By measuring blood oxygen levels in the brain, researchers have discovered a way to let paralyzed patients ‘speak’ again.
It's a patient's worst nightmare: They're paralyzed from an accident or disease, and slowly, even the ability to signal by blinking is taken from them. It's called total or complete "locked-in syndrome," or LIS. Fortunately, researchers have a way to help patients with the syndrome "speak" again—by just thinking the words.
Total LIS is common among patients in late-stage Amyotrophic Lateral Sclerosis (ALS), a progressive motor neuron disease that takes away the body's ability to move. Patients with this condition can't speak, write, or blink to communicate their daily needs.
According to a study published Tuesday in PLOS Biology, a brain-computer interface inside a cap was placed on the patient's head, allowing him or her to answer yes or no questions by thinking the answers. The cap detects whether the patient is thinking yes or no by measuring changes in the brain's blood oxygen levels.
A team of researchers from the US, Italy, Switzerland, Germany, and China tested the brain-computer interface on four ALS patients over the course of 40 tests. They asked easy questions with known answers to test if the interface was working. It produced the correct yes or no answer in 70 percent of the tests, according to a release.
Researchers also asked patients if they were happy, and the majority said they were. But quality of life could be improved if patients were able to tell caregivers how they're feeling throughout the day, researchers said.
"If we could make this technique widely available, it could have a huge impact on the day-to-day life of people with completely locked-in syndrome," said Niels Birbaumer, a study author at the Wyss Center for Bio and Neuroengineering in Geneva, Switzerland.
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