The modular organization of the cerebral cortex: Evolutionary significance and possible links to neurodevelopmental conditions

• Published in: Journal of comparative neurology (1911) Vol. 527; no. 10; pp. 1720 - 1730
• Main Authors: Casanova, Manuel F., Casanova, Emily L.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01-07-2019; Wiley Subscription Services, Inc
• Subjects: Animals; Biological Evolution; Cerebral cortex; Cerebral Cortex - anatomy & histology; Cerebral Cortex - physiology; connectivity; Humans; Information processing; Mental disorders; minicolumns; module; Neural networks; Neural Pathways - anatomy & histology; Neural Pathways - physiology; Neurodevelopmental disorders; Neurodevelopmental Disorders - physiopathology; Neurons - cytology; Neurons - physiology; system theory; minicolumns; cerebral cortex; connectivity; module; system theory
• ISSN: 0021-9967; 1096-9861; 1096-9861
• DOI: 10.1002/cne.24554

The recognition of discernible anatomical regularities that appear to self‐organize during development makes apparent the modular organization of the cerebral cortex. The metabolic cost engendered in sustaining interneuronal communications has emphasized the viability of short connections among neighboring neurons. This pattern of connectivity establishes a microcircuit which is repeated in parallel throughout the cerebral cortex. This canonical circuit is contained within the smallest module of information processing of the cerebral cortex; one which Vernon Mountcastle called the minicolumn. Plasticity within the brain is accounted, in part, by the presence of weak linkages that allow minicolumns to process information from a variety of sources and to quickly adapt to environmental exigencies without a need for genetic change. Recent research suggests that interlaminar correlated firing between minicolumns during the decision phase of target selection provides for the emergence of some executive functions. Bottlenecks of information processing within this modular minicolumnar organization may account for a variety of mental disorders observed in neurodevelopmental conditions.
A canonical circuit links cells in modular arrangements throughout the cerebral cortex. The repetitive nature of this construct allows for a simplified design enabled by limited resources. Weak linkages between units provide for versatility in adapting to environmental exigencies.