Doctors determine if a person has had a seizure and why the seizure occurred in a number of ways, including acquiring a detailed history of the incident and doing a complete neurological exam, blood tests and an electroencephalogram, which is a test that measures the electrical activity in the brain, states WebMD. Other tests include continuous-EEG monitoring, imaging studies such as an MRI and neuropsychological testing.
Many different conditions cause seizures, Mayo Clinic explains. These include head injuries, low blood sugar, alcohol withdrawal, infections and sudden high fevers, especially in children. Strokes, brain tumors and other brain injuries also cause seizures, but many seizures have no identifiable underlying cause. If a person experiences two or more such "unprovoked" seizures, doctors typically make a diagnosis of epilepsy, which is a neurological disease.
Epileptic seizures occur in two basic forms: focal seizures and generalized seizures, reports Mayo Clinic. Focal seizures usually involve abnormal movements of a single body part or an abnormal sensation, such as a strange taste or smell. Alternatively, they sometimes cause the affected individual to stare blankly into space or perform repetitive movements, such as walking in circles or chewing or swallowing repeatedly.
Generalized seizures include tonic-clonic seizures, which cause rhythmic, jerky movements of the arms and legs, loss of consciousness, and sometimes loss of bladder control, Mayo Clinic notes. Conversely, atonic seizures cause the person to lose all control of his muscles and fall suddenly to the ground. Most people with epilepsy who have repeated seizures experience the same type of seizure each time.