[Balladeer]

The book "Stolen Focus" had an interesting point on this effect that resonated with me. While mind wandering -- letting your mind explore the past and future -- can be a gift and creative boon, it can only do so in a low-stress environment. People often rate "mind wandering" as one of the least pleasant daily activities, even below chores, because, mind-wandering in a high stress environment leads to rumination, and "ruminating on negative emotions becomes torment."