| Editorial | | BIB | Full-Text | 1-2 | |
| Anna Spagnolli; Matthew Lombard; Luciano Gamberini | |||
| Personality variables and presence | | BIBAK | Full-Text | 3-13 | |
| Helene S. Wallach; Marilyn P. Safir; Roy Samana | |||
| The present study was designed to examine the correlation between five
personality traits (empathy, imagination, immersive tendencies, dissociation
tendencies and locus of control) and presence. Moreover, this study aimed to
identify an optimal virtual reality user's profile. Eighty-four students (66
women, 18 men) completed personality questionnaires, experienced exposure in a
virtual environment and completed a presence questionnaire. Twenty-three women,
among them 13 non-Jewish women and no men, neglected to look out the virtual
window, and reported lower levels of presence. Presence correlated with
immersive tendencies and empathy. However, empathy and internal locus of
control were the best predictors for the sense of presence. A correlation
between imagination and presence was only found in the group that avoided
viewing the virtual window. This study revealed the importance of empathy and
internal locus of control in the sense of presence. In addition, our findings
suggest that the subject's imagination has an important role when the virtual
environment is restricted and that we must attend to cultural and
gender-related factors when investigating therapy using virtual reality
technology. Keywords: Presence; Locus of control; Empathy; Immersion; Imagination; Dissociation;
Virtual reality; Ethnicity; Gender | |||
| Telepresence, soundscapes and technological expectation: putting the observer into the equation | | BIBAK | Full-Text | 15-25 | |
| Gary Pettey; Cheryl Campanella Bracken; Bridget Rubenking | |||
| In an experiment exploring the impact of sound on sensations of
telepresence, 126 participants watched a video clip using either headphones or
speakers. The results illustrate that sound is an important factor in
stimulating telepresence responses in audiences. Interactions between
soundscape and screen size were also revealed. A traverse interaction between
aural/visual congruency and soundscapes was evident. A second data set of 102
participants was collected to illuminate the effect of technological
expectation that emerged in the first study. Expectations had been mentioned in
other studies, and the data support the notion that people have an expectation
of the technological quality of a presentation. The results suggest that
examining expectations could assist in future conceptualizations of
telepresence. Keywords: Telepresence; Sound; Speakers; Headphones; Technological expectation | |||
| Distraction as a measure of presence: using visual and tactile adjustable distraction as a measure to determine immersive presence of content in mediated environments | | BIBAK | Full-Text | 27-42 | |
| Rolf Nordahl; Dannie Korsgaard | |||
| To assess and improve the user experience in entertainment products,
developers need results of evaluation methods, which in detail measure the
relationship between the mediated content and the resulting media experience.
This paper proposes a method applying adjustable distraction (AD) to determine
presence as immersion (Lombard and Ditton in At the heart of it all: the
concept of presence, Department of Broadcasting, Telecommunications and Mass
Media, Temple University, 1997) at selectable events (approximated real-time).
Two experiments were conducted to investigate its applicability in computer
games and movies with respectively visual and tactile AD. The first experiment
examined whether the experienced intensity in a survival-shooter game, measured
through questionnaires, was proportional to results from the AD method. The
intrusiveness of the AD method was also addressed in the experiment by
comparing the immersive presence ratings in a between-groups design. The second
experiment investigated whether heart rate measurements, intensity ratings and
the results of the AD method with vibration as the distraction signal were
proportional when test participants watched a movie clip. The outcome of the
first experiment indicated that no significant intrusion is caused by the
method. In addition, results showed no proportionality between the AD method
and intensity ratings. However, as the AD measurements were supported by flow
theory, it might be that the results from the AD method using visual
distraction are giving a more comprehensive indication of presence as immersion
(rather than just the intensity dimension). The second experiment revealed
proportionality between the intensity ratings and the heart rate measurements,
while the results from the tactile AD method were not proportional. We suspect
that this was caused by the great variance found across the test participants'
thresholds of perceivable vibration. Because of this, it is suggested that a
thorough screening process is conducted pre-test if the AD method should apply
vibration as the distracting stimulus. Keywords: Presence; Evaluation; Computer games; Visual; Tactile; Distraction;
Measurement | |||
| Measuring presence with verbal versus pictorial scales: a comparison between online- and ex post-ratings | | BIBAK | Full-Text | 43-53 | |
| Bartholomäus Wissmath; David Weibel; Fred W. Mast | |||
| In this study, we compare subjective online- and post-immersion measures.
Although its relevance appears obvious from a theoretical and applied research
perspective, this question has not yet been addressed in previous studies. In
addition, we also compare verbally and pictorially anchored scales. These
factors were measured in different contents using a 2x2x2 design. We
manipulated time of measure (online vs. ex post), type of measure (verbal vs.
visual), and content (language vs. language-free). Participants (N=162)
evaluated two video clips in terms of presence. No differences between averaged
online- and post-immersion measures were found and online judgments did not
interfere with the sensation of presence. In line with findings from other
areas of research, the use of pictorially anchored items has major advantages.
Our results suggest that those items require less mental workload and assess
the sensation of presence more directly than verbally anchored items. We
discuss the theoretical implications of our findings. Keywords: Presence; Online measurement; Post-rating; Verbal measures; Pictorial
measures; SAM | |||
| Brain activity and presence: a preliminary study in different immersive conditions using transcranial Doppler monitoring | | BIBAK | Full-Text | 55-65 | |
| Beatriz Rey; Mariano Alcañiz; José Tembl; Vera Parkhutik | |||
| Transcranial Doppler (TCD) sonography is a brain activity measurement
technique that monitors the hemodynamic characteristics of the major cerebral
arteries in normal and pathological conditions. As it is not invasive, it can
be easily used in combination with virtual environments (VE). In the present
study, TCD has been used to analyze brain activity variations in different
presence conditions during the exposure to a VE. Forty-two subjects have taken
part in the experience grouped in two different visualization conditions: a
CAVE-like and a single screen projection configuration. In each session, two
different navigation conditions were used: a free navigation (controlled by the
subject) and an automatic navigation (controlled by the system). Results show
that these immersion and navigation modifications in the VE generate changes in
brain activity that can be detected using TCD techniques. Several factors, one
of them being presence, could be having an influence on this behavior. Keywords: Presence; Brain activity; Transcranial Doppler; Virtual reality; Immersion;
Navigation | |||
| Perceiving interpersonally-mediated risk in virtual environments | | BIBAK | Full-Text | 67-76 | |
| David B. Portnoy; Natalie D. Smoak; Kerry L. Marsh | |||
| Using virtual reality (VR) to examine risky behavior that is mediated by
interpersonal contact, such as agreeing to have sex, drink, or smoke with
someone, offers particular promise and challenges. Social contextual stimuli
that might trigger impulsive responses can be carefully controlled in virtual
environments (VE), and yet manipulations of risk might be implausible to
participants if they do not feel sufficiently immersed in the environment. The
current study examined whether individuals can display adequate evidence of
presence in a VE that involved potential interpersonally-induced risk: meeting
a potential dating partner. Results offered some evidence for the potential of
VR for the study of such interpersonal risk situations. Participants' reaction
to the scenario and risk-associated responses to the situation suggested that
the embodied nature of virtual reality override the reality of the risk's
impossibility, allowing participants to experience adequate situational
embedding, or presence. Keywords: Presence; Sexual risk; Embodiment; Interpersonal risk | |||
| Relating conversational expressiveness to social presence and acceptance of an assistive social robot | | BIBAK | Full-Text | 77-84 | |
| Marcel Heerink; Ben Kröse; Vanessa Evers; Bob Wielinga | |||
| Exploring the relationship between social presence, conversational
expressiveness, and robot acceptance, we set up an experiment with a robot in
an eldercare institution, comparing a more and less social condition.
Participants showed more expressiveness with a more social agent and a higher
score on expressiveness correlated with higher scores on social presence.
Furthermore, scores on social presence correlated with the scores on the
intention to use the system in the near future. However, we found no
correlation between conversational expressiveness and robot acceptance. Keywords: Social presence; Technology acceptance; Social robots; Gerontechnology;
Human-robot interaction | |||
| Toward the development of interactive virtual dissection with haptic feedback | | BIBAK | Full-Text | 85-103 | |
| Nasim Melony Vafai; Shahram Payandeh | |||
| Traditional, hands-on dissection of an animal is common practice in many
classrooms to aid in the study of anatomy and biology. More specifically,
virtual dissection environments have been developed making it possible to study
the inner workings of animals without cutting them up. In this paper, we
present a novel virtual reality dissection simulator, where a user can dissect
an animal (i.e. frog) and its organs using a 3D force feedback haptic device.
The simulator uses force feedback as part of a multimodal cue to provide
guidance and performance feedback to the user. This paper highlights
methodologies which are used for addressing some of the key challenges involved
in designing and developing simulators, such as: modelling and mechanics of
deformation, collision detection between multiple deformable bodies, and haptic
feedback. Keywords: Virtual reality; Object deformation; Cutting; Dissection; Collision
detection; Haptics; Force feedback | |||
| Exploring individual user differences in the 2D/3D interaction with medical image data | | BIBAK | Full-Text | 105-118 | |
| Elena Zudilova-Seinstra; Boris van Schooten; Avan Suinesiaputra | |||
| User-centered design is often performed without regard to individual user
differences. In this paper, we report results of an empirical study aimed to
evaluate whether computer experience and demographic user characteristics would
have an effect on the way people interact with the visualized medical data in a
3D virtual environment using 2D and 3D input devices. We analyzed the
interaction through performance data, questionnaires and observations. The
results suggest that differences in gender, age and game experience have an
effect on people's behavior and task performance, as well as on subjective user
preferences. Keywords: 2D/3D interaction; Medical segmentation; Virtual environments; Multimodal;
User study | |||
| Visualization and simulation of 3D artificial neural structures generated by L-system | | BIBAK | Full-Text | 119-129 | |
| Regina Célia Coelho; Nivaldi, Jr. Calonego; Luís Augusto Consularo | |||
| This paper presents the visualization and simulation environment of 3D
artificial neural structures. A stochastic L-system has been employed to
generate neural structures based on features extracted from natural cells and
it takes into account an hierarchical description of each neurite to allow
interactions of the users in the virtual environment built. The implemented
distributed virtual reality environment has its architecture explained, as well
as its user interaction features to handle virtual neural structures.
Furthermore, attraction/repulsion trophic fields had their effects simulated
into these virtual neural structures. This approach illustrates aspects related
to the neurogenesis and neural reorganization processes regarding attractive,
repulsive or both interaction fields. Keywords: L-system; Stochastic L-system; Neural growth; Neural simulation; Virtual
reality environment; Collaborative environments | |||
| Nu!RehaVR: virtual reality in neuro tele-rehabilitation of patients with traumatic brain injury and stroke | | BIBAK | Full-Text | 131-141 | |
| Osvaldo Gervasi; Riccardo Magni; Mauro Zampolini | |||
| The availability of virtual environments on the Web is fostering new
applications of virtual reality in several fields, including some therapeutical
applications. We present an application of virtual reality applied to the
tele-rehabilitation of patients with traumatic brain injury and stroke. Our
system, based on X3D and Ajax3D technologies, enhances the possibility of
making tele-rehabilitation exercises aimed at the recovery of the neurological
disease. The system, called Nu!RehaVR, has been designed to integrate the
activity carried out on a tele-rehabilitation system, Nu!Reha (Nu!Reha is a
trademark of Pragma Engineering srl. See http://www.nureha.eu) desk, with the
activities performed in the virtual worlds, through some rehabilitation
exercises in contexts incompatible with the patients' impairments (not able to
move or forced in static positions because of therapies, etc.). The
architecture of Nu!RehaVR and the environments associated to two exercises,
"Utilising an elevator to reach a given floor" and "Crossing a road using a
traffic light", are illustrated. These exercises can be considered as
prototypes of a series of tele-rehabilitation exercises which help to stimulate
the patients performing actions in relatively dangerous scenarios. The system
is designed to allow the remote monitoring and assessment of the patient's
activities by the medical staff at the hospital using the communication
facilities of the tele-rehabilitation system. Keywords: Nu!RehaVR; Virtual reality; Tele-rehabilitation; Neurological disease;
Nu!Reha desk; Traumatic brain Injury; Stroke patients; X3D; Ajax3D | |||
| Auditory and visual 3D virtual reality therapy for chronic subjective tinnitus: theoretical framework | | BIBAK | Full-Text | 143-151 | |
| Alain Londero; Isabelle Viaud-Delmon; Alexis Baskind; Olivier Delerue | |||
| It is estimated that 10% of the adult population in developed countries is
affected by subjective tinnitus. Physiopathology of subjective tinnitus remains
incompletely explained. Nevertheless, subjective tinnitus is thought to result
from hyperactivity and neuroplastic reorganization of cortical and subcortical
networks following acoustic deafferentation induced by cochlear or auditory
nerve damage. Involvement of both auditory and non-auditory central nervous
pathways explains the conscious perception of tinnitus and also the potentially
incapacitating discomfort experienced by some patients (sound hypersensitivity,
sleep disorders, attention deficit, anxiety or depression). These clinical
patterns are similar to those observed in chronic pain following amputation
where conditioning techniques using virtual reality have been shown both to be
theoretically interesting and effectively useful. This analogy led us to
develop an innovative setup with dedicated auditory and visual 3D virtual
reality environments in which unilateral subjective tinnitus sufferers are
given the possibility to voluntarily manipulate an auditory and visual image of
their tinnitus (tinnitus avatar). By doing so, the patients will be able to
transfer their subjective auditory perception to the tinnitus avatar and to
gain agency on this multimodal virtual percept they hear, see and spatially
control. Repeated sessions of such virtual reality immersions are then supposed
to contribute to tinnitus treatment by promoting cerebral plasticity. This
paper describes the theoretical framework and setup adjustments required by
this very first attempt to adapt virtual reality techniques to subjective
tinnitus treatment. Therapeutic usefulness will be validated by a further
controlled clinical trial. Keywords: Tinnitus; Virtual reality; Neuroplasticity | |||
| Guest editors' foreword to the second issue on virtual reality in scientific application | | BIB | Full-Text | 153 | |
| Osvaldo Gervasi; Roberto Ranon | |||
| Illuminating the past: state of the art | | BIBAK | Full-Text | 155-182 | |
| Jassim Happa; Mark Mudge; Kurt Debattista; Alessandro Artusi | |||
| Virtual reconstruction and representation of historical environments and
objects have been of research interest for nearly two decades. Physically based
and historically accurate illumination allows archaeologists and historians to
authentically visualise a past environment to deduce new knowledge. This report
reviews the current state of illuminating cultural heritage sites and objects
using computer graphics for scientific, preservation and research purposes. We
present the most noteworthy and up-to-date examples of reconstructions
employing appropriate illumination models in object and image space, and in the
visual perception domain. Finally, we also discuss the difficulties in
rendering, documentation, validation and identify probable research challenges
for the future. The report is aimed for researchers new to cultural heritage
reconstruction who wish to learn about methods to illuminate the past. Keywords: Cultural heritage; Computer graphics; Image-processing; Rendering; Global
illumination; Reflectance transformation imaging; High dynamic range imaging;
Sky modelling; Flame modelling; Colour science; Visual perception | |||
| GPU-based real-time acoustical occlusion modeling | | BIBAK | Full-Text | 183-196 | |
| Brent Cowan; Bill Kapralos | |||
| In typical environments, the direct path between a sound source and a
listener is often occluded. However, due to the phenomenon of diffraction,
sound still reaches the listener by "bending" around an obstacle that lies
directly in the line of straight propagation. Modeling occlusion/diffraction
effects is a difficult and computationally intensive task and thus generally
ignored in virtual reality and videogame applications. Driven by the gaming
industry, consumer computer graphics hardware and the graphics processing unit
(GPU) in particular, have greatly advanced in recent years, outperforming the
computational capacity of central processing units. Given the affordability,
widespread use, and availability of computer graphics hardware, here we
describe a computationally efficient GPU-based method that approximates
acoustical occlusion/diffraction effects in real time. Although the method has
been developed primarily for videogames where occlusion/diffraction is
typically overlooked, it is relevant for dynamic and interactive virtual
environments as well. Keywords: Graphics processing unit; Acoustical occlusion; Acoustical diffraction;
Spatial sound; Real-time | |||
| CAVE for collaborative patient room design: analysis with end-user opinion contrasting method | | BIBAK | Full-Text | 197-211 | |
| Mikael Wahlström; Miika Aittala; Helinä Kotilainen; Tiina Yli-Karhu | |||
| Several studies indicate that virtual reality (VR) systems are useful for
end-user participation in an environmental design process. However, these
systems can be costly and thus support for the decision whether to invest in a
VR of some type is useful. This study presents a novel method for analysing the
usefulness of a VR system for the purpose of end-user participation. We
collected qualitative end-user opinion data in the real environment and then
contrasted this data with the capabilities of a VR system. Additionally, to
better understand the capabilities of the VR used, we examined how the
end-users perceive the used virtual environment, which in this case was CAVE,
an immersive VR system where projectors are directed to the walls of a
room-sized cube. In this way, we analysed whether the same functions and
elements identified by end-users on the actual wards could also be evaluated in
the CAVE. Eleven nurses and 11 patients participated in the study by evaluating
a bathroom and/or four patient rooms modelled by the CAVE and the actual
hospital wards. The CAVE was convenient for evaluating most issues identified
by the study participants in the actual hospital wards, i.e. aesthetics;
correct location of equipment, supplies and materials; distraction by or the
good companion of other patients as well as window position and size and
living/workspace. However, it was not possible to evaluate with full certainty
the possibilities for bracing against grab bars or other objects in the VR, and
this was found to be relevant to the independent functioning of patients with
limited mobility. Also, due to the relatively low luminance levels of
projectors, evaluations regarding lighting were considered unreliable.
Moreover, end-users were not always certain about the sizes and sufficiency of
space in the CAVE. Solutions to overcome these limitations were proposed. Keywords: Virtual reality; CAVE; Patient room design; End-user participation;
Collaborative design | |||
| Pace-sync shoes: intuitive walking-pace guidance based on cyclic vibro-tactile stimulation for the foot | | BIBAK | Full-Text | 213-219 | |
| Junji Watanabe; Hideyuki Ando | |||
| We propose a walking guidance method with a sandal-shaped vibration
interface and describe two experiments we performed to formulate the design
principles of the interface. In the interface, a vibrating motor presents
timing information to the foot, and pressure sensors measure walking pace. Our
method is a combination of the walking-state monitoring and vibro-tactile
feedback to maintain or promote a walking pace. Vibration stimuli with a
constant presentation interval are alternately and repeatedly given to the
right or left foot of the user according to the measured walking pace, and then
the walking pace gradually conforms to the presented interval of the vibration.
In the experiments, we specified the effective timing and intervals of the
vibration stimuli for efficient inductance of walking pace. The method is
applicable for training and coaching in sports and rehabilitation in health
care. Keywords: Walking guidance; Walking pace; Foot stimulation; Vibro-tactile stimulation;
Sensory-motor synchronization | |||
| Piavca: a framework for heterogeneous interactions with virtual characters | | BIBA | Full-Text | 221-228 | |
| Marco Gillies; Xueni Pan; Mel Slater | |||
| This paper presents a virtual character animation system for real-time multimodal interaction in an immersive virtual reality setting. Human to human interaction is highly multimodal, involving features such as verbal language, tone of voice, facial expression, gestures and gaze. This multimodality means that, in order to simulate social interaction, our characters must be able to handle many different types of interaction and many different types of animation, simultaneously. Our system is based on a model of animation that represents different types of animations as instantiations of an abstract function representation. This makes it easy to combine different types of animation. It also encourages the creation of behavior out of basic building blocks, making it easy to create and configure new behaviors for novel situations. The model has been implemented in Piavca, an open source character animation system. | |||
| Human interactions and personal space in collaborative virtual environments | | BIBAK | Full-Text | 229-240 | |
| Nasser Nassiri; Norman Powell; David Moore | |||
| As humans start to spend more time in collaborative virtual environments
(CVEs) it becomes important to study their interactions in such environments.
One aspect of such interactions is personal space. To begin to address this, we
have conducted empirical investigations in a non immersive virtual environment:
an experiment to investigate the influence on personal space of avatar gender,
and an observational study to further explore the existence of personal space.
Experimental results give some evidence to suggest that avatar gender has an
influence on personal space although the participants did not register high
personal space invasion anxiety, contrary to what one might expect from
personal space invasion in the physical world. The observational study suggests
that personal space does exist in CVEs, as the users tend to maintain, in a
similar way to the physical world, a distance when they are interacting with
each other. Our studies provide an improved understanding of personal space in
CVEs and the results can be used to further enhance the usability of these
environments. Keywords: Collaborative virtual environment; Anxiety; Personal space | |||
| Interactive multi-modal suturing | | BIBAK | Full-Text | 241-253 | |
| Shahram Payandeh; Fuhan Shi | |||
| We present a mechanics-based interactive multi-modal environment designed as
part of a serious gaming platform. The specific objectives are to teach basic
suturing and knotting techniques for simple skin or soft tissue wound closure.
The pre-wound suturing target, skin, or deformable tissue is modeled as a
modified mass-spring system. The suturing material is designed as a
mechanics-based deformable linear object. Tools involved in a typical suturing
procedures are also simulated. Collision management modules between the soft
tissue and the needle, the soft tissue and the suture are analyzed. In addition
to modeling the interactive environment of a typical suturing procedure, basics
of the modeling approaches on the evaluation of a stitch formed by the user are
also discussed. For example, if needle insertion points are too close from each
other or to the edge of the wound, when the suture is pulled, the suture will
tear the soft tissue instead of suturing the incision together. Experiment
results show that our simulator can run on a standard personal computer and
allow users to perform different suturing patterns with smooth graphics and
haptic feedback. Keywords: Virtual suturing; Suture model; Wound closure; Tissue tearing; Haptic
feedback; Surgical training environment; Serious games | |||
| Developing serious games for cultural heritage: a state-of-the-art review | | BIBAK | Full-Text | 255-275 | |
| Eike Falk Anderson; Leigh McLoughlin; Fotis Liarokapis | |||
| Although the widespread use of gaming for leisure purposes has been well
documented, the use of games to support cultural heritage purposes, such as
historical teaching and learning, or for enhancing museum visits, has been less
well considered. The state-of-the-art in serious game technology is identical
to that of the state-of-the-art in entertainment games technology. As a result,
the field of serious heritage games concerns itself with recent advances in
computer games, real-time computer graphics, virtual and augmented reality and
artificial intelligence. On the other hand, the main strengths of serious
gaming applications may be generalised as being in the areas of communication,
visual expression of information, collaboration mechanisms, interactivity and
entertainment. In this report, we will focus on the state-of-the-art with
respect to the theories, methods and technologies used in serious heritage
games. We provide an overview of existing literature of relevance to the
domain, discuss the strengths and weaknesses of the described methods and point
out unsolved problems and challenges. In addition, several case studies
illustrating the application of methods and technologies used in cultural
heritage are presented. Keywords: Cultural heritage; Serious games; Computer games technology | |||
| Context-driven interaction in immersive virtual environments | | BIBAK | Full-Text | 277-290 | |
| Scott Frees | |||
| There are many interaction tasks a user may wish to accomplish in an
immersive virtual environment. A careful examination of these tasks reveals
that they are often performed under different contexts. For each task and
context, specialized interaction techniques can be developed. We present the
context-driven interaction model: a design pattern that represents contextual
information as a first-class, quantifiable component within a user interface
and supports the development of context-sensitive applications by decoupling
context recognition, context representation, and interaction technique
development. As a primary contribution, this model provides an enumeration of
important representations of contextual information gathered from across the
literature and describes how these representations can effect the selection of
an appropriate interaction technique. We also identify how several popular 3D
interaction techniques adhere to this design pattern and describe how the
pattern itself can lead to a more focused development of effective interfaces.
We have constructed a formalized programming toolkit and runtime system that
serves as a reference implementation of the context-driven model and a
discussion is provided explaining how the toolkit can be used to implement a
collection of representative 3D interaction interfaces. Keywords: Human-computer interaction; Context-sensitive interaction; Virtual reality;
Virtual environments, 3DUI, interaction techniques | |||