Beginner
fMRI (functional MRI)
Also known as: Functional magnetic resonance imaging, BOLD
A brain scan that maps activity by detecting changes in blood oxygen. Very detailed in space, slow in time, and needs a large scanner.
fMRI is a key research tool for working out where things happen in the brain. Researchers have used it to reconstruct rough images and sentences that people are seeing or hearing. It’s impractical for everyday BCIs because of the size and cost of the machine.
Last updated Sep 30, 2026. Educational content, not medical advice.