# HMD-Based VR Tool for Traffic Psychological Examination: Conceptualization and Design Proposition
## 1 Introduction
### Potential of VR Technologies for TPE  
VR technologies, following the development of computer graphics and increased computational power have only recently become common. VR can efficiently generate immersive virtual worlds within user interfaces involving human-centered interactivity and sensory feedback [14]. The significant potential of VR simulations was anticipated long before VR technologies were available to the general public and was increasingly and successfully applied in many expert areas such as laparoscopic surgery [15], industry and maintenance [16], geoinformatics [17] and other fields. Driving simulation and VR technologies are closely related from their very beginning in the 1960s [14], including especially computer-generated imagery (CGI) and physical and mental immersion into VR content. From the 1960s onwards, virtual environments have grown to become a promising trend for various simulations since they offer safe and economic opportunities to reliably explore situations happening in the real world [18]. Generally, virtual simulations help psychologists and researchers collect valid data on human behavior, sensorimotor activity and cognitive processes, because simulations provide a reality-like environment where cognitive phenomena are considered equivalent to reality and can be directly transferable to practice [19]. For more than 50 years, high-fidelity driving simulators were designed to help professions such as pilots or drivers assess and train their necessary skills. However, traditional big simulators possess several practical and conceptual limitations, which have not been successfully resolved. The most problematic for TPE is the immobility of simulators, cost-inefficiency, inconsistent visualization and fidelity aspects [20; 21], space requirements, HW and SW technical limitations (e.g., licensing and support) and the necessity of continuous technical maintenance. Conceptually, regarding their specific setting and form, simulators lose much of their ability to generate a sense of immersion and presence compared to reality [2]. The subjective immersion may refer to a perceived level of danger affecting for example sleepiness or other phenomena [22; 23], which are highly relevant for driving activity. The research on driving simulators generally provided supportive evidence for validity of driving simulators [24; 25], but the relatively small number of participants in these studies and obsolescence of the technologies used speak for the necessity of further empirical tests. The abovementioned limitations prevented driving simulators from spreading into widespread diagnostic practice and driving skill assessment remained complemented by the standard TPE. From several relevant perspectives the use of HMD-based VR technologies for driving skill assessment can be seen as the best path towards widespread practice of using simulations for this very purpose. VR-based assessment platforms allow psychologists to design critical scenarios in which the driving skill may be demonstrated. It also concurrently offers strict experimental control as well as a wide range of additional measures including physiology and sensorimotor activity of the driver, which may indicate features of a driver undetectable by means of traditional examination methods. It represents the leap from the abstract laboratory examination into dynamic and complex simulations, where users are perceptually surrounded by a virtual world preserving a high level of ecological validity, while maintaining experimental control. The extent to which the simulator engages potential users regarding the quality and principles of cognitive activities as they happen in the real-world task, is labeled as cognitive fidelity [26]. Head-mounted virtual displays with their function of isolating users from their physical reality [27], while securing an adequate level of visual and cognitive fidelity [28], generate psychological manifestations that can be classified as immersion into the virtual world [29; 30].