Marc Yu is a seven-year old like no other. At the age of two he heard "Mary had a little lamb" at a birthday party, pulled himself up to a piano and played it back flawlessly. A year later he was playing Beethoven from memory. In his first cello lesson at age four he demanded to be taught a Bach Sonata. Today he can play over classical 40 pieces from memory.

In this film will look at how a brain grows from conception to puberty to find out how we can explain the marvel of gifted children. Children like Marc seem to defy the rules of brain development. A child so young should not be able to do things so advanced. Where does this amazing talent come from--is it because Marc started so early and worked hard, or could he have been born with a brilliant brain?

Very little is known about the brains of gifted children, but a Harvard neuroscientist has at least worked out what makes the brains of gifted musicians tick. Gottfried Schlaug, who is also a highly skilled organist (and plays Bach's Toccata und Fuge in our film), has scanned dozens of professional musicians and found that their brains are physically different, specifically tuned for music.

But how do musician's brains get to be so special? Are they born with them or do they acquire them through decades of training?

This question leads the film right into the heart of one of the oldest debates in psychology and biology--is it nature or nurture that makes us who we are, and in the case of gifted children: what is it that makes the genius--genes or environment?

Ellen Winner is a psychologist who has spent 15 years studying gifted children in all fields--art, music, maths, language and overall intelligence. She believes that it certainly takes practice to perfect any skill in a gifted child. But she also believes that gifted children have something extra that cannot be explained by training alone.

It is certainly very important for a child to grow up in a world of stimuli for their brains to thrive. Nothing illustrates this more powerfully than the case of "Genie" a 13 year-old girl who had spent almost her entire childhood locked in a darkened room. Without the input from the outside world her brain simply discarded the neuronal circuits for syntax, which is why Genie never learned the grammar of English. This happened because a growing brain uses a brutal but effective way of fine-tuning its electrical connections--active ones survive, the others don't--it's use it or lose it!

This principle makes the growing brain vulnerable, but also extremely flexible. Given the right stimulation at the right time, the sky is the limit for a young brain. A child can acquire every language on this planet, as long as it hears this language spoken early in life. But it's not just language learning that starts early, as the Granddaddy of all early learning studies has shown: the Abecedarian Project, a unique psychological experiment, hand-picked over 100 babies born into deprived neighbourhoods in North Carolina in 1970. Some kids started as early as six weeks old and they were immersed in cleverly designed learning games based on cutting edge child development research. And the result was astonishing--the stimulation improved the performance of the kids in many ways--language, maths, overall IQ and social intelligence. And later on they obtained better education and jobs than their peers who had not been given the brain workout. What started as an idealistic experiment designed to help disadvantaged children, has now been published in over 200 scientific articles--solid proof that early learning, if done right, is the key to fulfilling the brain's potential.

While stimulation is important for a young brain, it does not account for everything. We all know Intuitively we are all born slightly different from one another. Every kid has certain strengths and certain weaknesses. But today there are many psychologists who deny the very existence of talent. They claim that practice is the thing that makes a genius. Practice is certainly necessary, but is it enough?

Robert Plomin, a behavioural geneticist from London, has spent a large part of his professional life trying to solve the genetics of overall intelligence. He uses twins to separate the effects of nature and nurture on IQ and in his latest research venture, he is scouring a database of 10,000 twin DNA samples for the genes that make the difference in intelligence. The more he looks the more candidates he finds. He says that he'll never find one single gene for genius--it's more complicated than that. He believes that many genes work together to bring out propensities in children, which the child itself can then potentiate by seeking out and modifying environments that foster its abilities. In essence--gifted kids are not just born with aptitude, but appetite.

Ellen Winner takes this idea one step further. She has identified one thing that all gifted children--no matter what their skill--have in common. It's an extreme passion to be good at what they do--which Ellen has christened "the rage to master". She says that although some children can be trained to look like prodigies, the tell-tale sign of truly gifted child is this rage to master. Those kids don't not need pushing, they are pushing everybody else, most of all their parents, who are running along, trying to catch up with the brainpower of their children.

But as delightful as musical prodigies are--childhood does not last forever. And if you're no longer a child, you're no longer a prodigy. The simple act of growing up deprives a prodigy of the very thing that defines it. If puberty is difficult for most children, it is a serious hurdle for gifted ones. Not just does audience expectation change--it is no longer good enough to just play technically beautifully, they are expected do develop their own style--and it's also a time when they question the invariably strong bond with their parents and mentors.

And while they deal with all the psychological side effects of growing up, the brains of teenagers are in turmoil. Only recently scientists found that, contrary to previous dogma, the brain is not nearly finished in childhood. Around age 12 there is another growth spurt of grey matter, followed by another round of pruning of connections--it's use it or lose it all over again.

Pianist Lang Lang knows a thing or two about the pitfalls of puberty, but he made it though this difficult period and is now one of the most successful concert pianists on the planet. And he is also Marc Yu's hero. Not just did Lang Lang agree to be filmed, he also played a duet with Marc, which truly made Marc's day. And to top things off Lang Lang had a big surprise in store for Marc--the offer to play Carnegie Hall with him in two years' time--if he practices enough!