The tricky ethics of brain implants and informed consent

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

This week I covered some exciting new research. Two teams reported that they used brain-computer interfaces to help people who had lost their ability to speak regain their voice. Each group used a different kind of implant to capture electrical signals coming from the brain, and a computer to translate those signals into speech.

The participant in the first study, Pat Bennett, lost her ability to speak as a result of ALS, also known as Lou Gehrig’s disease, a devastating illness that affects all the nerves of the body. Eventually it leads to near-total paralysis, so even though people can think and reason, they have almost no way to communicate.

The other study involved a 47-year-old woman named Ann Johnson, who lost her voice as the result of a brain-stem stroke that left her paralyzed, unable to speak or type.

Both these women can communicate without an implant. Bennett uses a computer to type. Johnson uses an eye-tracking device to select letters on a computer screen or, often with her husband’s help, a letterboard to spell out words. Both methods are slow, topping out at about 14 or 15 words a minute, but they work.

That ability to communicate is what gave them the power to consent to participate in these trials. But how does consent work when communication is more difficult? For this week’s newsletter, let’s take a look at the ethics of communication and consent in scientific studies where the people who need these technologies most have the least ability to make their thoughts and feelings known.

People who especially stand to benefit from this type of research are those with locked-in syndrome (LIS), who are conscious but almost entirely paralyzed, without the ability to move or speak. Some can communicate with eye-tracking devices, blinks, or muscle twitches.

Jean-Dominique Bauby, for example, suffered a brain-stem stroke and could communicate only by blinking his left eye. Still, he managed to author a book by mentally composing passages and then dictating them one letter at a time as an assistant recited the alphabet over and over again.

That kind of communication is exhausting, however, for both the patient and the person assisting. It also robs these individuals of their privacy. “You have to completely depend on other people to ask you questions,” says Nick Ramsey, a neuroscientist at the University Medical Center Utrecht Brain Center in the Netherlands. “Whatever you want to do, it’s never private. There’s always someone else even when you want to communicate with your family.”

A brain-computer interface that translates electrical signals from the brain into text or speech in real time would restore that privacy and give patients the chance to engage in conversation on their own terms. But allowing researchers to install a brain implant as part of a clinical trial is not a decision that should be taken lightly. Neurosurgery and implant placement come with a risk of seizures, bleeding, infections, and more. And in many trials, the implant is not designed to be permanent. That’s something Edward Chang, a neurosurgeon at UCSF, and his team try to make clear to potential participants. “This is a time-limited trial,” he says. “Participants are fully informed that after a number of years, the implant may be removed.”

Making sure trial participants give informed consent is always important, but communication struggles make the process tricky.

Ramsey’s group has been working with patients with ALS for years, and they’re one of a few teams working with patients who have extremely limited communication abilities. In 2016, they reported that they had developed a system that allowed a woman with ALS to use her mind to perform a mouse click. By the end of the study, she could select three letters per minute. “That person has used it for seven years, and she used it day and night to communicate when she couldn’t use any other means anymore,” he says. Now, Ramsey and his colleagues are working with other individuals in an attempt to translate brain activity into speech.

The consent process is “a pretty elaborate procedure,” Ramsey says. First, the team explains the research in detail more than once. Then they ask a set of 20 simple yes-or-no questions to make sure the individual understands what the research will entail. There’s a limit to how many questions the potential participant can get wrong. All this happens in the presence of a legal guardian and an independent observer, and the whole procedure is recorded on video, Ramsey says. The process takes about four hours, and that doesn’t include the several weeks that patients have to mull over their decision.

But people who are dependent on others for their care and communication needs are in a particularly vulnerable spot. In one paper, researchers point out that the desire to consent might be influenced by how a patient’s decision would affect family members and caregivers. “If an implantable BCI trial or therapy offers the prospect of changing the character or degree of dependency on others, a [person with ALS] may feel obligated to pursue a BCI. Depending on the nature of this felt obligation, the voluntariness of the decision to have a BCI implanted may come into question.”

Ramsey’s group doesn’t work with patients who are completely locked in, unable to communicate via any voluntary movement or noise. But he says there are potentially ways to get consent with the help of a functional MRI scanner. “They have to perform a simple task like reading words or counting backwards,” he says. “Simple tasks that we know work in everyone who is awake.” If the data shows the person isn’t performing those activities, the researchers assume that “either the person is not able to follow instructions or the person doesn’t want to participate and tells us so by deliberately not doing the task.”

But that’s still theoretical. Putting brain implants in people who have the most extreme version of locked-in syndrome is generally frowned upon, Ramsey says.

“There are clear legal and ethical rules for engaging people who can not express themselves in BCI research,” he says. “It is very hard to justify an implant in complete LIS, even if a legal guardian consents.” In a study published last year, scientists reported that a man who was fully locked in could communicate with the help of a brain implant by changing his brain activity to match certain tones. But in this case, the man gave consent for the procedure before he entirely lost the ability to communicate.

At least for now, people already in a locked-in state are stuck. A brain-computer interface might be their only hope of communicating, but they’re excluded from studies because they can’t convey their desire to join. As technology advances and therapies emerge, some of those people might regain their voice. That’s why finding ethical ways for them to provide informed consent is a goal worth pursuing. Indeed, some scientists say it’s a moral imperative.

From around the web

A bit of good news heading into the fall. The FDA approved the new RSV vaccine for pregnant women, and they may be able to get the shot as soon as October (NBC News).

People with long covid can experience health problems that last at least two years, according to a new study in Nature Medicine. The research, which relies on health records from the Department of Veterans Affairs, suggests that people who had even mild covid-19 early in the pandemic have a higher risk of lung problems, diabetes, and other health issues two years out than people who didn’t contract the virus then. (Washington Post).

This long and weird history of the new raft of weight-loss drugs includes a Gila monster. They work, but scientists still don’t know why. (New York Times)

Covid is ticking up this fall. But experts don’t see it settling into a seasonal pattern just yet. (Stat News)