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Traditionally, there are three types of trataka available for the practice. They are Antar trataka, Madhya trataka and Bahya trataka.
Antar Trataka
In this trataka, one has to experience as if he is gazing in between the two eyebrows (Bhrumadhya drishti) or heart, navel or any other such internal organ with closed eyes.
Madhya Trataka
In Madhya trataka, the practitioner still gazes on bhrumadhya or nasagra (tip of nose) or any near object made of metal or stone or even on Aum written on paper, or single dot in black colour, with open eyes.
Bahya Trataka
In this trataka, one has to fix the gaze on the distant object like Moon, rising Sun or illumined planet.
Technique of Trataka
Trataka is done preferably in padmasana (lotus posture) or ardha-padmasana on the ground. It can also be done in sukhasana (comfortable sitting posture) but with the straight back or spinal column. A lamp is placed in the level of the eyes at about one meter distance. Now with the relaxed mind one should gaze at the bright portion of the flame, without blinking, till tears appear in the eyes and roll down on the cheeks. This is the endpoint of trataka. After this, eyes should be closed gently. The practitioner then should sit quietly for 3-5 minutes and then open his eyes slowly. If required, one may repeat the technique once again. It is recommended that after this the practitioner should wash his face and eyes with water.
The duration of trataka from the beginning till the appearance of tears varies from person to person. It also depends on the state of mind of the individual. The duration of trataka is less if the practitioner is relaxed and if the practitioner is tensed or disturbed, he may take more time to finish. Generally, in normal individuals trataka is finished within 3-5 minutes. Some individuals have been observed to take even more than 12 minutes.
Physiology of Trataka
It has been found that soon after trataka is over, the parasympathetic predominance is established as indicated by lowering of heart rate and respiration rate as well as an increase in amplitude of plethysmogram (vasodilatation). That means a peripheral blood circulation is increased after trataka. Emotional balance or stability is restored and a degree of relaxation is increased as indicated by the production of well-modulated train of alpha frequency after trataka.
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