However, daydreaming may not be as harmless as it seems: According to a study published Thursday in the journal Science, a wandering mind is often an unhappy one.
Using an iPhone application that prompts users to answer survey questions about their mental state throughout the day, researchers at Harvard University tracked how frequently the minds of 2,250 U.S. adults wandered and how their moods changed accordingly.
Based on self-reported mind-wandering and self-gauged levels of happiness collected via subjects' phones, researchers found that people reported being significantly less happy when their minds wandered than when they were focused on the task at hand.
"The human capacity that underlies our ability to mind wander is incredibly important," says Matthew Killingsworth, the lead researcher and a doctoral candidate in psychology at Harvard University. "It allows us to plan for the future, process the past, imagine things that could never occur, but at the same time, the data shows that when people use this capacity it reduces their happiness."
Daydreaming was a surprisingly frequent practice -- subjects reported meandering thoughts nearly half of the time they were questioned -- but this state was consistently associated with a lower mood, even when subjects were thinking about pleasant things, researchers found.
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