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Parcellation and area-area connectivity as a function of neocortex size
Mark A Changizi1, Shinsuke Shimojo
1Sloan-Swartz Center for Theoretical Neurobiology, Caltech, CA 91125, USA. changizi@caltech.edu
Brain, Behavior and Evolution
|May 28, 2005
Summary
The number of neocortical areas scales with brain size, and connectivity increases with the number of areas. These findings reveal fundamental principles of neocortical organization.
Area of Science:
- Neuroscience
- Neuroanatomy
- Computational Neuroscience
Background:
- The neocortex exhibits complex organization with numerous distinct areas.
- Understanding the relationship between neocortical size and its organizational principles is crucial.
Purpose of the Study:
- To quantify how the number of neocortical areas scales with neocortex size.
- To determine how the number of area-to-area connections scales with neocortex size.
Main Methods:
- Meta-analysis of data from the neuroanatomy literature.
- Quantitative estimation of scaling relationships for neocortical areas and connections.
Main Results:
- The number of neocortical areas scales with the 1/3 power of gray matter volume.
- The total number of area-to-area connections scales with the square of the number of areas.
- Average neurons per area scale with the square root of the total number of areas.
Conclusions:
- Scaling laws provide constraints for theories on neocortical organization.
- These findings offer insights into the evolutionary and developmental principles governing brain structure.
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