基于磁声耦合效应的聚焦电刺激方法的初探

Approach for Focused Electric Stimulation based on the Magneto-acoustic Effect

神经电刺激是一种重要的治疗和脑科学研究手段,本研究基于磁声电耦合原理,提出用聚焦超声实现电介质样本聚焦电刺激,并开展了验证实验。我们使用聚焦超声换能器向置于静磁场中的导电样本打入超声,测量了沿不同方向样本两端产生的电信号,使用声场分析仪和磁声耦合电刺激系统分别测试了声场和电场在同一区域内的分布,并将二者归一化后进行对比。实验结果证明,在实验条件下,待刺激样本中会产生与声场、静磁场方向均正交的感应电场,且超声换能器的声场与感应电场的分布之间存在较高一致性,二者在测试平面中心线上的相关系数分别为0.930和0.997,初步证明了该方法的可行性。

Electrical nerve stimulation is an important technology for therapy and brain research. In this paper,a novel method that using focused ultrasound to induce the electrical stimulation was proposed based on the magneto- acoustic- electric effect. A series of refined experiments were carried out to validate the proposed method. In the experiment,a focused transducer was utilized to transmit ultrasound pulse into a conductive sample,effected by the static magnetic field,the electrical voltage signals induced in the sample were measured along the different directions. An acoustic field analyzer and the magneto- acoustic- electric stimulation system were used to measure the distribution of acoustic field and electrical field within the same area,respectively. Furthermore,the normalized results were compared with respect to the distribution difference of acoustic field and electric field. It shows that under the certain experimental conditions,the inducted electric field is simultaneously perpendicular to the direction of the static magnetic field as well as the acoustic field. The distributions of the induced electric field has a high consistency contrasted with the acoustic field of ultrasonic transducer,and the correlation coefficients in the center line of the test panel of which are 0. 930 and 0. 997,respectively. These results prove the feasibility of theproposed method.