Later this year Oxford University Press is publishing The Oxford Handbook of Spontaneous Thought, edited by Kieran Fox and Kalina Christoff. I have a chapter on the history of spontaneous thought– or really, an argument about the possibility of writing the history of something that seems completely ephemeral and unrecoverable, and a description of some works that could help guide such a history.
I’ve put the near-final draft up as a PDF on Google Drive.