Yoga Research Foundation

Scientific Research into Swara Yoga (Part 2)

Dr Swami Mudraroopa Saraswati


Swara yoga in psychiatry and neurology

Recently, interesting findings, related to swara yoga postulating the mental aspects of ida and pingala nadis emerged as a result of the study published in the International Journal of Developmental Neuroscience in 2007.*44 Hand, eye and nasal airflow dominance were studied in 37 autistic children and compared with a control group of 20 children. The autistic children showed strong left nasal dominance, breathing predominantly through the left nostril, while in the control group balanced alternate nasal dominance was present. The authors conclude that, "Autism and early language impairment may be associated with left-handedness, left-eyedness and nasal dominance . . . These results show that the patients with autism had no normal nasal cycle; they probably had almost continuous left nasal breathing."

In yoga physiology, autism is understood as a state of imbalance in which ida nadi is far too overactive and children become overly introverted. The state of imbalance presents itself as the predominant airflow through the left nostril. Implications of these scientific findings point to yogic measures that can induce the state of balance in the ida-pingala system: Surya bheda pranayama activates the breathing pattern through the right nostril, pingala. By activating the extrovert human nature, this gradually brings about a state of harmony. Also, autistic children can be taught padadhirasana with the right hand tightly pressed against the left armpit. Matsya kridasana on the left side of the body with the right knee bent would further benefit those children. Both of these asanas stimulate pingala.

Studies have been carried out on the use of surgical vagus nerve stimulation for the control of drug-resistant epileptic seizures, and the effectiveness of this method is recognized, but there are side effects to consider.*45 Experimental and human studies strongly suggest that the anti-seizure effects of vagus stimulation are mediated through the reticular activating system, the limbic system and central autonomic network. Vagus, as the principal part of the parasympathetic nervous system, is controlled by ida nadi. Therefore, the use of chandra bheda pranayama to gently stimulate the vagal nerve in a natural way, without any side effects of surgery, may help in difficult cases of epilepsy.

Swara yoga in ophthalmology

Unilateral right nostril breathing, equivalent to surya bheda pranayama and practiced for 20 minutes continuously, was shown to reduce intraocular pressure by 25% in glaucoma simplex (both open and closed angle glaucoma) in 46 out of 51 patients.*46,*48 All patients were under standard pharmacological drug treatment, and several had also undergone surgical treatment also in the past. Lowering of intraocular pressure was significant and happened in both eyes. Patients that did not respond had juvenile glaucoma and a neo-vascular type of glaucoma that seriously limit the flow of ocular liquid in the eye. This study shows fascinating autonomic nervous system regulation of ocular pressure by surya bheda pranayama. What is more, there is evidence that this reduction is of the same magnitude in both healthy people and patients suffering from glaucoma.

Yogic effects are almost immediate and in the range of up to 30-35% of reduction, while pharmacological effects take 20-30 minutes and are in the range of 15-35%. What remains to be done is to investigate the exclusive use of surya bheda without the use of drugs as a possible treatment for glaucoma. Although during this study the effects of surya bheda lasted for 2-3 hours, there is the possibility that by sustained daily practice its influence on intraocular pressure would become even more stable and prolonged. Also, there are some preliminary findings of increased right nostril obstruction by nasal polyps in patients suffering from glaucoma, indicating that insufficient right nostril flow may be a contributing factor in this disorder.

Swara yoga in cardiology

Raghuraj and Telles in 2008*47 presented the results of surya and chandra bheda and nadi shodhana pranayamas on blood pressure, compared to simple breath awareness and natural breathing. Each session of breathing practice lasted for 30 minutes, followed by 10 minutes of quiet sitting. Following surya bheda, there was a significant increase in systolic, diastolic and mean pressure. In contrast, the systolic and diastolic pressure decreased after nadi shodhana and the systolic and mean pressure were lower after chandra bheda. Hence, unilateral nostril yoga breathing practices appear to influence the blood pressure in different ways. These effects suggest possible therapeutic applications, indicating that nadi shodhana may be the best choice for long-term management of high blood pressure (HBP), and surya bheda as a tool to rectify a tendency towards low blood pressure.

In 2007, the Yoga Research Foundation conducted a study on 30 hypertensive adults and it was found that the practice of nadi shodhana pranayama for one month with the ratio 1:1 (inhalation - exhalation), without holding the breath, brought down both systolic and diastolic pressure by an average 14.5 mmHg and 4.2 mmHg respectively.*50

Yogic tools for quick change of swara: matsya kridasana, padadhirasana, and yoga danda, and nostril airflow

Research conducted by ENT specialists Haight and Cole in 1984-1986 *40-*43 and published in American journals of otorhynolaringology showed through a series of complex experiments that adopting the posture equivalent to matsyakridasana leads to significant changes in the nasal airflow, resulting in decongestion and consequent increased airflow through the upper nostril and at the same time to congestion and decreased airflow through the lower nostril. Progressive lengthening of the time spent in this asana increased the magnitude of nasal response and it endured for longer.

They reported that nasal changes occurred in 37 out of 42 subjects and concluded that the efferent pathway for these vasomotor reflex responses is via the sympathetic fibres to the erectile tissue of the nasal mucosa, and that the receptors are located deep in the subcutaneous tissue of the chest wall but superficial to thoracic organs. They concluded that the pressure-sensitive zones are located in the ventral, dorsal and lateral aspects of the pelvic and pectoral girdles and thoracic wall. They also state that, "This topographical distribution is strikingly similar to that which induces contra-lateral sweating in response to localized pressure, the 'hemi-hydrotic reflex'. Therefore, there is a possibility that these responses share a common afferent pathway."

In addition to this, researchers observed that at least in some people nasal dominance shifts due to asymmetrical weight distribution while seated. The implications are to be considered when perfecting a sitting asana for the advanced practice of pranayama. An uneven weight distribution in the asana can interfere with the natural swara rhythms.

Others studied the effects of sustained pressure in the armpit that also extends to the reflex point in the fifth inter-costal space on the frontal chest wall. This is the kind of pressure achieved through the use of a yoga danda, a wooden armrest designed by yogis to exert pressure in the described areas of the body in order to facilitate pranayama practice. Also, the same kind of pressure is applied by the hands and thumbs in padadhirasana, an asana that is used to alter the swara. A study published in the Journal of Applied Physiology *49 revealed that, "Pressure in the axilla, armpit, can induce changes that lead to decongestion and increased airflow in the contra-lateral nostril." To prove that this particular pressure in the armpit is responsible for the nasal flow change, researchers positioned subjects in such lying positions using two separate tables so as to free the lower neck, shoulder and hand from any weight or pressure, and in that position no change in the nasal airflow was found.

In addition to these findings, we can add that pressure in the armpit and more specifically at the fifth inter-costal space on the frontal wall of the chest and consequent increase in the nasal airflow in the opposite nostril can easily be understood from the point of view of Chinese acupuncture. The point of origin of the lung channel on the frontal chest wall is being stimulated by pressure, especially by the thumb in padadhirasana. The lung channels from the left and right side of the body intersect with each other above the upper lip, only to end with their last acupuncture points just near the nostril opening on the opposite side. Therefore, stimulation of the left lung channel will result in opening of the right nostril and vice versa.


So far, scientific research indicates that substantial changes in the body and mind can be achieved using the techniques of swara yoga. Basic research studies directed the attention to probable mechanisms that connect the nasal breathing cycle and pranayama techniques with the limbic system and further on to the higher brain structures in the cortex. Other more pragmatic researchers demonstrated that higher cognitive faculties of the left and right brain hemisphere and the overall regulator of psychophysiological homeostasis in the body, the autonomic nervous system, can be effectively influenced by pranayama practices. Potentially far-reaching consequences of fine-tuning the sympathetic and parasympathetic nervous systems have been observed. Changes in blood chemistry, in the blood levels of stress hormones and insulin, in blood pressure, in EEG readings and in sleep patterns have been reported. They also proved that additional tools of swara yoga, postures like padadhirasana and matsya kridasana, can alter the nasal cycle, which has been shown to be a unique marker of autonomic nervous system activity.

Further on, the possible therapeutic use of pranayama in the management of various disorders in diverse fields of medicine, such as psychiatry, neurology, endocrinology, cardiology, ophthalmology and others, has been analysed and found significant. So far, autism, epilepsy, compulsive-obsessive disorder, high and low blood pressure and glaucoma have been shown to benefit from chandra bheda, surya bheda and nadi shodhana pranayamas.

There is sound scientific evidence that by adopting simple yoga postures such are matsyakridasana and padadhirasana, one can quickly and effectively manipulate the swara and through it the whole autonomic nervous system. In the course of time other yoga practices which exhibit similar effects, like the purification practices of jala and sutra neti, should receive attention from researchers.

We need both ida and pingala, and we need them awakened and in balance with each other. Then we can glide between the two domains effortlessly and naturally, adjusting to circumstances and meeting the challenges of life in a balanced way, keeping good health, mental poise and a harmonious evolution of our personality.

Left nostril Right nostril
Right hemisphere Left hemisphere
Introversion Extroversion
Mental and artistic work Physical and dynamic work
Metabolism slows down - cool Metabolism speeds up - warm
Interprets emotional connotation of communication Use and meaning of words and language, both spoken and written
Recognition of facial expressions  
Intuitive, integrative, accurate Rational decisions, thinking judgment
Music and art awareness, imagination Logical, verbal, mathematical, analytical
Perception of space, patterns, direction  
Parasympathetic Nervous System Sympathetic Nervous System
Management of: Management of:
- epilepsy  
- obsessive compulsive disorder - glaucoma
- high blood pressure - low blood pressure


Research into the field of swara yoga and pranayama encounters certain challenges. A good number of researchers think that the extent of the psychophysiological response of their subjects to pranayama techniques may significantly depend on their proficiency in yoga practice.

This observation should be taken into consideration when evaluating research data in a practical sense. Definitely, the manner in which one does pranayama greatly influences its effects on the body and on the mind. By its nature and essential mechanism, pranayama is more psychic than mental, and more mental than physical. One uses the medium of the physical body to manipulate the breath in a specific and prescribed way, but that is just a preliminary though necessary step. The main objective of pranayama is to access the psychic energy network of prana, the essential energy of our psychophysiological metabolism, and in this context we use the breath to connect our physical body with our energy and psychic bodies. The better we connect with these realms of our being in which prana flows freely, the more prana will be filtered down to the physical body, and more tangible effects on our brain and nervous system will happen. The key to unlock this process is the refinement of breath awareness in pranayama. Easy to say, but how to achieve this? This refinement of awareness spontaneously happens in the process of yoga, using various and integrated yoga practices and techniques from diverse branches of yoga, and not just pranayama. It is also a natural outcome of taking yoga with us into our life and lifestyle, as happens naturally in Satyananda Yoga. As one moves along this path, one definitely becomes more aware of subtle energies within the body and the mind, and then they wake up and the effects of pranayama reach deeper and deeper dimensions of our being.

One should not become discouraged by these facts. On the contrary, this knowledge should be used as an assurance that the right path and course of action in perfecting one's yoga can lead to deeper changes in ourselves.


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In Part 1 of this article, page 39, lines 12-16 should read: Yogis investigating the science of swara yoga have discovered that the activity of ida nadi, the right brain, correlates to the airflow in the left nostril, and that pingala activity correlates to the airflow in the right nostril.