Two case studies describing assessment and provision of eye gaze technology for people with severe physical disabilities

Abstract

Eye gaze technology may be beneficial for individuals with little or no movement of their limbs. Examples of such users are those who have suffered brainstem stroke, MS or high‐level quadriplegia (Cook & Hussey, 2002). Its advantage is that it is a direct access method, with no intermediary steps involved in making a selection, thus, potentially speeding access to applications the user requires (eg. communication and environmental control). Using an eye gaze system may also be preferable for those capable of using an indirect method such as a switch accessible scanning interface. Recent advances in the technology, including demands from clinicians, clients and families, raised awareness, and independent evaluation sources such as the COGAIN (communication by gaze interaction) project have stimulated a competitive commercial market for such systems. In the UK, a number of devices are available through different suppliers. It is vital that careful assessment is conducted prior to choosing an gaze interaction system, an example being that a particular system may not accommodate a large amount of involuntary head movement, such as with athetoid CP. The same system however, may be appropriate for someone with a lesser degree of involuntary movement, as found with spinal cord injury. It is therefore important that the assessment process should include careful consideration of the individuals' strengths, identification of goals and tasks, the environment in which they are to be accomplished and identification of assistive technology options (Aigner & Blalock, 1999). This paper presents two case studies; one describes the assessment and provision of eye gaze technology for a young woman born with severe physical disability and the other for an adult with acquired brain injury.