In recent years, with the continuous development of brain computer interface technology, scenes that used to only exist in science fiction movies have frequently appeared in our field of vision.

Recently, a research team from Tsinghua University announced two cases, in which two patients with high-level paraplegia achieved mind control cursor movement and mind control glove exoskeleton grip through wireless minimally invasive brain computer interfaces. One of the patients experienced quadriplegia for the first time in 14 years, achieving "drinking water with their hands".

Paraplegic patients rely on their thoughts

Control cursor movement and grip

35 year old paraplegic patient Xiaobai underwent wireless minimally invasive brain computer interface implantation surgery in December last year. After more than two months of rehabilitation training, he is now able to control cursor movement with his mind. The doctor introduced that through the brain computer interface, neural signals from the brain's motor areas can be obtained, and then decoded to reflect the patient's motor intention, thereby achieving "mind control activity".



The other patient is Mr. Yang, who has been paralyzed for 14 years. He underwent implantation surgery in October last year, which was also the first wireless minimally invasive brain machine implantation surgery in China. At present, Mr. Yang has partially restored the grip function by controlling the exoskeleton of the gloves with his mind, and can bring the water bottle or object to the designated position in an average of ten seconds.



Mr. Yang placed the water bottle in the designated position according to the instructions

Not only that, he was also able to control the robotic arm with brain signals freely, and for the first time after paralysis, he picked up a water bottle to drink water on his own.

Mr. Yang said, "As you think about it (holding a water bottle), you can grab it. Being old and happy is very helpful for improving the quality of life." Mr. Yang's wife was also very surprised by this, and she hopes that with the advancement of technology, Mr. Yang can independently complete more daily activities.

Mind control action

How to achieve it?

Experts introduce that the device implanted in Mr. Yang's head, which is only the size of a coin, integrates a brain computer interface processor, wireless communication and power supply interfaces, and electrodes used to collect EEG waves. The implantation site is located on the outer side of the skull, with only the electrode entering the skull and sticking to the outside of the dura mater. In addition, this system also includes an information collection and power supply module, an EEG decoding and translation module, and an exoskeleton for pneumatic gloves.



There are two coils inside and outside the patient's body, which can supply electricity through the skin and transmit brain signals from the patient's brain, achieving wireless power supply and communication. The collected signals are then used to command the pneumatic glove exoskeleton.



According to experts, brain computer interfaces are divided into three categories: non-invasive, invasive, and semi invasive:

The non-invasive brain computer interface collects EEG waves through the scalp, which has the highest safety but low signal quality and limited functionality;

Invasive direct implantation of electrodes into the cerebral cortex can obtain the highest quality neural signals, but it is highly traumatic and risky for patients;

The wireless minimally invasive brain computer interface developed by Tsinghua University is semi invasive, with electrodes implanted outside the patient's brain dura mater without damaging nerve tissue. It can obtain high signal intensity and resolution, while reducing the risk of immune response and nerve cell damage.

Wide application prospects of brain computer interfaces

Or it can be used to treat epilepsy, cognitive impairment, etc

Currently, major countries around the world view the future as the "era of neuroscience", and China also launched the "Brain Plan" in 2017, with brain computer interfaces being an important component.

Pu Muming, academician of the CAS Member and academic director of the Brain Intelligence Excellence Center of the Chinese Academy of Sciences, said that the current application of brain computer interface is mainly in the medical field. The clinical trials of brain computer interface conducted by global scientists are mostly aimed at functional recovery of patients with high paraplegia.

In this clinical trial, in addition to reading information from the motor cortex of the brain, the joint team also specifically designed a recording channel for sensory information in the brain. "Not only does the motor cortex have records, but it also has a sensory cortex that can record feedback information."



When the brain is able to receive feedback information on actions, action thinking forms a complete information loop, which will greatly enhance the effectiveness of brain computer interfaces in the field of neuromedicine. Pu Muming introduced, "For example, epilepsy treatment can stop stimulating after it has an effect, which is a closed-loop system."

Next, the team's goal is to iteratively develop a universal minimally invasive brain computer interface platform for the rehabilitation of more brain diseases such as epilepsy and cognitive impairment.