One of the most severe and tragic cases is that of Clive Wearing, an English musicologist whose brain was destroyed by a rare complication of the herpes virus to the point where he had not only forgotten most of his past, but could not hold a current memory for more than a few seconds, literally a half-minute at most. I watched a documentary about him and his amazingly patient and articulate wife, which was uploaded (in ten-minute segments) to YouTube; Part 1 here. I'm watching them again with Ziggy now.
Stories like this really make me think about human mortality; how fragile we are, how all of our life's memories can be destroyed, how our very existence seems to hang by a thin, frayed thread. I keep hoping to have my own "awakening", to bring back the creative energy I once had as a teenager, to produce the books and songs and pictures inside me, to leave some kind of evidence or trace of my existence before I meet my own demise, untimely or not. I simply cannot continue to take my life and good health for granted.