Last month, a paralyzed manusing eye movements. A new technology out of France could allow him not only to type, but to draw and sign his name in cursive on a computer.
The technique, described in the latest issue of the journal Current Biology, relies on a novel head-mounted display that uses a camera to track eye movements and then relays that movement data to a computer.
Discovered by a Paris scientist studying optical illusions, the technique tricks the neuromuscular machinery into overcoming a natural phenomenon known as saccadic eye movements.
Try moving your gaze smoothly across a fixed object. Notice your eyes subtly jumping from one point to another? They're "saccading," a movement that would hinder eye writing in much the same way a shaky hand would interfere with handwriting.
To counteract saccades, Jean Lorenceau of Universite Pierre et Marie Curie-Paris created a temporally modulated visual display with a flickering screen that tricks the brain into thinking the eyes are following a moving object.
"We show that one can gain complete, voluntary control over smooth pursuit eye movements," Lorenceau says. "The discovery also provides a tool to use smooth pursuit eye movements as a pencil to draw, write, or generate a signature."
Lorenceau says it only takes a few brief training sessions to teach subjects to produce legible scripts, such as those pictured, on a computer screen at a rate of 20-30 characters per minute.
Lorenceau is currently working on a better version of his eye writer, and says tests with Lou Gehrig's disease (also known as ALS) patients should start next year.
Of course, there are other potential consumers of this technology, including gamers, and writers, like yours truly, who tend to gesticulate while thinking up their prose.