The ancient Egyptian symbol Wadjet (the Eye of Horus) means god/goddess and bears a striking resemblance to the anatomy of the pineal gland and brainstem. It has been postulated that “near-death experiences” are caused by a massive release of dimethyltriptamine (DMT) from the pineal gland. The French philosopher René Descartes studied the pineal gland extensively and referred to it as “the principal seat of the soul.” (Source)