ABSTRACT
In 1892, a group of prominent Clark University faculty wore a famous path between Worcester and Chicago. They were an impressive group that included biologist C. O. Whitman, neurologist Henry Donaldson, anthropologist Franz Boaz, and anatomist Franklin Mall. But the life sciences were to be transformed as much by the animals as by the men who traveled this path. Rats were, and for many questions still remain, the modern animal model through which animal research provides an experimental foundation for human psychology. Adolf Meyer first used albino rats in Donaldson's Chicago laboratory in 1893. Instead, under the influence of American functionalism and pragmatism, he argued that progress in treatment was possible only if the whole patient were considered. Meyer's research included a strong comparative dimension anchored in the concept of evolution. For Meyer, the functional correlates of the progressive loss of independence to supra-segmental control were complexity and neural plasticity manifest in consciousness.
