Reaching within video-capture virtual reality: using virtual reality as a motor control paradigm.

We have developed a virtual reality (VR) system that integrates a three-dimensional tracking device with a video-capture VR platform to record upper limb movements. The influence of target velocity on planning and execution of reaching movements was studied in five healthy subjects. Our initial results suggest that a target's velocity is considered when planning an interceptive action and that a hand reaching toward a moving virtual target is controlled in a similar way to how it is in the real visual environment.     

Velocity constancy in a virtual reality environment

During everyday life the brain is continuously integrating multiple perceptual cues in order to allow us to make decisions and to guide our actions. In this study we have used a simulated (virtual reality--VR) visual environment to investigate how cues to speed judgments are integrated. There are two sources that could be used to provide signals for velocity constancy: temporal-frequency or distance cues. However, evidence from most psychophysical studies favours temporal-frequency cues. Here we report that two depth cues that provide a relative object--object distance--disparity and motion parallax--can provide a significant input to velocity-constancy judgments, particularly when combined. This result indicates that the second mechanism can also play a significant role in generating velocity constancy. Furthermore, we show that cognitive factors, such as familiar size, can influence the perception of object speed. The results suggest that both low-level cues to spatiotemporal structure and depth, and high-level cues, such as object familiarity, are integrated by the brain during velocity estimation in real-world viewing.     

Immersiveness and physiological arousal within panoramic video-based virtual reality.

In this paper, we discuss findings from a study that used panoramic video-based virtual environments (PVVEs) to induce self-reported anger. The study assessed "immersiveness" and physiological correlates of anger arousal (i.e., heart rate, blood pressure, galvanic skin response [GSR], respiration, and skin temperature). Results indicate that over time, panoramic video-based virtual scenarios can be, at the very least, physiologically arousing. Further, it can be affirmed from the results that hypnotizability, as defined by the applied measures, interacts with group on physiological arousal measures. Hence, physiological arousal appeared to be moderated by participant hypnotizability and absorption levels.     

Virtual reality as a representative training environment for football referees

Visual experience plays an important role in facilitating referee decision-making. Video training can be used to train these perceptual-cognitive skills in discrete scenarios, for instance in foul situations in football, but is less suitable in other instances such as when seeking to make decisions in open-play scenarios due to a lack of representativeness. Recent technological advances enable the use of virtual reality (VR) to replicate game situations in a controlled and realistic manner. It is however not yet known how representative behaviour in VR would be of behaviour on-field in the natural environment. The aim of the study was therefore to examine the degree to which visual behaviour of football referees in virtual reality would reflect behaviour found when adjudicating matches on-field. Sub-elite football referees completed decision-making tasks in three experimental conditions: on-field (in a real match), in virtual reality and when observing video footage. Across the three environments we compared decision-making performance, visual behaviour (including search rate, fixation duration, and head movements) and the user experience of the referees. Results revealed that behaviour in the VR environment was indistinguishable from that on-field. In contrast, visual-motor behaviour when observing video footage was markedly different to that found on-field (and in VR). The results show that visual-motor behaviour in VR is representative of that found on-field and therefore suggests that VR offers promise as a representative training environment for sports officials to improve on-field performance in the natural environment.     

Nurturing behavioral repertoires within a nonsupportive environment

Recent articles have expressed concern over the increasing retreat to mentalism among behaviorists. The problem has been described elsewhere as a shift in verbal behavior resulting from the contingencies imposed by mentalistic verbal communities. Previous solutions have focused on strengthening our behavioral graduate programs to make the graduates' verbal repertoires more resistant to change. We suggest it is useful to analyze the problem in terms of inappropriate audience control and offer an approach by which behaviorists may assemble audiences to maintain their behavioral verbal repertoires within mentalistic verbal communities.     

Contextual fear conditioning predicts subsequent avoidance behaviour in a virtual reality environment

Avoidance behaviour is a crucial component of fear and is importantly involved in the maintenance of anxiety disorders. Presumably, fear conditioning leads to avoidance of the feared object or context. A virtual reality contextual fear conditioning paradigm was used to investigate the association between explicit conditioning effects and subsequent avoidance behaviour. Mild electric shocks were administered in one context (anxiety context), but never in a second context (safety context). Subsequent avoidance behaviour was assessed by asking participants to choose two out of three contexts (a neutral context was added) to visit again. Participants avoided the anxiety context, but did not prefer the safety over the neutral context. Participants with substantial conditioning effects, as reflected in differential valence, arousal and anxiety ratings, avoided the anxiety context but not the safety context. In sum, we demonstrated an association between context conditioning effects on an explicit level and later avoidance behaviour.     

Contextual fear conditioning predicts subsequent avoidance behaviour in a virtual reality environment

Avoidance behaviour is a crucial component of fear and is importantly involved in the maintenance of anxiety disorders. Presumably, fear conditioning leads to avoidance of the feared object or context. A virtual reality contextual fear conditioning paradigm was used to investigate the association between explicit conditioning effects and subsequent avoidance behaviour. Mild electric shocks were administered in one context (anxiety context), but never in a second context (safety context). Subsequent avoidance behaviour was assessed by asking participants to choose two out of three contexts (a neutral context was added) to visit again. Participants avoided the anxiety context, but did not prefer the safety over the neutral context. Participants with substantial conditioning effects, as reflected in differential valence, arousal and anxiety ratings, avoided the anxiety context but not the safety context. In sum, we demonstrated an association between context conditioning effects on an explicit level and later avoidance behaviour.     

Using a virtual reality system to study balance and walking in a virtual outdoor environment: a pilot study.

Falls and fall-related injuries are a major problem for elderly persons. Most falls occur during walking and turning, and the risk of falling increases when attention is diverted to something besides walking. It is often difficult to standardize methods for testing balance and fall tendency in a clinically relevant setting. We describe the development of a system using a virtual environment (VE) to assess how attention demanding and unexpected events influence a person's capacity to control balance and movement. The hardware in the system consists of a head-mounted display (HMD), a magnetic tracker system, and two SGI computers. The software consists of the image generation of the VE and the management and visualization of motion tracking data. In a preliminary pilot study eight subjects (age 23-80) participated. Each subject walked on a normal floor and was visually presented a familiar outdoor environment in the HMD. They were exposed to different unexpected events, such as a virtual snowfall and tilting of the VE. Disturbances of balance and walking patterns such as changes in speed, stride length and balance reactions like slipping were observed. Two subjects experienced symptoms of cyber sickness with a SSQ score above 25 points. Walking with sensors only did not affect walking time, but in VE the subjects generally walked more slowly. Virtual tilting of the environment had an impact on balance performance during walking. This effect was not observed while the test subjects were walking in a virtual snowfall. The model needs further development but may hold a potential for clinical use.     

Gaze direction affects walking speed when using a self-paced treadmill with a virtual reality environment

BackgroundIn a previous study it was observed that participants increase their walking speed during a dual task while walking on a self-paced treadmill in a virtual reality (VR) environment (Gait Real time Analysis Interactive Lab (GRAIL)). This observation is in contrast with the limited resources hypothesis, which suggests walking speed of healthy persons to decrease when performing a cognitive dual task.AimThe aim of the present study was therefore to determine whether the cognitive demand of the task, an aroused feeling, discrepancy in optic flow or a change in gaze direction caused participants to walk faster in this computer assisted rehabilitation environment.MaterialsThe GRAIL included a self-paced treadmill, a motion-capture system and synchronized VR environments.MethodsThirteen healthy young adults (mean age 21.6 ± 2.5) were included in this study. Participants walked on the self-paced treadmill while seven different intervention conditions (IC) were offered. Prior to each IC, a control condition (CC) was used to determine the natural self-selected walking speed. Walking speed during the last 30 s of each IC was compared with the walking speed during the last 30 s of the preceding CC.ResultsResults show that the height on which a visual task was presented in the VR environment, influenced walking speed. Participants walked faster when gaze was directed above the focus of expansion.SignificanceThese findings contribute to a further understanding of the differences between walking in a real life environment or computer assisted rehabilitation environment. When analyzing gait on a self-paced treadmill in the future, one must be attentive where to place a visual stimulus in the VR environment.     

Understanding consumers' purchase intention in virtual reality commerce environment

Virtual reality (VR) has developed rapidly and drawn the attention of businesses. E-commerce practitioners have used VR to improve business performance and satisfy consumers' needs by enhancing the shopping experience and increasing purchase intention. To explore the effects of VR shopping platforms on purchase intention, this study developed a theoretical framework on the basis of task–technology fit. The framework comprises technological characteristics and user needs (intrinsic and extrinsic motivation) and can be used to investigate perceived needs–technology fit and identify factors affecting intention to purchase on VR platforms. This study distributed an online questionnaire and received 336 responses. Analysis was performed using partial least squares structural equation modeling. The results suggested that purchase intention is stronger when perceived needs–technology fit is closer. Hedonic needs play a vital role in perceived needs–technology fit. In terms of technological characteristics, relative advantage, and service compatibility strongly affect perceived needs–technology fit. In addition, feelings of spatial presence, a key component of VR, positively affect relative advantage, service compatibility, and trialability and negatively affect complexity. The implications of the findings are also discussed.     

Stronger reactivity to social gaze in virtual reality compared to a classical laboratory environment

People show a robust tendency to gaze at other human beings when viewing images or videos, but were also found to relatively avoid gaze at others in several real-world situations. This discrepancy, along with theoretical considerations, spawned doubts about the appropriateness of classical laboratory-based experimental paradigms in social attention research. Several researchers instead suggested the use of immersive virtual scenarios in eliciting and measuring naturalistic attentional patterns, but the field, struggling with methodological challenges, still needs to establish the advantages of this approach. Here, we show using eye-tracking in a complex social scenario displayed in virtual reality that participants show enhanced attention towards the face of an avatar at near distance and demonstrate an increased reactivity towards her social gaze as compared to participants who viewed the same scene on a computer monitor. The present study suggests that reactive virtual agents observed in immersive virtual reality can elicit natural modes of information processing and can help to conduct ecologically more valid experiments while maintaining high experimental control.     

The effect of a virtual reality environment on gaze behaviour and motor skill learning

ObjectiveVirtual reality (VR) systems hold significant potential for training skilled behaviours and are currently receiving intense interest in the sporting domain. They offer both practical and pedagogical benefits, but there are concerns about the effect that perceptual deficiencies in VR systems (e.g. reduced haptic information, and stereoscopic display distortions) may have on learning and performance. ‘Specificity of learning’ theories suggest that VR could be ineffective (or even detrimental) if important differences (e.g. perceptual deficiencies) exist between practice and real task performance conditions. Nevertheless, ‘structural learning’ theories suggest VR could be a useful training tool, despite these deficiencies, because a trainee can still learn the underlying structure of the behaviour. We explored these theoretical predictions using golf putting as an exemplar skill.MethodIn Experiment 1 we used a repeated measures design to assess putting accuracy (radial error) and quiet eye duration of expert golfers (n = 18) on real putts before and after 40 VR ‘warm up’ putts. In Experiment 2, novice golfers (n = 40) were assigned to either VR or real-world putting training. Putting accuracy and quiet eye durations were then assessed on a real-world retention test.ResultsBoth visual guidance (quiet eye) and putting accuracy were disrupted temporarily when moving from VR to real putting (Experiment 1). However, real-world and VR practice produced comparable improvements in putting accuracy in novice golfers (Experiment 2).ConclusionOverall, the results suggest that: (i) underlying skill structures can be learned in VR and transferred to the real-world; (ii) perceptual deficiencies will place limits on the use of VR. These findings demonstrate the challenges and opportunities for VR as a training tool, and emphasise the need to empirically test the costs and benefits of specific systems before deploying VR training.     

Initial validation of a virtual environment for assessment of memory functioning: virtual reality cognitive performance assessment test.

The current project is an initial attempt at validating the Virtual Reality Cognitive Performance Assessment Test (VRCPAT), a virtual environment-based measure of learning and memory. To examine convergent and discriminant validity, a multitrait-multimethod matrix was used in which we hypothesized that the VRCPAT's total learning and memory scores would correlate with other neuropsychological measures involving learning and memory but not with measures involving potential confounds (i.e., executive functions; attention; processing speed; and verbal fluency). Using a sequential hierarchical strategy, each stage of test development did not proceed until specified criteria were met. The 15-minute VRCPAT battery and a 1.5-hour in-person neuropsychological assessment were conducted with a sample of 30 healthy adults, between the ages of 21 and 36, that included equivalent distributions of men and women from ethnically diverse populations. Results supported both convergent and discriminant validity. That is, findings suggest that the VRCPAT measures a capacity that is (a) consistent with that assessed by traditional paper-and-pencil measures involving learning and memory and (b) inconsistent with that assessed by traditional paper-and-pencil measures assessing neurocognitive domains traditionally assumed to be other than learning and memory. We conclude that the VRCPAT is a valid test that provides a unique opportunity to reliably and efficiently study memory function within an ecologically valid environment.     

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

ObjectivesThe aim of the study was to test the performance, motivational, and affective impact of aerobic exercise within an immersive virtual reality environment experienced alone or with another individual.DesignSixty female participants aged 18–30 years were assigned to one of three conditions: no virtual reality (NVR), individual virtual reality (IVR), or companion virtual reality (CVR).MethodParticipants completed 9 min of self-paced rowing on an ergometer without any visual input or performance feedback (NVR), individually within a virtual reality environment (IVR), or within a virtual reality environment that included a companion depicted as an avatar (CVR).ResultsThe two virtual reality groups rowed a further distance and at a higher power output than the NVR group. Furthermore, the CVR group outperformed the IVR group in distance and had a higher heart rate. Participants in the virtual reality groups did not perceive themselves to be exerting more physical effort and rated the task as more enjoyable than participants in the NVR group.ConclusionsVirtual reality improves performance and the affective response to aerobic exercise, and performance effects are further enhanced by the presence of others in the virtual environment.     

Stimulus-response compatibility with pure and mixed mappings in a flight task environment

The present study examined the stimulus-response compatibility (SRC) effect in a simulated flight environment. Experiments 1 and 2 tested the effect with pure and mixed mappings in flight tasks by using attitude displays with inside-out and outside-in formats, whereas Experiments 3 and 4 used a simplified display and tasks. The SRC effect was obtained with mixed mappings when responses were turns of a flight yoke (Experiments 1-3). In contrast, the SRC effect was absent with mixed mappings when they were buttonpresses (Experiment 4). Analyses of sequential effects suggest that the reduction in Experiments 1-3 can be attributed to reduction in the frequency of trials for which the congruent mapping repeats, but the elimination in Experiment 4 cannot be. Implications of the findings are discussed in the context of aviation cockpit design.     

Virtual reality applications to agoraphobia: a protocol.

Recently, educators and instructional designers have focused on the development and implementation of virtual learning environments that effectively combine theoretical and applied knowledge to teach university students. One of the trusts of the Psychology Virtual Teaching Laboratory in collaboration with the IXTLI observatory is to develop dissemination programs to promote the insertion of virtual reality (VR) technologies applied to rehabilitation in their clinical practice. This paper describes the development of (1) agoraphobia VR learning objects to be use as a teaching support tools in class and (2) a multimedia teaching program that incorporate digital video and VR scenarios address to students in the field of mental health. Promotion among professors and students about the use of this technology will allow us to initiate research in our country as well as to validate contextualized applications for our culture, therefore contributing with new advances in this field.     

Presence and emotions in playing a group game in a virtual environment: the influence of body participation

This study assesses the influence of body participation on the sense of presence and emotions, and the relationship between the two dependent variables in playing a group game in a virtual environment. A total of 56 volunteers were asked to play a virtual game in a 360-degree stereoscopic immersive interactive visualization environment using either body movement or a joystick. Presence was measured with the post hoc SUS Presence Questionnaire. The pictorial tool of Self-Assessment Manikin was employed for measuring emotions of arousal and valence. Both arousal and valence positively correlated with presence. However, body participation did not significantly affect reported presence or the above-mentioned emotions.