Korean Scientists Attach 'Eye' to Brain Chip

KIST Dr. Jo Il-joo's Research Team "Now Possible to Identify Location and Type of Signal-Sending Neurons"

＜Fluorescent Neural Probe System＞
An image sensor-integrated brain chip was system-level integrated to measure cell type-specific activity in the brain circuits of living mice. A compact integrated system was implemented for use in mice.

Image provided by Dr. Ilju Cho and Dr. Namseon Chu, Brain Science Institute, Korea Institute of Science and Technology (KIST)

[Asia Economy Reporter Kim Bong-su] Domestic researchers have added eyes to a brain chip. They enhanced a brain chip that measures the electrical activity of neurons by adding a camera function, allowing signals from specific cells to be identified at a glance.

On the 12th, the National Research Foundation of Korea announced that Dr. Il-Joo Cho's research team at the Korea Institute of Science and Technology (KIST) developed a brain chip the thickness of a hair that integrates photodiodes, the basic units of a camera, at high density into a brain chip measuring neural activity. This allows cell-specific fluorescent signals to be measured simultaneously with electrical signals.

Our brain is composed of various distinct regions, and neurons active in each region have different roles. If neurons can be visualized in different colors according to their types, it could serve as a foundation to realize brain disease treatment attempts that identify and stimulate only specific cells involved in diseases.

Previously, it was possible to visualize areas near the brain surface such as the cerebral cortex or hippocampus using optical fibers with a thickness of 0.5mm. However, it was difficult to simultaneously measure rapidly changing electrical signals and slower fluorescent signals. Due to their size, it was also challenging to measure deep brain areas or multiple brain regions simultaneously.

The research team succeeded in integrating photodiodes, the basic units of a camera, into an existing brain chip designed for electrical signal measurement by utilizing microfluidics and semiconductor technology. This made the chip about 30 times smaller compared to conventional optical fibers. While measuring electrical signals, the chip can simultaneously obtain the location and cell type information of the cells showing those signals through cell-specific fluorescent signals. Notably, it was produced in an array form, enabling simultaneous measurement from multiple brain regions.

Furthermore, by implanting the fabricated brain chip into the hippocampus, responsible for memory in rats, and applying photostimulation, the team confirmed that they could precisely measure the rapidly changing activity of excitatory cells among various cell types.

The research team explained, "The brain chip developed this time is expected to contribute to identifying the roles of different neuron types, providing fundamental data for strategies to stimulate specific brain circuits and cells involved in particular diseases."

The research results were published on the 19th of last month in the international journal Advanced Science.

This content was produced with the assistance of AI translation services.