the less time it took participants to classify a pattern, the more attractive they judged it.

The phrase "easy on the eyes" may hit closer to the mark than we suspected.

Experiments led by Piotr Winkielman, of the University of California, San Diego, and published in the current issue of Psychological Science, suggest that judgments of attractiveness depend on mental processing ease, or being "easy on the mind."

"What you like is a function of what your mind has been trained on," Winkielman said. "A stimulus becomes attractive if it falls into the average of what you've seen and is therefore simple for your brain to process. In our experiments, we show that we can make an arbitrary pattern likeable just by preparing the mind to recognize it quickly."

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Working with random-dot and geometric patterns -- in an attempt to "use stimuli that were free of reproductive content," Winkielman says, and would "get at a general principle of cognition" -- Winkielman and his colleagues first "prepared" participants' brains to perceive a prototype and then asked them to categorize different degrees of variations around that same prototype and rate their appeal.

"As predicted," the researchers write, "participants categorized patterns more quickly and judged them as more attractive when the patterns were closer to their respective prototypes."

And: "Critically, the less time it took participants to classify a pattern, the more attractive they judged it."

Even more significant, Winkielman said, is that when processing ease was controlled -- when, that is, the categorization speed was factored out of the equation -- much of the relationship between closeness to prototype and attractiveness disappeared.

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