Is It a Cube? Common Visual Perception of Cuboid Drawings

A cube is one of the most fundamental shapes we can draw and can observe from a drawing. The two visualization methods most commonly applied in mathematics textbooks and education are the axonometric and the perspective representations. However, what we see in the drawing is really a cube or only a general cuboid (i.e., a polyhedron with different edge lengths). In this experimental study, 153 first-year ( 19–20-year-old) students, two-thirds of them being female, were asked to interactively adjust a cuboid figure until they believe what they see is really a cube. We were interested in how coherently people, who are actually students of arts studies and engineering with advanced spatial perception skills in most cases, evaluate these drawings. What we have experienced is that for most people there is a common visual understanding of seeing a cube (and not a general cuboid). Moreover, this common sense is surprisingly close to the conventions applied in axonometric drawings, and to the theoretical, geometric solution in the case of three-point perspective drawings, which is the most realistic visualization method.

Is a Preference for Realism Really Naive After All? A Cognitive Model of Learning with Realistic Visualizations

The use of realistic visualizations has gained considerable interest due to the proliferation of virtual reality equipment. This review is concerned with the theoretical basis, technical implementation, cognitive effects, and educational implications of using realistic visualizations. Realism can be useful for learners, but in several studies, more abstract illustrations have resulted in higher performance. Furthermore, a preference for realistic visualization has been declared as being based on misconceptions regarding the cognitive system. However, we argue that this perspective is unable to fully explain the conflicting results found in the literature. To fill this theoretical gap, we devised a model to describe and compare the various levels of realism found in visualizations. We define realism as a combination of three dimensions: geometry, shading, and rendering. By varying these dimensions, it is possible to create a variety of realistic graphics. Thus, when comparing different visualizations, the realism of each of these three dimensions needs to be considered individually. Based on this technical definition, we introduce a cognitive model of learning with realistic visualizations that includes three different stages: perception, schema construction, and testing. At these three stages, variables such as the perceptual load generated by the visualization, learner characteristics influencing how well details are processed, and test types that demand concrete or flexible representations can affect whether realism fosters or hinders learning. Using the cognitive model presented in this paper, more accurate predictions and recommendations concerning the use of realism can be formulated.

Which emphasis technique to use? Perception of emphasis techniques with varying distractors, backgrounds, and visualization types

Emphasis effects are visual changes that make data elements distinct from their surroundings. Designers may use computational saliency models to predict how a viewer’s attention will be guided by a specific effect; however, although saliency models provide a foundational understanding of emphasis perception, they only cover specific visual effects in abstract conditions. To address these limitations, we carried out crowdsourced studies that evaluate emphasis perception in a wider range of conditions than previously studied. We varied effect magnitude, distractor number and type, background, and visualization type, and measured the perceived emphasis of 12 visual effects. Our results show that there are perceptual commonalities of emphasis across a wide range of environments, but also that there are limitations on perceptibility for some effects, dependent on a visualization’s background or type. We developed a model of emphasis predictability based on simple scatterplots that can be extended to other viewing conditions. Our studies provide designers with new understanding of how viewers experience emphasis in realistic visualization settings.

Three-dimensional echocardiography

Despite the fact that three-dimensional echocardiography (3DE) has been available for many years, its utilization on a routine clinical basis has been rather limited. However, recent improvements in image quality, semi-automated quantification, better workflow, and other developments such as fusion imaging, have now accelerated the integration of 3D imaging into routine echo practice. In this chapter, we have reviewed the standard and well established applications of the technique such as volumetric chamber analysis and 3D evaluation of valvular pathology, as well as highlighting some of the exciting new developments such as the use of artificial intelligence and photo-realistic visualization. these newer techniques will undoubtedly help ensure that 3D echocardiography plays a pivotal role in contemporary cardiac imaging leading and cutting edge patient care.

3D Technologies to Acquire and Visualize the Human Body for Improving Dietetic Treatment

This research aims to improve adherence to dietetic-nutritional treatment using state-of-the-art RGB-D sensor and virtual reality (VR) technology. Recent studies show that adherence to treatment can be improved by using multimedia technologies which impact on the body awareness of patients. However, there are no studies published to date using 3D data and VR technologies for this purpose. This paper describes a system capable of obtaining the complete 3D model of a body with high accuracy and a realistic visualization for 2D and VR devices to be used for studying the effect of 3D technologies on adherence to obesity treatment.

The Impact of Visualization Format and Navigational Options on Laypeople’s Perception and Preference of Surgery Information Videos: Randomized Controlled Trial and Online Survey (Preprint)

BACKGROUND Patients need to be educated about possible treatment choices in order to make informed medical decisions. As most patients are medical laypeople, they find it difficult to understand complex medical information sufficiently to feel confident about a decision. Multimedia interventions such as videos are increasingly used to supplement personal consultations with medical professionals. Former research has shown that such interventions may have a positive effect on understanding, decision making, and emotional reactions. However, it is thus far unclear how different features of videos influence these outcomes. OBJECTIVE We aimed to examine the impact of visualization formats and basic navigational options in medical information videos about cruciate ligament surgery on recipients’ knowledge gain, emotions, attitude, and hypothetical decision-making ability. METHODS In a between-group randomized experiment (Study 1), 151 participants watched 1 of 4 videos (schematic vs realistic visualization; available vs unavailable navigational options). In a separate online survey (Study 2), 110 participants indicated their preference for a video design. All participants were medical laypeople without personal experience with a cruciate ligament rupture and were presented with a fictional decision situation. RESULTS In Study 1, participants who used navigational options (n=36) gained significantly more factual knowledge (P=.005) and procedural knowledge (P<.001) than participants who did not have or use navigational options (n=115). A realistic visualization induced more fear (P=.001) and disgust (P<.001) than a schematic video. Attitude toward the surgery (P=.02) and certainty regarding the decision for or against surgery (P<.001) were significantly more positive after watching the video than before watching the video. Participants who watched a schematic video rated the video significantly higher than that by participants who watched a realistic video (P<.001). There were no significant group differences with regard to hypothetical decision making and attitude toward the intervention. In addition, we did not identify any influence of the visualization format on knowledge acquisition. In Study 2, 58 of 110 participants (52.7%) indicated that they would prefer a schematic visualization, 26 (23.6%) preferred a realistic visualization, 17 (15.5%) wanted either visualization, and 9 (8.2%) did not want to watch a video at all. Of the participants who wanted to watch a video, 91 (90.1%) preferred to have navigational options, 3 (3.0%) preferred not to have navigational options, and 7 (6.9%) did not mind the options. CONCLUSION Our study indicates that the perception of medical information videos is influenced by their design. Schematic videos with navigational options are the most helpful among all videos to avoid negative emotions and support knowledge acquisition when informing patients about an intervention. The visualization format and navigational options are important features that should be considered when designing medical videos for patient education. CLINICALTRIAL Deutsches Register Klinischer Studien DRKS00016003; https://www.drks.de/drks_web/ navigate.do?navigationId= trial.HTML&TRIAL_ID=DRKS00016003 (Archived by WebCite at http://www.webcitation.org/746ASSAhN)