How illuminating! Scientists light up the nerve paths of an entire mouse.

Around the same time that Stanley Kubrick released his sci-fi epic “2001: A Space Odyssey, came another science fiction movie that took a journey of a different kind. “Fantastic Voyage” described the perilous adventures of a miniaturized crew who venture into the body of an injured scientist to repair his injured brain. I thought of that movie when I saw this recent article in the New York Times by Nicholas St. Fleur. The piece described successful efforts by German neuroscientists from Ludwig Maximilians University to make the entire body of a mouse transparent and to light up the nerve paths found throughout the body. This “fly on the wall” concept called Udisco, enabled scientists to trace neurons from the rodent’s brain and spinal cord all the way to its fingers and toes. The findings, published in Nature Methods, opens the door to a better way of studying neurodegenerative disorders, particularly traumatic brain injuries, that have few if any effective treatments. Researchers often study these diseases by examining thin slices of brain tissue under a microscope. But as Ali Ertürk, the neuroscientist who led the Udisco study notes, when you cut the brain you also cut the neurons. “The best way to look at it is to look at the entire organism, not only the brain lesion but beyond that. We need to see the whole picture.”

—Senior Scientific Writer Regina McEnery