applied sciences Article Virtual Reality Exposure Therapy for Driving Phobia Disorder (2): System Refinement and Verification Amy Trappey 1,* , Charles V. Trappey 2 , Chia-Ming Chang 3, Meng-Chao Tsai 4, Routine R. T. Kuo 1 and Aislyn P. C. Lin 1 1 Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Hsinchu 300, Taiwan; [email protected] (R.R.T.K.); [email protected] (A.P.C.L.) 2 Department of Management Science, National Chiao Tung University, Hsinchu 300, Taiwan; [email protected] 3 Psychiatry Department, Chang Gung Memorial Hospital, Taipei 333, Taiwan; [email protected] 4 Department of Psychiatry, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan 330, Taiwan; [email protected] * Correspondence: [email protected]; Tel.: +886-3574-2651 Abstract: Driving phobia is a widespread anxiety disorder in modern society. Driving phobia dis- orders often cause difficulties in people’s professional and social activities. A growing trend for treating driving phobia is to apply virtual reality exposure therapy (VRET). We refined the system’s performance based on the previous research publication and have conducted a VRET pre-test research study with treatment and control group subjects to demonstrate the effectiveness of VRET. Some systemic problems were discovered in the first published experiment. For example, the experimental process and the virtual reality (VR) driving scenarios had to be modified to reflect realistic scenarios causing the fear of driving. These issues were identified and improvements made and verified in this research. A total of 130 subjects completed the driving behavior survey. Thirty subjects were randomly drawn from the subjects with high driving fear questionnaire scores and were invited to participate in the treatment experiments. The latest research presents the refined VRET for driving phobia disorders, Citation: Trappey, A.; Trappey, C.V.; including the revised system framework, the main modules and integration, and the subjects’ biodata Chang, C.-M.; Tsai, M.-C.; Kuo, R.R.T.; collection, management, and analysis. The experiment results provide strong evidence that the refined Lin, A.P.C. Virtual Reality Exposure VRET design helps subjects overcome driving phobias. The subjects’ subjective distress and fear of Therapy for Driving Phobia Disorder driving are reduced significantly through the implementation of VRET. (2): System Refinement and Verification. Appl. Sci. 2021, 11, 347. Keywords: driving phobia; post-traumatic stress disorder; virtual reality exposure therapy; physio- https://doi.org/10.3390/app11010347 logical signals Received: 8 December 2020 Accepted: 28 December 2020 Published: 31 December 2020 1. Introduction Publisher’s Note: MDPI stays neu- Severe motor vehicle crashes are one of the most frequent traumas experienced in the tral with regard to jurisdictional clai- United States (US) [1]. In 2018, the number of motor vehicle crashes exceeded 6.7 million in ms in published maps and institutio- the US and about 2.7 million people reported injuries in the traffic accidents [2]. According nal affiliations. to a National Institute of Mental Health (NIMH) study, about 39% of the motor vehicle accident (MVA) survivors met DSM-III-R criteria for post-traumatic stress disorder (PTSD). Patients with PTSD often experience disabling memories and anxiety related to the car accident event, and are likely to be subjectively distressed by environmental conditions Copyright: © 2020 by the authors. Li- with increased impairment in daily performance, such as commuting to work or driving a censee MDPI, Basel, Switzerland. car for pleasure [3]. The type of PTSD that is caused by MVAs is known as a driving phobia This article is an open access article disorder. Driving phobia is very common and the level of fear may range from mild to distributed under the terms and con- severe. Some patients are only afraid of specific driving conditions, while some cannot ditions of the Creative Commons At- bear to sit behind the steering wheel of a motor vehicle. tribution (CC BY) license (https:// creativecommons.org/licenses/by/ The adoption of VRET for PTSD treatments allows patients to be exposed to levels and 4.0/). scenarios of traumatic stimuli (or conditions) using sound, visual, and tactile immersions. Appl. Sci. 2021, 11, 347. https://doi.org/10.3390/app11010347 https://www.mdpi.com/journal/applsci Appl. Sci. 2021, 11, 347 2 of 16 The VRET approach follows the concept of systematic desensitization (SD), which is recog- nized in the field of clinical psychology for helping patients effectively overcome various phobia and anxiety disorders based on classical conditions. In some SD literature, VRET has been verified for being as effective as the traditional cognitive behavioral therapy (CBT) [4]. Using VRET, patients interact with near-real virtual representations of traumatic stimuli and scenarios to help the reduction of fears gradually and effectively. Several preliminary studies have supported the effectiveness of using VRET for driving phobia disorder [5–7], although these studies are largely case studies with qualitative perspectives. Nonetheless, the effects of VRET are confirmed to be significant when compared to traditional behavior therapy [8]. This research presents a new verification process to measure the effectiveness of VRET for driving phobia disorders. This refined VRET system, a newly modified and improved version based on our previous research, integrates the collection of the subjects’ biodata via a control group-based experimental design. The in-depth biodata analysis collected from the VRET experiments, combined with the treatment group vs. control group survey analysis, is presented as the objective evidence of the VRET effectiveness. The paper is organized in the following sections. In Section2, the literature review of VRET in the field of driving phobia treatment, self-measurement surveys related to driving behavior, and the patents related to VR driving applications are presented. Section3 depicts the methodologies and approaches applied and integrated in this research. Section4 presents the newly modified system architecture with the modules integrated to build the VRET platform for treating driving phobia disorders. Section5 presents the analyses of survey questionnaire results and subjects’ biodata during the VRET experiment. Statistical analyses, such as means and standard deviations of biodata and a one-way ANOVA are used to determine whether there are significant differences between biodata types (e.g., temperature, heart rate). Section6 summarizes the key findings and contributions of the research. The analytical results of VRET effectiveness for treating driving phobia and the future development required in the field are addressed in the final remarks. 2. Literature Review Driving is considered to be an essential skill for individuals living in modern society, a skill which facilitates the maintenance of independence, mobility, enables engagement in important activities, and is often a requirement of employment. People who suffered from the psychological impairment of serious motor vehicle accidents account for the majority of patients with driving phobia. Other possible reasons that lead to driving phobia include patients that suffer from claustrophobia may have panic attack while driving on the highway or in a traffic jams, patients that know someone that experienced a terrible car accident, or lack of trust in their own driving skills [9]. Based on the emotional processing theory [10], VRET can lead to fresh and neutral memory structures that, if applied to PTSD patients properly, can diminish old and traumatic memories, such as a bad car crash that often provokes and heightens anxiety. An increasing number of scholars have conducted research in the field of VRET with a focus on driving phobia. One early study used VRET in the treatment of PTSD symptoms in the aftermath of a serious motor vehicle accident. Six individuals reported either full or severe subsyndromal PTSD and completed ten sessions of VRET using software designed to create real-time driving scenarios. The results indicated significant reductions in post-trauma symptoms involving reexperiencing, avoidance, and emotional numbing, and VRET was successfully used in the treatment of PTSD following road accidents [5]. In one VRET plus cognitive behavioral therapy (CBT) for driving anxiety and aggression pilot study, six U.S. veterans who suffered from MVAs while serving in the military participated in the research. The study was a novel VRET + CBT for patients that integrated the anxiety and anger management components, although the sample size is very small (only six) [6]. Each veteran completed eight intervention sessions, as well as six to nine months follow-up assessments. At the end of the experiment, their hyperarousal in driving situations declined by 69%, aggressive driving declined by 29%, and risky driving declined by 21% [6]. In a pilot study adopting VRET [7], Appl. Sci. 2021, 11, 347 3 of 16 fourteen subjects with severe driving phobia disorders participated in psychotherapeutic, VRET, CBT sessions, and behavioral avoidance tests (BAT) when driving on the road. The treatment design placed the subjects under 10 days of therapeutic experiments. After the six to twelve weeks follow-up after experiments, thirteen out of fourteen patients maintained effective treatment results [7]. Although this was a pilot study, the experiment