Positive Technology Journal

Kino 3D is a forum (in Italian) about open-source computer graphics. It includes several sections:

- Discussion on 2D and 3D computer graphics and open source for any platform;

- OpenLab: Experiments, work in progress, prototypes;

- Tutorial about Blender (the open source, cross platform suite of tools for 3D creation);

- Discussion about video, animations, and 2D/3D videogames;

- Off topics;

- A link to the international Blender forum;

The forum is an useul resource for professionals and people interested in knowing more about the world of open-source computer graphics.

The 4th Congress on Applications of Virtual Reality (CARVI 2006) will be held on 15-16 June in Vitoria-Gasteiz (Spain) and organized by EUVE Technological Center specialised in Virtual Reality, Television, Virtual Engineering and Meteorology. The Conference is aimed at architecture, urban planning, reconstruction of cultural heritage, civil works, engineering, television, advertising, institutions.

Visit the conference web site for more information

The value of virtual reality-simulator training in the development of laparoscopic surgical skills.

J Minim Invasive Gynecol. 2006 Apr;13(2):126-133

Authors: Hart R, Doherty DA, Karthigasu K, Garry R

OBJECTIVE: To determine the effectiveness of virtual reality (VR) training in improving the surgical skills of medical students and gynecologic trainees. DESIGN: A prospective observational study to assess the changes observed in objectively measured surgical performance after VR training. SETTING AND POPULATION: University teaching hospital and the laboratories of the University of Western Australia. PARTICIPANTS: Fifteen 5th-year medical students, six junior-doctor trainees (years 1-3), and eight senior trainees (years 4-6). INTERVENTIONS: Standard gynecologic procedures before and after VR training were undertaken on sheep. The procedures were video-recorded and edited to blind the scorer as to identity and seniority of the operator. The procedures were scored using a combination of operative time and penalties for surgical errors. The surgical scores were correlated with the VR scores. MEASUREMENTS AND MAIN RESULTS: Operative skills were assessed using a combination score compiled from scores obtained while undertaking salpingectomy, salpingotomy, and tubal clipping. Virtual reality scores were also a combination score derived from summation of various computer-calculated measures of time and accuracy in undertaking two standardized exercises. RESULTS: The baseline VR scores were significantly related to the overall pre-training scores (salpingectomy p = .032). A better initial VR score was also predictive of better surgical performance. The initial VR score was also predictive of improvement observed between baseline and post-training (p = .004). CONCLUSION: Virtual reality training is of value in improving surgical skills in the clinical environment. It appears to be of most value in the earliest stages of training. These data suggest that serious consideration should be given to incorporating VR training into the training program of obstetricians and gynecologists at an early stage.

Humans Ignore Motion and Stereo Cues in Favor of a Fictional Stable World.

Curr Biol. 2006 Feb 21;16(4):428-432

Authors: Glennerster A, Tcheang L, Gilson SJ, Fitzgibbon AW, Parker AJ

As we move through the world, our eyes acquire a sequence of images. The information from this sequence is sufficient to determine the structure of a three-dimensional scene, up to a scale factor determined by the distance that the eyes have moved . Previous evidence shows that the human visual system accounts for the distance the observer has walked and the separation of the eyes when judging the scale, shape, and distance of objects. However, in an immersive virtual-reality environment, observers failed to notice when a scene expanded or contracted, despite having consistent information about scale from both distance walked and binocular vision. This failure led to large errors in judging the size of objects. The pattern of errors cannot be explained by assuming a visual reconstruction of the scene with an incorrect estimate of interocular separation or distance walked. Instead, it is consistent with a Bayesian model of cue integration in which the efficacy of motion and disparity cues is greater at near viewing distances. Our results imply that observers are more willing to adjust their estimate of interocular separation or distance walked than to accept that the scene has changed in size.

Intelligent inferencing and haptic simulation for Chinese acupuncture learning and training.

IEEE Trans Inf Technol Biomed. 2006 Jan;10(1):28-41

Authors: Heng PA, Wong TT, Yang R, Chui YP, Xie YM, Leung KS, Leung PC

This paper presents an intelligent virtual environment for Chinese acupuncture learning and training using state-of-the-art virtual reality technology. It is the first step toward developing a comprehensive virtual human model for studying Chinese medicine. Students can learn and practice acupuncture in the proposed 3-D interactive virtual environment that supports a force feedback interface for needle insertion. Thus, students not only "see" but also "touch" the virtual patient. With high performance computers, highly informative and flexible visualization of acupuncture points of various related meridian and collateral can be highlighted to guide the students during training. A computer-based expert system using our newly proposed intelligent fuzzy petri net is designed and implemented to train the students to treat different diseases using acupuncture. Such an intelligent virtual reality system can provide an interesting and effective learning environment for Chinese acupuncture.

Visual and nonvisual contributions to three-dimensional heading selectivity in the medial superior temporal area.

J Neurosci. 2006 Jan 4;26(1):73-85

Authors: Gu Y, Watkins PV, Angelaki DE, DeAngelis GC

Robust perception of self-motion requires integration of visual motion signals with nonvisual cues. Neurons in the dorsal subdivision of the medial superior temporal area (MSTd) may be involved in this sensory integration, because they respond selectively to global patterns of optic flow, as well as translational motion in darkness. Using a virtual-reality system, we have characterized the three-dimensional (3D) tuning of MSTd neurons to heading directions defined by optic flow alone, inertial motion alone, and congruent combinations of the two cues. Among 255 MSTd neurons, 98% exhibited significant 3D heading tuning in response to optic flow, whereas 64% were selective for heading defined by inertial motion. Heading preferences for visual and inertial motion could be aligned but were just as frequently opposite. Moreover, heading selectivity in response to congruent visual/vestibular stimulation was typically weaker than that obtained using optic flow alone, and heading preferences under congruent stimulation were dominated by the visual input. Thus, MSTd neurons generally did not integrate visual and nonvisual cues to achieve better heading selectivity. A simple two-layer neural network, which received eye-centered visual inputs and head-centered vestibular inputs, reproduced the major features of the MSTd data. The network was trained to compute heading in a head-centered reference frame under all stimulus conditions, such that it performed a selective reference-frame transformation of visual, but not vestibular, signals. The similarity between network hidden units and MSTd neurons suggests that MSTd may be an early stage of sensory convergence involved in transforming optic flow information into a (head-centered) reference frame that facilitates integration with vestibular signals.

Simulated driving and brain imaging: combining behavior, brain activity, and virtual reality

CNS Spectr. 2006 Jan;11(1):52-62

Authors: Carvalho KN, Pearlson GD, Astur RS, Calhoun VD

Introduction: Virtual reality in the form of simulated driving is a useful tool for studying the brain. Various clinical questions can be addressed, including both the role of alcohol as a modulator of brain function and regional brain activation related to elements of driving. Objective: We reviewed a study of the neural correlates of alcohol intoxication through the use of a simulated-driving paradigm and wished to demonstrate the utility of recording continuous-driving behavior through a new study using a programmable driving simulator developed at our center. Methods: Functional magnetic resonance imaging data was collected from subjects while operating a driving simulator. Independent component analysis (ICA) was used to analyze the data. Specific brain regions modulated by alcohol, and relationships between behavior, brain function, and alcohol blood levels were examined with aggregate behavioral measures. Fifteen driving epochs taken from two subjects while also recording continuously recorded driving variables were analyzed with ICA. Results: Preliminary findings reveal that four independent components correlate with various aspects of behavior. An increase in braking while driving was found to increase activation in motor areas, while cerebellar areas showed signal increases during steering maintenance, yet signal decreases during steering changes. Additional components and significant findings are further outlined. Conclusion: In summary, continuous behavioral variables conjoined with ICA may offer new insight into the neural correlates of complex human behavior.

Behav Brain Sci. 2005 Dec;28(6):773

Authors: Smythies JR

This commentary reviews and extends the target article's treatment of the topic of the role of acetylcholine in hallucinatory experience in health and disease. Particular attention is paid to differentiating muscarinic and nicotinic effects in modulating the use of virtual reality mechanisms by the brain. Then, attention is drawn to the similarities between these aspects of brain function and certain aspects of television digital compression technology.

Authors: Morris JP, Pelphrey KA, McCarthy G

Abstract. We investigated the necessity of biological motion for activation of the posterior superior temporal sulcus (pSTS) in circumstances in which the rapid approach of the observer to a virtual human induced the observer to make inferences about the characters intentions. Using a virtual reality environment, subjects experienced themselves walking towards a complex scene composed of animate and/or inanimate objects. During "person" trials, the scene contained a virtual human either making a simple gesture such as scratching his face (Study 1) or standing completely still (Study 2). During "object" trials, the scenes contained items such as furniture, a face portrait, and a clock, but not the virtual human. Using functional MRI to measure brain activity, we demonstrated strong activity in the pSTS while the observer approached the social scene, but only when the virtual human was making gestures. This result emphasizes the importance of biological motion in inferring the intentions of others.

Ergonomics. 2005 Aug;48(10):1223-42

Authors: Hsiao H, Simeonov P, Dotson B, Ammons D, Kau TY, Chiou S

This study investigated the effect of adding real planks, in virtual scaffolding models of elevation, on human performance in a surround-screen virtual reality (SSVR) system. Twenty-four construction workers and 24 inexperienced controls performed walking tasks on real and virtual planks at three virtual heights (0, 6 m, 12 m) and two scaffolding-platform-width conditions (30, 60 cm). Gait patterns, walking instability measurements and cardiovascular reactivity were assessed. The results showed differences in human responses to real vs. virtual planks in walking patterns, instability score and heart-rate inter-beat intervals; it appeared that adding real planks in the SSVR virtual scaffolding model enhanced the quality of SSVR as a human - environment interface research tool. In addition, there were significant differences in performance between construction workers and the control group. The inexperienced participants were more unstable as compared to construction workers. Both groups increased their stride length with repetitions of the task, indicating a possibly confidence- or habit-related learning effect. The practical implications of this study are in the adoption of augmented virtual models of elevated construction environments for injury prevention research, and the development of programme for balance-control training to reduce the risk of falls at elevation before workers enter a construction job.