a form of epilepsy marked by generalized seizures (absence seizures and some tonic–clonic seizures) that appear to originate near the center of the brain. It is not associated with any particular local anatomical or functional system but instead radiates outward through both cerebral hemispheres. The term was coined in the 1940s by U.S.-born Canadian neurosurgeon Wilder Penfield (1891–1976) and U.S.-born Canadian neuroscientist Herbert Jasper (1906–1999), and its use is restricted primarily to historic contexts.