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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Fastness of recognition: The faster we recognise something (heuristically) the more attractive we judge it to be and if the image match prototypes the faster the processing.

How this translates to user interface design? Simple. When you design a UI pay close attention to your maket segment and demographics. Try to find out what your users are using on a daily basis and have a close look to your most successful competitors. Try to mimic them without being a clone and you’ll have instant satisfaction.