The Prefrontal Cortex Makes the Brain a Preadaptive System

In the course of evolution, the prefrontal cortex develops to maximum relative mass in the human brain. That large increase in mass is attributable to the disproportionate development of connective fibers (white matter), rather than cells (gray matter). This points to connectivity as the key to the evolutionary advantage of the human prefrontal cortex. In the light of modern research, it becomes apparent that this cortex, in the human, represents the ultimate embodiment of the capability of the organism to adapt to changes in its environment; that capability rests largely on cortical connectivity. The cognitive code is a relational code, inscribed by connectivity within and between large-scale cortical networks (cognits). In this paper, it is proposed that the prefrontal cortex endows the rest of the cortex with the ability to adapt the organism to its environment in anticipation of predicted changes. This makes the brain a preadaptive organ. Therein is the reason why the executive functions of the prefrontal cortex-mainly top-down attention, working memory, preparatory set, planning, and decision making-all have a critical future dimension. Through its connections with limbic structures and other cortical regions, the prefrontal cortex imparts to the brain its power to preadapt to events in the emotional and cognitive domains.