Planet of the Geeks

In a development that raises new hopes for people who have suffered strokes and spinal cord injuries, monkeys that were taught to play a computer game were able to overcome wrist paralysis with an experimental device that enabled them to use the paralyzed muscles via the activity of a single brain cell.

(I hasten to add that the paralysis was induced with anesthesia and was temporary.)

The monkeys were taught to play a computer game that involved moving a cursor to a target. They had a hand placed on a flat surface and learned to control the cursor's movements by pressing down with their palm or up with the back of their hand.

A probe had been placed in each animal's brain to monitor the firing of a single brain cell. After the hand was anesthetized, the firing of the cell was used to send electrical stimulation to that monkey's wrist muscles.

This method of generating movement is known as functional electrical stimulation, or FES.

Partially paralyzed people use FES devices now to let them stand, walk, use their arms and hands, and do other things. But they control those devices by flicking a switch, moving joints or tensing a muscle - even, say, the muscle that enables them to wiggle an ear.

But such options are limited for, for example, quadriplegics, who have comparatively few muscles they can control. The point here is that the monkeys quickly learned to control the firing rate of that brain cell to direct the movements of their hands and continue playing the game. The researchers even found that the device could use brain cells that normally had nothing to do with wrist movement.

So a large untapped pool of brain cells may be available for letting paralyzed people do things like grasping a coffee cup or brushing teeth, [study co-author Chet] Moritz said.

Dawn Taylor of Case Western Reserve University in Cleveland, who studies the concept of using brain signals to overcome paralysis, called the results "an important step forward."

On the other hand, of course, even such simple things as holding a cup or brushing your teeth are a good deal more complex than merely moving a hand up or down and would require considerably more complex monitoring of a good number of brain cells - and would then depend on the brain's ability to coordinate all those signals. That's hardly out of the question: Simply walking requires a good deal of muscular coordination by the brain so that it won't be said of us "he's no fun, he fell right over."

But the truth remains that "the approach is years, if not decades, away from use in people" according to Moritz.

"There's a long ways to go, and there's no way to say with confidence that it will work," Moritz said. ...

Andrew Schwartz of the University of Pittsburgh, who has used brain signals to enable monkeys to control robot arms, said he considered the new work a modest advance, noting hurdles that remain.

But that's just a bunch of buzzkill and for now, instead of contemplating the hurdles, I'm going to contemplate the vision of quadriplegics someday running the hurdles.