How, then, would we go about repair of ischemic brain? One point Robert Ettinger made 20 years ago still stands, and is quite profound. In The Prospect Of Immortality , Bob made the comment that brain cells after ischemia (or freezing) simply are not universally destroyed. Even in adult human beings, significant areas of brain can survive lengthy periods of ischemia. What does that mean? Bob described a column of soldiers after a machine gun attack. If none of the soldiers ever gets up or shows any sign of life, then they've probably all been killed. But if only a few get up afterward, then many more are probably wounded but still alive.