9. Why can I remember great memories, but not what I ate last week?
Don't worry, you're not going senile. When experience things, we put off a pulse of electrical energy that's fired off to a network of neurons, and they land in our short-term memory and stays there for a few seconds or minutes. From there, that pulse is sent to long-term memory and finally stored in other regions of the brain. But if these neurons communicate with each other over and over, their connection becomes stronger — and is why we can recall those memories quicker than we can those little everyday moments we don't really care about.
11. How our hands move.
This X-ray shows how our bones moves in our hand. Whoa.
12. So THAT'S why!
As we age, the area of our brain that controls emotion and memory loses 5 per cent of its neurons every decade. By the time we're 80, it will have lost about 20 per cent. That's why memories seem to fade over time!