Scientists have discovered the part of the human brain responsible for fearing unfamiliar things, according to the Daily Mail. Researchers point to the amygdala, a small nut-shaped area of the brain connected to depression and autism, among other things. This group of neurons is thought to be at work whenever we perceive something unknown to us to be a direct threat, like a wild animal or an attacker with a weapon. However, it is not clear what the amygdala's role is when dealing with a more subjective danger, one that isn't quite obviously malevolent.

In the study — by Laura Harrison and Ralph Adolphs and published in the Journal of Psychological Science — people were asked to determine whether the facial features of distorted images and normal images were either "trustworthy or threatening," according to DetroitNewsTime. The researchers looked at people's answers from two groups — one with amygdala damage and the other without (the control group).

Those with amygdala damage seemed more readily accepting of those whom the control group deemed threatening.

The science in understanding the amygdala could prove useful in helping to treat those with anxiety disorder, another disorder the amygdala is said to be tied to.