Recall The Matrix. Neo asks Trinity if she can fly a helicopter. She can't. This has happened to most of us. But then, she makes a phone call to Tank, who uploads the knowledge of helicopter flight directly into her brain.
I tell you this because a researcher at the University of Rochester implied to me that there is a future where this might be possible. They have done nothing like it yet - they have trained monkeys to associate external brain stimulations with activities like pushing a button and spinning a ball. But even teaching the brain things less exciting than helicopter flight could be important for humans.
"Suppose you had a stroke so that you still saw red and green traffic lights. You can still move your leg to step on the accelerator or the brake, but the connections between those things got severed," University of Rochester neurologist Marc Schieber told Gizmodo. "Maybe you can reestablish communication over that link."
The researchers worked with a pair of monkeys trained to operate a silly looking monkey control panel, with buttons, levers and a ball to turn. Initially, the monkey would know to perform a task when blue lights lit up next to it. But the researchers slowly taught the monkeys to associate the lights and tasks with four different, tiny brain stimulations on the premotor cortex. They published the results today in the journal Neuron.
Mazurek and Schieber, Injecting Instructions into Premotor Cortex, Neuron (2017), https://doi.org/10.1016/ j.neuron.2017.11.006
The premotor cortex is a complex part of the brain, one not fully understood, that acts sort of like a processor - it takes inputs from sight and touch and translates it into movement for the motor cortex to execute. In this case, the monkeys eventually learned to associate the stimulation with the task without the light. The researchers could also retrain the monkey to associate the stimulations with different actions.
Humans have poked and prodded plenty of human and monkey brains, Schieber pointed out, and there's still a whole lot to learn. One of the paper's reviewers asked the scientists to ensure that they weren't just invoking muscle responses (they showed that they weren't). But it's hard to say what exactly the monkeys felt. Previous work has shown that stimulating the premotor cortex gave humans a desire to move, even if movement didn't occur. Schieber likened it to knowing to press the gas when you see a green light.
Obviously there's more work to do - this is just two monkeys, after all. The researchers also want to look at whether they can train monkeys based on stimulation in the rest of the brain, and whether stimulation elsewhere would elicit the same response.
But in the long term, the team sees a place they could provide support for stroke victims. "Perhaps you can use existing brain computer interface technology to record upstream from the visual area," explained study author Kevin Mazurek at Rochester, "and use that information to bypass damaged areas of the brain."