Testing for creativity, and its corresponding physical attributes in the brain, requires defining the term, but creativity is not so easily broken down. "'Creativity is kind of like pornography — you know it when you see it,' said Rex Jung, a research scientist at the Mind Research Network in Albuquerque...Like many researchers over the past 30 years or so, Dr. Jung has relied on a common definition of creativity: the ability to combine novelty and usefulness in a particular social context. As the study of creativity has expanded to include brain neurology, however, some scientists question whether this standard definition and the tests for it still make sense."