That's a problem, because in the human sensory systems, natural stimuli evoke very focal sensory stimulation. "To try to replicate this with large surface electrodes might not be very effective," Normann said.

The Utah Electrode Array is different, designed to be inserted into the brain instead of sitting on its surface. The tips of these microelectrodes sit right next to just a few neurons. When small electrical currents are passed through the electrodes, they stimulate only those few neurons next to the tip.

That should result in two good things, Normann said: "The amount of current needed to stimulate neurons is 100 to 1,000 times smaller than required with surface electrodes, so the Utah Electrode Array should be safer and more biocompatible. These small currents excite only a small number of neurons in the brain, producing focal stimulation." This should produce stimulation closer to normal physiological stimulation.

Still, he said, there's a potential downside. Because the Utah Electrode Array is inserted into the brain or peripheral nervous system (which is home to extensive networks of blood vessels), researchers are working to ensure safety and to verify that they can implant the array into the brain without doing significant damage.

Hear ye, hear ye

Bioengineering researchers at the U. have a contract with the federal government for work with the auditory nerve, as well.

Cochlear implants can restore a sense of hearing to the deaf, but they're not perfect. The level of hearing that's restored with current cochlear implant technology varies. Some hearing-impaired patients hear spoken speech as soon as they turn it on. Many must work at it and practice, practice, practice. Even then, some patients don't do well, though just hearing a sound, like a car horn, can be helpful.

Normann's team is trying to implant the Utah Electrode Array directly into the auditory nerve, something they've been working on for almost three years with colleagues from the U.'s Otolaryngology Department. "We're trying to demonstrate efficacy and safety of what might be regarded as the next generation" cochlear implant.

An unproven but logical theory is that the Utah Electrode Array technology can more selectively stimulate auditory nerve fibers and may result in a higher fidelity restoration of speech, Normann said.

They're also going after the motor system with the Utah Electrode Array.

In certain motor neuron diseases, communication between the brain and the muscles stops and people become "locked in" in their own unresponsive bodies. That happens with ALS, Lou Gehrig's disease. It can also happen with severe high spinal cord injuries.