New image technique could allow scanners to read minds
James Randerson, science correspondent
guardian.co.uk,
Wednesday March 5 2008

Scientists have developed a mind-reading technique that allows them to accurately predict images being viewed by people, by using scanners to study brain activity.

The breakthrough by American scientists took MRI scanning equipment normally used in surgical procedures to observe patterns of brain activity when a subject examined a range of black and white photographs.

Then a computer was able to correctly predict in nine out of 10 cases which image people were focused on - random guesswork would have been accurate only eight times in every 1,000 attempts.

The study raises the possibility in future of the technology being harnessed to visualise scenes from a person's dreams or memory.

Writing in the journal, Nature, the scientists led by Dr Jack Gallant from the University of California at Berkeley said: "Our results suggest that it may soon be possible to reconstruct a picture of a person's visual experience from measurements of brain activity alone. Imagine a general brain-reading device that could reconstruct a picture of a person's visual experience at any moment in time."

It will inevitably also raise fears that a suspect's brain could be interrogated against their will, raising the nightmarish possibility of interrogation for "thought crimes".

The researchers say this is currently firmly in the realm of science fiction because the technique can only currently be applied to visual images and to date, the experiments rely on cumbersome MRI scanning equipment and extremely powerful magnets. The software decoder itself has to be adapted to each individual during hours of training while in the scanner.

However, the team have warned about potential privacy issues in the future when scanning techniques improve. "It is possible that decoding brain actvitiy could have serious ethical and privacy implications downstream in say, the 30 - 50 year time frame," said Prof Gallant:"[We] believe strongly that no one should be subjected to any form of brain-reading process involuntarily, covertly, or without complete informed consent."

The technique relies on functional magnetic resonance imaging (fMRI), a standard technique that creates images of brain activity based on changes in blood flow to different brain regions[...]