New Method Allows Scientists to Read Letters in a Person's Brain Scan

It's not exactly "mind reading," per se, but a team of researchers have developed a method through which they are able to determine what letter a person is looking at based on a scan of their brain.

Published in the journal Neuroimage, the study includes using an fMRI to scan a person's brain while he or she views a specific image. An fMRI works by determining where in the brain blood is flowing most and has long been used in research designed to determine which brain areas are most active while a person performs a given task.

However, researchers from the Donders Institute for Brain, Cognition and Behavior at Radboud University in the the Netherlands have taken it one step further, taking that data and using it to "teach" a mathematical model to translate patterns of brain activity into an image reflective of the one viewed by the subject.

In this case, the researchers used it to spell the word "BRAINS" by having people look at handwritten signs of each individual letter.

As the participants examined each letter, the fMRI created a fuzzy, "speckled" version of it that was then translated into a clear image of the letter using a computer model developed by the researchers.

"We gave the model prior knowledge: we taught it what letters look like," lead researcher Marcel van Gerven explained. "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, the scientist said, "was the actual letter, a true reconstruction."

This process of recognition and learning is reflective of how a person comes to read, for example, van Gerven said. 

"And this is exactly what we are looking for: models that show what is happening in the brain in a realistic fashion."

Going forward, the researcher hopes to improve the models so as to apply them to working memory or subjective experiences, including dreams or visualizations.