(RxWiki News) For those with limited mobility in their legs and arms, communicating through the written word or creative expression through drawing is an impossible task. A new technology developed by a French researcher is changing this.
A paper published recently online in Current Biology details a new technology that allows people with movement impairment of the limbs to write using their eyes.
With training, participants were able to write at a rate of about 25 letters per minute.
"Discuss mobility impairment options with your doctor."
The technology allows the user to make smooth eye movements in arbitrary directions using a head-mounted camera and an eye tracker that records eye movements and gaze direction.
The device compensates for erratic and jumpy eye movements with flickering dots that trick the eye into thinking the screen is moving in the same direction as the eyes.
After a brief training of typically three 30 minute session, the user is able to generate digits, letters, words or drawings using the eyes as a pencil.
Jean Lorenceau, PhD, of The National Center for Scientific Research (CNRS) in Paris, France, created and tested the prototype using six participants and himself.
Each testing session consisted of five to ten 30 second runs of continuous eye-drawing recording. Each run was separated by a short period of rest when fatigue and performance assessments took place.
The initial runs included faint colored disks arranged in a ring whose center is locked to eye position. The disks provide real-time feedback to help the participants improve their ability to draw smoothly.
Participants practice without the disks during the second training session and can typically generate smooth eye movements for 5 to 10 seconds at the end.
Unless there is difficulty during the first two sessions, the third session is used to generate digits, letters or small words. Participants blink in between figures, letters, digits and words.
Similar systems currently exist but this is the first to allow the user to trace their own letters with this level of accuracy. This tracing precision is particularly important for drawing signatures.
This new technology can offer easier communication for amputees or those living with neurological conditions like ALS, multiple sclerosis and Parkinson’s disease.
"This is another exciting example of how technology and biology can combine to enhance the lives of patients," says Christopher Quinn, OD, FAAO, of Omni Eye Services in New York and New Jersey. "We have known for some time that eye movements are a trainable skill and this is a unique application of that knowledge."
While this technology is innovative and important, there is still some work to be done. For example, crude segmentation makes it difficult to create such items as the drawing the bar of the letter ‘‘t’’ which requires making a large quick eye movement.
Lorenceau is currently working on improvements to the eye writer and will begin testing an improved version of the eye writer with ALS patients next year.
The project was funded by a grant from the CNRS. No conflicts of interest were reported.