Defining What We Know

Defining things from what we know, gained through experiences of our lives while we are living. What of our experiences of dying, how exactly are we to define things that we have no knowledge of. Death takes us into a black nothingness where we normally know nothing of what is happening to us. How then can you explain experiences that a person has had when they die and are brought back to life. Apparently there are experiences of dying that we also go through, remembering them very vividly. How do we account for these memories that we've had after dying, I'd like to know, because I remember.