Canadian researchers have developed a "mind reading" technology that can predict which of two items a person will prefer with 80 percent accuracy.

Devised at the University of Toronto to aid children who cannot move or speak, the infrared scanner picks up brain patterns involved in very simple preference - such as which kind of soda you would like to drink. A paper on the device was published this week in the Journal of Neural Engineering.

According to the University of Toronto:

Wearing a headband fitted with fibre-optics that emit light into the pre-frontal cortex of the brain, [test subjects] were shown two drinks on a computer monitor, one after the other, and asked to make a mental decision about which they liked more.

"When your brain is active, the oxygen in your blood increases and depending on the concentration, it absorbs more or less light," [researcher Sheena] Luu said. "In some people, their brains are more active when they don't like something, and in some people they're more active when they do like something."

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.

The device functions by measuring patterns of near-infrared light absorption into brain tissues. Luu added that the device can only work for simple preference decisions, and that the brain is far too complex for the device to read thoughts that go beyond "I would prefer this chair to that chair." She hopes the device, when perfected, will help fully paralyzed people express preferences in their daily lives.

SOURCES:

University of Toronto

Journal of Neural Engineering

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