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Electromyography and Evoked Potentials. Theories and Applications.
the objects to be recognized. Asking " W h y doesn't the eye see better?" will direct our attention to interesting problem q in vision and will help us to understand why the visual system is organized the way it is. There follow a number of reviews dealing with one of the most important themes of the Bishop school: The X,V,W classification of retinal ganglion cells and the way this division is maintained through the geniculate and cortex. Sampling of visual space by the retina is also discussed (Wassle, Levick) since it provides a description of the grain the brain can use for further visual i eformation processing. The section on comparative visual physiology includes contributions by Pettigrew (on the evolution of binocular vision), who examines binocular vision in cats and owls, and by Aitkin, who examines the processing of information in the auditory system with the visual system in mind. Sanderson discusses the paradox of lateral geniculate nucleus function, which concerns the way it appears to go to great lengths, in evolutionary te~,s, to sandwich closely together layers representing each eye, yet at the same time keeps inputs to those layers from each eye functionally and anatomically segregated. The final sections on the visual cortex and on integrative aspects in vision directly tackle the problem whose understanding constituted the long-range goal of the previous studies, namely how the visual system performances can explain perception and (see, for instance, McKay's paper) "what is the task of vision?" Tnese also include a nice pair of papers (Day, Peterhans) on illusory contours and on how cortical cells respond to them. The venue for the search for coherent themes of visual organization seems likely to be at the interface between visual psychophysics, artificial intelligence and neurosciences. "Visual Neuroscience" surely represents an account of our present understanding of vision which is biased towards the parallel nature of visual processing as opposed to the serial hierarchy of Hubei and Wiesel, but represents, nonetheless, essential and very pleasant reading for all those concerned at the research level on how the brain sees. A. C A T r A N E O Rome
Electromyography and Evoked Po',entials. Theories ~.-~d AppUcations. (Advances in Applied Neurological Science~, Vol. 1. A. Struppler and A. Weindl (Editors). Springer-Verlag, Berlin, Heidelberg, Tokyo, New York, 1985, ISBN 3-540-13973-7 270 pp., DM92.00. In recent years, the developments and applications of electrcmyo~raphic and electroneurographic and evoked potential methods he,re helped greasy in giving us insights into the functions of different neural sys~.em~. These advancements raise important questions about the relevance of such methods for clinica~ diagnosis and about the technological refinementa and developments that may t ~ necessary to enable the use of such methods for clinical and diagnostic purposes.
598
The volume "Electromyography and Evoked potentials" reviews the present status of clinical neurophysiology, excluding conventional EEG, keeping an eye on the dual aspect of these techniques, that of research tools and of therapeutic a n d / o r diagnostic tools. The focus is on the central disorders of movement and of posture and locomotion, a field in which both our understanding and the potential for new therapies is steadily growing. Parts I and II of this volume comprise a series of papers reviewing different aspects of the subject, ranging from "Ardmal models of motor disorders" (Wiesendanger), "Abnormalities of Mechanoreceptor-Evoked Electromyographic activity in Central Motor Disorders" (Tatton et al.) and "Akinesia in Parkinsonism" (Narabayashi) to "Concepts in neural control of posture and locomotion" (Lee) a n d "Control of Neural Prostheses" (Hambrecht). The volume is a collection of brief papers (some are in the form of abstracts and are not of much use), so that the number of different contributions gives the reader (most probably the interested reader will be a neurologist) an overview of the field. Part III surveys electromyographic methods and their application in restorative neurology, discussing, inter alia, the clinical applications of spectral analysis c~ electromyography (Lindstrom) in neurogenic and myogenic diseases. The crmical uses of evoked potentials and brainstem reflexes arc ",he subject of Part IV. The uses of cerebral evoked potentials appear to be increasingly important, since these methods are non-invasive and they can identify a variety of focal alterations in neurological patients. In particular, the remarkable length of the somatosensory pathway from peripheral skin to cerebral cortex makes it vulnerable at many different points to a variety of pathological conditions. The paper by Desmedt in this section surveys some basic data on the neural generators of the early somatosensory evoked potential components evoked b y electrical stimulation in the upper limb in man. Auditory nerve-brainstem evoked responses and their use for neurologicaL! diagnosis are discussed by Sohmer. Part V contains papers reporting on different neuropathies and myopathies, including an interesting report on the earliest abnormalities detectable ~ autonomic neuropathies (Satchell and McLeod). To conclude this brief review of the contents of the volume, it should be noted that visual evoked potentials have been completely ignored in this selection of themes of c l i n i c a l neurophysiology. Due to the vast body of literature related to the field of visual evoked potentials, the choice of the editors is understandable, but should have been made more explicit in the rifle, which sounds too gcneral if compare:: with the actual cortents of the volume. Having noted this, this volume will be of interest to the neurologist wishing to update his knowledge on the electrophysiological examinations of centra) motor disturbances. A. C A T T A N E O Rome
Electromyography and Evoked Po',entials. Theories ~.-~d AppUcations. (Advances in Applied Neurological Science~, Vol. 1. A. Struppler and A. Weindl (Editors). Springer-Verlag, Berlin, Heidelberg, Tokyo, New York, 1985, ISBN 3-540-13973-7 270 pp., DM92.00. In recent years, the developments and applications of electrcmyo~raphic and electroneurographic and evoked potential methods he,re helped greasy in giving us insights into the functions of different neural sys~.em~. These advancements raise important questions about the relevance of such methods for clinica~ diagnosis and about the technological refinementa and developments that may t ~ necessary to enable the use of such methods for clinical and diagnostic purposes.
598
The volume "Electromyography and Evoked potentials" reviews the present status of clinical neurophysiology, excluding conventional EEG, keeping an eye on the dual aspect of these techniques, that of research tools and of therapeutic a n d / o r diagnostic tools. The focus is on the central disorders of movement and of posture and locomotion, a field in which both our understanding and the potential for new therapies is steadily growing. Parts I and II of this volume comprise a series of papers reviewing different aspects of the subject, ranging from "Ardmal models of motor disorders" (Wiesendanger), "Abnormalities of Mechanoreceptor-Evoked Electromyographic activity in Central Motor Disorders" (Tatton et al.) and "Akinesia in Parkinsonism" (Narabayashi) to "Concepts in neural control of posture and locomotion" (Lee) a n d "Control of Neural Prostheses" (Hambrecht). The volume is a collection of brief papers (some are in the form of abstracts and are not of much use), so that the number of different contributions gives the reader (most probably the interested reader will be a neurologist) an overview of the field. Part III surveys electromyographic methods and their application in restorative neurology, discussing, inter alia, the clinical applications of spectral analysis c~ electromyography (Lindstrom) in neurogenic and myogenic diseases. The crmical uses of evoked potentials and brainstem reflexes arc ",he subject of Part IV. The uses of cerebral evoked potentials appear to be increasingly important, since these methods are non-invasive and they can identify a variety of focal alterations in neurological patients. In particular, the remarkable length of the somatosensory pathway from peripheral skin to cerebral cortex makes it vulnerable at many different points to a variety of pathological conditions. The paper by Desmedt in this section surveys some basic data on the neural generators of the early somatosensory evoked potential components evoked b y electrical stimulation in the upper limb in man. Auditory nerve-brainstem evoked responses and their use for neurologicaL! diagnosis are discussed by Sohmer. Part V contains papers reporting on different neuropathies and myopathies, including an interesting report on the earliest abnormalities detectable ~ autonomic neuropathies (Satchell and McLeod). To conclude this brief review of the contents of the volume, it should be noted that visual evoked potentials have been completely ignored in this selection of themes of c l i n i c a l neurophysiology. Due to the vast body of literature related to the field of visual evoked potentials, the choice of the editors is understandable, but should have been made more explicit in the rifle, which sounds too gcneral if compare:: with the actual cortents of the volume. Having noted this, this volume will be of interest to the neurologist wishing to update his knowledge on the electrophysiological examinations of centra) motor disturbances. A. C A T T A N E O Rome