Polymicrogyria (IMAGE) Boston Children's Hospital Caption In polymicrogyria, the cortex of the brain has many irregular, small folds (gyria) and disorganization of its layers, caused by mutations in one of several genes. Many affected children have severe developmental delay, intellectual disabilities, and epilepsy, Credit Richard Smith/Sebastian Stankiewicz, Boston Children's Hospital Usage Restrictions please credit as indicated License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.