Of course, you don’t actually want the stress response system to be too reactive. If you were constantly in fight or flight mode, constantly stressed, it could actually have long-term effects on your neurochemistry, leading to chronic anxiety, depression, and, well, more sleeplessness. Even so, it seems like a good idea to sometimes be on high alert when dealing with stressful situations.

But that’s not what my body did. My body shut down.

I asked around, and found out that many others experience the same thing. For example, Dawn, a family counselor in Columbus, Ohio, told me that her husband Brad often “starts yawning in the middle of heated discussions, and will even lie down and go right to sleep.” One time their toddler son fell down the stairs (he was fine), and Brad left the room and went to bed. Brad has had this kind of stress response for all 24 years of their relationship; Dawn says she’s used to it by now.

Even though dozens of people told me similar stories, I began to wonder what was wrong with us—what was wrong with me. Why was my body, in the face of conflict, simply acquiescing? Where was the fight in me?

There’s a concept in psychology called “learned helplessness” used to explain certain aspects of depression and anxiety. It’s fairly old, having been first recognized and codified in the 1970s, but has remained largely relevant and accepted within the field. The name (mostly) explains it all: If, at a very early stage in development, a living thing comes to understand that it is helpless in the face of the world’s forces, it will continue to perceive a lack of control, and therefore actually become helpless, no matter if the context changes.

In the early studies, dogs were divided into two groups: The first half were subjected to electric shocks, but were given a way to stop the shocks (they just had to figure it out themselves). The second group of dogs received shocks but had no way to avoid, escape, or stop them. The experience, sadly, had long-term effects on the animals. When faced with stressful environments later on in life, the first group of dogs did whatever they could to try to deal with it; the second group simply gave up. They had been conditioned to respond to stress with acquiescence.

This type of learned helplessness isn’t limited to animals; many of the adults I spoke with all mentioned childhood anxiety stemming from uncontrollable situations.

“When I hit high school and stress levels became higher in my life (messy divorce between my parents and lots of moving), I began escaping into sleep,” says LeAnna, a 25-year-old from Washington state. “As an adult, I still have ‘go to sleep’ impulses whenever I feel overwhelmed.” Daniel, from Baltimore told me that “whenever there was any kind of ‘family strife’ I would just go to my room and sleep.” Daniel is now 51, and starts yawning any time he encounters a stressful situation.