"How neurons are communicating with each other? What are the pathways for information processing in the brain? These are the questions that can be answered in the future with this kind of technique," Kotov said.
"Because these devices are so small, we can combine them with emerging optical techniques to visually observe what the cells are doing in the brain while listening to their electrical signals," said Takashi Kozai, who led the project as a student in Kipke's lab and has since earned his Ph.D. "This will unlock new understanding of how the brain works on the cellular and network level."
Kipke stressed that the electrode that the team tested is not a clinical trial-ready device, but it shows that efforts to shrink electrodes toward the size of brain cells are paying off.
"The results strongly suggest that creating feasible electrode arrays at these small dimensions is a viable path forward for making longer-lasting devices," he said.
In order to listen to a neuron for long, or help people control a prosthetic as they do a natural limb, the electrodes need to be able to survive for years in the brain without doing significant damage. With only six weeks of testing, the team couldn't say for sure how the electrode would fare in the long term, but the results were promising.
"Typically, we saw a peak in immune response at two weeks, then by three weeks it subsided, and by six weeks it had already stabilized," Kotov said. "That stabilization is the important observation."
The rat's neurons and immune system got used to the electrodes, suggesting that the ele
|Contact: Nicole Casal Moore|
University of Michigan