Evolu&on  and  development  of  cor&cal  folding  

Reza  Rajimehr  

Cor&cal  folding  

Why  is  the  cortex  folded?  

•  Dispropor&onate  cor&cal  expansion  •  Staying  thin  •  Limited  wiring  

The  effect  of  brain  size  

The  effect  of  body  size  

The  effect  of  encephaliza&on?  

The  effect  of  cor&cal  thickness  

Ontogeny  of  cor&cal  folding  

Variability  of  cor&cal  folding  in  humans  

•  Normal  varia&on  •  Regional  differences  •  Difference  between  leI  and  right  hemispheres  •  No  correla&on  with  age,  sex,  or  brain  weight  •  Correla&on  between  gyrifica&on  and  cogni&ve  func&ons  

•  Changes  in  gyral  complexity  in  pathologies  •  Cor&cal  folding  in  human  twins  

Theories  about  the  forma&on  of  cor&cal  folds  

Grey  maMer  hypothesis  

Compara&ve  anatomy  of  cor&cal  folding