Recent advances in the understanding of electrophysiological activity within the cerebral cortex and exciting new speculations as to the functional significance of this activity require a parallel reevaluation of the structural pattern of cortical neurons and their processes.
Any discussion of the functional significance of specialized forms of neuronal activity implies consideration of the end to which this activity is ordained. If the end is considered with respect to the "whole" animal, concepts of the functional significance of the cortex are of the order studied by gross cortical ablation and stimulation. This type of investigation has led to the conclusion that the cerebral cortex is related to the perception of sensation, to voluntary movement, and to psychic or association functions. The anatomical correlates of these functions are the fiber pathways linking the cortex to the different systems to which it belongs, be they visual, somesthetic, auditory, motor, or associational.
Colonnier M. The Fine Structural Arrangement of the Cortex. Arch Neurol. 1967;16(6):651–657. doi:10.1001/archneur.1967.00470240089013