Focal-onset seizure focal to bilateral tonic clonic seizure true true A focal seizure may spread to involve wider brain networks, resulting in a focal to bilateral tonic-clonic seizure. This was previously known as a secondary generalized seizure. Consciousness is impaired. Motor components in such a situation include tonic and clonic features. This type of seizure may follow after other focal seizures types, such as focal motor seizures, focal cognitive seizures, focal sensory seizures or focal impaired awareness seizures. Alternatively, the spread in brain networks may be so rapid that no preceding focal seizure type is identified. https://www.epilepsy.com/learn/types-seizures/focal-bilateral-tonic-clonic-seizures-aka-secondarily-generalized-seizures https://epilepsynewengland.org/knowledge-center/types-of-seizures/focal-bilateral-tonic-clonic-seizures