CLARITY: Seeing the Inner Workings of the Brain
Bio-X scientists have improved on their original technique for peering into the intact brain, making it more reliable and safer. The results could help scientists unravel the inner connections of how thoughts, memories or diseases arise.
Last year Karl Deisseroth, a Stanford professor of bioengineering and of psychiatry and behavioral sciences, announced a new way of peering into a brain - removed from the body - that provided spectacular fly-through views of its inner connections. Since then laboratories around the world have begun using the technique, called CLARITY, with some success, to better understand the brain's wiring.
However, Deisseroth said that with two technological fixes CLARITY could be even more broadly adopted. The first problem was that laboratories were not set up to reliably carry out the CLARITY process. Second, the most commonly available microscopy methods were not designed to image the whole transparent brain. "There have been a number of remarkable results described using CLARITY," Deisseroth said, "but we needed to address these two distinct challenges to make the technology easier to use."
In a Nature Protocols paper published June 19, Deisseroth presented solutions to both of those bottlenecks. "These transform CLARITY, making the overall process much easier and the data collection much faster," he said. He and his co-authors, including postdoctoral fellows Raju Tomer and Li Ye and graduate student Brian Hsueh, anticipate that even more scientists will now be able to take advantage of the technique to better understand the brain at a fundamental level, and also to probe the origins of brain diseases.
This paper may be the first to be published with support of the White House BRAIN Initiative, announced last year with the ambitious goal of mapping the brain's trillions of nerve connections and understanding how signals zip through those interconnected cells to control our thoughts, memories, movement and everything else that makes us us.
"This work shares the spirit of the BRAIN Initiative goal of building new technologies to understand the brain - including the human brain," said Deisseroth, who is also a Stanford Bio-X affiliated faculty member.
When you look at the brain, what you see is the fatty outer covering of the nerve cells within, which blocks microscopes from taking images of the intricate connections between deep brain cells.
The idea behind CLARITY was to eliminate that fatty covering while keeping the brain intact, complete with all its intricate inner wiring.