An Investigation into Accessible Web Navigation for the Blind People

Current screen-reader program used by the blind people to access the Internet inflicts navigation restrictions since the blind users can only perceive the content in serial mode. The serialized access using screen-reader program restricts the blind users from having the multi-dimensional effects required to fully understand the page layout. We believe that by accessing web pages using bi-modal interaction, a blind user would be able to perceive a two-dimensional perspective of a web page in his or her mental model. The purpose of this study is to investigate the differences in the mental models created by blind people from a two-dimensional web page using two different means: one using a screen-reader only and the other using a touch screen with audio feedback. Ten blind people and thirty sighted blindfolded participants participated in this study. This study employed within-subjects repeated measures experiments together with observations, verbal protocols and semi-structured questionnaires to achieve the objectives of the study. Besides, the influence of user’s spatial ability on the user’s performance was investigated using Tactual Performance Test (TPT). The study revealed that using touch screen with audio feedback; the blind people achieved more accurate orientation. However, the accuracy seems to be affected by page complexity. In addition, investigation of blind users’ spatial ability on users’ sense of position revealed that using touch screen with audio feedback, blind participants with lower spatial ability took longer time to locate information. Therefore, users’ spatial ability plays an important determinant for the Web navigability using touch screen with audio feedback.