Watching and Learning from Flies on the March

Using a microscope, a floating foam ball, and rock-steady hands, Janelia Farm researchers have developed a way to measure the brain activity of a fruit fly while it is walking. The new technique literally creates a window into the tiny tangle of neurons in the insect’s brain, so that researchers can watch as those cells work together to let the fly move and respond to changes in its environment.Established methods had allowed researchers to image in real time as neurons in the brains of larger species, such as rats and mice, signaled to one another during behavior. The new technique, developed in the lab of Vivek Jayaraman, a group leader at the Howard Hughes Medical Institute’s Janelia Farm Research Campus, is the first to do so in the tiny brain of Drosophila melanogaster. Vivek and his collaborators demonstrated this sophisticated system in a study published July 24, 2010 in Current Biology. In that work, the researchers report that they used the technique to learn that neurons in the fly's optic lobes—regions of the brain that process vision—are tuned differently to the speed of external motion when the insect is walking and when it is stationary.Read more at...HHMI News, July 2010.