"Locked-in" patients are those who -- despite possessing brain function -- suffer from complete paralyzation. Some of them retain eye movement while others eventually lose this ability and even cease to blink. Their limitations has raised endless questions about their consciousness or even desire to live.

In a bid to address these questions, researchers in Europe developed a brain-computer interface that lets locked-in patients communicate. According to a report from the MIT Technology Review, the team used the machine to successfully communicate with four different patients who lost voluntary movement due to Lou Gehrig's disease (amyotrophic lateral sclerosis). The patients were able to answer "yes" or "no" questions.

This impressive brain-computer interface was developed by neuroscientist Niels Birbaumer from the Wyss Center for Bio and Neuroengineering in Geneva. It's worn over a patient's head much like a swimming cap, measuring electrical waves and blood flow to get answers.

The researchers and the patients underwent about 10 days of testing with statements that they know the answers to, such as "You were born in Berlin" or "Paris is the capital of Germany." The team found that the patients' answers through this communication system were consistent for roughly 70 percent of the time.

More significant statements followed, specifically "I love to live" and "I am happy." Three out of the four participants answered in the affirmative to both questions, while the fourth was not asked these questions due to her parents' concern for her fragile emotional state.

"One patient's family is using it regularly," Birbaumer revealed in a CNN report. "With some training, every caretaker of average intelligence can learn it."

The team is hoping to develop a more comprehensive system in the future so locked-in patients will be able to communicate by selecting letters instead of just yes-or-no statements. The study was published in the journal PLOS Biology.