Artificial Intelligence

The tricky ethics of brain implants and informed consent 


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.”