Matthew M. Brehmer

Abstract: Cognitive Testing on a Computer (C-TOC) is a self-administered web-based computerised cognitive assessment battery. C-TOC's intended scenario of use involves an older adult, who has presented a concern regarding his or her cognitive health, completing the test independently at home, as directed by their family physician or a specialty clinic.

This thesis presents the results of two studies aimed to address the viability of older adults completing the C-TOC test battery in a home setting, first to identify usability issues, and second to understand the effects of interruptions on C-TOC performance. In Study 1, an initial standard evaluation of C-TOC's usability was conducted with representative users and a cross-cultural advisory panel of health professionals. Based on our own observations of participants' interactions with C-TOC, together with subjective reporting measures (interviews, questionnaires, & focus group discussion), several user interface design issues were identified. Given these issues, this thesis presents a list of recommendations for improving C-TOC's usability in subsequent versions.

The bulk of the novel contributions presented in this thesis arise from Study 2. In this study, we report the findings of a laboratory experiment to investigate the effects of increasingly demanding interrupting tasks on older adults' C-TOC testing performance. Related work has reported interruptions having a range of inhibitory and facilitatory effects on primary task performance. Cognitive ageing literature has suggested that increased interruption workload demand should have greater detrimental effects on older adults' performance, when compared to younger adults.

With 36 participants from 3 age groups (19-54, 55-69, and 70+), we found divergent effects of increased interruption demand on two primary tasks. Results suggest that older and younger adults experience interruptions differently, that increased interruption demand can incur a task resumption cost. However, at no age is test performance, in terms of accuracy, compromised by demanding interruptions. This finding is reassuring with respect to the success of C-TOC, and is promising for other applications used by older adults.

It is our hope that what was learned from both studies will contribute to the development of a usable and valid cognitive assessment test.

Abstract: The usability of a visual interface is largely dependent on the extent to which visual perceptual mechanisms are supported. This report investigates the design of a visual interface, identifying interface elements that are both optimally and poorly designed, with respect to perceptual mechanisms. Recommendations, grounded in an understanding of these mechanisms, are offered to improve the visual design of the interface.

Abstract: Haptic icons are short sequences of vibrations designed to provide meaningful information and feedback to the user. In order for the icons to be useful, strategies to help users to identify, distinguish, and recall them need to be developed. In this paper, we investigate the effect that naming haptic icons has on the accuracy with which users are able to identify, distinguish, and recall the icons. We have conducted a between-subjects experiment using 60 participants equally divided in three naming conditions: no names, pre-selected non-descriptive names, and self-selected names. The experiment examined the impact that different naming strategies had on the ability of participants to accurately match the icons to given stimuli as well as their ability to remember the names. Our results suggest that while many participants felt that the names were useful, naming did not actually have any significant impact on the accuracy with which users were able to match icons to targets. Additionally, participants reported that allowing them to choose the names for the icons enabled them to better remember and distinguish the icons than participants who were presented with icons given non-descriptive names. Despite this finding, the groups did not differ significantly in their ability to remember the icons.

Abstract: This project report documents a design study in the domain of organic agriculture, and presents Informed Omnivore, an exploratory analysis tool for visualizing the Canadian organic food industry. A goal of this application is to provide consumers with the information necessary to make informed choices when buying local or organic food. I provide an overview of the domain, task, and data addressed by the application, followed by a description of the information visualization solution. This is followed by an analysis of the solution's strengths and weaknesses. This report concludes with a discussion of potential areas for future work. The contribution of Informed Omnivore is a demonstration of information visualization techniques applied to domain of organic agriculture, motivating casual users to make sustainable and healthy food choices.

Abstract: This project describes the design of Walkabout; a persuasive mobile application that aims to motivate its users to walk. The design addresses this goal by providing users easy access to knowledge about popular places for walking and by increasing their motivation to walk through leveraging their social network. If we are to consider the increasing ubiquity of mobile devices and their location-aware capabilities, we can be confident that our design is feasible. In this paper, a mixed horizontal/vertical medium fidelity prototype, which is based on initial low-fidelity prototypes, is presented along with a formal evaluation process and results. In addition, we present evidence indicating that our mobile application design is likely to have positive long-term effects on users' walking habits.

Source: GAIM Developer Documentation:

Many active games are developed around specific hardware platforms, such as accelerometers, camera input, or pedal and steering input. Stach and Graham reviewed 114 active games for the purpose of classifying input techniques found throughout these games, abstracted away from the input hardware. Previous analogous classifications have been carried out for traditional input techniques (mouse, keyboard) and tabletop computing. Hardware-independent input includes power, pointing, stance, gestures, tap, and continuous control. These can be used in conjunction with traditional input (mouse, keyboard, gamepad, or a joystick). Many existing hardware-dependent games could make use of alternative hardware should they make use of a toolkit which abstracts input type from the hardware device being used. This would allow game developers to focus on game content and story rather than low-level input peripherals. This would also make games more portable and allow for people with different hardware to play together.

Input can be abstracted from specific devices in two stages. Device-specific data can be abstracted to the level of which the data's origin could be from one of many devices in the same class. The data is then again abstracted to the level of input techniques, which could employ a variety of device classes.

At the device level, input data from individual devices is collected, implementing the interfaces described at the abstract device level. An example of which is the Tunturi E6R, which implements the IBike and IHRMonitor interfaces, providing properties such as power wattage generated and current heart rate. The device level is a thin layer above any available proprietary 3rd party or existing APIs for enabled devices.

The abstract device level refers to broad classes of input devices, or devices with a substantial amount shared functionality. These include exercise equipment (bikes, treadmills, etc.), accelerometers, cameras, exertion or resistance devices, pads, and mats. For example, Bike input can refer to many instances of exercise bicycle hardware devices, such as the Tunturi E6R or the FitXF PCGamerBike Mini. Camera input can represent input from standard webcams, Sony Eyetoy cameras, or Project Natal input.

The input level refers to the high-level hardware-independent or abstract input in active games. This level of input includes the aforementioned input types: gesture, stance, pointing, power, continuous control, and tap.

The GAIM framework is written in Visual C# / XNA Studio 3.0, allowing for easy integration with existing XNA-based games.

Abstract: Exercise video games encourage people to be more physically active by combining entertainment and physical movement. On the other hand, conventional sedentary video games attract players with challenging mental tasks and puzzles. We address the question as to how performance on such tasks is effected by physical movement when they are placed in the context of an exercise video game.

Sports psychology research suggests a general improvement in cognitive task performance during and after physical activity. To assess if these findings can be replicated in the domain of exercise video games, we present an experiment in which we monitor the performance of game players on text comprehension, reaction time, and virtual target shooting tasks while cycling for several minutes on a recumbent bicycle. Our results suggest that the former two tasks are unaffected by exercise intensity, while the ability to perform the latter task is hampered under higher levels of exercise intensity.

Abstract: Research on contextual cueing with real-world scenes has demonstrated that the location of task-relevant visual information can be predicted from a stable visual context, and that scene-target associations are explicitly encoded in memory. In addition, observers are biased to associate target locations in naturalistic scenes with global contexts. Less acknowledged is the possibility that observers with domain-specific expertise may form these associations differently than non-experts for scenes representative of their domain. This study contrasts the role of global and local contexts in contextual cueing for domain-specific scenes. Go board configurations serve as the domain, as their meaningfulness depends on an observer's knowledge of the game.

Abstract: This report will document the results of a musical instrument building project, in which I have built a guitar-mounted kalimba, or thumb piano. I will also discuss the construction of a second instrument, a regular wood-mounted kalimba, which in many ways improves upon its guitar-mounted counterpart.