Scientists can now read your thoughts

For the first time scientists have come nearer to penetrate into the mind and read your thoughts with the help of an MRI scan in a virtual reality environment on the basis of the pattern of activity in the brain, in a study conducted at the University College London.

Researchers have shown that they can tell where a person is "standing" within a virtual reality room on the basis of the pattern of activity in the brain alone offering compelling evidence that the hippocampus, a region of the brain critical to navigation, memory, and imagining future experiences, works in a structured and predictable way.

"You can predict where someone is standing by reading the patterns in their brain activity," said Demis Hassabis of University College London. "You can track what is purely an internal thought."

"With this kind of research, we are approaching the realm of mindreading," added Eleanor Maguire, also of University College London.

''It's also a small step towards the idea of mind reading, because just by looking at neural activity, we are able to say what someone is thinking.''

In the new study, Hassabis, Maguire, and their colleagues asked four participants to navigate to target locations within a virtual reality room while their brains were scanned with a functional magnetic resonance imager (fMRI). fMRI measures blood flow related to neural activity in the brain. They then applied a sophisticated analytical procedure known as multivariate pattern classification to see if they could relate the pattern of brain activity to each individual's location in virtual space.

The pattern they uncovered reflected the participants' memory for where they were, the researchers explained, since once they had reached their final destination, there were no visual cues to discern one target spot from another. The activity they examined spanned some two to five million of the 40 million or so cells in the hippocampus, Hassabis noted.

Earlier studies done primarily in rats had suggested that spatial memories stored in the hippocampus had neuronal representations that were uniform and randomly distributed. But if that were the whole story, the predictions made in the new study would not have been possible.

Now that they have shown that such a predictable functional structure exists in the hippocampus, additional studies will seek to crack that neural code for other memories.

Indeed, spatial representations of the type investigated in the study are thought to form the scaffold upon which memories of our personal experiences, known as episodic memories, are built.

Dr Hassabis said, ''It would be impossible to use the technique to detect whether somebody is lying or not, because they could easily fool the system just by lying during the training sessions. The current techniques are a long way away from doing those kinds of things, though in the future they may become more possible. It might be useful to start having those kinds of ethical discussions in the near future in preparation.''

Although the research could shed light on disorders that involve changes to brain structure or memory loss, such as amnesia, dementia and stroke, it does not suggest that MRI mind-reading could soon be used to detect lies or reveal thoughts without their consent.

"We know that the hippocampus is critical for remembering our life experiences," Maguire said. This discovery "opens a whole world of possibility previously thought inaccessible to human brain imaging."