Now I’m not saying I believe what this guy is saying, but in direct response to your question, wheat, the primary source of nutrition for all of the Middle East at that time is susceptible to a fungus called ergot which produces and alkaloid very closely related to lysergic acid. So if this was occurring, then mass hallucination is not beyond the realm of possibility.
Green mulberry berries will also make you hallucinate, while you’re convulsing.
There was a case of ergotism in France a few decades ago (Hoffmann thought it was mercury poisoning, but most thought it was ergot on rye), and the people acted crazy for a while, but I don’t think anyone thought it was divinely inspired.
OK, let's assume there was a mass hallucination at Mt. Sinai. Why, then, would the Bible indicate that G-d said that no other nation would EVER receive a national revelation like Israel did at Mt. Sinai? What is the point of saying this? If you were Moses, or Moses and a bunch of close confidants trying to start up a new (and lucrative) religion, WHY would you put something like that in the text? Because, you see, if only ONE thing in the entire text is wrong, then it isn't the Word of G-d, it is just a bunch of crap, end of religion. That claim is not only unnecessary to the text, but it (claims made in the future) is something that cannot be controlled by any humans.
Oh, BTW, in the last 3,300 years, not one nation has made a claim of national revelation. That's not "never," but its a pretty good record, wouldn't you say?
“ergot which produces and alkaloid very closely related to lysergic acid.”
As I recall, the Dancing Plagues?????
I've never read any evidence to suggest there even is such a thing as mass hallucination. Each person's hallucination is 'individual'. . .like dreams.
Just imagine, this 'mass hallucination' would have to come to a large group of people all at the same time, and that this would have had to happen multiple times.
Sorry, just not possible.