The field of barrel cortex research has grown rapidly over the past few years. Today, studies are directed not only at understanding the barrel cortex itself but also at understanding issues in related fields using the barrel cortex as a model system. In the three years it has taken to write this book, over 300 papers have been published on barrel cortex. While this rising tide of information has made writing a challenge, the fundamental studies of the preceding 34 years have provided a solid foundation and context in which to place the new work. Fortunately for me, the story has been enhanced by research in recent years and not entirely rewritten by it.

One of the reasons for writing this book has been the realization that barrel cortex research has matured to a point where a survey and a summary has become possible. The field has been characterized by classic studies that illuminate this and other areas of neuroscience and by a constant innovation in techniques and ideas. In fact, the barrel cortex has served as a test-bed system for several new methodologies, partly because of its unique and instantly identifiable form, and partly because the species that have barrels, the rodents, are the most commonly used laboratory mammal. The classic studies on the basic anatomy and physiology of this cortical area have certainly facilitated subsequent studies on barrel cortex. Two fundamental innovations have driven the field further.