Multi-Scale Coupling Between LFP and EMG in Mice by Low-Intensity Pulsed Ultrasound Stimulation With Different Number of Tone-Burst
Ziqiang Jin, Xiaoling Chen, Zechuan Du, Yi Yuan, Xiaoli Li, Ping Xie
IEEE Transactions on Neural Systems and Rehabilitation Engineering 2025, 33, 1118-1125 · 10.1109/tnsre.2024.3492158
Abstract
Low-intensity pulsed ultrasound stimulation (LIPUS) as a non-invasive, high-spatial resolution and high penetration depth brain modulation technology has been used for modulating neuromuscular function. However, the modulation of neural electrical signal changes in the neuromuscular system by LIPUS remains to be explored. In this study, we stimulated the mouse brain motor cortex by LIPUS with different number of tone burst (NTB) and recorded the local field potential (LFP) signals of the target region and electromyography (EMG) of tail muscle. Multi-Scale Transfer Entropy (MSTE) analysis method was used to explore the multi-scale synchronization characteristics and functional cortico-muscular coupling(FCMC) strength changes of mice LFP-EMG before and after LIPUS under different NTBs. The results show that the MSTE of LFP-EMG before and after LIPUS stimulation was higher than that of EMG-LFP. After adding multi-scale, MSTE has a significant relationship with time scales. When NTB =200, the scale of extremum is the largest. There was a fitting intersection between LFP-EMG and EMG-LFP scale 7-21 before and after stimulation. After scale averaging, the LFP-EMG after stimulation was lower than that before stimulation, and the EMG-LFP after stimulation was higher than that before stimulation. Conclusion: There is a significant correlation between NTB and time scale before and after LIPUS, as well as upward and downward. Consequently, This study used FCMC methods to study different NTBs and multi-scale relationships, provides new variables from LIPUS parameters and analysis, and provides new reference for clinical applications of LIPUS.
Abstract via europepmc.
Exposures
Exposure 1: LIPUS of tail motor cortex with varying number of tone-bursts (NTB)
Target: motor cortex — “motor cortex, tail region”
Device: not reported
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | not reported | ⚑ |
| Pulse duration (ms) | not reported | ⚑ |
| Pulse repetition frequency (Hz) | 1,000 | ✓✓✓ |
| Duty cycle (%) | not reported | ⚑ |
| Sonication duration (s) | 3.6 | ✓✓✓ |
| 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 | |
| Isppa, domain unspecified (W/cm²) | 1.1 | ✓✓✓ |
In this paper, the parameter setting is Isppa = 1.1 W/cm2, SD = 3.6s, PRF = 1 kHz, FF = 50%, DC = 250, NTB = 100,150,200,250,300. A collimator, attached to the flat ultrasound transducer, was precisely targeted at the motor cortex located within the tail region of the mice, with a 60-degree angle between the LIPUS application and the microelectrode placement. LFP and EMG were recorded before and after LIPUS for each of the five NTB conditions, with 30 trials collected per group.
Flags from extraction
exposures[0].fundamental_frequency_khz— Text states 'FF = 50%, DC = 250' -- a percentage attached to fundamental frequency (FF) and an out-of-range value (250) attached to duty cycle (DC), which is very likely a label/value swap or extraction error in the source (DC is typically a percentage such as 50%, and FF a frequency such as 250 kHz), but the correct pairing cannot be determined with confidence, so both fields are left not_reported.exposures[0].timing.duty_cycle_pct— Same source inconsistency as fundamental_frequency_khz: 'FF = 50%, DC = 250' appears to have swapped labels/values; left not_reported rather than guessed.exposures[0].timing.pulse_duration_ms— Not stated; NTB (number of tone-bursts) is the paper's manipulated timing-related variable but does not map to pulse duration, PRF, duty cycle or sonication duration as defined by the schema, so it is only described in protocol_description.n_sessions_per_subject— Not stated whether the five NTB conditions were tested in one acute session or across multiple sessions per animal.