They’ve detected photons that traveled from one side of an adult human head to the other—an optical journey spanning over 15 centimeters and requiring passage through skull, brain, and bone.

Harvard scientists unveil the most detailed map of the brain ever: ‘It’s an alien world inside your own head’ The researchers, with Google and other partners, spent a decade deciphering 1 ...

More information: Jack Radford et al, Photon transport through the entire adult human head, Neurophotonics (2025). DOI: 10.1117/1.NPh.12.2.025014 Provided by University of Glasgow ...

Detecting photons through an entire adult head explores the limits of photon transport in the brain, for access to regions of the brain currently inaccessible with noninvasive optical brain ...