amygdala

there is a part in human brain that's called amygdala, its function is to instill fear in human so as to prevent them from any harm, but the dysfunctionality of this organ part in one's brain caused somewhat peculiar result.there is a woman who had her amygdala not functioning properly and thus made her fearless of any perilous events that came in contact with her.now at least we know why some people are so fearful and some of them are fearless.it's all located in their brain and amygdala played a bigger role in causing it.

perihal:

"Instead, she held a snake, pet its scales and touched its tongue. She enjoyed intensely scary horror movies like they were thrilling but fun roller coaster rides. And she revealed through her stories and her diary a lifetime of behaviors that would strike most people as odd and qualify, by all standards, as dangerous."
- The No-Fear Woman (And What Her Brain Reveals) : Discovery News (lihat di Google Wikipinggir)