• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of transbhomepageaboutsubmitalertseditorial board
Philos Trans R Soc Lond B Biol Sci. Jan 29, 2000; 355(1393): 91–110.
PMCID: PMC1692723

Anatomical connectivity defines the organization of clusters of cortical areas in the macaque monkey and the cat.

Abstract

The number of different cortical structures in mammalian brains and the number of extrinsic fibres linking these regions are both large. As with any complex system, systematic analysis is required to draw reliable conclusions about the organization of the complex neural networks comprising these numerous elements. One aspect of organization that has long been suspected is that cortical networks are organized into 'streams' or 'systems'. Here we report computational analyses capable of showing whether clusters of strongly interconnected areas are aspects of the global organization of cortical systems in macaque and cat. We used two different approaches to analyse compilations of corticocortical connection data from the macaque and the cat. The first approach, optimal set analysis, employed an explicit definition of a neural 'system' or 'stream', which was based on differential connectivity. We defined a two-component cost function that described the cost of the global cluster arrangement of areas in terms of the areas' connectivity within and between candidate clusters. Optimal cluster arrangements of cortical areas were then selected computationally from the very many possible arrangements, using an evolutionary optimization algorithm. The second approach, non-parametric cluster analysis (NPCA), grouped cortical areas on the basis of their proximity in multidimensional scaling representations. We used non-metric multidimensional scaling to represent the cortical connectivity structures metrically in two and five dimensions. NPCA then analysed these representations to determine the nature of the clusters for a wide range of different cluster shape parameters. The results from both approaches largely agreed. They showed that macaque and cat cortices are organized into densely intra-connected clusters of areas, and identified the constituent members of the clusters. These clusters reflected functionally specialized sets of cortical areas, suggesting that structure and function are closely linked at this gross, systems level.

Full Text

The Full Text of this article is available as a PDF (290K).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Felleman DJ, Van Essen DC. Distributed hierarchical processing in the primate cerebral cortex. Cereb Cortex. 1991 Jan-Feb;1(1):1–47. [PubMed]
  • Goodale MA, Milner AD. Separate visual pathways for perception and action. Trends Neurosci. 1992 Jan;15(1):20–25. [PubMed]
  • Goodhill GJ, Simmen MW, Willshaw DJ. An evaluation of the use of multidimensional scaling for understanding brain connectivity. Philos Trans R Soc Lond B Biol Sci. 1995 May 30;348(1325):265–280. [PubMed]
  • Hilgetag CC, O'Neill MA, Young MP. Indeterminate organization of the visual system. Science. 1996 Feb 9;271(5250):776–777. [PubMed]
  • Jouve B, Rosenstiehl P, Imbert M. A mathematical approach to the connectivity between the cortical visual areas of the macaque monkey. Cereb Cortex. 1998 Jan-Feb;8(1):28–39. [PubMed]
  • Lomber SG, Payne BR, Cornwell P, Long KD. Perceptual and cognitive visual functions of parietal and temporal cortices in the cat. Cereb Cortex. 1996 Sep-Oct;6(5):673–695. [PubMed]
  • Merigan WH, Maunsell JH. How parallel are the primate visual pathways? Annu Rev Neurosci. 1993;16:369–402. [PubMed]
  • Scannell JW, Blakemore C, Young MP. Analysis of connectivity in the cat cerebral cortex. J Neurosci. 1995 Feb;15(2):1463–1483. [PubMed]
  • Scannell JW, Burns GA, Hilgetag CC, O'Neil MA, Young MP. The connectional organization of the cortico-thalamic system of the cat. Cereb Cortex. 1999 Apr-May;9(3):277–299. [PubMed]
  • Simmen MW, Goodhill GJ, Willshaw DJ. Scaling and brain connectivity. Nature. 1994 Jun 9;369(6480):448–450. [PubMed]
  • Tononi G, McIntosh AR, Russell DP, Edelman GM. Functional clustering: identifying strongly interactive brain regions in neuroimaging data. Neuroimage. 1998 Feb;7(2):133–149. [PubMed]
  • Watts DJ, Strogatz SH. Collective dynamics of 'small-world' networks. Nature. 1998 Jun 4;393(6684):440–442. [PubMed]
  • Young MP. Objective analysis of the topological organization of the primate cortical visual system. Nature. 1992 Jul 9;358(6382):152–155. [PubMed]
  • Young MP. The organization of neural systems in the primate cerebral cortex. Proc Biol Sci. 1993 Apr 22;252(1333):13–18. [PubMed]
  • Young MP, Scannell JW, O'Neill MA, Hilgetag CC, Burns G, Blakemore C. Non-metric multidimensional scaling in the analysis of neuroanatomical connection data and the organization of the primate cortical visual system. Philos Trans R Soc Lond B Biol Sci. 1995 May 30;348(1325):281–308. [PubMed]

Articles from Philosophical Transactions of the Royal Society B: Biological Sciences are provided here courtesy of The Royal Society

Formats:

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...

Links

  • PubMed
    PubMed
    PubMed citations for these articles

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...