"I froze." Those words, or something close to them, are frequently heard from rape victims after the assault, writes Jen Percy in the New York Times Magazine. They often lead to judgments from investigators and even loved ones. You didn't fight back? Victims might similarly judge themselves. I didn't fight back? But Percy explains that the response is so common that it's time to both destigmatize and better understand the phenomenon known formally as "tonic immobility." It refers to an evolutionary behavior not just in humans but throughout the animal kingdom with one purpose—to help us stay alive. "Tonic immobility is a survival strategy that has been identified across many classes of animals—insects, fish, reptiles, birds, mammals—and draws its evolutionary power from the fact that many predators seem hard-wired to lose interest in dead prey," writes Percy.
It explains why so many rape victims can't explain to investigators their response after an attack. "Under stress, your brain disconnects from its more recently evolved circuits and strengthens many of the primitive circuits, and then these unconscious reflexes that are very ancient kick in," says Yale neuroscientist Amy Arnsten. Percy also writes about a growing push to educate both the medical and criminal justice communities about the issue. Mike Milnor, a former police officer who now helps teach a class on the subject to investigators, puts it this way: "I can't tell you the number of times that I've had these tough, seasoned, burly cops coming up to me with tears in their eyes, saying how they're thinking about the victims that they treated poorly, not out of malice, but out of ignorance." (The full story is an important, if difficult, read.)