" Once, unfortunately, in a crisis situation (as the Greek poet Archilochus pointed out so long ago) we don't rise to the level of our expectations, we fall to the level of our training. Once again, the issue is fear. The more fear in the equation, the fewer options at our disposal. In times of strife, the brain limits our choices to speed up our reaction times. The extreme example being, fight or flight, where the situation is so dire, that the brain gives us only potential actions. Freezing is the third, yet the same thing happens to a lesser degree under any high stress conditions. And the responses we fall back upon under duress, are the ones we fully automatized: those habitual patterns we've executed over and over again. "

― Steven Kotler , The Art of Impossible: A Peak Performance Primer