Building a Picture of the Brain
The brain is among the most complicated material objects in the known universe. Even before the advent of modern neuroscience, it was a commonplace that the brain is necessary for perception, feelings, and thoughts. This chapter focuses on some features of the brain that make it special, features that challenge the picture of the brain as a machine. The brain of an adult human is about three pounds in weight. It contains about thirty billion nerve cells, or neurons. The chapter suggests alternative views to such a picture and shall range over various levels of organization of the brain, from its most microscopic structural aspects to its most abstract functions. Interspersed among the neurons are non-neuronal cells, called glia, that have developmental and physiological functions supporting neuroanatomy and neural activity. One of the most important issues concerns analyzing and understanding the complexity of the brain that underlies its integrative capacities.