As the picture above reveals, the brains of mammals come in a large variety of sizes, shapes, and degrees of complexity. Why are they so varied? In what ways do different brains differ from one another? Do larger brains give greater adaptability to their owners? How are the observed differences in brain's external appearance reflected in their internal structure? Are different brains wired differently?

People who are curious about what brains do and why they are so varied can learn much about the functional meaning of such variety by studying brain anatomy. In the early 1950's there was an increasing interest in the brain by students and scientists as well as by people in general.

Federal and corporate financial support of brain research has grown enormously in the last 5 decades. The number of brain scientists has grown exponentially during this period. It was realized from the start that establishing a basic library of brain specimens of a variety of mammals would provide students with a basic resource to help curious people to understand how the brain is constructed and which circuits were responsible for which functions.

Every scientist who has done brain research, has assembled a number of brains that were sectioned, the sections being stained and mounted on microscopic slides so that the internal structure of different brains could be compared and analyzed. Many such collections now exist all over the planet. At Wisconsin, Michigan State, Ohio State, CalTech, UCLA, UC Irvine, The University of Oregon, The University of Minnesota, Pennsylvania State University,The University of Michigan, UC San Francisco, The University of Washington, Harvard University, The Johns Hopkins University, Washington State University, St. Louis, and many other educational research institutions around the United States have assembled their own brain collections.

At the University of Wisconsin and at Michigan State University, most of the brain specimens represented in this electronic document were assembled over a period of 35 years. This was done to serve as a neuroanatomical resource in support of a large number and variety of comparative physiological and anatomical studies of the nervous system of mammals. The Library of brain collections began at the Laboratory (then, the Department of Neurophysiology; now the Department of Physiology) at the University of Wisconsin in Madison, Wisconsin (see History). It became clear that the Wisconsin Collection, together with that developed at Michigan State University, were destined to be repositories of reference specimens for systematic comparative studies of mammalian brains that could be used to study gross morphology and microscopic brain structure. The specimens in these two collectons were prepared with care and thoroughness and are designed to last as objects of study for decades to come. These collections constitute, therefore, a base of data for understanding how the brain has evolved in mammals. They will provide an anatomical foundation for comparative studies of neural form and function far into the future.

Descriptions of their use:

The sections in these collections can be used to study and to illustrate how cell bodies and fibers of the central nervous system are organized into nuclear formations, and how myelinated fibers are arranged into the fiber tracts and pathways which interconnect the different nuclei of the brain and spinal cord. Study of how nuclei and fiber tracts are differentially organized and enlarged in different mammals reveal how the brain has evolved. Comparative brain study also reveals how an animal's behavior is influenced by specific nuclei and fiber systems, as well as how differential development of different nuclei and fiber systems influence the early development of sensory and motor capabilities in different mammals.

Future Development of the Collections

We believe that the variety of different specimens in our collections are pretty representative of the great variety of living mammals around the planet. One of our primary aims now is to stabilize these collections at a secure location, to publicize them be means of electronic media, and to make them more widely available for researchers, students and teachers. To this end, these collections have been moved to the National Museum of Health and Medicine (NMHM) in Washington DC, where they will be curated and made available for use far into the future. Once stabilized within the National Museum, our collections will be combined with several other major brain collections (including the Yakovlev Human Brain Collection, as well as collections of a wide range of vertebrates) to provide an extremely valuable National Brain Resource.

This National Resource will allow scholars and students to study and learn about the nervous system in detail and in depth. It is the plan that all the specimens in this National Brain Library will be accessible over the Internet, as well as on site, for users from around the world.