The Salem Witchcraft Craze: A Case of Food Poising?

Witch hunting came to the colonies of the US with the Puritans and reached it's peak in 1692.
In the Salem witchcraft craze, it is interesting to note that mast of the bizarre, abnormal behaviour involved was manifested not by those accused of witchcraft but by their accusers. In the Salem case a group of people suddenly fell victim to convulsions, hallucinations, fits of screaming and other symptoms so typical of young people today. Then, by way of explaining such oddities, they accused others of having bewitched them. The question of the accuser's original bizarre symptoms remains: Assuming that they were not the result of witchcraft, what caused them?
In a description of the Salem incident, Deutsch (1949) attributes the symptoms of the eight girls who initiated  the incident to hysteria, a recognized psychiatric condition in which emotional stress gives rise to physical dysfunctions. Others have suggested that the girls "afflictions might have been simply faked, in order either to get attention, or to protect themselves from punishment in case their elders discovered that they had been dabbling in magic.
Later, however, as shown on History Television,a new and utterly different explanation was offered: that the symptoms of the original eight girls, along with those of the other Salem citizens who later made accusations, were the result of food poisoning The originator of this hypothesis, points out that the symptoms reportedly displayed by the Salem girls  are quite similar to those of convulsive ergotism, a condition caused by eating grain infested with the fungus ergot. Ergot grows primarily on rye, which was a major crop in seven-teenth-century Salem, and it thrives in cool rainy conditions--exactly the kind of growing season that "Salem had in the year prior to the witchcraft scandal. The evidence on which this report rests is the resemblance between the reported behaviour of the "afflicted Salem citizens and the recognized signs of convulsive ergotism. These signs include vomiting, diarrhoea, crawling and tingling sensations in the skin, dizziness, headaches, sensory disturbances, and severe muscular contractions--all of which are mentioned in the records of the Salem witchcraft trials. Most crucial of all convulsive ergotism involves hallucinations and perceptual distortions. (Indeed, one of the components of ergot is a hallucinogenic, alkaloid, closely related to LSD,so popular in the 1960.) At the Salem trials and of the most damning forms of evidence against the accused was Spectral evidence--that is, the accuser's reports that the accused had appeared to them in visions, usually in the act of choking, pinching, or otherwise abusing them. according to the report, these visions were the result of the ergot's action in the brain. The fungus created perceptual disturbances, to which the accuser's beliefs in witchcraft gave form and meaning.  Seeing something fearful, they read into it the thing they most feared--witchcraft--and thus sent twenty-two innocent people to their deaths.
Of course, this hypothesis has not gone unchallenged. Two other investigators claim that there is more evidence against the ergot theory than there is for it. In the first place outbreaks of convulsive ergotism have occurred almost exclusively in communities marked by severe vitamin A deficiency--an unlikely situation in Salem, which was well supplied with fish and dairy products, two sources of vitamin A. Second, convulsive ergotism tends to strike whole families-- all those using the infected grain supply--whereas in Salem the "afflicted" were usually the only members of their families to show any symptoms. Finally, the reported symptoms of Salem's "afflicted" and the known symptoms of  convulsive ergotism are by no means a perfect match. They claim that the Salem records contain no reference to vomiting, diarrhoea, of a livid skin colour, three of the most common symptoms of this disorder, and that the hallucinations reported by the accusers are quite unlike the typical perceptual effects of LSD-type  drugs. What the accusers claimed  to have seen were visions of fully formed people performing recognizable acts, , whereas the usual effect of LSD and related drugs is merely to distort objects that ae actually there, producing halos on the edges of things causing straight lines to be wavy, altering depth perception, and so on. On the basis of this evidence the Salem girls afflictions were symptomatic not of convulsive ergotism but of "demonic possession," a stereotyped behaviour pattern that--as the writers suggest but do not directly state--these young women adopted for psychological reasons, voluntarily or involuntarily. 
Other, more recent studies of climate indicators, diaries, court transcripts, and other records have supported the infected-rye hypothesis.