CONTEXT

How disabled people having lost the motor control of their limbs but still having a good control of their eye-movements can communicate? Several solutions relying on eye movements have been investigated. Current devices mainly rely on sequences of Saccade/Fixation/Selection that allow choosing amongst items displayed on a computer screen. These solutions are however often slow, produce fatigue and discomfort, strongly constrain observer’s behavior, offer a restricted list of what is possible or not and do not result in a personalized and emotionally rich communication. None of these devices attempted to exploit all capabilities of eye movement control and expression, in particular the smooth pursuit eye-movements that human observers easily perform when following a moving target, or the information carried by the modulation of pupil size.

TECHNICAL DESCRIPTION

In the present work, Dr Lorenceau has developped a device comprising an eye-tracker to record eye movements as well as pupil size coupled to a specific visual display. The whole device is driven by a software in charge of controlling the visual display parameters, in calibrating the eye-tracker and in recording eye movements. The visual display which acts as a stimulus is at the core of the present invention and allows the operator to produce and direct smooth pursuit eye-movements at will after a short period of training. With this device, smooth eye-pursuit is directed by the user, recorded anddisplayed on screen. After training, smooth patterns corresponding to internal visuo‐motor representations can be easily generated to produce smooth line-drawings of letters, numbers or written words on-line in an easy and fast way.

DEVELOPMENT STAGE

• A prototype has been sucessfully developped.
• Numerous developments are currently investigated:

– using pupil size to modulate the expressivity of the eye traces;
– improving the training protocol to quickly and efficiently master directed smooth pursuit;
– testing patients with visual or oculo-motor deseases (e.g. Glaucoma, DMLA, dyspaxia);
– coupling eye-movements to different devices: a plotter to draw on line,  sound system to make music or any device able to control external devices using directed pursuit (e.g. robots, domotics, joystick, etc.).

BENEFITS

Directed smooth pursuit eye-movement allowed by the device offers numerous advantages compared to existing devices:

• Fast communication;
• Fast and easy training and using;
• Personnalized and emotionally rich way of communication and expression

INDUSTRIAL APPLICATIONS

The present device not only aims at restoring writing capacities through the recording of smooth pursuit eye movements for disabled people who can still control their eyes but also at enhancing this function in healthy persons for research purpose (eye-movement modelling, plasiticity of brain function), educational purpose (learning to read and write) or artistic purpose (music, drawing…).

For further information, please contact us (Ref 04319-01)