That’s a fascinating question. I am not sure about animal research on dreaming, but Thomas Metzinger is an experimental philosopher (for want of a better term) who studies the basis of the concept of the self as a coherent entity, and his work includes extensive research on phenomena like lucid dreaming, phantom limbs, and out of body experiences. I’m not talking about anything paranormal - there’s conditions under which people’s experience of perception and self become separated from our ordinary experience of “my self is sitting behind my eyeballs.” He collaborates closely with experimental psychologists and neuroscientists, so between his work and references you might be able to see if there’s a correlation.