Lennox-Gastaut syndrome true disease_ontology Lennox syndrome This syndrome is characterized by the presence multiple types of intractable seizures (in particular tonic seizures in sleep, but atonic and atypical absence seizures also occur), cognitive and behavioral impairments and diffuse slow spike-and-wave and paroxysms of fast activity on EEG. DOID:0050561 OMIM:606369 ORDO:2382 A childhood electroclinical syndrome that is characterized by frequent seizures and intellectual disability that present in early childhood. GARD:9912 childhood-onset epilepsy syndrome