A small brain implant can be retracted wirelessly to control brain circulation

A group of KAIST researchers and colleagues have devised a tiny brain implant that can be wirelessly recycled from the outside of the body to control brain circuits for long periods without battery recharge.

The device is constructed of ultra-soft and biodegradable polymers to help provide long-lasting compatibility with print. Aiming at micrometer-sized LEDs (equivalent to the size of a grain of salt) mounted on ultrathin probes (human hair thickness), it can wirelessly treat neurons in the deep brain using light.

This study, led by Professor Jae-Woong Jeong, is a step forward from the end-to-end neural implant device he developed in 2019. The previous version could deliver a number of drugs and mild stimulant treatment without wired using a smartphone. For more, Handling brain cells with a smartphone.

To update the new version, the research team came up with a fully automated soft optoelectronic system, which can be remotely controlled and optionally with a smartphone. This research was published on January 22, 2021 in Nature Communication.

The new wireless charging technology addresses the limitations of conventional brain implants. Wireless portable device technologies have recently become popular as alternatives to tissue-attached implants, as they help reduce stress and inflammation in freely moving animals during brain scans. , which themselves contribute to the life of the machines.

However, such devices require intermittent surgeries to replace discharged batteries, or special and bulky wireless power configurations, which limit experimental options as well as the scalability of animal testing.

“This powerful device eliminates the need for additional pain surgeries to replace a clotted battery in the implant, allowing malignant malignant neuromodulation,” said Dr. Jeong. “We believe that applying the same basic technology to different types of implants, including deep brain stimulators, and cardiac and gastric pacemakers, to relieve patients of long-term use within reduce the body. “

To enable wireless battery charge and control, researchers developed a small circuit that connects a wireless energy charger with a coil antenna and a low-energy Bluetooth chip. Another magnetic field can pass through it unevenly through a tension material, and generate electricity inside the machine to charge the battery. The battery-powered Bluetooth implant then delivers programmed light patterns to brain cells using an “easy-to-use” smartphone app for real-time brain control.

This device can be operated anywhere and anytime to handle cloud circuits, making it a highly flexible tool for monitoring brain activity. “

Choong Yeon Kim, L Study.between Author and R.esearcher, Korea Institute of Advanced Science and Technology

Neuroscientists performed these implants in rats and showed that they were able to maintain cocaine-induced behavior after the rats were injected with cocaine. This was achieved by precise light stimulation of the relevant target neurons of the brain using the smartphone-controlled LEDs. In addition, the battery in the implants could recharge while the rats were behaving freely, thus reducing any physical breakage in the tests.

“Wireless battery recharging makes experimental methods much more complex,” said co-lead author Min Jeong Ku, a researcher at Yonsei University College of Medicine.

“The fact that we can control the specific behavior of animals, by delivering light stimuli into the brain just with a simple manipulation of a smartphone app, observes animals moving freely nearby , very interesting and stimulates a lot of imagination, “said Jeong-Hoon Kim, professor of psychology at Yonsei University College of Medicine.” This technology will help different methods of brain research. “

The researchers believe this brain implant technology could lead to new opportunities for brain scan and therapeutic interventions to treat diseases in the brain and other organs.