Minority Report


There are few among us who haven't thought, at one time or another, "If I could only read his/her mind..."

Well, be careful what you wish for. Because somewhere in the territory jointly inhabited by your desire to understand your spouse, and by the nightmare society depicted in Minority Report, lies the science of today.

You may recall that in the world of Minority Report, there is no crime. Not since the minds of all citizens are routinely monitored for their behavioral intent. If you simply think of committing a crime, the government knows--it can even know it before you do--and that in itself is grounds for arrest. It's the ultimate in prevention.

21st century science is not there yet. Not by a long shot. Yet the foundation stones have been laid.

The cutting edge research is being done by a team of neuroscientists--led by Drs. John-Dylan Haynes and Geraint Rees--at University College London. Haynes and Rees started with a new piece of technology called functional magnetic resonance imaging (fMRI), and then they improved on it.

fMRI, according to a paper from the Wellcome Trust (which has funded the researchers' work), can be used to map the brain with "a spatial resolution of a few millimeters, representing the activity of many hundreds of thousands of neurons."

The first attempt at experimental application was simple, with the results published in late 2005. It involved fitting subjects with goggles that allowed them to see two different images at the same time, with no cross-interference, setting up what is known as "binocular rivalry." In such a situation, the brain doesn't blend the images together, it switches its awareness back and forth between them. The question was, would it be possible, using an fMRI scan, to detect the switching?

It would. The researchers were able accurately to predict which image the subject was registering, at any given moment in time.

Though this may seem primitive, and it is (relatively speaking), Dr. Rees knew that he had found the first tiny window onto consciousness itself.

"Our stream of consciousness is very complex and constantly changing, but binocular rivalry provides a simple model system," he says. "During rivalry we can experience just one of two states, but this fluctuates spontaneously and continuously just as our thoughts and experiences do in everyday life."

Other recent studies have focused on trying to use brain imaging to identify brain activity associated with lying, violent behavior and racial prejudice.

But Haynes' and Rees' newest work pushes the research in the radical and disturbing direction presaged by Minority Report. They are going after intent.

Again, the first experiment was rudimentary. Volunteers were told that they were about to see two numbers on a screen, and they had to decide ahead of time whether they were going to add or subtract them from each other.

The scientists focused their fMRI equipment on a marble-sized part of the brain known as the medial prefrontal cortex and found that the resultant scan, when analyzed by their unique software, was indeed able to determine which choice the subject had selected, with about 70% accuracy.

In another experiment, Haynes and Rees wanted to see if they could actually tap into the unconscious.

As the Wellcome article reported: "Subjects were given a brief glimpse of an oriented stimulus followed by a strong 'masking' image that erased the oriented stimulus from their awareness. 'We told them that an oriented stimulus was being shown and that they must really try and look for it, and then press a button indicating whether it was tilted left or right, even if they had to guess,' says Dr. Rees. Their responses showed that they were just guessing, so were not conscious of the orientation of the stimulus [...]"

But the researchers were able to get about 60% accuracy, which Rees calls "significantly better than chance. So our algorithm can decode from a two-second sample of brain activity what was being shown to these people, even when they are unable to consciously perceive it. We could tell more about the subjects' experience than the subjects themselves [...]"

While Rees admits that mind reading, as we commonly think of it, is a long way off, advances in neuroscience have been so rapid that scientists in the field were forced to set up their own neuroethics society late last year.

Barbara Sahakian, a professor of neuro-psychology at Cambridge University, is one member. "Do we want to become a 'Minority Report' society where we're preventing crimes that might not happen?" she asks. "For some of these techniques, it's just a matter of time [...] but we should discuss and debate it now because what we don't want is for it to leak into use in court willy nilly without people having thought about the consequences."

There are tremendous upsides in this research, of course. Scientists envision brain-controlled computers and machinery to assist the disabled, thought-controlled wheelchairs, and artificial limbs that respond in the way the person imagines moving them. And wouldn't it be nice to have a word processor that automatically displayed the words you wanted it to type?

There's a lot of blue sky ahead. As Professor Colin Blakemore, director of Britain's Medical Research Council, put it: "We shouldn't go overboard about the power of these techniques at the moment, but what you can be absolutely sure of is that these will continue to roll out and we will have more and more ability to probe people's intentions, minds, background thoughts, and emotions."

The use of brain scanners to judge whether people are likely to commit crimes is the most potentially explosive issue, but we better start dealing with it, Haynes says, because it's coming.

"We see the danger that this might become compulsory one day," he says, "but we have to be aware that if we prohibit it, we are also denying people who aren't going to commit any crime the possibility of proving their innocence."

Kind of turns the innocent until proven guilty principle on its head, doesn't it?

Posted 03-06-2007 4:33 PM by DougHornig