Time to buff up your brain, to send your synapses to the spa. How about a couple of hours of sudoku? No? Well, fire up your Nintendo DS and pump up your neurons with Dr Kawashima’s Brain Training games — “Keep your brain sharp and in shape.” Nicole Kidman says she does it and she’s always right about everything. Or go on the net and test your brain out at brainmetrix.com before going for a real synapse sauna at braingle.com . Stave off senility by signing up at happy-neuron.com , massage the grey matter between your ears by joining lumosity.com (the “fast, fun and effective way to take care of your brain”), or go to sharpbrains.com to get “high-quality, research-based information and guidance to navigate the brain-training and cognitive-fitness market.” Or, better still, read a good book.

“There’s no empirical evidence that these games produce improvements,” says Nancy Andreasen, one of the world’s most distinguished neuroscientists and author of The Creative Brain. “Saying you spend half an hour a day playing sudoku and you won’t get Alzheimer’s, or playing any of these brain games and you’ll lose less grey matter than somebody who doesn’t — well, nobody has ever done that study.”

“These games definitely work because you get better at playing them,” says Earl Miller, professor of neuroscience at the Massachusetts Institute of Technology. “The big question is: do these skills generalise to normal everyday thoughts? That hasn’t been studied.”

But don’t despair: Susanne Jaeggi, a psychologist at the University of Michigan, may be able to help. She has devised a brain-training game that actually works. It’s a strange, complex game involving sequences of squares on a computer screen, and it definitely improves “fluid intelligence” — the part of your mind that deals directly with the raw newness of experience or, as defined by Jaeggi, “the ability to reason and to solve new problems independently of previously acquired knowledge”.

And there is some evidence that the games in MindFit (mindweavers.com ) do work. Baroness (Susan) Greenfield, director of the Royal Institution, says it does. Short-term memory and basic reaction time are said to be improved by 20 minutes’ play three times a week.

The brain is not, as the brain trainers like to say, a muscle. It is a 1.3-kilogram crème caramel-like mix of fat, water and proteins driven by electricity and chemicals called neurotransmitters. As far as we know, it is, unless it belongs to Kerry Katona, the most complex thing in the universe. It’s made to last, at best, about 100 years. It shrinks and deteriorates with age. By the time you’re 30 you’re probably past your intellectual peak. This is a problem, as we’re living longer and longer, and the danger is that we’ll just get stupider and stupider.

It’s a particular problem for baby-boomers, the large, rich, spoilt generation born after the second world war. They’ve had everything, they run the world, but now they’re in their fifties and sixties. They love themselves to bits. But the selves they love are just so many crème caramels soon to pass their sell-by date. Already they can see the signs. Why did you leave your phone in the freezer? Why do you lose your glasses six times a day? These are symptoms of age-associated memory impairment (AAMI). It happens to everybody, but the boomers didn’t think it would happen to them. If brain- enhancing tactics are suddenly fashionable, it’s because of boomer self-love.

Perhaps, in desperation, they’ll take supplements said to improve brain function — co-enzyme Q10, ginseng, bacopa. Or perhaps they’ll look on the bright side: the brain, though unquestionably mortal, is surprisingly resilient. We’ve known this since 4.30pm on September 13, 1848. It was at that moment than an iron rod an inch-and-a-quarter thick and 3ft 8in long was blasted through the head of an American railroad worker called Phineas P Gage. Large parts of his brain were destroyed, but his recovery was almost complete. Much about this story is controversial. But what is clear is that it inspired all subsequent investigations of the brain, from surgery to neuroscience. Gage’s survival, more or less intact, also shows the brain’s staggering ability to work around problems.

There’s one more bright spot. If we work the brain, we can grow new brain cells.

“There is a gradual growing awareness that challenging your brain can have positive effects,” says Dr Gene Cohen, director of the Center on Aging, Health & Humanities at George Washington University. “Every time you challenge your brain, it will actually modify the brain. We can indeed form new brain cells, despite a century of being told it’s impossible.”

So your brain may be rotting, but there should, in theory, be something you can do to keep it reasonably fresh. The important concept here is “brain plasticity”, the ability of the brain to change and adapt.

“We are literally remaking our brains,” writes Andreasen in The Creative Brain, “— who we are and how we think, with all our actions, reactions, perceptions, postures, and positions — every minute of the day and every day of the week and every month and year of our entire lives.”

Yet, even knowing this, there used to be precious little we could do about it, because humans are notoriously averse to having their brains taken out and examined while in use. The electroencephalograph (EEG) — a way of observing brain activity via electrodes on the skull — was of some use. But it was not until the early 1990s, with the development of magnetic resonance imaging (MRI), that we found we could watch the brain actually working. If MRI delivers half of what many people expect it to deliver, these could turn out to be the most revolutionary machines in human history.

These are, be warned, very early days, so any extravagant claims about ways of improving your brain on the basis of evidence from MRI machines are likely to be snake oil.

“There is this over-complicated thing we barely understand,” says Professor Lawrence Parsons at Sheffield University, “because we’re only at the beginning; we’re still looking at the circuit diagrams.”

But — and these may be the most interesting findings of all — there are tentative signs that we are making some headway in discovering something about the most important human qualities of all — insight, inspiration and creativity. These are what make all of us who we are. And, from psychiatry and psychology, we may even have made a start on the understanding of genius. Over the last few years, neuroscientists and psychologists have just begun to focus on all of these most elusive, precious and human characteristics.

At 6pm on August 5, 1949, a fireman named Wag Dodge and his crew found themselves cut off by a wildfire in Mann Gulch River Valley, Montana. A wall of flame was coming towards them at 30mph. Dodge took a match out of his pocket and set fire to the grass immediately in front of him, stepped into the cleared space, covered his face and pressed himself into the ground so that he could breathe the thin layer of air beneath the smoke cloud. The fire rushed over him and he survived. The other 13 members of the crew hadn’t heard his order to do the same. They all died.

Like the story of Phineas Gage, the story of Wag Dodge has become an inspiration to neuroscientists. Why and how did he do what he did under such extreme conditions? “Wag Dodge — he’s a great one,” says Mark Jung Beeman, a professor of psychology at Northwestern University in Illinois. “It was particularly interesting in such a stressful situation. He was at the point where he basically gave up. He must have had some pretty awesome frontal lobes. Normally, high stress would limit creative, flexible or insight-type thinking, but not in this case.” Beeman’s phrase “at the point where he basically gave up” is crucial. Dodge had been struggling to find a way to escape the flames for some time. When, finally, the situation seemed to be hopeless, it is thought he had a moment of relaxation, of giving up, and that moment became his eureka moment.

Most people would call it inspiration, but neuroscientists prefer the more modest title of “insight”. Beeman is one of a group trying to unravel this extremely elusive phenomenon using MRI and EEG. There are two ways of solving problems: analytic and inspirational. With analytic you just plod your way through the work, reasoning your way to the solution. But often you grind to a halt and give up — exactly what Dodge seemed to do.

Up to this point your brain has been working through a limited number of connections, all directly related to the problem at hand. When you stop, the connections loosen; new connections, new possibilities, can be formed. You may even find that some random object — a bird, a tree — somehow inspires you. Finally you reach the eureka moment, you say “Aha!” and your problem is solved.

“It’s not really inspiration,” says Earl Miller. “There’s really no such thing. It’s more like a reconfiguration of old thoughts. I know from my own experience that most of my insight comes when I’m not thinking about a problem. I work until I’m really caught in a rut, and then I take a walk or play music or drift off to sleep and the solution will occur to me.”

Or, in the more technical language of a paper by Beeman and others on the phenomenon, “Although all problem-solving relies on a largely shared cortical network, the sudden flash of insight occurs when solvers engage distinct neural and cognitive processes that allow them to see connections that previously eluded them.”

In fact, the whole process seems to be centred on one small part of the brain: the anterior superior temporal gyrus. This seems to be the point at which bits of information stored far

apart in the brain are brought together. This may be an important clue as to how the brain organises itself. But it’s only the beginning. At Goldsmiths College in London, Dr Joydeep Bhattacharya says the real issue is not the “Aha!” moment itself, but the way it is produced in the brain and how we recognise it.

“We need to know the brain processes involved, to find how this moment is strong enough to reach consciousness. We know insight does not come from the sky.”

This is the problem with all neuroscience.

We don’t really know what we are seeing

when we watch the brain work. Is it the thing itself — the thought, the flash of insight — or just an aspect of it, the bark rather than the dog? “We’re just not at the point where we can

answer these big interpretive questions,” says Lawrence Parsons at Sheffield.

Parsons himself has conducted some of the most extraordinary experiments in an attempt to track the creative pathways of the mind. He has had tango dancers in his MRI machine. Of course, they couldn’t actually tango, but he did provide a board on which they could do some of the steps. He has also worked on musical improvisation, with Jarvis Cocker, among others, stuck inside his machine. He came up with plenty of information about what parts of the brain lit up. But at this point there’s not much we can do with it. Neuroscience lacks a big theory.

“It may be 300 years before we can do things like enhance our creativity,” says Parsons with a gloomy chuckle. “Some say in 20 years we can make you smarter, but I’m a pessimist.”

There is one important link between musical improvisation and the “Aha!” moment that saved Wag Dodge’s life. Improvisation was found to be accompanied by “a dissociated pattern of activity in the prefrontal cortex”. The prefrontal cortex is to the brain what a conductor is to an orchestra. It pulls the whole show together. In humans it is a third of the whole brain, compared with around 5% in dogs and cats. If you want to find where the thing you call “me” is located, the prefrontal cortex would be a good place to start.

The point about that “dissociated pattern” is that it echoes the loosening of connections that precedes the “Aha!” moment. Insight and creativity, perhaps even genius, do seem to be linked to a brain that can disorganise itself and freewheel, making new and unexpected connections. As Nancy Andreasen puts it, the creative act may “begin with a process during which associative links run wild, creating new connections, many of which might seem strange or implausible. The disorganised mental state may persist for many hours, while words, images and ideas collide. Eventually order emerges, and with it the creative product”.

So, with that in mind, answer this question: how many uses can you think of for a brick? Or this: what would happen if people no longer needed to sleep?

These were questions asked in psychological tests specifically designed to measure creativity. They have been attacked as far too subjective. But they do point to a crucial way of defining creativity. If you are now idly imagining dozens of uses for a brick or the novelties of a sleepless world, then you are probably a divergent thinker. If, instead, the questions make you impatient — a brick is for building walls, dammit — then you are a convergent thinker.

Divergent thinkers habitually wander around their own minds, looking for links, however absurd or surreal. Convergent thinkers look for the one correct answer. The discovery of the structure of DNA by Watson and Crick in 1953 was a clear example of convergent thinking — the one correct answer was a double helix.

Meanwhile, on August 10, 1788, one of the greatest of all examples of divergent thinking came into the world. It was Mozart’s last symphony, the Jupiter, and the final movement is not an answer: it is an explosive assertion of the joy of our apparently limitless creativity. If anybody was a diverger, it was Mozart.

But, of course, creative divergers who can think of 101 uses for a brick are treading a fine line. There has always been a romantic link between madness and genius, and too much divergence can undoubtedly drive you crazy. What science we now have suggests that the link might be true. Oddly, however, high creativity has not so far been found to be linked with schizophrenia, as most people expected, but with mood disorders — notably bipolar disorder or manic depression.

The link has been made by several highly authoritative studies, both by leading American scientists. Kay Jamison, a professor of psychology at Johns Hopkins University in Baltimore, studied poets, playwrights, novelists, biographers and artists and found 38% had been treated for an affective illness — ie, mood disorder.

Joseph Schildkraut, a Harvard psychiatrist, studied 15 abstract-expressionist painters from the 1950s — 50% had psychiatric issues, mainly mood disorders. And Nancy Andreasen studied students at the Iowa Writers’ Workshop, the leading school of its kind in the world. Again there was a phenomenally high percentage of mood disorders.

Andreasen admits she was looking for schizophrenia. This did not mean she expected the students to be full-blown schizophrenics — this is an illness that can destroy the sort of high-level functioning required for true creativity. But she did expect to find schizoid relatives and tendencies. But bipolarity seemed to be the primary condition of the smart young writers.

So what, you might wonder, does all this mean for you, a boomer with brain rot who sometimes leaves his phone in the freezer and his glasses God knows where? What must you do?

The short answer — and the one on which all are agreed — is: use it or lose it. The plasticity of the brain means that it is able, in the face of injury or decay, to find ways of adapting itself to preserve strong patterns of activity. So, if you play chess all the time, you probably will be almost as good at 80 as you were at 40. You would probably also be almost as good at Dr Kawashima’s Brain Training games. But so what? Read books, good books — nothing works better.

The longer answer is that there are potentially beneficial techniques suggested by our still- limited knowledge of the workings of the brain. Jaeggi’s fluid-intelligence game works, but it’s lab-based at the moment and has yet to be adapted for general use.

Nancy Andreasen offers four suggestions to which you should allocate 30 minutes a day — choose a new and unfamiliar area of knowledge and explore it in depth, spend some time meditating or just thinking, practise observing and describing things, and practise imagining. This is quite a punishing workout but it makes perfect sense and, unlike the Nintendo DS, it does seem to describe a better way of life.

Ian Robertson, professor of psychology at Trinity College, Dublin, suggests reading out loud at breakfast, making lists of related objects (say, yellow ones, or those beginning with A), and change hands — brush your teeth with your left hand if you’re right-handed. Again, this makes perfect sense: these tricks make your brain deal with the unfamiliar as opposed to getting locked in old patterns of thought.

But there’s going to be a lot of snake oil on the market in the decades, if not centuries, before we can come up with any more solid prescriptions to save our highest creative selves from brain rot. The brain workout is already as much of a boomer must-do as the body workout. In fact, it’s clearly a lot more important. The best advice I ever heard came from a Spanish neurologist, Damaso Crespo. He said I should do 100 yards a day, not sprinting but walking. But I had to walk with a friend and talk all the time. It’s the walking, the talking and the friendship that feed the brain; the sprint just feeds dumb muscles.

In the end you die, and it seems likely that the miracle of the world inside your particular 1.3 kilograms of crème caramel dies with you. Perhaps you had insight, inspiration, perhaps you created, perhaps you were a genius.

Perhaps, one day, neuroscientists and psychologists will finish their maps and tell us how it’s all done. But will they really?

One last time and date. At 8pm on January 27, 1756, Mozart was born in Salzburg, Austria. He spent most of the next 35 years giving the best ever account in music of why your life is worth living, even though his own ended in poverty, suffering and disappointment. He never had electrodes stuck to his head, nor was he slid inside an MRI machine. And, even if he had been subjected to our mind probes, what would that have told us? Probably what we knew already: that this happened just once.

So forget the Nintendo, forget everything. Listen to what the human mind can do. Brain workouts are all very well but, stripping away the science and the rhetoric, they all come down to the same simple injunction: pay attention, because you pass this way only once.

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