Local cortical thickness patterns

It has been known for at least a century that gyri, the outer folds of the cortex, tend to be thicker than the inner folds, called sulci.  But why?  

In a combined computational, analytical, and experimental study, we showed that the mechanics of folding caused homogeneous films, like the cortex, to bifurcate into thick ridges and thin valleys (Holland et al. 2018; Holland et al. 2020).  However, while these patterns are qualitatively similar to those seen in the brain, they actually underpredict the thickness patterns in humans; it is likely that gyri also grow more than sulci, further differentiating their thickness (Wang et al. 2021).  Most recently, we have shown that tangential folds, on the surface of the brain, affect cortical thickness in a similar way to gyri and sulci in both humans (Demirci & Holland 2022) and non-human primates (Demirci et al., submitted).


Holland MA, Budday S, Goriely A, Kuhl E (2018) "Symmetry Breaking in Wrinkling Patterns: Gyri Are Universally Thicker than Sulci." Physical Review Letters


Holland MA, Budday S, Li G, Shen D, Goriely A, Kuhl E (2020) "Folding drives cortical thickness variations." European Physical Journal Special Topics


Wang S, Demirci N, Holland MA (2020) "Numerical investigation of biomechanically coupled growth in cortical folding." Biomechanics and Modeling in Mechanobiology

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Consolini J, Demirci N, Fulwider A, Hutsler JJ, Holland MA (2022) "Bok's equi-volume principle: Translation, historical context, and a modern perspective."  Brain Multiphysics

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Demirci N & Holland MA (2022) "Cortical thickness systematically varies with curvature and depth in healthy human brains."  Human Brain Mapping

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Demirci N, Hoffman ME, Holland MA (submitted) "Systematic cortical thickness patterns in primates suggest a universal physical law of folding."  

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