In his response to Edge‘s 2006 question, What is your dangerous idea?, Clifford Pickover suggests that we’ll be able to induce controlled visions of virtual worlds:
False memories may be implanted, temporarily overriding your real memories. This should be easy to do in the future — given that we can already coax the mind to create richly detailed virtual worlds filled with ornate palaces and strange beings through the use of the drug DMT (dimethyltryptamine). In other words, the brains of people who take DMT appear to access a treasure chest of images and experience that typically include jeweled cities and temples, angelic beings, feline shapes, serpents, and shiny metals. When we understand the brain better, we will be able to safely generate more controlled visions.
I can’t be the only one to find it odd that a particular drug (DMT) induces that particular list of visions: jeweled cities and temples, angelic beings, feline shapes, serpents, and shiny metals.