How sport changes the shape of your brain
In his new book, The Athletic Brain – How Neuroscience Is Revolutionising Sport And Can Help You Perform Better, award winning sports and technology writer Amit Katwala reveals the relationship between neuroscience and sport.
As we repeat actions time and again, a larger portion of our mind becomes dedicated to performing them. This is why the best athletes are the ones who hit the track and train hard as much as possible. There is a downside to all this training though and new research into neuroscience has revealed that too much repeated training can be bad for you, especially in sports like cricket, golf, snooker where ‘the yips’ is a common condition. Neuroscience is much more critical to the progression of sport than you might think. Amit tells us more…
Sport leaves a mark
From the chunky thigh muscles of sprint cyclists to the cauliflower ears of rugby players who’ve spent a career in the scrum, athletic pursuits shape the body to their unique requirements. But that’s not all. Sport also changes the brain – not just how it processes information, but also its actual shape and structure.
This is called neural plasticity – it means our brains are malleable, like plasticine. The brain is made up of billions of individual neurons that ‘fire’ to transmit signals and information. Every time two neurons in the brain fire simultaneously, the connection between them gets stronger, making them more likely to fire together in the future. This is how we learn new information, build new memories, and develop new skills.
As well as making the connections between neurons stronger, neural plasticity also speeds them up. A fatty substance called myelin wraps around frequently used pathways in the brain, like a plastic coating around a copper wire. Myelin transforms dial-up into broadband in the brain. If you repeat an action or a skill millions of times, as elite athletes do to get to the top, then these small changes add up to change the shape of the brain.
Clowns and cabbies
It all started with London taxi drivers. To get a licence to drive a black cab in the capital, they still have to pass a stringent exam called ‘The Knowledge,’ and develop an encyclopaedic knowledge of thousands of London streets and routes. The brains of these human sat-navs actually look different in a scanner. An area called the hippocampus, which is involved in processing spatial relationships and memories, is larger in London taxi drivers than in other members of the population, and its size is correlated to how many years they’ve been in the job. Thousands of hours of navigating London by memory had changed the layout of their brains.
The same thing happens to elite athletes, who have put in thousands of hours of practice to get to the top. In the motor cortex, which controls the movement of the muscles, the size of the brain areas that control different muscle groups will depend on how frequently and precisely they use those muscles.
For example, one study of violinists found that the area of the brain that controlled the fingers of their left hand – which presses down on the strings – was bigger than the area that controlled the same muscles in their right hands. Another found that the hand muscles of elite badminton players are controlled by a bigger area of the brain than in those who had never played a racquet sport.
The layout of the brain is constantly shifting. These changes don’t take long to develop, but they disappear quickly too. One study of people learning to juggle found a difference after just a few months of practicing. Once they stopped juggling again, this difference started to disappear. If you stop practicing a skill, or if you’re out injured, it will start to atrophy just as much as the muscles themselves, and the area of the brain you used to use for it will be slowly taken over by something else. It’s a territorial war. Studies of amputees have found that when they lose a limb, the brain areas adjacent expand into the area. Neural resources are allocated by the general principle of ‘use it or lose it’.
Sometimes that can have alarming side effects. ‘The yips’ is a condition where experienced athletes suddenly lose the ability to perform their skill. It affects people in cricket, golf, snooker, and other sports where repetitive actions are required. Its sufferers are unable to perform with their usual fluidity – their movements become jerky and uncoordinated. The yips have ruined careers, and they tend to strike late. One study of golfers found that those with the yips had spent between 21 and 31 years playing the sport on average.
In some cases, the yips could be caused by the very same mechanism that helps athletes get so good in the first place. The brain area devoted to a particular group of muscles grows with practice. But this means it can start to encroach on other areas of the brain and overlap – causing muscles to contract at the same time. This is called focal dystonia – the brain loses its ability to move certain muscles independently, the same way you might struggle to move your smaller toes separately.
Sports psychologists have tried treating the yips by taking advantage of the brain’s flexibility. Some treatments involve changing the sensory input given to the brain – giving golfers ski gloves to wear while putting, or replacing the ball with a tennis ball can temporarily eliminate the yips. The other options relies on re-learning the skill in a different way, using new muscle groups and brain areas, and allowing the old swollen areas to shrink towards normal. This is why golfers sometimes change their grip, and why some have found success with the controversial belly putter – a completely different way of addressing the ball.
A shortcut to skill?
Neural plasticity is at its peak when we’re young, during so-called ‘critical periods’. This is why we soak up skills like language almost effortlessly as children, before it gets much harder when we get older. It’s also one of the reasons why those who start their sporting careers early on life have more chance of rising to the top.
That could change, though. Daring research has managed to re-open critical periods for learning in rats by electrically stimulating an area of the brain called the nucleus basalis. It’s a long way off, and there are obvious ethical considerations, but in theory it could do the same in humans – helping amateurs and athletes rapidly improve their skills, and change the shape of their brains.
The Athletic Brain – How Neuroscience Is Revolutionising Sport And Can Help You Perform Better by Amit Katwala is released on August 11. Published by Simon & Schuster, £16.99.
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