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The midlife brain surge that means we DO grow wiser as we get older
By Marianne Power
Last updated at 10:20 AM on 27th July 2010
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2010.04.15
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Ever traipsed to the shops only to find once there you've completely forgotten what you went for? Or struggled to remember the name of an old acquaintance? For years we've accepted that a scatty brain is as much a part of ageing as wrinkles and grey hair. But now a new book suggests we've got it all wrong. According to the Secret Life Of The Grown-up Brain, by science writer Barbara Strauch, when it comes to the important stuff, our brains actually get better with age. In fact, she argues that a raft of new studies have found that our brain hits its peak between our 40s and 60s - much later than previously thought. Furthermore, rather than losing many brain cells as we age, we retain them, and even generate new ones well into middle age. For years it's been assumed that the brain, much like the body, declines with age. The accepted view is that we gradually lose brain cells - up to 30 per cent of our neurons - as we get older, hence the forgetfulness, lack of focus and mental slowness we associate with senescence. Getting better with age: Job-related studies found older people performed better than their younger colleagues
But the longest, largest study into what happens to people as they age, the Seattle Longitudinal Study, suggests otherwise.
This continuing research has followed 6,000 people since 1956, testing them every seven years. It has found that, on average, participants performed better on cognitive tests in their late 40s and 50s than they had in their 20s.
Specifically, older people did better on tests of vocabulary, spatial orientation skills (imagining what an object would look like if it were rotated 180 degrees), verbal memory (how many words you can remember) and problem solving.
Where they fared less well was number ability (how quickly you can multiply, add, subtract and divide) and perceptual speed - how fast you can push a button when prompted.
However, with more complex tasks such as problem-solving and language, we are at our best at middle age and beyond. In short, researchers are now coming up with scientific proof of what we've all known for years - we do get wiser with age.
Meanwhile, job-related studies have found that middle-aged people out-perform younger ones.
In two trials, air traffic controllers and pilots were put simulators to see how they responded to demanding tasks and emergencies.
While the younger colleagues were a little bit faster in their reaction times, the experienced professionals did as well or better in actually doing the job at hand — keeping the planes apart.
So what is it about our older brain that is so good? Traditionally, neuroscientists thought that millions of our brain cells died as we aged.
Now, new studies show that while we can lose brain connections if they are unused, we keep most of our brain cells for as long as we live.
This is because their brains are less susceptible to surges of dopamine — a hormone that can lead to impulsive decisions in young people.
Speaking at an international conference in Edinburgh, Professor Dilip Jeste from the University of California said: ‘The elderly brain is less dopamine-dependent, making people less impulsive and controlled by emotion.
‘Older people are also less likely to respond thoughtlessly to negative emotional stimuli because their brains have slowed down compared to young people. This, in fact, is what we call wisdom.’
Other good news is that we keep our long-term memory with age. True, as we get older our short-term memory deteriorates. The problem is not that the information
has vanished, but that you have trouble retrieving it because we have so much other information stored in our brains — it’s like trying to finding the right book in a huge library.
However, our long-term memories survive. Research by the Mount Sinai School of Medicine in New York looked at the effect of ageing on the brains of rhesus monkeys.
In older monkeys, the brain lost half of message ‘receptors’ responsible for learning
new things, but nearly all those associated with long-term memory remained intact.
And even though we may have more responsibilities and stresses, neuroscientists are finding that we are happier with age. A recent U.S. study found older people were much better at controlling and balancing their emotions.
It is thought that when we’re younger we need to focus more on the negative aspects of life in order to learn about the possible dangers in the world, but as we get older we’ve learnt our lessons and are sub-consciously aware that we have less time left in life — and it therefore becomes more important for us to be happy.
Furthermore, researchers have found that the amount of myelin increases well into middle age, boosting our brainpower.
Myelin is the fatty substance which insulates the brain’s cells (the neurons) and makes the signals between them move faster. It used to be thought that all our myelin was laid down in our childhood and adolescence, but now we know it goes on much longer. American scientists scanned the brains of 70 men aged 19 to 76, and found that in two crucial areas, the amount of myelin peaked at the age of 50, and in some cases in people’s 60s. The study found that the amount of myelin increased in the parts of the brain we use the most — the frontal lobes (which control emotion, risk-taking and decision-making) and the temporal lobes (responsible for language, music and mood). The neuroscientist who led the trial said this increase in myelin can boost our brain’s ability by up to 3,000 per cent, and is ‘the brain biology behind becoming a wise middle-aged adult’. Scientists have also found that as we age, we start to use both sides of our brains instead of just one — a skill called bilateralisation. For example, studies in which volunteers learned pairs of words revealed that younger adults used only their right frontal lobes when recalling the two words, while older adults used both the left and right side. Scientists compare this to lifting a chair with two hands rather than one. Drawing on these extra brain reserves is why older people can get to the point of an argument faster than a 20-year-old, and why they can analyse situations more accurately and solve problems. Last month, U.S. scientists also found that the decisions we make when we are older are much better. Researchers looked at the brain scans of 3,000 Californians between 60 and 100 and found that older people were more rational and wise in their solutions to problems. GO JOGGING SWIG A DAILY PINT OF BLUEBERRY JUICE LEARN THE FLUTE
HOW TO KEEP A SHARP MIND
More than diet or crosswords, exercise is the most important thing you can do for your brain. Exercise strengthens a section of the hippocampus, called the dentate gyrus, which helps to build new neurons, strengthen and build myelin and increase brain volume — even in old age. Scientists at Columbia and Cambridge Universities have found that a regular jog leads to the growth of new brain cells. This could be linked to the increase in blood flow to the brain or higher levels of hormones released while exercising.
When it comes to boosting brain power, doctors generally agree that a diet rich in fruit and veg is best. Researchers in the U.S. have found that a pint of blueberry juice a day boosts pensioners’ memory by up to 40 per cent. The scientists attribute the improvements to compounds called anthocyanins, which are thought to make it easier for messages to pass between brain cells.
To keep your brain sharp, you should try to learn new things — such as a musical instrument. This can boost IQ by as much as seven points, say Swiss scientists. Lutz Jancke of the University of Zurich says: ‘Even in people over the age of 65, after five months of playing, there were strong changes in the brain. The parts that control hearing, memory, and the part that controls the hands all become more active.’
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