In order to discuss how the brain reorganizes itself, we have to discuss how the brain is organized in the first place. I am going to review a little brain anatomy now but if you are interested in brain anatomy I would suggest reading some of the great neuroanatomy sites on the web. I will touch on a few things here.
The brain has two hemispheres that are almost identical to one another. Each hemisphere has 4 lobes with each lobe carrying out specific functions. There are millions of nerves that relay information between the lobes and between the hemispheres like interconnected highways.
The frontal lobes of each hemisphere contain the motor control centers of the brain. Remember the post about the work by Penfield in mapping the motor map in the frontal lobe? If you imagine how the motor map is organized, your mouth and face map is located in your brain near the top of your earlobe with the hand and arm above that. Your trunk is closer to the crown of your head and your feet are mapped deeper between the hemispheres. These maps within the frontal lobes are part of the final pathway to signal movement but there is a lot of sensory input and coordination that has to happen before the motor message is sent out. Imagine that you reach for a Styrofoam coffee cup filled with hot coffee. Your hand does not simply squeeze the cup. Your visual system sees that the cup is soft and full. Your memories tell you how pliable the cup is and what spilled hot coffee feels like. As your arm begins to reach for the cup, your hand is beginning to match the shape of it. This high level complex planning is being carried out mainly in the frontal lobe in the motor association areas. They are just ahead of the motor maps and connect to them. At the very front of the brain near your forehead are areas that control personality and motivation.