Now, research from Washington University in St. Louis offers new and compelling evidence that a well-connected core brain network based in the lateral prefrontal cortex and the posterior parietal cortex – parts of the brain most changed evolutionarily since our common ancestor with chimpanzees – contains "flexible hubs" that coordinate the brain's responses to novel cognitive challenges.
Acting as a central switching station for cognitive processing, this fronto-parietal brain network funnels incoming task instructions to those brain regions most adept at handling the cognitive task at hand, coordinating the transfer of information among processing brain regions to facilitate the rapid learning of new skills, the study finds.
"Flexible hubs are brain regions that coordinate activity throughout the brain to implement tasks – like a large Internet traffic router," suggests Michael Cole, PhD., a postdoctoral research associate in psychology at Washington University and lead author of the study published July 29 in the journal Nature Neuroscience.This is consistent with the concept of behavioral mode that David Hays and I adopted and adapted from Warren McCulloch.
This is in contrast to concepts of rigid modularity, where the brain is said to consist of quasi-autonomous behavioral modules, each dedicated to a specific perceptual, cognitive, or behavioral activity. These modules are conceived as being wired-in and universal across humans in a manner similar to, say, the skeletal system or the muscles. Barring pathology and injury, everyone's got the same set in the same arrangement. The notion of modes, and of behavioral hubs, allows for an open-ended arrangement of task specific configurations. The patterns of configuration are not wired-in, though many of the configured components would be.
Note: McCulloch was specifically interested in the reticular activating system, which is in the core of the brain and brain stem and is phylogenetically old. The structures pinpointed by Dr. Cole are in the cerebral cortex, which is a much newer structure. Beyond citing McCulloch's model Hays and I had no specific suggestions about other neural mechanisms that might be involved in modal organizing, though we talked informally about the need for such mechanisms.
