Does brain-training work?
The verdict on games, crosswords and other ‘brain-boosting’ exercises.
The brain is like a dense conglomerate of muscles, each one dedicated to a particular task. Exercise any one of them and it will get stronger, but you need to exercise them all to improve your general cognitive ability. If you practise adding up figures all day, for instance, you will get very good at adding up figures, but if you never resort to estimation – a skill performed by an entirely different brain ‘muscle’ from arithmetic – you will be no better than anyone else at judging, say, the size of a crowd.
Brain-training has been dogged by the difficulty of developing exercises that improve functioning across the brain rather than in one small part. It’s now recognised that suites of exercises – those that package together visual search exercises with motor coordination challenges and word-retrieval games, for instance – can have broad benefits. However, if you have a healthy brain capable of a normal range of skills, the best exercise you can get is real life. Taking an active part in the community, enjoying art, listening to music, engaging politically and enjoying a rich social life – these are the best training of all.
Not all of us, however, have optimally healthy brains. Nor is it always possible to develop or practise the full range of cognitive skills. Brains degenerate physically with age, just like every other part of the body, and many people can’t live life to the full because they’re locked into repetitive work or cut off for some reason from intellectual stimulation.
When people get older, their neurons tend to be less excited by environmental stimuli. This is partly due to reduced hormones and neurotransmitters, but partly because fewer events are novel and stimulating. Our brains have ‘been there, done that’, and are not inclined to use too much energy doing it again. Just as brain activity primes the brain to activate in the same way again, subdued brain activity reduces future activity. So, whether you go for computer gaming, reading, listening to music or playing sport, the first thing brain exercise should do is get you excited.
The second thing it needs to do is to work as many cognitive muscles as possible. Crosswords are the famous go-to exercise because they involve several elements of cognition: memory, problem-solving, and spatial sensitivity (noticing how the words fit together). If you do crosswords too often, however, you may get so good at them that they no longer stretch you. The person who boasts that they complete a broadsheet cryptic puzzle every day may be doing less for their brain than someone who struggles to solve a single clue in a much simpler puzzle.
The same is true of Sudoku. The numbers game can be very challenging, especially for newcomers, but doing Sudoku every day merely makes you better at Sudoku – a skill that is quite difficult to find a use for elsewhere.
Should you take supplements?
A varied diet should provide all the brain-healthy nutrients you need, but could you benefit from taking more of them? Omega-3 – the fatty acids found in fish such as herrings, sardines and mackerel – is the supplement best known as a brain-booster. But the evidence for its effects is underwhelming. A 2012 review by the Cochrane organisation – widely acknowledged as an authority on health research – found no evidence that omega-3 reduces the risk of cognitive impairment, while a 2015 meta-analysis by Canadian scientists concluded: “Omega-3 fatty acids, B vitamins, and vitamin E supplementation did not affect cognition in non-demented middle-aged and older adults.”
Similarly, evidence for the herbal supplements ginseng and ginkgo biloba fails to stand up to scrutiny. The same goes for practically every other so-called brain-booster. The Natural Medicines Comprehensive Database, a non-commercial organisation that continuously collects and reviews data, failed to find a single proven effective supplement among more than 50 they assessed. They rated a few as “possibly effective” but most simply had “insufficient evidence” to make a judgment.
Lack of proof of efficacy is not, however, proof of lack of efficacy. The large-scale, expensive research needed to show beyond doubt whether something works is usually done only for medicinal drugs, so it’s not surprising that there’s no concrete evidence for the effects of supplements in healthy people.
Supplements are not without risk – they can interfere with medicines and produce nasty side effects, especially if too many are taken. However, a supplement that gives the recommended daily dose of required vitamins and minerals may be a good idea if you feel your brain needs a boost, especially if you think your diet may be deficient in some way. Just consult your doctor if you experience any side effects.