(CBS News) There's been an astounding development in a story we first brought you on '60 Minutes." Researchers are reporting that a woman who is completely paralyzed has used a robotic arm controlled with nothing but her thoughts.
It's a triumph of neurobiology and computer science you have to see to believe as CBS Evening News anchor Scott Pelley found out when we first met the woman, Cathy Hutchinson, in 2008.
It had been 11 years since a stroke left Cathy Hutchinson paralyzed from the neck down, unable to speak, but completely aware. A sensor with 100 electrodes was surgically placed on her brain to pick up the electrical signals brains create when we think about movement. The sensor was wired to a computer through a connection bolted to her skull.
John Donoghue, at Brown University, developed the system after decoding some of the brain's electrical language.
"If you look at this square, each one of these little black boxes is the electrical signal coming from one electrode in the brain," Donoghue said, demonstrating the technology.
And how well do we understand this language?
"We know that there's a general pattern of, for example, left-right, up-down, even fast or slow," he said.
Four years ago, Dr. Leigh Hochberg of Massachusetts General Hospital, explained as Hutchinson moved the computer cursor with her thoughts.
"We're seeing Cathy moving this cursor with nothing but her mind?" Pelley asked.
"She's thinking about the movement of her hand, and she's moving the cursor much as if she had her hand on a mouse," Hochberg said.
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Hochberg asked Hutchinson if she wanted to put on some music.
And seconds later, she did just that -- moving the cursor across the screen and clicking "play."
Now, four years later, in the study published Wednesday in the journal "Nature," researchers report Hutchinson has gone even further -- controlling a robotic arm with her mind.
"She was able to reach and grab any ball in any location about half the time, which to us was remarkable that she could do any of that," Donoghue said.
Once they proved it worked, they wanted to see whether the technology could one day change her life.
"So we said, 'Ok, you can now have your morning coffee but you're going to serve yourself for the first time in almost 15 years,'" Donoghue recounted. "When she reached out and grabbed the cup we were all breathless. No one was moving. No one was doing anything."
"To be able to watch her reach out and pick that up, and to see the smile on her face as soon as she did that was a magical moment for all of us," Hochberg said.
A lot of research is being done in this area to create robotic limbs for people suffering with paralysis and for troops who've lost arms and legs. After more than five years, Cathy Hutchinson has been disconnected from the computer, as planned. But she's let the researchers know she'd like to continue helping in their work.
Below, watch video from the Brown Institute for Brain Science showing Hutchinson operating the arm:
