Epilepsy surgery has long been and remains one of the areas of clinical neuroscience that best lends itself to a combination of disease treatment and scientific investigation. The surgical treatment of various forms of epilepsy is highly effective in rendering patients seizure-free or markedly improved. At the same time, investigations in the intraoperative and extraoperative setting allow for detailed study of both mechanisms of cerebral organization and cognition, as well as the opportunity to study epilepsy pathophysiology at the single cell, brain tissue slice, and systems levels. This brief overview of epilepsy surgery will outline the history of epilepsy surgery, goals of surgery, criteria used to determine patient suitability, the various types of epilepsy surgery, and anticipated outcomes of these approaches. Research opportunities that are currently being applied during the surgical management of epilepsy patients to study both normal and abnormal brain function, will be highlighted.

Historical background

Prior to the mid- to late nineteenth century, epileptic patients were treated with a variety of surgical treatments including trephination, cauterization, castration and circumcision. Advances in epilepsy surgery were made possible by the parallel discovery of the localization of cerebral functions and the development of tools to map these functions. Stimulation mapping of the mammalian cerebral cortex evolved in the late nineteenth century as a means to experimentally test two opposing theories of cortical localization: the theory of cerebral equipotentiality and the theory of precise localization of different brain functions. Following novel focal stimulation and resection experiments in animals, Flourens concluded in 1824 that the cerebrum was inexcitable and that, although function was located in various parts of the brain, intellectual and perceptual functions were diffusely represented. He was thus the first to propose a theory of cerebral equipotentiality (Flourens, 1824; Tizard, 1959).

Subsequently, on the basis of clinical and pathological data, the opposing view of precise cortical representation of function was hypothesized for language by a group of French scientists including Bouillaud, Broca, and Aubertin and for sensorimotor function by the English neurologist, Jackson. Jackson carried out clinical observations of patients’ ictal symptoms and subsequent postmortem examination of their cerebral lesions in the mid-nineteenth century. Based on his clinicoanatomical investigations, he recognized that partial seizures may have a focal pathological substrate in the brain. His pioneering work provided evidence both for the localization of cerebral function and the focal nature of partial epilepsy.