Simultaneous functional MRI and Micro-Magnetic Nervous System Stimulation

摘要 与电刺激相比，微磁刺激(µMS)有几个优势。首先，µMS不支持 需要像电刺激一样的电荷平衡刺激波形。在微毫秒中，既不汇点也不源点 当时变的磁场感应出电流时，它们就存在。因此，µMS不会受到充电的影响 积聚，如电刺激时可能发生的。第二，通过µMS的磁刺激能够激活 具有特定轴突方向的神经元。第三，它是非接触式的，所以生物兼容材料，如对二甲苯 将允许植入，反应最小或没有反应。此外，由于探头可以完全与 脑组织，我们显示了显著减少过度的能量沉积到组织中的问题 磁共振成像(MRI)。 在这项应用中，我们建议为下一代设计、制造和测试微线圈结构 神经系统刺激：微线圈阵列将设计用于皮层刺激，如ECoGs和 脑深部刺激。该阵列将是新颖的，因为它将分配光纤来现场执行 在清醒和行为的动物中记录光遗传钙通道，从而允许直接研究 磁刺激的潜在机制。所有的微磁刺激器也将与MRI兼容， 允许使用功能磁共振成像进行大规模神经记录。这项技术将为神经科学研究服务- 研究外周和中枢神经系统(PNS)中神经元和神经网络的功能 和中枢神经系统)-增强或创造神经调节的新应用。所有这些应用程序都将允许我们 运用神经调节并研究微磁场脉冲如何用于刺激或阻断 动作电位(AP)流经神经系统，类似于经颅磁刺激 (TMS)产生兴奋和抑制。建议的µMS工具还将为社区提供一种方法 以期对TMS的作用机制有更深入的了解。

ABSTRACT Micromagnetic stimulation (µMS) has several advantages over electrical stimulation. First, µMS does not require charge-balanced stimulation waveforms as in electrical stimulation. In µMS, neither sinks nor sources are present when the time-varying magnetic field induces a current. Thus µMS does not suffer from charge buildup as can occur with electrical stimulation. Second, magnetic stimulation via µMS is capable of activating neurons with specific axonal orientations. Third, it is contactless, so biocompatible materials such as parylene will allow implantation with minimal or no reaction. Moreover, as the probes can be insulated entirely from the brain tissue, we show to significantly reduce the problem of excessive power deposition into the tissue during magnetic resonance imaging (MRI). In this application, we propose to design, fabricate, and test microcoil structures for next-generation Nervous System Stimulation: the micro coils arrays will be designed for cortical stimulation like ECoGs and deep brain stimulation. The array will be novel in the sense that it will allocate optical fibers to perform onsite optogenetic calcium channels recording in awake and behaving animals, thus allowing for direct study of the underlying mechanisms of magnetic stimulation. All the micromagnetic stimulators will also be MRI compatible, allowing for large scale neural recordings with fMRI. This technology will serve Neuroscience research— investigating the function of neurons and neural networks in the peripheral and central nervous system (PNS and CNS)—enhancing or creating new applications for neuromodulation. All of these applications will allow us to employ neuromodulation and study how micromagnetic field pulses can be used for stimulating or blocking the flow of Action Potentials (APs) through the nervous system, as similarly transcranial magnetic stimulation (TMS) produces excitation and inhibition. The proposed µMS tools will also provide the community with a way to reach a more in-depth understanding of the mechanisms of actions of TMS.