Do You See What I See? Translating Images out of Brain Waves

This article is about scientists from the University of California, Berkeley, report in Nature today that they have developed a method capable of decoding the patterns in visual areas of the brain to determine what someone has seen. Needless to say, the potential implications for society are sweeping. The scientists say that previous attempts to extract "mental content from brain activity" only allowed them to decode a finite number of patterns. Researchers would feed image to an individual (or ask them to think about an object) one at a time and then look for a corresponding brain activity pattern. "You would need to know [beforehand], for each thought you want to read out, what kind of pattern of activity goes with it," says John-Dylan Haynes, a professor at the Bernstein Center for Computational Neuroscience Berlin and the Max Planck Institute for Human Cognitive and Brain Sciences that was not affiliated with the new work. Researchers used functional magnetic resonance images (fMRIs) to record activity in the visual cortices of a pair of volunteers (two of the study's co-authors) while they viewed a series of images. They examined the brain by dividing the regions into voxels (volumetric units, or 3-D pixels) and noting the part of the picture to which each section responded. For instance, one voxel, or slice, might respond in a certain pattern to, say, colors in the upper left-hand corner of the photo, whereas another voxel would be set off by something in a different portion of the picture.