Disorders of cortical formation according to stages
| Stage | Cause | Disorder |
|---|---|---|
| Proliferative | Decreased proliferation | Microlissencephaly |
| Increased proliferation | Hemimegalencephaly | |
| Abnormal proliferation | Focal cortical dysplasia | |
| Migration | Undermigration | Complete (classic) lissencephaly |
| Overmigration | Congenital muscular dystrophy | |
| Ectopic migration | Heterotopia | |
| Organization | Deranged organization | Polymicrogyria |
| Schizencephaly |