Everyone seems to know that we get our signals to breathe, eat, walk, and laugh from our brain. But your brain isn't just a machine that sends signals to the outside world, so to speak - it also communicates within itself. Your brain seems to have this secret little world of its own where it is actually talking to itself all of the time.
Now, it's not that your brain is having fun whispering little jokes and secrets that no one else can hear. No, it's super busy relaying information from the left hemisphere of your brain to the right hemisphere and vice versa in order to keep you alive. It's like there is a big information highway between the two hemispheres of your brain that is always on, unless your brain is split in two, that is.