During his postdoctoral training at MIT, Prof. Po-Han Chiang advanced wireless neural control technologies—laying the groundwork for next-generation, fully wireless brain stimulation.

“That was the world’s first research to use magnetic fields to generate thermal energy in magnetic nanoparticles, thereby stimulating neurons. Ever since reading that paper, I have had this dream— one day, I’ll achieve it using a completely wireless method, because it is so cool!” This dream propelled Po-Han Chiang to pursue postdoctoral research at MIT in 2016, where he studied various wireless neural control technologies that harness magnetic fields to generate thermal, mechanical, and electrical energy.

Since neurons communicate through electrical signals, academia has been devoted to exploring innovations in magnetoelectric stimulation technology in recent years. However, traditional magnetoelectric stimulation techniques, aside from DBS, such as the clinically widely adopted “transcranial magnetic stimulation”, require a strong magnetic field of approximately 1.5 Tesla. The drawback is that the stimulation area is too large and limited to the brain’s surface layer. Although another approach, “magnetostriction using nanomagnetic particles,”can stimulate deeper brain regions, due to the extremely minute expansion and contraction of these nanoparticles, it relies on high-frequency magnetic fields delivering sustained stimulation over extended periods (1 to several seconds) to accumulate sufficient energy and induce neurons to respond.

To overcome the shortcomings of existing technologies, Po-Han Chiang dedicated himself to developing MagTIES technology after returning to Taiwan to teach. During the in vitro cultivation of neurons and validation phase, the team first attached biocompatible and non-toxic piezoelectric nanoparticles of barium titanate to the neuronal membrane. They then injected a hexagonal magnetic nanodisc with a diameter of approximately 250 nanometers and a thickness of about 35 nanometers. Since the surfaces of both materials were coated with polymeric polymers, they subsequently bonded automatically through biological adhesion. When an alternating magnetic field was applied externally, it drove the magnetic nanodisc to vibrate, generating torque that stimulated the underlying piezoelectric nanoparticles to produce an electric field. This, in turn, excited the neurons to generate action potentials.
 

To verify reaction speed, the team employed a membrane potential imaging system and high-speed cameras to directly observe changes in neuronal membrane potential. Results showed that MagTIES captures neural action potentials in only about 10 milliseconds, making it 100 to 1,000 times faster than other previous magnetoelectric stimulation technologies.

Precision Control for Remarkable Results

Following breakthrough progress in in vitro cell experiments, the next phase involves tackling more complex in vivo experiments in mice. First, the research team surprisingly discovered that each magnetic field stimulation induced brain oscillations in the mouse brain at twice the frequency of the applied magnetic field. Po-Han Chiang explained:“Each cycle of the alternating magnetic field involves two directional reversals, effectively delivering two stimuli to the neurons. This dual stimulation generates brain waves at twice the frequency of the magnetic field.”This result demonstrates the team’s comprehensive ability to modulate brain oscillations, which are achievements previously unattainable with conventional wireless Deep Brain Stimulation technologies.

Fiber photometry shows that MagTIES stimulation in live mice induces synchronized brain oscillations at precisely twice the applied magnetic field frequency, reflecting millisecond-scale neural activation with each field reversal.

The research further demonstrates that MagTIES not only stimulates deep brain regions like the amygdala but can also precisely modulate brain waves to specific frequency bands based on magnetic field frequencies. For instance, it can induce beta waves associated with emotions and concentration. Po-Han Chiang analyzed that many fear-related disorders, such as panic disorder or post-traumatic stress disorder, are associated with amygdala dysfunction. By precisely modulating specific frequency brain waves linked to emotions using MagTIES technology, it is expected to alleviate symptoms promptly during patient episodes in the future.

Currently, nanomaterials still require ‘minimally invasive’ intracranial injection, but without leaving hardware implants like electrodes or optical fibers, significantly reducing the invasiveness of deep brain stimulation. In the next phase, we hope to collaborate with specialized laboratories to investigate achieving ‘non-invasive’ delivery of nanomaterials,” Po-Han Chiang states. Conducting safety validation through large animal studies and observing the metabolic time of nanomaterials within the body are essential hurdles to overcome before advancing to human applications.

Open-source Sharing to Expand Applications

MagTIES offers significant advantages that lower the barrier to use: it utilizes a low magnetic field strength, operates at a frequency of only about 10Hz, features a simple system setup and operation, employs inexpensive and readily available materials, and requires no complex synthesis techniques. In fact, all coil designs, circuit designs, analysis software, and user interfaces were co-developed by Po-Han Chiang and his graduate students.

To promote MagTIES technology, the team led by Po-Han Chiang has also developed a low-cost, open-source magnetoelectric stimulation system. Not only does it keep the setup cost under NTD$100,000, but it also features a user-friendly graphical interface to enable basic research or clinical research teams without an electrical engineering and information background to easily operate and utilize the system.“The next priority is researching how to treat various diseases. We want to explore every condition that can be addressed with DBS therapy,”Po-Han Chiang adds.

He emphasized that the current research remains in the proof-of-concept phase, with a long road ahead before reaching clinical treatment. “DBS was successfully demonstrated in experiments as early as the 1950s, yet it wasn’t applied to humans until around the year 2000.” Po-Han Chiang maintains an optimistic yet rigorous stance toward the widespread adoption of MagTIES, recognizing that every technological leap requires time to mature.

“If needed, we can provide design schematics, circuit boards, software, and even nanomaterials for all systems.” Po-Han Chiang believes that promoting this technology is currently more important than commercialization. Only through broader adoption and user feedback can issues be continuously refined, proving the technology’s feasibility and value across diverse applications.

MagTIES is built as a low-cost, open-source system—with accessible hardware, software, and nanomaterials—designed to lower barriers, accelerate global research, and expand future clinical applications.