For an all-natural brain boost, skip the pills and hit the colors.

In the latest and most authoritative study on color's cognitive effects, test subjects given attention-demanding tasks did best when primed with the color red. Asked to be creative, they responded best to blue.

"Color enhances performance," said study co-author Juliet Zhu, a University of British Columbia psychologist.

Previous research on red's effects on the brain have found that it attracts people to food and can enhance sexual arousal. But research on the color's cognitive effects have been mixed: Studies have linked red to cognitive impairment on IQ tests, telemarketing pitches and analytical problem-solving, but also to improvements on low-demand tasks and clerical work. The latest findings tip the balance toward the red-as-brain-booster results and fits with work that showed a link between the color and arousal of neurobiological awareness and vigilance.

"Think about red, and what comes to mind: stop lights, stop signs, danger, ambulances," said Zhu. "People want to avoid those things, and that's why they do better on detail-oriented tasks."

While earlier studies tended not to test creativity, Zhu's findings provide a plausible explanation for blue's apparent role.

"Blue is the color of the sky, the ocean, safety," she said. "When their environment is safe, people are more explorative."

Zhu's study, published Thursday in* Science*, started with tests designed to measure avoidance and attraction. Students vigilantly avoided red and were strongly attracted to blue.

Blue linked to higher scores on subsequent tests of creativity, and red with better performance on memory tests.

State University of New York at Albany psychologist Ronald Friedman, co-author of a study that found red-linked drops on IQtests, called the findings "quite remarkable." Stony Brook University psychologist Markus Meier, also a co-author on Friedman's study, called Zhu's study "a great paper," one that underscores the unappreciated importance of color.

"Colors are everywhere in our lives," said Meier. "We should use them more carefully in all settings."

To test alternative explanations for the findings, Zhu's team showed that neither red nor blue influenced mood. Test subjects also spent the same amount of time on their tasks, suggesting that neither color affected their motivation.

The colors appeared to enhance performance, but not to impair it.

Red- and white-primed students had similar creativity scores, while blue- and white-primed students were equal on attention tasks.

Asked about the implications, Zhu suggested that people engaged in creative tasks surround themselves with blue, and with red when trying to focus.

"In our university, some professors use different color sheets for different groups during exams," said Meier. "Using them in an unthinking way could produce bad results for some students, and good for others."

Zhu is now studying the effects of red on other types of tasks.

It's possible, given the other effects provoked by red — interest in food and sex — that it will have different effects in other contexts.

"The science has been focused on the cognitive domain," she said.

"But maybe in the physical domain, like sports, red can be associated with a different meanings, like power or enthusiasm. That's what we're doing now."

Citation: "Blue or Red? Exploring the Effect of Color on Cognitive Task Performances." By Ravi Mehta and Juliet Zhu. Science, Vol. 324, Issue 5915, Feb. 5, 2009.

Image: Red and blue color samples used in the tests / Science

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