I sat yesterday evening for my usual 1 hour.  Often I find my awareness identified and lost in a sea of papanca until I catch it and gently continue noting, or return to the breath.  However last night, for about 25 minutes during the sitting time it seemed as though I was in a place of nothingness.  No awareness of anything.  Unconsciousness.  My noting which was quite fast to begin with, then slowed done to the point where I slipped into this state of nothingness.  It concluded with a really strong energy flash which seemed to travel from my head downwards through my whole body.  The flash was so strong that it caused my arms to jerk and my eyelids to open.  A kind of energy explosion.  I've had this energy flash experience many times though for some reason the fash usually travels upwards from the base of my spine through the top of my head.  From the time of the flash my awareness and concentration returned to being shallow, like it is at the beginning of a typical meditation session.  The period of nothingness was like being asleep.  Time seemed to stop.  When my timer rang it felt as though the whole session was less than 1 hour because I couldn't account for the void.  During the void, noting ceased altogether.  I am wondering whether (i) I was so identified with papanca that I was no longer mindfull and forgot that I was meditating, and later couldn't remember the thoughts OR (ii) I was asleep and the energy flash was simply my body rejecting the sleep mode (I was sitting upright) OR (iii) a samatha jhana.  I've read enough to know that Vipassana requires continual awareness, albeit very subtle at the higher strata of consciousness.  Thank you for your comments.  Namaste.

Darin,

To me, this sounds like the experience of the 7th Jhana, Nothingness, which it seems you slipped into at some point. Can you remember if you kind of "decided", or willed yourself, to enter the state? That would point to it being Jhana, and from your description, a particularly hard one.

As for the energy explosion, I can't really say, but as for the strikingness of the state, it sounds like something I experienced once, including the loss of concentration upon coming out of it. It was actually my first post on these forums, here is the link, with the really relevant part being the responses by Dauphin Supple Chirp (who captured the experience much better than I did) and Not Tao's responses to him, 2/3 of the way down the page:

http://www.dharmaoverground.org/web/guest/discussion/-/message_boards/message/5614317

Best of luck,
Kyle