On Mapping and Maps in the Central Nervous System

Abstract

The “Mapping” in the Nervous System is an implicitly manifold definition. The word per se points out one of the general features of the nervous system, the property of being divided in different areas. This property is worth of some detailed consideration. Segregation means a space or structure difference from the immediate neighbourhood. And we can read segregated zones or areas in the central nervous system. In the mean time, segregated areas or regions do not stand as isolated items in a whole. Or, more appropriately, they could, where the whole is a simple envelope of elements or features. However, the obvious requirement of functional coherence in the nervous system implies that segregation does not represent the main trait in the system, and that mutual relation among parts is necessary with the crucial property of connectivity. The parts (the segregated parts) must cooperate, interact and extract a finer, greater and more extensive functional result than that resulting from mere element addition. It is given for understood that a coarser system with reduction of the segregation degree should lead to reduced system ability and flexibility to work out the different tasks and, conversely, that an excess of segregation as area redundancy should lead to uncoordinated and unbalanced system. Parenthetically, redundancy is a fundamental feature implying that a definite function, whatever it is, can be carried out by more than one single network or network configuration and that comparable outcomes can be obtained by different execution paths. In a biological system the current structure stands on longest evolutionary processes and represents established processes as dynamic balance and compromise of diverse biological even conflicting ‘necessities’.