Is it possible to reconstruct human thoughts? The question has long puzzled scientists and confounded philosophers, but now new research from Radboud University Nijmegen in the Netherlands suggests that with the help of MRI (magnetic resonance imaging) scanners, computers can learn to "read" letters directly from the human brain, ScienceDaily reports.
The new study, soon to be published in the journal Neuroimage, features research that goes beyond determining which areas of the brain are most active during the performance of specific tasks. A research group from Raboud's Donders Institute for Brain, Cognition and Behavior used MRI data to determine what a subject was looking at, and in this case, they were reading handwritten letters of the alphabet.
Researchers programmed an MRI scanner model to recognize how "2x2x2 mm from the brain scans - known as voxels - respond to individual pixels." When they combined the information about the pixels from the voxels that had been scanned, they were able to reconstruct a blurry (yet comprephensible) pattern depicting what the viewer was looking at and processing.
"After this we did something new," lead researcher Marcel van Gerven said to ScienceDaily. "We gave the model prior knowledge: we taught it what letters look like. This improved the recognition of the letters enormously. The model compares the letters to determine which one corresponds most exactly with the speckle image, and then pushes the results of the image towards that letter. The result was the actual letter, a true reconstruction."
Gerven explained that their approach follows the way neuroscientists believe the brain processes images, as we learn to recognize the shapes of letters and numbers while learning to read.
"We hope to improve the models to such an extent that we can also apply them to the working memory or to subjective experiences such as dreams or visualizations," Gerven said. "Reconstructions indicate whether the model you have created approaches reality."
Sanne Schoenmakers, who is working on a thesis about decoding thoughts, explained to ScienceDaily that she hopes future research on the subject can involve a more powerful MRI scanner.
"Due to the higher resolution of the scanner, we hope to be able to link the model to more detailed image," she said. "We are currently linking images of letters to 1200 voxels in the brain; with the more powerful scanner we will link images of faces to 15,000 voxels."
Click here to see a photo from the researchers in which an MRI scanner successfully determined which letters the test subject was looking at.
