Brain Scan News

Can brain scans read our minds?

Brain scans may be used to record images from thoughts, dreams and more.

December 12, 2008
Researchers at ATR Computational Neuroscience Laboratories in Kyoto, Japan, say they've developed new analysis technology that can reconstruct the images inside a person's brain and display them on a computer screen, according to Pink Tentacle, an English-language blog that covers news from Japan. Pink Tentacle picked up the info from Japan's Chunichi Shimbun daily newspaper.

ATR scientists reported this week in the journal Neuron that they reconstructed various images study participants were viewing by using a functional magnetic resonance imaging (fMRI) to analyze changes in the flow of blood in the brain's visual cortex (a region of the brain where vision is processed). The researchers showed each subject 400 random black-and-white images for a period of 12 seconds each. As the images were viewed, the fMRI provided information about brain activity that a computer then analyzed to determine patterns that associated each brain reaction with a particular image.

Researchers compared the blood flow in brains of participants when they were viewing familiar images as well as when they sifted through new sets of images. In one case, when they were shown images of the letters used to spell the word "neuron," the fMRI accurately reconstructed and displayed the letters that participants were seeing based solely on their brain activity. "The results suggest that our approach provides an effective means to read out complex perceptual states from brain activity while discovering information representation in multivoxel patterns," the researchers write.

Although the technology is still in the early phases of development, it paves the way for applications that until now have only been the stuff of science fiction, such as reading minds for interrogation purposes, eavesdropping on dreams as people snooze or even providing a way for physically impaired people unable to speak to communicate via their brain waves. The researchers hope the technology will one day help doctors better understand the roots of and how to treat patients suffering from psychiatric disorders by "seeing" what's going on in their brains when they're, for example, hallucinating.

fMRI has been held up as a breakthrough technology for better understanding the brain. Researchers at Columbia University in New York City are using it to study what happens in the amygdala (the brain's almond-size fear center) when people are placed in scary situations. And researchers at the University of Sheffield in England believe that fMRI is more useful than polygraphs, which have been shown to have false positives and negatives, in determining whether someone is lying.

Other scientists are skeptical. Unlike a polygraph, an fMRI uses powerful magnetic fields to detect tiny changes in blood oxygen levels in the brain that are believed to be signatures of cognitive processes. But a Penn State researcher last year published a study in the American Journal of Law and Medicine questioning whether fMRI scans are reliable markers of veracity. He reported that fMRIs are open to broad interpretation and, as such, could provide images that suggest but do not really confirm if someone is lying, which could subject innocent victims to aggressive interrogation tactics.

Source: Scientific American

Author: Larry Greenemeier

Scientific American