Sooner or later, it seems, most everything imagined in science fiction comes true. From flying in space to talking on a telephone without wires, today's science increasingly resembles yesterday's fiction. And that's becoming more and more true in medicine.

For those of us at the AAAS meeting, nothing was more impressive than the demonstration given by Jennifer French. She's not a scientist. She's a young woman sitting in a wheelchair, paralyzed from a snowboarding accident. She presses a button on a control box strapped to her waist ... and then she stands up.

"So here you see the functional benefit and the fact that I can stand out of my wheelchair," she explained. "I can reach for things I usually can't reach. I can move around into spaces where the wheelchair wouldn't fit. And I can transfer onto spaces that I normally wouldn't be able to transfer onto."

In the case of a spinal cord injury like Jennifer French's, the leg muscles, for example, aren't damaged. They just don't receive a signal from the brain telling them what to do. The system developed by Hunter Peckham and colleagues at Case Western Reserve University bypasses the injured part of the nervous system and applies an electrical stimulation to replicate the signal that the muscles no longer receive. But the artificial system takes some getting used to.

"There is a distinct learning curve," French explained. "Because when ...[you] press the button, there's a three-second delay, you stand and there's another three-second delay, where it's fully implanted so you have to get your timing down of how it works. And that's what you really need to work on, because there is a learning curve."