Low-intensity transcranial ultrasound stimulation facilitates hand motor function and cortical excitability: A crossover, randomized, double blind study
Meng-Fei Zhang, Wei-Zhou Chen, Fub-Biao Huang, Zhi-Yong Peng, Ying-Chan Quan, Zhi-Ming Tang
Frontiers in Neurology 2022 · 10.3389/fneur.2022.926027
Abstract
Objective Transcranial ultrasound stimulation (TUS) is a new form of non-invasive brain stimulation. Low-intensity TUS is considered highly safe. We aimed to investigate the effect of low-intensity TUS on hand reaction responses and cortical excitability in healthy adults. Methods This study used a crossover, randomized, and double-blind design. A total of 20 healthy participants were recruited for the study. All the participants received TUS and sham stimulation on separate days in random order. The finger tapping test (tapping score by using a tablet) and motor evoked potential (MEP) were assessed before and after stimulation, and discomfort levels were assessed using a visual analog scale (VAS) score. Results No significant differences in tapping score or MEP amplitude between the two experimental conditions were registered before stimulation. After stimulation, tapping scores were increased regardless of the specific treatment, and the real stimulation condition receiving TUS (90.4 ± 11.0 points) outperformed the sham stimulation condition (86.1 ± 8.4 points) ( p = 0.002). The MEP latency of real TUS (21.85 ± 1.33 ms) was shorter than that of sham TUS (22.42 ± 1.43 ms) ( p p = 0.005). There was no significant difference in the discomfort score between the two conditions ( p = 0.163). Conclusion Transcranial ultrasound stimulation (TUS) can decrease the hand reaction response time and latency of the MEP, enhance the excitability of the motor cortex, and improve hand motor function in healthy individuals without obvious discomfort.
Abstract via europepmc.
Exposures
Exposure 1: non-focused low-intensity TUS over the TMS motor hotspot
Target: primary motor cortex — “hotspot determined by TMS”
Device: other named manufacturer · Beijing Ruao Medical Technology Co., LTD. · UE860A ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 800 | ✓✓✓ |
| Pulse duration (ms) | 1,000 | ✓✓✓ |
| Pulse repetition frequency (Hz) | not reported | |
| Duty cycle (%) | not reported | |
| Sonication duration (s) | 600 | ✓✓✓⚑ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | not reported | |
| In-situ pressure (kPa) | not reported | |
| In-situ Isppa (W/cm²) | not reported | |
| In-situ Ispta (W/cm²) | not reported |
Single 10 min session of 1 s stimulation and 2 s rest (on-off ratio 1:2) at 1.2 W/cm2 and 0.8 MHz; probe diameter 20 mm; non-focused ultrasound.
Flags from extraction
exposures[0].unspecified_domain.ispta_w_cm2— The paper gives 'a power of 1.2 W/cm2' without saying whether it is Isppa, Ispta, a device setting or a measurement, or in which medium; not entered in any intensity field.exposures[0].timing.sonication_duration_s— 1 s on / 2 s off over 10 min; recorded the 1 s on-period. Duty cycle, PRF and pulse duration within the 1 s are not stated (1:2 is an on-off ratio of the 1 s/2 s cycle).n_sessions_per_subject— Counts the real and the sham session; each participant received one TUS session.auditory_control— Paper is silent on auditory confounds; sham probe was reversed with the instrument still on.