http://www.wired.com/imageviewer?imagePath=/images/article/full/2008/04/smart_software_500px.jpg&imageCaption=Scientists%20used%20a%20modified%20version%20of%20the%20n-back%20test,%20which%20is%20schematized%20above,%20to%20achieve%20gains%20in%20fluid%20

Scientists used a modified version of the n-back test, which is schematized above, to achieve gains in fluid intelligence previously thought impossible. The image shows how users were forced to remember both visual and auditory information streams.

Forget Brain Age: Researchers Develop Software That Makes You Smarter