Soundwork for Nervous System Regulation, Pt.2 – The Vagal Nerve

Recent interest in the vagal nerve (VN) has been driven by research breakthroughs, clinical studies, and technological advances. However, societal factors also play an increasing role in VN interest. 

Mental health has become a large arena of concern. With the rise in stress-related disorders (anxiety and depression), and a shift toward understanding the neurological bases of mental health, the vagal nerve and autonomic nervous system are increasingly considered. The Polyvagal Institute considers the VN to be “…a path to wellness.”

The Vagal Nerve 

The vagal nerve (VN)  – also known as the vagus nerve – has long fascinated researchers. Pre-200 CE, Greek and Chinese physicians had already identified this unique wandering nerve.  Based on the Latin word, vagary (to wander), the VN emerges from the medulla oblongata (brain stem) and meanders all the way through the torso, terminating in the colon. 

Along the way, the vagus innervates many organs, including the pharynx, larynx, esophagus, heart, lungs, stomach, liver, gallbladder, pancreas, small and large intestines, spleen, and kidneys.

Innervation is the term applied when a nerve connects to and provides nervous system input to an organ, muscle, or tissue. If we think of innervation as electrical wiring, the vagal nerve provides the signals to control or inform a part of the body. It also allows for two-way communication between the brain and the organ.

One of the leading researchers in VN is Dr. Stephen Porges, creator of a highly significant body of work, known as Polyvagal Theory. A professional institute supports the teaching and training Polyvagal Theory. Given that the VN is a large part of their therapeutic theories, I’m including their definition of the VN:

“The vagus nerve is a primary carrier of information describing the state of the body to the brain and transmitting information from the brain back to the body. It’s a feedback mechanism which is responsible for maintaining homeostasis for many of our vital organs and brain/body functions.  Research over the past few decades shows that the vagus plays a key role in managing our levels of stress as well as our body’s inflammation; in this age of stress- and inflammation-related disease, it is perhaps the most important nerve in the body for us to be paying attention to.”

Human brain nervous system anatomy, medical diagram with parasympathetic and sympathetic nerves, medically accurate. 

VN and Autonomic Function

The 10^th of 12 cranial nerves, the VN is also the longest nerve in the body: approximately 24 inches in most adults, consisting of right and left branches, each carrying thousands of sensory and motor fibers. 

The importance of the VN to the autonomic nervous system (ANS) centers around the VN being a key communication link for the parasympathetic nervous system (PNS). The VN helps the PNS regulate essential involuntary functions like heart rate, breathing, and digestion. Vagus contributes to calming the body by providing a rest and digest function after stress has triggered fight or flight responses from the sympathetic nervous system (SNS).

The VN is considered one of the most significant nerves in the human body. Because it is inextricably tied in with the PNS, stimulation of the VN has a direct PNS influence, thereby affecting autonomic equilibrium. Tonification methods for the VN includes sound (humming, singing), deep breathing, exercise, cold, and various emotional states.

Every body is different. Every vagal nerve is different. Adaptation is a key consideration for retuning the 21^st century human mechanism. The concept of sound and breathwork for nervous system regulation is an inquiry into autonomic equilibrium. 

The vagus nerve and autonomic equilibrium: Sound -> Breath -> Vagal tonification -> Parasympathetic NS stimulation -> Counteraction to sympathetic NS overdrive.

Vagal Nerve Stimulation

There are two vastly different VN stimulation techniques: Vagal Nerve Tonification and Vagal Nerve Stimulation. 

• VN Tonification (VNT) generally refers to increasing vagus tone through various mild holistic methods (breathing, humming, exercise, etc.). The goal of VNT is the enhancement of vagus nerve function. 

• Vagal Nerve Stimulation (VNS) refers to medical treatments involving electrical stimulation of the VN. The primary goal of VNS is to use electrical impulses to modulate the activity of the VN and its associated brain regions, ultimately aiming to improve a variety of medical conditions. VNS can help reduce seizures in epilepsy, alleviate treatment-resistant depression, and potentially aid in stroke recovery. 

There are potential risks associated with vagal nerve stimulation, especially if done incorrectly or if certain medical conditions exist. Always work with a medical practitioner when using VNS.

Vagal Nerve Research

Recent research concentrates upon:

• 1985: First vagal nerve stimulator implanted for epilepsy

• 1990s: Polyvagal Theory developed by Stephen Porges

• 2000s: Discovery of vagal influence on immune system

• 2010s: Increased research into non-invasive vagal stimulation

• Recent years: Growing interest in vagal tone's role in mental health. 

There is a great deal of attention on the Vagal Nerve within the sound community. I first came across the vagabond nerve in 1998, when researching the work of Alfred Tomatis. At that time, I mistakenly considered the VN as a justification of the power of sound. I assumed that because the VN had a relationship with the auditory mechanism, and then continued on to innervating all torso-based organs, that it meant that all sound vibration coming into the ear was therefore impacting all organs. This is not necessarily true.

VN involvement with the auditory system is actually quite minimal, primarily providing somatic sensations (touch, pain, temperature) to a small area of the external ear. It is the VN that is mostly impacting the ear and not auditory vibrations affecting the VN. I had it all wrong!

Where sound and the VN significantly intersect is with sound vibrations from the larynx and pharynx (throat area) essentially jumping onto the vagus train as it moves into the thorax and abdomen (heart, lungs, gut, etc.) In other words, it is by our self-made sound – not external sounds picked up by our auditory system – that we have a VN impact. By using our voices (singing, toning and with humming being the most powerful) we are tonifying the VN which directly impacts the parasympathetic nervous system, helping to bring equilibrium to the sympathetic NS.

Bottomline: If you want to have an organic, yet powerful impact on calming the NS, it can be as simple as humming (nasal inhalation/exhalation) for 5-10 minutes once or twice a day. I find that it really resets my sleepy brain if I do this as part of my morning practices and helps me sleep if done close to bedtime. Listen to your body and if you have a medical condition of any kind, consult a medical practitioner before doing any VN exercises. While breath/sound/VN exercises are simple and subtle, they can have a larger impact. Please note: I am a sound researcher and not a medical professional.

Further information: https://www.polyvagalinstitute.org

An upcoming blog will continue Soundwork for Nervous System Regulation. Pt.3 will look at why sound is important with Breath Ratios, specifically about 1:2 – How breathing with a double length exhale can make a big difference in the therapeutic utilization of breathing, and how sound helps make a longer exhale possible.