User Experience In Virtual Environments Research Articles

User Experience in Virtual Environments

User Experience in Virtual Environments

CLASSIFICATION OF COGNITIVE STRESS AS A PSYCHOLOGICAL INDICATOR THROUGH MACHINE LEARNING

In this study, we explored the potential of Support Vector Machine (SVM) method for classifying levels of cognitive stress using EEG (Electroencephalogram) signals. The goal is to develop accurate models that would enable the prediction and understanding of not only the current mental state of the subjects, but also potential real-time interventions. In medical fields, the application can be seen in the treatment of attention, focus, hyperactivity, autism, and depression disorders. Additionally, there is an extremely high potential for application in areas such as psychology, sociology, education, economics, neuromarketing, security, and in enhancing workplace stress management, anxiety treatment, digital marketing, economicfinancial forensics, as well as improving user experience in virtual environments and video games. The results have shown that it is possible to differentiate high and low levels of cognitive stress with satisfactory accuracy, opening the way for the application of these findings in various fields. Cognitive stress represents one of the fundamental cognitive processes that causes individuals to behave and think differently in certain situations than in their usual state of consciousness. Predicting, analyzing, and understanding the level of cognitive stress from EEG signals is of great importance in various fields, including neuroscience, psychology, education, professional sports, human-computer interaction, and many other areas. Machine learning represents a subgroup of artificial intelligence that uses statistical models, and functions to ‘learn’ and ‘train’ data resulting in corresponding output values. The brain-computer interface, through which data on cognitive stress, among other parameters and psychological categories, is collected, is based on the functioning of EEG devices. The prediction of cognitive stress represents the application of machine learning, recording and using brain EEG signals or extracted characteristics from EEG signals as input values, in order to predict the level of output values of cognitive stress, of high or low degree, reflecting the mental state of the subjects in real time

Hand Tracking with Vibrotactile Feedback Enhanced Presence, Engagement, Usability, and Performance in a Virtual Reality Rhythm Game

Recent hand tracking systems and wearable haptic devices have contributed to enhancing user experience in virtual environments. However, controllers are still prevalent in virtual reality (VR) games as a main interaction device. Also, haptic devices are rare and not widely accepted by users. In this article, we examined the effects of interaction methods and vibrotactile feedback on users’ sense of presence, engagement, usability, and task performance in a VR game. In our experiment, 36 participants wearing VR goggle played a rhythm game under three conditions: (1) VR controllers, (2) hand tracking without vibrotactile feedback, and (3) hand tracking with vibrotactile feedback at fingertips through the gloves we developed. Results showed that hand tracking improved presence, engagement, usability, and performance, compared to the VR controller. Furthermore, vibrotactile feedback enhanced presence and engagement even more clearly. Results are discussed with the components of VR user experience and practical design guidelines.

Impact of Different Types of Head-Centric Rest-Frames on VRISE and User Experience in Virtual Environments

This paper presents the results of a user study of the effects of different head-centric rest-frames on Virtual Reality-Induced Symptoms and Effects (VRISE) and the user experience in virtual environments (VE). Participants played the custom-designed 3D game in two different game modes (high action and low action). For assessing VRISE levels, we used the Simulator Sickness Questionnaire (SSQ) and Fast Motion Sickness Score (FMS). The presence was evaluated by SPES (Spatial Presence Experience Scale), and for the user experience, the short version of the User Experience Questionnaire (UEQ-S) was used. The results indicate that the usage of head-centric rest-frames negatively affected VRISE levels (more sickness) in the low action mode of the game. However, for the users experienced with VR technology, the VRISE disorientation symptoms were alleviated in a high action mode of the game with rest-frame glasses. We found no negative effect of rest-frames on the user experience and presence, except for some negative impact when using rest-frame glasses in the low action mode of the game. No negative impact on the performance itself was observed. That means that the usage of head-centric rest-frames is suitable for usage in VR applications. In terms of VRISE levels, we found out that rest-frame glasses are more suitable for the wearers of the distance spectacles, and a baseball hat is more suitable for non-wearers of distance spectacles.

Suitability and Comparison of Questionnaires Assessing Virtual Reality-Induced Symptoms and Effects and User Experience in Virtual Environments.

Although virtual reality (VR) has already achieved technological maturity, there are still some significant drawbacks for technology acceptance and broader user adoption, presenting research challenges. Thus, there is a need for standard, reliable, and quick assessment tools for Virtual Reality-Induced Symptoms and Effects (VRISE) and user experience in VR Assessing VRISE and user experience could be time consuming, especially when using objective physiological measures. In this study, we have reviewed, compared, and performed a suitability assessment of existing standard measures for evaluating VRISE and user experience in VR We have developed a first-person VR game with different scenes and different conditions. For assessing VRISE symptoms, we have used the Simulator Sickness Questionnaire (SSQ) and Fast Motion Sickness Score (FMS). For assessing user experience, we have used the short version of the User Experience Questionnaire (UEQ-S). We have also used a novel Virtual Reality Neuroscience Questionnaire (VRNQ) for assessing VRISE and user experience aspects. The result has shown that FMS and VRNQ (VRISE section) are suitable for quick assessment of VRISE and that VRNQ (User experience section) is suitable for assessing user experience. The advantage of FMS and VRNQ questionnaires is that they are shorter to fulfill and easier to understand. FMS also enables to record the VRISE levels during the virtual experience and thus capturing its trend over time. Another advantage of the VRNQ is that it also provides the minimum and parsimonious cut-offs to appraise the suitability of VR software, which we have confirmed in our study to be adequate.

Immersion and Coherence: Research Agenda and Early Results.

Presence has been studied in the context of virtual environments for nearly thirty years, but the field has yet to reach consensus on even basic issues of definition and measurement, and there are many open research questions. We gather many of these open research questions and systematically group them according to what we believe are five key constructs that inform user experience in virtual environments: immersion, coherence, Place Illusion, Plausibility Illusion, and presence. We also report on the design and results of a study that investigated the effects of immersion and coherence on user experience in a stressful virtual visual cliff environment. In this article, each participant experienced a given VE in one of four conditions chosen from a 2x2 design: high or low levels of immersion and high or low levels of coherence. We collected both questionnaire-based and physiological metrics. Several existing presence questionnaires could not reliably distinguish the effects of immersion from those of coherence. They did, however, indicate that high levels of both together result in higher presence, compared any of the other three conditions. This suggests that "breaks in PI" and "breaks in Psi" belong to a broader category of "breaks in experience," any of which result in a degraded user experience. Participants' heart rates responded markedly differently in the two coherence conditions; no such difference was observed across the immersion conditions. This indicates that a VE that exhibits unusual or confusing behavior can cause stress in a user that affects physiological responses, and that one must take care to eliminate such confusing behaviors if one is using physiological measurement as a proxy for subjective experience in a VE.

Continuous Measurement of Breaks in Presence: Psychophysiology and Orienting Responses

Assessing presence using questionnaires can yield interesting insights into the user experience in virtual environments, but is also limited both in terms of reliability and validity. Breaks in presence (BIPs) are an interesting alternative, given that the researcher can assess them correctly. Prior studies on the psychophysiology of BIPs followed an exploratory approach by not providing a cognitive mechanism for BIPs and lacking in external validity. We argue that BIPs can be considered a special form of orienting responses involving both the real and the virtual world. In the first of the presented studies, we investigated which types of BIPs can be differentiated and to what degree they affect the user experience. In the second study, we modified a commercial video game by introducing the previously identified BIPs and recorded psychophysiological measurements. The results are in line with findings on orienting responses and should provide fertile ground for future research.

Adaptive Generation of Emotional Impact Using Enhanced Virtual Environments

In this paper we introduce novel methods of intensifying and varying the user experience in virtual environments (VE). VEs technically have numerous means for crafting the user experience. Little has yet been done to evaluate those means of expression (MoEs) for their emotional impact on people and to use their capability to create different experiences and subtly guide the user. One of the reasons is that this requires a system which is capable of easily and dynamically providing those MoEs in such a way that they can easily be composed, evaluated, and compared between applications and users. In the following, we first introduce our model of both informational and emotional impact of VEs on users, introduce our dynamic, expressive VR-system, and present our novel evaluation and rating method for MoEs. MoEs can be used to guide attention to specific objects or build up an emotion or mood over time. We then present a study in which users experience 30 selected MoEs and rate their qualitative emotional impact using this rating method. We found that different MoEs can be used to elicit many diverse emotions which were surprisingly consistent among the test persons. With these results, our work enables new ways to make VEs more interesting and emotionally engaging, especially over a longer period of time, opening new possibilities, for example, to increase the motivation for long, stressful, and tiresome training as in neurorehabilitation.

Evaluation for the design of experience in virtual environments: modeling breakdown of interaction and illusion.

New and emerging media technologies have the potential to induce a variety of experiences in users. In this paper, it is argued that the inducement of experience presupposes that users are absorbed in the illusion created by these media. Looking to another successful visual medium, film, this paper borrows from the techniques used in "shaping experience" to hold spectators' attention in the illusion of film, and identifies what breaks the illusion/experience for spectators. This paper focuses on one medium, virtual reality (VR), and advocates a transparent or "invisible style" of interaction. We argue that transparency keeps users in the "flow" of their activities and consequently enhances experience in users. Breakdown in activities breaks the experience and subsequently provides opportunities to identify and analyze potential causes of usability problems. Adopting activity theory, we devise a model of interaction with VR--through consciousness and activity--and introduce the concept of breakdown in illusion. From this, a model of effective interaction with VR is devised and the occurrence of breakdown in interaction and illusion is identified along a continuum of engagement. Evaluation guidelines for the design of experience are proposed and applied to usability problems detected in an empirical study of a head-mounted display (HMD) VR system. This study shows that the guidelines are effective in the evaluation of VR. Finally, we look at the potential experiences that may be induced in users and propose a way to evaluate user experience in virtual environments (VEs) and other new and emerging media.