It's fairly easy to trick yourself into hearing voices: as you're going to sleep, picture yourself watching a newsreader. Keep watching them talk. Eventually your brain starts to switch to sleep mode and you actually start hearing something. (Well, you might fall asleep first.) If you're conscious enough it'll surprise the heck out of you and then the voice will go away.
Given how easy it is to pull this trick on yourself, I'm not entirely shocked that some people find it possible without conscious effort. But I think the content is rather like dreams: sometimes it's just nonsense, sometimes it's like that idea that comes to you in the shower, but always part of your brain processing your waking experiences.
Given how easy it is to pull this trick on yourself, I'm not entirely shocked that some people find it possible without conscious effort. But I think the content is rather like dreams: sometimes it's just nonsense, sometimes it's like that idea that comes to you in the shower, but always part of your brain processing your waking experiences.