In recent years, there has been an escalation of orientation and wayfinding technologies and systems for visually impaired people. These technological advancements, however, have not been matched by a suitable investigation of human-computer interaction (e.g. designing navigation aids for people who form different cognitive maps for navigation). The aim of this study is to investigate whether a group of sighted participants and a group of visually impaired participants experience a difference in mental and physical demands when given two different sets of verbal instructions directing them to four landmarks. The content of the first set of instructions was proportioned to route descriptions derived from sighted people, and the second set proportioned to descriptions derived from visually impaired people. The objective assessment involved measuring the time taken by participants to reach landmarks and the number of deviations that occurred. A NASA-Task Load Index questionnaire provided an indication of participants subjective perception of workload. The results revealed that instructions formed from visually impaired people resulted in a lower weighted workload score, less minor deviations, and quicker times for visually impaired participants. In contrast, these instructions were found to cause a higher weighted workload score for sighted participants. The results are discussed in relation to the issue of personalisation of mobile context-aware systems for visually impaired people.
- visual impairment
- information and communications technology
- cognitive maps