Research on Focusing Effect of Electromagnetic Stimulation Based on Liquid Metal

Electromagnetic stimulation is pivotal in diagnosing and treating neurological and psychiatric disorders. However, achieving effective stimulation hinges significantly on the precision of the stimulation focus. Presently, the focal area of electromagnetic stimulation remains at the centimeter scale, which poses substantial challenges when targeting fine brain regions. To address this limitation, this study introduces a novel method that leverages liquid metal to enhance the focusing ability of electromagnetic stimulation. By utilizing liquid metal to concentrate the induced electric field generated by electromagnetic excitation, we can achieve highly focused stimulation. This innovative approach has been preliminarily validated through both finite element simulations and experimental studies, demonstrating the liquid metal's capacity to significantly enhance the focusing of the induced electric field. The results indicate that liquid metal can reduce the focal size of electromagnetic stimulation to the millimeter scale, with peak induced field strength achieving up to approximately 300% enhancement, realizing a millimeter-scale focal area. Furthermore, it was explored that controlling the spatial distribution of liquid metal could achieve even higher electric field intensity. A measurement platform was constructed to validate the simulation results in gel models, with additional verification conducted through simulations in a realistic human head model based on MRI data. In summary, the liquid metal-based focusing stimulation method proposed in this study represents a significant advancement in improving the precision of electromagnetic stimulation. This innovation holds great promise for advancing the field of precise electromagnetic stimulation, offering a powerful new tool for both research and clinical applications.