Brain decoding has always had a data problem. Every brain responds a little differently, so a system trained on one person cannot simply be used on another. Gathering enough scans is slow, costly and uncomfortable for the volunteers lying in the scanner.
The Weizmann team worked with the Natural Scenes Dataset, a public collection from eight volunteers who each viewed thousands of photos across dozens of scanning sessions, more than 70,000 images in all. The researchers split each person’s scans into about 40,000 tiny three-dimensional units called voxels and tracked how each one responded to colors, positions, and things like faces or food.
Then they looked for patterns shared across all eight brains. Their encoder, the part that predicts brain activity from an image, sorted those responses into 128 “functional regions” that behave the same way in different people, even when they sit in slightly different places. Some were already known to neuroscientists. Others were new, including a split inside the brain area that handles places, with one part reacting to indoor scenes and another to outdoor ones.
Because the encoder can predict brain responses to any photo, the team fed it extra pictures no volunteer had ever seen. Those predicted scans became training material for the decoder, which turns brain activity back into images. In effect, the model built itself a much larger practice set without anyone spending more time in a scanner.
The result: with one hour of scans from a new person, Brain-IT matches what earlier methods achieved with about 40 hours.