Seizures can occur at the time of injury but they are uncommon and often do not produce permanent epilepsy. There are a few diseases which cause deterioration of the brain for reasons which are only partially understood. These conditions produce failure of thinking and memory called 'dementia'. Unusually they can cause seizures or epilepsy. These conditions include Alzheimer's disease, Pick's disease, Jacob-Creutzfeldt disease and many others rare conditions.
Seizures can occur at any time during the illness but are often late.
Infrequently multiple sclerosis can affect mental function and cause seizures. This is a large group and includes all those in which there is no explanation for the seizures.