Eating from this mushroom (called fly agaric) causes hallucinations. This has been known since antiquity.

Myristica fragrans fruit, halved, showing within the red seed (nutmeg) enclosed in its brown aril (mace).

Hallucinogens are chemical substances which temporarily change the way people see the world. Hallucinogens cause hallucinations. People no longer perceive reality as it is, but they see a reality that is distorted by their emotions. A person who is under the influence of a hallucionogen is said to be having a trip.

Hallucinogens have probably been used in the context of a cultic or religious function as long as there were humans.

There are different kinds of hallucinogens:

• Psychedelic drugs: these are the "classic hallucinogens"
• Dissociatives: They make people feel as if they were no longerpart of their surroundings.
• Deliriants produce a state of delirium, or confusion.