Tuesday, June 3, 2008

Back to 1984: Scientists develop technology to read your mind

Pittsburgh (PA) – Scientists from Carnegie Mellon University claim to have found a way to predict brain activity when someone thinks about specific words. So far, the catalog of words supported by the technology is limited to only 60 words. However, the simple fact that computers are able to detect thoughts based on words not only offers new opportunities in research such as thought disorders, but put the meaning of Big Brother into whole new category.

Depending on how you look at Carnegie Mellon’s announcement, the research results presented can be both impressive and scary. It is the first time we know of that scientists are actually able to dive into your thoughts and uncovering without very little doubt what words you are currently thinking of. If these findings in fact are accurate and any indications what we may see in the not too distant future, we could see giant leaps in brain activity research that could provide more insight study of autism, disorders of thought such as paranoid schizophrenia, and semantic dementias such as Pick's disease. Of course, it could also be another dimension of privacy invasion.

Tom Mitchell, and a cognitive neuroscientist, Marcel Just, both of Carnegie Mellon University, had previously shown that that functional magnetic resonance imaging (fMRI) can detect and locate brain activity when a person thinks about a specific word. Using this data, the researchers claim to have developed a computational model that enabled a computer to correctly determine what word a research subject was thinking about by analyzing brain scan data.

Based on this technology, Just and Mitchell said that fMRI data allowed them to develop a complex computational model that can predict the brain activation patterns associated with concrete nouns, or things that we experience through our senses, even if the computer did not already have the fMRI data for that specific noun: 60 nouns were organized in twelve categories including animals, body parts, buildings, clothing, insects, vehicles and vegetables. The model also analyzed a text corpus, or a set of texts that contained more than a trillion words, noting how each noun was used in relation to a set of 25 verbs associated with sensory or motor functions. Combining the brain scan information with the analysis of the text corpus, the computer then predicted the brain activity pattern of thousands of other concrete nouns.

The result? According to the scientists, the computer can effectively predict what each participant's brain activation patterns would look like when each thought about these words, even without having seen the patterns associated with those words in advance.

"We believe we have identified a number of the basic building blocks that the brain uses to represent meaning," Mitchell said. "Coupled with computational methods that capture the meaning of a word by how it is used in text files, these building blocks can be assembled to predict neural activation patterns for any concrete noun. And we have found that these predictions are quite accurate for words where fMRI data is available to test them."

"We are fundamentally perceivers and actors," Just said. "So the brain represents the meaning of a concrete noun in areas of the brain associated with how people sense it or manipulate it. The meaning of an apple, for instance, is represented in brain areas responsible for tasting, for smelling, for chewing. An apple is what you do with it. Our work is a small but important step in breaking the brain's code."

The scientists also found “significant activation” in other areas, including frontal areas associated with planning functions and long-term memory. When someone thinks of an apple, for instance, this might trigger memories of the last time the person ate an apple, or initiate thoughts about how to obtain an apple, they said.

As interesting as these research results sound, the advances in brain scanning could make you feel uncomfortable and Eric Arthur Blair, better known by his pseudonym George Orwell, may say that his vision of a society outlined in “1984” is not impossible after all, at least from a technology point of view. 1984 was published in 1949. Blair died in 1950.

Original here

No comments: