A yoga practitioner has a well developed pineal gland. The pineal gland is a small endocrine in the vertebrate brain. It produces melatonin, a hormone that affects the modulation of wake/sleep patterns and photoperiodic (seasonal) functions. It is shaped like a tiny pinecone and is located near to the centre of the brain, between the two hemispheres, tucked in a groove where the two rounded thalamic bodies join.
In yogic science it is called the ajna chakra - the third eye. The true function of this mysterious gland has long been contemplated by philosophers and spiritual adepts. Ancient Greeks believed the pineal gland to be our connection to the realms of thought. Descartes called it the seat of the soul.
This gland is activated by light, and it controls the various biorhythms of the body. It works in harmony with the hypothalamus gland, which controls the body's thirst, hunger, desire and the biological clock, that determines our aging process.
When the pineal gland awakens, one may feel a pressure at the base of the brain. This pressure will often be experienced when connecting to a higher frequency.
Eyes are said to be the extension of brain. But by the time one reaches at the age of 13 or 14, his pineal gland becomes vestigial or dormant. To overcome this degeneration, our mystics suggested the great technique called tratak.
It is important to practice this technique on the flame of diya filled with clarified butter (desi ghee) as the flames and fumes so produced, profoundly improve the functioning of the pineal gland.
In this video, the revered mystic master Anandmurti Gurumaa explains the influence of this ancient meditation technique called 'tratak'.

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