The columnar organization of the neocortex

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• Nervous systems, including vertebrate and invertebrate brains, demonstrate modular organization.
• The neocortex exemplifies this with its columnar organization, where classical cytoarchitectural areas comprise smaller, iteratively repeated local neural circuits.

Purpose of the Study:

• To explore the principle of modular organization in nervous systems.
• To understand how local neural circuits form modules within neocortical areas.
• To investigate the formation and function of distributed systems through modular connections.

Main Methods:

• Analysis of the structural and functional properties of neural modules.
• Examination of connectivity patterns between modules within and across brain entities.
• Investigation of how modular subsets form distributed systems.

Main Results:

• Modules within neocortical areas share basic internal design and operation but can vary in cell type, number, and connectivity.
• Modules are grouped into larger entities by dominant external connections, particularly evident in sensory and motor areas.
• Interconnected modular subsets form nested distributed systems, enabling complex, distributed functions.

Conclusions:

• The modular and columnar organization is a fundamental principle in brain design.
• Distributed systems arise from the specific linkages between modular subsets across different brain entities.
• Cortical areas can participate in multiple distributed systems, highlighting the brain's complex, interconnected nature.