I have a that to a slight degree, but i look at it more as opening my mind, after weed you really question things and think out of the box, out of reality, and more in an intellectual fashion, at least to me and a couple others I know. I think "psychosis" is just a scary connotation of "insight", its just a different insight into life after smoking weed, no mental illness like it might claim to be. Don't worry about it, there are many old, experienced stoners and the ones I've met all seem very wise, open minded folks.