Hummingbirds are a mystery. They are incredibly small, and their hearts beat incredibly fast. All zoological precedent should dictate that their lives be drastically short. However, these bright little birds defy biological science by living five times the length their heart-fluttering physiques should imply.
Why? It may have something to do with their ‘resonance’. Hummingbirds ‘vibrate’ while hovering at around 50 HZ. And resonance (as we shall see) can strongly stimulate the vagus nerve. The vagus nerve is an incredibly important neural highway running throughout the lengths of our bodies. It is becoming increasingly clear that stimulating the vagus nerve, and improving ‘vagal tone’ can enhance and enrich both physical and mental health, improving everything from figure to lifespan. Described as “The self-care nerve”  and “The future of medicine”  , the vagus nerve could hold the key to an astonishing number of modern ailments. Learning to utilise its powers is surely a must for anyone who cares about their health.
What Is The Vagus Nerve?
“Vagus” in Greek means “wanderer” or “traveller”. It’s the perfect name for our eponymous nerve, which “travels” throughout the body, taking in more or less everything as it goes. It begins in the brainstem before heading down through the brainstem and into the front of the neck via the carotid artery sheath. It then proceeds into the body, incorporating on its route the cardiovascular system, the digestive system, the reproductive system, and many other organs taking readings from each and passing on to them –messages from the brain, like a neuronal superhighway. It’s by far the largest nerve in the body, and covers a stunning amount of ground. There’s very little going on in your internal organs in which the vagus nerve is not involved. Interestingly, it can also provide an alternative link between the brain and the genitals. Many with spinal cord injuries are still able to achieve sexual pleasure thanks to the vagus nerve.
The Vagus Nerve And The Autonomic Nervous System
We tend to think of the human nervous system as a singular entity. In fact, it is comprised of many interlocking elements. Of these, the most important for our purposes is the Autonomic Nervous System (ANS). The ANS controls ‘autonomous’ functions, i.e. those over which the human has little to no conscious control. Things like heart rate, blood pressure, sweating, digestion, the subconscious aspect of breathing and so on all come under the remit of the ANS. The ANS comprises three main elements: the Sympathetic Nervous System (SNS), the Parasympathetic Nervous System (PNS), and the Enteric Nervous System (ENS). The SNS is responsible for the so-called ‘fight or flight’ reaction. It is the SNS which causes our body’s instinctive response to danger, increasing the heart rate, pumping up the lungs, diverting blood from organs to muscles, flooding the body with oxygen, and triggering the release of adrenaline, and cortisol. The ENS is concerned with the function of the intestines (although digestion also has it’s own independent reflex activity) but also has a role to play in communication with the central nervous system. The PNS is responsible for what is sometimes termed the ‘rest and digest’ system. It calms the body, bringing down heart and breathing rates, re-diverting bodily resources to the vital organs, and allowing the deeper autonomous systems (such as digestion) to work at full capacity. The vagus nerve provides the vital communication highway by which these systems operate. It’s the ‘central switchboard’ of the ANS, if you will.
‘Fight Or Flight’, ‘Rest And Digest’
The Sympathetic Nervous System, though essential for survival, is not designed to remain active for long periods. However, when it is needed in an emergency it has to come on line immediately. Consequently, the SNS is always at the ready, held back only by the ‘braking’ effect of the PSNS. The ‘fight or flight’ reaction involves pumping up the muscles, giving the individual a shot of energy, and dulling the pain response. In theory, it should last only long enough to let the threatened person fight or flee their way out of a potentially dangerous situation, at which point it should be extinguished. In order to achieve this (theoretically) temporary ‘boost’, the SNS diverts resources from the organs and deeper autonomous systems in order to power the muscles and heighten the sensory responses. Needless to say, when inappropriately prolonged, a ‘fight or flight’ state does the vital organs no good at all. Sadly, modern stressors are not as transient as the threats our SNS evolved to protect us from. Our SNS cannot distinguish between physical and psychological distress  , so the more transient stressors of the modern age frequently leave people in a prolonged and highly damaging state of persistent low grade ‘fight or flight’. In order to combat this and gain a state of physical and psychological health, we must to bring the body back to a more natural resting state of ‘rest and digest’. This can be achieved through stimulation of the vagus nerve.
Parasympathetic Vagal Response
Stimulating the vagus nerve can ‘wake up’ the Parasympathetic Nervous System. This will then go to work in various beneficial capacities. Stomach acid and digestive enzyme production will be increased, ensuring the proper and sustained absorption of vital nutrients. Blood pressure will be lowered. The immune system will be properly regulated. Hormones and enzymes like oxytocin and acetylcholine will be stimulated, aiding the body’s general health and improving psychological wellbeing. Nor does it stop here. Studies have demonstrated that the vagus nerve is capable of taking readings from the micro-biome, and initiating inflammation-modulating responses depending upon the results of its findings  . Further, it will mobilise anxiogenic (anxiety-causing) and anxiolytic (anxiety reducing) effects in response to certain stimuli, indicating the powerful potential for mood-alteration inherent with vagal nerve stimulation  . There is even a school of thought which holds that learning to control one’s vagus nerve enables one to control inflammatory responses  , effectively slowing cellular breakdown and reducing the effects of ageing. Needless to say, this is a far better alternative to treating pain and inflammation than often dangerous analgesic and anti-inflammatory drugs  . Some have taken this anti-inflammatory theory further, positing that the vagus nerve can ‘plug’ into the body’s latent stem cells, implying that one can not only slow cellular decay via the vagus nerve, but can actually stimulate a degree of cellular regeneration.
The efficacy with which an individual can stimulate their vagus nerve depends greatly upon their vagal tone. The term ‘vagal tone’ refers to the strength, speed, and efficiency of the vagus nerve response. This can be tested via an electrocardiogram, which measures the differential between heart rate during out and in breaths. A high differential indicates high vagal tone.
Improving Vagal Tone
High vagal tone is associated with more efficient blood glucose regulation, indicating a far lower risk of diabetes, stroke, cardiovascular disease and so on. Low vagal tone, conversely, is associated with chronic inflammation, raised stress levels, and cardiovascular problems among other things. One’s vagal tone can be improved by practicing the stimulation of the vagus nerve. There are various ways in which this can be achieved, some more invasive than others. Since 1997, those suffering from conditions like acute migraines and epilepsy have sometimes been treated by the implantation of a Vagal Nerve Stimulator (VNS). This works by using electric currents to stimulate the nerve, and patients frequently report an improvement in both physical and psychological health, as well as a significant reduction in seizures and/or migraines. It is also widely accepted that the use of a VNS can be useful for depression, bipolar disorder, and morbid obesity 
Non-Invasive Vagal-Nerve Stimulation
The nerve can also be stimulated through less invasive procedures, with only slightly less dramatic results than those gained via a VNS. For example, stimulating the nerve via carotid sinus massage is also proven to suppress some kinds if seizure and to reduce rapid heart rate  . Certain yogic techniques can also feed psychological information ‘backwards’ to the brain via the vagus nerve. Just as psychological stimuli can cause a bodily ‘fight or flight’ reaction, so physical information can influence a psychological reaction. The conduit along which this information travels is the vagus nerve. By mimicking the symptoms of calm through things like yogic breathing and smooth movements, one can encourage the vagus nerve to feed back to the mind that all is well. The psyche, consequently, allows its stress to seep away.
Humming And Hawing
One of the most interesting methods of stimulating the vagus nerve involves auditory vibration. Humming and rhythmic chanting have long been acknowledged meditative techniques, and are proven methods of stimulating the vagus nerve  . Gently expressed binaural sounds, ideally heard through headphones, also engage a parasympathetic vagus nerve response. Indeed, the intriguing subject of Auto-Sensory Meridian Response (ASMR)  may be connected to the activation of the vagus nerve in response to binaural sounds.
Vagal Tone Exercises
In terms of practical improvements, practicing self-caring meditative techniques are among the most effective non-invasive methods of improving your vagal tone. If you are looking for ideas by which you can improve your own vagal tone, you will find a few suggestions below:
- Humming. As mentioned, humming has a strong effect on the vagus nerve. Try combining humming with yogic/meditative breathing. Take deep, slow breaths in through the nose, and hum as you slowly breathe out. Focus on the vibrations of your hum in your ribs, your throat, your mouth and your cranium. Repeat until you feel relaxed. Communal singing, choir or prayer are also known to be beneficial, as is Gargling.
- Cold Water. In cases of high heart rate, you can stimulate your vagus nerve to bring the heart rate back down through the simple method of plunging your face for 30-60 into icy water. This promotes what is known as the ‘diving reflex’, during which the vagus nerve orders your heart rate to slow in order to conserve oxygen. The Dive Reflex, originally noted in cold water diving, is a first rate vagus nerve stimulation method capable of rapidly chilling down anxiety, panic, stress and body-wide inflammation as well as elevating moods. A large zip-lock plastic bag filled with ice or ice cubes applied to the face from the scalp line to the lips will perform as well.
- Meditation. The vagus nerve can be powerfully stimulated by calming and centering oneself via meditation. There are many meditative techniques, some active, some passive. Choosing the right one for you is largely a matter of trial and error. However, when you find one which works, consistently practiced meditation will quickly improve your vagal tone.
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About the author
Stefan Chmelik has spent a lifetime in natural health and 30 years as a practitioner. He is founder of New Medicine Group, the UK’s premier integrated healthcare team, and is now focussed on his new company BioSelf Technology, who are developing SENSATE – wearable technology to enable anybody to experience the many benefits of relaxation on demand in the shortest possible time.