So glad to have a name for this experience! I was driving in a place that is completely familiar. All of a sudden I didn't know who I was or where I was or what anything was. I didn't know anything. I was so disassociated from everything. It's not the same as blanking out as when doing a familiar drive and not remembering the journey. It is much more intense and all-encompassing.
I did know that if I just kept going I would come back. It was only for a short period, a minute at the most. It only happened once and I think it had to do with anxiety. I can't imagine how difficult it would be to experience this more than once. The thought still freaks me out and it was years ago.