We’re used to turning on lights with a switch. But what about switching on other things with a light? Using optogenetics, researchers can shine a point of light at brain cells to activate or inhibit them, revealing crucial details about what’s going on. But there’s a physical limit to this, since you can only really shine a light onto the brain’s surface. To solve this, a new technique makes use of a different type of light, called near-infrared, which passes through body tissue like visible light through glass. Researchers injected a group of nanoparticles (blue) into a mouse brain, which can themselves produce visible light when hit by near-infrared light shone in from the outside. They could then stimulate previously-unreachable brain cells (red dots in the brain section pictured). Early tests successfully triggered memory recall, and the technique could help reveal new treatment options for all sorts of neurological diseases.
Written by
BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.