Figure 1: Scientists test brain-controlled external limbs (hands) rehabilitation robot. Figure 2: Researchers test brain-computer interface neuromuscular electrical stimulation of lower limb exoskeleton rehabilitation training robot.

Brain-computer interface team experiment site. All the above pictures are provided by Tianjin University

In "The Matrix", the protagonist connects to the matrix system through a brain-computer interface, shuttles through the real and virtual world; in "Ghost in the Shell", the brain-computer interface becomes an important connection bridge between humans and machines... These science fiction scenarios involve a cutting-edge technology - brain-computer interface.

Brain-computer interfaces are no longer just science fiction. The development of artificial intelligence, flexible materials, biosensors and other technologies has promoted the practicalization of brain-computer interface technology.

Among the scientific events worth paying attention to in 2025 listed on the British magazine Nature website, brain-computer interfaces are among them. At the beginning of the new year of 2025, at Huashan Hospital Affiliated to Fudan University, a female patient was thinking of "Happy New Year" in her mind. Her mind was successfully decoded by the computer and issued instructions, and she manipulated the robot to make a heart-to-heart move.

This issue of "Looking at the Frontier" approaches the latest progress in brain-computer interfaces, understands its scientific principles and implementation paths, and explores how it will affect the present and future of mankind.

--editor

Brain-computer interface is called the "information highway" for the human brain to communicate with the outside world. It is a cutting-edge technology of the new generation of human-computer interaction and human-computer hybrid intelligence, and is expected to become a future industry that promotes economic and social development and improves people's livelihood and health.

Typing thoughts, speaking thoughts, and the brain-computer interface comes from science fiction

The brain-computer interface is an information connection path created between humans and external devices, realizing the so-called "thinking" control. Specifically, when the brain is active, neurons will discharge brain waves, and the brain-computer interface directly reads the brain's intentions by identifying brain wave features to achieve interaction between people and machines or external environments.

In recent years, with the development of biomedical engineering, neuroengineering and rehabilitation engineering, cognitive neuroscience and psychological science, artificial intelligence and other fields, the progress of brain-computer interface engineering has accelerated, and the development of industrialization has accelerated significantly. At the opening match of the 2014 Brazil World Cup, paraplegic youth Giuliano Pinto kicked off the football match with the assistance of brain-computer interface technology; in 2016, during the flight of the Shenzhou 11 manned spacecraft, Chinese astronauts completed the first space brain-computer interaction experiment; many international teams helped patients realize functions such as "typing in thoughts" and "talking in thoughts" through brain-computer interface technology...

The technological development of brain-computer interfaces is not explosive, but is progressive over time. In the 1960s, scientists began to study the connection between brain waves and computers. By recording EEG and performing simple analysis of brain wave signals, they tried to simply interpret brain waves and realize their interaction with external devices. During this period, brain-computer interface technology was not yet mature. In 1973, computer science professor Jacques Vidal first proposed the term "brain-computer interface" in academic journals. In the 1990s, with the advancement of computer technology and neuroscience, researchers achieved preliminary experiments in controlling external devices through the brain. In 1998, researchers successfully achieved the movement of the monkeys through brain waves. At this stage, the equipment and interfaces are still relatively bulky and the signal decoding accuracy is limited, but it provides valuable experience for later improvements. In 2000, the recognized concept of brain-computer interface was formally proposed. Today, brain-computer interfaces have become one of the most popular research directions in the fields of brain science, neuroscience, etc.

Multipaths move forward hand in hand, and related technologies realize multi-scenario applications

The technical paths of brain-computer interfaces mainly include invasive and non-invasive.

The invasive brain-computer interface requires direct implantation of electrodes into the cerebral cortex to obtain neural signals through surgery and other methods. The signals obtained by this type of brain-computer interface have good spatial resolution and high signal-to-noise ratio, but they need to be implanted into the body through surgical procedures. They are low in safety and cost, which can easily trigger immune responses and healing reactions, which will lead to the decay of the acquired signal or even disappear. The brain-computer interface technology of the American "Neural Connection" company is typical invasive. In early 2024, the company's founder Musk announced that the first brain chip implanted by "nerve connection" has fully recovered.

Domestic invasive brain-computer interface technology is being applied in multiple scenarios. In terms of external device control, the Zhejiang University team has implemented an invasive brain-computer interface to control the robotic arm to write Chinese characters. In terms of medical rehabilitation, the Tsinghua University team has developed a wireless, small invasive brain-computer interface system that can be placed on the sensorimotor cortex of the brain to help paralyzed patients with spinal cord injury restore hand movements, and achieve movements such as controlling the cursor, manipulating the wheelchair, and drinking water independently. In terms of language decoding, Huashan Hospital and its cooperative team have successively carried out clinical trials of high-precision real-time motion decoding and language decoding, realizing "brain control" smart devices and "ideas dialogue". It can be seen that invasive brain-computer interfaces are expected to bring more breakthroughs in the fields of medical care, scientific research, etc.

The non-invasive brain-computer interface collects neural signals through electrodes directly attached to the scalp. Its advantage is that the discharge activity of population neurons can be directly monitored on the scalp, which is simple to operate, low cost, does not need to damage the body, and does not cause an immune response. However, due to the attenuation effect of the skull on the signal and the dispersion and fuzziness of the electromagnetic waves on neurons, the signals recorded by the non-invasive brain-computer interface have low spatial resolution, weak amplitude and relatively low signal-to-noise, which requires high performance requirements for subsequent signal processing algorithms.

In recent years, my country's non-invasive brain-computer interface has made significant progress and reached the world's advanced level. In the field of basic components, Tianjin University and China Electronics Cloud Brain, a subsidiary of China Electronics Information Industry Group, jointly developed the world's first brain-computer interface codec chip "Brain Speecher" with completely independent intellectual property rights. In terms of neurorehabilitation, the full spectrum of innovative brain-computer interaction medical devices of "Shengong" brain-computer interaction has been launched, and the first idea of "brain-computer-body" collaborative neural function reconstruction has been created, achieving the synchronous integration and coordination of cortical and muscle activities by active training, and has achieved a major breakthrough in the field of sports rehabilitation. In terms of special applications such as manned space flight, the sixth-generation Chinese space station on-orbit EEG testing project has developed a space station brain function evaluation and regulation technology with completely independent intellectual property rights around brain load, brain fatigue, alertness, etc., and successfully completed the first phased goal task. In terms of consumer-grade brain-computer fusion products, my country's first comprehensive open source software platform for brain-computer interfaces has been released, building an intelligent ecological industry platform across the fields of medical care, education, entertainment, national defense, transportation, etc. Due to its security and non-invasive advantages, the non-invasive brain-computer interface has a wider audience and greater application potential. It is expected to subvert the existing life and production methods of human beings in the fields of medical care, scientific research, industry, education, entertainment, national defense, etc.

It is worth noting that on-chip brain-computer interface, that is, brain-like tissue cultivated on electrode chips, provides new ideas for the development of brain-computer interface technology. The Haihe Laboratory of Brain-Computer Interaction and Human-Computer Integration has created a "brain-like organ" with biological intelligence outside the human body, realizing the cultivation of the "brain"'s visual perception of the target and unmanned control of robots' obstacle avoidance, tracking, and grasping tasks, and has completed the inspiration of a variety of brain-type computing. As an emerging branch in the field of brain-computer interface, on-chip brain-computer interface is of great significance to exploring the fusion interaction of a new generation of life-non-life forms, and is of great significance in new applications in major national needs such as hybrid intelligence, brain-like intelligence, and medical rehabilitation.

Making a "really useful, useful" brain-computer interface

The brain-computer interface integrates advanced theories and cutting-edge technologies in multiple disciplines such as medicine, computer, electronics, machinery, and materials. In such a relatively long technology chain, the technical shortcomings in any link will hinder its industrialization process.

my country's brain-computer interface market is incubation and development and has attracted widespread attention from all walks of life. In recent years, researchers have been committed to establishing a natural interaction model of brain-computer and gradually realizing the free expression of intentions. At the same time, the application scenarios of brain-computer interfaces have gradually expanded to many fields such as medical care, aerospace, and smart home. A series of achievements such as purely thought-controlled artificial neural robots for stroke rehabilitation, as well as space brain-computer interface systems, brain-controlled spelling devices, etc. In the future, researchers will be committed to establishing a two-way brain-computer reading and writing system to efficiently and accurately interpret more complex brain intentions and achieve deep integration of human-computers.

We must also clearly realize that my country's brain-computer interface companies currently lack a sound technology chain and a complete talent chain, resulting in weak industrialization capabilities, and there is still a long way to go from experiments to daily practice.

In my opinion, various invasive technologies have ethical and security risks. The non-invasive brain-computer interface has high security, a large audience, and broad industrial prospects. my country has good technical accumulation and is currently in an important period of opportunity for the research and development of new generation technologies and accelerating the industrialization process. At this stage, we should encourage core technology research and research on common key issues, and carry out original and subversive frontier exploration of "no man's land".

In terms of selection of research directions, the market-oriented approach should drive the application transformation of scientific and technological achievements and the generation of new quality productivity, and make a "really useful and useful" brain-computer interface. Focusing on the transformation needs of major engineering applications, we will plan and design in accordance with the two technical paths of non-invasive and invasive, promote technical research together, promote the improvement of industrialized and systematic development paths, and promote my country's accelerated development in the field of brain-computer interfaces.

As an emerging technology field, there is a huge gap in related professional talents in the domestic brain-computer interface market, making it difficult for small-scale enterprises to establish a complete talent chain and technology chain. This requires guiding high-level universities to cultivate high-quality and compound talents through the establishment of interdisciplinary methods. At the same time, schools and enterprises are encouraged to jointly build high-level scientific research and innovation platforms, jointly undertake key research tasks in the field of brain-computer interfaces, solve the problems of industrialization implementation, and establish a sound and healthy brain-computer interface industry chain. Tianjin University has opened the first major in brain-computer interface in the country and officially recruited students. We hope to take this opportunity to drive the brain-computer interface and related industries to open up the technical chain and complete the talent chain as soon as possible, build a reliable base for the high-quality development of the brain-computer interface industry chain, and improve the brain-computer interface industrialization capabilities.

Brain-computer interface will not only provide new solutions for medical care and improve human quality of life, but will also have a profound impact on social structure, economic model and other aspects. As technology develops, the application of brain-computer interfaces may revolutionize the way we interact with the outside world, further blurring the boundaries between humans and machines. However, this will also be accompanied by a complex set of ethical, privacy and social issues. How to ensure the fairness, security and universality of brain-computer interfaces and how to balance technological innovation with potential risks will be a common issue facing human society.

(The author is the vice president of Tianjin University)

"People's Daily" (Page 06, January 18, 2025)