Meet Your Vagus Nerve: Parasympathetic Nervous System Anatomy

Everything in the body is connected. This becomes most apparent when you look at the anatomy of your nervous system—its communication expressway. Your body is performing numerous functions unconsciously at any given time. The nervous system tells your body what to do, especially in response to stimulation, at the unconscious level. 

The vagus nerve, part of the parasympathetic nervous system, soothes your entire nervous system when stimulated. Vagus nerve stimulation improves functions in the body involved in relaxation and digestion, providing compounding benefits. In this post, we'll look at these benefits and ways to stimulate your vagus nerve.

What Is the Parasympathetic Nervous System?

Nerves are fibers found throughout the body that act as cables, relaying messages to and from the brain. The parasympathetic nervous system is part of the autonomous nervous system, which deals with communications related to unconscious activities such as your heart's beating and your lungs' breathing. In contrast to the sympathetic nervous system, the parasympathetic nervous system is more active when the body's in "rest and digest" mode.

The Vagus Nerve: a Parasympathetic Controller

Like a circuit running from your brain through your torso, the vagus nerve picks up on stimuli and feeds the information to your brain. It's heavily involved in regulating the parasympathetic nervous system by inducing relaxation, lowering the heart rate and blood pressure, as well as stimulating digestion. The vagus nerve even helps the brain process the "gut feelings" we sense.

What Is Your Vagus Nerve?

The vagus nerve is the body's longest nerve. It's actually a pair, with the left and right vagus nerve on either side. Starting at the brainstem, the nerve travels alongside your respiratory system down to your abdomen. Its job is to relay information from these areas to the brain, such as sensory inputs from your throat and lungs.

The Gut-Brain Connection

You may have heard that your gut is your "second brain." Research published in Frontiers in Neuroscience in 2018 explains that microbes in the gut release brain chemicals like serotonin, dopamine, and acetylcholine. The vagus nerve picks up these messages, as it has "interoceptive awareness"—the ability to listen (chemically) to your gut and translate messages to your brain. Hence, the link between microbes and your mood.

Why You Should Stimulate Your Vagus Nerve

Any technique that promotes activity in the vagus nerve can potentially provide compounding health benefits by stimulating the entire parasympathetic nervous system. Here are the major benefits:

Fights Inflammation

When stimulated, the vagus nerve sends signals that balance the immune system's inflammatory response. If you have chronic inflammation, stimulating your vagus nerve can have an anti-inflammatory effect—and in turn, lower your risk for injury and disease.

Lowers Stress

The vagus nerve plays a huge role in your body's recovery from stress. Vagus nerve stimulation can improve your mood and reduce symptoms of anxiety. Stimulating your vagus nerve also lowers blood pressure and brings your pulse down. These effects, associated with parasympathetic nervous system activity, help promote feelings of calmness and relaxation.

Improves Digestion

By "waking up" the muscles throughout your digestive tract, stimulating the vagus nerve improves digestion. By promoting relaxation and shifting the body's focus to digestion, vagus nerve stimulation could potentially help you assimilate more nutrients from the food you eat.

Vagus Nerve Stimulation Techniques

There are simple at-home practices you can do for vagus nerve stimulation, plus the option to use a medical device. Here are some of the best ways:

1. Breathwork

With slower, deeper breaths, the diaphragm signals to the vagus nerve that it's time to relax. In turn, the vagus nerve tells your brain. Research on the effects of pranayama, qi gong, and other traditional breathing practices show vagus nerve stimulation is central to their mental and physical benefits.

2. Cold Exposure

Have you ever felt more relaxed after a splash of cold water to the face? It sounds counter-intuitive, but exposure to the cold stimulates the vagus nerve, which in turn tells your entire body to relax. Exposing yourself to cold with a cold shower is a great way to activate your vagus nerve. Over time, regular cold exposure is found to strengthen the nervous system and increase your resilience to stress.

3. Singing and Humming

Singing, chanting, and humming activate the vagus nerve by activating the muscles in your throat and producing a vibration. This natural stimulation technique sends feelings of relaxation from the throat area to the brain. Humming through your nose, chanting "om," or singing a song can slow your heart rate and breathing.

4. Take a Probiotic Supplement

The vagus nerve is continually picking up on the gut feelings in your digestive tract. Probiotics are friendly bacteria that stimulate the vagus nerve from the gut, sending visceral feelings of calm. In a 2011 study, researchers looked at the effect of probiotics on the vagus nerve in mice. They found that the vagus nerve was responsible for translating positive signals from probiotics to the brain, which reduced anxiety- and depression-related behaviors in the mice.

5. Use a Vagus Nerve Stimulator

A vagus nerve stimulator is an FDA-approved medical device designed to provide continual stimulation through a subtle vibration at the base of the neck. With the device on your skin for a couple of minutes a day, electrodes send micro-vibrations into your body felt by your vagus nerve. The effects have been shown to combat headaches and migraines.

Soothing the Vagus Nerve for Better Health

Some of the ways you can stimulate your vagus nerve are by singing, chanting, humming, breathwork, and taking a cold shower. You can also supplement with probiotics and try a vagus nerve stimulator to reap the benefits of vagus nerve stimulation.