People seeking treatment often believe there must be something wrong with them, that their brain is “broken” — this simply is not true. In fact, your brain is working hard to protect you. The brain is constantly looking for ways to feel safe. It reacts when it does not feel that you are. This article will discuss parts of the autonomic nervous system. This is the part that is automatic. It is not controlled by conscious effort, rather it senses a need and responds accordingly.
What you will find in this article:
- Fight or Flight Response
- Freeze Response
- Impact on Social Connection
- Feeling Safe
Fight or Flight Response
Have you ever felt like you were on edge or like you want to run away though you are just sitting in a room with your family? This is the hyperarousal state of fight/ flight.
Some Identifiers of Fight/Flight Response:
- Hypervigilance
- On edge / jumpy
- Chest tightness
- Fidgeting / bouncing legs
- Excessive worry
- Racing thoughts
In this state, the body is sensing danger. The body has an excessive amount of energy in this state. Imagine living in prehistoric times when saber-toothed tigers roamed the planet. If you were being hunted by a saber-toothed tiger, it would behoove you to have an excessive amount of energy pulsing through your body so that you can either run away from or attack back with greater power than you otherwise would normally have while relaxing by the fire.
The challenge is that your body cannot distinguish between the danger of being hunted by a giant cat, and the perceived danger that is felt after continually being exposed to traumatic events. The results are the same. You cannot feel safe and you cannot rest.
Freeze Response
The freeze response goes one step further than fight or flight. The body is no longer concerned with danger, it fears death. It senses that there is a life threat.
Some Identifiers of Freeze Response:
- Low energy/ fatigue
- Agitation/ irritability
- Depression
- Numbness/ dissociation
In this state there is a depletion of energy. This has two important functions:
1) It stops the flow of energy so as to build it up. Similar to kinking a hose- it stops the flow of water, and then when it is released it bursts before returning to a normal flow. Going back to the saber-toothed tiger analogy, if you were being attacked by this large animal, it would be highly beneficial if when you regained consciousness, you had an explosion of energy to escape.
2) The freeze state eliminates physical pain. Again, with the prehistoric cat, if being attacked it would be useful to not feel that pain. In our day-to-day lives, however, we are not being attacked by lions, tigers, and bears.
Emotions are called feelings because we physically feel them. Think about where you feel stress in your body. Your shoulders? How about anxiety? In your chest? In a frozen state, not only is the person unaware of their physical pain, they are numb to their emotional experiences as well. We cannot selectively numb our feelings, so when numbed to painful emotions, we are numbed to pleasurable ones as well.
As first responder jobs often result in living in a fight/flight (excess energy) state, your body recognizes that it will eventually run out of energy. Becoming numb, dissociating, and isolating from others or turning to alcohol, benzodiazepines, and other depressants, your body intuitively knows that it cannot stay in this heightened state or it risks dying. This is not to condone substance misuse, rather to gain understanding of what function it serves. Healthy alternatives will be discussed in the section on safety.
Impacts on Social Connection
Fight, flight, and freeze are classified as sympathetic nervous systems responses. When in a sympathetic response, not only is someone experiencing the symptoms described above, their ability to connect with others is impeded. While the shame from trauma and other mental health struggles often tell us a different message, humans are the most social creatures in the animal kingdom and we cannot live without one another. Social disconnection is detrimental to our physical, psychological, and spiritual wellbeing.
Social Impacts of the Sympathetic Response
- Lose the ability to hear higher pitched sounds (ie. the sound of human voices)
- Gain a greater ability to hear low-pitched sounds (ie. footsteps behind you, or rustling in the bushes)
- This is why when sitting at a restaurant it is challenging to hear the person sitting across the table, but the sound of the crowd is deafening
- Decreased ability to emote feelings/ facial expressions
- Decreased ability to empathize with others
Feeling Safe
The goal is safety. This is the parasympathetic nervous system response. In this state, true rest and recovery is possible. One of the primary purposes of mental health treatment is to help clients increase feelings of safety and move into their parasympathetic nervous system. Mental healthcare works to help the body learn this state as its new “normal.” This allows for when the sympathetic nervous system goes into action the body can quickly return to the parasympathetic response when the danger has been averted.
Some Ways to Stimulate the Parasympathetic Nervous System
- Slow deep breathing (ie. box breathing and Breathworks)
- Stretching tight muscles (ie. yoga)
- Physical activity (ie. going to the gym)
- Massage
- Cold compress to the side of the face and neck
- Eating a sweat treat (not in excess)
If you, or someone you love could identify with the cycle of fight/flight to freeze and back to fight/flight without feeling the true rest and recovery and parasympathetic responses, know that you are not alone, and you are not broken. The body is doing the best it can to keep you alive and out of danger. It may just need some help learning how to feel safe.
References:
- Cleveland Clinic Medical. (2024, December 19). Parasympathetic Nervous System (PSNS): What it is & function. Cleveland Clinic. https://my.clevelandclinic.org/health/body/23266-parasympathetic-nervous-system-psns
- Porges, S. W. (2001). The polyvagal theory: Phylogenetic substrates of a social nervous system. International Journal of Psychophysiology, 42(2), 123–146. https://doi.org/10.1016/s0167-8760(01)00162-3
- Weissman, D. G., & Mendes, W. B. (2021). Correlation of sympathetic and parasympathetic nervous system activity during rest and acute stress tasks. International journal of psychophysiology : official journal of the International Organization of Psychophysiology, 162, 60–68. https://doi.org/10.1016/j.ijpsycho.2021.01.015
Clinically Reviewed & Written By:

Dr. Rose Maynard, PsyD
Rose Maynard, a Licensed Marriage and Family Therapist, holds a Doctorate and Master's degrees from Alliant International University and a BA in Psychology from Vanguard University. She is trained in trauma-specific modalities, including EMDR, ART, and TF-CBT.