Which one of the following in the characteristic feature of juvenile myoclonic epilepsy

Infantile spasms occur in clusters usually on waking - It&;s characterized by a combination of salaam spells ( sudden dropping of the head and flexion of arms ) - Prognosis for complete mental development is poor -vigabatrin is the drug of choice . Juvenile myoclonic epilepsy (JME) is the most common generalized epilepsy syndrome. It is also called Juvenile Myoclonic Epilepsy of Janz. It typically begins in adolescence. Teens with JME do not have other developmental problems. Myoclonic seizures (brief shock-like muscle jerks) are the most common type of seizure. They happen sholy after waking. Generalized tonic-clonic seizures occur in nearly all people with JME. The cause is predominantly genetic. An EEG is the most impoant way to diagnose JME. Ref : Ghai , 8th edition ; pg no : 559