The US localization of Brain Age: Concentration Training for 3DS is now due out on February 10, 2013, pushed back from the original release date of December 3, 2012.
Brain Age: Concentration Training has players perform mental gymnastics designed to improve "working memory." Some tasks have players answer problems on a delay, forcing them to wait and see the next problem before writing the solution to the previous one. It's like a backflip for your amygdala.