Epilepsy is a disorder of the brain that is characterized by repeated and unexpected seizures or convulsions. Seizures occur as a result of abnormally excited electrical signals in the brain. According to the National Institute of Neurological Disorders and Stroke, epilepsy may be caused by anything that interrupts the normal behavior of nerve cells in the brain. These causes may include head trauma, congenital defects, genetic factors, infection and medical disorders that cause destruction to the brain.
Genetics
Certain types of epilepsy tend to run in families. According to the Mayo Clinic, approximately 500 different genes have been linked to epilepsy. Although having one of these genes does not mean you will necessarily develop epilepsy, it may make you more susceptible to developing it at some point in your life compared with someone who does not possess one or more of those genes.
Congenital Defects
Problems occurring before birth can predispose certain individuals to developing epilepsy. An unborn fetus is susceptible to a number of problems that may damage the brain. For example, oxygen deprivation in the womb, poor maternal nutrition during pregnancy and infections or other medical illnesses in the mother can cause an infant to be born with cerebral palsy, according to the Mayo Clinic. Cerebral palsy--a group of disorders that cause permanent disability related to movement, posture and other neurological functions--is commonly associated with seizures in children.
Brain Injury or Trauma
Physical trauma to the head that causes injury to the brain may cause epilepsy. Head injuries sustained from car accidents, sports-related blows to the head or other accidents can cause irreversible disruptions to normal brain function.
According to the National Institutes of Health (NIH), injuries occurring around the time of birth, such as falls from a bed or other blows to the head, may also damage the brain and lead to the development of seizures in infancy or early childhood.
Infection
Infections in the body can sometimes lead to permanent changes in brain tissue, thereby causing the development of epilepsy at any age. Bacterial or fungal infections may lead to the development of a brain abscess, characterized by brain inflammation and a collection of pus and immune cells, according to the NIH. Brain abscesses can be fatal and may cause serious neurological problems, including epilepsy. Neurosyphilis, a brain infection caused by the Treponema pallidum bacterium, and meningitis, an infection and inflammation of the lining of the brain caused by bacteria, viruses or fungi, can also permanently interfere with normal electrical activity in the brain. Other infections that can cause epilepsy include encephalitis, a brain inflammation most often due to viral infection, and acquired immune deficiency syndrome, or AIDS.
Medical Conditions
Any medical condition that can cause damage to brain cells can theoretically lead to epilepsy. According to the Mayo Clinic, dementia, which is characterized by a loss of cognitive function such as memory and language skills, is one of the leading causes of epilepsy among older people. Heart attacks and stroke are also common causes because they may cut off blood supply to the brain, leading to permanent brain cell damage. The Mayo Clinic notes that stroke causes roughly 50 percent of all epilepsy cases that develop after the age of 65.
