Dream Herbs
Some cultures around the world use dreams to communicate with the spirits of their family.
When one begins to dream, the physical body is left behind, and the spirit is now free to travel to another dimension.
These rituals (lucid dreaming) are induced using dream herbs. The herbs are usually consumed just before going to sleep.
Lucid dream:
In a lucid dream, one is aware that they are dreaming; the term was coined by a Dutch psychiatrist.