, Volume 2, Issue 3, pp 353–360 | Cite as

Clustered organization of cortical connectivity

  • Claus C. Hilgetag
  • Marcus Kaiser
Review Article


Long-range corticocortical connectivity in mammalian brains possesses an intricate, nonrandom organization. Specifically, projections are arranged in ‘small-world’ networks, forming clusters of cortical areas, which are closely linked among each other, but less frequently with areas in other clusters. In order to delineate the structure of cortical clusters and identify their members, we developed a computational approach based on evolutionary optimization. In different compilations of connectivity data for the cat and macaque monkey brain, the algorithm identified a small number of clusters that broadly agreed with functional cortical subdivisions. We propose a simple spatial growth model for evolving clustered connectivity, and discuss structural and functional implications of the clustered, small-world organization of cortical networks.

Index Entries

Rhesus macaque monkey cat cluster analysis neural networks cortical development robustness vulnerability network function small-world networks scale-free networks spatial growth 


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Copyright information

© Humana Press Inc 2004

Authors and Affiliations

  1. 1.School of Engineering and ScienceInternational University BremenBremenGermany
  2. 2.Department of Health SciencesBoston UniversityBostonUSA

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