Melatonin is a hormone which is secreted by the pineal gland or ajna chakra. This hormone is said to enhance the quality of sleep, extend the duration of sleep and opens a hidden channel in the brain from where a gush of tranquility engulfs one's mind.
The amritham or ambrosia which is secreted when kundalini shakthi reaches the sixth chakra (ajna chakra) is termed as 'melatonin' according to science.
It's hard to believe that melatonin tablets can replace the Ultimate Bliss experienced by the kundalini yogis.
Medical research (into melatonin and methods of its enhancement) has concluded that slow, pleasant, essentially classical and instrumental music stimulates melatonin in a big way.
Playing the Veena of fine jackwood regularly, with spine erect and chin up activates kundalini shakthi. Regular practice of Veena in the correct posture, fine tuning of the instrument and flawless rendition activates kundalini (life-force energy).
The practitioner who is a spiritual aspirant need not dwell into fast or speedy phrases. Slow and long oscillations (gamakas), especially slow oscillation and sustenance of a swara or a note pulled from a previous swara (preferably from behind 2 or more swaras) cause the practitioner's breath to slow down while pulling the string and breath is suspended when the string is held at a certain degree of oscillation in order to touch the perfect jeeva swara.
Kundalini yoga attained through Veena playing taps the most evasive hormone, which is the actual melatonin.
SOUNDARYA LAHARI 36th SLOKA-
PARAM SHAMBHUM VANDEY PARIMILITHAPAARSHVAM PARACHITHAA
YAMAARAADHYAN BHAKTHYAA RAVISHASHISHUCHEENAAMAVISHAYE
NIRAALOKEYLOKEY NIVASATHIHI BHAALOKABHUVANEY!"
(The 36th sloka of Soundarya Lahari is for the activation of ajna chakra or the pineal gland).