The typical symptoms of gray matter heterotopia are seizures, which are directly related to the location of the gray matter and the size of the heterotopia. Patients with gray matter heterotopia may also present with mental retardation, unresponsiveness, or, in severe cases, microcephaly or cerebellar hypoplasia. Some patients with atypical gray matter ectopic symptoms may not be detected, but may be detected during physical examinations or other brain symptoms by MRI or CT. Gray matter heterotopia is usually considered to be caused by abnormal development of the central nervous system during the embryonic period, for which there is no particularly effective clinical solution, and some cases have a tendency to run in families.