2012 Computational and Systems Neuroscience Meeting

How the worm bends

SALT LAKE CITY—Each section of a squirming worm’s body follows the leader, a study presented February 25 at the Computational and Systems Neuroscience meeting shows. Quan Wen of Harvard University and his colleagues confirmed a long-held theory about how some worms wiggle by rigging up a device that could monitor and control the undulations of C. elegans. The device pinned the worm once near the head and again near the tail. A worm constrained like this could no longer wiggle anything but the head segment. Forcing a mid-section bend caused the tail to bend, too. The curve of one section depended on the curve of the section right before it. By stimulating the motor nerve cells responsible for the bend, the team found that a curved conformation can be set and forgotten—staying in a bend doesn’t require the constant help of motor nerve cells.—Laura Sanders

Creating a vision

SALT LAKE CITY—A flash of light shone on brain cells can make monkeys see something that’s not there. That finding comes from a technique called optogenetics, which so far has been used to influence behavior in rodents, flies and worms, but never before in primates. In the new study, presented February 25 at the Computational and Systems Neuroscience meeting, Mehrdad Jazayeri of the University of Washington in Seattle and colleagues inserted a gene for a light-responsive molecule into select nerve cells in two rhesus monkeys’ visual systems. When a burst of light hit these cells, the monkeys moved their eyes toward a particular place on a computer screen, even though nothing was there. The ability to precisely manipulate nerve cells in monkeys will allow scientists to test more complex theories about how the brain works.—Laura Sanders