Probe every 2-4 minutes

Hello Everyone,

What I would like to do is display whole pages of text from a book, and while reading, have the participants press a button when they catch themselves in 'task unrelated thought'. In addition, I would like to present a probe every 2-4 minutes asking them to indicate by button press if they are engaged in task unrelated thought, or are focused on the reading at the time of the probe; and I want to make sure they aren't prompted right after a self-report of mind-wandering. I would appreciate any help on this, thanks!