Wireless Router Controls Brain Cells in Mice
CREDIT: Skypixel | Dreamstime
A startup has created "a wireless router for the brain" that allows researchers to control brain cells in mice and other small lab animals. The device lets scientists easily turn brain cells on and off in living mice that are wearing the router. Researchers watch how the mice respond to find which brain cells are connected with different behaviors.
The basic technique that the router uses is actually several years old. In 2005, researchers at Stanford University created a technique to examine brain cells by controlling them using flashes of light. Studies that use this light control help scientists understand what the brain's complex networks are doing when they're acting normally and when they're diseased, like with Parkinson's disease, Karl Deisseroth, the technique's creator, wrote in Scientific American. The technique is "God's gift to neurophysiologists," Robert Desimone, director of the brain research institute at the Massachusetts Institute of Technology, told Nature News in 2010. (MIT's Technology Review reported the news of the brain's "wireless router.")
Brain cells don't normally respond to light, but researchers can add light-sensitive genes to brain cells grown in dishes in the lab or inject the genes into a lab animal's brain. After the brain cells take up the genes, researchers can then turn cells on and off by aiming lasers at them.
The catch is getting that laser light into the brains of a living lab mouse. Right now, researchers have to thread a fiber-optic cable into the mouse's brain, leaving the animal to trail around a wire that's coming out of its head (Check out this photo in the Wall Street Journal.) This makes it difficult for the mouse to move around normally afterward, so scientists can't study its natural responses to brain stimulation. "You almost can't do any behavioral experiment in a meaningful way," University of Pennsylvania neurosurgeon Casey Halpern told Technology Review.
The new device, made by Kendall Research, delivers light to mouse brains wirelessly through a 3-gram implant. (Mice weigh about 58 grams, according to this website). The light comes from LEDs instead of the traditional lasers. Supercapacitors located under the mouse's cage power the implant and a USB controller wirelessly connects the implant to a computer, where researchers can enter in the experiments they want to do.
The implant is in beta testing with researchers, including Halpern, who studies how turning off certain brain cells affect the way mice eat.