The Cognitive Neuroscience of Human Uniqueness

Abstract

Until recently, neuroscientists have lacked powerful means for studying the human brain, and so have relied on studies of nonhuman species for understanding human brain organization. Moreover, the Darwin-Huxley claim that the human mind and brain, while highly developed, are qualitatively similar to those of other species encouraged the concentration of research in a very few “model” nonhuman species. Several recent developments challenge the traditional model-animal research paradigm and provide the foundations of a new neuroscience. First, evolutionary biologists now understand that living species cannot be arrayed along a single, unbroken sequence of phylogenetic development: species can differ qualitatively. Second, neuroscientists are documenting remarkable variations in the organization of cerebral cortex and other brain regions across mammals. Third, new noninvasive methods from histology, neuroimaging, and genomics are making the human brain accessible for direct, detailed study as never before. Finally, these same methods are being used to directly compare humans to other species (including chimpanzees, the species most closely related to humans), providing the foundations of a new and richly detailed account of how the human brain both resembles and differs from that of other species.