Schizencephaly is a rare congenital cerebral malformation characterized by the presence of linear clefts in one or both hemispheres of the brain, extending from the lateral ventricles to the pial surface of the cortex, and that lead to a variety of neurological symptoms such as epilepsy, motor deficits, and psychomotor retardation.

A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.