Transcranial Magnetic Stimulation: A Neurochronometrics of Mind
Transcranial Magnetic Stimulation: A Neurochronometrics of Mind
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DOI：
10.1097/01.wnq.0000126267.16108.04
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发表时间：
2004-06
影响因子：
--
通讯作者：
D. Long
中科院分区：
文献类型：
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作者：
D. Long
经颅磁刺激大脑皮层是我们研究人脑功能所用技术的重要组成部分。直到最近，关于人类关键功能的最直接信息都是通过类比对其他灵长类动物暴露的皮质的研究，以及对因其他目的而暴露于异常大脑的人进行的类似研究，通常是肿瘤或癫痫手术。近年来，功能磁共振成像(FMRI)已成为检测清醒行为人脑功能的重要手段。然而，功能磁共振成像只在任务和特定大脑区域的活动之间建立了关联。在某些类型的任务中，这些特定的大脑区域的激活的特异性和选择性是现在非常感兴趣的问题。尽管有这个局限性，功能磁共振成像是所有试图解释人类大脑功能的技术中应用最广泛的。然而，仍然有一个重要的地方直接刺激皮质，而经颅磁刺激为无任何已知脑功能障碍的患者提供了通过闭合颅骨进行皮质刺激的可能性。这本关于这种有趣方法的历史和技术的书对所有在认知领域工作的人和所有对大脑如何工作感兴趣的神经外科医生来说都是真正有价值的。这本书的第一部分涉及检查认知的技术及其历史发展。所描述的技术范围从单个细胞的微刺激到脑电图术和脑磁图术。对直接皮质刺激的局限性进行了认识和讨论，并与经颅磁刺激技术进行了对比。有一篇关于医学中的磁学历史的精彩回顾，其中包括关于法拉第著名理论的发展以及电磁学在医学中的实际和不切实际的应用的大量信息。我们都知道，我们目前对皮质功能的欣赏始于休林斯·杰克逊对癫痫的精确临床研究，以及弗里奇和希齐格的实验，在这些实验中，他们通过电刺激狗的大脑来诱发运动。费里尔扩展了这些观察，并证明了电极的微小运动激活了不同的肌肉。所有神经外科医生都熟悉彭菲尔德和贾斯珀的小矮人。这些神经科学家在20世纪30年代设计的皮质刺激技术至今仍在普遍使用。在进行这些众所周知的皮质定位检查的同时，也有大量关于磁激活大脑功能的实验。我惊讶地得知，在我自己的约翰·霍普金斯医学院的邓拉普是最重要的早期研究人员之一，他证明了磁流可以产生视觉感觉，尽管他们产生的地点尚不确定。直到1985年谢菲尔德大学的经颅磁刺激才成为现实。从那时起，已经做了大量的工作来验证这项技术，了解皮质中发生的事情，并检查具体的皮质效应是什么。与这项技术相关的一系列重要问题。第一个问题是发生的刺激的焦点可能有多大，作者详细研究了这个问题。第二个问题是，反应的产生是实际刺激还是虚拟损伤。另一种可能性是，这种促进作用已经发生。作者讨论了…的影响
Transcranial magnetic stimulation of the cortex is an important part of the armamentarium of techniques we have available to study the function of the human brain. Until the recent past, most direct information concerning critical function in human beings was drawn from analogy with the study of the exposed cortex of other primates and similar studies carried out in human beings with abnormal brains exposed for some other purpose, usually tumor or epilepsy surgery. Recently, functional magnetic resonance imaging (fMRI) has been developed as an important method to examine brain function in awake behaving human beings. fMRI only establishes correlation between a task and activity in specific brain areas, however. The specificity and selectivity of activation of these specific brain areas during some kinds of tasks are a matter of great interest now. In spite of this limitation, fMRI is the most widely used of all the techniques that seek to explain brain function in human beings. Nevertheless, there is still an important place for direct stimulation of the cortex, and transcranial magnetic stimulation offers the possibility of cortical stimulation through the closed skull in patients without any known disorder of brain function. This book on the history and techniques of this interesting method is of real value to all working in the field of cognition and to all neurosurgeons interested in how the brain works. The first part of the book deals with the techniques for examining cognition and their historical development. The techniques described range from microstimulation of individual cells to electroencephalography and magnetic encephalography. The limitations of direct cortical stimulation are recognized and discussed and then contrasted with transcranial magnetic stimulation techniques. There is an excellent review of the history of magnetism in medicine, which includes considerable information on the development of Faraday’s famous theories and the practical and impractical applications of electromagnetism in medicine. We all know how our current appreciation of cortical function began with the precise clinical studies of Hughlings Jackson’s studies of epilepsy and the experiments of Fritsch and Hitzig in which they evoked movement by electrical stimulation of the dog’s brain. Ferrier extended these observations and demonstrated that tiny movements of electrodes activated different muscles. All neurosurgeons are familiar with the homunculus of Penfield and Jasper. The techniques of cortical stimulation devised by these neuroscientists in the 1930s remain in common use today. During the same time that these well-known examinations of cortical localization were being performed, there was extensive experimentation on the activation of brain function with magnetism. I was surprised to learn that Dunlap, at my own Johns Hopkins School of Medicine, was one of the most important of the early researchers and demonstrated that magnetic current could produce visual sensations, although the location of their production was uncertain. Transcranial magnetic stimulation did not become a practical reality until 1985 at the University of Sheffield. Since that time, there has been a significant amount of work done to validate the technique, understand what is happening in the cortex, and examine what the specific cortical effects are. There is a series of important questions related to this technique. The first is how focal the stimulation that occurs may be, and the authors examine this issue in detail. The second is whether the production of a response is actual stimulation or a virtual lesion. Another possibility is that the facilitation has occurred. The authors discuss the implications …