What happens in the vagus nerve, doesn’t stay in the vagus nerve…

::ba da bum::

If you’re like most people, you probably are unaware of the vagus nerve, better yet, you may have never heard of the vagus nerve, so we are going to get into it today. 

What is the Vagus Nerve?

The vagus nerve is the tenth cranial nerve.  Cranial nerves? Cranial nerves generally begin in the brain and brain stem and relay information between the brain and body; mostly the head and neck. However, the vagus nerve might just be the most interesting of all the nerves in your body...if I had to pick just one that is. 

Reason being is that the vagus nerve is the longest cranial nerve and so named because it “wanders” like a vagabond, sending out fibers from your brainstem to all the organs of your body.

The vagus nerve’s primary role is to captain your inner nerve center – the parasympathetic nervous system (I've talked about this on my understanding you "aOS" blog.) As a quick refresher, the parasympathetic nervous system is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and enteric nervous system.  The autonomic nervous system is responsible for regulating the body’s involuntary functions aka your "aOS" - automatic operating system. 

The parasympathetic nervous system operates as a complement to the sympathetic nervous system (stress reaction). Here a quick recap of which division is doing what in your body:

SYMPATHETIC

• "Fight or Flight"

• Speeds up your heart rate to "fight" or "run like hell"

• Slows down digestion

• Immune system suppression...this is a BIG one

PARASYMPATHETIC

• "Rest and Digest"

• Slows down heart rate

• Turns up digestion/motility

• Supports immune system function

ENTERIC

• Regulates the movement of water and electrolytes between the gut lumen and tissue fluid compartments. (Not diving into this today.)

In order for our bodies to be healthy, we need both of the systems to be working cooperatively. Our sympathetic nerve system helps us to flee from danger and perform ridiculous feats of athleticism when properly activated. On the other hand, the parasympathetic nervous system helps us to prepare for sleep and improve digestion and absorb vital nutrients.

Achieving a balance between these two subsystems of the nerve system is what we should be striving for.  Yet, it is very common to find ourselves being “stressed out” creating a dominance in our sympathetic nerve system.  This dominance is what can contribute to why many people suffer from high blood pressure, irritable bowel syndrome, diabetes, anxiety and depression, and other chronic inflammatory illnesses.

Although we cannot always control the environment around us that contributes to our elevated stress levels, there are things we can do on a daily basis to activate our vagus nerve and stimulate our parasympathetic nervous system.

Sorry, I got a little side tracked…back to talking about the importance of the vagus nerve. So, the vagus nerve has many responsibilities…but we are going to only address the primary functions.

The vagus nerve utilizes 75% of its function to send information to the brain from the organs that it controls.

Read that again.  THIS IS VERY IMPORTANT!

If the brain cannot interpret the information coming in, the brain will not know how to fix any problems going on.

‍So what organs does the vagus nerve supply? Check this out:

As we discussed earlier, the vagus nerve is included in that autonomic (involuntary) nervous system. Thus, the vagus is primarily responsible for voluntary muscles in the larynx and esophagus, supplying autonomic fibers to the heart, and contributing to the stomach and intestines (gastrointestinal tract).  For our intents and purposes, we will focus on the heart and gastrointestinal tract.

The vagus nerve is intimately involved with your heart.

The heart has a normal heart beat, right around 72 beats per minutes.

‍How do we maintain that specific heart rate?

‍Yup…the vagus nerve.

The way doctors determine the “tone” or “strength” of your vagus nerve (and your cardiac health) is by measuring the time between your individual heart beats, and then plotting this on a chart over time (ie. heart rate variability – HRV) Guess what I measure here during a new patient examination...yup your HRV or the capacity of ADAPTABILITY you presently have between your sympathetics and parasympathetics. Along with heart rate, the vagus nerve plays a vital role in blood pressure.  The blood pressure regulated just like heart rate.

The vagus nerve translates between your gut and your brain.

I hope when you hear "gut" you make that synonymous with your IMMUNE SYSTEM because, that's where the MAJORITY of your immune system lives! So your microbiome and health of your gut aka has a direct affect on your BRAIN because the vagus is communicating from the gut to your CNS (and vice versa.) They are doing studies to see whether there is a link between an unhealthy microbiome and incidence of MS, IBS etc. (interesting stuff.)

Aside from what I just mentioned, your gut utilizes the vagus nerve like a “walkie-talkie” to tell your brain how you’re feeling via electric impulses called “action potentials”. Needless to say, don’t second guess your gut instincts…they are very real!

Let’s try and bring it back full circle…

There are numerous people in our society that suffer from a chronic disease associated with sympathetic dominance (high blood pressure, IBS, etc..).

‍The vagus nerve could be the missing link.

‍When the nerve is inhibited and not working properly, the signals get challenged.  The figure below shows the location of the nerve (nervus vagus) at the upper cervical spine – the green bone is C1 or the atlas.

The visual is to demonstrate how if there is a measurable displacement of the atlas or a structural shift in the upper cervical spine, it could lead to signal interference in the vagus nerve. Assuming that a person has low vagal tone (a measurable decrease in the activity of the vagus nerve), what can be done?

There are some somewhat invasive medical procedures that are currently being trailed involving implanting an electric stimulator on the nerve. Additionally, there are "ear clip devices" that stimulate the vagus nerve as well (no surgery required.)  These approaches more or less apply various intensities and frequencies of vagus stimulation to the nerve to correct the low vagal activity.

Better yet, a Structural chiropractor, like myself, can look for, measure and correct the measurable atlas displacement or structural shifts in the spine. The possibilities that Structural chiropractic care can assist with regulating blood pressure and digestive issues is high. In fact, there are many case studies suggesting the benefits of chiropractic care in relation to these issues. Additionally, in all my years of practice, most patients who are under regular care see an improvement in their HRV and sympathetic/parasymathetic balance, again by positively impacting the Vagus nerve. 

Heart rate variability (HRV) is a widely accepted as an objective measure of overall HEALTH.

Regular CHIROPRACTIC care can increase HRV and facilitate a more adaptive nervous system.

It's a simple as that.