Introduction to Part VII

Abstract

Most of the progress of brain science through the recent decade is based on investigations at the single neuron level. On the other hand, psychological research is carried out at a level of perceptions and actions that involve large portions of an entire brain. What are the organizing principles that make possible the orchestration of the multitude of single cell events into phenomena that appear as coherent “wholes” at the psychological and behavioral level? This is a multifaceted question and to approach it one has first to sort out the different levels on which the issue of “organization” and “architecture” may be considered. One level is the level of the organization of the material substrate which is the carrier of the functions. Neuroanatomists have come to a quite elaborate subdivision of the brain into distinct areas and putative “modules” that gives some hope to the analysability of the whole thing. However, it is by no means clear what the dominant driving factors are in the observed apparent modularity of the brain’s hardware. Many different evolutionary pressures have left their imprint on the structure of the brain, and some important seeming structural features may be mere accidents of evolutionary history.