Rethinking the centrality of brain areas in understanding functional organization

Parcellation of the cerebral cortex into functionally modular brain areas is foundational to cognitive and systems neuroscience. Here, we question the central status of brain areas from the perspectives of neuroanatomy and electrophysiology. We argue that the major ostensible determinants of brain function, such as cytoarchitecture and connectivity, seldom produce convergent parcellations. Brain areas themselves are just one of several equally important organizing principles; others include macroscale gradients, distributed networks, layers, columns and patches. We further argue that the evidence for a close correspondence between areal parcellation and cognitive function is weaker than is generally supposed. Indeed, many important cognitive functions appear to be implemented in a broadly distributed manner, whereas others appear to obey organizations that have little relationship to brain areas, including distributed networks and functional gradients. We conclude by suggesting a set of guiding principles for performing systems and cognitive neuroscience without the intellectual foundation provided by arealization.