Scientists have figured out a way to switch brain cells on and off like light bulbs, but instead of using a clapper, they're using microbial proteins and lasers.
Ed Boyden, a neuroscientist at the Massachusetts Institute of Technology, has developed a way to shut down parts of a brain just by shining light on them. When the light is turned off, the brain switches back on [Forbes]
. The research team says their technology will help neuroscientists probe the brain's circuitry by silencing certain regions and studying the effects. The technique, which was described in the journal Nature, could one day be used to shut down overactive regions of the brain often found in people with epilepsy, depression, Parkinson's disease, and blindness. A bit of fancy genetic tinkering is required to prime the brain to respond to light.
Neurons fire when electrically charged atoms – ions – flood in and out of them, creating a tiny electric potential across their membranes [New Scientist]
. Using this knowledge, the MIT researchers built upon Boyden's 2005 discovery that demonstrated that certain microbial proteins can create a stimulating effect when genetically engineered into neurons and blasted with light. Boyden has now found a similar pair of bacterial and fungi proteins that also respond to light, but respond by shutting off their neuron hosts. What's more, one of the proteins responds to yellow light, while the other reacts to blue.
A far-off hope, especially of those who study artificial intelligence, is that using a combination of [the two new proteins] to turn off certain types of neurons along with using Boyden's earlier method of activating neurons, the brain could be manipulated in complex ways. Researchers could then learn much about how the brain processes information, better copy it and, maybe, better control it [Forbes].
Obviously, using optogenetics to treat humans is years, and maybe decades, away from reality. However, even if the technology never makes its way into medical treatments for human brains, it will certainly prove useful as a research tool for basic scientific research on brain circuitry. Related Content: 80beats: Can Laser Treatment Rejuvenate the Incandescent Bulb? 80beats: Lasers Write False, Fearful Memories into the Brains of Flies 80beats: Scientists Predict: The 2010s Will Be Freakin’ Awesome—With LasersImage: flickr / etwood