APRIL 15, 2009--A brain-computer interface (BCI) that can decode thought processes could enable people with severe or multiple disabilities to communicate and control external devices via thought alone. Bringing such a system one step closer, Canadian researchers have developed a way to use optical imaging to decode preference by measuring the intensity of near-infrared light absorbed in brain tissue.
The system is based on the use of near-infrared spectroscopy (NIRS) to study cerebral haemodynamics during the decision-making process. NIRS has been investigated before as a non-invasive tool for reading thoughts. But previous NIRS-BCI set-ups required user training. For example, to indicate "yes" to a question, a subject would need to perform a specific unrelated task, such as a mental calculation.
The key difference in this latest system --developed by researchers at the Bloorview Research Institute (Toronto, ON, Canada) and the University of Toronto -- is that the BCI is trained to directly decode neural signatures corresponding to specific decision.
As no secondary task is required to indicate preference, the design should be more intuitive to use, decreasing the cognitive load required to operate the interface and removing the need to train the user. For more information, go to: http://www.bloorview.ca/newsroom/stories/infrared.php