Emotions are associated with the genesis of visually induced motion sickness in virtual reality.

Visually induced motion sickness (VIMS) is a well-known side effect of virtual reality (VR) immersion, with symptoms including nausea, disorientation, and oculomotor discomfort. Previous studies have shown that pleasant music, odor, and taste can mitigate VIMS symptomatology, but the mechanism by which this occurs remains unclear. We predicted that positive emotions influence the VIMS-reducing effects. To investigate this, we conducted an experimental study with 68 subjects divided into two groups. The groups were exposed to either positive or neutral emotions before and during the VIMS-provoking stimulus. Otherwise, they performed exactly the same task of estimating the time-to-contact while confronted with a VIMS-provoking moving starfield stimulation. Emotions were induced by means of pre-tested videos and with International Affective Picture System (IAPS) images embedded in the starfield simulation. We monitored emotion induction before, during, and after the simulation, using the Self-Assessment Manikin (SAM) valence and arousal scales. VIMS was assessed before and after exposure using the Simulator Sickness Questionnaire (SSQ) and during simulation using the Fast Motion Sickness Scale (FMS) and FMS-D for dizziness symptoms. VIMS symptomatology did not differ between groups, but valence and arousal were correlated with perceived VIMS symptoms. For instance, reported positive valence prior to VR exposure was found to be related to milder VIMS symptoms and, conversely, experienced symptoms during simulation were negatively related to subjects' valence. This study sheds light on the complex and potentially bidirectional relationship of VIMS and emotions and provides starting points for further research on the use of positive emotions to prevent VIMS.

Outcome in patients with left common pulmonary vein after cryoablation with second-generation cryoballoon.

BACKGROUND: Pulmonary vein isolation (PVI) has become a widely accepted therapy in patients suffering from symptomatic atrial fibrillation (AF). HYPOTHESIS: AF-free survival differs in patients with left common pulmonary vein (LCPV) after PVI with second-generation cryoballoon. METHODS: We included patients scheduled for first PVI for paroxysmal or persistent AF. Symptomatic and/or documented arrhythmia episodes (>30 seconds) were defined as AF recurrence, excluding a 3-month blanking period. RESULTS: We observed a LCPV in 37 of 270 consecutive patients (13.7%). Analyses were performed in a 1:1 propensity score matched cohort of 68 patients. During a median follow-up of 77.0 weeks, 37 patients (54.4%) had recurrent AF. The prevalence of LCPV was numerically higher in patients with AF recurrence (62.2% vs 35.5%, P  =  0.051) and Kaplan-Meier analysis showed lower AF-free survival in patients with existence of a LCPV (P  =  0.028). At 1-year follow-up, 70.6% of patients without versus 55.1% of patients with LCPV were free of AF. Multivariate Cox regression analysis revealed presence of a LCPV (hazard ratio [HR]: 2.996), chronic heart failure (HR: 3.423), and mitral regurgitation > I° (HR: 2.571) as predictors of AF recurrence. CONCLUSION: Patients with LCPV had significantly reduced AF-free survival after ablation with the second-generation cryoballoon, despite similar acutely successful PVIs.

A Systematic Literature Review of Virtual Reality Locomotion Taxonomies.

The change of the user's viewpoint in an immersive virtual environment, called locomotion, is one of the key components in a virtual reality interface. Effects of locomotion, such as simulator sickness or disorientation, depend on the specific design of the locomotion method and can influence the task performance as well as the overall acceptance of the virtual reality system. Thus, it is important that a locomotion method achieves the intended effects. The complexity of this task has increased with the growing number of locomotion methods and design choices in recent years. Locomotion taxonomies are classification schemes that group multiple locomotion methods and can aid in the design and selection of locomotion methods. Like locomotion methods themselves, there exist multiple locomotion taxonomies, each with a different focus and, consequently, a different possible outcome. However, there is little research that focuses on locomotion taxonomies. We performed a systematic literature review to provide an overview of possible locomotion taxonomies and analysis of possible decision criteria such as impact, common elements, and use cases for locomotion taxonomies. We aim to support future research on the design, choice, and evaluation of locomotion taxonomies and thereby support future research on virtual reality locomotion.