Witches and LSD

While investigating the mass hysteria of the Salem Witch Trials, a behavioral psychologist at New York's Rensselaer Polytechnic Institute, noticed a link between the strange symptoms reported by Salem's accusers, chiefly eight young women, and the hallucinogenic effects of drugs like LSD.  And since LSD is a derivative of ergot, a fungus that affects rye grain, she began to suspect that their bread had been tainted.

Ergotism had indeed been implicated in other outbreaks of bizarre behavior throughout the ages. Perhaps, it may even explain those funny hats that witches wear?