Although transcranial magnetic stimulation (TMS) is widely used in neuromodulation, conventional TMS struggles to achieve both depth and focal specificity. Temporal interference TMS (TI-TMS) offers a promising approach to enhance stimulation depth while reducing the focal area; however, current research remains largely simulation-based, with limited studies on system implementation and experimental validation in rodent deep brain regions. To address this, we developed a TI-TMS system based on a realistic mouse head model using finite element simulation. Electrophysiological recordings of local field potentials (LFPs) in the ventral hippocampal (vHPC) formation were performed to evaluate changes in θ rhythm power spectral density (PSD) and θ-γ phase-amplitude coupling (PAC) following stimulation. The results demonstrated that TI-TMS enhanced θ rhythm power and strengthened θ-γ PAC, indicating effective modulation of deep brain regions. This study establishes a functional TI-TMS system capable of effectively stimulating deep vHPC, providing an experimental basis for its application in precise neuromodulation of subcortical brain areas.
In recent years, the ongoing development of transcranial electrical stimulation (TES) and transcranial magnetic stimulation (TMS) has demonstrated significant potential in the treatment and rehabilitation of various brain diseases. In particular, the combined application of TES and TMS has shown considerable clinical value due to their potential synergistic effects. This paper first systematically reviews the mechanisms underlying TES and TMS, highlighting their respective advantages and limitations. Subsequently, the potential mechanisms of transcranial electromagnetic combined stimulation are explored, with a particular focus on three combined stimulation protocols: Repetitive TMS (rTMS) with transcranial direct current stimulation (tDCS), rTMS with transcranial alternating current stimulation (tACS), and theta burst TMS (TBS) with tACS, as well as their clinical applications in brain diseases. Finally, the paper analyzes the key challenges in transcranial electromagnetic combined stimulation research and outlines its future development directions. The aim of this paper is to provide a reference for the optimization and application of transcranial electromagnetic combined stimulation schemes in the treatment and rehabilitation of brain diseases.