by
Odds Bodkin

Did you know that your brain is really made up of millions of little biological wires called neurons? And that they all talk to each other with tiny pulses of electricity? Most kids have seen pictures of brains, but if you look at a small piece of brain under a microscope, you’ll see the tiny neurons, all linked together in networks.

There are so many neurons in your brain, they’re hard to count. But here’s an interesting way to imagine how many you have. Let’s say we took a cubic inch of your brain. No, we’re not going to do that, of course, since you need every single part of it. But imagine we could, and I told you to start unraveling the tiny wires in that cubic inch. What’s unraveling? Well, have you ever found a loose thread at the hem of a sweater, and pulled it, and said to yourself, "Oh, no! It won’t stop!" The thread just keeps pulling loose? That’s unraveling.

So I say to you, "We’re going to unravel this cubic inch of your brain to see how densely packed the wires are." I give you the first little neuron string, and tell you to start walking. Let’s say you live on America’s East Coast. "Head west, " I say. And off you walk, pulling out the wires from that cubic inch of brain.

Well, you arrive in California, by the Pacific Ocean. "No, I say, there’s still quite a bit left." So you wrap the little wire around a flagpole and head back east. You arrive at the Atlantic Ocean, but I say, "No, better head back west again." So you find another flagpole, wrap the wire around it, and head west again.

You arrive back in California. "Sorry," I say, "better head back again." You make it all the way back to the Rockies, let’s say around Boulder, Colorado, and I finally say, "Good, you’ve unraveled all the neurons in that cubic inch of brain."

That’s pretty amazing to me. There are 10,000 miles of tiny biological wires in every cubic inch of your brain.

And there are quite a few cubic inches.