It is impossible to canalize and concentrate on the functioning of the mind if breathing is not adequately regulated. Breath is essential for the metabolic functioning of the body. It is also linked with the conscious mind. Since the mind is ever restless, it is extremely difficult to steady the wandering mind directly An efficient and easy way to control mental activity is concentrated perception of breath - svasa preksha.
Proper regulation of respiration by the conscious mind results in the development of the controlled activity of the mind. To stop the restlessness of the mind and canalize its functioning it is essential to be aware of breathing. Shallow, hasty and irregular (spasmodic) breathing must first be regulated to make it deep, slow, calm and rhythmic. Even in kayotsarga breathing is not stopped but made subtle.
Deep, slow and rhythmic breathing is an essential condition for regulating the mental process. Very slow inhalation and complete exhalation (by the use of diaphragm) is called dirgha svasa (deep breathing or diaphragmatic breathing).
Complete awareness of breathing and nothing else but breathing is the basis of svasa preksha. Attention can be kept focussed on a single point in the respiratory tract, e.g. nostrils, or it can travel the entire tract during inhalation as well as exhalation. Various facets of breathing such as movement of the diaphragm, rate of breathing and depth of breathing can conveniently become the object of svasa preksha.
Svasa preksha can be practised in two ways, through dirgha svasa and samavrtti svasa.
Dirgha Svasa PrekshaSamavrtti Svasa PrekshaAs already explained above, dirgha svasa is slow and complete exhalation and deep inhalation. The first step in this process is to regulate the rate of breathing by reducing the number of breaths per minute. Normally a healthy adult's rate of breathing is 15-17 breaths per minute (b.p.m.). By practising diaphragmatic breathing, this rate can be drastically reduced. Even casual practice can easily bring it down to 10-12 b.p.m. And further regular practice can reduce the rate to 6, 4 or even 2 or 1 b. p.m.
Regulation of breathing, reduction in its rate, and its rhythmic nature result in steadying the mind. Simultaneously urges and impulses, emotions and passions and their impelling forces - the primal drives - all become amenable to control. When the breath is shallow and its rate high, primal drives and passions are aroused, strengthening physical urges and emotions. Quick breathing acts as a vehicle for all these distortions. One can easily pacify passions by regulating one's breathing If one slows down the rate of breathing and commences rhythmic breathing, the intensity of passions is at once retarded. This is so because they are deprived of the vehicle and without transport they cannot make much headway. A practitioner of meditation will, in due course, be able to perceive in advance the onslaught of rising passions, and thus will be prepared to nullify their attack by resorting to dirgha svasa. The rising passions will then begin to subside. Thus by blunting the sharpness of their attack, a sadhak saves himself from being the victim of dreadful urges and emotions.
Breath is a reality of the present moment. Practice of svasa preksha leads the sadhaka to live with equanimity and imperturbation. He will also get rid of tension as a side benefit.
As stated above, Preksha Dhyana is the technique of seeing one's own self. Breath is the gateway to the self (consciousness). To commence the internal trip, one must pass through the main gateway of breath. And when mind and breath become inseparable companions, the journey begins. In theory breath is part and parcel of the self and so one can realize the goal of reaching the self via breath. In practice seeing oneself simply means perception of all aspects of breath by the conscious mind.
Like dirgha svasa preksha, samavrtti svasa preksha is also an important process of this meditational system. Here breath is exhaled through one (say, left) nostril and inhaled through the other (right). Then exhaling through the right, one inhales through the left. Throughout the process the perceptive mind is closely linked with the breath. As in dirgha svasa preksha, breathing is regulated to be rhythmic. By practising it regularly one can ultimately develop the inherent capacities of the subconscious mind such as extra-sensory perception, clairvoyance, etc.