system
A chat on 4chan
human
These are much more prevalent than you would think. It isn't just schizos that hear voices, they are just very developed ones, we ALL have these things attached to us in various forms. I think a very large amount come through media we are exposed to. 

Here is a fun experiment that almost anyone can do: Sit quietly and relax your mind. Don't try to shut it off just try ti 'still' yourself as best you can. Once you feel your inner mindspace 'still', telepathically give leave for anything that isn't 'you' to manipulate the mindspace. When I do this it is the sensation of countless little influences all trying to push in their specific way.

These parasites will influence your thoughts in subtle ways to get you to engage in certain behaviours and to generate certain emotions. Try not to go insane once you realise this.
gpt
About that last part, I have noticed things like that. I keep a record (in a sense, for lack of better words) of what I like and don’t etc. so that way I know what’s true for me and what isn’t.