Physically real and virtual reality exposed line bisection response patterns: visuospatial attention allocation in virtual reality.

Dissociation between visual line bisection and mental number line bisection in schizophrenia

The performance levels of human subjects in size identification and size discrimination experiments in both real and virtual environments are presented. The virtual environments are displayed with a PHANToM desktop three degree-of-freedom haptic interface. Results indicate that performance of the size identification and size discrimination tasks in the virtual environment is comparable to that in the real environment, implying that the haptic device does a good job of simulating reality for these tasks. Additionally, performance in the virtual environment was measured at below maximum machine performance levels for two machine parameters. The tabulated scores for the perception tasks in a sub-optimal virtual environment were found to be comparable to that in the real environment, supporting previous claims that haptic interface hardware may be able to convey, for these perceptual tasks, sufficient perceptual information to the user with relatively low levels of machine quality in terms of the following parameters: maximum endpoint force and maximum virtual surface stiffness. Results are comparable to those found for similar experiments conducted with other haptic interface hardware, further supporting this claim. Finally, it was found that varying maximum output force and virtual surface stiffness simultaneously does not have a compounding effect that significantly affects performance for size discrimination tasks.

Extended-Reality Technologies: An Overview of Emerging Applications in Medical Education and Clinical Care.

Validation of immersive virtual reality line and baguette bisection tasks for the assessment of unilateral spatial neglect.

Virtual reality (VR) enables the study of visually-guided behavior in situations that are otherwise not amenable to laboratory research. An example is a fire evacuation scenario, in which building occupants have to find their way to safety through smoke and flames, identify safe egress routes, and avoid threats. First, however, it must be determined whether evacuation behavior in VR is comparable to that in a real environment. We are thus initially studying participant responses to a fire alarm in matched virtual and real environments. The present experiment investigates how the decision to evacuate is influenced by visual cues about a neighbor’s behavior. In the Control group, a lone participant is exposed to a fire alarm while performing a bogus task. In the Passive group, a participant performs the same task with a confederate who ignores the fire alarm. In the Active group, the confederate immediately leaves the room when the fire alarm sounds. The gender of the participant is crossed with the gender of the confederate. 75 participants experience the scenario in a real environment (25 per group), and 75 others in a matched virtual environment presented in a wireless head mounted display (HMD), with avatars of the confederates. In the real environment, two-thirds of participants in the Control group evacuated the room. In the Active group, nearly all did so, whereas in the Passive group all but one did. More female than male participants evacuated in the Control group, but there were no other gender effects. Data collection in the virtual environment is in progress, and will be completed by spring. The findings thus far demonstrate a very strong influence of neighbor behavior on a participant’s evacuation decision. The results will provide answers to the much-debated question of whether evacuation behavior is similar in virtual and real environments. Meeting abstract presented at VSS 2015

Perception of safe robot idle time in virtual reality and real industrial environments

The virtual reality Walking Corsi Test

Objective:The prism adaptation (PA) with rightward shifting lenses is a promising rehabilitation technique for left hemispatial neglect. The PA has also been applied in healthy individuals to investigate cognitive mechanism(s) underlining such adaptation. Importantly, studies have suggested that PA may primarily impact the functions of the dorsal or the ventral attentional stream, and we have previously reported that PA to the upward and downward shifting lenses leads to a significant aftereffect in vertical line bisection task. However, this post-adaptation effect, similarly to that seen in the horizontal plane, might have been modified by the presence of the vertical pseudoneglect healthy participants often experience prior to PA. Thus, the aim of this study was to test this hypothesis.Participants and Methods:30 right-handed healthy adults (age M=22,4) performed a computerized line bisection (LB) in vertical and horizontal condition. The bisections were performed twice: before and after PA procedure. Participants took experimental procedure three times, each in at least 24 h of break, each time in one of three conditions of shifting lenses; down, up, control. Both LB tasks (vertical and horizontal) consisted of 24 lines, each centered on 23" touch screen. The participants were asked to find the middle of the line. Throughout the experiment, participants were comfortably seated with their head positioned on a chinrest. Participants were fitted with prismatic goggles that deviated their visual field by 10 degrees. For the adaptation we used the Peg-the-mole procedure consisting of 120 pointing movements.Results:To assess the effect of the vertical PA on landmark judgments we performed a repeated measures ANOVA with direction of PA (upward/downward), the condition of LB (vertical/ horizontal) and pre- vs post adaptation as a between-subjects factor. This analysis revealed a main effect of the direction of PA (p< 0.001) and a main effect of condition (p< 0.001). Overall, however, only adaptation in up-shifting lenses led to significant aftereffects (p<0.05). Further, when we excluded participants who did not exhibited horizontal pseudoneglect in preadaptation LB, the effect of PA in downshifting PA emerged in vertical LB (p<0.05). Further, this group also exhibited the aftereffect of PA in up-shifting lenses for the horizontal (p<0.01) and the vertical LB (p<0.05). Additionally, these participants exhibited a congruent tendency after upward and downward PA, and tended to allocate their attention more upward and rightward.Conclusions:The results of this study confirm that the vertical PA evokes a visuo-spatial bias. Moreover, the PA aftereffect seems to be modified by the presence of the pre-adaptation pseudoneglect. Whereas the mechanism inducing this bias is not fully known, it might be explained in light of the interhemispheric activation-inhibition balance. Both the upward and downward PA may primarily lead to activation of the posterior regions of the right hemisphere, and this activation may result with the upward and rightward bias in the LB task. However, future research with neuroimaging techniques is needed to test this hypothesis.

This paper adresses the issue of properly designing a digital mock-up (DMU) to be used in an experiment comparing simulated assembly tasks in both real and virtual environments. Motivations and specifications relative to the experiment are reported, and the design process of the DMU is described and illustrated. Recommendations are proposed with a particular focus on specificities relative to the use of a DMU as a support for both manufacturing and virtual reality—3D visualisation and interaction. A subjective evaluation of Real (RE), Virtual (VE), and Virtual with Force Feedback (VEF) environments is provided. Results indicate a real sensory and difficulty gap between RE and VEF, whereas a smaller difference was observed between RE and VE. In further improvements of scale-1 (where the objects in VE have the same size as in the real environment), co-localized simulation using haptic devices are warranted to fill in this gap. Results also highlight the impact of cognition and sensory feedback on user’s feeling and presence sensation. Applications of such numerical designs are presented in the last section, especially focusing on collaborative design sessions. Virtual Reality based evaluation of newly designed workstations will be a way in the future to improve design and user learning processes.

Although the human brain is adapted to function within three-dimensional environments, conventional laboratory research commonly investigates cognitive mechanisms in a reductionist approach using two-dimensional stimuli. However, findings regarding mnemonic processes indicate that realistic experiences in Virtual Reality (VR) are stored in richer and more intertwined engrams than those obtained from the conventional laboratory. Our study aimed to further investigate the generalizability of laboratory findings and to differentiate whether the processes underlying memory formation differ between VR and the conventional laboratory already in early encoding stages. Therefore, we investigated the Repetition Suppression (RS) effect as a correlate of the earliest instance of mnemonic processes under conventional laboratory conditions and in a realistic virtual environment. Analyses of event-related potentials (ERPs) indicate that the ERP deflections at several electrode clusters were lower in VR compared to the PC condition. These results indicate an optimized distribution of cognitive resources in realistic contexts. The typical RS effect was replicated under both conditions at most electrode clusters for a late time window. Additionally, a specific RS effect was found in VR at anterior electrodes for a later time window, indicating more extensive encoding processes in VR compared to the laboratory. Specifically, electrotomographic results (VARETA) indicate multimodal integration involving a broad cortical network and higher cognitive processes during the encoding of realistic objects. Our data suggest that object perception under realistic conditions, in contrast to the conventional laboratory, requires multisensory integration involving an interconnected functional system, facilitating the formation of intertwined memory traces in realistic environments.

BackgroundEmerging new technologies may lead to the discovery of new treatment techniques in psychiatric disorders. Virtual Reality (VR) is being one of the newly developed techniques that has also taken its place in literature very recently. VR is a new technology for treatment of psychiatric symptoms. This is a pilot study that aims to determine the behavioral and symptomatic response of patients to a real recorded VR environment. In this study, a virtual reality laboratory has been established and a psychosocial treatment program through virtual reality has been developed for patients with schizophrenia. The aim of this study is to investigate the effect of VR psychosocial treatment program on psychosocial functioning in schizophrenia.MethodsData were collected from the patients who applied to Dokuz Eylül University School of Medicine, Schizophrenia and Psychosis Outpatient Clinic. Seven schizophrenia patients who met schizophrenia according to DSM-V diagnostic criteria were included into the study. The level of psychosocial functioning was assessed using the Personal and Social Performance Scale (PSP), the positive and negative symptom severity was evaluated using the Positive and Negative Syndrome Scale (PANSS) and social skills were assessed by using the Social Skills Checklist (SSC). The VR psychosocial treatment program included 10 sessions and was carried on for five weeks as twice a week. Each session had different real virtual environment applications including social interaction components such as in a café to buy a beverage, a bazaar or market to do shopping, taking a bus, tram, and/or ferry, etc.ResultsPSP scores were statistically different after and before virtual reality assessment (p=0,018). SSC scores were trend to be significance after the VR application (p=0,062). After five weeks, patients’ the number of going outside home, the places they go and the activities they do have been increased compared to the numbers at the beginning but did not differ in statistically significance. None of the patients reported motion sickness due to exposure to real environment during or after immersive process of VR. There was no significant difference regarding PANSS scores after the VR psychosocial treatment. In this study real environment VR sessions did not trigger positive symptoms of schizophrenia patients.DiscussionIn this preliminary study, we found that the real environment VR psychosocial application is eligible for schizophrenia patients to improve their social skills and daily activities. This study helped patients to experience the real environment without being there and encouraged them to be “really” in there. Soon, cognitive remediation programs and psychosocial functioning therapies may be conducted via VR and may help the patients to cope with their symptoms and daily life difficulties.

The effects of the presence of others during a rowing exercise in a virtual reality environment

Overground gait training using virtual reality aimed at gait symmetry.

It is expected that See-Through Head-Mounted Display (STHMD), which superimposes the virtual environment generated by computer graphics (CG) on the real world, can vividly execute various simulations and designs by using both of the real and virtual environment around us. In STHMDs, information given as a virtual environment has to exactly match with the real environment, because both environments are visible. This is one of the problems to be solved for practical use. Particularly for matching of locations and size between real and virtual objects, disaccordance is likely to occur between the world coordinate of the real environment where the user of STHMD actually exists and that of the virtual environment described as parameters of CG, which directly causes displacement of locations where virtual objects are superimposed. This must be calibrated so that the virtual environment is superimposed properly. Among causes of such errors, we focused both on systematic errors of visual parameters caused in manufacturing process and differences between actual and supposed location of user's eye on STHMD when in use. The former is required to be calibrated only once after the fabrication of STHMDs, whereas the latter has to be calibrated every time users start using STHMDs. We have proposed calibration methods which are suitable to properties of these causes of errors. In the method, the direct fitting of the virtual cursor drawn in the virtual environment onto targets in the real environment is performed. Then, based on the result of fitting, the least square method identifies values of the visual parameters which minimize differences between locations of virtual cursor in the virutal environment and targets in the real environment. Application of the method to the STHMD which we have made is also repored. The differences between the virtal cursor and targets in the real environment due to systematic errors caused in the manufacturing process were reduced to about 1 [mm] per target, which was less than one-thirtieth of that before the calibration. The differences between the virtual cursor and targets in the real environment due to the location of user's eyes were also reduced about 2 [mm] per target, which was a half of that before the calibration. This result was well enough to prove the effectiveness of the calibration methods.

Nowadays the process of workstation design tends to include assessment steps in a virtual environment (VE) to evaluate the ergonomic features. These approaches are cost-effective and convenient since working directly on the digital mock-up in a VE is preferable to constructing a real physical mock-up in a real environment (RE). This study aimed at understanding the ability of a VR-based assembly tasks simulator to evaluate physical risk factors in ergonomics. Sixteen subjects performed simplified assembly tasks in RE and VE. Motion of the upper body and five muscle electromyographic activities were recorded to compute normalized and averaged objective indicators of discomfort, that is, rapid upper limb assessment score, averaged muscle activations, and total task time. Rated perceived exertion (RPE) and a questionnaire were used as subjective indicators of discomfort. The timing regime and complexity of the assembly tasks were investigated as within-subject factors. The results revealed significant differences between measured indicators in RE and VE. While objective measures indicated lower activity and exposure in VE, the subjects experienced more discomfort than in RE. Fairly good correlation levels were found between RE and VE for six of the objective indicators. This study clearly demonstrates that ergonomic studies of assembly tasks using VR are still challenging. Indeed, objective and subjective measurements of discomfort that are usually used in ergonomics to minimize the risks of work-related musculoskeletal disorders development exhibit opposite trends in RE and VE. Nevertheless, the high level of correlation found during this study indicates that the VR-based simulator can be used for such assessments.