A technique for studying individual circuits in the brains of mice has been hampered because the light needed to stimulate neural activity briefly overwhelms the electrodes ‘listening’ for the response. Now, improved shielding within the neural probe enables those lost signals to be captured.

«Consider a conversation, in which the first few and the last few words of a sentence are omitted or distorted. In such a dialogue, not much information can be reliably deciphered. This is the same situation in our research,» said Gyorgy Buzsaki, the Biggs Professor of Neuroscience at New York University School of Medicine and a co-author of the new paper describing the results.

«Our dialogue with brain circuits starts with a question in the form of a light pulse. If the beginning and the end of the pulse — our ‘question’ — produce large artifacts, we lose the instantaneous and often very critical neuronal responses.»

To address this problem, a team of engineers at the University of Michigan set out to improve their neural probe so that it could record complete answers. This enables experiments that were previously impossible.

«As an example, we can mimic a brain wave by turning on the micro-LEDs at a certain frequency and see how the neural circuit behaves. We can also implement what is called a closed-loop control and make the LEDs turn on as soon as we detect a certain brain signal,» said Kanghwan Kim, first author on the new paper in Nature Communications and a recent Ph.D. graduate in electrical and computer engineering from U-M.

Understanding communication among brain cells is key to advancing our understanding of the brain and developing treatments for neurological diseases such as Alzheimer’s Disease. One of the new experiments that the team has in mind would explore memory.

Story Source:
Materials provided by University of Michigan. Original written by Kate McAlpine. Note: Content may be edited for style and length.