A large piece of white matter between them consists mainly of axons of cortical neurons

A large piece of white matter between them consists mainly of axons of cortical neurons. The bark is a large command center, and out of the mass of axons, many of its orders emanate from it. The coolest illustration of this concept is a set of artistic representations made by Dr. Greg Dunn and Brian Edwards. Look at the clear difference between the structure of the outer layer of the gray matter crust and the white matter beneath it. These cortical axons can transmit information to another part of the cortex, to the lower part of the brain or through the spinal cord - the superhighway of the nervous system - and into the rest of the body. Let's look at the entire nervous system. The nervous system is divided into two parts: the central nervous system - your brain and spinal cord - and the peripheral nervous system - consisting of neurons that emanate from the spinal cord into the rest of the body. Most types of neurons are interneurons that communicate with other neurons. When you think, in your head a bunch of interneurons are talking to each other. Interneurons are mainly found in the brain. Two other types of neurons are sensory neurons and motor neurons - they go down the spinal cord and make up the peripheral nervous system. These neurons can be a meter long. 

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