Study on Improving the Modulatory Effect of Rhythmic Oscillations by Transcranial Magneto-Acoustic Stimulation
Ruxin Tan, Ren Ma, Fangxuan Chu, Xiaoqing Zhou, Xin Wang, Tao Yin, Zhipeng Liu
IEEE Transactions on Neural Systems and Rehabilitation Engineering 2024 · 10.1109/tnsre.2024.3395641
Abstract
In hippocampus, synaptic plasticity and rhythmic oscillations reflect the cytological basis and the intermediate level of cognition, respectively. Transcranial ultrasound stimulation (TUS) has demonstrated the ability to elicit changes in neural response. However, the modulatory effect of TUS on synaptic plasticity and rhythmic oscillations was insufficient in the present studies, which may be attributed to the fact that TUS acts mainly through mechanical forces. To enhance the modulatory effect on synaptic plasticity and rhythmic oscillations, transcranial magneto-acoustic stimulation (TMAS) which induced a coupled electric field together with TUS's ultrasound field was applied. The modulatory effect of TMAS and TUS with a pulse repetition frequency of 100 Hz were compared. TMAS/TUS were performed on C57 mice for 7 days at two different ultrasound intensities (3 W/cm2 and 5 W/cm [Formula: see text]. Behavioral tests, long-term potential (LTP) and local field potentials in vivo were performed to evaluate TUS/TMAS modulatory effect on cognition, synaptic plasticity and rhythmic oscillations. Protein expression based on western blotting were used to investigate the under- lying mechanisms of these beneficial effects. At 5 W/cm2, TMAS-induced LTP were 113.4% compared to the sham group and 110.5% compared to TUS. Moreover, the relative power of high gamma oscillations (50-100Hz) in the TMAS group ( 1.060±0.155 %) was markedly higher than that in the TUS group ( 0.560±0.114 %) and sham group ( 0.570±0.088 %). TMAS significantly enhanced the synchronization of theta and gamma oscillations as well as theta-gamma cross-frequency coupling. Whereas, TUS did not show relative enhancements. TMAS provides enhanced effect for modulating the synaptic plasticity and rhythmic oscillations in hippocampus.
Abstract via europepmc.
Exposures
Exposure 1: Hippocampus, TUS and TMAS (0.3 T magnet) at 3 and 5 W/cm2
Target: hippocampus — “hippocampus”
Device: other named manufacturer · IOA-AC, China · FP-1M
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 1,000 | ✓✓✓ |
| Pulse duration (ms) | not reportedimplied by duty cycle ÷ PRF: 0.5 ms (not stated by the paper) | ⚑ |
| Pulse repetition frequency (Hz) | 100 | ✓✓✓ |
| Duty cycle (%) | 5 | ✓✓✓ |
| Sonication duration (s) | 300 | ✓✓✓ |
| 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 | |
| Pressure, domain unspecified (kPa) | 210, 270swept | ✓✓✓⚑ |
| Isppa, domain unspecified (W/cm²) | 3, 5swept | ✓✓✓⚑ |
100 Hz pulse repetition frequency and 5% duty cycle, 5 minutes of sonication per mouse, daily for 7 days.
Flags from extraction
exposures[0].unspecified_domain.isppa_w_cm2— Intensity stated only as 3 and 5 W/cm2; the type (spatial-peak pulse-average or other) and domain are not stated.exposures[0].unspecified_domain.pressure_kpa— 0.21 and 0.27 MPa are given in the Discussion as the ultrasound pressures for 3 and 5 W/cm2; domain not stated.sham_type— Sham group not described.exposures[0].timing.pulse_duration_ms— Pulse duration not stated in text.exposures[0].target— Target given as hippocampus in text; the dentate gyrus recording site is stated but the sonication target is shown only in Fig. 1(d).