A comparison of the psychological effects of robot motion in physical and virtual environments.

A mixed-methods approach was used to assess the fidelity of virtual environments as ergonomic assessment tools for human-robot interaction. Participants performed a visual search task in the physical environment while a nearby collaborative robot repeatedly extended its arm toward them. This scenario was reconstructed in two virtual environments with different levels of graphical detail. Measures of presence, task performance, workload, and anxiety were taken to determine the effect of robot motion in all three environments. Task performance decreased in response to robot motion in the physical environment, while workload and anxiety increased. This simple effect of motion was consistent across environments for measures of task performance and anxiety. However, people performed faster overall in virtual reality, and the effect of motion on workload was greatly reduced in virtual reality. Results in the virtual environments suggest that people were distracted by the sound of the robot, and that presence was affected by manipulations of immersion and coherence.

Task-Oriented and Imitation-Oriented Movements in Virtual Reality Exercise Performance and Design.

OBJECTIVE: This study investigated the influence of game features and practice type on human kinematic and muscular performance in a virtual reality exercise (VRE). Participants demonstrated changes in shoulder flexion angle and muscle activation under different virtual scenarios. BACKGROUND: Conventional VRE studies often compared the outcomes between an experimental group that underwent exercise in VR and a real-world exercise control group, whereas comparisons between VRE programs are lacking. Besides, the attributes of VREs received little attention. METHOD: Thirteen able-bodied participants performed upper extremity exercise movements in immersive VR using a head-mounted display. Participants performed task-oriented and imitation-oriented movements with different game features. Shoulder muscle activity (the deltoid, supraspinatus, and infraspinatus) and shoulder motion were collected. RESULTS: Practice type (task-oriented, imitation-oriented) significantly influenced the flexion angle of the shoulder complex (F(1,11) = 9.53, p = .01), and the muscle activity of the supraspinatus (F(1,9) = 12.61, p = .006) and the infraspinatus (F(1,9) = 12.71, p = .006). Game features did not have a statistically significant effect on shoulder flexion angle or shoulder muscles' activations. CONCLUSIONS: Compared to imitation-oriented practice, task-oriented practice elicited more intensive shoulder movements and muscular efforts but also induced greater movement variations. Substantial differences across game features levels should be further investigated to have significant effects. APPLICATIONS: This research may help guide the design of future VREs. For strength training or rehabilitation where intensive practice is required, task-oriented practice should be considered; for movement learning where movement consistency is required, imitation oriented practice should be adopted.

Examining the Effects of Gender Transfer in Virtual Reality on Implicit Gender Bias.

OBJECTIVE: To investigate the effect of gender transfer in virtual reality on implicit gender bias. BACKGROUND: Gender bias is a type of discrimination based on gender, which can lead to increased self-doubt and decreased self-esteem. Sexual harassment is a hostile form of gender bias that can cause anxiety, depression, and significant mental health issues. Virtual reality (VR) has been employed to help make people become aware of their biases and change their attitudes regarding gender, race, and age. METHODS: Forty participants were embodied in avatars of different genders and experienced sexual harassment scenarios in VR. A gender Implicit Association Test (IAT) was administered before and after the experience. RESULTS: There was a statistically significant main effect of participant gender (F (1,36) = 10.67, p = .002, partial η2 = .23) on ΔIAT, where males and females reported a decrease (M = -.12, SD = .24) and an increase (M = .10, SD = .25) in IAT scores, respectively. A statistically significant two-way interaction between gender transfer and participant gender was revealed (F (1,36) = 6.32, p = .02, partial η2 = .15). There was a significant simple effect of gender transfer for male participants (F (1,36) = 8.70, p = .006, partial η2 = .19). CONCLUSIONS: Implicit gender bias can be modified, at least temporarily, through embodiment in VR. Gender transfer through embodiment while encountering different sexual harassment scenarios helped reduce implicit gender bias. There was a tendency for individuals to increase bias for the gender of the avatar in which they embodied. APPLICATIONS: The current research provided promising evidence that a virtual environment system may be used as a potential training tool to improve implicit gender bias.

Checklists in Healthcare: Operational Improvement of Standards using Safety Engineering - Project CHOISSE - A framework for evaluating the effects of checklists on surgical team culture.

The CHOISSE multi-stage framework for evaluating the effects of electronic checklist applications (e-checklists) on surgical team members' perception of their roles, performance, communication, and understanding of checklists is introduced via a pilot study. A prospective interventional cohort study design was piloted to assess the effectiveness of the framework and the sociotechnical effects of the e-checklist. A Delphi process was used to design the stages of the framework based on literature and expert consensus. The CHOISSE framework was applied to guide the implementation and evaluation of e-checklists on team culture for ten pilot teams across the US over a 24-week period. The pilot results revealed more engagement by surgeons than non-surgeons, and significant increases in surgeons' perception of communication and engagement during surgery with a small sample. Mixed methods analysis of the data and lessons learned were used to identify iterative improvements to the CHOISSE framework and to inform future studies.

Unmet needs and problems related to employment and working as reported by survivors with metastatic breast cancer.

PURPOSE: By 2020, the US population living with metastatic breast cancer (MBC) has exceeded 165,000. A knowledge gap exists regarding the factors affecting work ability for these individuals. We sought to characterize the work status, importance of work, and work-related information needs for women living with MBC. METHODS: We conducted an online survey using an MBC listserv and clinic flyers in 2014-2015. Respondents working at the time of MBC diagnosis were divided into "stably-working" and "no-longer-working" based on employment status at the time of survey. Comparisons were made with chi-square or two-tailed t test. RESULTS: Respondents (n = 133) were predominantly non-Hispanic White (93.2%); 72 were stably-working, while 61 reported no-longer-working. Those no-longer-working were older (54.0 vs 49.5 years old, p < 0.01, Cohen's d = 0.55), further from initial diagnosis of MBC (4.6 vs 3.3 years, p < 0.01, Cohen's d = 0.36), and reported high rates of life interference due to MBC (n = 51, 83.6% vs n = 39, 54.2%, p < 0.01, Cramer's V = 0.32). Stably-working respondents considered work to be important (n = 58, 80.5% vs n = 18, 29.5%, p < 0.01, Cramer's V = 0.57); the top reasons cited were financial and/or insurance (80.4%), importance of staying busy (67.9%), and desire to support themselves and family (64.3%). The stably-working respondents more often valued information on how to talk with employers or co-workers about diagnosis (n = 38, 57.6% vs n = 16, 27.1%; p < 0.01), legal rights in workplace (n = 43, 65.2% vs n = 22, 36.7%; p < 0.01), when to think about stopping work (n = 45, 68.2% vs n = 18, 30%; p < 0.01), and applying for disability (n = 42, 63.6% vs n = 26, 42.6%; p < 0.05), when compared to no-longer-working. CONCLUSION: The decision to stop working may represent a subsequent event driven by cancer progression. This research highlights the ongoing need of information targeting MBC to facilitate the management of employment and financial issues early in the MBC trajectory.

Usage of a Web-Based Workplace and Symptom Self-Management Intervention Tool to Improve Work Ability for Breast Cancer Survivors.

This work aimed to evaluate the usage of a web-based intervention (WISE: Work ability Improvement through Symptom and Ergonomic strategies) developed to improve work ability for women recently diagnosed with breast cancer. Twenty-two women undergoing adjuvant treatment for breast cancer were provided access to WISE. This website includes content pages (e.g., information on ergonomics, symptom management, and other work-related resources) and worksheets (e.g., journals to track symptoms or goals). It could be personalized based on individual work activities and symptoms. Measures assessed at 3 months included usage of the website and perceived usefulness. Thirteen of the 22 participants (60%) accessed WISE; 11 personalized their information. Content and worksheet pages had 97 and 79 visits, respectively. Most frequently visited pages were "setting goals" (i.e., prioritize and track symptoms; 45 visits) and "steps to creating your WISE plan" (i.e., incorporate symptom and ergonomic strategies; 16 visits). Median duration time was 11.05 (range 0.35-79.55) minutes. Usefulness of the content and worksheet pages assessed via a 7-point Likert scale (1 = strongly disagree, 7 = strongly agree) was 5.08 (SD = 1.59) and 4.26 (SD = 2.03), respectively. Participants were likely to recommend WISE to other women undergoing cancer treatment (mean = 6.11; SD = 1.05). The majority of participants personalized WISE work and symptom strategies. Overall, participants agreed that WISE content pages were useful and would recommend WISE for other breast cancer survivors. Results support that majority of breast cancer survivors, undergoing treatment with curative intent, accessed a web-based intervention that provided personalized information on workplace and symptom strategies.

Immersion of virtual reality for rehabilitation - Review.

Virtual reality (VR) shows promise in the application of healthcare and because it presents patients an immersive, often entertaining, approach to accomplish the goal of improvement in performance. Eighteen studies were reviewed to understand human performance and health outcomes after utilizing VR rehabilitation systems. We aimed to understand: (1) the influence of immersion in VR performance and health outcomes; (2) the relationship between enjoyment and potential patient adherence to VR rehabilitation routine; and (3) the influence of haptic feedback on performance in VR. Performance measures including postural stability, navigation task performance, and joint mobility showed varying relations to immersion. Limited data did not allow a solid conclusion between enjoyment and adherence, but patient enjoyment and willingness to participate were reported in care plans that incorporates VR. Finally, different haptic devices such as gloves and controllers provided both strengths and weakness in areas such movement velocity, movement accuracy, and path efficiency.

Using the Microsoft Kinect™ to assess 3-D shoulder kinematics during computer use.

Shoulder joint kinematics has been used as a representative indicator to investigate musculoskeletal symptoms among computer users for office ergonomics studies. The traditional measurement of shoulder kinematics normally requires a laboratory-based motion tracking system which limits the field studies. In the current study, a portable, low cost, and marker-less Microsoft Kinect™ sensor was examined for its feasibility on shoulder kinematics measurement during computer tasks. Eleven healthy participants performed a standardized computer task, and their shoulder kinematics data were measured by a Kinect sensor and a motion tracking system concurrently. The results indicated that placing the Kinect sensor in front of the participants would yielded a more accurate shoulder kinematics measurements then placing the Kinect sensor 15° or 30° to one side. The results also showed that the Kinect sensor had a better estimate on shoulder flexion/extension, compared with shoulder adduction/abduction and shoulder axial rotation. The RMSE of front-placed Kinect sensor on shoulder flexion/extension was less than 10° for both the right and the left shoulder. The measurement error of the front-placed Kinect sensor on the shoulder adduction/abduction was approximately 10° to 15°, and the magnitude of error is proportional to the magnitude of that joint angle. After the calibration, the RMSE on shoulder adduction/abduction were less than 10° based on an independent dataset of 5 additional participants. For shoulder axial rotation, the RMSE of front-placed Kinect sensor ranged between approximately 15° to 30°. The results of the study suggest that the Kinect sensor can provide some insight on shoulder kinematics for improving office ergonomics.

Use of Virtual Reality Feedback for Patients with Chronic Neck Pain and Kinesiophobia.

This study examined how individuals with and without neck pain performed exercises under the influence of altered visual feedback in virtual reality. Chronic neck pain (n=9) and asymptomatic (n=10) individuals were recruited for this cross-sectional study. Participants performed head rotations while receiving programmatically manipulated visual feedback from a head-mounted virtual reality display. The main outcome measure was the control-display gain (ratio between actual head rotation angle and visual rotation angle displayed) recorded at the just-noticeable difference. Actual head rotation angles were measured for different gains. Detection of the manipulated visual feedback was affected by gain. The just-noticeable gain for asymptomatic individuals, below and above unity gain, was 0.903 and 1.159, respectively. Head rotation angle decreased or increased 5.45° for every 0.1 increase or decrease in gain, respectively. The just-noticeable gain for chronic pain individuals, below unity gain, was 0.950. The head rotation angle increased 4.29° for every 0.1 decrease in gain. On average, chronic pain individuals reported that neck rotation was feasible for 84% of the unity gain trials, 66% of the individual just-noticeable difference trials, and 50% of the "nudged" just-noticeable difference trials. This research demonstrated that virtual reality may be useful for promoting the desired outcome of increased range of motion in neck rehabilitation exercises by altering visual feedback.

Use of Virtual Reality Feedback for Patients with Chronic Neck Pain and Kinesiophobia.

This study examined how individuals with and without neck pain performed exercises under the influence of altered visual feedback in virtual reality. Chronic neck pain (n=9) and asymptomatic (n=10) individuals were recruited for this cross-sectional study. Participants performed head rotations while receiving programmatically manipulated visual feedback from a head-mounted virtual reality display. The main outcome measure was the control-display gain (ratio between actual head rotation angle and visual rotation angle displayed) recorded at the just-noticeable difference. Actual head rotation angles were measured for different gains. Detection of the manipulated visual feedback was affected by gain. The just-noticeable gain for asymptomatic individuals, below and above unity gain, was 0.903 and 1.159, respectively. Head rotation angle decreased or increased 5.45° for every 0.1 increase or decrease in gain, respectively. The just-noticeable gain for chronic pain individuals, below unity gain, was 0.950. The head rotation angle increased 4.29° for every 0.1 decrease in gain. On average, chronic pain individuals reported that neck rotation was feasible for 84% of the unity gain trials, 66% of the individual just-noticeable difference trials, and 50% of the "nudged" just-noticeable difference trials. This research demonstrated that virtual reality may be useful for promoting the desired outcome of increased range of motion in neck rehabilitation exercises by altering visual feedback.

Evaluation of older driver head functional range of motion using portable immersive virtual reality.

BACKGROUND: The number of drivers over 65 years of age continues to increase. Although neck rotation range has been identified as a factor associated with self-reported crash history in older drivers, it was not consistently reported as indicators of older driver performance or crashes across previous studies. It is likely that drivers use neck and trunk rotation when driving, and therefore the functional range of motion (ROM) (i.e. overall rotation used during a task) of older drivers should be further examined. OBJECTIVE: Evaluate older driver performance in an immersive virtual reality, simulated, dynamic driving blind spot target detection task. METHODS: A cross-sectional laboratory study recruited twenty-six licensed drivers (14 young between 18 and 35 years, and 12 older between 65 to 75 years) from the local community. Participants were asked to detect targets by performing blind spot check movements while neck and trunk rotation was tracked. Functional ROM, target detection success, and time to detection were analyzed. RESULTS: In addition to neck rotation, older and younger drivers on average rotated their trunks 9.96° and 18.04°, respectively. The younger drivers generally demonstrated 15.6° greater functional ROM (p<.001), were nearly twice as successful in target detection due to target location (p=.008), and had 0.46 s less target detection time (p=.016) than the older drivers. CONCLUSION: Assessing older driver functional ROM may provide more comprehensive assessment of driving ability than neck ROM. Target detection success and time to detection may also be part of the aging process as these measures differed between driver groups.

Virtual exertions: evoking the sense of exerting forces in virtual reality using gestures and muscle activity.

OBJECTIVE: This study was a proof of concept for virtual exertions, a novel method that involves the use of body tracking and electromyography for grasping and moving projections of objects in virtual reality (VR). The user views objects in his or her hands during rehearsed co-contractions of the same agonist-antagonist muscles normally used for the desired activities to suggest exerting forces. BACKGROUND: Unlike physical objects, virtual objects are images and lack mass. There is currently no practical physically demanding way to interact with virtual objects to simulate strenuous activities. METHOD: Eleven participants grasped and lifted similar physical and virtual objects of various weights in an immersive 3-D Cave Automatic Virtual Environment. Muscle activity, localized muscle fatigue, ratings of perceived exertions, and NASA Task Load Index were measured. Additionally, the relationship between levels of immersion (2-D vs. 3-D) was studied. RESULTS: Although the overall magnitude of biceps activity and workload were greater in VR, muscle activity trends and fatigue patterns for varying weights within VR and physical conditions were the same. Perceived exertions for varying weights were not significantly different between VR and physical conditions. CONCLUSIONS: Perceived exertion levels and muscle activity patterns corresponded to the assigned virtual loads, which supported the hypothesis that the method evoked the perception of physical exertions and showed that the method was promising. APPLICATION: Ultimately this approach may offer opportunities for research and training individuals to perform strenuous activities under potentially safer conditions that mimic situations while seeing their own body and hands relative to the scene.

The accuracy of the Oculus Rift virtual reality head-mounted display during cervical spine mobility measurement.

An inertial sensor-embedded virtual reality (VR) head-mounted display, the Oculus Rift (the Rift), monitors head movement so the content displayed can be updated accordingly. While the Rift may have potential use in cervical spine biomechanics studies, its accuracy in terms of cervical spine mobility measurement has not yet been validated. In the current study, a VR environment was designed to guide participants to perform prescribed neck movements. The cervical spine kinematics was measured by both the Rift and a reference motion tracking system. Comparison of the kinematics data between the Rift and the tracking system indicated that the Rift can provide good estimates on full range of motion (from one side to the other side) during the performed task. Because of inertial sensor drifting, the unilateral range of motion (from one side to neutral posture) derived from the Rift is more erroneous. The root-mean-square errors over a 1-min task were within 10° for each rotation axis. The error analysis further indicated that the inertial sensor drifted approximately 6° at the beginning of a trial during the initialization. This needs to be addressed when using the Rift in order to more accurately measure cervical spine kinematics. It is suggested that the front cover of the Rift should be aligned against a vertical plane during its initialization.

Manually locating physical and virtual reality objects.

OBJECTIVE: In this study, we compared how users locate physical and equivalent three-dimensional images of virtual objects in a cave automatic virtual environment (CAVE) using the hand to examine how human performance (accuracy, time, and approach) is affected by object size, location, and distance. BACKGROUND: Virtual reality (VR) offers the promise to flexibly simulate arbitrary environments for studying human performance. Previously, VR researchers primarily considered differences between virtual and physical distance estimation rather than reaching for close-up objects. METHOD: Fourteen participants completed manual targeting tasks that involved reaching for corners on equivalent physical and virtual boxes of three different sizes. Predicted errors were calculated from a geometric model based on user interpupillary distance, eye location, distance from the eyes to the projector screen, and object. RESULTS: Users were 1.64 times less accurate (p < .001) and spent 1.49 times more time (p = .01) targeting virtual versus physical box corners using the hands. Predicted virtual targeting errors were on average 1.53 times (p < .05) greater than the observed errors for farther virtual targets but not significantly different for close-up virtual targets. CONCLUSION: Target size, location, and distance, in addition to binocular disparity, affected virtual object targeting inaccuracy. Observed virtual box inaccuracy was less than predicted for farther locations, suggesting possible influence of cues other than binocular vision. APPLICATION: Human physical interaction with objects in VR for simulation, training, and prototyping involving reaching and manually handling virtual objects in a CAVE are more accurate than predicted when locating farther objects.

Effect of sitting or standing on touch screen performance and touch characteristics.

OBJECTIVE: The aim of this study was to evaluate the effect of sitting and standing on performance and touch characteristics during a digit entry touch screen task in individuals with and without motor-control disabilities. BACKGROUND: Previously, researchers of touch screen design have not considered the effect of posture (sitting vs. standing) on touch screen performance (accuracy and timing) and touch characteristics (force and impulse). METHOD: Participants with motor-control disabilities (n = 15) and without (n = 15) completed a four-digit touch screen number entry task in both sitting and standing postures. Button sizes varied from 10 mm to 30 mm (5-mm increments), and button gap was 3 mm or 5 mm. RESULTS: Participants had more misses and took longer to complete the task during standing for smaller button sizes (< 20 mm). At larger button sizes, performance was similar for both sitting and standing. In general, misses, time to complete task, and touch characteristics were increased for standing. Although disability affected performance (misses and timing), similar trends were observed for both groups across posture and button size. CONCLUSION: Standing affects performance at smaller button sizes (< 20 mm). For participants with and without motor-control disabilities, standing led to greater exerted force and impulse. APPLICATION: Along with interface design considerations, environmental conditions should also be considered to improve touch screen accessibility and usability.

Touch screen performance by individuals with and without motor control disabilities.

Touch technology is becoming more prevalent as functionality improves and cost decreases. Therefore, it is important that this technology is accessible to users with diverse abilities. The objective of this study was to investigate the effects of button and gap size on performance by individuals with varied motor abilities. Participants with (n = 38) and without (n = 15) a motor control disability completed a digit entry task. Button size ranged from 10 to 30 mm and gap size was either 1 or 3 mm. Results indicated that as button size increased, there was a decrease in misses, errors, and time to complete tasks. Performance for the non-disabled group plateaued at button size 20 mm, with minimal, if any gains observed with larger button sizes. In comparison, the disabled group's performance continued to improve as button size increased. Gap size did not affect user performance. These results may help to improve accessibility of touch technology.

Effect of touch screen button size and spacing on touch characteristics of users with and without disabilities.

OBJECTIVE: The aim of this study was to investigate the effect of button size and spacing on touch characteristics (forces, impulses, and dwell times) during a digit entry touch screen task. A secondary objective was to investigate the effect of disability on touch characteristics. BACKGROUND: Touch screens are common in public settings and workplaces. Although research has examined the effect of button size and spacing on performance, the effect on touch characteristics is unknown. METHOD: A total of 52 participants (n = 23, fine motor control disability; n = 14, gross motor control disability; n = 15, no disability) completed a digit entry task. Button sizes varied from 10 mm to 30 mm, and button spacing was 1 mm or 3 mm. RESULTS: Touch characteristics were significantly affected by button size. The exerted peak forces increased 17% between the largest and the smallest buttons, whereas impulses decreased 28%. Compared with the fine motor and nondisabled groups, the gross motor group had greater impulses (98% and 167%, respectively) and dwell times (60% and 129%, respectively). Peak forces were similar for all groups. CONCLUSION: Button size but not spacing influenced touch characteristics during a digit entry task. The gross motor group had significantly greater dwell times and impulses than did the fine motor and nondisabled groups. APPLICATION: Research on touch characteristics, in conjunction with that on user performance, can be used to guide human computer interface design strategies to improve accessibility of touch screen interfaces. Further research is needed to evaluate the effect of the exerted peak forces and impulses on user performance and fatigue.