Inside your body's control centre...
There's a mass of wrinkly material in your head, weighing around 1.3kg, which controls every single thing you will ever do. It enables you to think, learn, create and feel emotions, as well as controlling every blink, breath and heartbeat. This fantastic organ is your brain! It’s so amazing that famous scientist James D. Watson once called the brain "the most complex thing we have yet discovered in our universe." Here's why!
Your kitten is in the kitchen. She's about to step on the hot cooker. You have only seconds to act. Accessing the signals coming from your eyes, your brain quickly calculates when, where, and at what speed you will need to leap to stop her. Then it orders your muscles to spring into action. Your timing is perfect, and she’s safe! No computer can come close to your brain's amazing ability to download, process, and react to the flood of information coming from your eyes, ears and other sensory organs. Cool!
Your brain contains about 100 billion microscopic cells called neurons. There are so many, it would take you over 3,000 years to count them all! Whenever you dream, laugh, think, see or move, it’s because minute chemical and electrical signals are racing between these neurons along billions of tiny neuron pathways. Incredibly, the activity in your brain never stops. Countless messages zip around inside it every second – just like a supercharged pinball machine. Your neurons create and send more messages than all the phones in the entire world. And while a single neuron generates only a very small amount of electricity, all your neurons together can produce enough energy to power a low-wattage light bulb. Imagine that!
A bee lands on your bare foot. Eek! Sensory neurons in your skin relay this information to your spinal cord and brain at a speed of more than 240kmph. Your brain then uses motor neurons to transmit the message back through your spinal cord to your foot – to shake the bee off quickly! Motor neurons can relay this message at more than 320kmph. Wow!
Riding a bike seems impossible at first, but soon you master it. How? As you practise, your brain sends ‘bike riding’ messages along pathways of neurons again and again, forming new connections. In fact, the structure of your brain changes every time you learn, as well as whenever you have a new thought or memory. Now that’s clever!
It’s well known that any exercise that makes your heart beat faster – like running or playing a sport – is great for your body and can even help improve your mood. But scientists have recently learned that for a period of time after you’ve exercised, your body produces a chemical that makes your brain more willing to learn. So, if you’re stuck on some tricky homework, go out and run around for a while, then tackle the problem again. You might discover that you’re much more able to solve it!