Those TED talks are always fun to watch. A friend sent me this one from Manoush Zomorodi, who has explored what happens to people if they let themselves be bored. Or the opposite: what happens when we can't stand being idle for even a second.
The bulk of the discussion has to do with digital distraction and a project that Zomorodi tried to get people using their mobile devices less with the goal of opening up horizons for them to think about other things. Or even be "bored." And the claim is that this boredom opens the door for us to make mental connections that we don't make when we are engaged in an activity.
The short form of this is something people have been saying for a long time. Every time we switch attention, it causes us to burn mental energy. And that energy lost ends up costing us: I usually focus on the fact that everything takes longer when my focus shifts. But we also lose creativity, sleep, energy...