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Pathogenesis and treatment of cerebrovascular disease
THE EEG SOCIETY The pronounced individuality and wide diversity, particularly of the time-relations of these variables, suggest that maturation of the nervous system depends on a large number of almost independent factors, some of which may operate abruptly over rather short periods. Although all the subjects were neurologically normal, there was some indication that certain systemic disorders, such as chronic respiratory complaints and allergies, were associated with distinctive patterns of autonomic response.
11. Effects of sleep deprivation on behaviour, subsequent sleep and dreaming, m R. J. Berger and I. Oswald (Edinburgh). The EEG and eye-movements during noctural sleep were recorded from six males on four base-line nights and four recovery nights following 108 h of sleep deprivation. Compared with the base-line nights, on the first recovery night there was a significant increase from 6 per cent to 26 per cent in the mean percentage of total sleep time during which EEG slow waves of deep sleep were present, associated with a significant decrease from 22.5 to 7.4 per cent in the mean percentage of total time spent in dreaming (determined by duration of rapid eye-movement periods). On the second recovery night the mean dream time percentage increased to 27.5 per cent, representing a 20 per cent increase (which was statistically significant) over the base-line mean of 22.5 per cent.
297
The results are discussed in relation to theories of a "need" for dreaming.
12. The recruiting response in the X-irradiated rat. M. Berry and J. T. Eayrs (Birmingham). X-irradiation of the foetal rat gives rise to abnormalities in cortical growth comprising severe disorganization of laminar structure and a reduced density and abnormal orientation of cell processes. In spite of such changes the wave-form recorded at the cortical surface following stimulation of midline thalamic nuclei was essentially the same as that seen in the normal animal. Dissimilarities between records obtained from differently-positioned cortical electrodes in normal rats were preserved in X-irradiated animals as too were the changes normally associated with variations in the depth of stimulation. Small differences were, however, observed in the parameters of the response in animals showing the greatest structural abnormality, notably a reduction in the amplitude and duration of the negative wave. These findings are of importance in so far as they demonstrate that many of the characteristics of an evoked response do not altogether depend upon the finer structural organization of the cerebral cortex. It is thus implied that the distribution of the "sources" and "sinks" reflected in the sequence of surface positivity and negativity may depend more upon the grosser aspects of thalamocortical interaction than upon any precise intralaminar distribution of synaptic activity.
Electroenceph. clin. Neurophysiol., 1962, 14:294-297
BOOK
REVIEWS
Pathogenesis and treatment of cerebrovascular disease. William S. Fields, Editor (Charles C. Thomas, Springfield, Ill., 1961, 562 pp., $15.00). This volume, the fifth published symposium of the Houston Neurological Society, comprises twenty papers presented at their 1959 Annual Scientific Meeting. The participants, from the United States and Canada, all major investigators in different aspects of cerebrovascular disease, lend authority to the contents of the book and liveliness to the included discussions of the papers. The advantages of varied viewpoints and spontaneity in a symposium are offset by unnecessary duplications and a lack of cohesiveness and completeness. This is valuable reading for anyone interested in cerebrovascular disease. It is a disappointment to electroencephalographers because of the paucity of reference to EEG (not one EEG illustration!) and the lack of appreciation most participants seem to have with regard to the possible contributions EEG can make to the understanding of cerebral pathophysiology.
Following an able and succinct summary of the vascular embryology and anatomy of the brain by Kaplan (State University of New York, Brooklyn), Holman and Moossy (Louisiana State University) present from unselected autopsies a fine though preliminary study of the development of atherosclerosis in cerebral arteries. This parallels but at a later age a similar development in the aorta and coronary arteries. Griffin (Baylor University) summarizes the current lack of definitive knowledge with respect to the "basic biochemical alterations either in composition or metabolites that may be associated with the development of atherosclerosis". Meyer (Wayne State University) gives an excellent review of the principles of cerebral blood flow, the effects of experimental occlusion and hypertensive encephalopathy: his chapter is only marred by the tendency to unsupported generalizations, e.g., about the "therapeutically rewarding" effects of endarterectomy for stenosed arteries. One of the clearest and most informative contributions is the review of the complex
Electroenceph. clin. Neurophysiol., 1962, 14:297-299
298
BOOK REVIEWS
clotting mechanisms and the biochemistry of anticoagulant therapy by Owen and Thompson (Mayo Clinic). Adams and Fisher (Harvard University) present excellent papers on the pathology and clinical syndromes in occlusive disease. Meyer's review of the role of EEG contains good general statements and a fine section on activation, but unfortunately it is without any illustrations and lacks a clear discussion of infarction and the changes in the EEG during the course of such an illness. Burg's description and illustrations of angiography for the diagnosis of extracranial cerebral arterial occlusive disease by the subclavian injection technique developed by Crawford and the subsequent chapter by Crawford, De Bakey and Fields (Baylor University) on the arterial reconstructive procedures for the defects found are exciting demonstrations of medical ingenuity, even though it was pointed out in the discussion that randomized control series must be used to evaluate properly the results of such heroic measures. The same need for controlled study was emphasized in the discussion of Millikan, Siekert and Whisnant's (Mayo Clinic) excellent paper on general medical therapy of occlusive disease, in which they conclude that previous attempted specific treatments - - including stellate ganglion block - - are of no value but that anticoagulants may offer some hope. The section on intracerebral hemorrhage is begun by Fisher with two general papers on the pathology (etiologic factors considered) and clinical symptomatology; he emphasizes the autopsy findings of old hemorrhages, which should revise our prognostic pessimism about recovery from intracerebral hemorrhage. Snodgrass (University of Texas) gives a pedestrian review of the surgical treatment (evacuation) of intracerebral hematomata but the lively discussion, sparked by Rayport (Albert Einstein College), elucidates more clearly the criteria for surgical intervention. In the final section on subarachnoid hemorrhage and aneurysm, Smith and Windsor (University of Virginia) emphasize that they cannot consider saccular aneurysms truly congenital because of the absence of such findings in autopsies of infants of two or younger and that such aneurysms arise out of a defect of or destruction of the internal elastic membrane initially. On the other hand, congenital muscular media defects are embryologically common at arterial bifurcations and "failing to supply a normal support to the internal elastic membrane may be a factor in the common localization of aneurysms at arterial bifurcations". Bailey (Indiana University) reviews the pathology and varied etiologic factors while Ecker (State University of New York, Syracuse) the technique, complications and limitations of carotid and vertebral arteriography. Vandewater (University of Toronto) believes his experience warrants the continued use of hypothermia, not hypotension, when patients are operated on for aneurysms; this was questioned by others. Hamby (University of Buffalo)
describes the various neurosurgical procedures developed for dealing with aneurysms (he only mentions in passing the recent attempts of reinforcement by plastic coating) and his current practices. The final paper by Luessenhop, Mora and Sweet (Harvard University) describes the indications for treatment by cervical carotid occlusion, the occasion for the humorous remark by Murphey: "I am sure by now most of you people think we, in Memphis, spend Mondays, Wednesdays and Fridays tying off arteries and Tuesdays, Thursdays and Saturdays opening them up." It does point to the necessity for controlled study with randomized series of patients (similar to the one now being carried out by McKissock in England according to Sweet) to delineate the truly useful treatments in this difficult field. DANIEL SILVERMAN, M.D. University o[ Pennsyh'ania
Supersensitivity following lesions of the nervous system. - - George W. Stavraky (University of Toronto Press, Toronto, 1961, 210 pp., $10.00). Professor Stavraky's monograph is entirely concerned with the application of one hypothesis to an understanding of various disorders of central nervous function - - namely, Cannon's Law of Denervation. In a paper published in 1939, which has become regarded as a classic, Cannon presented evidence that many peripheral structures develop an exaggerated excitability after their nerve supply has been destroyed. In 1949, Cannon and Rosenbhleth published a much more extensive discussion of denervation-supersensitivity in their book The supersensitivity o/ denervated structures: a law o/ denervation. Nearly all of Professor Stavraky's own research has been directed, during the last thirty-five years, to tests of lhis law within the central nervous system and his book is essentially an account of work from his department, presented in its relation to other relevant research in neighbouring fields. It could be said with some justification that too many physiologists have restricted their attention during recent decades to the results of acute experiments. Today, some neurophysiologists are turning away from such short term phenomena as fatigue, synaptic block and post-tetanic potentiation, to become intrigued by the more time-consuming adjustments of the mammalian nervous system. I am thinking here of Sperry's work on central reorganizations following peripheral nerve crossing, Young's experiments with regeneration of peripheral nerve, the work of Edds and of Hoffman on collateral regeneration after partial injury of nerve trunks and of Eccles' recent examination of the trophic effects of motor nerves upon the muscles that they innervate. In this sense, George Stavraky's monograph makes refreshing reading and of course, it is this aspect of his thinking which gives it a particular clinical importance. The analogues of acute
Electroenceph. olin. Neurophysiol., 1962, 14:297 299
11. Effects of sleep deprivation on behaviour, subsequent sleep and dreaming, m R. J. Berger and I. Oswald (Edinburgh). The EEG and eye-movements during noctural sleep were recorded from six males on four base-line nights and four recovery nights following 108 h of sleep deprivation. Compared with the base-line nights, on the first recovery night there was a significant increase from 6 per cent to 26 per cent in the mean percentage of total sleep time during which EEG slow waves of deep sleep were present, associated with a significant decrease from 22.5 to 7.4 per cent in the mean percentage of total time spent in dreaming (determined by duration of rapid eye-movement periods). On the second recovery night the mean dream time percentage increased to 27.5 per cent, representing a 20 per cent increase (which was statistically significant) over the base-line mean of 22.5 per cent.
297
The results are discussed in relation to theories of a "need" for dreaming.
12. The recruiting response in the X-irradiated rat. M. Berry and J. T. Eayrs (Birmingham). X-irradiation of the foetal rat gives rise to abnormalities in cortical growth comprising severe disorganization of laminar structure and a reduced density and abnormal orientation of cell processes. In spite of such changes the wave-form recorded at the cortical surface following stimulation of midline thalamic nuclei was essentially the same as that seen in the normal animal. Dissimilarities between records obtained from differently-positioned cortical electrodes in normal rats were preserved in X-irradiated animals as too were the changes normally associated with variations in the depth of stimulation. Small differences were, however, observed in the parameters of the response in animals showing the greatest structural abnormality, notably a reduction in the amplitude and duration of the negative wave. These findings are of importance in so far as they demonstrate that many of the characteristics of an evoked response do not altogether depend upon the finer structural organization of the cerebral cortex. It is thus implied that the distribution of the "sources" and "sinks" reflected in the sequence of surface positivity and negativity may depend more upon the grosser aspects of thalamocortical interaction than upon any precise intralaminar distribution of synaptic activity.
Electroenceph. clin. Neurophysiol., 1962, 14:294-297
BOOK
REVIEWS
Pathogenesis and treatment of cerebrovascular disease. William S. Fields, Editor (Charles C. Thomas, Springfield, Ill., 1961, 562 pp., $15.00). This volume, the fifth published symposium of the Houston Neurological Society, comprises twenty papers presented at their 1959 Annual Scientific Meeting. The participants, from the United States and Canada, all major investigators in different aspects of cerebrovascular disease, lend authority to the contents of the book and liveliness to the included discussions of the papers. The advantages of varied viewpoints and spontaneity in a symposium are offset by unnecessary duplications and a lack of cohesiveness and completeness. This is valuable reading for anyone interested in cerebrovascular disease. It is a disappointment to electroencephalographers because of the paucity of reference to EEG (not one EEG illustration!) and the lack of appreciation most participants seem to have with regard to the possible contributions EEG can make to the understanding of cerebral pathophysiology.
Following an able and succinct summary of the vascular embryology and anatomy of the brain by Kaplan (State University of New York, Brooklyn), Holman and Moossy (Louisiana State University) present from unselected autopsies a fine though preliminary study of the development of atherosclerosis in cerebral arteries. This parallels but at a later age a similar development in the aorta and coronary arteries. Griffin (Baylor University) summarizes the current lack of definitive knowledge with respect to the "basic biochemical alterations either in composition or metabolites that may be associated with the development of atherosclerosis". Meyer (Wayne State University) gives an excellent review of the principles of cerebral blood flow, the effects of experimental occlusion and hypertensive encephalopathy: his chapter is only marred by the tendency to unsupported generalizations, e.g., about the "therapeutically rewarding" effects of endarterectomy for stenosed arteries. One of the clearest and most informative contributions is the review of the complex
Electroenceph. clin. Neurophysiol., 1962, 14:297-299
298
BOOK REVIEWS
clotting mechanisms and the biochemistry of anticoagulant therapy by Owen and Thompson (Mayo Clinic). Adams and Fisher (Harvard University) present excellent papers on the pathology and clinical syndromes in occlusive disease. Meyer's review of the role of EEG contains good general statements and a fine section on activation, but unfortunately it is without any illustrations and lacks a clear discussion of infarction and the changes in the EEG during the course of such an illness. Burg's description and illustrations of angiography for the diagnosis of extracranial cerebral arterial occlusive disease by the subclavian injection technique developed by Crawford and the subsequent chapter by Crawford, De Bakey and Fields (Baylor University) on the arterial reconstructive procedures for the defects found are exciting demonstrations of medical ingenuity, even though it was pointed out in the discussion that randomized control series must be used to evaluate properly the results of such heroic measures. The same need for controlled study was emphasized in the discussion of Millikan, Siekert and Whisnant's (Mayo Clinic) excellent paper on general medical therapy of occlusive disease, in which they conclude that previous attempted specific treatments - - including stellate ganglion block - - are of no value but that anticoagulants may offer some hope. The section on intracerebral hemorrhage is begun by Fisher with two general papers on the pathology (etiologic factors considered) and clinical symptomatology; he emphasizes the autopsy findings of old hemorrhages, which should revise our prognostic pessimism about recovery from intracerebral hemorrhage. Snodgrass (University of Texas) gives a pedestrian review of the surgical treatment (evacuation) of intracerebral hematomata but the lively discussion, sparked by Rayport (Albert Einstein College), elucidates more clearly the criteria for surgical intervention. In the final section on subarachnoid hemorrhage and aneurysm, Smith and Windsor (University of Virginia) emphasize that they cannot consider saccular aneurysms truly congenital because of the absence of such findings in autopsies of infants of two or younger and that such aneurysms arise out of a defect of or destruction of the internal elastic membrane initially. On the other hand, congenital muscular media defects are embryologically common at arterial bifurcations and "failing to supply a normal support to the internal elastic membrane may be a factor in the common localization of aneurysms at arterial bifurcations". Bailey (Indiana University) reviews the pathology and varied etiologic factors while Ecker (State University of New York, Syracuse) the technique, complications and limitations of carotid and vertebral arteriography. Vandewater (University of Toronto) believes his experience warrants the continued use of hypothermia, not hypotension, when patients are operated on for aneurysms; this was questioned by others. Hamby (University of Buffalo)
describes the various neurosurgical procedures developed for dealing with aneurysms (he only mentions in passing the recent attempts of reinforcement by plastic coating) and his current practices. The final paper by Luessenhop, Mora and Sweet (Harvard University) describes the indications for treatment by cervical carotid occlusion, the occasion for the humorous remark by Murphey: "I am sure by now most of you people think we, in Memphis, spend Mondays, Wednesdays and Fridays tying off arteries and Tuesdays, Thursdays and Saturdays opening them up." It does point to the necessity for controlled study with randomized series of patients (similar to the one now being carried out by McKissock in England according to Sweet) to delineate the truly useful treatments in this difficult field. DANIEL SILVERMAN, M.D. University o[ Pennsyh'ania
Supersensitivity following lesions of the nervous system. - - George W. Stavraky (University of Toronto Press, Toronto, 1961, 210 pp., $10.00). Professor Stavraky's monograph is entirely concerned with the application of one hypothesis to an understanding of various disorders of central nervous function - - namely, Cannon's Law of Denervation. In a paper published in 1939, which has become regarded as a classic, Cannon presented evidence that many peripheral structures develop an exaggerated excitability after their nerve supply has been destroyed. In 1949, Cannon and Rosenbhleth published a much more extensive discussion of denervation-supersensitivity in their book The supersensitivity o/ denervated structures: a law o/ denervation. Nearly all of Professor Stavraky's own research has been directed, during the last thirty-five years, to tests of lhis law within the central nervous system and his book is essentially an account of work from his department, presented in its relation to other relevant research in neighbouring fields. It could be said with some justification that too many physiologists have restricted their attention during recent decades to the results of acute experiments. Today, some neurophysiologists are turning away from such short term phenomena as fatigue, synaptic block and post-tetanic potentiation, to become intrigued by the more time-consuming adjustments of the mammalian nervous system. I am thinking here of Sperry's work on central reorganizations following peripheral nerve crossing, Young's experiments with regeneration of peripheral nerve, the work of Edds and of Hoffman on collateral regeneration after partial injury of nerve trunks and of Eccles' recent examination of the trophic effects of motor nerves upon the muscles that they innervate. In this sense, George Stavraky's monograph makes refreshing reading and of course, it is this aspect of his thinking which gives it a particular clinical importance. The analogues of acute
Electroenceph. olin. Neurophysiol., 1962, 14:297 299