Development of a Novel TMS Device with Controllable Pulse Shape (cTMS)

描述（由申请人提供）：该提案响应 PA-06-278（神经技术研究、开发和增强），该提案呼吁“显着增强现有技术……在基础或临床研究中研究大脑或行为”。我们提出了一种新颖的设备设计，通过引入对脉冲形状的连续用户控制，显着扩展了经颅磁刺激（TMS）作为具有治疗潜力的脑功能无创探针的功能。 TMS 通过短暂的磁脉冲感应脑电流来调节大脑活动。 TMS 已证明具有显着的抗抑郁作用，但与最佳临床结果相关的剂量参数尚未确定和优化。尽管众所周知，神经反应对刺激脉冲的形状高度敏感，但现有的 TMS 设备只能对刺激波形进行有限的控制。传统的 TMS 设备会产生正弦指数脑电流脉冲，而研究表明矩形脉冲会更有效。此外，临床应用中使用的高频 TMS 设备会产生双向电流，而研究表明单极电流会更有效。最后，众所周知，脉冲宽度会影响刺激效率，但该参数无法在传统 TMS 设备中控制。我们的目标是设计、模拟、实施、台架测试和表征一种具有可控脉冲形状 (cTMS) 的新型 TMS 设备，能够感应具有可控脉冲宽度和形状的近似矩形、主要是单极的脑电流。 cTMS 设备使用新推出的高功率半导体设备，在正电容器组和负电容器组之间切换刺激线圈。我们提出的仿真支持 cTMS 系统的可行性以及矩形脉冲效率的提高。第一个具有可控宽度和方向性的矩形脉冲形状的 TMS 设备将有助于优化 TMS 作为大脑功能的探针，并作为与人脑生理学更紧密匹配的潜在治疗干预措施。 TMS 有望用于研究和治疗抑郁症和精神分裂症等精神和神经疾病，但其有效性在一定程度上受到设备限制的限制。所提出的电子设备扩展了该技术的功能，有助于实现其巨大的临床治疗潜力。

DESCRIPTION (provided by applicant): This proposal responds to PA-06-278 (Neurotechnology Research, Development, and Enhancement) which calls for "significant enhancement of existing technologies ... to study the brain or behavior in basic or clinical research." We present a novel device design that substantially expands the functionality of transcranial magnetic stimulation (TMS) as a noninvasive probe of brain function with therapeutic potential by introducing continuous user-control of pulse shape. TMS modulates brain activity through the induction of cerebral currents by brief magnetic pulses. TMS has demonstrated significant antidepressant effects, but the dosing parameters associated with the best clinical outcome have yet to be identified and optimized. Although neural response is known to be highly sensitive to the shape of the stimulating pulse, existing TMS devices allow only limited control over stimulus waveform. Conventional TMS devices induce sinusoidal-exponential cerebral current pulses, while studies suggest that rectangular pulses will be more efficient. Further, high-frequency TMS devices used in clinical applications induce bidirectional current flow, while research suggests that unipolar currents would be more effective. Finally, pulse width is known to influence the efficiency of stimulation, but this parameter cannot be controlled in conventional TMS devices. We aim to design, simulate, implement, bench test and characterize a novel TMS device with controllable pulse shape (cTMS), capable of inducing approximately rectangular, predominately unipolar cerebral currents with controllable pulse width and shape. The cTMS device switches the stimulating coil between a positive and a negative capacitor bank, using newly available high-power semiconductor devices. We present simulations supporting the feasibility of the cTMS system, and the increased efficiency of rectangular pulses. The first TMS device with rectangular pulse shape with controllable width and directionality will facilitate optimization of TMS as a probe of brain function and as a potential therapeutic intervention more closely matched to the physiology of the human brain. TMS holds promise for studying and treating psychiatric and neurological illnesses such as depression and schizophrenia, but its effectiveness has been constrained in part by device limitations. The proposed electronic device expands the functionality of this technique, helping to bring its substantial clinical therapeutic potential to fruition.