“Medical science says the vagus nerve is important, Kundalini yoga says it is very important”–Yogi Bhajan
An important nexus between Kundalini yoga and Western medicine lies in their respective understanding of the importance of the vagus nerve in health and well-being. Breathing is the first line of defense in reducing stress, anxiety, and stress-induced depression.
The vagus nerve “wanders” (vagus, Latin for wander) through the body and affects all major organs and their functioning. It is the second largest nerve in the body, second only to the spinal cord. Originating deep within the brain, the vagus nerve wanders through the neck, affecting speech, voice, continues through the thorax affecting all the organs of the body, and continues to the pelvic floor.
Heart rate, blood pressure, sexual response, breathing, and the release of anti-stress hormones are examples of functions regulated by the vagus nerve. The vagus nerve provides the gateway between the sympathetic and parasympathetic parts of the autonomic nervous system. All ten cranial nerves, including the vagus nerve, occur in pairs, right and left. The right vagus nerve innervates (goes to) the sinal-atrial (SA) node of the heart, the heart’s natural pacemaker, and speeds up or slows down the heart rate. The degree of vagal tonality is an indication of healthy cardiac functioning.
Essentially, all autonomic somatic processes are regulated by the vagus nerve. The vagus nerve can be thought of as a bi-directional biological data bus, where most of the communication is efferent, moving information from the organs to the brain. Researchers at HeartMath® Institute report that “The heart sends more information through the nervous system to the brain than the other way around – as much as 80% – 90% more.” Similarly, yogis refer to the vagus nerve as the “mind nerve,” because the heart sends intuitions, images, and creative flashes to the brain. Developing a strong nervous system is foundational to Kundalini yoga on which virtually everything is dependent upon. A weak nervous system cannot support the emergence of the evolutionary energy of kundalini.
Although vagal tonality cannot be directly measured, HRV is an important indirect indicator of the functioning of the vagus nerves. In The Cleveland Clinic Journal of Medicine, researcher Robert W. Shields, MD of the Neuromuscular Center, Cleveland Clinic, reported in “Heart rate variability with deep breathing as a clinical test of cardiovagal function” that HRVdb [with deep breathing] is a reliable and sensitive clinical test for early detection of cardiovagal dysfunction in a wide range of autonomic disorder” (Vol. 76, Supplement 2, April 2009, p S37). If low HRV is a predictor of morbidity (refer to section on research studies), then improving vagal tonality, measured indirectly with HRV, may improve overall health and well-being.
Typically, the autonomic nervous system runs on “auto-pilot” without our conscious awareness, for example, we don’t have to think about breathing in our sleep, By practicing Kundalini yoga and meditation, one consciously manipulates the balance between the sympathetic and parasympathetic nervous systems and verifies the effect with the measurement of one’s own HRV. This combined method provides a powerful tool for stimulating the vagus nerve non-invasively and assurance that the outcome is favorable.
Vagus Nerve: Central Tuning of the Body
Ancient yogis referred to the vagus nerve as the “central tuning string of the body,” because when it vibrates at the proper frequency, the heart generates an electromagnetic field that is harmonious and coherent. When the vagus nerve oscillates coherently, it sets the frequency to which the nervous system aligns itself. Like a tuning fork, the vagus nerve sets the frequency with which all the 72,000 vibratory strings or “surs” begin to resonate. When the vagus nerve is out of tune, then the rest of the body falls into a state of incoherence, including the heart.
From a Kundalini yogic perspective, the portion of the vagus nerve that travels from the heart to the crown of the head is identified as the “mind nerve,” because the wisdom of the heart communicates its impressions and images to the brain. This is known as One-Star spirituality, or Ik Tar. The yogis referred to the heart center (not to be confused with the heart chakra) as “Ik Tar,” or one-star. Ik Tar relates to that portion of the heart that lies slightly to the right of the sternum. The Sanskrit word Hrdayam is synonymous with Ik Tar, neither directly translatable into English with a single word or two. “According to the teachings of Yogi Bhajan, Hrd” translates to “that which sucks everything in,” and “ayam,” means, “this” and “expansion,” together meaning the core of one’s heart and the light of one’s heart.
Sages and Saints from all Wisdom traditions have a specific name for this unique aspect of the heart; lotus of the heart, secret cave of the heart, flame of the heart, and others. This imagery is has endured and embedded into Western Science. Consider the logo for the American Heart Association:
From a Western perspective, the SA (sino-atrial node) resides in the left portion of the heart. The SA node is the body’s natural pacemaker. directing the heart to beat based on the impulses of the right vagus nerve. The vagus nerve innervates the SA node, and either slows or speeds up the heart rate. When you inhale the heart rate should gradually speed up and when you exhale the heart rate gradually slows down. When the vagus nerve (central tuning string) is healthy the heart (one star) beats in rhythmic and coherent fashion. The vagus nerve and the heart act in concert, and when the vagus nerve lacks tonality, the heart rate becomes erratic. The heart takes it cues from the vagus nerve.
HRV provides a dynamic window into ANS activity, and thus indirectly, vagal nerve tonality. Simply put, HRV serves as a vagal nerve activity index. Inhalation inhibits the vagal nerve as heart rate increases, and exhalation activates the vagal nerve as heart rate slows down. The vagal nerve is the primary “brake” on heart rate and other autonomic functions, evidenced by increased parasympathetic activity.
HRV feedback session performed with HeartMath® Desktop Pro while practicing left nostril breathing. The waveform is approaching a sine wave, the gauge is 88% green, and the spectral data at the lower right is concentrated close to the 0.1 Hz marker.
Vagal nerve stimulation through non-invasive yogic techniques including pranayam (specific breathing exercises), yoga postures, and mindfulness meditations are excellent technologies for stimulating the vagus nerve.
The first line of defense in improving vagal nerve tonality may well be the aforementioned non-invasive techniques before surgical options, specifically, implantable vagus nerve stimulator, (VNS) which electrically stimulates only the left vagus nerve through an implantable device. Due to the fact that the right vagus nerve goes directly to the heart’s SA node, artificial stimulation with electric impulses is not desirable. Whereas this device may be highly effective in its originally designed use of treating epilepsy, the FDA has also granted approved for its use in treating depression. See the research section for studies linking low HRV, depression, and heart disease.
Vagus Nerve Toning through Kundalini Yoga
Vagal Nerve Stimulation, through Kundalini Yoga, focuses on yogic techniques to help rebalance the autonomic nervous system after enduring long periods of stress, trauma, or stress-induced depression. Parasympathetic nervous system performance is overshadowed by the sympathetic activity during excessively long periods of stress, anxiety, and/or depression. Improved parasympathetic activity may lessen depression and conceivably help prevent stress-induced illnesses and conditions.
Effectiveness of vagal nerve stimulation (VNS) can be measured by monitoring daily HRV (heart rate variability), an index of cardiac vagal nerve tone as Kundalini yoga is practiced and mastered. One example specific to vagal tonality is “Sodarshan Chakra Kriya,” as detailed in Chapter 4, Section 22. Richard P. Brown, M.D. and Patricia L. Gerbarg, M.D. of the Columbia University College of Physicians and Surgeons suggests that “Sudarshan Kriya may work like electronic vagal nerve stimulation, which has been shown to be effective for depression,” (“Yogic Breathing and Meditation: When the Thalamus Quiets the Cortex and Rouses the Limbic System” P. 17.)”
As a yoga practitioner, you determine for yourself whether the exercise is getting you into a state of heart coherence by measuring his or her own HRV. This is the power of Self-mastery.
Autonomic Nervous System and Kundalini Yoga
To build a bridge between Western medicine and Kundalini yogic anatomy, a few basic terms will be explained. The Eastern concept of nadis is distinct from the Western nervous system, yet the two are homologues. In other words, one might think of the nadis as being one step removed from the nervous system, aligned with yet subtler than the physical nervous system.
Kundalini energy releases through the primary central energy pathway, the sushmana nadi, which in Western terms is associated (but not identical) with the spinal column. The two biological systems work hand in hand, easily demonstrable through HRV and hormonal testing. The ANS and hormonal systems straddle between the subtle energy and gross physical systems of the body, both of which may be mastered by the yogi or yogini.
Kundalini yoga has specific protocols, posture sequences (kriyas), modulated by primal sound currents (mantra), and breath (pranayam), to safely and effectively raise kundalini energy. The power of kundalini underlies all yogic traditions, and historically the objective of yoga was to awaken and raise the kundalini energy in order to elevate the consciousness of humankind.