Strange fantasy

Yes all sorts.  My only explanation is, just like meditation, the heightened awareness coupled with mental release allows for the brain to tap into a the realm of dreams. I would love to have my brain scanned, to see what is really happening while I get into these states.  I don't see specific a geographic location (though I recall a thread of people talking about this), nor do I have a single reoccurring vision. However, I have incredibly intense images arise in my brain during sex and prostate play.  The more I have gotten into prostate play, the more these strange hallucinatory moments happen during any and all sexual acts.  I have especially vivid images occur during touching/caressing sessions. That is, when my partner uses their fingers/hands/lips/etc. in every possible way, from tickling to gentle caressing to scratching and pinching and biting and sucking and so on, all over my passive body (or my writhing body), but not on my penis.  Most recently, as I was being "tortured" (I can't even say what was happening actually, but it involved teeth, sharp fingernails and my legs and feet), I had horrendously vivid images of myself as a sort of swamp monster, a gollum of sorts, bug-eyed and twisting.  This is not something I find sexy normally-- I could not care less for sci-fi fantasy sex play-- but in the moment it was fascinating to see such clear images in my mind.

Yes, I've had those visions along with faces from the past of girls I've really fancied or been turned on by, not long visions but a quick flash, its sureal.