200 pair telephone cable model of corpus callosum
Your brain is considerably more complex wiring than you may think. The main interconnection between your left and right brain hemispheres has 200 million connections. Thus, each wire pair in this cable would represent on the order of 1 million nerves.
"The corpus callosum is the main transverse tract of fibers that connects the two cerebral hemispheres. It is made of more than 200 million nerve fibers."