i have been thinking about this, but lets get history about this too.

back when there were still tribes some tribes used forms of drugs to communicate with the higher above(they could do this and we cant cause we dont have the right genes for this, i am against every form of drugs...), what if this reaction has the negative side.

demonic possesion, if you read the bible and if that demon is inside you it will flip and well kill everything before it dies itself.

and well it does this, it is also possible that the demon just stays and become a lot stronger by some other reactions for a full take over you can say.

there will be more people and more that will turn into this, cause everyone has some powers inside him/herself and well if it awakens wrong, these things can happen. (those people can be mediums but not knowing themselves).

this is an interesting thing to think about xD.