Imagine the following scenario: You are driving home from work at night, you pull into your driveway, and no lights are on at your house. It’s darker out than you’d expect, and as you walk to your front door, you hear something rustling in the bushes by the front door. In a moment, your whole demeanor changes. You don’t know if it’s the neighbor’s cat or something more sinister, but you’re ready for anything. That change is your body’s alarm system, which is commonly known as your “fight or flight response,” and it is one of the body’s oldest and most valuable survival tools. But, what exactly is it and do we still need it today?

What is it?

The fight-flight response is a common term for what all people experience when specific parts of the brain and body have been activated. When you perceive a possible threat in your environment, a part of the primitive, emotional center of your brain, the hypothalamus, triggers a neurochemical sequence that activates your sympathetic nervous system. As the sympathetic nervous system engages, your kidneys release two chemicals, adrenaline and noradrenaline. These chemicals initiate a sequence of events within your body that prepare you either to flee quickly from danger or to stay and fight in a way that causes as little harm to yourself as possible.

In layman’s terms, when you feel threatened, your body’s alarm system sets things in motion to try and keep you safe, either by running away or fighting. If we think back to our caveman ancestors, there were times when they were exposed to large, dangerous predators and needed to react quickly in order to survive- leaving no time for slow, rational thinking. This is exactly what the fight or flight response allows for, and a part of what has allowed our species to survive.

This response still helps to protect us today, even if the threats we face are slightly different than they were for our ancestors. And, today we can experience this slightly differently than our ancestors did! People can experience this either as panic attacks or as a general increase in physical arousal with a number of specific physical symptoms.

The third option: Freeze response

While fight and flight get a lot of attention, there is also a third response that humans can experience in the face of danger – the freeze response. When having a freeze response, people do not move and may feel disconnected from their bodies or from reality. Freezing in the face of danger can seem completely counter-intuitive, and many people who experience this response blame themselves or feel tremendous shame for responding in this way. The reality is however that the freeze is actually very adaptive in some situations!

The freeze response is useful when a person is faced with a threat that you cannot fight off or outrun. Fighting or fleeing in this situation would likely only result in further harm to you while freezing may actually give you the best chance of escaping the situation unscathed. And, in case you don’t get away without a fight, while we are frozen our bodies secrete endorphins that act to reduce pain, so that any physical or psychological injury is felt with less intensity.

Sometimes not fighting back is the best solution. You may dissuade a threat from causing you further harm, or you may escape it all together. Other times, it is unhelpful, especially when this happens outside of dangerous situations.

This feels awful. Is there a way to turn this response off?

It can be uncomfortable to experience the fight-flight-freeze reaction. Sometimes, it may feel that the reaction and the flow of adrenaline will never stop, or that you may never feel “normal” again. Remember, your body and emotions have their own gravity – what goes up must come down. In time, you will again come back to your own baseline and feel back to normal.

The fight-flight-freeze response is an absolutely crucial part of your body. In fact, in incredibly rare cases, some people are biologically unable to feel fear and to experience this fight or flight response. What we know from these cases, unfortunately, is that these individuals are likely at increased risk for injury and traumatic experiences. When your body cannot experience danger at the biological level and engage your sympathetic nervous system as expected, you cannot react quickly to keep yourself safe from potential threats. You need your alarm system. (For a fascinating listen on what it’s like to live without being able to experience fear, listen to the Invisibilia podcast episode “Fearless” starting at 9:37).

The Special Case of Trauma

While the fight-flight-freeze response is normal, adaptive, and necessary for our survival, there are times that our experiences can cause it to malfunction. Trauma is one of those special cases, and it can throw our natural fight-flight-freeze response off. This happens because when someone experiences a traumatic event, your brain gets flooded with many different neurochemicals which can overload the brain’s natural ability to respond to a potential threat.

The way the brain “learns” is by associating certain events and situations with how it will release (or stop releasing) neurochemicals. With trauma, the brain associates the trauma with over-activation and stimulation. And when people who have experienced a trauma are back in a situation that feels similar to the traumatic situation, they will again be flooded (and override the natural fight-flight-freeze response). So, if you grew up in an abusive household where there was a lot of yelling, it’s possible that any time someone yells at you, your trauma response will kick in, your brain with over-stimulate, and your fight-flight-freeze response kick into high gear whether you need it to or not.

Engaging in treatment for your trauma can help get this system back up and functioning correctly again. This works by helping people engage with their trauma memories in a different way, which allows for the brain to resume normal neurochemical release during stressful situations.

So, the next time that you experience an uncomfortable or potentially unsafe situation, and you get that familiar kick of adrenaline (or panicky kick of adrenaline, however you experience it), know that this is your body doing exactly what it is supposed to do, and that it will not last forever. And if you feel like your system gets activated even when it does not need to, you might consider exploring the several effective treatments for trauma.