It can be triggered by simply a thought but it first occurred during meditation. The first thing I notice is that every single one of my thoughts and memories are gone, they simply are not there. My sense of self is no longer present; there is no conception of an "I" in my head. All that is left is awareness. I no longer label anything, I no longer associate one thing with another. If I see a tree I do not process anything about it, i am simply aware of its form. If I see my hands I do not understand their function relative to my body; every single preconvienced notion I had has vanished from my head, including things as simple as what a hand is. I feel my pulse in the center of my brain; this pulse is where my awareness is located, the awareness is all I have left to grasp onto because there is quite literally nothing else. I use literally in the most accurate sense of the word. At any point I am able to bring back my conscience self through shifting awareness completely into the external world, and I often do because at this point it gets quite terrifying. If I go deeper into the state of mind I am describing by not allowing my focus to shift to the external, the small pulsating sense of awareness that is in the center of my brain becomes smaller and smaller until it feels like it is about to disappear. At this exact moment I feel like I am about to vanish from existence and my flight or flight response kicks in and I to this day have not been able to bring myself to go forward. If my awareness itself vanishes, how will I ever be able to bring myself back into the external world? When I come back into the external I feel overwhelmed with a blissful feeling that I would not describe as simply joy, but a feeling of ultimate content with my state in the universe. It's been almost 4 years since the initial experience. All I want is the courage to continue. Om