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Jun 23, 2010

First person experience of body transfer in virtual reality

First person experience of body transfer in virtual reality.

PLoS One. 2010;5(5):e10564

Authors: Slater M, Spanlang B, Sanchez-Vives MV, Blanke O

BACKGROUND: Altering the normal association between touch and its visual correlate can result in the illusory perception of a fake limb as part of our own body. Thus, when touch is seen to be applied to a rubber hand while felt synchronously on the corresponding hidden real hand, an illusion of ownership of the rubber hand usually occurs. The illusion has also been demonstrated using visuomotor correlation between the movements of the hidden real hand and the seen fake hand. This type of paradigm has been used with respect to the whole body generating out-of-the-body and body substitution illusions. However, such studies have only ever manipulated a single factor and although they used a form of virtual reality have not exploited the power of immersive virtual reality (IVR) to produce radical transformations in body ownership. PRINCIPAL FINDINGS: Here we show that a first person perspective of a life-sized virtual human female body that appears to substitute the male subjects' own bodies was sufficient to generate a body transfer illusion. This was demonstrated subjectively by questionnaire and physiologically through heart-rate deceleration in response to a threat to the virtual body. This finding is in contrast to earlier experimental studies that assume visuotactile synchrony to be the critical contributory factor in ownership illusions. Our finding was possible because IVR allowed us to use a novel experimental design for this type of problem with three independent binary factors: (i) perspective position (first or third), (ii) synchronous or asynchronous mirror reflections and (iii) synchrony or asynchrony between felt and seen touch. CONCLUSIONS: The results support the notion that bottom-up perceptual mechanisms can temporarily override top down knowledge resulting in a radical illusion of transfer of body ownership. The research also illustrates immersive virtual reality as a powerful tool in the study of body representation and experience, since it supports experimental manipulations that would otherwise be infeasible, with the technology being mature enough to represent human bodies and their motion.

Jan 09, 2010

Sense of agency primes manual motor responses

Sense of agency primes manual motor responses.

Perception. 2009;38(1):69-78

Authors: Longo MR, Haggard P

Perceiving the body influences how we perceive and respond to stimuli in the world. We investigated the respective effects of different components of bodily representation--the senses of ownership and agency--on responses to simple visual stimuli. Participants viewed a video image of their hand on a computer monitor presented either in real time, or with a systematic delay. Blocks began with an induction period in which the index finger was (i) brushed, (ii) passively moved, or (iii) actively moved by the participant. Subjective reports showed that the sense of ownership over the seen hand emerged with synchronous video, regardless of the type of induction, whereas the sense of agency over the hand emerged only following synchronous video with active movement. Following induction, participants responded as quickly as possible to the onset of visual stimuli near the hand by pressing a button with their other hand. Reaction time was significantly speeded when participants had a sense of agency over their seen hand. This effect was eliminated when participants responded vocally, suggesting that it reflects priming of manual responses, rather than enhanced stimulus detection. These results suggest that vision of one's own hand-and, specifically, the sense of agency over that hand-primes manual motor responses.

Dec 08, 2009

Allosphere: University of California, Santa Barbara

The AlloSphere is a spherical space in which immersive, virtual environments allow researchers to convert large data sets into experiences of sight and sound. For example, it allows researchers to “fly” through a hydrogen atom while hearing sonified features of the wavefunction of its single electron to help describe invisible processes of nature.

The facility consists of a 30-foot diameter sphere built inside a 3-story cube that’s nearly echo-free. Inside the chamber are two spherical hemispheres that are constructed of perforated aluminum designed to be optically opaque and acoustically transparent. A 7-foot-wide bridge runs across the center, supporting the users. High-resolution video projectors can project images across the entire inner surface enabling seamless stereo-optic 3D projection.

Impact of the virtual reality on the neural representation of an environment

Impact of the virtual reality on the neural representation of an environment.

Hum Brain Mapp. 2009 Dec 4;

Authors: Mellet E, Laou L, Petit L, Zago L, Mazoyer B, Tzourio-Mazoyer N

Despite the increasing use of virtual reality, the impact on cerebral representation of topographical knowledge of learning by virtual reality rather than by actual locomotion has never been investigated. To tackle this challenging issue, we conducted an experiment wherein participants learned an immersive virtual environment using a joystick. The following day, participants' brain activity was monitored by functional magnetic resonance imaging while they mentally estimated distances in this environment. Results were compared with that of participants performing the same task but having learned the real version of the environment by actual walking. We detected a large set of areas shared by both groups including the parieto-frontal areas and the parahippocampal gyrus. More importantly, although participants of both groups performed the same mental task and exhibited similar behavioral performances, they differed at the brain activity level. Unlike real learners, virtual learners activated a left-lateralized network associated with tool manipulation and action semantics. This demonstrated that a neural fingerprint distinguishing virtual from real learning persists when subjects use a mental representation of the learnt environment with equivalent performances. Hum Brain Mapp, 2010. (c) 2009 Wiley-Liss, Inc.

Dec 06, 2009

Avatar: Can't wait any longer

I just can not wait for the new James Cameron's movie Avatar...

Nov 18, 2009

RAVE 2010 - Real Actions in Virtual Environments - Call for Papers

RAVE 2010 - Real Actions in Virtual Environments - Call for Papers

See website: http://www.raveconference.com

* When: 3rd March, 2010.

* Where:

Palau de les Heures, University of Barcelona, Campus Mundet, Passeig de la Vall d’Hebron, 171 08035 Barcelona.

* Keynote Speaker - Dr Hunter Hoffman,

http://www.hitl.washington.edu/people/hunter/, University of Washington, USA

* Papers -  may be submitted directly for oral presentation at the conference and a special issue of PRESENCE: Teleoperators and Virtual Environments, MIT Press, to be published in August 2010.

* Abstracts may be submitted for oral presentation at the conference or will presented as posters (see website for details).

***Deadline for paper submission: 8th January, 2010*** 23.59 Central European Time (Paris, Madrid)

Oct 20, 2009

Inducing a virtual hand ownership illusion through a brain-computer interface

Inducing a virtual hand ownership illusion through a brain-computer interface.

Neuroreport. 2009 Apr 22;20(6):589-594

Authors: Perez-Marcos D, Slater M, Sanchez-Vives MV

The apparently stable brain representation of our bodies is easily challenged. We have recently shown that the illusion of ownership of a three-dimensional virtual hand can be evoked through synchronous tactile stimulation of a person's hidden real hand and that of the virtual hand. This reproduces the well-known rubber-hand illusion, but in virtual reality. Here we show that some aspects of the illusion can also occur through motor imagery used to control movements of a virtual hand. When movements of the virtual hand followed motor imagery, the illusion of ownership of the virtual hand was evoked and muscle activity measured through electromyogram correlated with movements of the virtual arm. Using virtual bodies has a great potential in the fields of physical and neural rehabilitation, making the understanding of ownership of a virtual body highly relevant.

Sep 21, 2009

Driving dreams: cortical activations during imagined passive and active whole body movemen

Driving dreams: cortical activations during imagined passive and active whole body movement.

Ann N Y Acad Sci. 2009 May;1164:372-5

Authors: Flanagin VL, Wutte M, Glasauer S, Jahn K

It is unclear how subjects perceive and process self-motion cues in virtual reality environments. Movement could be perceived as passive, akin to riding in a car, or active, such as walking down the street. These two very different types of self-motion were studied here using motor imagery in fMRI. In addition, the relative importance of visual and proprioceptive training cues was examined. Stronger activations were found during proprioceptive motor imagery compared with visual motor imagery, suggesting that proprioceptive signals are important for successful imagined movement. No significant activations were found during active movement with proprioceptive training. Passive locomotion, however, was correlated with activity in an occipital-parietal and parahippocampal cortical network, which are the same regions found during navigation with virtual reality stimuli.

Reactivity to cannabis cues in virtual reality environments

Reactivity to cannabis cues in virtual reality environments.

J Psychoactive Drugs. 2009 Jun;41(2):105-12

Authors: Bordnick PS, Copp HL, Traylor A, Graap KM, Carter BL, Walton A, Ferrer M

Virtual reality (VR) cue environments have been developed and successfully tested in nicotine, cocaine, and alcohol abusers. Aims in the current article include the development and testing of a novel VR cannabis cue reactivity assessment system. It was hypothesized that subjective craving levels and attention to cannabis cues would be higher in VR environments with cannabis cues compared to VR neutral environments. Twenty nontreatment-seeking current cannabis smokers participated in the VR cue trial. During the VR cue trial, participants were exposed to four virtual environments that contained audio, visual, olfactory, and vibrotactile sensory stimuli. Two VR environments contained cannabis cues that consisted of a party room in which people were smoking cannabis and a room containing cannabis paraphernalia without people. Two VR neutral rooms without cannabis cues consisted of a digital art gallery with nature videos. Subjective craving and attention to cues were significantly higher in the VR cannabis environments compared to the VR neutral environments. These findings indicate that VR cannabis cue reactivity may offer a new technology-based method to advance addiction research and treatment.

The sensitivity of a virtual reality task to planning and prospective memory impairments

The sensitivity of a virtual reality task to planning and prospective memory impairments: Group differences and the efficacy of periodic alerts on performance.

Neuropsychol Rehabil. 2009 Aug 26;:1-25

Authors: Sweeney S, Kersel D, Morris RG, Manly T, Evans JJ

Executive functions have been argued to be the most vulnerable to brain injury. In providing an analogue of everyday situations amenable to control and management virtual reality (VR) may offer better insights into planning deficits consequent upon brain injury. Here 17 participants with a non-progressive brain injury and reported executive difficulties in everyday life were asked to perform a VR task (working in a furniture storage unit) that emphasised planning, rule following and prospective memory tasks. When compared with an age and IQ-matched control group, the patients were significantly poorer in terms of their strategy, their time-based prospective memory, the overall time required and their propensity to break rules. An examination of sensitivity and specificity of the VR task to group membership (brain-injured or control) showed that, with specificity set at maximum, sensitivity was only modest (at just over 50%). A second component to the study investigated whether the patients' performance could be improved by periodic auditory alerts. Previous studies have demonstrated that such cues can improve performance on laboratory tests, executive tests and everyday prospective memory tasks. Here, no significant changes in performance were detected. Potential reasons for this finding are discussed, including symptom severity and differences in the tasks employed in previous studies.

Increased personal space of patients with schizophrenia in a virtual social environment

Increased personal space of patients with schizophrenia in a virtual social environment.

Psychiatry Res. 2009 Sep 15;

Authors: Park SH, Ku J, Kim JJ, Jang HJ, Kim SY, Kim SH, Kim CH, Lee H, Kim IY, Kim SI

Virtual reality may be a good alternative method for measuring personal space and overcoming some limitations in previous studies on the social aspects of schizophrenia. Using this technology, we aimed to investigate the characteristics of personal space in patients with schizophrenia and evaluate the relationship between their social behaviors and schizophrenic symptoms. The distance from a virtual person and the angle of head orientation while talking to a virtual person in a virtual environment were measured in 30 patients with schizophrenia and 30 normal controls. It was found that patients with schizophrenia had longer distances and larger angles than did normal controls. The severity of the negative syndrome had significant inverse correlations with the distance from the angry and neutral virtual persons and with the angle of head orientation toward the happy and angry virtual persons, suggesting that negative symptoms may have a close relationship with personal space, including distancing and eye gaze. The larger personal space of patients may reflect their discomfort in close situations or cognitive deficits. Showing these profiles to patients could help them realize the amount of personal space they need.

The use of biofeedback in clinical virtual reality: the intrepid project

The use of biofeedback in clinical virtual reality: the intrepid project.

Stud Health Technol Inform. 2009;144:128-32

Authors: Repetto C, Gorini A, Algeri D, Vigna C, Gaggioli A, Riva G

In our protocol for the treatment of Generalized Anxiety Disorders we use Virtual reality (VR) to facilitate emotional regulation and the relaxation process. Using a biofeedback biomonitoring system (GSR, HR, Thermal) the patient is made aware of his or her reactions through the modification of some features of the VR environment in real time. Using mental exercises the patient learns to control these physiological parameters and using the feedback provided by the virtual environment is able to gauge his or her success. To test this concept, we planned a randomized controlled trial (NCT00602212), including three groups of 15 patients each (for a total of 45 patients): (1) the VR group, (2) the non-VR group, and (3) the waiting list (WL) group.

Jun 15, 2009

Equivalence of Real-World and Virtual-Reality Route Learning

Equivalence of Real-World and Virtual-Reality Route Learning: A Pilot Study.

Cyberpsychol Behav. 2009 Jun 10;

Authors: Lloyd J, Persaud NV, Powell TE

Abstract There is good evidence for effective transfer of learning from virtual to real-world environments, and this holds true even for complex spatial tasks such as route learning. However, there is little research into the simple equivalence of an individual's performance across real and virtual environments, an important topic which could support the use of virtual reality as an assessment and research tool. This pilot study compared route-learning performance in a desktop virtual town with performance around a real-world route. Participants were "driven" around a route through a virtual town and around a different (but equally complex) route through a real-world suburb, then asked to direct the driver back around each of the routes from memory. They completed strategy checklists after learning each route. Results indicated good equivalence between the real and virtual environments, with comparable error rates and no differences in strategy preferences. This demonstrates that simple desktop virtual environments may be a useful tool for assessment of and research into route learning.

Apr 29, 2009

Ultimate virtual reality will trigger five senses

Via New Scientist

The New Scientist reports that researchers at University of York and the University of Warwick are designing a device able to manipulate five of a person's senses, to provide them with the illusion of being somewhere else.

Mar 05, 2009

Virtual Cocoon: The ultimate VR device for psychotherapy

Scientists from the Universities of York and Warwick have developed the first Virtual Reality system that allows users to see, hear, smell taste and even touch. The prototype will be presented at Pioneers 09', an EPSRC showcase event to be held at London's Olympia Conference Centre on March 4

If the prototype can really do what it promises, it can have widespread applications in education, business, medical visualization and cybertherapy.

Credit: Image courtesy of Engineering and Physical Sciences Research Council



 

Jan 20, 2009

Spatial aspects of bodily self-consciousness

Spatial aspects of bodily self-consciousness.

Conscious Cogn. 2008 Dec 22;

Authors: Lenggenhager B, Mouthon M, Blanke O

Visual, somatosensory, and perspectival cues normally provide congruent information about where the self is experienced. Separating those cues by virtual reality techniques, recent studies found that self-location was systematically biased to where a visual-tactile event was seen. Here we developed a novel, repeatable and implicit measure of self-location to compare and extend previous protocols. We investigated illusory self-location and associated phenomenological aspects in a lying body position that facilitates clinically observed abnormal self-location (as on out-of-body experiences). The results confirm that the self is located to where touch is seen. This leads to either predictable lowering or elevation of self-localization, and the latter was accompanied by sensations of floating, as during out-of-body experiences. Using a novel measurement we show that the unitary and localized character of the self can be experimentally separated from both the origin of the visual perspective and the location of the seen body, which is compatible with clinical data.

Nov 03, 2008

Feeling present in arousing virtual reality worlds

Feeling present in arousing virtual reality worlds: prefrontal brain regions differentially orchestrate presence experience in adults and children.

Front Hum Neurosci. 2008;2:8

Authors: Baumgartner T, Speck D, Wettstein D, Masnari O, Beeli G, Jäncke L

Virtual reality (VR) is a powerful tool for simulating aspects of the real world. The success of VR is thought to depend on its ability to evoke a sense of "being there", that is, the feeling of "Presence". In view of the rapid progress in the development of increasingly more sophisticated virtual environments (VE), the importance of understanding the neural underpinnings of presence is growing. To date however, the neural correlates of this phenomenon have received very scant attention. An fMRI-based study with 52 adults and 25 children was therefore conducted using a highly immersive VE. The experience of presence in adult subjects was found to be modulated by two major strategies involving two homologous prefrontal brain structures. Whereas the right DLPFC controlled the sense of presence by down-regulating the activation in the egocentric dorsal visual processing stream, the left DLPFC up-regulated widespread areas of the medial prefrontal cortex known to be involved in self-reflective and stimulus-independent thoughts. In contrast, there was no evidence of these two strategies in children. In fact, anatomical analyses showed that these two prefrontal areas have not yet reached full maturity in children. Taken together, this study presents the first findings that show activation of a highly specific neural network orchestrating the experience of presence in adult subjects, and that the absence of activity in this neural network might contribute to the generally increased susceptibility of children for the experience of presence in VEs.

Sep 09, 2008

Modulating presence and impulsiveness by external stimulation of the brain

Modulating presence and impulsiveness by external stimulation of the brain

Behav Brain Funct. 2008 Aug 4;4(1):33

Authors: Beeli G, Casutt G, Baumgartner T, Jancke L

ABSTRACT: BACKGROUND: "The feeling of being there" is one possible way to describe the phenomenon of feeling present in a virtual environment and to act as if this environment is real. One brain area, which is hypothesized to be critically involved in modulating this feeling (also called presence) is the dorso-lateral prefrontal cortex (dlPFC), an area also associated with the control of impulsive behavior. METHODS: In our experiment we applied transcranial direct current stimulation (tDCS) to the right dlPFC in order to modulate the experience of presence while watching a virtual roller coaster ride. During the ride we also registered electro-dermal activity. Subjects also performed a test measuring impulsiveness and answered a questionnaire about their presence feeling while they were exposed to the virtual roller coaster scenario. RESULTS: Application of cathodal tDCS to the right dlPFC while subjects were exposed to a virtual roller coaster scenario modulates the electrodermal response to the virtual reality stimulus. In addition, measures reflecting impulsiveness were also modulated by application of cathodal tDCS to the right dlPFC. CONCLUSIONS: Modulating the activation with the right dlPFC results in substantial changes in responses of the vegetative nervous system and changed impulsiveness. The effects can be explained by theories discussing the top-down influence of the right dlPFC on the "impulsive system".

Mar 25, 2008

Physicality and Interaction: A Special Journal Issue of Interacting with Computers

Planned publication date: September 2008

Following the successful Physicality 2006 and Physicality 2007 International Workshops, which demonstrated the growing multi-disciplinary interest in this area of work, we invite submissions for this special issue on Physicality and Interaction for the interdisciplinary journal Interacting with Computers.

We live in an increasingly digital world yet our bodies and minds are naturally designed to interact with the physical. The products of the 21st century are and will be a synthesis of digital and physical elements embedded in new physical and social environments. As we design more hybrid physical/digital products, the distinctions for the user become blurred. It is therefore increasingly important that we understand what we gain, lose or confuse by the added digitality.

Augmented physical artefacts can be tailored and adapted to operate within a wide range of ecological settings. However, they also become more complex and require a fairly intensive design process to make them not simply practical and functional but also engaging. As a result, the need becomes even more pressing to comprehend the underlying computational intricacies, the physical form, properties and behaviour, the physical and social contexts, and the issues of aesthetics and creativity.

The issues in this field impact many areas of study: architecture, art, cognitive science, geography, human-computer interaction, philosophy, product design, sociology, tangible interface and ubiquitous computing.

We invite contributions that address physicality at various levels, including:

- design at the physical-digital frontier
- the philosophy of physicality
- artefact-focussed social interaction
- physically-inspired interaction in virtual worlds
- creativity and materiality
- interactive art and performance
- digital emulation of the physical
- the evolving role of digital artefacts in material culture

SUBMISSION DETAILS
Length guide: 4000 - 7000 words
Paper deadline: 1st April 2008

To expedite the reviewing process prospective authors are encouraged to send an abstract at their earliest convenience. Detailed author guidelines can be found here


Mar 20, 2008

2nd PEACH Summer School: Technologies and Applications - Dubrovnik, Croatia

Event Date: 9 July 2008 to 11 July 2008
Are you a presence researcher or PhD student? Are you looking to find out more about the latest presence research, technologies and applications? If so then the second PEACH Summer School is for you.

PEACH is an EU FP6 Coordination Action on Presence. Its objective is to stimulate, structure and support the presence research community, with a special focus on the challenges associated with the interdisciplinary character of the field. It also has the objective of producing visions and roadmaps to support ongoing and future research. The Summer School is the ideal place to join the leaders in the field for a series of lectures and presentations. There are also working groups, which will focus on the latest technologies and applications along with poster/demo sessions where you will present your work to other attendees and experts.

SPEAKERS INCLUDE
Prof Mel Slater, Universitat Politècnica de Catalunya (PRESENCCIA IP-EU Project)
Prof Franco Tecchia, PERCRO - Scuola Superiore Sant'Anna
Prof Mavi Sanchez-Vives, Institut d'Investigacions Biomèdiques August Pi i Sunyer (PRESENCCIA IP-EU Project)
Prof Selim Balcisoy, Sabanci University
Prof Benoit Macq, Université catholique de Louvain
Dr Xavier Marichal, Alterface S.A.
Dr Ralph Schroeder, Oxford Internet Institute
Dr Eric Meyer, Oxford Internet Institute
Prof Jeremy Bailenson, Stanford University
Prof Dominic Massaro, University of California, Santa Cruz
Prof Miriam Reiner, Technion (PRESENCCIA and IMMERSENCE IP-EU Project)
Fulvio Dominici, Ultramundum Foundation
Gianluca Zaffiro, Telecom Italia
Prof Igor Pandžić, University of Zagreb
Dr Marco Gillies, University College London
Dr Rod McCall, Fraunhofer FIT (IPCity EU Project)
Claudia Redaelli, ITIA
Prof. Martyn Bracewell, University of Wales, Bangor

The deadline for registration is the 18th April.