University of California San Diego researchers have developed a neural implant capable of reading brain activity that could advance research into creating a brain-computer interface (BCI) without being overly invasive.
The new implant consists of a thin transparent strip made of a polymer with several graphene electrodes 20 micrometers in diameter, each of which is connected to a circuit board via tiny wires. The strip sits on the surface of the brain allowing it to detect neural activity consisting of electrical activity and calcium activity. Unlike previous methods, the chip allows scientists to conduct longer experiments without the need to have a subject fixed in place under a microscope.
“Since electrical recordings do not have these limitations, our technology makes it possible to conduct longer duration experiments in which the subject is free to move around and perform complex behavioral tasks,” said Mehrdad Ramezani, co-first author of the study, according to a press release from the University of California at San Diego. “This can provide a more comprehensive understanding of neural activity in dynamic, real-world scenarios.”
The new technology was tested on transgenic mice. They were then able to use surface electrical signals to predict calcium activity at varying depths in the brain as well as within individual neurons.
“We are expanding the spatial reach of neural recordings with this technology,” said Duygu Kuzum, senior author of the study. “Even though our implant resides on the brain’s surface, its design goes beyond the limits of physical sensing in that it can infer neural activity from deeper layers.”
The scientists intend to conduct further tests of the technology. “This technology can be used for so many different fundamental neuroscience investigations, and we are eager to do our part to accelerate progress in better understanding the human brain,” said Kuzum.