Just like a muscle, the more a brain system like the stress response network gets “exercised,” the more it changes and the more risk there is of altered functioning. At the same time, the less the cortical regions, which usually control and modulate stress, are used, the smaller and weaker they get. Exposing a person to chronic fear and stress is like weakening the braking power of a car while adding a more powerful engine: you’re altering the safety mechanisms that keep the “machine” from going dangerously out of control.
