The Vagus Nerve
I have been thinking about what I wanted to write about in this blog entry. It can be problematic at times to come up with a relevant topic that can be insightful, educational, and easy to apply to everyday life. I kept coming back to the vagus nerve because of its importance to the human body. This nerve has several functions and responsibilities so it is hard to explain such complexity in a single entry. Therefore, I am going to attempt to give a simple and concise article on the vagus nerve.
The vagus nerve is designated cranial nerve number ten. There are twelve cranial nerves in total. Cranial nerves originate in the brain and brain stem with the focus of supplying the brain-body connection within the brain and mostly the head and neck. For example, the optic nerve transmits information from the eyes to the optic center of the occipital brain (back of the brain). Like many things in life, there always is an exception to the rule. The vagus nerve is the exception. This nerve leaves the brainstem and travels to several different organs of the body well below the typical head and neck area.
Like I said before, the vagus has many responsibilities. However, we are going to concentrate on the primary functions. The vagus utilizes 75% of its function to send information to the brain from the organs it controls.1 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. To explore how this system works, let us look at another example. If we were to place our hand on a hot stove, a pain signal is sent from the hand to the spinal cord and then to the brain. The brain says “Ouch, that’s hot, body move your hand”. The brain sends a signal back for an autonomic response to remove our hand and all is well. Now, the problem arises if those pain nerves in the beginning are ineffective, not working, or the signal is interrupted. The brain will act like nothing is wrong and we burn ourselves. Now the question you should be asking, “What organs does the vagus supply?”.
The vagus is included in the involuntary autonomic nervous system. This is the part of the nervous system where you do not actively think about doing its function. I will explain more on this later. 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). The focus needs to be on the heart and gastrointestinal tract.
The heart has a normal heart beat, right around 72 beats per minute. How do we maintain that specific heart rate? That is the responsibility of the vagus nerve. It automatically keeps the communication between the brain and heart to maintain that heart rate. Along with heart rate, the vagus plays a vital role in blood pressure. The blood pressure is handled just like the heart rate. Both are how the vagus nerve functions. Logic will dictate, the organs will not respond properly if the right signal is not sent.
As mentioned earlier, the vagus plays an important role with the gastrointestinal tract. The function of the vagus nerve is to stimulate smooth muscle contraction and glandular secretions in these organs. For example, in the stomach, the vagus nerve increases the rate of gastric emptying, and stimulates acid production.2
There are numerous people in our society that experience heart rate, blood pressure, and gastrointestinal problems. The vagus nerve could be answer. 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 location. The green bone is called C1 or atlas.
Understand that the diagram is for demonstrative purposes. The nerve does not sit on the bone itself. It is in a protective sheath. However, it shows that if there is a measurable displacement of the atlas or a structural shift in the upper spine it can lead to signal interference in the vagus nerve.
Assuming a person has low vagal activity (decrease activity of the vagus nerve), what can be done? There are some medical procedures that are currently being trialed. It involves implanting a electric stimulator on the nerve. This will apply constant signaling to the nerve in the attempt to stimulate and correct the low vagal activity.
A structural chiropractor, like myself, can look for, measure, and correct the measurable atlas displacement or structural shifts in the spine. This is obviously less invasive compared to the surgery. The corrections are precise and simple. After an initial care plan, we re-evaluate the patient to see if there is any improvement. Only a structural chiropractor can correct these shifts and displacements.
The possibility that structural corrective chiropractic care can help with blood pressure and intestinal issues is high. In fact, there are many case studies in peer reviewed journals showing the benefits of chiropractic related to these issues. We need to constantly look for alternatives to modern medicine and you need to ask yourself what the best option is for you. Structural correction is not for everyone plain and simple. But before undergoing any type of procedure, whether modern medicine or alternative paths, you need to evaluate all your options.
I hope this gives you some insight on the importance and role of the vagus nerve. Additionally, how structural correction can possibly help. If you have any questions, you can contact us via email.
1. “Basic and Clinical Anatomy of the Spine, Spinal Cord, and ANS. 2nd edition” G. Cramer, S. Darby. 2005