Gibson Benjamin C, Sanguinetti Joseph L, Badran Bashar W, Yu Alfred B, Klein Evan P, Abbott Christopher C, Hansberger Jeffrey T, Clark Vincent P
Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, United States.
U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, United States.
Front Neurol. 2018 Nov 28;9:1007. doi: 10.3389/fneur.2018.01007. eCollection 2018.
Transcranial Ultrasound Stimulation (tUS) is an emerging technique that uses ultrasonic waves to noninvasively modulate brain activity. As with other forms of non-invasive brain stimulation (NIBS), tUS may be useful for altering cortical excitability and neuroplasticity for a variety of research and clinical applications. The effects of tUS on cortical excitability are still unclear, and further complications arise from the wide parameter space offered by various types of devices, transducer arrangements, and stimulation protocols. Diagnostic ultrasound imaging devices are safe, commonly available systems that may be useful for tUS. However, the feasibility of modifying brain activity with diagnostic tUS is currently unknown. We aimed to examine the effects of a commercial diagnostic tUS device using an imaging protocol on cortical excitability. We hypothesized that imaging tUS applied to motor cortex could induce changes in cortical excitability as measured using a transcranial magnetic stimulation (TMS) motor evoked potential (MEP) paradigm. Forty-three subjects were assigned to receive either verum ( = 21) or sham ( = 22) diagnostic tUS in a single-blind design. Baseline motor cortex excitability was measured using MEPs elicited by TMS. Diagnostic tUS was subsequently administered to the same cortical area for 2 min, immediately followed by repeated post-stimulation MEPs recorded up to 16 min post-stimulation. Verum tUS increased excitability in the motor cortex (from baseline) by 33.7% immediately following tUS ( = 0.009), and 32.4% ( = 0.047) 6 min later, with excitability no longer significantly different from baseline by 11 min post-stimulation. By contrast, subjects receiving sham tUS showed no significant changes in MEP amplitude. These findings demonstrate that tUS delivered via a commercially available diagnostic imaging ultrasound system transiently increases excitability in the motor cortex as measured by MEPs. Diagnostic tUS devices are currently used for internal imaging in many health care settings, and the present results suggest that these same devices may also offer a promising tool for noninvasively modulating activity in the central nervous system. Further studies exploring the use of diagnostic imaging devices for neuromodulation are warranted.
经颅超声刺激（tUS）是一种新兴技术，它利用超声波来无创地调节大脑活动。与其他形式的无创脑刺激（NIBS）一样，tUS可能有助于改变皮质兴奋性和神经可塑性，以用于各种研究和临床应用。tUS对皮质兴奋性的影响仍不明确，并且由于各种类型的设备、换能器布置和刺激方案所提供的广泛参数空间，还会引发更多复杂问题。诊断性超声成像设备是安全且普遍可用的系统，可能对tUS有用。然而，目前尚不清楚使用诊断性tUS改变大脑活动的可行性。我们旨在研究使用成像方案的商用诊断性tUS设备对皮质兴奋性的影响。我们假设应用于运动皮质的成像tUS可诱导皮质兴奋性发生变化，这可通过经颅磁刺激（TMS）运动诱发电位（MEP）范式进行测量。43名受试者被分配接受真刺激（n = 21）或假刺激（n = 22）诊断性tUS，采用单盲设计。使用TMS诱发的MEP测量基线运动皮质兴奋性。随后对同一皮质区域进行2分钟的诊断性tUS，紧接着在刺激后长达16分钟记录重复的刺激后MEP。真刺激tUS在tUS后立即使运动皮质的兴奋性（相对于基线）增加了33.7%（p = 0.009），6分钟后增加了32.4%（p = 0.047），刺激后11分钟兴奋性与基线不再有显著差异。相比之下，接受假刺激tUS的受试者MEP振幅没有显著变化。这些发现表明，通过商用诊断性成像超声系统进行的tUS可使运动皮质的兴奋性短暂增加，这可通过MEP进行测量。诊断性tUS设备目前在许多医疗保健环境中用于内部成像，目前的结果表明，这些相同的设备也可能为无创调节中枢神经系统活动提供一种有前景的工具。有必要进一步开展研究，探索将诊断性成像设备用于神经调节。
