Most experts in the field of psychology and biology agree that the mind and the body are connected in more complex ways than we can even comprehend. Research constantly shows us that the way we think affects the way we behave, the way we feel, and the way our body’s respond. The opposite is also true, physical illness, physical exhilaration, exercising, insomnia all affect the way we feel and behave, but also the way we think about ourselves and the world.

Since most of this online text is devoted to the way our mind works (as opposed to our brain), this chapter will focus on the brain, the nervous system, and how these physiological components of our being interact, respond to, and influence our psychological health.