" But suppose the stressor is one that your brain determines you can’t survive by escaping and you can’t survive by conquering—you feel the teeth of the lion bite into you from behind. This is when you get the brakes stress response—the parasympathetic nervous system, the “STOP!” activated by the most extreme distress. Your body shuts down; you may even experience “tonic immobility,” where you can’t move, or can move only sluggishly. Animals in the wild freeze and fall to the ground as a last-ditch effort to convince a predator they’re already dead; Stephen Porges has hypothesized that freeze is a stress response that facilitates a painless death.1 "

― Emily Nagoski , Come as You Are: The Surprising New Science that Will Transform Your Sex Life