What are the Polyvagal Theory and Vagus Nerve?
Feeling safe and being socially engaged are extremely important for overall health. Important hormones which are critical to our immune system are released, bodily functions operate better, learning improves, and more. If you do not feel secure, it is difficult to form social bonds and your body undergoes negative physiological responses that, over time, may result in chronic conditions such as, but not limited to: IBS, Fibromyalgia, and Depression.
The Autonomic Nervous System (ANS) is made up of the sympathetic, parasympathetic and enteric nervous systems. The ANS regulates the body’s internal environment to maintain its equilibrium, which is called homeostasis. Per the Polyvagal Theory, there are three autonomic states that are regulated by the ANS. We can be in any one of these states at a given time.
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Safe, Social Engagement - We feel calm and good. In this state, the heart rate slows, digestion is stimulated, facial muscles are activated and more demonstrative, and more eye contact occurs. Hearing is more attuned to frequencies of the human voice. Vocal prosody, which is the rhythm, stress and intonation of speech, is more expressive. Important hormones for the immune system are released. Critical thinking and learning improve. All of this allows for socialization, forming bonds, and improved overall health.
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Danger, fight or flight - We feel anxious. In this state, the heart rate increases, pain tolerance increases, facial expressions become more flat, and vocal prosody decreases. Ear muscles work to tune out the mid-range frequencies of the human voice in order to hear more high/low frequencies that are associated with dangerous sounds. Critical thinking and learning are compromised.
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Extreme life threatening danger - In this state, the nervous system shuts down and the body literally freezes and disassociates. This is important in understanding trauma and/or PTSD, and why victims may not fight back or run away; they can’t. The nervous system does not allow it, as it has shut down. This response is completely physiological and non-voluntary.
Our autonomic state is the lens through which we experience the world and it is determined by a subconscious process called Neuroception. Neuroception is our unconscious, instantaneous, automatic scanning of the world around us to assess safety. The Vagus Nerve, which is part of the ANS, links the brain stem to the gut and all of the body’s organs. Based on neuroception, the Vagus Nerve tells the body which autonomic state it is in and the body reacts accordingly. Two people can experience the same environment quite differently based on their autonomic state. You may even experience the same situation differently depending on which autonomic state you are in at given time. Based on evolution, the body has a tendency toward the danger states, which is unhealthy and can be harmful. Therefore, it is important that your Vagus Nerve is working optimally.
The Vagus Nerve has two branches, Ventral and Dorsal. The Ventral Vagus branch acts to calm the system and allows it to be in the safe social engagement state. Feeling calm and socially engaged is integral to being happy, healthy and forming bonds. The Dorsal Vagus branch is associated with the danger and extreme danger states. Healthy individuals can easily move between the safe social and danger states. Less healthy individuals, such as those with anxiety, trauma, and PTSD, have trouble moving between these two states and spend more time in the danger state. Thus, it is important for these individuals to strive toward having a strong Ventral Vegas branch to improve their health and happiness.
Vegas Nerve function is measurable, and it can be strengthened through specific manual techniques, self care, and other treatments. I have been trained in these techniques and welcome the opportunity to include them in your treatment plan as appropriate.