Try this and tell me if it works for you, please.
Begin your mind map during your preview, instead of using linear note-taking. Begin your "branches" as a basic outline and superficial representation of the book, somehow incorporating your trigger words.
After you PR a book, begin adding branches after each Activation pass through the material, adding more detail with each session. Sort of a "building towards comprehension" type of theme.
Once again, please let me know if it works for you.