Why do some hallucinogens cause universal hallucinations?

Hopes&Fears answers questions with the help of people who know what they’re talking about. Today we ask the experts about common visions while tripping on psychoactive substances.
Can you get high on art?

Hopes&Fears answers questions with the help of experts. We asked a neuroscientist, an art critic and a neuroesthetics specialist if we can experience a high—or something similar—from viewing art.

Witches, bread and LSD: how a poisonous mold may have caused hallucinogenic hysteria
Hopes&Fears speaks to historic gastronomist Sarah Lohman about how a bad trip caused by ergot could be the root of monster myths, demonic possession and the Walking Dead.
How do you know you're going to have a bad trip?

Hopes&Fears answers questions with the help of people who know what they're talking about. Today, we try to parse how to tell if you are going to have a negative psychedelic experience.