That's actually pretty accurate. I took a biorobotics/cybernetics class where we learned a lot about how our brains work, so i'll see if I can contribute.

Your brain is divided up into a bunch of lobes, each which perform different tasks. This is where the idea comes from that you only use 10% of your brain. At any given time, you're only using a small part of your brain, but over the course of your life you use all of it. It's a lot like a house, in that you use every room, but most of the time, any given room is unoccupied.

But on the topic of brain speed, when your brain is stimulated a lot, it can speed up to about 40 Hz, although usually it's more like 12 Hz, and when you're asleep, it's a lot lower. But as far as the mechanism that your brain uses to operate, that's actually very well understood. You learn when your neurons strengthen the connections between them, and the way that neurons communicate with each other is rather simple. But you have trillions of neurons, with each one connected to thousands of other neurons, so the complexity of the whole system is astounding.

Quote Originally Posted by SantaClawz
Your brain can actually slow relative time in tense situations. They did a test with a digital number board, in which the numbers were flicking by too fast too see under normal conditions, but for the first time bungie jumper it was easy to distingish the sequence. What is actually happening it you are seeing faster then normal, kind of like a video card, normally you get 32frames per second, but overclocked you get 60fps. This is also why people in tense situations report it feeling like it took place longer then it actually did. Time is just a chemical reaction within the brain anyway.