Think mind reading is science fiction?
Scientists have used brain scanners to detect and reconstruct the faces that people are thinking of, according to a a study accepted for publication this month in the journal NeuroImage.
In the study, scientists hooked participants up to an fMRI brain scanner -- which determines activity in different parts of the brain by measuring blood flow -- and showed them images of faces. Then, using only the brain scans, the scientists were able to create images of the faces the people were looking at.
"It is mind reading," said Alan S. Cowen, a graduate student at the University of California Berkeley who co-authored the study with professor Marvin M. Chun from Yale and Brice A. Kuhl from New York University.
The study says it is the first to try to reconstruct faces from thoughts. The photos above are the actual photos and reconstructions done in the lab.
While the reconstructions based on 30 brain readings are blurry, they approximate the true images. They got the skin color right in all of them, and 24 out of 30 reconstructions correctly detected the presence or absence of a smile.
The brain readings were worse at determining gender and hair color: About two-thirds of the reconstructions clearly detected the gender, and only half got hair color correct.
"There's definitely room for improvement," Cowen said, adding that these experiments were conducted two years ago, though they only recently were accepted for publication. He said he and others have been working on improving the process in the interim.
"I'm applying more sophisticated mathematical models [to the brain scan results], so the results should get better," he said.
To tease out faces based on brain activity, the scientists showed participants in the study 300 faces while recording their brain activity. Then they showed the participants 30 new faces and used their previously recorded patterns to create 30 images based only on their brain scans.
Once the technology improves, Cowen said, applications could range from better understanding mental disorders, to recording dreams, to solving crimes.
"You can see how people perceive faces depending on different disorders, like autism -- and use that to help diagnose therapies," he said.