
The NIRS/EEG brain-computer interface system is worn by a model in Switzerland. [Photo courtesy Laurent Bouvier/Wyss Centre/Handout]
The system was tested with four patients with complete locked-in syndrome who couldn’t even move their eyes to communicate and had amyotrophic lateral sclerosis (ALS).
ALS is a neurodegenerative disease affecting nerve cells in the brain and spinal cord. Motor neurons get transported through the body to the spinal cord and to muscles. When the motor neurons begin to degenerate and die, the brain loses the ability to initiate and control muscle movement. Approximately 20,000 Americans have ALS, with 15 new cases occurring daily, according to the ALS Association.
The non-invasive BCI technique uses near-infrared spectroscopy and electroencephalography (EEG) technologies to measure blood oxygenation and the natural electrical activity in the brain. The researchers asked yes or no questions that they knew the answer to, much like a polygraph test.
“The machine records the blood flow … and calculates how (it) changes during ‘yes’ and during ‘no,’ and the computer develops an idea, a pattern,” said Niels Birbaumer, a neuroscientist at Switzerland’s Wyss Center for Bio and Neuroengineering and lead author on the study. (Other researchers hailed from Germany, the U.S. and China.)
Participants were questioned over a couple of weeks and each time the questions elicited correct responses 7 out of 10 times with the BCI technique.
The research team hopes that the results from this study will help the technology develop into something that can help people who have paralysis from stroke, spinal cord injury or ALS.
The study was published in the journal PLOS Biology and was funded by grants from Deutsche Forschungsgemeinschaft, German Ministry of Education and Research, Baden-Württemberg Stiftung, EMOIO from the Federal Ministry of Education and Research, Eva and Horst Köhler-Stiftung, National Natural Science Foundation of China and EU grant LUMINOUS.
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