In the quest to understand how the brain turns sensory input into behavior, Harvard scientists have crossed a major threshold. Using precisely targeted lasers, researchers have been able to take over a tiny animal’s brain, instruct it to turn in any direction they wish, and even implant false sensory information, fooling the animal into thinking food was nearby.

As described in a Sept. 23 paper published in the journal Nature, a team made up of Sharad Ramanathan, an assistant professor of molecular and cellular biology and of applied physics; Askin Kocabas, apostdoctoral fellow in molecular and cellular biology; Ching-Han Shen,a graduate student in molecular and cellular biology; and Zengcai V. Guo, from the Howard Hughes Medical Institute, were able to take control of Caenorhabditis elegans — tiny, transparent worms — by manipulating neurons in the worms’ brain.