Brain implant allows paralyzed man to communicate, says study

Story Transcript

Researchers say a man who is paralyzed by amyotrophic lateral sclerosis (ALS) was able to communicate with them, thanks to brain implants that can register the man's neural signals.

According to the researchers, the study is the first evidence of being able to communicate with someone who is in a completely "locked-in" state, and unable to speak or move their eyes.

"For his family and for everybody on the team, it was very emotional as well as satisfying that we enabled someone to express themselves and to express their wishes and desires," Ujwal Chaudhary, one of the researchers, formerly from the University of Tübingen in Germany, told As It Happens guest host Gillian Findlay. "This was, I would say, very fulfilling as a researcher and also as a human being."

The study was published this week in the journal Nature Communications.

While many are optimistic about the study, others say that the results should be taken with caution. Neil Thakur, chief mission officer of the ALS Association, told the New York Times, "This approach is experimental, so there's still a lot we need to learn."

'A brain implant might be a solution'

The man was diagnosed with ALS in August 2015, when he was 30 years old. ALS is a rare degenerative disease that affects nerve cells in the brain that control the ability to move. It's also known as Lou Gehrig's disease.

By the end of 2015, the patient lost his ability to speak and walk, and has needed a ventilator to help him breathe since July of 2016. 

During that time, his sight was still strong enough to use eye-tracking technology to select letters and write sentences on a computer screen. But after a year, he was no longer able to hold his gaze steady enough for the eye-tracker to work.

His family members looked for another way to reach him, by using a manual approach. They held up a sheet of paper with a grid of letters on it, and if they saw any eye movement from him while they pointed to a particular letter, they'd interpret it as a 'yes.' 

But the patient knew he would eventually lose control of his ability to move his eyes, which led to his family contacting the University of Tübingen researchers in December 2017. A few months later, Chaudhary met the man.

"We saw that the patient could still move his eyes and with that eye movement, the family always tried to decipher his yes and no answer in response to their questions," Chaudhary said.

"I saw this interaction and designed a brain-computer interface based on his eye movement for communication. But from our past experience, we knew that in the case of ALS, the disorder progresses to a point where the patient is unable to use even his eyes. So we proposed to the patient's family, in that case, a brain implant might be a solution."

"We explained it to the patient's family and to the patient himself," the researcher said. "With his eye movement, he consented to the implantation process."

Training the mind

Once the researchers implanted the device inside the man's brain, they had to teach him how to use it to communicate.

"Initially we instructed him to imagine or attempt a different kind of motor movement, like move your hand, move your feet, move your tongue and things like that," Chaudhary said. "Although we observed brain signals … [in] response to these tasks, it was not consistent enough to design a decoder to allow him to spell."

After 12 weeks of trying that approach, they decided to try a neurofeedback system to give the man more tools to decode his movements himself. This meant showing the man his brain activity in real time, so that he could learn how to control his eyes movements and match them to sound waves. 

"What happens is that every block started with a target tone, either of high frequency... or low frequency ... followed by a sound wave which the patient had to modulate. That is, increase or decrease the frequency of sound tone to match to the target tone," Chaudhary explained.

In other words, if he wanted to say 'yes', he attempted to move his eyes and produced one kind of brain signal. When he wanted to say no, he didn't move his eyes and instead produced another kind of brain signal. 

Once the man started saying 'yes' and 'no' to letters, he could form words and then sentences.

I'm sure that he was able to express himself and express his love for his family, that they are taking care of him…. It improved his quality of life.​​​​​​- Researcher Ujwal Chaudhary 

"The first sentence was, he wanted the caretaker to position his head in a particular position," Chaudhary recalled. "We enabled him to instruct people how to take care of him."

One researcher told the New York Times that more work needs to be done, as the study is based on just one patient.

Chaudhary and fellow researcher Neils Birbaumer had two earlier studies retracted after a German Research Foundation investigation. The researchers disagree with the investigation's findings and Birbaumer sued the foundation. A verdict is expected soon.

Minding his words

Ever since the man learned to use his brain implant, Chaudhary said he has communicated several needs, including wanting a new bed, soup and even for music to played in the background.

"I was with the patient's family for a long time, sometimes til midnight … and he used to say, 'Beer,' and then we used to drink beer in the end," the researcher laughed.

The man also has young children — and the researcher believes that the device has changed his relationship with them.

"He got to say things to his son, like, 'I have dinosaurs for you, I have a car for you," Chaudhary said.

"Then to his mom and to [his] wife and sister, he said 'Thanks for taking care of him.'

"I'm sure that he was able to express himself and express his love for his family, that they are taking care of him…. It improved his quality of life."

Written by Mehek Mazhar. Interview with Ujwal Chaudhary produced by Morgan Passi.