I believe that we incarnate over and over again. I say this because sometimes in meditation I have experienced flashbacks where I am living different lives. It is like they are running concurrent to this life. It happens near the surface of meditation, of course, not when I’m deep into it.
If I wanted to, I could go into one of the other lives at any time, but I don’t bother any more because I have learned what I needed to from the experiences and so I concentrate on this life now.