Although many of us are now city-dwellers, living technologically advanced lives, for the vast majority of our time on Earth we did not live this way. For millions of years, humans lived as hunter-gatherers in small tribal groups. These people lived in villages surrounded by barriers to keep all of the hungry animals and enemy tribes out. Being human was a highly dangerous existence, which is one reason our ancestors didn’t live that long.

Those that did survive had extremely sensitive threat systems in their brains, which were constantly scanning for danger – hungry lions, venomous snakes or club-wielding enemies. And when the amygdala, the part of the brain that scans for threat, detected something worrying, it triggered the fight-flight-freeze response, our three main options for survival when we are under threat.

Now although you may be reading this on your smartphone or laptop, and presumably (hopefully!) you are not surrounded by hungry wild animals, your brain hasn’t changed a great deal since your ancestors lived on the savannah. And that threat system hasn’t changed at all – in fact, your threat system is the same as that of the cute deer in the photo, cats, wolves, lizards, even dinosaurs, because it works so well that evolution didn’t need to change it.

When your brain says fight

If you experienced trauma as a child, or had a single traumatic incident as an adult, unfortunately the threat system in your brain will be highly oversensitive and your amygdala will be on red alert, over-reacting to even minor stressors. This is one reason that trauma survivors are often hypervigilant, reacting to fairly neutral or benign situations as if their life is in danger. That’s because it feels as if your life is in danger, so you go into emergency-action mode to survive.

If your threat system decides a fight response is the best way to survive that threat, it gives you a big jolt of anger to warn you that something is wrong and it’s time to act. At the same time, your breathing changes to take in more oxygen and your heart speeds up to pump oxygenated blood to your major muscles. That, plus the adrenaline and cortisol in your bloodstream, gives you strength and energy to fight (or flee, which involves a similar mobilisation in your body). You fight off the hungry wolf or enemy tribesman, the threat passes and you calm down.

…Or flee

Unfortunately, if you are a trauma survivor, one of the common consequences is that your sympathetic nervous system (the ‘go’ system that helps us be energised or active) stays jammed on. So even when the threat has passed, you still feel agitated and unsafe. If you feel anxious and like you want to run, escape or avoid the stressful situation, your flight response has been triggered.

This happens when your threat system decides that running is a better option than fighting, so you get a big jolt of anxiety, roughly the same mobilising process in your body as with a fight response, and you run. This is why avoidance is inextricably linked with anxiety, because avoiding the party, meeting, first date, etc is a form of running away from it.

…Or freeze

If your brain decides that you can’t fight or run from the threat, especially if you feel trapped or helpless, it activates the freeze response. Imagine you are a small child, with an angry, shouty parent – you can’t fight them, because you’re too small. And you can’t run, because there’s nowhere to go. So you freeze, which might feel like being stuck or paralysed, your mind going blank, or feeling spacey, numb or empty inside.

This is a common reaction when people are in a single-incident trauma like a mugging, car crash or industrial accident. We can get so overwhelmed that we freeze, even though we know we should fight the mugger or run out of the factory. It’s a horrible feeling – and a common factor in post-traumatic stress disorder (PTSD), because people beat themselves up about not taking action, which interrupts the normal post-traumatic healing process.

I will write in more detail about each of these responses, how they link to trauma, and what we can do to help ourselves overcome them, in future posts. But for now, I hope that gives you some understanding of what’s happening in your brain, body and nervous system when you respond in one of these three ways. As I always tell my clients, knowledge is power – it’s the first step in understanding and healing from your trauma.

Warm wishes,

Dan