Elastic instabilities in a layered cerebral cortex: A revised axonal tension model for cortex folding

O. V. Manyuhina, David Mayett, Jennifer M Schwarz

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

We model the elasticity of the cerebral cortex as a layered material with bending energy along the layers and elastic energy between them in both planar and polar geometries. The cortex is also subjected to axons pulling from the underlying white matter. Above a critical threshold force, a 'flat' cortex configuration becomes unstable and periodic undulations emerge, i.e. a buckling instability occurs. These undulations may indeed initiate folds in the cortex. We identify analytically the critical force and the critical wavelength of the undulations. Both quantities are physiologically relevant values. Our model is a revised version of the axonal tension model for cortex folding, with our version taking into account the layered structure of the cortex. Moreover, our model draws a connection with another competing model for cortex folding, namely the differential growth-induced buckling model. For the polar geometry, we study the relationship between brain size and the critical force and wavelength to understand why small mice brains exhibit no folds, while larger human brains do, for example. Finally, an estimate of the bending rigidity constant for the cortex can be made based on the critical wavelength.

Original languageEnglish (US)
Article number123058
JournalNew Journal of Physics
Volume16
DOIs
StatePublished - Dec 22 2014

Fingerprint

cerebral cortex
cortexes
folding
brain
buckling
wavelengths
axons
pulling
geometry
rigidity
mice
elastic properties
thresholds
energy
estimates
configurations

Keywords

  • cerebral cortex
  • liquid crystal
  • mechanics

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Elastic instabilities in a layered cerebral cortex : A revised axonal tension model for cortex folding. / Manyuhina, O. V.; Mayett, David; Schwarz, Jennifer M.

In: New Journal of Physics, Vol. 16, 123058, 22.12.2014.

Research output: Contribution to journalArticle

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