Polyvagal Theory: What’s Your Nervous System Got to Do With It?

Have you ever been flooded by a sense of dread—almost frozen to the spot? Maybe you suddenly feel the urge to run or to fight an attacker? These responses are a result of your nervous system.

Your nervous system has many ways of keeping you safe and alert and assists in the split-second decision-making in your daily life. When healthy and functioning well, this system operates effectively and equips you to live well.

But what happens when your nervous system becomes over or under-reactive? Signaling danger at daily noises, or ignoring the fire alarm of real danger?

What is Polyvagal Theory?

For decades, psychologists have studied the way our nervous system impacts our thoughts, behaviors, and regulation. One important component of this research is the polyvagal theory, first developed by Stephen Porges. It is centered on the importance of the vagal nerve, which is the longest cranial nerve, and “it oversees a vast range of vital functions communicating sensory input from outside triggers to the rest of the body” (Davis, 2020).

The vagal nerve is essential in understanding how a brain interprets its surroundings and then responds. This is especially important when working with individuals who have experienced trauma because those events impact the way the nervous system interprets situations and what messages it sends to the body on how to respond.

Davis further explains that the “polyvagal theory emphasizes the evolutionary development of two systems: the parasympathetic nervous system which is ultimately connected to the vagal nerve and the sympathetic nervous system.

“Each has its own function, and cause the body to react differently before, during, and after a traumatic or stressful event. If these two systems become damaged from excessive and recurrent trauma, a break down occurs and mental illnesses such as CPTSD and anxiety disorders may result” (Davis, 2020).

Basically, traumatic experiences can greatly impact the way the parasympathetic nervous system interprets the environment, and often needs to relearn healthy ways to interact and interpret daily life after a traumatic event.

Polyvagal Theory and the Anatomy of the Nervous System

Since the vagal nerve is central in the automatic nervous system, it is important to understand how damage to different parts of the system impact an individual.

Parasympathetic system

“The parasympathetic, [or] ventral vagal, refers to the front part of the vagus nerve. This nerve starts from the

brainstem and meets up with the cranial nerves of the face, ear, travels down to the throat and larynx, and makes its way to the heart…In this state, heart rate is ready to respond to nuance…Ventral vagal is our safe and social mode. It is the state we are in when feeling OK in our own skin, regulated, safe. In this state, we can focus, talk easily, think clearly” (Karaca, 2022).

Sympathetic system

Karaca further explains that “the sympathetic branch…runs down the lumbar part of the spinal cord. This mode prepares the body for mobilization, raising the heart rate, taking blood from the stomach to the muscles, focusing the eyes and other senses, filtering out the sound of human voices and listening for sounds of danger. Sympathetic has adaptive and survival purposes.

Adaptive is playing, running, hunting, and moving, e.g. competitive sports and survival, fight/flight. When we are in sympathetic, we might try to avoid situations, feel irritable or anxious, social situations feel stressful, we may overthink, catastrophize and organization is difficult” (Karaca, 2022).

Parasympathetic – Dorsal Vagal Nerve

“The dorsal vagal is the rear part of the vagal nerve. The dorsal vagal goes from the brainstem to the gut…Dorsal vagal has adaptive and survival purposes. Adaptive purposes include rest and digestion. In survival mode, dorsal vagal is employed when a situation cannot be fought or escaped and results in shutdown.

“…[this] is the state where we find it difficult to move…it may feel difficult to get out of bed or out of the chair, thoughts feel slow and foggy and motivation is really low. In this state, any social engagement can feel overwhelming” (Karaca, 2022).

It is readily apparent that polyvagal theory is essential in understanding how and why a brain is responding to events, environments, and people in certain ways. Furthermore, learning to be aware of and regulate these systems is imperative for a trauma survivor to heal.

How This Theory Impacts Trauma Therapy

There are many ways in which to incorporate the polyvagal theory into trauma therapy. For instance, the clinician can equip the client with tools to understand and regulate their sympathetic nervous system that may be over-functioning or “on” in inappropriate scenarios due to trauma impacting the interpretations, while also working to help the parasympathetic system develop its capacity to be “on” for the client (Davies, 2021).

This process can also be described as learning to know your “window of tolerance” which is when your nervous system begins to move out of parasympathetic mode to sympathetic mode, and thus out of your window.

Vagal Tone and Polyvagal Theory and Therapy

Vagal tone is the strength of the parasympathetic nervous system to be “on.” It can be developed and grow in its capacity.

Breathing Exercises

Since the vagal nerve is an integral part of the nervous system, which is responsible for our automatic bodily functions like breathing and our heart rate, polyvagal therapy can incorporate conscious breathing exercises.

Examples include box breathing (inhaling for 4-5 seconds, holding for 4-5, and repeating the sequence to make a “box”, and 5,6,7 breathing (inhale for 5 seconds, hold for 6 seconds, release for 7 seconds). Both of these exercises signal calm to the parasympathetic nervous system.

Dive-reflex stimulation

The dive reflex is the body’s natural response when the head goes underwater, and the nervous system sends signals to conserve oxygen. This stimulation can be done in many ways such as splashing your face with cold water, taking a cold shower, or holding your breath intentionally under water.

Comforting thoughts/people

Davies further articulates that visualization exercises can also stimulate the parasympathetic calming response when you think about comforting people, memories, or places that bring a sense of safety, warmth, and comfort (Davies, 2021).

The common factor in these exercises as a part of polyvagal theory integration into therapy is that the individual is consciously stimulating the parasympathetic nervous system through controlled exercises involving automatic functions of the vagus nerve.

Furthermore, for trauma survivors, these exercises can be practiced outside of polyvagal therapy in real-life situations as they learn to pay attention to their window of tolerance and to understand their unique nervous system cues of flight, fight, and freeze as they interact with their world.

In conclusion, Stephen Porges’ research of the vagus nerve resulting in the polyvagal theory is a foundational aspect of therapeutic intervention for survivors of trauma. The polyvagal theory is centered on the way the vagus nerve controls automatic functions such as breathing and heart rate, as well as interpretations of safety and threat. It thus signals the system to calm (parasympathetic) or take protective reactions (fight, flight, freeze).

These driving forces of interpretation and behavior are central to how every human interprets and interacts with their environment. Understanding an individual’s vagal tone and incorporating exercises to increase its strength can be effective in equipping them to heal their nervous system’s reactions and inclinations rooted in traumatic events. Polyvagal theory and polyvagal therapy are central to therapeutic interventions.

To learn more about how polyvagal theory can be applied to therapeutic treatments to help you, contact a qualified Christian counselor today.