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At least 253 records · Page 14Linked to original sources

PubMed2006

Virtual environment-based training simulator for endoscopic third ventriculostomy.

A virtual environment-based endoscopic third ventriculostomy simulator is being developed for training neurosurgeons as a standardized method for evaluating competency. Magnetic resonance (MR) images of a patient's brain are used to construct the geometry model, realistic behavior in the surgical area is simulated by using physical modeling and surgical instrument handling is replicate by a haptic interface. The completion of the proposed virtual training simulator will help the surgeon to practice the techniques repeatedly and effectively, serving as a powerful educational tool.

Computer Simulation↗

PubMed1997

WWW creates new interactive 3D graphics and collaborative environments for medical research and education.

Virtual Reality Modelling Language (VRML) is the start of a new era for medicine and the World Wide Web (WWW). Scientists can use VRML across the Internet to explore new three-dimensional (3D) worlds, share concepts and collaborate together in a virtual environment. VRML enables the generation of virtual environments through the use of geometric, spatial and colour data structures to represent 3D objects and scenes. In medicine, researchers often want to interact with scientific data, which in several instances may also be dynamic (e.g. MRI data). This data is often very large and is difficult to visualise. A 3D graphical representation can make the information contained in such large data sets more understandable and easier to interpret. Fast networks and satellites can reliably transfer large data sets from computer to computer. This has led to the adoption of remote tale-working in many applications including medical applications. Radiology experts, for example, can view and inspect in near real-time a 3D data set acquired from a patient who is in another part of the world. Such technology is destined to improve the quality of life for many people. This paper introduces VRML (including some technical details) and discusses the advantages of VRML in application developing.

Computer Communication Networks↗

PubMedDate not supplied

The role of virtual reality technology in the assessment and training of inexperienced powered wheelchair users.

PURPOSE: The current paper provides quantitative and qualitative data concerning the application of two virtual environments to the assessment and training of inexperienced powered wheelchair users, both in terms of the ability to control the chair accurately without hitting objects in the environment (manoeuvrability) and in terms of being able to find ones way around a complex environment without becoming lost (route-finding). METHOD: Six novice powered wheelchair users participated in the project, completing either the manoeuvrability or route finding components of the study. Performance measures were taken in real life pre and post training and throughout virtual reality sessions. Participants also completed a questionnaire regarding the aesthetics of the virtual environments and aspects of the powered wheelchair simulation. RESULTS: The participants rated the aesthetics of the virtual environments positively and engaged well with the virtual system. However, they found the manoeuvrability tasks considerably more difficult in virtual reality (VR) than in real life. Some difficulties with controlling the simulated wheelchair were apparent. Some improvements on virtual and real life manoeuvrability tasks and route finding were noted following conventional and virtual training. CONCLUSIONS: The study indicated that the two virtual environments represent a potentially useful means of assessing and training novice powered wheelchair users. The virtual environments however must become less challenging if they are to represent a motivating and effective means of improving performance. Further development of the way in which wheelchair movement is controlled and simulated represents a key element in this multi stage project.

Adult↗

PubMed2006

Student perceptions of a virtual learning environment for a problem-based learning undergraduate medical curriculum.

OBJECTIVE: To investigate the effects of a virtual learning environment (VLE) on group interaction and consultation of information resources during the preliminary phase, self-study phase and reporting phase of the problem-based learning process in an undergraduate medical curriculum. METHODS: A questionnaire was administered to 355 medical students in Years 1 and 2 to ask them about the perceived usefulness of a virtual learning environment that was created with Blackboard for group interaction and the use of learning resources. RESULTS: The students indicated that the VLE supported face-to-face interaction in the preliminary discussion and in the reporting phase but did not stimulate computer-mediated distance interaction during the self-study phase. They perceived that the use of multimedia in case presentations led to a better quality of group discussion than if case presentations were exclusively text-based. They also indicated that the information resources that were hyperlinked in the VLE stimulated the consultation of these resources during self-study, but not during the reporting phase. CONCLUSIONS: Students indicated that the use of a VLE in the tutorial room and the inclusion of multimedia in case presentations supported processes of active learning in the tutorial groups. However, if we want to exploit the full potential of asynchronous computer-mediated communication to initiate in-depth discussion during the self-study phase, its application will have to be selective and deliberate. Students indicated that the links in the VLE to selected information in library repositories supported their learning.

Attitude of Health Personnel↗

PubMed2004

Simulator sickness when performing gaze shifts within a wide field of view optic flow environment: preliminary evidence for using virtual reality in vestibular rehabilitation.

BACKGROUND: Wide field of view virtual environments offer some unique features that may be beneficial for use in vestibular rehabilitation. For one, optic flow information extracted from the periphery may be critical for recalibrating the sensory processes used by people with vestibular disorders. However, wide FOV devices also have been found to result in greater simulator sickness. Before a wide FOV device can be used in a clinical setting, its safety must be demonstrated. METHODS: Symptoms of simulator sickness were recorded by 9 healthy adult subjects after they performed gaze shifting tasks to locate targets superimposed on an optic flow background. Subjects performed 8 trials of gaze shifting on each of the six separate visits. RESULTS: The incidence of symptoms of simulator sickness while subjects performed gaze shifts in an optic flow environment was lower than the average reported incidence for flight simulators. The incidence was greater during the first visit compared with subsequent visits. Furthermore, the incidence showed an increasing trend over the 8 trials. CONCLUSION: The performance of head unrestrained gaze shifts in a wide FOV optic flow environment is tolerated well by healthy subjects. This finding provides rationale for testing these environments in people with vestibular disorders, and supports the concept of using wide FOV virtual reality for vestibular rehabilitation.

Journal Article↗

PubMed2006

A surgical and fine-motor skills trainer for everyone? Touch and force-feedback in a virtual reality environment for surgical training.

Access to the laboratory component of a class is limited by resources, while lab training is not currently possible for distance learning. To overcome the problem a solution is proposed to enable hands-on, interactive, objectively scored and appropriately mentored learning in a widely accessible environment. The proposed solution is the Virtual-Reality Motor-Skills trainer to teach basic fine-motor skills using Haptics for touch and feel interaction as well as a 3D virtual reality environment for visualization.

Computer Simulation↗

PubMed2003

[The use of virtual learning environment in teaching basic and advanced life support].

The present paper is the result of an experiment conducted as part of the Nursing: basic and advanced life support course, which was offered as a semi-online course using the virtual learning environment called Learning Space. The virtual learning environment optimizes classroom dynamics, since in the classroom setting, practical activities may be privileged; besides, learning is customized as students may access the environment whenever and wherever they wish.

Computer-Assisted Instruction↗

PubMed2002

Virtual reality assisted cognitive behavioral therapy for the treatment of Panic Disorders with Agoraphobia.

The chapter describes the characteristics of the Experiential-Cognitive Therapy (ECT) protocol for Panic Disorder and Agoraphobia. The goal of ECT is to decondition fear reactions, to modify misinterpretational cognition related to panic symptoms and to reduce anxiety symptoms. This is possible in an average of eight sessions of treatment plus an assessment phase and booster sessions, through the integration of Virtual Experience and traditional cognitive-behavioral techniques. We decided to employ the techniques included in the cognitive-behavioral approach because they showed high levels of efficacy. Through virtual environments we can gradually expose the patient to feared situation: virtual reality consent to re-create in our clinical office a real experiential world. The patient faces the feared stimuli in a context that is nearer to reality than imagination. For ECT we developed the Virtual Environments for Panic Disorders--VEPD--virtual reality system. VEPD is a 4-zone virtual environment developed using the Superscape VRT 5.6 toolkit. The four zones reproduce different potentially fearful situations--an elevator, a supermarket, a subway ride, and large square. In each zone the characteristics of the anxiety-related experience are defined by the therapist through a setup menu.

Agoraphobia↗

PubMed2001

Place learning in virtual space. III: Investigation of spatial navigation training procedures and their application to fMRI and clinical neuropsychology.

This paper describes the utilization of a desktop virtual environment task, the Computer-Generated (C-G) Arena, in the study of human spatial navigation. First, four experiments examined the efficacy of various training procedures in the C-G Arena. In Experiment 1, participants efficiently located a hidden target after only observing the virtual environment from a fixed position (placement learning). In Experiment 2, participants efficiently located a hidden target after only observing an experimenter search the virtual environment (observational learning). In Experiment 3, participants failed to display a latent learning effect in the virtual environment. In Experiment 4, all training procedures effectively taught participants the layout of the virtual environment, but the observational learning procedure most effectively taught participants the location of a hidden target within the environment. Finally, two experiments demonstrated the application of C-G Arena procedures to neuroimaging (Experiment 5) and neuropsychological (Experiment 6) investigations of human spatial navigation.

Adolescent↗

PubMed1994

Dissociating visual and kinesthetic coordinates during pointing movements.

Goal-directed movements imply that the visual coordinates in which the localisation of the goal is coded are transformed into proprioceptive coordinates in which the arm movement is coded. The two systems of coordinates are normally superimposed. Using a virtual reality device attached to the subject's head, we have created a situation where these systems were dissociated from each other. The virtual environment involved virtual visual targets and an image of the subject's hand reconstructed from the output of a data glove wore by the subject's right hand. When the subject's head was rotated, the visual targets and the image of the hand rotated by the same amount. Movements of the real hand were thus in conflict with those of the reconstructed hand, which appeared to err in the direction of head rotation. Pointing movements directed at five targets (0 degree, 26 degrees and 52 degrees on each side) were studied for five different head positions (0 degree, 45 degrees and 80 degrees to the right and to the left). The results showed a significant pointing bias towards head position, except for the left-most targets in the right head rotations. Constant errors in azimuth were proportional to the amount of head rotation. When the head was rotated to the right, constant errors in azimuth were greater during pointing towards right than left targets. Similarly, they were greater for left than for right stimuli when the head was rotated to the left. Errors in amplitude were not influenced by the direction nor the amount of head rotation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2006

Developing a multimedia environment for customized teaching of an adrenalectomy.

We have developed a computer based simulation process which allows a surgical expert to create a customized operative environment. This virtual environment, the Toolkit for Illustration of Procedures in Surgery (3D TIPS), is deployed on a low-cost computer system and requires minimal training for the programmer. The learner can be engaged in training immediately and the educator can modify the system and annotate the procedure to highlight specific points using video clips, operative images, and the like. A laparoscopic adrenalectomy is presented as a proof of concept in the accompanying article.

Adrenalectomy↗

PubMed2006

Availability of a virtual learning environment does not compensate for the lack of a physical facility.

A virtual learning environment (VLE), including access to on-line journals, was set up in support of a new medical curriculum delivered at two campuses. We evaluated student perceptions and use of the VLE including the library facilities using several qualitative and quantitative data methods and the results were triangulated. Paper copies of set texts are provided at each site; however, one site also has a traditional library for the training of professions allied to medicine. As the teaching was identical at each site, this gave us the opportunity for a study exploring the effect of having a physical library facility on the use of the VLE. Although ten-fold more loans were made from the library with the medical sources than from the other site, use of the VLE was very similar at both sites, suggesting that reduced access to hard copy books and journals was not compensated for by increased use of electronic library resources. As expected, training, ease of navigation and access to the VLE were very important to student satisfaction.

Computer-Assisted Instruction↗

PubMed2004

Stereopsis in medical virtual-learning-environments.

In surgical training a lot of effort is directed at developing virtual learning environments (VLE's). These environments usually include one or more of the following features: haptic feedback, the sending of a slightly different computer-generated image to both eyes (affording an user's experience of stereoptical depth), and a transparant interface that allows 'natural' interaction. Now that many of these VLE's are approaching a state of maturity, time has come to start evaluating these environments, as basic questions regarding the effectiveness of the features mentioned above remain unanswered. The purpose of this article is to present an experiment aimed at evaluating the effects of stereopsis during a learning phase on visuo-spatial reasoning in two subsequent tasks that are related to the medical practice of diagnosis.

Clinical Competence↗

PubMedDate not supplied

Scalable WIM: effective exploration in large-scale astrophysical environments.

Navigating through large-scale virtual environments such as simulations of the astrophysical Universe is difficult. The huge spatial range of astronomical models and the dominance of empty space make it hard for users to travel across cosmological scales effectively, and the problem of wayfinding further impedes the user's ability to acquire reliable spatial knowledge of astronomical contexts. We introduce a new technique called the scalable world-in-miniature (WIM) map as a unifying interface to facilitate travel and wayfinding in a virtual environment spanning gigantic spatial scales: Power-law spatial scaling enables rapid and accurate transitions among widely separated regions; logarithmically mapped miniature spaces offer a global overview mode when the full context is too large; 3D landmarks represented in the WIM are enhanced by scale, positional, and directional cues to augment spatial context awareness; a series of navigation models are incorporated into the scalable WIM to improve the performance of travel tasks posed by the unique characteristics of virtual cosmic exploration. The scalable WIM user interface supports an improved physical navigation experience and assists pragmatic cognitive understanding of a visualization context that incorporates the features of large-scale astronomy.

Journal Article↗

PubMed1998

From toy to tool: the development of immersive virtual reality environments for psychotherapy of specific phobias.

Virtual Reality (VR) entered the mental health field some years ago. While the technology itself has been available for more than ten years now, there is still a certain amount of uncertainty among researchers and users as to whether VR will one day fulfill all it's promises. In this chapter we are giving an overview of the implementation of the technology in our mental health research facility in Basel, Switzerland. The development of two applications for use with claustrophobic and acrophobic patients perspectively serves just as an example within this context. Some may say, the chapter is too much based on technical considerations. Strictly speaking, VR is pure technology, even knowing that this special form of technology has sensory, psychological and even philosophical implications not known from other human computer interfaces so far. As far as we are concerned, the development of the technology for use within the mental health sector has merely just begun. As today's mostly used immersive output devices (Head-mounted Displays, shutter glasses) do not have a satisfactory resolution, do restrict movements and prevent multi-user-capabilities, there will be a soar of mental health applications the day some or at least the most important of these obstacles have been overcome.

Computer Simulation↗

PubMed2006

Advancing of Russian ChemBioGrid by bringing Data Management tools into collaborative environment.

Virtual organizations of researchers need effective tools to work collaboratively with huge sets of heterogeneous data distributed over HealthGrid. This paper describes a mechanism of supporting Digital Libraries in High-Performance Computing environment based on Grid technology. The proposed approach provides abilities to assemble heterogeneous data from distributed sources into integrated virtual collections by using OGSA-DAI. The core of the conception is a Repository of Meta-Descriptions that are sets of metadata which define personal and collaborative virtual collections on base of virtualized information resources. The Repository is kept in a native XML-database Sedna and is maintained by Grid Data Services.

Cooperative Behavior↗

PubMed2005

Spatiotemporal gait deviations in a virtual reality environment.

Previous research suggests that postural sway in standing increases in virtual reality (VR) environments. This study was conducted to examine whether gait instability is prevalent when people walk in a VR environment. Ten healthy adults participated in the study. Subjects walked on a treadmill in a VR environment and a non-VR environment at each of three walking speeds: 0.9, 1.1, and 1.3 m/s. In the VR environment, an endless corridor with colored vertical stripes comprising the walls was projected onto a hemispherical screen placed in front of the treadmill. The speed of the moving corridor image was matched to the speed of the treadmill to create the illusion that subjects were walking through the endless corridor. Spatiotemporal data during gait were collected with an instrumented treadmill housing two piezoelectric force platforms. Gait parameters reflective of gait instability (stride length, step width, variability in stride velocity, and variability in step width) were compared between the VR and non-VR environments. Subjects walked in the VR environment with reduced stride lengths (p = 0.001), increased step widths (p = 0.001), and with increased variability in stride velocity (p < 0.001) and step width (p = 0.002). The gait deviations suggest that walking in a VR environment may induce gait instability in healthy subjects.

Adult↗

PubMed2001

The development of the virtual reality system for the treatment of the fears of public speaking.

The fear of public speaking is a kind of social phobias. The patients having the fear of public speaking show some symptoms like shame and timidity in the daily personal relationship. They are afraid that the other person would be puzzled, feel insulted, and they also fear that they should be underestimated for their mistakes. For the treatment of the fear of public speaking, the cognitive-behavioral therapy has been generally used. The cognitive-behavioral therapy is the method that makes the patients gradually experience some situations inducing the fears and overcome those at last. Recently, the virtual reality technology has been introduced as an alternative method for providing phobic situations. In this study, we developed the public speaking simulator and the virtual environments for the treatment of the fear of public speaking. The head-mounted display, the head-tracker and the 3 dimensional sound system were used for the immersive virtual environment. The imagery of the virtual environment consists of a seminar room and 8 virtual audiences. The patient will speak in front of these virtual audiences and the therapist can control motions, facial expressions, sounds, and voices of each virtual audience.

Cognitive Behavioral Therapy↗