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Improved Anatomical Specificity of Non-invasive Neuro-stimulation by High Frequency (5 MHz) Ultrasound.

Li GF, Zhao HX, Zhou H, Yan F, Wang JY, Xu CX, Wang CZ, Niu LL, Meng L, Wu S, Zhang HL, Qiu WB, Zheng HR - Sci Rep (2016)

Bottom Line: Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects.Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation.It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.

ABSTRACT
Low frequency ultrasound (<1 MHz) has been demonstrated to be a promising approach for non-invasive neuro-stimulation. However, the focal width is limited to be half centimeter scale. Minimizing the stimulation region with higher frequency ultrasound will provide a great opportunity to expand its application. This study first time examines the feasibility of using high frequency (5 MHz) ultrasound to achieve neuro-stimulation in brain, and verifies the anatomical specificity of neuro-stimulation in vivo. 1 MHz and 5 MHz ultrasound stimulation were evaluated in the same group of mice. Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects. Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation. The equivalent diameter (ED) of the stimulation region with 5 MHz ultrasound (0.29 ± 0.08 mm) is significantly smaller than that with 1 MHz (0.83 ± 0.11 mm). The response latency of 5 MHz ultrasound (45 ± 31 ms) is also shorter than that of 1 MHz ultrasound (208 ± 111 ms). Consequently, high frequency (5 MHz) ultrasound can successfully activate the brain circuits in mice. It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

No MeSH data available.


Related in: MedlinePlus

Illustration of motion responses evoked by 5 MHz ultrasound stimulus.(a) EMG signal (upper waveform) acquired from a mouse tail shows the motion responses evoked by ultrasound stimuli. The bottom waveform is a synchronous signal indicating the stimuli phases. The red bars represent some active response periods, while the white bars represent no stimuli periods. (b) Three curves (n = 20 stimuli) represent trends of the peak EMG amplitudes evoked by 5 MHz ultrasound varying with different acoustic intensities at three different time frames, i.e. 50 min, 80 min, and 110 min after the first anesthesia injection, respectively. The error bars show the standard deviations.
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f3: Illustration of motion responses evoked by 5 MHz ultrasound stimulus.(a) EMG signal (upper waveform) acquired from a mouse tail shows the motion responses evoked by ultrasound stimuli. The bottom waveform is a synchronous signal indicating the stimuli phases. The red bars represent some active response periods, while the white bars represent no stimuli periods. (b) Three curves (n = 20 stimuli) represent trends of the peak EMG amplitudes evoked by 5 MHz ultrasound varying with different acoustic intensities at three different time frames, i.e. 50 min, 80 min, and 110 min after the first anesthesia injection, respectively. The error bars show the standard deviations.

Mentions: According to the experiments, 5 MHz ultrasound can successfully activate the brain circuits in mice to induce tail flicks. Figure 3a shows EMG signals from the tail evoked by 5 MHz ultrasound with Ispta = 210 mW/cm2, and the synchronous signals which were used for indicating the stimuli phases. Video can be found from Supplementary material (Supplementary Video S1). Figure 3b shows the peak EMG amplitudes varied with different acoustic intensities of 5 MHz ultrasound at three different time frames, i.e. 50 min, 80 min, and 110 min after the first anesthesia injection. These three curves have a similar pattern that is the peak EMG amplitude increases as the acoustic intensity goes up. The stimulation is stable and can be maintained in long time (>60 minutes) with high frequency ultrasound. All of the error bars stand for the standard deviations.


Improved Anatomical Specificity of Non-invasive Neuro-stimulation by High Frequency (5 MHz) Ultrasound.

Li GF, Zhao HX, Zhou H, Yan F, Wang JY, Xu CX, Wang CZ, Niu LL, Meng L, Wu S, Zhang HL, Qiu WB, Zheng HR - Sci Rep (2016)

Illustration of motion responses evoked by 5 MHz ultrasound stimulus.(a) EMG signal (upper waveform) acquired from a mouse tail shows the motion responses evoked by ultrasound stimuli. The bottom waveform is a synchronous signal indicating the stimuli phases. The red bars represent some active response periods, while the white bars represent no stimuli periods. (b) Three curves (n = 20 stimuli) represent trends of the peak EMG amplitudes evoked by 5 MHz ultrasound varying with different acoustic intensities at three different time frames, i.e. 50 min, 80 min, and 110 min after the first anesthesia injection, respectively. The error bars show the standard deviations.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4837374&req=5

f3: Illustration of motion responses evoked by 5 MHz ultrasound stimulus.(a) EMG signal (upper waveform) acquired from a mouse tail shows the motion responses evoked by ultrasound stimuli. The bottom waveform is a synchronous signal indicating the stimuli phases. The red bars represent some active response periods, while the white bars represent no stimuli periods. (b) Three curves (n = 20 stimuli) represent trends of the peak EMG amplitudes evoked by 5 MHz ultrasound varying with different acoustic intensities at three different time frames, i.e. 50 min, 80 min, and 110 min after the first anesthesia injection, respectively. The error bars show the standard deviations.
Mentions: According to the experiments, 5 MHz ultrasound can successfully activate the brain circuits in mice to induce tail flicks. Figure 3a shows EMG signals from the tail evoked by 5 MHz ultrasound with Ispta = 210 mW/cm2, and the synchronous signals which were used for indicating the stimuli phases. Video can be found from Supplementary material (Supplementary Video S1). Figure 3b shows the peak EMG amplitudes varied with different acoustic intensities of 5 MHz ultrasound at three different time frames, i.e. 50 min, 80 min, and 110 min after the first anesthesia injection. These three curves have a similar pattern that is the peak EMG amplitude increases as the acoustic intensity goes up. The stimulation is stable and can be maintained in long time (>60 minutes) with high frequency ultrasound. All of the error bars stand for the standard deviations.

Bottom Line: Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects.Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation.It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.

ABSTRACT
Low frequency ultrasound (<1 MHz) has been demonstrated to be a promising approach for non-invasive neuro-stimulation. However, the focal width is limited to be half centimeter scale. Minimizing the stimulation region with higher frequency ultrasound will provide a great opportunity to expand its application. This study first time examines the feasibility of using high frequency (5 MHz) ultrasound to achieve neuro-stimulation in brain, and verifies the anatomical specificity of neuro-stimulation in vivo. 1 MHz and 5 MHz ultrasound stimulation were evaluated in the same group of mice. Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects. Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation. The equivalent diameter (ED) of the stimulation region with 5 MHz ultrasound (0.29 ± 0.08 mm) is significantly smaller than that with 1 MHz (0.83 ± 0.11 mm). The response latency of 5 MHz ultrasound (45 ± 31 ms) is also shorter than that of 1 MHz ultrasound (208 ± 111 ms). Consequently, high frequency (5 MHz) ultrasound can successfully activate the brain circuits in mice. It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

No MeSH data available.


Related in: MedlinePlus