Epilepsy is caused by abnormal activity in brain cells, leading to seizures. A seizure can produce temporary confusion, complete loss of consciousness, a staring spell, or uncontrollable jerking movements of the arms and legs.
Symptoms vary depending on the type of seizure. In most cases, a person with epilepsy will tend to have the same type of seizure each time, so the symptoms will be very similar from episode to episode. Some individuals with epilepsy have many different types of seizures, with different symptoms each time.
It is believed that head injuries are responsible for many cases of epilepsy.