What methods were used in the past to communicate with spirits and the unknown? We know that early Andean sorcerers used neurotoxins from various animals and plants to create the sensation of communicating with spirits. In animals, the neurotoxin is found in shellfish. In some areas, at a certain time each year, algae containing the toxin grow and turn the ocean bright red. This is a red tide.
The toxins accumulate in the shellfish that eat the algae, so when a red tide occurs, the shellfish become poisoned for some time. If a person eats that shellfish, poisoning symptoms can cause numbness, dizziness, feeling like flying, etc., and large amounts can kill the person.
In addition, eating the liquid secreted from the back of the toad's head can cause hallucinations, vomiting, diarrhea, heart attacks, and in the worst cases, death.
The most famous plant is the coca tree. Its leaves contain the narcotic cocaine. The coca tree may have been used as a local anesthetic when mixed with saliva to treat injuries.
What do "hallucinations" or "feeling like you're flying" feel like? Obviously, these are symptoms of mental derangement, but I would like to experience them for a while. In ancient times, when science had not yet developed, if you had a mental derangement during a sorcerer's ritual, you would think that you were really communicating with spirits, wouldn't you? I wonder if the ancient Andean sorcerers had a sensory understanding and mastery of the nature and proper amount of such toxins in nature.