An update to this story was published September 28, 2019, noting that the researchers who conducted this work were found to have committed scientific misconduct by two investigations.

Patients with complete “locked-in syndrome”—conscious, but fully paralyzed and unable to move even their eyes—may soon be able to mentally break out.

Using a new, noninvasive device that measures brain waves and blood flow, four locked-in patients were able to communicate by answering yes or no questions, neuroscientists report this week in PLOS Biology. The four patients, all completely paralyzed by Lou Gehrig’s disease, or amyotrophic lateral sclerosis (ALS), answered geography questions, correctly identified family members’ names, and even said they were happy and glad to be alive.

The study’s lead author, neuroscientist Niels Birbaumer, of the Wyss Center for Bio and Neuroengineering in Geneva, told MIT Technology Review that “the relief was enormous” for the families after hearing the positive responses.

ALS is a progressive neurodegenerative disease that destroys nerve cells in the brain and spinal cord that are responsible for movement. As it advances, patients lose the ability to breathe and even move their eyes. If patients accept being on artificial ventilation, they stay alive while being completely cut off from communicating with the outside world.

Researchers have been trying to figure out ways to get back in touch with them for years. In 1999, Birbaumer and colleagues found that a brain-computer interface helped an ALS patient who still had eye movement to communicate. And other researchers have developed methods to translate blood flow and electrical waves from the minds of locked in patients who also still had some movement. But the methods hadn’t been able to unlock the minds of those with no movement left.

The researchers created a cap with both near-infrared spectroscopy (NIRS) and electroencephalography (EEG) to measure changes in blood oxygen levels and electrical activity in the brain. Then, the researchers used their brain-computer interface to decipher what a “yes” response looks like and what a “no” response looks like for each patient. To train and test the technique, the researchers asked questions such as “Paris is the capital of Germany,” and “Your husband’s name is Joachim.”

The patterns were consistent about 70 percent of the time. And the researchers moved on to open-ended questions, including “You have back pain,” “I love to live,” and “I rarely feel sad.”

Of the four patients, all of whom had been completely locked in for years, three said they were happy and loved to live. The fourth, a 24-year-old woman who had rapid onset of the disease, was not asked because her parents feared she was in a delicate mental state, MIT Technology Review reports.

One patient was asked if he would give his blessing for his daughter to marry her boyfriend. He repeatedly responded “no.”

The researchers say the results need to be verified in more patients. However, they’re hopeful that the technology will help treat and monitor locked-in patients, as well as allow them to regain some quality of life.

PLOS Biology, 2017. DOI: 10.1371/journal.pbio.1002593 (About DOIs).