Page 148 - Handbook of Electronic Assistive Technology

136 HANDBOOK OF ELECTRONIC ASSISTIVE TECHNOLOGY

Assessment
Learning to use eye-gaze requires time, practice and patience and eye-gaze-enabled
resources and activities are claimed to offer a motivating and engaging route to develop-
32
ing eye-gaze skills. Examples include Look to Learn and the Inclusive Eye-gaze Learning
33
Curve. Some eye-gaze systems track and record the user’s gaze and so provide educa-
tionalists and clinicians with objective data that can give insights into visual and cognitive
skills, as well as preferences and motivation.

Selection Set Design for Eye-gaze

Eye-gaze access requires some unique considerations for the design of applications and
selection sets. Compared to other methods of access that are commonly employed by users
with complex physical needs, such as head-operated mice, joysticks or switches, eye-gaze
may be faster and physically less demanding. Some users may find it hard to accurately
target small items on screen and one solution is to create ‘2 hit’ selection sets composed
of fewer items, with larger targets, linked together. The user chooses a group of items, then
with the second ‘hit’ the required item. ‘2 hit’ selection sets take advantage of the speed of
access of eye-gaze while allowing for less accurate targeting.

Michael’s Case Study

Michael is 6 years old and has quadriplegic cerebral palsy. He has been using eye-gaze to access
his communication aid since he was four and is now an expert. At first, he used a symbol-
based vocabulary, but now he generates his language with a letter keyboard and prediction.
He also accesses digital books and learning resources, and uses his device for writing in school.

Malcolm’s Case Study
Malcolm is now 14 years old and has been using a joystick to access an on-screen keyboard
since he was 4 years old. He has evaluated eye-gaze on at least three separate occasions,
and the two most recent trials which were undertaken with representatives of the resellers
were extremely positive. However, Malcolm’s experience when evaluating the technology
for an extended trial prior to purchase was less successful and he did not feel that eye-gaze
offered a practical method of access. The reasons for this lack of success may be more
related to support, context and the environment than the eye-gaze technology itself.

Switch Access

Switches and switch access systems have a long history for providing access to assistive
technologies, dating from the earliest examples of electronic assistive technologies such

32 Look to Learn eye-gaze activities: https://thinksmartbox.com/product/look-to-learn/.
33 Inclusive Eye Gaze Learning Curve: http://www.inclusive.co.uk/inclusive-eye-gaze-learning-curve.