If you learn mathematics in school, but then proceed to become a lawyer, will you have any benefit from mathematics, for example in terms of abstract reasoning? Very little is know about the cognitive mechanisms behind such transfer of knowledge, and most psychological theories assume that very little transfer exists (Singley & Anderson, 1989, Thorndike & Woodworth, 1901). Nevertheless it is undisputable that many of our cognitive skills build upon each other, and have benefits beyond just the skill itself. Moreover, the new controversial industry of Brain Training games has emerged where spectacular improvements on various cognitive measures is promised, even though empirical evidence for such improvements is rather weak (Chein & Morrison, 2010, Jaeggi et al, 2008, Karbach & Kray, 2009, Owen et al., 2010).