The findings suggest that people stymied by a creative task would do well to take a break and have some fun, Anderson suggested, because getting annoyed and anxious will only make it more difficult to think "outside the box," as it were. "Stop working on it, do something you enjoy, and come back to it."

While people under threat are known to zoom in sharply on small details -- a kind of tunnel vision known as "weapon focus" -- the effect of positive mood on attention is less clear, Anderson and his team note. They theorized that people who were feeling good would have a more expansive, less selective focus.

To investigate, they had 24 university students perform two tests of attention. Positive moods were induced by playing Bach's Brandenberg Concerto No. 3 and negative moods by a Prokofiev piece played at half speed. To produce a neutral mood, participants read a series of facts and figures about Canada.

When they were in a positive mood, participants scored higher on a "remote associates" task -- a measure of creative thinking in which they were asked to identify a word that linked three apparently unrelated words.

To test selective attention, participants were told to look for one of two letters in their central vision, while other letters were projected in the periphery. The degree to which the peripheral letters slowed their response was used to gauge the strength of their focus. While in a good mood, the researchers found, the study participants noticed the letters flashed in their peripheral vision, while they were able to ignore these letters when they were in negative or neutral moods.

When feeling happy, Anderson explained, "your attentional window is actually bigger -- it's like looking through a big window versus a small window."

A neutral or negative mood is a good state of mind for working on accounting spreadsheets, where focus, not creativity, is key, he added. Conversely, for tasks requiring a broader view, Anderson said, a good mood will definitely be an asset.

He and his colleagues conclude: "Donning the proverbial rose-colored glasses of positive mood then may be less about the color and more the expansiveness of the view."

SOURCE: Proceedings of the National Academy of Sciences, online December 18, 2006.

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