...University of Michigan psychologist John Jonides presented new findings showing that practicing this kind of task for about 20 minutes each day for 20 days significantly improves performance on a standard test of fluid intelligence—the ability to reason and solve new problems, which is a crucial element of general intelligence. And this improvement lasted for up to three months.There is an open source training program that I haven't yet tried. It is hosted on SourceForge.
Jonides, who is the Daniel J. Weintraub Collegiate Professor of Psychology and Neuroscience, collaborated with colleagues at U-M, the University of Bern and the University of Tapei on a series of studies with more than 200 young adults and children, demonstrating the effects of various kinds of n-back mental training exercises. The research was supported by the National Science Foundation and by the Office of Naval Research.
According to Jonides, the n-back task taps into a crucial brain function known as working memory—the ability to maintain information in an active, easily retrieved state, especially under conditions of distraction or interference. Working memory goes beyond mere storage to include processing information.