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PubMed2005

The menstrual cycle and susceptibility to virtual simulation sickness.

Virtual simulation sickness (VSS) is a form of visually induced motion sickness that can result from immersion in a virtual environment (VE). As in their susceptibility to the sickness induced by real motion, women have been reported to be more susceptible than men to VSS, yet the reason for this difference is not known. The aim of the current study was to investigate the influence of the menstrual cycle on susceptibility to VSS in 16 naturally cycling women and to compare the responses of this group with control groups consisting of 1) 16 premenopausal women taking a combined monophasic oral contraceptive and 2) 16 men. All female participants were immersed in a nauseogenic VE on days 5, 12, 19, and 26 of their menstrual/pill cycle. These days were chosen because they fall in line with peaks and troughs of ovarian hormone levels. Menstrual cycle phase was confirmed by salivary estradiol and progesterone levels. A 4-week "pseudo-cycle" was assigned to the male participants. Hormone analysis revealed that 9 participants in the experimental group had been tested at the desired phases of their cycle. These participants exhibited a significant increase in susceptibility to VSS on day 12 of their cycle. The hormone analysis also showed that the cycles of the 7 remaining members of the experimental group had not precisely followed the expected pattern, and so these people had been tested on days that did not coincide with peaks and troughs of ovarian hormone levels. No consistent variation in susceptibility was observed over the cycle in these volunteers. In addition, no change in susceptibility was observed over the pill cycle of the oral contraceptive group nor over the pseudo-cycle applied to the male control group. The authors conclude that susceptibility to VSS varies over the menstrual cycle as a consequence of hormonal variation.

Adult↗

PubMed2002

e-Community health nursing.

Dissolving boundaries of space and time, the Internet creates another dimension in which to practice community health nursing. Addressing the challenges of health issues in the virtual environment affords new opportunities for holistic nursing practice. Grounded in holistic nursing theory and practice and built on a feminist foundation, this article explores the process of community health nursing within an Internet-based community. A brief review of the literature identifies relevant research findings. Barriers to communication are identified. These include perceived ease of use of computer technology and gendered patterns of communication. Lessons learned in an actual Internet community are discussed.

Communication↗

PubMed2006

Simulation for training with the Autosuture Endo Stitch device.

The rapid development and deployment of novel laparoscopic instruments present the surgical educator and trainee with a significant challenge. Several useful instruments have been particularly difficult to teach the novice. We have developed a platform that allows the combination of the actual instrument handle with a virtual re-creation of the instrument tip. We chose the Autosuture Endo Stitch device as the prototypical instrument because it satisfies our subjective experience of "useful, but hard to teach." A software package was developed to support the re-creation of the needle and suture that accompany the device. The apparatus has haptic capabilities and collision detection so that the needle driver is "aware" of suture and instrument contact. The developed virtual environment allows re-creation of the necessary motion to simulate the instrument, the trainee can use the actual instrument handle, and the system can be altered to accommodate other instruments.

Algorithms↗

PubMed1996

Target detection performance in helmet-mounted and conventional dome displays.

An experiment was conducted to assess visual target detection performance using a helmet-mounted display (HMD) and a conventional flight simulation dome display. Measures of workload and mood were also obtained. Participants in both viewing conditions scanned an area 120 degrees vertical by 240 degrees horizontal while attempting to locate targets that appeared to be approaching them from one of a possible 18 locations. Results indicated significantly superior performance in the conventional dome display. Workload and mood measures also showed a significant advantage for the dome display. Results are discussed in terms of their implications for the design and use of HMD systems as components of airborne virtual environment interfaces.

Adult↗

PubMed1998

The use of electronic mail at the reference desk: impact of a computer-mediated communication technology on librarian-client interactions.

Commonly recognized computer-mediated communication (CMC) tools include virtual environments, bibliographic databases, listservers, newsgroups, group teleconferencing, interactive messaging systems and electronic mail. The use of these technologies in libraries has grown exponentially over the past decade. Electronic mail has emerged as an especially popular communication tool for librarians, and their colleagues and patrons. This paper explores the use of a reference department electronic mail service and its impact on reference services and librarian-client interactions. Several issues related to the implementation of CMC technologies are presented, including the maintenance and monitoring of reference electronic mail systems, the types of questions that are typically posted, and potential barriers to the implementation and use of reference e-mail.

Academic Medical Centers↗

PubMed2003

From biophysics to behavior: Catacomb2 and the design of biologically-plausible models for spatial navigation.

A variety of approaches are available for using computational models to help understand neural processes over many levels of description, from sub-cellular processes to behavior. Alongside purely deductive bottom-up or top-down modeling, a systems design strategy has the advantage of providing a clear goal for the behavior of a complex model. The order in which biological details are added is dictated by functional requirements in terms of the tasks that the model should perform. Ideas from engineering can be mixed with those from biology to build systems in which some constituents are modeled in detail using biologically-realistic components, while others are implemented directly in software. This allows the areas of most interest to be studied within the context of a behaving system in which each component is constrained both by the biology it is intended to represent as well as the task it is required to perform within the system. The Catacomb2 modeling package has been developed to allow rapid and flexible design and study of complex multi-level systems ranging in scale from ion channels to whole animal behavior. The methodology, internal architecture, and capabilities of the system are described. Its use is illustrated by a modeling case study in which hypotheses about how parahippocampal and hippocampal structures may be involved in spatial navigation tasks are implemented in a model of a virtual rat navigating through a virtual environment in search of a food reward. The model incorporates theta oscillations to separate encoding from retrieval and yields testable predictions about the phase relations of spiking activity to theta oscillations in different parts of the hippocampal formation at various stages of the behavioral task.

Algorithms↗

PubMed2006

The boundary vector cell model of place cell firing and spatial memory.

We review evidence for the boundary vector cell model of the environmental determinants of the firing of hippocampal place cells. Preliminary experimental results are presented concerning the effects of addition or removal of environmental boundaries on place cell firing and evidence that boundary vector cells may exist in the subiculum. We review and update computational simulations predicting the location of human search within a virtual environment of variable geometry, assuming that boundary vector cells provide one of the input representations of location used in mammalian spatial memory. Finally, we extend the model to include experience-dependent modification of connection strengths through a BCM-like learning rule - the size and sign of strength change is influenced by historic activity of the postsynaptic cell. Simulations are compared to experimental data on the firing of place cells under geometrical manipulations to their environment. The relationship between neurophysiological results in rats and spatial behaviour in humans is discussed.

Action Potentials↗

PubMed2000

The framing of drivers' route choices when travel time information is provided under varying degrees of cognitive load.

In two experiments, participants chose between staying on a main route with a certain travel time and diverting to an alternative route that could take a range of travel times. In the first experiment, travel time information was displayed on a sheet of paper to participants seated at a desk. In the second experiment, the same information was displayed in a virtual environment through which participants drove. Overall, participants were risk-averse when the average travel time along the alternative route was shorter than the certain travel time of the main route but risk-seeking when the average travel time of the alternative route was longer than the certain travel time along the main route. In the second experiment, in which cognitive load was higher, participants simplified their decision-making strategies. A simple probabilistic model describes the risk-taking behavior and the load effects. Actual or potential applications of this research include the development of efficient travel time information systems for drivers.

Adult↗

PubMed2000

Postural instability and motion sickness in a fixed-based flight simulator.

We evaluated the prediction that postural instability would precede the subjective symptoms of motion sickness in a fixed-base flight simulator. Participants sat in a cockpit in a video projection dome and were exposed to optical flow that oscillated in the roll axis with exposure durations typical of flight simulation. The frequencies of oscillation were those that characterize spontaneous postural sway during stance. Head motion was measured prior to and during exposure to imposed optical flow. Of 14 participants, 6 were classified as motion sick, either during or after exposure to the optical oscillation. Prior to the onset of subjective symptoms, head motion among participants who later became sick was significantly greater than among participants who did not become motion sick. We argue that the results support the postural instability theory of motion sickness. Actual or potential applications include the prevention or mitigation of motion sickness in virtual environments.

Adult↗

PubMed2001

Spatial representations of virtual mazes: the role of visual fidelity and individual differences.

Twenty-four people learned three versions of a room-sized maze: a wire-frame desktop virtual environment (VE), a normal surface-rendered desktop VE, and a real-world maze. Differences among the mental representations formed from each environment were measured with pointing and distance estimation tasks in a real-world version of each maze. People were more accurate at pointing after having learned the real and wire-frame VE maze than the surface-rendered VE maze; however, this effect was small compared with the effect of individual differences. Differences in gender, spatial ability, and prior computer experience were significantly related to the ability to acquire spatial information from the desktop VE. There was a high correlation between spatial knowledge when it was measured in the VE and spatial knowledge measured in the real world. Actual or potential applications include the design of effective VE training systems.

Adolescent↗

PubMed2002

Using tactile features to help functionally blind individuals denominate banknotes.

This study, which was conducted for the Bank of Canada, assessed the feasibility of presenting a raised texture feature together with a tactile denomination code on the next Canadian banknote series ($5, $10, $20, $50, and $100). Adding information accessible by hand would permit functionally blind individuals to independently denominate banknotes. In Experiment 1, 20 blindfolded, sighted university students denominated a set of 8 alternate tactile feature designs. Across the 8 design series, the proportion of correct responses never fell below .97; the mean response time per banknote ranged from 11.4 to 13.1 s. In Experiment 2, 27 functionally blind participants denominated 4 of the previous 8 candidate sets of banknotes. The proportion of correct responses never fell below .92; the corresponding mean response time per banknote ranged from 11.7 to 13.0 s. The Bank of Canada selected one of the four raised-texture designs for inclusion on its new banknote series. Other potential applications include designing haptic displays for teleoperation and virtual environment systems.

Adult↗

PubMed2006

Effects of displacement magnitude and direction of auditory cues on auditory spatial facilitation of visual search.

OBJECTIVE: The objective of this study is to examine the effects of cue error on auditory spatial facilitation (ASF) of visual search. BACKGROUND: ASF is the reduction in time needed to locate and identify a visual target when an auditory cue is presented at the location of the target. Although ASF has been shown to occur when the auditory cue coincides with the target location, it is important to determine whether facilitatory effects are also evident when the cue is displaced. METHOD: Participants performed a visual search task in the presence of an auditory cue that was presented at the center of the screen (uninformative), at the location of the target (accurate), or displaced up to 12 degrees from the target horizontally or vertically. RESULTS: Generally, displaced auditory cues reduced search times as compared with a condition in which the cue was uninformative. When the displacement was always along a single spatial dimension, the cue was as effective as a coincident cue if it was within the local visual area. However, when the dimension along which the cue was displaced varied randomly, the cue did not necessarily reduce search time and hurt performance when the visual search task was difficult. CONCLUSION: Designers of virtual audio displays should be aware that auditory cue accuracy will be affected by the difficulty of the visual task and the operators' knowledge of cue precision and reliability. APPLICATION: Findings from this study can be applied to the design of multimodal interfaces and augmented or virtual environments.

California↗

PubMed1998

Effects of localized auditory information on visual target detection performance using a helmet-mounted display.

An experiment was conducted to evaluate the effects of localized auditory information on visual target detection performance. Visual targets were presented on either a wide field-of-view dome display or a helmet-mounted display and were accompanied by either localized, nonlocalized, or no auditory information. The addition of localized auditory information resulted in significant increases in target detection performance and significant reductions in workload ratings as compared with conditions in which auditory information was either nonlocalized or absent. Qualitative and quantitative analyses of participants' head motions revealed that the addition of localized auditory information resulted in extremely efficient and consistent search strategies. Implications for the development and design of multisensory virtual environments are discussed. Actual or potential applications of this research include the use of spatial auditory displays to augment visual information presented in helmet-mounted displays, thereby leading to increases in performance efficiency, reductions in physical and mental workload, and enhanced spatial awareness of objects in the environment.

Adult↗

PubMed2006

[Development, implementation and evaluation of a distance course about wound treatment].

This research aimed to design, implement and evaluate a distance learning course (DLC), using the Internet, in a virtual environment named TelEduc. Thirty-eight nurses were invited, 28 of whom registered and 17 concluded the course. The specialists and the students evaluated the course and diagnostic (pre-test), process and final (post-test) evaluations were made. Specialists in distance learning and wounds considered the course as adequate but recommended minor adjustments. Most of the students showed a positive opinion about the course. A comparison between pre- and post-test results showed that students scored better on the post-test (p<0.0001). The course reached its objectives, although some adjustments are needed.

Achievement↗

PubMedDate not supplied

Video-capture virtual reality system for patients with paraplegic spinal cord injury.

This article presents results from a feasibility study of a video-capture virtual reality (VR) system used with patients who have paraplegic spinal cord injury (SCI) and who need balance training. The advantages of the VR system include providing the user with natural control of movements, the ability to use as many parts of the body as are deemed suitable within the context of therapeutic goals, and flexibility in the way the system can be adapted to suit specific therapeutic objectives. Thirteen participants with SCI experienced three virtual environments (VEs). Their responses to a Short Feedback Questionnaire showed high levels of presence. We compared performance in the environments with a group of 12 nondisabled participants. Response times for the patient group were significantly higher and percentage of success was significantly lower than that for the nondisabled group. In addition, significant moderate correlations were found between performance within a VE and static balance ability as measured by the Functional Reach Test. This study is a first step toward future studies aimed at determining the potential of using this VR system during the rehabilitation of patients with SCI.

Activities of Daily Living↗

PubMedDate not supplied

A Web-based distance education course in nutrition in public health: case study.

BACKGROUND: Strict work timetables, personal and professional duties or an inability to be absent from home or work can all represent major constraints for those wishing to improve their professional skills. Within this context, the World Wide Web can allow people to conveniently follow distance courses from their homes. OBJECTIVE: To present an experience in the use of the Web in the continuing education of healthcare professionals in Brazil. METHODS: A Web-based distance education course in nutrition in public health was developed. The methodology was an adaptation of both problem-based and task-based learning. At the end of the course an evaluation questionnaire which covered the course s contents, the educational methodology and resources, the duration and schedule, and the use of the Web as a tool for distance education was given to the students. RESULTS: There were 83 on line registrations from 13 states, 73 of the applicants were female, 62 had a degree in nutrition and 18 were physicians. From these; eleven students from ten states were chosen: nine female nutritionists, two female physicians, and one male physician. Seven students completed the course, took and passed the final exam. Of the other four students, two failed to follow the schedule, one had health problems, and one did not obtain the minimal score for sitting the final exam. The students had a mean age of 35, and a mean of ten years in practice. They all stated that they were unable to attend a regular course, even though they felt that they needed to improve their professional skills. Most of them studied seven days a week for between two and four hours a day. The students also felt that their professional skills had improved and each reported having made changes in their practice as a result of their participation. The students approved of the course s contents, methodology and resources, however they were divided about its duration. The Web as a tool in distance education was approved by the students. If it was not for the Web they could not have taken part in a continuing education program. All students said they would attend another virtual course, if available. Even though most of them did not have difficulty adapting to the virtual environment, they did feel that an adaptation period would be of value. CONCLUSIONS: A Web-based course may be more effective than other distance education methodologies because it is more interactive and dynamic. On-line material can be constantly reviewed and updated, and the students can have the opportunity to submit commentaries or questions directly to the teaching staff. A Web-based course also allows the students to go beyond the course content as they learn how to search and take advantage of the huge resources of information available on the Internet.

Adult↗

PubMed2004

A sense of presence and self-reported performance in international teams.

Research over the last two decades has explored the relationship between a variety of states of consciousness, performance, and motivation. These have included flow and a sense of presence in face-to-face, online, and virtual environments. This study examined the relationship between presence and flow experienced by 75 male and female participants from several Pacific Rim nations on 4 international teams and their self-reported performance, enjoyment, and motivation associated with team-related tasks. The results indicate that in these task situations, which are relatively novel because of their cultural diversity, self-reported performance correlated more highly with presence (r=.34, df=72, p<.01) than flow (r=.26, df=71, p<.05). Enjoyment and motivation, however, correlated more highly with flow (r =.60, df=71, p<.01 and r=.40, df=71, p<.01, respectively) than presence (r=.26, p<.05 and r=.25, p<.05). These findings suggest the need to explore further the relationship between activity- or task-related states of consciousness, the characteristics of the tasks involved, particularly in terms of their novelty, and the effect on performance and motivation.

Achievement↗

PubMed2004

Haptic identification of common objects: effects of constraining the manual exploration process.

In this article, we address the effects on haptic recognition of common objects when manual exploration is constrained by using two kinds of rigid links--sheaths (Experiment 1A) and probes (Experiments 1B and 2). The collective effects of five different constraints are considered, including three from previous research (i.e., reducing the number of end effectors, wearing a compliant finger cover, and splinting the fingers; Klatzky, Loomis, Lederman, Wake, & Fujita, 1993) and from two current constraints (i.e., wearing a rigid finger sheath and using a rigid probe). The resulting impairments are interpreted in terms of the loss of somatosensory information from cutaneous and/or kinesthetic inputs. In addition, we relate the results to the design of haptic interfaces for teleoperation and virtual environments, which share some of the same reduction of sensory cues that we have produced experimentally.

Fingers↗