Imagine a world where your every intention is known to others. It's picked up by scanners in stores and at job interviews. Portable models take the suspense out of dating. And teenagers have implants to make it easier to disguise their real intentions from parents.

No, none of this has happened yet. But recent research at UCLA has brought it all much closer to reality.

In an experiment investigating subjects' sunscreen use, brain scans were able to predict whether subjects would be using sunscreen in the next week more accurately than the subjects themselves could predict, or at least were willing to admit to.

The researchers found that activity in a region of the medial prefrontal cortex accurately predicted subjects' use of sunscreen about 75% of the time.

Often people say they're going do something, but then don't follow through. New Year's resolutions are a good example.

The researchers used a technique known as functional magnetic resonance imaging (fMRI). When an area of the brain becomes more active, blood flow to the area increases and blood composition changes. fMRI scans are able to detect these differences and, when carefully interpreted, can reveal changes in activity in specific areas of the brain as they happen.

While being scanned, 20 young men and women read and listened to messages about sunscreen, mixed with other information so they would not know the goal of the experiment. They had previously filled out questionnaires detailing prior sunscreen usage, their attitude towards sunscreen and their future intentions to use sunscreen. After seeing and listening to the messages, the subjects answered more questions about their future intentions. Afterwards, they received gifts including sunscreen towelettes.

A week later, the researchers did a surprise follow up to find out whether the subjects had actually used sunscreen.

About half of the subjects had correctly predicted whether or not they would use sunscreen. Researchers then checked the subjects' fMRI scans to see if any specific brain activity predicted the subjects' action more accurately.

The researchers found that activity in a region of the medial prefrontal cortex accurately predicted subjects' use of sunscreen about 75% of the time. In other words, the scan predicted subjects' future behavior better than the subjects themselves did.

Naturally, this is of keen interest to advertisers and all variety of salespeople. But there's also potential for good. The researchers are now planning an experiment to test the probable effects of different anti-smoking messages on cigarette smokers, to see which messages are most effective at helping smokers to quit.

An article on the study was published in the June 23, 2010 issue of the Journal of Neuroscience.