Subjective User Experience Research Articles

Controlling Virtual Reality With Brain Signals: State of the Art of Using VR-Based Feedback in Neurofeedback Applications.

The rapid progress of commercial virtual reality (VR) technology, open access to VR development software as well as open-source instructions for creating brain-VR interfaces have increased the number of VR-based neurofeedback (NF) training studies. Controlling a VR environment with brain signals has potential advantages for NF applications. More entertaining, multimodal and adaptive virtual feedback modalities might positively affect subjective user experience and could consequently enhance NF training performance and outcome. Nevertheless, there are certain pitfalls and contraindications that make VR-based NF not suitable for everyone. In the present review, we summarize applications of VR-based NF and discuss positive effects of VR-based NF training as well as contraindications such as cybersickness in VR or age- and sex-related differences. The existing literature implies that VR-based feedback is a promising tool for the improvement of NF training performance. Users generally rate VR-based feedback more positively than traditional 2D feedback, albeit to draw meaningful conclusions and to rule out adverse effects of VR, more research on this topic is necessary. The pace in the development of brain-VR synchronization furthermore necessitates ethical considerations on these technologies.

Usability of the digit-tracking technique in a geriatric population of inpatients with and without neurocognitive disorders: The DIGICOG-start study.

Tools for the early diagnosis of neurocognitive disorders (NCD) both accessible, fast, fun and efficient are currently needed. A digit-tracking technique (Digitrack) has been developed based on the exploration of blurred images on a tablet with the finger, related to the exploration of images during eye-tracking. The present study aimed at assessing the objective usability and the subjective User eXperience (UX) of the Digitrack by older adults according to the presence and the severity of NCD. A total of 135 patients were included in a geriatric acute care unit. Objective usability was assessed through the number of patients able to complete the Digitrack's training (3 images) and evaluation (20 images) phases. UX was measured through standard questionnaires (AttrakDiff and meCUE), and through the description of engagement behaviors following an internally developed scale which included 5 levels (interactive, constructive, active, passive and disengaged behaviors). The success rate of the device was 94.1%. The Digitrack had a very good overall attractiveness, standard hedonic and pragmatic qualities, and the emotions perceived were predominantly positive. These findings were not homogeneously observed in the whole studied population. Patients highly impaired due to NCD tended to rate the device with more neutral scores and to perceive more negative emotions. The participants mainly demonstrated active behaviors, but patients with severe major NCD were mostly passive. The study showed promising results regarding the usability and acceptability of a digit-tracking technique within older adults. Further studies should evaluate the potential of this novel methods to make a cognitive diagnosis.

Luminance-based methodology for assessment of low level haze in glazing

AbstractVisual defects, in particular haze, in glass and façade technologies can significantly impact the aesthetic quality and human experience of daylight and views in buildings. The glass and façade industry increasingly requires methods that can objectively predict and measure the subjective user experience of haze. This is required to appropriately inform the manufacturing process, ensuring optimal functionality and performance, and avoiding material waste and economic losses due to the replacement of defective glazing. Existing methods for measuring haze are not appropriate for assessing large samples, either at manufacturing sites or in-situ. However, haze defects are often only exhibited and visible when glazing is produced in large samples or installed under real luminous conditions. This paper introduces a novel luminance-based method that measures haze by evaluating the halo around a light source that is observed through the glazing. This method is initially tested in a controlled laboratory setting on small glazing samples with varying level of haze. The halo serves as a proxy for haze severity and it is quantified by using luminance-based measurements. In this work, the newly-proposed method is verified by comparing the ranking in haze severity of different samples as performed by means of a standard haze meter and the newly proposed method. Additionally, the paper examines the dependence of this ranking on factors such as camera setup distance and light intensity. It was found that the proposed method was able to effectively ranks samples differing in haze intensity by more than 0.1 orders of magnitude. Positioning the camera closer to the glazing and using higher light intensity yielded more accurate results. However, for haze levels below 1% and differences smaller than 0.1 orders of magnitude, the accuracy is insufficient. To define the expected level of accuracy of methods for haze characterisation in-situ, the sensitivity of the human eye to haze under varying luminous environments and view content needs to be quantified.

A Feasibility Study of HoloLens Ear Image Guidance for Ear Reconstruction.

An ideal 3D cartilage framework and accurate anatomical location are the most important factors to carry out a satisfactory reconstruction of the ear. To streamline this process, we developed an augmented reality assistance system, HoloLens Ear Image Guidance, which is based on computed tomography (CT) data, tailor-made navigation kits to guide reconstruction, data processing software, and HoloLens hardware. The objective of this study is to verify its feasibility in a clinical setting. This study first validated our system in healthy controls and then extrapolated data to test on patients with microtia. First, three healthy volunteers were recruited, and reconstructive navigation kits were made using 3D printing. CT data were collected for the head and neck and imported into the HoloLens Ear Image Guidance Application to generate a personalized 3D virtual ear image. Volunteers then wore the navigation kits while researchers observed them through the HoloLens to check accuracy, track delay, and view the ear image guide.Ten patients with unilateral microtia were recruited and CT data were collected, and reconstructive navigation kits were made to assist with surgery. The procedure was monitored to record the surgeon's experience wearing the HoloLens, the patients' complications associated with wearing navigation kit, and to measure the symmetry between the reconstructed ear and the reference counterpart. In control patients, the deviation between the virtual image and the real ear was less than 2.4% (±0.22%); the tracking delay was less than 1.26 s (±0.09 s), the display effect was good, and surgeons did not report discomfort or dizziness while wearing the HoloLens. Volunteers did not report any pain from holding the navigation reference in their mouth during the test. Following validation, the HoloLens-assisted procedures were not associated with surgeon discomfort or dizziness. No complications were noted in patients including injury to the oral mucosa. Symmetry between the reconstructed ear and the contralateral ear was noted to be satisfactory in HoloLens-assisted surgery. The HoloLens Ear Image Guidance initially met clinical demands in registration accuracy, tracking speed, and subjective user experience, which can be used as the basis for continual software improvements and clinical application.

Privacy-Preserving Gaze Data Streaming in Immersive Interactive Virtual Reality: Robustness and User Experience.

Eye tracking is routinely being incorporated into virtual reality (VR) systems. Prior research has shown that eye tracking data, if exposed, can be used for re-identification attacks [14]. The state of our knowledge about currently existing privacy mechanisms is limited to privacy-utility trade-off curves based on data-centric metrics of utility, such as prediction error, and black-box threat models. We propose that for interactive VR applications, it is essential to consider user-centric notions of utility and a variety of threat models. We develop a methodology to evaluate real-time privacy mechanisms for interactive VR applications that incorporate subjective user experience and task performance metrics. We evaluate selected privacy mechanisms using this methodology and find that re-identification accuracy can be decreased to as low as 14% while maintaining a high usability score and reasonable task performance. Finally, we elucidate three threat scenarios (black-box, black-box with exemplars, and white-box) and assess how well the different privacy mechanisms hold up to these adversarial scenarios. This work advances the state of the art in VR privacy by providing a methodology for end-to-end assessment of the risk of re-identification attacks and potential mitigating solutions. f.

Playing Tetris with Your Mind: A BCI-Controlled Gaming Experience

Brain-Computer Interface Controlled Tetris: Exploring Feasibility and User Experience. This project explores the feasibility and user experience of controlling a Tetris game using a Brain-Computer Interface (BCI). The BCI system utilizes non-invasive Electroencephalography (EEG) to detect P300 brainwaves generated by user focus on specific on-screen cues corresponding to desired game actions (left, right, rotate, drop).An ESP8266 microcontroller board, EEG sensor, and display are used to create a portable BCI system. Software development leverages open-source libraries for EEG signal processing, classification, and game engine control (onboard or external).The experiment evaluates BCI control performance through metrics like accuracy, speed, and Tetris completion rate. A control group playing traditional Tetris (if applicable) allows for comparison. Subjective user experience is assessed through questionnaires and surveys. The results are expected to demonstrate the feasibility of BCI- controlled Tetris using affordable hardware. Potential trade-offs between BCI control speed and traditional methods will be explored. User experience analysis will provide insights into the challenge, enjoyment, and future directions of BCI gaming. This project contributes to the growing field of BCI applications by demonstrating its potential for novel and mind-controlled gaming experiences. Keywords: Brain-Computer Interface, Electroencephalography, performance.

User Experience in Neurofeedback Applications Using AR as Feedback Modality

Neurofeedback (NF) is a brain–computer interface in which users can learn to modulate their own brain activation while receiving real-time feedback thereof. To increase motivation and adherence to training, virtual reality has recently been used as a feedback modality. In the presented study, we focused on the effects of augmented reality (AR) based visual feedback on subjective user experience, including positive/negative affect, cybersickness, flow experience, and experience with the use of this technology, and compared it with a traditional 2D feedback modality. Also, half of the participants got real feedback and the other half got sham feedback. All participants performed one NF training session, in which they tried to increase their sensorimotor rhythm (SMR, 12–15 Hz) over central brain areas. Forty-four participants received conventional 2D visual feedback (moving bars on a conventional computer screen) about real-time changes in SMR activity, while 45 participants received AR feedback (3D virtual flowers grew out of a real pot). The subjective user experience differed in several points between the groups. Participants from the AR group received a tendentially higher flow score, and the AR sham group perceived a tendentially higher feeling of flow than the 2D sham group. Further, participants from the AR group reported a higher technology usability, experienced a higher feeling of control, and perceived themselves as more successful than those from the 2D group. Psychological factors like this are crucial for NF training motivation and success. In the 2D group, participants reported more concern related to their performance, a tendentially higher technology anxiety, and also more physical discomfort. These results show the potential advantage of the use of AR-based feedback in NF applications over traditional feedback modalities.

Interactive Robot Task Learning: Human Teaching Proficiency With Different Feedback Approaches

The deployment of versatile robot systems in diverse environments requires intuitive approaches for humans to flexibly teach them new skills. In our present work, we investigate different user feedback types to teach a real robot a new movement skill. We compare feedback as star ratings on an absolute scale for single roll-outs versus preference-based feedback for pairwise comparisons with respective optimization algorithms (i.e., a variation of co-variance matrix adaptation -evolution strategy (CMA-ES) and random optimization) to teach the robot the game of skill cup-and-ball. In an experimental investigation with users, we investigated the influence of the feedback type on the user experience of interacting with the different interfaces and the performance of the learning systems. While there is no significant difference for the subjective user experience between the conditions, there is a significant difference in learning performance. The preference-based system learned the task quicker, but this did not influence the users’ evaluation of it. In a follow-up study, we confirmed that the difference in learning performance indeed can be attributed to the human users’ performance.

Abstract 12421: Guided Advanced Cardiovascular Life Support Mobile App Improves Trainee Experience and Performance During Simulated Cardiac Arrest: A Randomized Controlled Trial

Introduction: Leading hospital code teams is stressful for resident physicians, and variability in training and experience may result in inconsistent care and outcomes. Nearly all bedside aids like AHA advanced cardiovascular life support (ACLS) pocket cards and third-party ACLS mobile apps lack step-by-step guidance or reminders. Our team designed a guided ACLS mobile app to help trainees lead more effective hospital resuscitations and conducted a randomized controlled trial to assess user experience and performance according to 2020 AHA ACLS guidelines. Hypothesis: A guided ACLS app will improve subjective user experience and adherence to AHA ACLS guidelines. Methods: The ACLS mobile app was developed using Swift UIKit. Internal Medicine, Emergency Medicine, Surgery, and Anesthesia residents (N = 46) were randomized to lead a simulated code for cardiac arrest due to massive pulmonary embolism using either AHA pockets cards (N = 22) or the ACLS app (N = 24). User experience was assessed via surveys. Code outcomes, guideline adherence, and errors were analyzed from video recordings. A focus group of 22 residents provided feedback. Statistical analysis was conducted using R software and included two-sided t-tests and Fisher exact tests. Results: App users showed significantly increased confidence (1.0 vs 0.3; p = 0.005), backboard use (96% vs 27%; p <0.001), end-tidal CO2 monitoring (58% vs 27%; p = 0.042), correct thrombolytic administration (54% vs 23%; p = 0.035), and achieving return of spontaneous circulation (50% vs 18%; p = 0.032) compared to controls. Focus group results showed that 100% of the participants would use the app and that 82% preferred the guided app to AHA pocket cards. Conclusions: The guided app improves user confidence and adherence to AHA ACLS guidelines and addresses the need for greater standardization in hospital code management. Validation studies are necessary to confirm its effectiveness in clinical practice.

The way to generate customer citizenship behavior with customer experience

This study explores the factors that influence customer citizenship behavior in the context of the customer experience of a transportation application that incorporates the concept of the sharing economy. In contrast to previous studies, the research framework of this study predicts customer citizenship behavior through the influence of individual customers' perceptions of product offerings (perceived quality, situational involvement, enduring involvement) on customer experience. Furthermore, considering the nature of the industry where the exchange of services occurs between individual users as both service providers and recipients, this study investigates the moderating effect of communitas. Similarly, this study also addresses how customer citizenship behavior can be encouraged through the elevation of customer experience, facilitated by behavioral engagement. By focusing on the effects of subjective user experiences with the application, this study explores the factors that can encourage customer citizenship behavior. Through this investigation, it aims to propose managerial implications that can enhance the superiority of consumer services.

Exploring the user experience (UX) of a multi-window augmented reality environment

Augmented reality is an emergent form of technology that allows users to interact with and manipulate virtual objects and information integrated into the physical environment. Whether it is replying to browser-based emails or playing a game, completing such tasks in augmented reality requires the use of hand-tracking gestures or interactions. With the anticipated growth of this technology, future users may experience it for extended periods with a variety of applications (e.g., metaverse). This study explores the perceptions and user experience of individuals when interacting with and maneuvering in a multi-window augmented reality environment, using a range of hand-tracking interactions. The results provide both qualitative and quantitative insights into these interactions, highlighting the impact of perceived usability, subjective user experience, perceived difficulty, and perceived workload on task completion.

Usability of curved keyboard design on the large smartphone: An empirical study

The curved design is ubiquitous, with a vast user base due to its similarity with in shape to human physiological structure. The curved QWERTY keyboard layout was proposed for one-handed usage on smartphones with ambiguous effects. This study evaluated whether the curved QWERTY could optimize the user experience and input performance on large smartphones better than the traditional straight QWERTY layout. Eight measurements were used to evaluate the usability of each design, six suggesting curved QWERTY failed to achieve outstanding typing performance or subjective user experience, while the other two indicators showed that curved QWERTY had advantages in touch dispersion and touching offset, indicating the possible higher usability it could reach. The results also investigated the potential application of curved designs and provided insights into the optimization methods.

Utility and Usability of Two Forms of Supplemental Vibrotactile Kinesthetic Feedback for Enhancing Movement Accuracy and Efficiency in Goal-Directed Reaching.

Recent advances in wearable sensors and computing have made possible the development of novel sensory augmentation technologies that promise to enhance human motor performance and quality of life in a wide range of applications. We compared the objective utility and subjective user experience for two biologically inspired ways to encode movement-related information into supplemental feedback for the real-time control of goal-directed reaching in healthy, neurologically intact adults. One encoding scheme mimicked visual feedback encoding by converting real-time hand position in a Cartesian frame of reference into supplemental kinesthetic feedback provided by a vibrotactile display attached to the non-moving arm and hand. The other approach mimicked proprioceptive encoding by providing real-time arm joint angle information via the vibrotactile display. We found that both encoding schemes had objective utility in that after a brief training period, both forms of supplemental feedback promoted improved reach accuracy in the absence of concurrent visual feedback over performance levels achieved using proprioception alone. Cartesian encoding promoted greater reductions in target capture errors in the absence of visual feedback (Cartesian: 59% improvement; Joint Angle: 21% improvement). Accuracy gains promoted by both encoding schemes came at a cost in terms of temporal efficiency; target capture times were considerably longer (1.5 s longer) when reaching with supplemental kinesthetic feedback than without. Furthermore, neither encoding scheme yielded movements that were particularly smooth, although movements made with joint angle encoding were smoother than movements with Cartesian encoding. Participant responses on user experience surveys indicate that both encoding schemes were motivating and that both yielded passable user satisfaction scores. However, only Cartesian endpoint encoding was found to have passable usability; participants felt more competent using Cartesian encoding than joint angle encoding. These results are expected to inform future efforts to develop wearable technology to enhance the accuracy and efficiency of goal-directed actions using continuous supplemental kinesthetic feedback.

Can users embed their user experience in user-generated images? Evidence from JD.com

Nowadays, massive user-generated images (UGIs) are posted online to convey users' experiences with specific brands or products. Thus, this visual information is precious, as it conveys users' actual and subjective feelings about brands and products. Because of the unprecedented quantity of images and the heterogeneity of their content, it is quite challenging for brand marketers and retailers to probe into subjective user experience in large-scale UGIs. To address this gap, this study aims to identify the connection between user experience and different image semantic features (i.e. centrality and richness) by using deep learning models. By employing objective data (8963 images) from JD.com and using deep learning algorithms (faster R-CNN), we found that users with positive user experience prefer to generate high-centrality and high-richness pictures. Our study enriches the relevant literature and provides valuable practical implications for brand marketers and e-commerce retailers. Based on findings of this work, relevant stakeholders can understand their users’ experience better from objective UGIs and devise corresponding recommendation and service strategies.

Engaging learners with games-Insights from functional near-infrared spectroscopy.

The use of game elements in learning tasks is thought to facilitate emotional and behavioral responses as well as learner engagement. So far, however, little is known about the underlying neural mechanisms of game-based learning. In the current study, we added game elements to a number line estimation task assessing fraction understanding and compared brain activation patterns to a non-game-based task version. Forty-one participants performed both task versions in counterbalanced order while frontal brain activation patterns were assessed using near-infrared spectroscopy (within-subject, cross-sectional study design). Additionally, heart rate, subjective user experience, and task performance were recorded. Task performance, mood, flow experience, as well as heart rate did not differ between task versions. However, the game-based task-version was rated as more attractive, stimulating and novel compared to the non-game-based task version. Additionally, completing the game-based task version was associated with stronger activation in frontal brain areas generally involved in emotional and reward processing as well as attentional processes. These results provide new neurofunctional evidence substantiating that game elements in learning tasks seem to facilitate learning through emotional and cognitive engagement.

Patient-reported outcomes for older adults on CamAPS FX closed loop system.

Use of the CamAPS FX hybrid closed loop (CL) system is associated with improved time in range and glycated haemoglobin A1c across the age span, but little is known about its effects on patient-reported outcomes (PROs). This open-label, randomized, multi-site study compared CamAPS FX to sensor-augmented pump (SAP) in a sample of older adults (≥60 years) with type 1 diabetes (T1D). Thirty-five older adults completed PROs surveys at the start of the study and after each period of 16 weeks using either CL or SAP. At the end of the study, 19 participated in interviews about their experiences with CL. Results examining the 16 weeks of CL use showed that the overall Diabetes Distress Scale score and two subscales (powerlessness and physician distress) improved significantly along with trust on the Glucose Monitoring Satisfaction Survey. User experience interview responses were consistent in noting benefits of 'improved glycaemic control' and 'worrying less about diabetes'. In this sample of older adults with T1D who have previously shown glycaemic benefit, there are indicators of improved PROs and subjective user experience benefits.

Methods used to capture subjective user experiences in adults while riding bicycles: a scoping review

ABSTRACT People who ride bicycles often feel unsafe and/or uncomfortable riding in various road conditions. Therefore, understanding the perceptions or experiences of bicyclists in real-world riding conditions is critical to inform interventions that enhance the experience of bike riding and therefore increase participation. A scoping review was undertaken to investigate methods used for capturing subjective experiences in the process of bicycling, or immediately post-ride. Six electronic databases and reference lists of the included studies were searched from inception to May 2021. Of the 11,904 non-duplicate articles, 53 full-text articles were included in the review. The review identified the following methods used to capture the subjective experiences: (i) on-ride method (n = 7), (ii) immediately post-ride method (n = 13), (iii) on-ride plus post-ride methods (n = 8), (iv) ride-along method (n = 4), (v) ride-along plus post-ride methods (n = 6), and (vi) intercept survey methods (n = 15). Some studies exclusively used naturalistic methods for capturing subjective experiences. There is a need to advance methods and standardise approaches to capture subjective user experiences. This is needed to ensure that we are able to understand the experiences and needs of people who ride bikes to inform the provision of safe and connected infrastructure for all ages and abilities.

Development of a customizable interactions questionnaire (CIQ) for evaluating interactions with objects in augmented/virtual reality

As new methods for interacting with systems are being developed for use within augmented or virtual reality, their impact on the quality of the user’s experience needs to be assessed. Although many instruments exist for evaluating the overall user experience or the computer interface used to complete tasks, few provide measures that can be used to evaluate the specific forms of interaction typically used in these environments. This paper describes the development of a customizable questionnaire for measuring the subjective user experience that focuses on the quality of the interactions with objects in augmented reality/virtual reality (AR/VR) worlds, which we are calling the Customizable Interactions Questionnaire, or (CIQ). The final questionnaire measures five factors that are related to user satisfaction while using the system: quality of interactions, assessment of task performance, comfort, quality of sensory enhancements, and consistency with expectations.

Symptom monitoring based on digital data collection during inpatient treatment of schizophrenia spectrum disorders – A feasibility study

Digital acquisition of patients’ self-reports on individual risk factors and symptom severity represents a promising, cost-efficient, and increasingly prevalent approach for standardized data collection in psychiatric clinical routine. Yet, studies investigating digital data collection in patients with a schizophrenia spectrum disorder (PSSDs) are scarce. The objective of this study was to explore the feasibility of digitally acquired self-report assessments of risk and symptom profiles at the time of admission into inpatient treatment in an age-representative sample of hospitalized PSSDs. We investigated the required support, the data entry pace, and the subjective user experience. Findings were compared with those of patients with an affective disorder (PADs). Of 82 PSSDs who were eligible for inclusion, 59.8% (n=49) agreed to participate in the study, of whom 54.2% (n=26) could enter data without any assistance. Inclusion rates, drop-out rates, and subjective experience ratings did not differ between PSSDs and PADs. Patients reported high satisfaction with the assessment. PSSDs required more support and time for the data entry than PADs. Our results indicate that digital data collection is a feasible and well-received method in PSSDs. Future clinical and research efforts on digitized assessments in psychiatry should include PSSDs and offer support to reduce digital exclusion.

Towards Personalized 3D Augmented Reality Windshield Displays in the Context of Automated Driving

As vehicle automation advances, drivers of automated vehicles become more disengaged from the primary driving task. Windshield displays provide a large screen space supporting drivers in non-driving related activities. This article presents user preferences as well as task and safety issues for 3D augmented reality windshield displays in automated driving. Participants of a user study (n = 24) customized two modes of content presentation (multiple content-specific windows vs. one main window), and could freely adjust visual parameters for these content windows using a simulated “ideal” windshield display in a virtual reality driving simulator. We found that user preferences differ with respect to contextual aspects. Additionally, using one main content window resulted in better task performance and lower take-over times, but the subjective user experience was higher for the multi-window user interface. These findings help automotive interface designers to improve experiences in automated vehicles.