Text Entry via Character Stroke Disambiguation for an Adolescent With Severe Motor Impairment and Cortical Visual Impairment

Abstract

This study proposed a single-switch text entry system by hierarchical scanning of character strokes for an 11-year-old girl with severe physical disabilities and low vision. She could only perceive magnified straight line segments and chords presented against high-contrast, colored backgrounds. In a descriptive case study, the participant used the proposed system in the community for 8 months. Assessment included theoretical evaluation of text entry performance and empirical evaluation of the participant's proficiency. The proposed system had a lower error-free text entry rate but comparable proneness to user error as a real-world implementation of row-column virtual scanning keyboard with character frequency layout. The participant's proficiency, in terms of mean number of single-switch activations and time to type one character, showed statistically significant improvements as the case study progressed. The proposed system feasibly addressed the participant's typing needs, in a context where traditional row-column scanning and codeword-based text entry systems were not successful.

Benefits of the use of ICT in school activities by students with motor, speech, visual, and hearing impairment: A literature review

“…The focuses of five studies were product development (56)(57)(58)(59)(60). In these studies new types of devices and software, e.g.…”

“…The remaining 15 studies were divided equally into students with speech impairment (51-53, 68, 69) (Table IV), students with visual impairment (56,58,59,65,70) ( Table V) and finally, students with hearing impairment (40,41,54,55,60) (Table VI).…”

“…The outcome in studies related to visual impairment indicated ( Table V) that all new products holds promise (56,58,59), e.g. provided a functional text-entry solution for students with low vision (59), even if the students had comments on the design of the products.…”

“…In two studies new ICT items were tested with the purpose of making graphical elements in maths accessible (56,58). In addition, an access solution system (single-switch text-entry system) was investigated to enable a student with visual impairment and severe motor impairment to use the computer for writing (59). The special maths software (56), the Talking Tactile Tablet (58) and an advanced text-entry solution (59) were newly available devices and the students' performances were measured with and without the new products.…”

Data input and content exploration in scenarios with restrictions

“…The most minimalist techniques assume the use of a single switch, which can be activated by a button [Belatar and Poirier, 2008;Leung et al, 2010], a headband sensor [Mackenzie and Felzer, 2010], or any intentional muscle contraction. These techniques are based on the principle of a scanning keyboard, in which letters or groups of letters are highlighted sequentially and the entry is made using a series of selections to narrow in on and select the desired letter [Mackenzie and Felzer, 2010].…”