Monkeys can now type at a rate of 12 words per minute on a computer using only their minds, according to new research from Stanford University. The scientists hope that this technology might one day help severely paralyzed patients communicate — and they’re currently recruiting patients for a clinical trial to test it out.
Monkeys do not actually know how to read or speak English
Now, monkeys do not actually know how to read or speak English. Nor did they learn how to do so during this particular study. What the two monkeys in the study learned how to do — after a little coaching — was point to dots on a computer screen. The scientists designed a pattern of yellow dots to correspond to a grid of letters, and the dots flashed green in a specific order to spell out text.
The scientists, led by Stanford’s Paul Nuyujukian, previously developed algorithms that translate patterns of brain activity into movement of a cursor on a computer screen. In this study, they wanted to see just how fast these could work. The researchers created a grid of yellow spots, and assigned each spot a letter. They then programmed individual spots to turn green in a sequence that spelled out tracts of text from Hamlet and the New York Times, points of light that guided the monkeys into pressing "letters" in the order they appeared in the original form. Without touching a mouse or keyboard, the monkeys were able to spell out the excerpts letter by letter up to rates of about 12 words per minute. The scientists published their findings today in the journal IEEE.
To connect the monkeys’ brains to the computer, the researchers implanted tiny arrays of electrodes — each array was the size of baby aspirin — into the part of the brain that controls movement. Each time the monkeys started moving their arms to point at a dot flashing green, those arrays would measure the patterns of electrical activity in the nearby brain cells. The monkeys’ arms were tracked by infrared cameras as the animals pointed.
Twelve words per minute is the highest ever brain-based typing rate
Using machine learning, Nuyujukian and his colleagues developed algorithms that linked specific patterns of brain cell activity to the monkeys’ arm movements. Point to the left, one pattern of brain activity. Point to the right, another pattern. With these algorithms, the monkeys could guide a cursor to yellow dots as they flashed green in a predetermined sequence — and fast, too.
Twelve words per minute is the highest ever brain-based typing rate for monkeys, or humans, Nuyujukian says. The speed could be an improvement over current methods that allow people with paralysis to communicate. One of these requires a person to hold up a board with letters, and watch the patient’s eye flicker. Other techniques that use eye movements to select letters can reach speeds of around 46 words per minute, according to a 2012 study in the journal of the Association for Computing Machinery.
The two monkeys in this latest study aren’t an exact model for paralyzed human patients. Both were still able to point with one arm. Keeping the monkeys fully restrained, or temporarily paralyzing them with a nerve block might have been a closer approximation. But monkeys have a tendency to lose interest in a task if they can’t move, and numbing their arms with a nerve block could throw new and confusing variables into the mix, Nuyujukian says. "Clearly no model is perfect, so you go with one that does pretty well," he told The Verge in an email.
Each array was the size of baby aspirin
The monkeys weren’t champion typists by any stretch — twelve words per minute is slower than students’ average touch typing speeds of 72 words per minute. And the monkeys weren’t slowed down by trying to think of what they wanted to say. But, their brain-based typing speeds also weren’t enhanced by autocomplete, either — something the researchers do intend to add to their clinical trials. "You absolutely want to throw the kitchen sink of autocompletion, because you want to maximize that communication rate as much as possible," Nuyujukian says.
Being able to say "I need water" in a fraction of a minute, or to communicate with a loved one using only your mind would be a big leap forward for medicine. But for literature, we’re still where we started — Shakespeare doesn’t have anything to worry about.