Claudia Mitchell is the first "bionic woman."
When Mitchell thinks, "close your hand," her hand closes, even though she lost her hand and entire arm two years ago.
Mitchell, a 26-year-old former Marine, lost her left arm in a motorcycle accident in 2004 and just received a bionic prosthesis from the Rehabilitation Institute of Chicago.
She now has partial use of the arm that she lost -- and she controls it with her thoughts.
Mitchell follows Jesse Sullivan, a former Tennessee power lineman who was the first male to receive this type of prosthetic arm in 2002.
Four other men have become bionic with this type of arm since Sullivan.
The device is revolutionary because it is controlled by the person's brain, say the prosthesis' developers.
For Mitchell, it is revolutionary because she now has part of her life back.
"What I had before was very frustrating," Mitchell said, referring to a previous artificial arm.
"Now I can do many of the daily activities I was unable to do following my injury, like pick up a cup, open a jar, and peel a banana."
The Science of the Bionics
How exactly does Mitchell do those activities?
Surgeons move nerves from the shoulder -- nerves that used to be attached to the arm -- and reconnect them to skin and muscles in the chest.
After those nerves are in place, the brain still thinks they are attached to the missing arm.
When Mitchell thinks about moving her arm, special sensors that have been placed over the rerouted nerves pick up the signals from the nerves and muscles, translating them into movement in the artificial arm.
The arm moves with the help of the former shoulder nerves that are now attached to the chest muscles.
The nerves rerouted to the skin of the chest let Mitchell feel what her prosthetic arm feels, including hot and cold sensations.
The rewiring does not happen overnight, though.
"It takes about three [months] to five months from the time of surgery for the nerves to grow in," said Dr. Todd Kuiken, director of the Neural Engineering Center for Artificial Limbs and Center for Bionic Medicine at the Chicago institute.
Kuiken led the team that developed the bionic arm with support from the National Institutes of Health.
A New Lease on an Arm
For Mitchell, who now can use her bionic arm to pick up objects, eat, and dress, her long journey has been worth it.
"People don't know how lucky they are until faced with the difficulties of losing an arm," she said.
The current version of the prosthesis has three motors located within the prosthetic arm that work together to carry out commands.
Future models will use six motors. The goal is to produce more natural movements and allow recipients to perform more complex tasks.
Scientists hope that this technology will eventually lead to even more functional models, including legs through which the person can actually feel where they are walking.
Mitchell is trying to give a little bit back, because she has been given a sort of second chance with her arm.
She currently serves as a mentor for new Marine officers and as an active supporter to other amputees returning from Afghanistan and Iraq.