Food for Thought

Our brains allow us to climb mountains, write poems, and investigate distant galaxies. But this comes at a price: the brain consumes a fifth of the body's energy. The bloodstream feeds the brain – if it's cut off for just a few minutes, the damage is irreversible. Luckily, we've evolved ways to control the brain's blood supply in response to its energy demands. Due to technological limits, we still don't fully understand how this works. Researchers have developed a new approach called FACED (free-space angular chirp enhanced delay). By boosting the imaging speed of microscopy, it provides unparalleled insight into the brain's blood flow. Here, the left video shows traditional microscopy, and the right shows FACED: we only see individual red blood cells in the latter. Alzheimer's disease, strokes, and ageing interrupt the brain's blood flow. The extra detail revealed by FACED may help us understand what's going wrong and how to fix it.

Written by Henry Stennett

Henry Stennett

Writer

Henry is a science communicator at Cancer Research UK and a freelance writer. He used to research microbiology but now he’s got the writing bug. Follow him on Twitter if you like: @enricostennito

• Video from work by Guanghan Meng and colleagues
• Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China and Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
• Video copyright held by original authors; reproduction permitted by PNAS
• Published in Proceedings of the National Academy of Science (PNAS), June 2022