Instead of violently shoving a giant needle into the brain a la “The Matrix,” Utah scientists are reading thoughts by carpeting the brain with microelectrodes.
This “modest advance,” as the scientists describe it, could enable more precise control of prosthetic limbs or advance research in epilepsy and other diseases of the brain.
“This was originally developed for epilepsy,” said Bradley Greger, a professor of bioengineering at the University of Utah and co-author of a paper that recently appeared in journal Neurosurgical Focus.
“But this could be really good for neurological control of prosthetic devices.”
There are now three methods to turn brain thought into prosthetic action. Each has positives and negatives. Some devices can be slipped on as easily as hats, but they aren’t specific. The most detailed readings, from even a single neuron, come from threading tiny electrodes deep into the brain, but such operations are risky and very invasive.
While still invasive (the skull must be sawed off), placing electrodes on the surface of the brain instead of inside the brain gives more precise readings while decreasing the risk to patients.
The Utah scientists have so far only placed the microelectrodes in a handful of patients, all of whom suffer from epilepsy. The patients were already scheduled to have a craniotomy to help treat their condition, so they volunteered to have the electrodes placed on their brain during the procedure.
Traditional electrodes are several millimeters in size. The new microelectrodes developed by the Utah scientist are much smaller, so small, in fact, that the 16 microelectrodes were spaced only one millimeter apart from each other on the first patient.
One millimeter was too close however. Each electrode picked up overlapping and confusing signals.
In the second patient, the scientists placed the 32 electrodes two millimeters apart, far enough to more easily detect the electrical signals from the area of the brain that controls arm and hand movements.
“The initial impetus of this development was an even more precise determination of the epileptic focus position and size,” said Kevin Otto, a professor at Purdue University familiar with the research.
“However, as demonstrated by the Utah group, these electrodes can also be used for inputs to brain-machine interface devices.”
The patients, just by thinking about moving their right or left hands and arms, were able to move a computer cursor around a screen. For patients who are paralyzed or suffer from being “locked-in,” or having a functional brain but with no means to move the muscles, it could be a new, albeit intrusive, way to communicate or move.
“If we can give them the ability to communicate at all, that would be great,” said Greger.
Via Discovery.