Source | World Economic Forum
You’ve probably heard of “brain training exercises” – puzzles, tasks and drills which claim to keep you mentally agile. Maybe, especially if you’re an older person, you’ve even bought the book, or the app, in the hope of staving off mental decline. The idea of brain training has widespread currency, but is that due to science, or empty marketing?
Now a major new review, published in Psychology in the Public Interest, sets out to systematically examine the evidence for brain training. The results should give you pause before spending any of your time and money on brain training, but they also highlight what happens when research and commerce become entangled.
The review team, led by Dan Simons of the University of Illinois, set out to inspect all the literature which brain training companies cited in their promotional material – in effect, taking them at their word, with the rationale that the best evidence in support of brain training exercises would be that cited by the companies promoting them.
But the CEO says it works …
A major finding of the review is the poverty of the supporting evidence for these supposedly scientific exercises. Simons’ team found that half of the brain training companies that promoted their products as being scientifically validated didn’t cite any peer-reviewed journal articles, relying instead on things like testimonials from scientists (including the company founders). Of the companies which did cite evidence for brain training, many cited general research on neuroplasticity, but nothing directly relevant to the effectiveness of what they promote.
The key issue for claims around brain training is that practising these exercises will help you in general, or on unrelated tasks. Nobody doubts that practising a crossword will help you get better at crosswords, but will it improve your memory, your IQ or your ability to skim-read email? Such effects are called transfer effects, and so-called “far transfer” (transfer to a very different task than that trained) is the ultimate goal of brain training studies. What we know about transfer effect is reviewed in Simons’ paper.
As well as trawling the company websites, the reviewers inspected a list provided by an industry group Cognitive Training Data of some 132 scientific papers claiming to support the efficacy of brain training. Of these, 106 reported new data (rather than being reviews themselves). Of those 106, 71 used a proper control group, so that the effects of the brain training could be isolated. Of those 71, only 49 had a so-called “active control” group, in which the control participants actually did something rather than being ignored by the the researchers. (An active control is important if you want to distinguish the benefit of your treatment from the benefits of expectation or responding to researchers’ attentions.) Of these 49, about half of the results came from just six studies.
Overall, the reviewers conclude, no study which is cited in support of brain training products meets the gold standard for best research practises, and few even approached the standard of a good randomised control trial (although note their cut off for considering papers missed this paper from late last year which showed the benefits of online brain training exercises, including improvements in everyday tasks, such as shopping, cooking and managing home finances.