Transcranial ultrasonic stimulation (TUS) is an innovative and non-invasive method of brain stimulation that offers a higher spatial resolution than traditional electrical and magnetic stimulation techniques. Additionally, TUS has the unique ability to target deep brain structures. Early studies in humans have shown that TUS can evoke neural activity as well as modulate activity elicited by other stimuli. However, the protocols used in these studies may be audible due to the sharp onset and offset of ultrasound energy, which raises concerns about the potential for an auditory confound to the observed effects.
经颅超声刺激 (TUS) 是一种创新的非侵入性脑刺激方法，与传统的电和磁刺激技术相比，它具有更高的空间分辨率。此外，TUS 具有针对深部脑结构的独特能力。对人类的早期研究表明，TUS 可以唤起神经活动以及调节由其他刺激引起的活动。然而，由于超声能量的急剧启动和偏移，这些研究中使用的协议可能会被听到，这引起了人们对观察到的效果可能存在听觉混淆的担忧。

To further investigate the effects of TUS, a group of researchers at Johannes Gutenberg University Medical Center and University College London (UCL) used a less audible, ramped protocol to determine if they could either evoke or modulate activity in the primary visual cortex (V1). In their study, 14 healthy participants (4 female, 31 ± 4.3 years) were included, and the project was approved by the UCL research ethics committee.
为了进一步研究 TUS 的影响，约翰内斯古腾堡大学医学中心和伦敦大学学院 (UCL) 的一组研究人员使用了一种声音较小的斜坡方案来确定他们是否可以唤起或调节初级视觉皮层 (V1) 的活动。在他们的研究中，包括 14 名健康参与者（4 名女性，31 ± 4.3 岁），该项目获得了 UCL 研究伦理委员会的批准。

The TUS was delivered using a 2-element spherically focusing annular array transducer (H115-2AA, ) with a nominal outer aperture diameter and radius of curvature of 64mm. The transducer was driven at 270 kHz by a 2-channel TPO (Sonic Concepts) with the output power and element phase adjusted to give a focal pressure in water of 700 kPa (spatial peak pulse average intensity without ramping of 16 W/cm2) and a focal distance of 43 mm. The measured -3 dB focal size in water was 5 mm (lateral) by 30 mm (axial). Ramped pulses (1 ms Tukey ramp, 3.25 ms total pulse duration) were applied at a pulse repetition frequency (PRF)
TUS 使用标称外孔径和曲率半径为 64 毫米的 NeuroFUS PRO 2 元件球面聚焦环形阵列换能器（H115-2AA，Sonic Concepts）交付。换能器由 2 通道 TPO（Sonic Concepts）以 270 kHz 驱动，输出功率和元件相位调整为在水中提供 700 kPa 的焦点压力（空间峰值脉冲平均强度，没有 16 W/cm2 的斜坡）和焦距为 43 毫米。在水中测得的 -3 dB 焦距为 5 毫米（横向）乘以 30 毫米（轴向）。以脉冲重复频率 (PRF) 施加斜坡脉冲（1 ms Tukey 斜坡，3.25 ms 总脉冲持续时间）

Key points 关键点

• In this study, a less audible ramped protocol was used to examine whether TUS alone can evoke neural activity in the primary visual cortex (V1) and whether it can modulate visual evoked potentials (VEPs) in response to a pattern-reversal checkerboard stimulus
  在这项研究中，使用一种声音较小的斜坡方案来检查单独的 TUS 是否可以唤起初级视觉皮层 (V1) 中的神经活动，以及它是否可以调节视觉诱发电位 (VEP) 以响应模式反转棋盘刺激

• 14 healthy participants were included in the study and EEG was recorded from 16 channels
  研究包括 14 名健康参与者，并从 16 个通道记录脑电图

• The results showed that TUS alone did not evoke any potentials and there was no significant difference between real and sham TUS conditions, but TUS did modulate the N75 component of the VEP, which likely originates in V1
  结果表明单独的 TUS 不会引起任何电位，真实和假 TUS 条件之间没有显着差异，但 TUS 确实调节了 VEP 的 N75 成分，这可能起源于 V1

• The study suggests that TUS can be a useful tool for studying the physiological basis of visual perception and for modulating neural activity in basic science and clinical applications, but replication studies are needed to draw definitive conclusions.
  该研究表明，TUS 可以成为研究视觉感知的生理基础以及调节基础科学和临床应用中的神经活动的有用工具，但需要重复研究才能得出明确的结论。

Reference Paper 参考论文

Nandi, T. et al. (2023) “Ramped V1 transcranial ultrasonic stimulation modulates but does not evoke visual evoked potentials,” Brain Stimulation, 16(2), pp. 553–555. Available at: .
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