Personally I don't think those images are 'self-conjured' at all. A person might draw attention to themselves by trying hard to do something like that, but the spirits that show up to play god or 'guardian' with them are probably real spirits... whatever happens to be in the vicinity.

One of the devil's (by devil I mean any spirit not of God) main ploys is the idea that he doesn't exist. In the case of something like a familiar spirit that a psychic might get information from, the psychic is aware of that spirit but not always aware of the little influences that spirit can exert either on her or others which help bring about so-called predicted events, or knowledge of the past as the case may be.

The funny thing about psychics is that they never seem able to predict their own futures very well, let alone their demise.

When the Lord finally found me, on my knees and crying out desperately for him... he removed a few pretty nasty spirits from me that I had absolutely no idea were with me. They fought quite a bit coming out and though I never experienced it in my day to day life (though they may have only been with me a short time, the astral projection attempts I suspect), one would try to make me lurch and growl like a tiger and another was cold like death and shook all the time, felt like a cold dead skeleton inside me, really gross... that one was quite obvious and was only there for a day, was very noticable I could not eat anything because it did not like to eat. He simply touched me or something and that one was gone what a relief...Not kidding, it was quite an experience.

Jesus exorcised me. I picked up another one in a jaunt across the country once, wasn't aware of it's presence at all except I can say I was not my usual self... the Lord or an angel of his... I heard the angel say... 'i exorcise you in the name of Jesus Christ' and no kidding I was lifted up by it and spit like a snake as it came out. I felt much better afterwards needless to say. But at that time I was very much walking with Jesus and I think he used me as a vulnerable looking decoy to carry that spirit quietly from another place he did not want it to be. I was in a locked room when he took that one, must have been a reason for that is all I know. someday I am sure i will learn more about that incident.