The Pineal Gland and the Third Eye

The popular identification of this centre with the pineal gland, and the associated claims that the gland is a vestigial third eye which can be activated, decalcified or opened, is a chain of modern accretions and deserves separating out. Descartes proposed in the seventeenth century that the pineal is the seat of the soul, on the anatomical ground that it appeared to be unpaired.

The pineal is in fact a small endocrine gland that secretes melatonin and regulates circadian rhythm, and it does derive embryologically from photoreceptive tissue, which is why some reptiles have a genuine parietal eye; that is the grain of fact behind the story. It does calcify with age, which is normal and has no known relation to consciousness. The tantric texts say nothing about it. Claims about activating the pineal are contemporary folklore, not Indian tradition, and some of the substances promoted for it are harmful.