No idea at all. But I am reminded about something that my old martial arts teacher said once. He is a true master not an american with a black belt. He asked during one class if anyone wanted to get a visit from their grandfather. By this he meant, did anyone want to volunteer to be choked until he lost consciousness. He proceeded to talk about his old days training in Korea and how the students would choke each other in such and such a manner and how relaxing it was to be gone and come back. It happened to me once (getting choked) very briefly. I felt myself continuing to be at the level of my six feet height while my body was falling downward to the matt. I caught up with myself. Didn't see my grandfather (at least not that I remember). My two cents worth. stuart moore.