New method allows for indirect signal capture

Jun 29, 2009 07:27 GMT  ·  By
University of Utah Neurosurgeon Paul A. House, shown here in an operating room
   University of Utah Neurosurgeon Paul A. House, shown here in an operating room

For amputees and paralysis victims, harnessing the power of brain impulses to control bionic limbs is about the only chance of getting at least some functions back in, or instead of, their paralyzed arms and legs. Until now, this was only possible by installing hair-thin electrodes in the brain, and by “in” we mean deep inside the cortex. A new method, now devised by experts at the University of Utah, allows for neuron readings to be made without using poking senors.

Rather, it makes use of a network of sensors placed over the cortex, but which does not penetrate it. According to the team behind the new system, the method is just as effective as any other, but it has the advantage of being non-intrusive, and causing less potential damage to the cortex.

“The unique thing about this technology is that it provides lots of information out of the brain without having to put the electrodes into the brain. That lets neurosurgeons put this device under the skull but over brain areas where it would be risky to place penetrating electrodes: areas that control speech, memory and other cognitive functions,” UU Assistant Professor of Bioengineering Bradley Greger explains.

He is also the co-author of a new study detailing the finds, scheduled for online publication in the July 1st issue of the journal Neurosurgical Focus. The expert says that, in the near future, the effects of diseases such as spinal injury, stroke, and Lou Gehrig's disease on the brain's speech centers may be overridden with the new technology, which will pass the electrical impulses of the brain area into a computer that would then vocalize the thoughts in audible words.

For amputees and paralysis victims, “this device should allow a high level of control over a prosthetic limb or computer interface. It will enable amputees or people with severe paralysis to interact with their environment using a prosthetic arm or a computer interface that decodes signals from the brain,” Greger says.

The expert notes that durability is one of the main issues plaguing such a system. “If you're going to have your skull opened up, would you like something put in that is going to last three years or 10 years?” he asks. “No one has proven that this technology will last longer. But we are very optimistic that by being less invasive, it certainly should last longer and provide a more durable interface with the brain,” the lead author of the new study, University of Utah Neurosurgeon Paul A. House, concludes.