Although the advent of MRI impacted significantly our presurgical investigation, ictal semiology with interictal and ictal EEG has clearly retained its roles in localizing epileptogenesis. MRI-identified lesions considered epileptogenic on semiological and electroencephalographic grounds have increased the likelihood of resective surgery effectiveness whereas a nonlesional MRI would diminish this probability. Ictal propagation and the interplay between its source and destination have emerged as a significant component of seizure evaluation over the past 30 years. 1. Seizure Semiology and Epilepsy Evaluation before and Since MRI Ictal semiology and EEG dominated our localization of intractable epileptogenesis prior to the introduction of MRI. Dr. John Girvin and I each attempted to outdo the other in obtaining patient and observer descriptions of the patients’ seizures, guided by the most comprehensive observations and perceptions documented by Wilder Penfield and Herbert Jasper in Epilepsy and Functional Anatomy of the Human Brain [1]. Seizures of the first 3 medically intractable patients operated upon at University Hospital, London originated in the frontal, occipital, and anterior parietal lobes. Similar extratemporal experiences in Montreal and Glasgow (Dr. Girvin) and the Mayo Clinic (WTB) paradoxically sharpened our clinical definition of temporal/limbic epilepsy. In addition to Penfield’s identification for a semiological pattern as representing temporal lobe epilepsy and subsequent description of mesial temporal ictal semiology [2], subsequent studies disclosed that some features such as version and dysphasia could lateralise epileptogenesis within the temporal lobe, enhancing further the semiological role in this evaluation [3, 4]. The works of International League against Epilepsy Commissions on Epileptic Seizure Classification and Terminology have, in sequential fashion, clarified our clinical analyses. The 1981 ILAE Commission classified partial (focal) seizures into simple partial (consciousness preserved) and complex partial (consciousness impaired). This division has encountered clinical and heuristic limitations as it depends upon evaluating an entity—consciousness—that can neither be defined nor assessed. Gloor [5] discusses the several aspects of consciousness presented by philosophers (1713), neuropsychologists, and other neuroscientists and since Hebb [6]. “As none of the attempts at arriving at a scientifically satisfactory concept of consciousness have been successful” [5], neuroscientists have turned to the more tractable aspects
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