That's like, the transcendental object at the end of time. Which, I believe, Plato hypothesized so te idea goes back quite some time. Also a thing promised by religion, particularly the Judeo-Christian models of it. You know, exiting time and history, basically, to be one with the Lord. So the need has been there, however legitimate such a need based off what can provide it can be.
But who knows. The goal, apparently, was to make people think what they have never thought imaginable. The end of time just fits within that category. There are so many things clouding our perception of reality and what it is sometimes a dissolving of the ego via esoteric means is the only thing that might make sense sometimes.
While not proven, they thought the pineal gland was the seat of all this. That, during mystical experiences and other spiritual moments that the pineal releases its spirit molecule, causing the things that happen during said mystical moments. However, the action of, say, DMT, and any actual spirit molecule could be way different. It just isn't proven.
In some animals the pineal is the third eye. It used to be. And it's light sensitive (but not in humans). In human fetal formation the pineal originates on the roof of the mouth before migrating to the middle of the brain.
It used to be a third eye. Maybe it saw stuff. Hypothetically, if it were to be activated, you'll see things. Kind of a long shot but maybe that's what's going on. But that's not really true. Melatonin is the primary hormone of the third pineal eye. And, it does help regulate things related to survival as the primitive third eye in reptiles does.