Epilepsy, juvenile myoclonic

A form of epilepsy that occurs between the ages of eight and 26, most commonly in the teenage years.

It is characterized by jerking (myoclonic) movements of the arms and upper torso, without loss of consciousness.

Seizures are most likely to occur while awakening from sleep.

Many children with this disorder are sensitive to light (photosensitive), and may have myoclonic jerks or seizures when exposed to bright light.

Diagnosis is by observation and by EEG.

During a myoclonic seizure, polyspike-wave discharges over a normal EEG background are seen.

Juvenile myoclonic epilepsy appears to be an inheritable genetic disorder, with the gene located on chromosome 6. Treatment is with anti- seizure medications