Nobel medicine prize goes to 3 scientists for shining light on brain activity

STOCKHOLM (AP) — The Nobel Prize in medicine was awarded Monday to three scientists whose work led to a tool that uses light to help unravel how the brain works.Dr. Karl Deisseroth, Peter Hegemann and Georg Nagel carried out research that opened a new field with the wonky name optogenetics, combining light with genes to switch on and off neurons in living brains.Separate research from the trio — one of whom lives in the U.S. and two in Germany — resulted in a technique that helps to identify neural pathways responsible for behavior and disease.

It could lead to treatments, such as restoring some vision in people with a genetic form of blindness.Experts said the advancements greatly expanded the understanding of how the brain is organized.“It has let us go from a ‘Rand McNally’ road atlas of the brain to something more akin to ‘Google Earth,’” neuroscientist Patrick Forcelli of Georgetown University said in an email.Deisseroth, 54, is a Howard Hughes Medical Institute investigator and Stanford University professor in California. Hegemann, 71, is at Humboldt University in Berlin, and Nagel, 73, most recently worked at the University of Würzburg, also in Germany, the assembly said.Winning research shines a light into the brainThe breakthrough began when Hegemann explored how a single-cell type of green algae can swim toward light. He and Nagel discovered a particular protein that, when illuminated by blue light, opens a channel to create an electrical impulse.

Putting that protein into other cells makes them light-sensitive.Brain cells use electrical signals to communicate with each other, but normally they don't respond to light, Deisseroth told The Associated Press. He used what he calls “a trick from nature," putting the gene that controls that microbial protein into certain cells in the brains of living mice.Beaming light at those cells — first by using tiny fibers, now with noninvasive methods — can turn neurons on or off while animals do various tasks.“People usually think about light as a way of collecting information to observe things,” he told the AP. This is using light to control things, to make things happen, and to do it in a very precise way.”Optogenetics is mostly a research tool to learn how specific neurons and neural circuits work.That “gives you, inevitably, ideas for how to correct things that go wrong,” D…