A hypothesis on the primate neocortex evolution: Column-multiplication hypothesis

Abstract

A hypothesis is proposed, that the primate neocortex has evolved by the multiplication of cortical columns. As the column size is similar across primate species, it is considered that the columns have multiplied to expand the neocortex during primate evolution. This hypothesis would explain the expansion of neocortical sensory-motor-associational areas and multiple sensory and motor areas which had occurred during evolution. Further, the hypothesis predicts the existence of columns neutral for the fitness, genetic control upon the columns, and intraspecies variations of the columns.