This happens to my friend all the time. He has some freaky ass stories of feeling like something/someone getting on top of him, i.e. the pressure of another person and/or seeing something in his peripheral. Also, the feeling of paralysis and not being able to speak or make any sound other than murmurs, etc. He freaks us all out sometimes with the stories because he's a very artistic person (art, writing) so he's able to describe it in great detail. I've also walked in the room when it has happened to him before and I looked right at him because his eyes were wide open looking at me and his mouth was moving but he looked scared to death...it's just not cool.
And mostly he says it happens when he's on his back only, except there was one or two occasions I remember him saying he was on his side.
And mostly he says it happens when he's on his back only, except there was one or two occasions I remember him saying he was on his side.