The New York Times reports that remembering may be like reliving, from the perspective of the neurons doing the remembering. Remembering neurons appear to behave like they did when first experiencing whatever is being remembered.
I wonder, if our brains could quickly store more information in a readily accessible manner, and if our eyes and ears (and the remainder of our body) could reproduce their states from that stored information, perhaps remembering would be no different than reliving for the entire organism? To remember is to simulate the past. At radical degrees, to remember is to recreate the past.
In the distant future, perhaps a neohuman (or posthuman) remembering our world would, through the act of remembering, reproduce our world. As I've mentioned before, there seems to be little reason to distinguish between a neohuman and a universe.