Publication: New Scientist
Published: January 12th, 2008
By: Graham Lawton
I’M CONCENTRATING hard, staring at a small white square in the middle of my computer screen. Any second now a letter is going to flash up inside the box. At the same time a bird will pop up elsewhere on the screen. My task is to hit the bird with my mouse, then type the letter in the box.
I’m playing a game called Birdwatching, and if my boss catches me at it I’ll have some explaining to do. But I’ve got an excuse: I’m training my brain. The more I practise, the better I’ll get and the more powerful my brain will become – or at least that’s what I’m told.
Birdwatching is the brainchild of San Francisco-based Lumos Labs, just one of the dozens of companies that have sprung up in recent months to cash in on the “brain-training” craze. Like most of its competitors, the theory behind its sales pitch is straightforward. Your brain is like a muscle: the more you use it, the stronger it will get.
For those who believe that claim, there are dozens if not hundreds of brain-boosting games now on the market, not to mention a plethora of books and magazines on the same subject. The best-known product is a video game called Dr Kawashima’s Brain Age, developed by neuroscientist Ryuta Kawashima from Tohoku University in Japan; it is marketed in the UK and Australia as Brain Training: How Old Is Your Brain? and endorsed by actress Nicole Kidman.
While each brain trainer makes slightly different claims, broadly speaking they offer one of two benefits. Either they will “enhance normal brain functioning” – things like attention, memory and processing speed – or they will “slow down the inevitable decline that comes with age”. Practically all of the companies say that their programs are based on the latest scientific evidence.
So is it worth investing in brain training, and do you risk being outsmarted if you don’t? Unfortunately for the wannabe genius, there are no simple answers. While there is no shortage of studies suggesting that some cognitive functions can be trained, the link between most of these programs and a better-performing brain is still unproven. “Does brain training work? It depends,” says Torkel Klingberg, a brain-training expert at the Karolinska Institute in Stockholm, Sweden. “That’s like asking, ‘Do drugs work?’. It depends on the molecule.”
Commercial brain training has been around for at least a decade, but has only really caught on in the past couple of years. According to figures published in The New York Times in November 2007, the US brain-training market was worth just $2 million in 2005 but was expected to be worth $80 million in 2007. The catalyst for this exponential increase was probably the release of Brain Age in 2005. The game runs on the Nintendo DS console and has sold more than 14 million copies worldwide. For an investment of around $20 (plus the price of the console) and a few minutes’ concentration a day, it promises to help you “get the most out of your prefrontal cortex”. Like its competitors, Brain Age is a collection of puzzles and video games that use cognitive skills such as memory, attention and rapid processing. As with all video games, the more you play, the better you get. What makes brain-training games special, so the story goes, is that your improvements are not just within the context of the game but manifest themselves in the real world as well.
On the face of it, this makes a lot of sense. It’s well known that older people who stay mentally active are more resistant to cognitive decline and dementia, and many scientific studies have backed up this “use it or lose it”
hypothesis (New Scientist, 17 December 2005, p 32). So if it works for older people, shouldn’t it work for everybody?
Perhaps it does. Over the past 15 years or so, neuroscientists have gathered abundant evidence that important cognitive functions such as memory, attention and processing speed can be improved by training, not just in older people but in young, healthy adults too. There are also numerous studies showing that challenging a specific part of the brain encourages that region to grow and develop, as in the well-publicized example of the London taxi drivers, who develop a larger hippocampus – the part of the brain responsible for spatial memory – as they learn their way around the city (Proceedings of the National Academy of Sciences, vol 97, p 4398).
Most companies offering brain training stop short of specifying how their product will physically change your brain. For evidence that brain-training programs work, they tend to point to the sheer weight of accumulated data, but dig below the surface and things start to look far from clear cut.
“There’s 12 to 15 years of good laboratory science that we can direct brains in a corrective direction,” says Mike Merzenich, a neuroscientist at the University of California, San Francisco, who also runs a company called Posit Science, which develops “brain-fitness” programs. “Just about anything can be improved. The brain is massively plastic – if engaged in the right way.”
It’s a key distinction: the brain certainly appears to be trainable – but you have to train it in the right way. “There’s lots of confusion in the field,” says Klingberg. “People say ‘use it or lose it’, but that doesn’t mean anything unless you define ‘use’ and ‘it’.”
That means that each brain-training program needs to be evaluated on its own merits. And when you do that, doubts begin to emerge. Experiments on specific programs tend to be small and poorly controlled. Unless a training program has been shown to succeed under the stringent conditions of a proper clinical trial, the results must be treated as provisional, says Merzenich. By the same token, companies’ claims need to be appraised with caution. “It’s an incredibly murky area,” says Merzenich.
“There are good studies but not many controlled trials. There’s a massive level of underlying science but not much has been reduced to hard, gold-standard levels.”
Lumosity, created by Lumos Labs, is a typical example. According to Mike Scanlon, chief scientist at the company, the brain-training program was adapted from experiments in psychology and cognitive neuroscience literature. The company’s own trials show that 30 training sessions produced significant improvements on a battery of standard tests of visual attention and working memory. This sounds impressive until you take into account the trials only involved 14 people, plus eight controls who received no contact, and that the results have not been published in a peer-reviewed journal. Lumos claims that its program trains processing speed and cognitive control, but it has yet to present evidence to back this up.
This is not to say that Lumosity doesn’t work or that the trials were badly designed. There’s no doubt the games are fun and that you get better at them with practice. What it does suggest is that Lumosity cannot claim to be a proven route to a better brain, and that the company’s results, and those of many of its competitors, need to be understood for what they are – provisional.
This situation is unlikely to change, particularly as there is no incentive for companies selling brain training to conduct proper trials. As Merzenich points out, it can cost $2 million to run a controlled trial, and few companies are willing or able to shell out that kind of money. “I want to continue the research,” says Scanlon, “but we’re not going to keep on blowing out studies on more and more people.” In any case, the brain-training market is not regulated by an FDA-like body that demands scientific proof of a product’s efficacy before allowing it to be sold. Nor does a lack of clinical data seem to be a barrier to commercial success, if the growth of the US market is anything to go by.
Despite a lack of large trials, Lumosity has at least been shown to make generalisable improvements: trainees not only get better at the training program itself, they also improve on independent tests of working memory and visual attention. This, says Merzenich, is one of the minimum requirements for a credible brain-training program. “It’s crucial, or you’re making it up,” he says. Not all companies show such evidence of generalisability, however. Notable among these is Nintendo, though the company is careful not to claim that Brain Age is scientifically validated, merely stating that it is an entertainment product “inspired” by Kawashima’s work.
The absence of cast-iron evidence isn’t necessarily seen as a problem, however. Susan Greenfield of the University of Oxford has publicly endorsed MindFit, a brain-training program for older people, on the back of research that has yet to appear in a peer-reviewed journal. She says she has seen enough evidence to convince her that brain training is worth the effort. “I believe it works,” she says. ”What is there to lose? There’s no risk, and every chance it might be doing something.”
Looked at in this way, brain training is rather like an anti-ageing cream: if people want to spend their money on something that won’t do them any harm and might do them some good, who’s to stop them? Also like anti-ageing cream, brain-training companies are not as up front as they might be when it comes to potential limitations. Klingberg says that consumers should be more questioning. “I’m surprised that people don’t care more about the science,” he says, “that they don’t ask, ‘where’s the evidence that this works?’.”
Against this confusing background of sales pitches and celebrity endorsement, is there any decent, independent evidence that brain training can work? Encouragingly, there is. There may not be many large-scale clinical trials, but those that have taken place all point in the same direction.
In 2006, a group led by Karlene Ball of the University of Alabama, Birmingham, published the results of a huge US government-funded study of the “use it or lose it” hypothesis. Between 1998 and 2004, they put a total of 1884 healthy older adults through an intensive six-week programme designed to train either their memory, reasoning powers or processing speed.
When the volunteers were tested post-training, Ball’s team found the programme had not only worked but the improvements were generalisable: those given memory training did significantly better on other memory tasks, and so on. Remarkably, when participants were re-tested five years later the effects were still detectable, even with no further training (Journal of the American Medical Association, vol 296, p 2805). On the downside there was no evidence that the training had any effect on real-world activities. Even so, some of the team are now converting the results into practical brain-training programs for the elderly, says lead author Sherry Willis of Pennsylvania State University, State College.
Other trials have done even better. Merzenich and colleagues at Posit Science published the results of another big trial in 2006. They tested Posit’s “Brain Fitness Program” – commercially available for $395 – on 182 older adults. Those who received the real thing – the rest were either given placebo training (watching a DVD) or no contact – scored significantly better on memory tests, and the improvement was still there three months later (Proceedings of the National Academy of Sciences, vol 103, p12523).
Late last year Posit released preliminary results of another trial. With 524 participants aged 65 or over, it is the largest trial yet of a commercially available brain-training program. Judging from the available information – the results were presented as a poster at a conference – the outcome was good. Brain training significantly improved processing speed and memory, and three-quarters of participants said they noticed improvements in their day-to-day lives. “There’s a very large effect,” says Merzenich. The memory results alone were the equivalent of being 11.2 years younger, he says.
Klingberg, however, sounds a note of caution. He points out that Posit expresses its memory results in terms of “effect size” – a measure of statistical significance. “An effect size of 0.2 is weak, 0.5 moderate and 0.8 is strong,” he says. Yet Posit reported an effect size of just 0.25 in the smaller trial and 0.28 in the larger one. Reassuringly, Klingberg says he has solid evidence that working memory can be trained and that the effect persists for at least three months (Journal of the American Academy of Child and Adolescent Psychiatry, vol 44, p 177). All things considered, it’s hard not to conclude that brain training has been proven to work – under certain circumstances.
It is also worth pointing out that no study has shown that brain training makes cognitive abilities any worse. At the very least, it’s a fun way to while away a train journey or rainy day. Just don’t expect to develop a photographic memory or lightning reactions overnight – or in fact, at all. “The analogy I use is giving up smoking and taking up jogging,” says Greenfield. “It might reduce the risk of cancer. But it’s not a guarantee.”
The Human Brain – With one hundred billion nerve cells, the complexity is mind-boggling. Learn more in our cutting edge special report.
A miracle cure?
Brain training may or may not turn intellectual zeros into heroes, but for psychiatric illnesses such as schizophrenia, depression and obsessive-compulsive disorder (OCD), it seems to be a miracle cure.
The most advanced research in this area has been done on schizophrenia by Posit Science. For the past three years, Mike Merzenich, a neuroscientist at the University of California, San Francisco, who also runs Posit Science, has been running two trials of intensive brain training. The trials are ongoing, but Merzenich says the results to date are very encouraging. One of the key deficits in schizophrenia is severe disturbances of memory, attention and executive functions. Brain training can restore these to near-normal levels, says Merzenich. “No drug can do that.”
Merzenich also says he has had promising early successes with depression, OCD and with stopping people showing early signs of schizophrenia from progressing to the full-blown disease. ”This is a superior strategy to manipulating the brain’s biochemistry with drugs,” he says. “Instead, you direct the brain to sort itself out. This is speculation, but I think neurological and psychiatric illness will eventually be directed towards brain correction.”
This, perhaps, is where brain training will have its greatest impact – not as a brain gym, but as a treatment for people with serious mental health problems or brain injury. Torkel Klingberg, a brain-training expert at the Karolinska Institute in Stockholm, Sweden, also sees the power of using brain training as therapy. His company, CogMed, sells a computer-based training program for children with attention-deficit hyperactivity disorder and other attention problems, and he says there is much promise in the approach – but also a long way to go. “Brain training is where internal medicine was in the 19th century,” he says. “We need to find the specific conditions under which it works.”
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