Under the shadowless lamp, electrodes were accurately implanted into the epidural space at the lateral aspect of the teenager’s spinal cord. As microcurrent passed through the damaged nerves, waveforms of electromyographic signals flickered on the monitor.
This marked a breakthrough in the rehabilitation of M, an 11-year-old student M with a spinal cord injury. It also represented a significant achievement for Hainan University’s BCI integrated Circuit & Neural Engineering Team, born from their frontline clinical practice.
Focusing on Patients’ Needs, Overcoming Technological Hurdles
In 2021, Associate Professor Liang Fengyan from the School of Biomedical Engineering, Hainan University, joined the team. The team is dedicated to the research and development of BCI chips and devices, exploring applications of BCI and neural modulation technologies in fields such as the diagnosis and treatment of brain diseases, limb injuries rehabilitation, and artificial intelligence (AI). Their work is paving the way for advancements in brain science, brain disorders, and other neurological studies, with the goal of industrializing these outcomes to benefit a wide range of patients.
Patients with spinal cord injuries often face issues such as limb paralysis, sensory loss, and urinary and fecal dysfunction, severely affecting their quality of life. While traditional rehabilitation therapies help to a certain extent, they have limited effects on the recovery of neural function.
In recent years, epidural electrical stimulation (EES), as an emerging treatment method, has attracted increasing attention. By implanting electrodes into the epidural space of the spinal cord, EES delivers electrical stimulation to neural circuits to enhance the excitability of neural networks, thereby helping patients to restore motor and sensory functions.
Since the late 1990s, neural modulation has been used in the treatment of spinal cord injuries. Particularly since 2010, a Swiss team led by Gregoire has successively verified that this method has certain therapeutic effects on the rehabilitation of spinal cord injuries in rats, monkeys, and humans, confirming the feasibility of its clinical application.
Director Han Xiaodi from Beijing Tiantan Hospital in China has accumulated years of experience in this therapy and has performed numerous procedures using the emerging EES treatment for spinal cord injuries. “Due to the high cost of imported equipment and the incomplete development of domestic research, patients with spinal cord injuries often regard neural modulation technology as their ‘last attempt’,” said Liang Fengyan.
Having focused on exoskeleton robot research during his doctoral studies, he recognized the application prospects of BCI technology and began to explore the possibility of an “exoskeleton +” approach.
Hospital-University Collaboration, Innovative Treatment Approach
In March 2024, 11-year-old Hainan teenager Student M fell from the 7th floor, resulting in a spinal cord injury, classified as ASIA Grade A (complete paralysis). After six months of rehabilitation, he barely improved to Grade B and hit a bottleneck in his recovery.
The family sought medical help from various sources, and a message from Chief Physician Song Zhenhua of the Department of Rehabilitation Medicine at Haikou People’s Hospital ignited their hope: a new “spinal cord electrical stimulation + exoskeleton” therapy, jointly developed by Hainan University and Beijing Tiantan Hospital, was being launched for the first time in Hainan.
A three-party collaboration was quickly formed: the team of Director Han Xiaodi from Beijing Tiantan Hospital leading the surgical plan; the Rehabilitation Department of Haikou People’s Hospital formulating the rehabilitation strategy, and the Hainan University team providing technical support for neural modulation and quantitative tracking.
In November 2024, Student M underwent epidural electrode implantation surgery, becoming the first spinal cord injury patient in Hainan Province to receive spinal cord electrical stimulation therapy.
Electromyographic (EMG) signal artifacts generated by electrical stimulation often cause severe interference to the adjustment of stimulation parameters and sites, affecting the accuracy of electrode implantation. In response to clinical needs, the team developed an EMG adaptive filtering algorithm. This algorithm can accurately separate artifacts and restore real EMG signals, ensuring precise electrode implantation and providing a “X-ray vision” for parameter adjustment during and after surgery.
The team has proposed an advanced rehabilitation treatment plan of “neural modulation + robotic rehabilitation”. While using epidural electrical stimulation to promote muscle activation, the patient is also fitted with an exoskeleton device to provide physical and kinesthetic feedback and assist in motor training. This two-pronged approach achieves a “1+1>2” therapeutic effect.
The team has also utilized quantitative assessment systems such as wireless EMG and infrared motion capture to replace traditional relatively crude scales. This provides a scientific benchmark for clinical practice, helping doctors better understand the patient’s condition and adjust treatment plans timely. EMG signals, gait trajectories, joint angles, center of gravity changes... the data on the display screen show small yet consistent progress.
As of June 2025, Student M has recovered from ASIA Grade A to Grade D. The muscle strength, motor function, and sensation of both lower limbs have all improved, including a two-vertebrae drop in sensory level of his lower limbs, a markedly faster walking speed, and a more stable gait.
Student M will return to school this September. “The Hainan University team has given our family great comfort and support. We hope they can develop therapeutic devices more quickly to alleviate the suffering of a large number of patients,” said Student M’s family.
Dual-Path R&D: Opening the “Technological Tunnel” for BCI
“Independently developing implantable BCI-specific chips and deploying them in clinical settings requires navigating a mandatory five-year pathway of quality testing, ethical approval, and clinical trials,” noted the team. To achieve breakthroughs as soon as possible, they decide to adopt a “two-pronged approach.”
Professor Yin Ming, the team leader, has led the team to focus on the independent R&D of high-density neural signal acquisition chips and neural modulation chips, striving to break through core technological “chokepoint”. On the other hand, Liang Fengyan has focused on the clinical application of spinal cord electrical stimulation: he has advanced the accumulation of clinical data, developed corresponding algorithms, and explored exoskeleton-integrated treatment plans.
By working on two parallel tracks, the team has, through dual-path R&D, opened the critical “tunnel” that connects independent hardware R&D to clinical application for BCI technology.
The university has provided the team with excellent research facilities, including a non-human primate model animal research base and an MRI Imaging Center. This enables the team to conduct experiments simultaneously on animal models and in clinical settings, facilitating “interdisciplinary” convergence between biomedicine, electronic engineering and other fields.
The team has developed three types of core chips: the SX-R128S4 high-throughput neural signal acquisition and stimulation chip, the SX-S32 high-channel-count neural modulation chip, and the SX-WD60 low-power wireless transmission chip. These three core chips are world-class in key indicators such as neural signal acquisition accuracy, modulation degree of freedom, and wireless transmission efficiency, ending China’s long-standing reliance on imported chips in this field.
Meanwhile, the technical closed-loop of acquisition-regulation-transmission formed by the three covers the end-to-end requirements of BCIs, enabling China to achieve self-sufficiency in the entire BCI chip chain.
“Currently, the cost of spinal cord stimulation therapy remains a barrier,” said Liang Fengyan with a firm gaze. “We are joining hands with domestic enterprises to tackle key challenges, hoping to make the current treatment cost of 200,000 to 300,000 yuan a thing of the past.”
Reportedly, the neural signal acquisition and stimulation chips as well as neural modulation chips developed by the team have completed the transformation of scientific research achievements, which is expected to reduce the cost of current neural regulation devices. This will bring good news to patients with neurological diseases such as spinal cord injuries, Parkinson’s disease, and epilepsy.
“The team will cooperate with domestic top-tier teams to continue developing better-suited electrodes, advance the clinical testing of self-developed chips, achieve more precise regulation, and strive to transform the achievements of animal experiments into usable BCI devices for patients as soon as possible,” Liang Fengyan told the reporter.
From decoding neural signals to restoring the dignity of life, this research team rooted in Hainan has been continually making technological breakthroughs, exploring the broad possibilities of BCIs empowering healthcare, and conveying the warmth and sense of responsibility of scientific and technological workers.
With joint “excavation” on both the scientific research and clinical fronts, the technological “tunnel” will eventually break through. For patients, that will be a moment filled with hope.
Translated by Shi Buyue
Proofread by Zhao Yanchun
