Some very clever people with better things to do than fiddle about on a Nintendo DS have explained to the rest of us that brain training games are useless.
A study from the UK Medical Research Councilís Cognition and Brain Sciences Unit (CBSU) debunks claims that playing these games can improve your mental agility.
"Brain training, or the quest to improve brain function through regular use of computer tests, is a multimillion pound industry, yet up until now there's been a real lack of robust evidence to show it really works," says the CBSU's Dr Adrian Owen.
"Our findings will no doubt surprise millions of people worldwide who do some form of brain training every day in the belief that 'exercising' their brain makes them better at everyday thinking tasks."
The study compared two groups using training games with one that simply used the internet to answer general knowledge questions. It found that all three groups improved by a similar amount - and that wasn't much.
"In one of our computer games that tests memory by assessing how many numbers could be remembered by players, we found it would take almost four years of playing brain training games regularly each week to remember just one extra digit!" says Owen.
The team plans to continue the experiment with those subjects aged 60 or over to investigate whether brain training does, as has been claimed, protect against Alzheimer's disease.
Previous trials, such as a 2005 study of Nintendo's brain training package and a 2006 investigation of similar games, found significant improvements. However no previous study has been on this scale.