Causes of Epilepsy

There are many causes of epilepsy, which may vary with the age at which the seizures begin. As a generalisation, it can be said that an epileptic seizure occurs when, due to a sudden unusual release of energy (electrical activity) in the brain, its normal working is disturbed. The brain then fairly rapidly corrects itself and everything soon returns to normal.

From an explanatory point of view, although it may not be strictly medically acceptable, it is useful to divide epilepsy into two types: 1.primary epilepsy – idiopathic epilepsy; and 2.secondary epilepsy.

The seizures in primary epilepsy may be identical to those in secondary epilepsy, but on examination of the brain with today’s techniques, unlike secondary epilepsy, it is not possible to find an abnormality of brain tissue.

For many years this type of epilepsy has been called idiopathic epilepsy, which means that the cause is not understood. There are those who do not like the term ‘idiopathic’ epilepsy, as they argue that there must be a cause; it is just that we don’t know what it is at present. It is probable that an idiopathic epilepsy there are abnormalities of the chemicals in the cells of the area of the brain tissue which is electrically abnormal. These chemical abnormalities are such that from time to time epileptic discharges may be produced. The exact nature of this chemical abnormality had yet to be understood.

Understanding this chemical abnormality is very important for two reasons:
Firstly, it will provide a much better understanding of the nature of epilepsy.

Secondly, it may allow the production of drugs (anticonvulsants, anti-epileptic drugs) specifically aimed at correcting the chemical abnormality.

Secondary epilepsy

Secondary epilepsy is an easier concept to grasp. It means that the symptoms, namely the fits, are secondary, or subsequent to, some obvious abnormality of the brain. In other words, if you could look at the brain itself and examine it, either during life using x-ray techniques like CT or MRI scanning, or autopsy, it would be possible to find an actual abnormality in the brain. The person may have been born with this abnormality of the brain or it may be a scar related to brain damage at birth, a head injury and so on.

It can be fairly easily understood that if there is a structural abnormality of brain tissue, then the brain cells surrounding that abnormality will be somewhat misshapen and possibly functioning abnormally as a result. If you have a scar somewhere on your body, glance at it and notice how it pulls the surrounding skin and tissues in various directions.

Some of the particular causes of epilepsy include:
Anoxia (hypoxia), i.e. lack of oxygen to the brain
Brain damage
Brain tumours
Previous brain infections