They report on 11 experiments. In most, they asked participants to put away any distractions and entertain themselves with their own thoughts for 6 to 15 minutes. Over the first six studies, 58 percent of participants rated the difficulty at or above the midpoint on a scale (“somewhat”), and 42 percent rated their enjoyment below the midpoint. In the seventh study, participants completed the task at home, and 32 percent admitted to cheating by using their phones, listening to music, or doing anything but just sitting there. (In the lab studies, one participant’s data was tossed because an experimenter had accidentally left a pen behind and the subject used it to write a to-do list. Another’s was tossed because an instruction sheet had been left behind and he used it to practice origami.)
Participants rated the task of entertaining themselves with their own thoughts as far less enjoyable and more conducive to mind-wandering than other mellow activities such as reading magazines or doing crossword puzzles.