What is the Pineal Gland?

8. "The Third Eye"

The pineal gland has a long history of mystery, both to scientists and philosophers. Due to the light-sensing nature of the gland, some have called it "The Third Eye," and 18th-century philosophers, notably Rene Descartes, thought it to be the residence of the soul. Pseudoscience and mystical beliefs still maintain the importance of the pineal gland beyond the regulation of the circadian cycle. Scientists long believed the gland to be a vestigial organ like the appendix, although later research finally discovered its melatonin-producing role.

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