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At least 451 records · Page 25Linked to original sources

PubMed2004

Developing multimedia software and virtual reality worlds and their use in rehabilitation and psychology.

The multimedia and virtual reality projects performed at our laboratory during the last ten years can be grouped into the following groups: 1) tutorial and entertainment programs for handicapped children, 2) rehabilitation programs for stroke patients and patients with phobias. We have developed multimedia software for handicapped children with various impairments: partial vision, hearing difficulties, locomotive difficulties, mental retardation, dyslexia etc. In the present paper we show the advantages of using multimedia software to develop mental skills in handicapped people and deal with the special needs of handicapped children. For the rehabilitation of stroke patients we have developed a computer-controlled method, which enables - contrary to methods used internationally - not only the establishment of a diagnosis, but also measurement of therapy effectiveness: 1) it enables us to produce a database of patients, which contains not only their personal data but also test results, their drawings and audio recordings, 2) it is in itself an intensive therapeutic test and contains tutorial programs. We are currently collecting test results. We have also developed some virtual worlds for treating phobias: a virtual balcony and a ten-story building with an external glass elevator as well as an internal glass elevator in the virtual Atrium Hyatt hotel. We have developed a virtual environment for treating claustrophobia too: a closed lift and a room where the walls can move. For specific phobias (fear of travelling) we have modelled the underground railway system in Budapest. For autistic children, we have developed virtual shopping software too. In this paper we present the advantages of virtual reality in the investigation, evaluation and treatment of perception, behaviour and neuropsychological disorders.

Child↗

PubMed2002

Behavioral avoidance dynamics in the presence of a virtual spider.

Tracking behavior with a virtual spider and a neutral target is compared in fearful and nonfearful subjects. Head-tracking in virtual environments appears to be a scale-free behavior with long-range fractal-like patterns. Moreover, these fractal patterns change according to what the target affords the tracker and the level of behavioral avoidance manifested by the subjects. Results are interpreted in terms of ecological psychology and nonlinear dynamics, and implications for virtual reality (VR) psychology are outlined.

Adult↗

PubMed2004

Comparison of the implantability of electronic hearing devices in a virtual reality planning environment and in human temporal bones.

OBJECTIVE: To develop a procedure using a virtual reality (VR) environment that permitted us to simulate the preoperative fitting of an electronic implantable hearing device (IHD) and assess its implantability. MATERIAL AND METHODS: This was an experimental, prospective study based on VR simulations involving the pre- and postoperative comparison of the implantability of an IHD. The preoperative possibility of implanting an IHD in a VR environment was compared with the postoperative implantability of the device in the temporal bones of human cadavers and patients. Study groups were analyzed according to the criteria "VR implantation" and "real surgery" using contingency tables. RESULTS: A computer simulation method based on CT images was developed for the preoperative planning of the implantation. The VR simulation proved feasible in all cases (15 temporal bones and 24 patients). There was no significant difference between the process of implanting the IHD in patients or in the VR environment. These results indicate that VR-based test fittings of an IHD allow prediction of the implantability of an IHD prior to actual surgery. CONCLUSION: We have described the development of a novel VR procedure for predicting the implantability of hearing devices in otoneurosurgical applications. The VR procedure can be applied universally and may also be used for other parts of the body.

Adult↗

PubMed1999

VRUSE--a computerised diagnostic tool: for usability evaluation of virtual/synthetic environment systems.

A special questionnaire (VRUSE) has been designed to measure the usability of a VR system according to the attitude and perception of its users. Important aspects of VR systems were carefully derived to produce key usability factors for the questionnaire. Unlike questionnaires designed for generic interfaces VRUSE is specifically designed to cater for evaluating virtual environments, being a diagnostic tool providing a wealth of information about a user's viewpoint of the interface. VRUSE can be used to great effect with other evaluation techniques to pinpoint problematical areas of a VR interface. Other applications include bench-marking of competitor VR systems.

Consumer Behavior↗

PubMed2005

From presence to consciousness through virtual reality.

Immersive virtual environments can break the deep, everyday connection between where our senses tell us we are and where we are actually located and whom we are with. The concept of 'presence' refers to the phenomenon of behaving and feeling as if we are in the virtual world created by computer displays. In this article, we argue that presence is worthy of study by neuroscientists, and that it might aid the study of perception and consciousness.

Computer Simulation↗

PubMed2003

Virtual reality provides leisure time opportunities for young adults with physical and intellectual disabilities.

Due to limitations in their physical abilities, adults with cerebral palsy (CP) have relatively few opportunities to engage in independent leisure activities. This pervasive lack of opportunity often leads to the development of dependent behavioral patterns and learned helplessness. The objective of this pilot study was to explore ways in which virtual reality can provide positive and enjoyable leisure experiences during physical interactions with different game-like virtual environments and potentially lead to increased self-esteem and a sense of self-empowerment. The study sample consisted of five young male adults with CP and severe intellectual disabilities who are non-speaking and who use wheelchairs for mobility. Each participant experienced three game-like virtual scenarios via VividGroup's Gesture Xtreme video capture virtual reality (VR) system. The participant's video captured image was processed on the same plane as screen graphical animations that react in real time in response to his movements. Outcome measures included the participants' responses to a five-item presence questionnaire, a 6-item task specific questionnaire and observation of their videotaped performance while participating in the virtual games. Participants' responses to the questionnaire showed a high level of presence in all three scenarios. These participants demonstrated an exceptional degree of enthusiasm during each VR experience; some reacted to the various stimuli via appropriate and goal-oriented responses, in other cases the response was more arbitrary. Documentation of behaviors during and following the VR experiences may provide insight into the important role that VR may play in nurturing their self-esteem and sense of empowerment.

Adult↗

PubMed1997

[Rationalizing the organization and structure of a trauma surgery clinic based on rationing of personal and financial resources--analysis, simulation and conversion using modern data processing techniques].

With a system of modeling, simulation, animation of information, communication in medicine (mosaic-m) the structures of organisation and information in a level 1 trauma center were analysed and animated as a virtual environment on screen in a first step. One result: in existing paper orientated documentation 50% of documentation was redundant. In a second step the requirements of the future information system were described systematically, user- and organisation-oriented. All components (hard- and software) were simulated an screen that the user could work virtually in the future working place. With mosaic-m the user is fully integrated in analysing and developing a new information system in the clinic.

Computer Simulation↗

PubMed2001

Strategic identities in cyberspace.

This paper aims at describing, according to the recent advances in social psychology and Computer Mediated Communication, how identities are perceived and constructed in cyberspace. All interactions analyzed in this study were performed within "Euroland," a collaborative virtual environment. The interacting community was composed of students, teachers, and researchers working on a transnational educational project. Practices and dialogues within Euroland are analyzed using an ethnographic and conversational method. A sample of discourses and actions that occurred during 8 months of time, selected according to the research aims, was analyzed. During online connections, users were personified by an "Avatar." Avatars are able to walk, fly, and look around the virtual world. They are also able to build and manipulate three-dimensional objects, perform virtual actions, and chat with other connected users. Results showed that "Eurolanders" showed and constructed their identities using strategic "positioning" depending on the interactive situation. Identities are thus dynamic and strongly related to the context, created and constantly recreated by the users. It is concluded that specific features offered by the Euroland environment are exploited by the users as resources to play with, while moving from one strategic positioning to another. Cyber identities involve resources given by specific technological tools and by community. The cyber-identity construction process seems to be highly congruent to the advances in the dialogical perspective in psychology, where identities are considered in their conceptualizations as multiple, "multivoiced," "positioned," and context-dependent.

Communication↗

PubMed2005

Vestibular, proprioceptive, and haptic contributions to spatial orientation.

The control and perception of body orientation and motion are subserved by multiple sensory and motor mechanisms ranging from relatively simple, peripheral mechanisms to complex ones involving the highest levels of cognitive function and sensory-motor integration. Vestibular contributions to body orientation and to spatial localization of auditory and visual stimuli have long been recognized. These contributions are reviewed here along with new insights relating to sensory-motor calibration of the body gained from space flight, parabolic flight, and artificial gravity environments. Recently recognized contributions of proprioceptive and somatosensory signals to the appreciation of body orientation and configuration are described. New techniques for stabilizing posture by means of haptic touch and for studying and modeling postural mechanisms are reviewed. Path integration, place cells, and head direction cells are described along with implications for using immersive virtual environments for training geographic spatial knowledge of real environments.

Cognition↗

PubMed2005

Personality of people using chat: an on-line research.

Conflicting claims have been presented in the literature about on-line management of personal relationships. The current research, carried out in a substantially descriptive design, aimed to consider psychological and social features of a particular electronic environment, the Chat room. One hundred fifty-eight participants filled out an on-line questionnaire set, designed to investigate the personality traits and the prevailing interpersonal values of those participants who set up interpersonal relationships on-line. The Web research showed that, if sampling control and validity assessment were provided, it could be a valid alternative to a more traditional paper-based procedure. The results highlighted that Chat users were not an homogenous group, but were composed of different personality types. Basically, however, this specific virtual environment proved to be crowded with rather close individuals, who were looking for independence but who needed also to be supported and encouraged. They created deep on-line relationships, but these remained limited to the virtual world.

Adolescent↗

PubMed2002

A maritime navigation display that provides visual feedback to improve conning officers' ship-handling during low visibility environments.

Navigating a ship at night in close proximity to another vessel is a dangerous task. To improve conning officers' night time ship-handling performance, a visual navigation display is proposed that is mounted on the stern of the aircraft carrier that will help shipboard conning officers manoeuvre in a battle group formation. To test the effectiveness of the visual navigation display, the Nimitz-class aircraft and plane guard vessel, a Ticonderoga-class cruiser, were modelled in a virtual environment. A navigation display condition had significantly fewer navigational positional errors than a non-navigation display condition. The navigation display provided immediate feedback as to whether the aircraft carrier had changed bearing or speed, thus enabling the operator to initiate the appropriate input to maintain station astern of the carrier. Actual or potential applications of this research include the deployment of a maritime navigation display to assist conning officers' ship handling.

Computer Graphics↗

PubMed1998

[Development of a surgical simulator for interventions of the paranasal sinuses. Technical principles and initial prototype].

BACKGROUND: Traditional training methods for surgeons include anatomical studies on human cadavers. Limited availability and ethical problems led to the consideration of alternatives. The surgeon's level of training could be significantly increased by a interactive training system trough computer graphics and virtual reality (VR). METHODS: Two main issues addressed are the 3-D reconstruction process and 3-D interaction to guide the surgical instruments. To provide the virtual environment, a realistic representation of the region of interest with all relevant anatomical parts is required. This model has to be suitable for computer simulation, while preserving as accurately as possible important anatomic features. Therefore the concept of creating a 3-D representation semi-automatically was developed. Textures derived from endoscopic images are superimposed on the virtual anatomic structures and provide better realism. RESULTS: Intuitive handling of the surgical instruments is ensured by using the tracking technique. The system allows navigation via a virtual camera and interaction with the virtual anatomical structures. Currently the use of a force feedback system and the simulation of deformations of tissues is critical. CONCLUSIONS: The VR based simulation system offers an alternative to conventional training methods. The future role of surgical simulation depends on overcoming the current drawbacks to provide greater interactive realism: the integration of a force feedback system to simulate the resistance of anatomical structures and the simulation of tissue deformations--both currently under development.

Artificial Intelligence↗

PubMedDate not supplied

Image-based collision detection for deformable cloth models.

Modeling the natural interaction of cloth and garments with objects in a 3D environment is currently one of the most computationally demanding tasks. These highly deformable materials are subject to a very large number of contact points in the proximity of other moving objects. Furthermore, cloth objects often fold, roll, and drape within themselves, generating a large number of self-collision areas. The interactive requirements of 3D games and physically driven virtual environments make the cloth collisions and self-collision computations more challenging. By exploiting mathematically well-defined smoothness conditions over smaller patches of deformable surfaces and resorting to image-based collision detection tests, we developed an efficient collision detection method that achieves interactive rates while tracking self-interactions in highly deformable surfaces consisting of a large number of elements. The method makes use of a novel technique for dynamically generating a hierarchy of cloth bounding boxes in order to perform object-level culling and image-based intersection tests using conventional graphics hardware support. An efficient backward voxel-based AABB hierarchy method is proposed to handle deformable surfaces which are highly compressed.

Journal Article↗

PubMed2004

Male sexual dysfunctions: immersive virtual reality and multimedia therapy.

The study describes a therapeutic approach using psycho-dynamic psychotherapy integrating virtual environment (VE) for resolving impotence or better erectile dysfunction (ED) of presumably psychological or mixed origin and premature ejaculation (PE). The plan for therapy consists of 12 sessions (15 if a sexual partner was involved) over a 25-week period on the ontogenetic development of male sexual identity, and the methods involved the use of a laptop PC, joystick, Virtual Reality (VR) helmet with miniature television screen showing a new specially-designed CD-ROM programs using Virtools with Windows 2000 and an audio CD. This study was composed of 30 patients, 15 (10 suffering from ED and 5 PE) plus 15 control patients (10 ED and 5 PE), that underwent the same therapeutic protocol but used an old VR helmet to interact with the old VE using a PC Pentium 133 16 Mb RAM. We also compared this study with another study we carried out on 160 men affected by sexual disorders, underwent the same therapeutic protocol, but treated using a VE created (in Superscape VRT 5.6) using always Windows 2000 with portable tools. Comparing the groups of patients affected by ED and PE, there emerged a significant positive results value without any important differences among the different VE used. However, we had a % increase of undesirable physical reactions during the more realistic 15-minute VR experience using Virtools development kit. Psychotherapy alone normally requires long periods of treatment in order to resolve sexual dysfunctions. Considering the particular way in which full-immersion VR involves the subject who experiences it (he is totally unobserved and in complete privacy), we hypothesise that this methodological approach might speed up the therapeutic psycho-dynamic process, which eludes cognitive defences and directly stimulates the subconscious, and that better results could be obtained in the treatment of these sexual disorders. This method can be used by any psychotherapist and it can be used alone or associated with pharmacotherapy prescribed by the urologist/andrologist as part of a therapeutic alliance.

CD-ROM↗

PubMed2006

Seeing ahead: experience and language in spatial perspective.

Spatial perspective can be directed by various reference frames, as well as by the direction of motion. In the present study, we explored how ambiguity in spatial tasks can be resolved. Participants were presented with virtual reality environments in order to stimulate a spatialreference frame based on motion. They interacted with an ego-moving spatial system in Experiment 1 and an object-moving spatial system in Experiment 2. While interacting with the virtual environment, the participants were presented with either a question representing a motion system different from that of the virtual environment or a nonspatial question relating to physical features of the virtual environment. They then performed the target task assign the label front in an ambiguous spatial task. The findings indicate that the disambiguation of spatial terms can be influenced by embodied experiences, as represented by the virtual environment, as well as by linguistic context.

Adolescent↗

PubMed2006

Image-guided laser projection for port placement in minimally invasive surgery.

We present an application of an augmented reality laser projection system in which procedure-specific optimal incision sites, computed from pre-operative image acquisition, are superimposed on a patient to guide port placement in minimally invasive surgery. Tests were conducted to evaluate the fidelity of computed and measured port configurations, and to validate the accuracy with which a surgical tool-tip can be placed at an identified virtual target. A high resolution volumetric image of a thorax phantom was acquired using helical computed tomography imaging. Oriented within the thorax, a phantom organ with marked targets was visualized in a virtual environment. A graphical interface enabled marking the locations of target anatomy, and calculation of a grid of potential port locations along the intercostal rib lines. Optimal configurations of port positions and tool orientations were determined by an objective measure reflecting image-based indices of surgical dexterity, hand-eye alignment, and collision detection. Intra-operative registration of the computed virtual model and the phantom anatomy was performed using an optical tracking system. Initial trials demonstrated that computed and projected port placement provided direct access to target anatomy with an accuracy of 2 mm.

Canada↗

PubMed2002

Temporal information for spatially constrained locomotion.

How is locomotion adapted to spatial environmental constraints? The control of this everyday behavior is claimed to be based on information that specifies either spatial or temporal properties of the actor-environment system. Although studies on open-loop locomotor pointing (i.e., the positioning of a foot on a target on the floor while walking) agree on the use of spatial information, studies on closed-loop locomotor pointing propose the use of temporal information. Here, we test the hypothesis of closed-loop locomotor pointing based on temporal information, by dissociating spatial and temporal information in a virtual reality setup (virtual environment connected to a treadmill). The results support this hypothesis and shed some light on the type of temporal information that is used. The performed dissociation between spatial and temporal information, however, does not rule out a control based on a continuous updating of spatial information. Therefore, our conclusion on the use of temporal information was moderated.

Adaptation, Physiological↗

PubMed2002

Ethical codes and values in a virtual world.

Some members of the so-called virtual world deny that technology such as the virtual environment (VE) is value-laden. But there are a variety of complex issues which arise in VE that make it necessary to think about ethics and values in VE applications. Using VE in therapy and psychotherapy research or diagnostics leads to several ethical concerns. VE can impoverish those aspects of life that are essential to social development, interpersonal relations, and emotional growth. This paper will focus on the concept called "virtual world," a question of metaphysics. After reviewing general ethical principles, ethics in applied sciences will be described. Ethical decision-making, code of conduct, and specific issues in VE will be discussed. The VE community is challenged to set guidelines around VE, and its ethics and values. A set of measurement tools around ethical codes and values in a virtual world ought to be discursively gained in this virtual world and in real society as a whole.

Bioethics↗