The graphics below demonstrate the similarity (although, of course, on a much different scale) of the structure and purpose of the primary brain cell (the neuron) and that of an electrical connection. The brain cell body is similar to the light switch. The axon is similar to the coated wires that connect the switch to the light socket, and the terminal end of the axon (the spot where the nerve impulse is transmitted across the synapse from one cell to another) is similar to the end of the wire that connects to the socket.
Ok, now we have all the technical and hard to understand information regarding brain cells and how they work. Let’s take it to a level that may be much easier to understand. For instance, a car battery is like a brain cell. Without it, the car won’t start and all the other intricate parts of a car engine cannot perform without it. Let’s say you have a battery but the car still won’t start. The first thing you might check is to see if the battery is connected properly. If not, of course the car won’t start and until you connect it properly it won’t. Compare this to a brain cell. If it is damaged it will not make the necessary connection to the impulses and the brain can not function as it was meant to do. This can happen if the Axon (refer to http://tbilaw.com/axon.html for more information on Axons) is the particular brain cell that make that connection possible. This is the cell that transmits impulses or signal from one brain cell to the other. If it becomes damaged due to head trauma it can throw the whole rest of the system off. In return causing injury to the brain.