Why Your Nervous System Reacts the Way It Does (Understanding Trauma Responses)

Trauma survivors often deal with unexpected triggers and trauma responses. These can be frightening or frustrating, especially when the reason the reaction is happening is unclear. Although this article can’t tell you why your exact experience is happening, it can help you understand the defenses your nervous system uses. Understanding this can remove some of the confusion or fear.

What trauma responses are trying to do

The most important thing to understand about nervous system defensive responses is this: the most important job your nervous system has is to keep you alive. Its job is to keep you alive even if it means you are scared, unhappy, or numb.

We all come with a range of nervous system defenses. Two commonly known defenses are fight and flight. What becomes individualized is when those defenses are used and how those defenses present. Your defenses developed because they increased your safety or reduced harm to you.

Another important fact to understand is that these defensive responses are not chosen consciously in the moment. So if you froze instead of fighting or fleeing, that was not a conscious choice. It was a choice made by your nervous system.

Why trauma responses continue after the danger is gone

Keeping in mind that the nervous system’s number one priority is keeping you alive, it won’t surprise you that it values safety over accuracy. That is, your nervous system would rather react to 20 false alarms than fail to react to a single incident of true threat. This means you may find yourself experiencing a trauma response even though you are consciously aware of no danger. You may be truly safe, but if your nervous system detects a cue that it associates with danger to you, it will react with a trauma response. In these instances, being safe and feeling safe are not necessarily the same thing.

Your trauma responses continue after the danger is gone because the repetition over time has made them fairly automatic. Because these responses helped you survive in the past, the nervous system tends to continue using them until it learns they are no longer necessary. Often, this involves having to make efforts to teach your nervous system that they are no longer necessary.

Fight: when the nervous system tries to remove the threat

The fight response occurs when your nervous system decides that the best way to respond to a threat is to confront it directly. Fight is often thought of as a solely physical response, such as punching or kicking, but fight can show up in other ways, such as:

• anger
• irritability
• controlling behavior
• arguing
• pushing back

The fight defense is based on the idea that if you can confront the threat and overcome it, then you will be safe.

Flight: when the nervous system tries to escape the threat

On some occasions, your nervous system will determine that the threat you are facing is too strong to be overcome. If you try to fight it, you will likely not succeed and could even be harmed more as a result. Flight is based on the idea that if you can get away from the threat, then you will be safe.

As with fight, people often think of flight as a physical action, such as literally running away. But the flight defense can show up in other forms:

• avoidance
  • staying constantly busy
  • using substances
  • daydreaming

Freeze: when the nervous system becomes stuck

Sometimes you may find that you can neither fight nor flee; you are frozen and immobile. The logic behind this defense is that if you can stay still, you might not be noticed and targeted by the threat, allowing you to survive. The freeze response can be physical or it may show up as:

• difficulty acting
• indecision
• mental blankness
• feeling trapped

Fawn: when the nervous system tries to maintain safety through relationships

All mammals rely on others in their community for safety and protection, humans included. Humans depend on relationships for safety to an even greater extent. A human on their own in the wild has few resources. We don’t have claws, aren’t huge or immensely powerful, and so on. As a group, however, we become formidable. Relationships can be the difference between life and death, therefore, the nervous system will do what it can to protect those relationships. The defense called fawning is exactly that: it is focusing on keeping important relationships intact by keeping the other individuals happy. It can look like:

• people-pleasing
• excessive apologizing
• difficulty saying no
• focusing on others’ needs
• conflict avoidance

Shutdown: when the nervous system reduces activity

Shutdown is a defense that reduces demands upon the person mentally, emotionally, and physically. In this defense, the nervous system shifts into a state of reduced or even minimal functioning. Emotions that were overwhelming no longer seem as strong. Things may seem less important. The pressure accomplish tasks or handle situations drops. The nervous system enters shutdown when the demands upon it exceed its resources. In other words, the nervous system may choose shutdown when it becomes overwhelmed. Shutdown can look like:

• exhaustion
• numbness
• loss of motivation
• inability to care
• reduced functioning
• feeling disconnected from goals

The focus of shutdown is to conserve energy and reduce demands upon the body. It often does this through reduced activity and reduced engagement with the world.

Dissociation: when the nervous system creates distance from overwhelming experiences

Dissociation can also result from overwhelm. This defense can protect you by creating distance between you and the overwhelming experiences. The distance may come from emotional numbness or it might come from an inability to access distressing memories. It might come in the form of feeling separate from your body, as though you are merely observing it.

• detachment
• depersonalization
• derealization
• emotional disconnection
• memory disruptions

Dissociation protects from overwhelm differently than shutdown. Dissociation utilizes compartmentalization, separation (e.g. emotions for the distressing memory may be stored separately from the memory), and altered awareness to accomplish this.

A summary:

These responses are not mutually exclusive. People often experience several of them over the course of a day or even during the same situation.

Why different people develop different trauma responses

Although every person has these defensive responses, they are utilized differently by each person. Person A may grow up in an environment where people-pleasing and dissociation were most effective while Person B grew up in an environment where fighting and shutdown were most helpful. Person A will most often default to people-pleasing and dissociation, but that doesn’t mean they never use the other defenses. They just may not use them as often.

Why you may use more than one trauma response

While we have access to a handful of defensive responses, we often default to one or two that helped us the most growing up. However, we will use other defenses when our nervous system determines they will be helpful. The defensive responses used depend heavily upon past experiences and on the present situation. Here are two examples to help clarify this:

• A child may learn to use fawning with a critical parent by becoming helpful, agreeable, and attentive to the parent’s needs. However, that same child may use freeze when confronted by a physically intimidating peer because staying quiet and unnoticed feels safer than engaging. The nervous system is not committed to a single response. It uses whichever response seems most likely to reduce danger in a particular situation.
• Imagine that Jordan receives an angry email from their supervisor. First, they become hypervigilant and reread the message repeatedly, looking for signs of danger. Then they spend hours overworking and trying to perfect their response. Later, overwhelmed by stress, they find themselves staring at the screen unable to think clearly. In a single situation, Jordan has moved through flight, hypervigilance, and freeze responses.

Defensive responses are not fixed categories and people often move from one to another. This becomes even more apparent when you look at your system. Some parts use fight as their primary defense. Others shut down. But if the situation called for it, many times they could use a defense other than their primary strategy.

Trauma responses can also change over time. A response that worked well in one environment may become less useful in another, leading the nervous system to rely more heavily on a different defense.

Why understanding trauma responses matters

Understanding trauma responses can be important for survivors. When you understand the logic of a response, it becomes less frightening. You may feel less out of control. You can appreciate how it originally did help you, even if it’s less helpful in the present. All of this helps to reduce self-blame and shame. Instead of focusing on the response itself or wishing it didn’t happen, this understanding may make it possible to focus your attention on determining whether it is still needed. If you determine it is not, you will have more resources available to you to work on changing that trauma response than if you were fighting the response or attacking yourself for having it.

Where to go next

• Why Social Acceptance Feels Necessary for Survival
• Why Triggers Can Activate without Conscious Awareness
• Trauma Responses in Daily Life
• Understanding Trauma Survival Strategies

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