Researchers at University of Toronto and Bloorview, Canada's largest children's rehabilitation hospital, have developed a technique that uses infrared light brain imaging to decode preference. When children with disabilities can't speak or gesture to control their environment, they may develop a learned helplessness that impedes development. The researchers envision creating a portable, near-infrared sensor that rests on the forehead and relies on wireless technology, opening up the world of choice to children who can't speak or move.

Most brain-computer interfaces designed to read thoughts require training, but the nine adults in this study received no training. Prior to the study they rated eight drinks on a scale of one to five. Wearing a headband fitted with fiber-optics that emit light into the pre- frontal cortex of the brain, they were shown two drinks on a computer monitor, one after the other, and asked to make a mental decision about which they liked more. After teaching the computer to recognize the unique pattern of brain activity associated with preference for each subject, the researchers accurately predicted which drink the participants liked best 80 per cent of the time.

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