There are twelve cranial nerves in the body. They come in pairs and help to link the brain with other areas of the body, such as the head, neck, and torso. Some send sensory information, including details about smells, sights, and tastes. These nerves are known as having sensory functions. Other cranial nerves control the movement of various muscles and the function of certain glands. These are known as motor functions. While some cranial nerves have either sensory or motor functions, others have both. The Vagus nerve is such a nerve. It connects the brain to many important organs throughout the body, including the gut (intestines, stomach), heart, and lungs. It also plays a key part in the parasympathetic ‘rest and digest’ nervous system. This takes us to the topic of stress and its impact on the brain and body.
During periods of chronic stress, the body stays in high gear, with stress hormones like adrenalin and cortisol coursing throughout our body. These hormones play havoc with our entire body, create wear and tear on our brain, and over time, can induce a multitude of health problems like chronic pain, anxiety, mood swings, and gut inflammation. The Vagus nerve system comes to the rescue in times like these. It acts to counterbalance the fight-or-flight system and initiates a relaxation response in our body. It is one of the cranial nerves that connect the brain to the body. The Vagus nerve is a major part of how our bodies and brains function; without it, our bodies would not be able to do basic tasks, and by stimulating it we can receive powerful health benefits.
Vagus nerve anatomy and function
The Sensory functions of the Vagus nerve are divided into two components
· Somatic components: These are sensations felt on the skin or in the muscles
· Visceral components: These are sensations felt in the organs of the body
Sensory functions of the Vagus nerve include:
· Providing somatic sensation information for the skin behind the ear, the external part of the ear canal, and certain parts of the throat
· Supplying visceral sensation information for the larynx, esophagus, lungs, trachea, heart, and most of the digestive tract.
· Playing a small role in the sensation of taste near the root of the tongue
Motor functions of the Vagus nerve include:
· Stimulating muscles in the pharynx, larynx, and the soft palate, which is the fleshy area near the back of the roof of the mouth
· Stimulating muscles in the heart, which helps to lower the resting heart rate
· Stimulating involuntary contractions in the digestive tract, including the esophagus, stomach, and most of the intestines, which allow food to move through the tract
Vagus Nerve Stimulation
· Cold Exposure
· Acute cold exposure has been shown to activate the Vagus nerve and activate cholinergic (capable of producing, altering, or releasing acetylcholine)
neurons through Vagus nerve pathways
· Researchers found that exposing yourself to cold on a regular basis can lower your sympathetic ‘fight-or-flight’ response and increase parasympathetic activity through the Vagus nerve
· You can ease yourself into this by simply sticking your face in ice-cold water
· Try finishing your next shower with at least 30 seconds of cold water and see how you feel. Then work your way up to longer periods of time
· Deep and Slow Breathing
· It has been shown to reduce anxiety and increase the parasympathetic system by activating the Vagus nerve
· Most people take about 10-14 breaths each minute. Taking about 6 breaths over the course of a minute is a great way to reduce stress
· Singing, Humming, Chanting, and Gargling
· The Vagus nerve is connected to your vocal cords, and the muscles at the back of your throat
· Singing, humming, chanting, and gargling can activate these muscles and stimulate your Vagus nerve
· Probiotics
· It’s becoming increasingly clear to researchers that gut bacteria improve brain function by affecting the Vagus nerve
· In one study, animals were given the probiotic Lactobacillus rhamnosus, and researchers found positive changes to the GABA receptors in the brain, a reduction in stress hormones, and less depression and anxiety-like behavior
· Meditation
· Research shows that meditation increases vagal tone (activity of the Vagus nerve) and positive emotions and promotes feelings of goodwill towards yourself.
· Another study found that meditation reduces sympathetic ‘fight-or-flight’ activity and increases vagal modulation
· Omega-3 Fatty Acids
· Omega-3 fatty acids are essential fats that your body cannot produce itself. They are found primarily in fish and are necessary for the normal electrical functioning of your brain and nervous system
· They are critical for brain and mental health and affect so many aspects of wellness.
· They have been shown to help people overcome addiction, repair a ‘leaky brain’, and even reverse cognitive decline
· Researchers have also discovered that omega-3 fatty acids increase vagal tone and vagal activity
· Studies have shown that they reduce heart rate and increase heart rate variability, which means they likely stimulate the Vagus nerve
· High fish consumption is also associated with enhanced vagal activity and parasympathetic predominance
7. Exercise
· Exercise increases your brain’s growth hormone (BDNF), supports your brain’s mitochondria, and helps reverse cognitive decline
· Many brain health experts recommend exercise as their number one piece of advice for optimal brain health
8. Massage
· Research shows that massages stimulate the Vagus nerve, and increase vagal activity and vagal tone
· The Vagus nerve can be stimulated by massaging several specific areas of the body.
· Foot massages (reflexology) have been shown to increase vagal modulation and heart rate variability and decrease the ‘fight-or-flight’ sympathetic response
· Massaging the carotid sinus, an area located near the right side of your throat, can stimulate the Vagus nerve to reduce seizures
9. Socializing and Laughing
· Socializing and laughing can reduce your body’s main stress hormone
· They are likely doing this by stimulating the Vagus nerve
· Researchers have discovered that reflecting on positive social connections improves vagal tone and increases positive emotions
· Laughter has been shown to increase heart rate variability and improve mood
· Vagus nerve stimulation often leads to laughter as a side effect, suggesting that they are connected and influence one another
(How to Stimulate Your Vagus Nerve for Better Mental Health, January 21, 2017, Jordan Fallis)
This is another example of how to gain control when everything is out of control. You have the power to tell your body and mind what to do. By stimulating the Vagus nerve, you can send a message to your body that it’s time to relax and de-stress which leads to long-term improvements in mood, well-being, and resilience. This is a skill we need to master to help us move through this time of great stress. Your brain and body have been created to take care of you.
References:
Allied Services Integrated Health System. (June 23, 2020). The Vagus nerve: your secret weapon in fighting stress. Retrieved from https://www.allied-services.org/news/2020/june/the-vagus-nerve-your-secret-weapon-in-fighting-s/
Fallis, J. (January 21, 2017). How to stimulate your Vagus nerve for better mental health. Retrieved from: https://sass.uottawa.ca
Saladin-Schulman, J. (August 27, 2018). Vagus nerve overview. Retrieved from: https://www.healthline.com/human-body-maps/vagus-nerve#stimulation
