Scientists have long believed that the brain's "default network" - that part of the brain associated with routine mental activity - was the only area associated with activity during the state of daydreaming. However, a study conducted by the University of British Columbia finds that wandering minds are more active - and productive - than previously thought.

To conduct the study, University of British Columbia investigators placed participants inside an fMRI brain scanner. Each individual was asked to perform a routine task, for example, pushing a button when numbers appeared on the screen. Moment-by-moment attentiveness was tracked through brain scans, through subjective reports provided by participants and by tracking how well they completed the simple task. The researchers learned that the brain's "executive network," which includes the lateral prefrontal cortex and the dorsal anterior cingulated cortex - regions within the brain associated with complex problem-solving - becomes highly active during daydreaming episodes. And such episodes occupy up to one third of our waking lives. Moreover, the less subjects were aware that their mind was wandering, the more both networks were activated. The findings suggest that the act of daydreaming is actually an important cognitive state in which humans may unconsciously turn their attention from the immediate task at hand to solving more critical issues.

"Mind wandering is typically associated with negative things like laziness or inattentiveness," says lead author, Prof. Kalina Christoff, UBC Dept. of Psychology. "But this study shows our brains are very active when we daydream - much more active than when we focus on routine tasks. "This is a surprising finding, that these two brain networks are activated in parallel. Until now, scientists have thought they operated on an either-or basis - when one was activated, the other was thought to be dormant." Study findings were published in the Proceedings of the National Academy of Sciences.

News Release: Brain's problem-solving function at work when we daydream    www.eurekalert.org   May 11, 2009