Researchers at MIT have developed a new technique to stimulate deep brain regions without the need for invasive implants. Currently, clinicians perform deep brain stimulation by placing electrodes into the brain to stimulate specific areas. As the therapy is so invasive, only patients with serious conditions like Parkinson’s disease undergo treatment. The MIT scientists have developed a way to stimulate deep brain regions using electrodes on the scalp, which could potentially revolutionize the way the procedure is performed.
The new technique, called temporally interfering stimulation, involves crossing two high frequency electrical signals at the specific brain region that needs to be stimulated. The two signals interfere with each other, resulting in a low frequency signal at the target area. As low frequency signals can provoke neurons to fire, while high frequency signals don’t, the targeted area is activated while the surrounding tissue isn’t.
The researchers tried the system in live mice, and confirmed that they could activate highly specific brain regions. They were able to wiggle a mouse’s paws, whiskers, and ears, and did not find any evidence that the technique was causing neuronal damage. However, the team doesn’t yet understand exactly how the technique works. The method will open up a wide range of possibilities in terms of researching the brain. “People have used non-invasive brain stimulation to study a wide variety of phenomena, from mood to memory to driving ability to trust,” says Ed Boyden, a professor at the MIT Media Lab and McGovern Institute for Brain Research. “Now, we can do these types of studies, hopefully, in deeper targets in the brain.”