Scientists make pivotal discovery of method for wireless modulation of neurons with X-rays that could improve the lives of patients with brain disorders. The X-ray source only requires a machine like that found in a dentist’s office.
Many people worldwide suffer from movement-related brain disorders. Epilepsy accounts for more than 50 million; essential tremor, 40 million; and Parkinson’s disease, 10 million.
Relief for some brain disorder sufferers may one day be on the way in the form of a new treatment invented by researchers from the U.S. Department of Energy’s (DOE) Argonne National Laboratory and four universities. The treatment is based on breakthroughs in both optics and genetics. It would be applicable to not only movement-related brain disorders, but also chronic depression and pain.
“Our high precision noninvasive approach could become routine with the use of a small X-ray machine, the kind commonly found in every dental office.” — Elena Rozhkova, a nanoscientist in Argonne’s Center for Nanoscale Materials
This new treatment involves stimulation of neurons deep within the brain by means of injected nanoparticles that light up when exposed to X-rays (nanoscintillators) and would eliminate an invasive brain surgery currently in use.
“Our high-precision noninvasive approach could become routine with the use of a small X-ray machine, the kind commonly found in every dental office,” said Elena Rozhkova, a lead author and a nanoscientist in Argonne’s Center for Nanoscale Materials (CNM), a DOE Office of Science User Facility.
Traditional deep brain stimulation requires an invasive neurosurgical procedure for disorders when conventional drug therapy is not an option. In the traditional procedure, approved by the U.S. Food and Drug Administration, surgeons implant a calibrated pulse generator under the skin (similar to a pacemaker). They then connect it with an insulated extension cord to electrodes inserted into a specific area of the brain to stimulate the surrounding neurons and regulate abnormal impulses.
“The Spanish-American scientist José Manuel Rodríguez Delgado famously demonstrated deep brain stimulation in a bullring in the 1960s,” said Vassiliy Tsytsarev, a neurobiologist from the University of Maryland and a co-author of the study. “He brought a raging bull charging at him to a standstill by sending a radio signal to an implanted electrode.”
About 15 years ago, scientists introduced a revolutionary neuromodulation technology, “optogenetics,” which relies on genetic modification of specific neurons in the brain. These neurons create a light-sensitive ion channel in the brain and, thereby, fire in response to external laser light. This approach, however, requires very thin fiberoptic wires implanted in the brain and suffers from the limited penetration depth of the laser light through biological tissues.