It’s the lizard brain.
Evolution works likes a bad remodel of an old house. Instead of starting fresh with a new design, one change gets aggregated on another, in small steps, so that each stop of evolution looks almost identical to the one before. It’s why we still have our appendixes and gall bladders, and why our eyes work the way they do
And deep inside our big modern brains, the ones that make us thinking beings, the older parts of the brain still exists, sitting and pulling our strings without us knowing it. So right under the part of the brain that memorizes poetry and plays piano, is the part of the brain that wants to scuttle away from loud noises and hide under a rock.
There are also patterns learned when we are young. Maybe we were told we liked vanilla ice cream better than chocolate (my mom did this to me) so often we still believe it. Maybe we learned not to talk about what goes on at home. Or maybe we were taught to like hot peppers, or garlic, or dislike salt. Or show love by nagging.
THOSE patterns can drive us just as hard. They feel as basic as fear of heights, fear of loud noises, hunger. And they are, mostly, unconscious. But just as we climb trees and mountains, go to rock concerts, and become anorexic (or just stick to a Weight Watchers eating plan or any other diet) we can beat those patterns. If we know what they are.
Knowing mistaken patterns, from instincts, from functional thoughts takes a bit of skill, and detachment.
Which is uncomfortable.