Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Lennox-Gastaut syndrome ?
    ### Response:
    Lennox-Gastaut syndrome is a form of severe epilepsy that begins in childhood. It is characterized by multiple types of seizures and intellectual disability.  People with Lennox-Gastaut syndrome begin having frequent seizures in early childhood, usually between ages 3 and 5.
    