I believe there are two parts of us that leave this earthly body when we die, and there isn't any physical part that clings to the body after death. The two parts are the soul, with the memories of all of our past lives, and is what will enter our next incarnation, and our spirit, the essence of what we were in this life. Until the time nears when the soul incarnates again, the spirit is what is felt, seen, connected to us after a loved one's death, when it returns to the soul. So based on that belief, I have no fear that anything that is done with my body after its death is going to have any effect on my soul, or on my future lives. We all have our beliefs, and that's what directs our decisions, and that's how it should be.