The developmental/congenital disorders are a gray area between core idiopathic and core acquired epilepsies, and their inclusion under the term symptomatic epilepsy reflects the inevitably artificial nature of all classification schemes. This chapter talks about epilepsy syndromes, temporal characteristics of acquired epilepsy, and provoked epilepsies. The term 'acquired' is used to refer to symptomatic epilepsies excluding the predominately genetic or developmental causes. The main reason for considering epilepsy a symptom is that there are so many different causes, and it is therefore perhaps ironical to note that the current classifications of epilepsy pay no heed to etiology at all, focused as they are on clinical and electrographic semiology. It is clear that the distinctive natures of the underlying pathological and physiological processes underlying symptomatic epilepsy after acute brain insults are very different from those underlying idiopathic epilepsy, and so are the clinical, therapeutic, and prognostic features.

In this introductory chapter, a classification of the etiology of epilepsy is proposed, and this forms the basis of the sectional divisions in the rest of the book. In constructing such a classification, it is necessary to take cognisance of five particular points: Definitions, Multifactorial cause of epilepsy, Cause versus mechanism, Focal versus generalized epilepsy and Flexibility. The chapter presents the definitions of the epilepsies which are divided into four main categories: Idiopathic epilepsy, Symptomatic epilepsy, Provoked epilepsy and Cryptogenic epilepsy. The ILAE Commission recommended that a classification should be a database forming the basis of a diagnostic manual; the etological schema in this chapter should be viewed as such for instance in relation to the benign focal epilepsies or even the idiopathic generalized epilepsies. It is clear that in the future, as further knowledge accrues, some of these epilepsies may be reclassified and revised.

The control of posture, stance and motion is highly demanding of the peripheral and central nervous system of a creature, especially if this creature is a relatively fast-moving bipedal one with a high center of gravity. With a sustained cerebral hypoxia/anoxia, a tonic phase with or without myoclonia, that is convulsive syncope, appears. Drop attacks of the vertebro-basal circulation are caused by a transient ischemia of the cortical spinal pathways or the paramedian reticular formation. Cataplexia is defined by a paresis of the skeletal muscles due to a sudden emotion. The triggering emotions are usually of a positive nature. Cataplectic attacks are most commonly triggered by sudden laughter. In startle diseases, the physiological startle reaction is pathologically increased and leads, among others things, to a paroxysmal loss of control of the body posture. In typical absence seizures, the semiology and EEG findings strongly indicate the diagnosis of idiopathic epilepsy.

This chapter outlines and defines the epidemiology and etiology of epilepsy, and explains how these issues are closely related to the present systems of defining and classifying epilepsy. It highlights the issues particularly relevant to women. Epileptic seizures are produced by an abnormal rhythmic and repetitive discharge of neurons, either localized to a particular part of the brain (the 'focal' area) or 'generalized' throughout the whole cerebral cortex. Adults may also develop idiopathic epilepsy or epilepsy that is caused by pathologies developed in childhood. Many people suspect a genetic cause for their epilepsy and are afraid that they might pass it on to their children. The chapter describes the major techniques used to investigate epilepsy. New techniques such as single-photon emission computed tomography (SPECT), positron emission tomography (PET), and functional magnetic resonance imaging (MRI) can examine the functioning of patients' brains without the need to perform invasive surgical techniques.

This chapter highlights the current issues in the epidemiology of brain tumors. It describes the classification of brain tumors in epidemiologic studies, the spatial and temporal occurrence of brain tumors, and the risk factors for brain tumors. Metastatic tumors of the brain may be derived from many primary sites and are of clinical significance because of seizures and other neurologic symptoms. The geographic patterns of brain tumor incidence and mortality rates are relatively stable as is found in many other neurologic diseases such as amyotrophic lateral sclerosis (ALS) and idiopathic epilepsy. Traumatic brain injury has long been considered a risk factor for intracranial neoplasia, especially meningioma. The tumors are then usually demonstrated by magnetic resonance imaging (MRI). The onset of seizure in people aged 35-64 must first be evaluated for benign or malignant brain tumor.