How to Strengthen the Vagus Nerve to Improve Pain: Part One

Recent developments in pain science involve the vagus nerve and the autonomic nervous system, the part of the nervous system that regulates automatic functions like breathing and heart rate. The autonomic nervous system consists of the sympathetic nervous system known as "fight or flight" which is a response to a THREAT and the parasympathetic nervous system known as "rest and digest" in response to SAFETY. There is another component of the parasympathetic nervous system known as "freeze or fawn" that is triggered when your nervous system responds to a significant threat as described by the Polyvagal Theory by Stephen Porges.

The vagus nerves are paired cranial nerves, originating in the primitive part of the brain known as the brain stem. Altough there are two nerves, one on each side of the body, the vagus nerve is often referred to in the singular sense. Each vagus nerve divides into two segments, the ventral and dorsal branches. The ventral is in front of (anterior) and the dorsal is behind (posterior). Both parts of the parasympathetic system, the ventral vagal state creates a sense of safety and calm while the dorsal vagal state creates immobilization and shut down. The sympathetic nervous system is protective by mobilizing you to action in the presence of a threat so you can escape harm. It is vital to understand the NORMAL response to cues in your environment to keep you in a state of safety. It is also important to know that the response is physiological and not psychological; in other words, what happens is a normal response to the environment you are in so your brain can do its job of keeping you alive.

Let's say you have a life threat that spikes your nervous system rapidly into the primitive part of the vagus nerve known as dorsal vagal or red zone, similar to what mammals do to "play dead". The graphic above demonstrates this. This is a normal and expected reaction and your body should return back to the green zone of safety once the threat is over. What is not normal is that the nervous system can get stuck or it can get triggered easily when there isn't a life threat. This is the basis of PTSD (post traumatic stress disorder) and many psychological disorders. The good news is the nervous system can be recalibrated due to a concept known as neuroplasticity.

Another example is an injury or trauma to the abdomen or pelvis such as during a fall or contact sports. The brain automatically protects the organs by tightening the connective tissue known as fascia which signals to the brain something has happened and it should protect the area further. This is part of muscle memory and why someone might have pelvic pain, poor digestion, menstrual cramping and/or muscle dysfunction. If you further guard and protect the abdominal area due to pain, it creates a feedback loop, keeping muscles clenched and organs lacking normal motility (think constipation). Receiving safe touch through hands-on manipulation of deep fascia through a technique we use called visceral mobilization gives positive feedback to the brain, bringing to consciousness a sense of safety and bringing the nervous system back into balance. The vagus nerve is 80% sensory, receiving most of the information going to it from the senses such as touch. You can go from one state to another by overriding the subconscious and becoming more mindful, which is known as nerve mapping. Additionally, stimulating nerves in the face and head (above the diaphragm) is very powerful and can change the brain quickly due to the myelinated sheath that is part of the ventral vagal system. You can read more on vagus nerve exercises in Part 2 of this blog here.

To further understand the physiological response, it is important to know that 90% of the brain is subconscious and only 10% is conscious. Much of what you feel in your body does not come to your consciousness and why it is essential to be mindful of mapping your nervous system to bring the other 90% of your brain into consciousness. This is part of what we call the "gut feeling" from the enteric nervous system, or "gut brain". It is also why what you eat matters since there are more neurons going to the brain than from the brain. Sadly, the Standard American Diet (SAD) is nutritionally poor and full of pesticides and other artificial (man-made/ factory-made) ingredients that the body doesn't recognize. If the gut is inflamed, the nerve signals going to the brain are altered and can cause inflammation in the brain that we sense as irritability, anxiety, depression, etc. A healthy mind needs a healthy gut!

The Vagal Brake

The vagus nerve acts as a brake to down regulate the "fight or flight" response. In individuals who have experienced trauma or chronic pain, the vagus nerve may not be functioning properly due to low vagal tone. The good news is you can improve vagal tone with regular practice. According to Stephen Porges, "when we are social and are engaged, we are reducing metabolic demands to facilitate health, growth and restoration." Having the vagus nerve working optimally is critical to your health and potential for healing. One way to reset your nervous system involves using mindfulness to override the instinctive reflex of automatic breathing. By recognizing when you are holding your breath or breathing shallowly, you can encourage yourself to take deep, diaphragmatic breaths. This action stimulates the vagus nerve, calming your nervous system and reducing respiration and heart rate.

Triggers and Glimmers

Deb Dana in her book, The Polyvagal Theory in Therapy, explains triggers and glimmers. A trigger is anything that the brain perceives as unsafe. A glimmer is the opposite, creating an optimal state in the nervous system where the vagus nerve is stimulated and "social engagement" can occur. Some examples of glimmers are: petting a dog, going to a concert, relaxing at the beach, spending time in nature, exercising under optimal conditions (in the absence of pain or excessive temperature), getting a massage, getting hands-on therapy (what we do at Healthy Core), and spending time with others who you are in a healthy relationship with. Here's an important concept that we have learned; you need to intentionally seek glimmers, especially if you know you might be triggered in certain environments or with certain individuals and to do this BEFORE the triggering event. Take for example, firefighters like my husband. There are multiple triggers on the job, including the tones that ring when there is an emergency call. Before he starts his 7 am shift, we go through some of the cranial nerve resets mentioned below while ensuring he has a good night's sleep and proper nutrition. Cortisol levels are highest in the morning and can be a trigger in and of itself. I know he will have several triggers in his 24-hour shift so we intentionally include some "glimmers" before his shift. We intuitively have known this and did some of this throughout his 30-year career without understanding the science or reason behind it. Another example is intimacy. If you are stressed and not in ventral vagal, you will have poor libido or will not be able to become aroused. By adding some glimmers before intimacy, you can quickly regulate the nervous system and become present and in the moment. Our advice for someone who has a history of pain with sex is to breathe deeply from the abdomen, pull on the ears, play relaxing music and anything that promotes an optimal nervous system. You can read our blog on healthy intimacy here.

Vagus Nerve Resets

Changing your body's physiological response to your environment is possible through the stimulation of the vagus nerve and the cranial nerves that share space in the brainstem or are in close circuitry to the the vagus nerve. We will cover more specifics in Part 2 of this blog to learn how to simulate the other nerves of social engagement, namely the trigeminal nerve (cranial nerve V), facial nerve (cranial nerve VII), glossophyaryngeal nerve (cranial nerve IX) and spinal accessory nerve (cranial nerve XI). It is easier than you might think and highly effective!

My experience with chronic pain for myself and for my patients has evolved exponentially since learning about and incorporating the polyvagal theory. I do not view pain the same and I now make more time to include intentional glimmers. Understanding how the body responds physiologically to an internal or external threat and knowing you can change ow the body responds is empowering in the healing journey. My hope is you will embrace this information and be able to incorporate it to prevent and reduce pain. If you need help getting started, call our office to schedule a physical therapy evaluation with one of our experts. Healthy Core therapists are trained to treat and teach you about pain science and healing from chronic pain. You can achieve a pain-free lifestyle to be the best version of yourself!

Written by Janine Laughlin - September 2022

References:

Reference Materials and Class Notes from Vagus Nerve Mojo Workshop by Perry Nickelston. January 2022.

Porges, Stephen. The Pocket Guide to the Polyvagal Theory. W. W. Norton & Co. 2017.

Dana, Deb. The Polyvagal Theory in Therapy. W. W. Norton & Co. 2018.