Brain imaging enables ALS 'locked-in' patients to answer
One patient, at the request of his family, was asked whether he'd allow his daughter to marry her boyfriend. Nine out of 10 times, he said no, the researchers said.
Scientists were impressed by the study findings, which involved advanced brain-computer technology.
"This is at the frontier in terms of communication with patients who have locked-in syndrome," said Marie-Christine Nizzi. She is a psychology instructor with the Mind, Brain and Behavior Initiative at Harvard University.
"Researchers in this study are cautious but they find that, most of the time, measuring the oxygen in specific areas of the brain allowed them to identify the sentences that patients knew were true versus sentences they knew were false," added Nizzi. She was not involved in the research.
Conditions such as stroke and Lou Gehrig's disease can cause patients to be "locked in," Nizzi said. The formal name for Lou Gehrig's disease, so named because of the legendary baseball player who died from the disease, is amyotrophic lateral sclerosis (ALS).
ALS is a progressive motor neuron disease that destroys the nervous system responsible for movement. In some cases, these patients can communicate by blinking or moving their eyes. But in the most extreme state, they can't control any movement, raising the question of whether they still have the ability to communicate, possibly via brain activity, she said.
In the new study, an international team of researchers worked with four "locked-in" ALS patients. The investigators used an advanced imaging technique and electroencephalography, a measurement of electrical activity, as participants were asked yes-and-no questions. The patients had been trained in how to focus their minds on the answers.
In some cases, the researchers knew the answers to the questions, such as, "You were born in Berlin" or "Your husband's name is Joachim." Others were open-ended, such as questions about whether they had back pain.
The researchers estimated that the patients answered the questions correctly more than 70 percent of the time. ■