SSS 2010-01-19（在线收听）

Most of us blink without thinking. But people who’ve sustained strokes or combat injuries can lose their ability to blink. Which is important for lubricating and cleaning the eye. Surgery is an option—a small piece of muscle transplanted from the leg can sometimes work. But the operation takes 10 hours and has its own dangers. So scientists at the University of California, Davis, Medical Center are developing artificial muscles to help patients blink again, work discussed in the Archives of Facial Plastic Surgery.

The blink system starts with what researchers call an eyelid sling, a small piece of muscle or fabric that holds the eyelid. The sling attaches to bone around the eye. It’s then linked to an electrostatic polymer—basically a piece of flexible plastic that expands or contracts via voltage change. A tiny battery hidden in a natural hollow in the temple powers the polymer. Electrical current keeps the muscles contracted and the eyes open. Kill the current and the lid closes.

Here’s the creepy part—the mechanism’s been tested on cadavers, which are blinking away. But now that the principle is proven, in the next years real patients could be on the brink of a blink.

—Cynthia Graber