Researchers in Korea have developed a wireless rechargeable brain implant. This device can precisely control the neural circuits of the brain with light using a smartphone without replacing the battery for a long period of time in the living body after implantation.
KAIST (President Seong-cheol Shin) announced on the 26th that the research team of Professor Jae-woong Jeong of the Department of Electrical and Electronic Engineering developed a wireless optogenetic device that is completely implanted in the brain through joint research with Professor Jeong-Hoon Kim’s team at Yonsei University.
This development technology is expected to be applied not only to brain function studies that require long-term animal experiments, but also to the human body in the future to treat mental diseases such as addiction and degenerative brain diseases such as Parkinson’s disease.
The research, which was co-authored by Dr. Choong-yeon Kim of KAIST’s Department of Electrical and Electronic Engineering and Minjung Koo, Ph. (Paper name: Soft subdermal implant capable of wireless battery charging and programmable controls for applications in optogenetics)
Optogenetics is attracting attention in the fields of brain science and neuroscience as a solution to reveal brain functions and treat various brain diseases because it can selectively and elaborately control only targeted specific neurons using light.
Existing optogenetics use a method of transmitting light to nerve cells through an optical fiber connected to an external device, but this wired method has limitations in implementing complex animal experiments in that it greatly limits the free movement of animals.
Wireless implant devices recently developed do not limit animal behavior, but have limitations in that they are not independent and are not stable because they require periodic battery replacement or wirelessly supplied power from external equipment.
The research team developed a wireless circuit that enables wireless charging of the battery and wireless control of the device and combined it with a micro LED-based probe. Through this, it is possible to wirelessly charge the battery even while the animal is moving freely, and implemented a brain fully implantable device weighing 1.4 grams (g) that can wirelessly control the photostimulation through a smartphone app. Furthermore, in order to prevent damage to the surrounding tissues by the device after the biotransplantation, the device was developed to have a soft shape like a living tissue by wrapping the device with a very soft biocompatible material.
Professor Jae-woong Jeong of KAIST, who led the research, said, “Since the device developed this time can be wirelessly charged while implanted in the body, it can be used for a long time without the need for additional surgery for battery replacement. This technology is not only a device for brain implantation, but also an artificial pacemaker. It is expected that it can be applied universally to various devices for implantation such as gastric stimulators.”
The research team confirmed that the device is completely implanted into the scalp with the LED probe inserted into the brain of the mouse, and the battery is automatically wirelessly charged while the mouse moves freely. In addition, the research team showed that light is transmitted wirelessly to specific brain regions of mice repeatedly exposed to cocaine, an addictive drug, to suppress the expression of behavioral sensitization caused by cocaine, and that optogenetics can be applied to control addictive behavior by cocaine.
Professor Jeong-Hoon Kim of Yonsei University Medical School, a co-researcher, said, “It is very interesting to see an animal that moves freely and transmits light to the brain by simply running a smartphone app, thereby controlling certain behaviors of the animal, and it stimulates a lot of imagination.” said. The research team plans to expand research to further miniaturize the device and develop it into an MRI-friendly design so that this technology can be ultimately applied to the human body.
This research was carried out with support from the Ministry of Science and ICT and the Korea Research Foundation’s basic research lab support project, new researchers support project, and KAIST global singularity research project.
