The technology, which uses the microelectrodes to convert the thoughts of amputees and paralyzed people into signals that control artificial body parts, is expected within a few years at the earliest. Further research and fine tuning on the computer software is being done to possibly interpret brain signals resulting in actual movement of a prosthetic limb.

The findings are not the first in the realm of microelectrodes being placed on the surface of the brain. A Massachusetts study explored similar technologies, but U. researchers expanded the array of electrodes to include 100 brain readers, making them smaller and able to read larger surface areas of the brain, Kellis said. He said he's astounded at the impact a single processing unit can have in a person's life.

Newer, smaller versions can detect many of the discrete nerve impulses that control body movements. The spacing of the microelectrodes is also critical.

The nonpenetrating electrodes may allow a longer life for devices that will help disabled people use their own thoughts to control computers, robotic limbs or other machines. The longer lifespan has yet to be proven, "but we are very optimistic that by being less invasive, it certainly should last longer and provide a more durable interface with the brain," House said.

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