There are many claims that magnets induce blood flow and heal the body but no respectable sources have proved this (as far as I know.) Also, I don't see what the electromagnetic force would do to the body. It guess could affect iron in the blood or electromagnetic pulses in the brain but I don't see how this would make hallucenations.
After looking for a whileI couldn't find many articles but I found this one
http://www.research.fsu.edu/researchr/issue2001/mice.html
I do not know how reputable a source it is but I will put it out there.
This one talks about the effect of magnets on rats. It says nothing about hallucenations, but then again they used rats so it would be hard to tell. But they subjected them to high levels of elctromagnetism which I doubt could be reproduced with simple magnets. It would need a powerful soure to induce it. So I will say that ordinary magnets will have no or very little effect.