Experiencing nothing at death

What does it mean to experience nothing at death? What does it mean to experience nothing when under the influence of anesthesia? These two situations might suggest that you are nothing but the functioning of your current brain. If as superimmortality predicts that you can be experiencing other consciousness at the same time produced by different bodies would you not experience these other consciousnesses when you are not experiencing any consciousness with your current body. Does the fact that you do not experience these other consciousness prove that superimmortality is wrong?

According to superimmortality what would it take for you to have evidence of this continuation of consciousness in another body and then come back alive again in your current body and have memories of these other experiences of a different life? There would have to be changes in your current brain so that when it functions again consciously it will produce memories of these different experiences that occurred in another body. According to superimmortality there could be more than one body producing a consciousness that you would experience so why would you just experience the consciousness produced by one? To have a memory of experiencing nothing while under the influence of anesthesia there has to be some functioning of the brain that when awake again is aware of this period of time where you were not aware. We take cues from the clock being at a different setting and things changing around us. One moment you are wheeled down a hall to the operating room and the next moment to you are waking up in a recover room. You weren't in pain, now you are. It was eight in the morning, now it is two in the afternoon.