Evoked potentials are potentials that are derived from the peripheral or central nervous system. They are time locked with an external stimulus and can be influenced by subjective intentions. Evoked potentials have become increasingly popular for clinical diagnosis over the last few years. Evoked potentials from the visual system are used by ophthalmologists in order to localize the abnormalities in the visual pathway. The otologists are mainly involved in brainstem auditory evoked potentials, while the pediatricians, neonatologists, neurologists and clinical neurophysiologists make use of multimodal stimulation. The psychiatrists and psychologists, generally, examine the slow potentials such as P300 and CNV. Anesthesiologists use short latency somatosensory and visual evoked potentials in order to monitor the effectiveness of the anesthesia. Pharmaco evoked potentials are very promising measures for the quan tification of the effectiveness of drug action on the cerebral cortex. Urologists are more and more involved in pudendal somatosensory evoked potentials and in the intensive care unit evoked potentials are used in order to monitor the functional state of the central nervous system of the patient. This overwhelming number of examinations and exam ina tors clearly demonstrates the need for guidelines and standardization of the methods used. The evoked potential metholody is restricted by the relative poor signal to noise ratio. In many diseases this signal to noise ratio decrease rapidly during the progression of the illness. Optimal technical equipment and methodology are therefore essential.

J.P.C. de Weerd Evoked potentials are the electrical voltage fluctuations which can be recorded from parts of the nervous system in response to stimulation of sensory modalities. One may distinguish between evoked potentials from the peripheral and the central nervous system. For the latter type a further subdivision can be made into spinal, brainstem, and cortical evoked potentials, according to the (assumed) structures from which the responses derive. Another possible subdivision can be made with respect to the specific sensory ffiodality which is stimulated. Accordingly, one has auditory, somatosensory, visual, gustatory and olfactory evoked potentials. At the present time, the former three types of evoked potentials are the ones that are commonly measured in diagnostic procedures. Yhe corresponding sensory systems are relatively easy to stimulate, for example by means of an acoustic click, abrief electrical shock or a reversing light pattern. In contrast, stimulation of the olfactory and gustatory systems has proven to be technically and physiologically difficult and research in these areas is still in an early stage.

Evoked potentials have been used for decades to assess neurologic function in outpatient studies and are now routinely used in the operating room during surgery. Illustrated Manual of Clinical Evoked Potentials is a modern, practical guide to performing these studies and interpreting the results. The book is uniquely organized as a singular resource that provides the necessary background for understanding and conducting evoked potential studies. It functions as a multi-purpose text, atlas, and reading session, with numerous examples of studies and findings and discussion of key takeaways. Divided into five chapters, the book opens with an introduction to the basics of data acquisition and interpretation that lays the foundation for the modality-specific chapters that follow. The next group of chapters are in-depth reviews of visual, brainstem auditory, and somatosensory evoked potentials. Each of these chapters lays out the specifics of the modality and study protocol with examples to show how things should—and should not—be done. Sample studies with discussions about how to interpret them highlight a particular aspect of normalcy or pathology. Imaging correlates are provided to emphasize salient points and offer perspective. The final chapter is an overview of the use of evoked potentials during surgery with imaging and case discussions to introduce the reader to this very important application. Key Features Detailed review of methodology of evoked potential studies Many examples of actual patient studies with imaging correlates Interpretation of each evoked potential study presented in detail “Reading session”-like discussion of each example Special chapter on evoked potentials in the operating room

This book covers all aspects of evoked potentials (EPs) utilized clinically in evaluating the functional integrity of somatosensory, auditory, motor, and visual pathways in the nervous system. It explores techniques needed to correctly perform EPs, and discusses these clinical neurophysiological tests that are performed in academic institutions and large community hospitals. Concise and comprehensive, this case-study rich text is divided into five chapters. Beginning with basic principles of evoked potential recording, the first chapter discusses signal enhancement and limitations of signal averaging. Chapter two then provides an overview of brainstem auditory EPs. Subsequent chapters then present visual EPs and somatosensory evoked potentials. Finally, the book concludes with clinical applications of transcranial magnetic stimulation, as well as a brief discussion of the techniques of transcranial electrical motor evoked potentials during intraoperative monitoring. Clinical Evoked Potentials: An Illustrated Manual functions as an essential reference for neurologists neurosurgeons, anesthesiologists, clinical neurophysiologists, and EP technologists, who are involved with the recording and interpretation of EPs primarily for diagnostic purposes.

Written by experts with extensive clinical and scientific experience, this comprehensive textbook presents the state of the art in auditory evoked potentials. Opening chapters explain the nature of electrical fields that generate surface recorded potentials, summarize the imaging modalities that complement evoked potential studies, and review acoustics and instrumentation. Major sections examine the anatomy and physiology of the auditory periphery, brainstem, and cortex and the principles and clinical applications of auditory, myogenic, visual, somatosensory, and vestibular evoked potentials. Chapters present hands-on laboratory exercises and clinical case studies. A full-color insert includes 3D images from multi-channel evoked potentials and functional imaging.

An essential guide to designing, conducting, and analyzing event-related potential (ERP) experiments, completely updated for this edition. The event-related potential (ERP) technique, in which neural responses to specific events are extracted from the EEG, provides a powerful noninvasive tool for exploring the human brain. This volume describes practical methods for ERP research along with the underlying theoretical rationale. It offers researchers and students an essential guide to designing, conducting, and analyzing ERP experiments. This second edition has been completely updated, with additional material, new chapters, and more accessible explanations. Freely available supplementary material, including several online-only chapters, offer expanded or advanced treatment of selected topics. The first half of the book presents essential background information, describing the origins of ERPs, the nature of ERP components, and the design of ERP experiments. The second half of the book offers a detailed treatment of the main steps involved in conducting ERP experiments, covering such topics as recording the EEG, filtering the EEG and ERP waveforms, and quantifying amplitudes and latencies. Throughout, the emphasis is on rigorous experimental design and relatively simple analyses. New material in the second edition includes entire chapters devoted to components, artifacts, measuring amplitudes and latencies, and statistical analysis; updated coverage of recording technologies; concrete examples of experimental design; and many more figures. Online chapters cover such topics as overlap, localization, writing and reviewing ERP papers, and setting up and running an ERP lab.