Focusing and targeting of magnetic brain stimulation using multiple coils
Focusing and targeting of magnetic brain stimulation using multiple coils
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DOI：
10.1007/bf02522474
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发表时间：
1998-05-01
影响因子：
3.2
通讯作者：
Ilmoniemi, RJ
中科院分区：
文献类型：
--
作者：
Ruohonen, J;Ilmoniemi, RJ
神经元可以被外部施加的时变电磁场激发。使用多个小线圈而不是一个大线圈来实现聚焦磁脑刺激，所产生的感应电场是来自每个线圈的场的叠加。在多通道磁脑刺激中，来自各个线圈的场的部分抵消提供了刺激场的聚焦的显著改善，并且独立的线圈通道允许在不移动线圈的情况下将刺激瞄准在给定点上。分析了在多通道刺激中形成刺激场的问题，并推导出产生具有用户定义形状的场所需的驱动电流的方法。该制剂利用铅领域和最小范数估计脑磁图。使用这些方法，多通道线圈阵列的一些性质进行了检查。计算机辅助多通道刺激皮层将使几项新的研究成为可能，包括快速确定皮层区域，对这些区域的刺激会破坏任务所需的皮层处理。
Neurones can be excited by an externally applied time-varying electromagnetic field. Focused magnetic brain stimulation is attained using multiple small coils instead of one large coil, the resultant induced electric field being a superposition of the fields from each coil. In multichannel magnetic brain stimulation, partial cancellation of fields from individual coils provides a significant improvement in the focusing of the stimulating field, and independent coil channels allow targeting of;he stimuli on a given spot without moving the coils. The problem of shaping the stimulating field in multichannel stimulation is analysed, and a method is derived that yields the driving currents required to induce a field with a user-defined shape. The formulation makes use of lead fields and minimum-norm estimation from magneto-encephalography. Using these methods, some properties of multichannel coil arrays are examined. Computer-assisted multichannel stimulation of the cortex will enable several new studies, including quick determination of the cortical regions, the stimulation of which disrupts cortical processing required by a task.