Researchers at the Washington University School of Medicine, St. Louis, and University of Illinois, Urbana-Champaign, are developing at tissue implant that is one-tenth the width of a human hair and can control neurons with drugs and lights in mice’s brains. The device offers an advantage over current methods of studying neural circuits, which often require surgery that can damage parts of the brain or disrupt animals’ natural movements.
The researchers’ implant includes nanomanufacturing that lets scientists penetrate deep inside the brain with minimal damage, John Rogers, professor of materials science and engineering at University of Illinois, Urbana-Champaign and senior author on the study, said in a statement. The implant has room for up to four drugs and includes material at the bottom of the drug reservoirs that controls delivery. When the temperature on an electric heater rises, then the bottom expands and pushes the drug out into the brain.
Scientists tested the devices’ drug delivery potential by implanting it in mice’s brains, and found that in some experiments, they could map circuits by using the implant to inject viruses that label cells with genetic dyes. In other tests, the researchers made the mice walk in circles by injecting a drug that mimics morphine into a certain area of the brain. The team published their findings online in the journal Cell.
The researchers’ work represents “the kind of revolutionary tool development that neuroscientists need to map out brain activity” and is “in line with the goals of the NIH’s BRAIN Initiative,” James Gnadt, program director at the NIH’s National Institute of Neurological Disorders and Stroke, said in a statement. Last year, an NIH advisory committee called for $4.5 billion in funding for the 12-year Brain Research through Advancing Innovative Neurotechnologies (BRAIN) program to spur neurological research.
In September 2014, the NIH awarded $46 million to 100 investigators in the U.S. and three other countries to jump-start the initiative. If all goes to plan, the program will help improve technologies for studying the brain and allow researchers to gain a better understanding of human cognition and behavior, the NIH said at the time. “How do the billions of cells in our brain control our thoughts, feelings, and movements? That’s ultimately what the BRAIN Initiative is about,” Dr. Thomas Insel, director of the NIH’s National Institute of Mental Health, said in a statement. “Understanding this will greatly help us meet the rising challenges that brain disorders pose for the future health of the nation.”
REFERENCE: Fierce Medical Devices; 20 JUL 2015; Emily Wasserman