V. Kathlene Emery

Older adults and visual impairment: what do exposure times and accuracy tell us about performance gains associated with multimodal feedback?

This study examines the effects of multimodal feedback on the performance of older adults with different visual abilities. Older adults possessing normal vision (n=29) and those who have been diagnosed with Age-Related Macular Degeneration (n=30) performed a series of drag-and-drop tasks under varying forms of feedback. User performance was assessed with measures of feedback exposure times and accuracy. Results indicated that for some cases, non-visual (e.g. auditory or haptic) and multimodal (bi- and trimodal) feedback forms demonstrated significant performance gains over the visual feedback form, for both AMD and normally sighted users. In addition to visual acuity, effects of manual dexterity and computer experience are considered.

Toward achieving universal usability for older adults through multimodal feedback

This experiment examines the effect of combinations of feedback (auditory, haptic, and/or visual) on the performance of older adults completing a drag-and-drop computer task. Participants completed a series of drag-and-drop tasks under each of seven feedback conditions (3 unimodal, 3 bimodal, 1 trimodal). Performance was assessed using measures of efficiency and accuracy. For analyses of results, participants were grouped based on their level of computer experience. All users performed well under auditory-haptic bimodal feedback and experienced users responded well to all multimodal feedback. Based on performance benefits for older adults seen in this experiment, future research should extend investigations to effectively integrate multimodal feedback into GUI interfaces in order to improve usability for this growing and diverse user group.

The effects of multimodal feedback on older adults' task performance given varying levels of computer experience

This experiment examines the effect that computer experience and various combinations of feedback (auditory, haptic, and/or visual) have on the performance of older adults completing a drag-and-drop task on a computer. Participants were divided into three computer experience groups, based on their frequency of use and breadth of computer knowledge. Each participant completed a series of drag-and-drop tasks under each of seven feedback conditions (three unimodal, three bimodal, one trimodal). Performance was assessed using measures of efficiency and accuracy. Experienced users responded well to all multimodal feedback while users without experience responded well to auditory-haptic bimodal, but poorly to haptic-visual bimodal feedback. Based on performance benefits for older adults seen in this experiment, future research should extend investigations to effectively integrate multimodal feedback into GUI interfaces in order to improve usability for this growing and diverse user group.

Foundation for improved interaction by individuals with visual impairments through multimodal feedback

Abstract.Through an investigation of how the performance of people who have normal visual capabilities is affected by unimodal, bimodal, and trimodal feedback, this research establishes a foundation for presenting effective feedback to enhance the performance of individuals who have visual impairments. Interfaces that employ multiple feedback modalities, such as auditory, haptic, and visual, can enhance user performance for individuals with barriers limiting one or more channels of perception, such as a visual impairment. Results obtained demonstrate the effects of different feedback combinations on mental workload, accuracy, and performance time. Future, similar studies focused on participants with visual impairments will be grounded in this work.

Multimodal feedback: establishing a performance baseline for improved access by individuals with visual impairments

Multimodal interfaces have the potential to enhance a users overall performance, especially when one perceptual channel, such as vision, is compromised. This research investigated how unimodal, bimodal, and trimodal feedback affected the performance of fully sighted users. Limited research exists that investigates how fully sighted users react to multimodal feedback forms, and to-date even less research is available that has investigated how users with visual impairments respond to multiple forms of feedback. A complex direct manipulation task, consisting of a series search and selection drag-and-drop subtasks, was evaluated in this study. The multiple forms of feedback investigated were auditory, haptic and visual. Each form of feedback was tested alone and in combination. User performance was assessed through measures of workload time. Workload was measured objectively and subjectively, through the physiological measure of pupil diameter and a portion of the NASA Task Load Index (TLX) workload survey, respectively. Time was captured by a measure of how long it took to complete a particular element of the task. The results demonstrate that multimodal feedback improves the performance of fully sighted users and offers great potential to users with visual impairments. As a result, this study serves as a baseline to drive the research and development of effective feedback combinations to enhance performance for individuals with visual impairments.

Isolating the effects of visual impairment: exploring the effect of AMD on the utility of multimodal feedback

This study examines the effects of multimodal feedback on the performance of older adults with an ocular disease, Age-Related Macular Degeneration (AMD), when completing a simple computer-based task. Visually healthy older users (n = 6) and older users with AMD (n = 6) performed a series of drag-and-drop tasks that incorporated a variety of different feedback modalities. The user groups were equivalent with respect to traditional visual function metrics and measured subject cofactors, aside from the presence or absence of AMD. Results indicate that users with AMD exhibited decreased performance, with respect to required feedback exposure time. Some non-visual and multimodal feedback forms show potential as solutions to enhance performance, for those with AMD as well as for visually healthy older adults.

Strategic design for users with diabetic retinopathy: factors influencing performance in a menu-selection task

This paper examines factors that affect performance of a basic menu selection task by users who are visually healthy and users with Diabetic Retinopathy (DR) in order to inform better interface design. Interface characteristics such as multimodal feedback, Windows® accessibility settings, and menu item location were investigated. Analyses of Variance (ANOVA) were employed to examine the effects of interface features on task performance. Linear regression was used to further examine and model various contextual factors that influenced task performance. Results indicated that Windows® accessibility settings significantly improved performance of participants with more progressed DR. Additionally, other factors, including age, computer experience, visual acuity, and menu location were significant predictors of the time required for subjects to complete the task.