Contemporary science has refined the old “fight or flight” concept — the idea that those are the two hard-wired options when in mortal danger — to the updated “freeze, flee, fight.” While “freeze, flee, fight” is superficially similar to “run, hide, fight,” the two expressions make fundamentally different assumptions about how and why we do what we do, when in danger.

Why do we freeze? It’s part of a predatory defense system that is wired to keep the organism alive. Not only do we do it, but so do other mammals and other vertebrates. Even invertebrates — like flies — freeze. If you are freezing, you are less likely to be detected if the predator is far away, and if the predator is close by, you can postpone the attack (movement by the prey is a trigger for attack).

The freezing reaction is accompanied by a hormonal surge that helps mobilize your energy and focus your attention. While the hormonal and other physiological responses that accompany freezing are there for good reason, in highly stressful situations the secretions can be excessive and create impediments to making informed choices.

A vivid example of freezing was captured in a video of the Centennial Olympic Park bombing during the 1996 Summer Olympics in Atlanta. After the bomb went off, many people froze. Then, some began to try to escape (run), while others were slower on the uptake.

This variation in response is typical. Sometimes freezing is brief and sometimes it persists. This can reflect the particular situation you are in, but also your individual predisposition. Some people naturally have the ability to think through a stressful situation, or to even be motivated by it, and will more readily run, hide or fight as required. But for others, additional help is needed.