Medical experts call the Alzheimer's phenomenon of end-day confusion and restlessness "sundowning," a period of increased uncertainty, agitation and drifting in a fog as light fades to black, a time of greater rage and mood swings in the shadows of the mind. Greg O'Brien, knows this phenomenon all too well, as he walks through the confusing and life-altering world of living with Alzheimer's Disease. O'Brien writes about the darkness he and so many others walk through here.