Since its launch in 2005, Nintendo's Dr Kawashima's Brain Training has sparked a market phenomenon. According to Nintendo the title, along with its sequel More Brain Training from Dr Kawashima, has sold over 30 million units worldwide, accounting for one in every five DS games purchased.
Such is the success of the Brain Training (or Brain Age in Japan/US) titles, they have become almost synonymous with the company's successful strategy to harness the spending power of casual gamers. With the help of Nicole Kidman and Patrick Stewart, Brain Training has vaulted the DS into new demographics, bringing consoles to the hands of people who would have once eschewed anything containing so much as a microchip.
Wii Fit also caters for this self-improvement market and has met with equally spectacular sales. But while few would question the benefits of games encouraging physical activity, the merits of brain training are not so clear-cut - here, in the second of our two-part series on games and health, Alastair McQueen puzzles over the research.
Enjoyment and Fun
Most doctors agree that keeping active, being social and enjoying hobbies is good for your brain as you age. Professor Snyder, a clinical neuropsychologist and professor of neurology at The Warren Alpert Medical School of Brown University in Rhode Island, USA, has been involved in ageing and dementia research for over 20 years.
"The issue for me isn't whether or not staying mentally active is healthy for you. I think everyone would agree that that's the case," he says. "To me the issue is - is there any added benefit over and above that normal, good, sound clinical advice for the use of games or devices?"
Having recently conducted the most comprehensive review of the evidence behind 'cognitive interventions' in healthy elderly people to date, Professor Snyder isn't convinced.
"There's just no credible evidence I can find that actually shows that behavioural intervention, over and above normal appropriate advice about healthy activities of daily living, confers any added benefit," he says.
A recent report by Which? backs this view. The consumer group asked three experts to look at the research behind several cognitive intervention products. They found the evidence "weak", claiming that crossword puzzles might be just as effective.
Many of the studies Professor Snyder identified lacked appropriate control groups (people in the study who are given an equivalent activity, or none at all) for the results to be compared to. But the lack of quality evidence doesn't necessarily mean the interventions don't help - just that they haven't been shown to. Carrying out trials in people is complicated, and finding the right study design isn't easy.
"Humans are messy creatures and there are all sorts of intervening or unintended variables that can creep in and cloud the data," Professor Snyder explains. "So I think, to be fair, the research on this topic is a bit messy partly because the endpoints themselves are difficult to really nail down."
Indeed, there is some uncertainty over what brain training games hope to achieve. Some, like Dr Kawashima's Brain Training, give you a 'brain age' score. However, Nintendo says these should not necessarily be taken as medically accurate.
Rob Saunders, Senior UK PR manager for Nintendo UK explained: "Nintendo does not make any claims that Brain Training is scientifically proven to improve cognitive function.
"We claim that the Brain Training series of games, like filling in a crossword or playing Sudoku, are enjoyable and fun. These mental exercises can also help to keep the brain sharp, just like other similar activities, and this is a fantastic bonus."
But the market isn't all Nintendo's. Dozens of companies have sprung up, selling cognitive intervention software or subscriptions allowing users to log in, train their brain, and track their progress online. Some claim to offer improvements to cognitive abilities at any age.
Dr Elkhonon Goldberg is a clinical professor of neurology at New York University School of Medicine. He thinks that most of the products on offer are based on the same design principles.
"In order to successfully target a younger audience the claim that they make is 'smarter'. But when they target an older audience the claim is that they'll slow down brain ageing. The surface features of these exercises would be different depending on which audience you target, but they would be fundamentally the same," he explained.
Nevertheless Dr Goldberg feels that cognitive intervention software can play a role in moderately improving aspects of cognitive function. "They have measurable impact," he said.
"In other words you can document the effect with various tests which quantify your performance in artificial testing situations. How much of an impact they have on real life performance is harder to capture and that is pretty much in the eye of the beholder."
So What Makes a Good Brain Game?
"I would say that the exercises should be diverse and cover a wide range of cognitive functions and so this is the foremost requirement. They should also be challenging but not humiliating," said Dr Goldberg. "And they should be captivating. The pill should never be bitter. A sweet pill is more likely to be consumed than a bitter pill."
But improvements in test scores don't necessarily mean slowing down brain ageing or making you smarter, cautions Professor Snyder.
"Many of these products are teaching people how to solve particular puzzles, use new strategies, figure out hidden paths or what have you, and that's fine if they're enjoying it, that's great. If they learn something from it that's terrific too," he explained.
"But humans who are otherwise reasonably healthy get better at anything that they continue to practise, and these practice effects can look like you're actually reversing the signs of ageing."
Although brain training games are often equated to crosswords or Sudoku, Dr Goldberg feels they can offer more than their paper-based cousins. "There's a transition from paper and pencil culture to a software-based culture. And I think that software is much more versatile. You can do more, it's a much richer medium," he explained.
But can cognitive intervention software use the medium to get real results? A recent study by researchers at the University of Michigan suggests that maybe they can. A scientist there tested a tool that asks people to remember the shifting location of shapes and a sequence of spoken letters at the same time.
Volunteers who used the software over nineteen weeks demonstrated improved 'fluid intelligence' - or general problem solving ability - in separate tests. While it only involved 35 volunteers, this is one of few studies to demonstrate a transferable effect from one cognitive task to another. And a tool like this would be impossible on paper.
"It might be the case that the presentation of tasks via computer might allow for multiple routes of encoding and processing of information," commented Professor Snyder. "This might confer benefits in 'exercising' and further developing fluid reasoning skills."
"But as of this moment, there isn't a large amount of convincing data to support this as a clinically-relevant bonus in the elderly - just a very tiny handful of suggestive studies."
All Aboard the Brain Train
So while evidence that brain training games can really slow down brain ageing might not yet be apparent, the industry seems certain to grow. In the US alone the consumer market is estimated to have jumped from a few million dollars in 2005 to USD 80 million in 2008. But why now?
"As we age we notice mild changes in our memory, word finding abilities and name recognition which are normal and expected. For most of us who are used to not having any such changes at all, even if they're slight it's something that's very bothersome," Professor Snyder explained.
"We have an ageing population that's living longer, that's very interested in maintaining quality of life, and who would do whatever it can to protect that," he said, adding that the compelling nature of brain training games only adds to their success.
"It looks like it should work. It feels like it should work. And so the market is, I think, just going to grow and grow."
Written by Alastair McQueen. Part one in the series, an editorial by Dr Matthew Capehorn on obesity in children, is also available.