New Technology Allows Paralyzed People to Write Cursive With Just Their Eyes
New technology designed to allow paralyzed people to communicate by writing cursive with only a look works by teaching the user to overcome the usually jerky movements of eyes.
"Contrary to the current belief, we show that one can gain complete, voluntary control over smooth pursuit eye movements," said Jean Lorenceau of Université Pierre et Marie Curie-Paris. "The discovery also provides a tool to use smooth pursuit eye movements as a pencil to draw, write, or generate a signature."
Like Us on Facebook
Our eyes never stop moving, but it is normally difficult to control these movements in a smooth manner. Instead, the eye will jump from one point to another, called 'saccading'.
Lorenceau stumbled upon the possibilities of smoothly-directed eye movement by chance. While moving his own eyes in front of an optical illusion in his lab, he found that he could see his own eye movement, and with a little practice, he gradually discovered that he could control those eye movements, too.
To steady the gaze, Lorenceau employed an optical illusion called "reverse phi-motion," which uses patterns of contrasting dots on a video screen to create a flickering illusion of motion, reports the Wall Street Journal. The flickering screen tricks the brain into thinking the eyes are following a moving object.
Lorenceau said he can write small words and numbers as fast as he would when writing with his hands, and with practice test subjects were able to produce legible script on a screen at a rate of 20-30 words per minute. They wear a small infrared video camera to transmit their eye movements to the computer.
"It is like drawing with a pencil, but without a tip," he said.
There are other devices that allow users to simply select letters or words from a menu, which may be more efficient, but doesn't allow for personal expression or to indicate subtle differences in meaning.
"Maybe more important is the fact that cursive eye writing provides personal and creative means of expression," Lorenceau told ABC News. "What if the figure you wish to draw is not in this repertoire," he said, "[such as] the drawing of a heart to indicate you love something?"
Lorenceau is now working on a better version of his eye writer, and tests with ALS patients should start next year.
© 2012 iScience Times All rights reserved. Do not reproduce without permission.