3) Events can sometimes be so traumatic that they may change the function of the O brainstem
O amygdala
O occipital axis
O REM centers

Amygdala

Explanation:

The Amygdala is the part of the brain that processes emotions such that they are defined and then remembered. It also attaches these emotions to certain memories so that similar events can be reacted to in the same way.

When a human being is exposed to something truly traumatic, the amygdala could change the way it functions. It could become overreactive such that the person begins to view both the world and themselves in a negative light.