by researchers with the University of Iowa, led by Justin Feinstein, a clinical neuropsychologist.

The American woman was taken to a pet store to interact with snakes and spiders, where she was reported to have exclaimed, “This is so cool!” while rubbing a snake’s scales and touching its tongue.

One night in 1995, a strange man leapt from a park bench and pressed a knife to her throat, threatening to cut her.

“If you’re going to kill me, you’re going to have to go through my God’s angels first,” she replied, looking at him coolly. She then walked away and returned to the park the next day.


Fearless woman's brain reveals key to phobias