Building resilience with the Stress Resilience Training System: Design validation and applications

Abstract

BACKGROUND: Resilience to stress is critical in today’s military service. Past work has shown that experts handle stress in more productive ways compared to novices. Training that specifically addresses stress regulation, such as the Graduated Stress Exposure paradigm, can build individual and unit resilience as well as adaptability so that stressors trigger effective stress coping skills rather than stress injury.

OBJECTIVE: We developed the Stress Resilience Training System (SRTS), a product of Perceptronics Solutions Inc., to demonstrate that a software training app can provide an effective individualized method for mitigating the negative effects of situational and mission-related stress, at the same time eliciting potentially positive effects on performance.

METHODS: Seven separate evaluations including a usability study, controlled experiments, and field evaluations have been conducted to date.

RESULTS: These studies have shown that the SRTS program effectively engages users to manage their stress, effectively reduces stress symptoms, and improves job performance.

CONCLUSIONS: The SRTS system is a highly effective method for individualized training to inoculate professionals against the negative consequences of stress, while teaching them to harness its positive effects. SRTS is a technology that can be widely applied to many professions that are concerned with well-being. We discuss applications to law enforcement, athletics, personal fitness and healthcare in the Appendix.

Keywords

Coherence coping performance individualized methods

1 Introduction

1.1 The military and PTSD

Serving in the military is arguably one of the most stressful occupations. The negative effects of stress can include decrements in immediate performance, psychological injuries leading to high risk behaviors such as alcohol and drug misuse, and in extreme cases, PTSD and suicide [1]. Therefore, developing service members’ resilience – their ability to withstand, recover, grow and adapt under stressful circumstances – is vital to protecting our military forces and has become a critical training objective for all military personnel [2]. Without resilience, service members’ performance will suffer and their fitness and readiness for deployment will be adversely affected [3].

1.2 Using stress for expert performance

Stress is a necessary part of learning and increasing strength [4], although there are limits to the amount of stress that is healthy. The Yerkes Dodson Law characterizes the relationship between stress and human performance as a U-shaped pattern, suggesting there is an optimal level of arousal after which stress produces detrimental effects [5]. Another model evaluating the relation between stress and arousal posits that the two are uncorrelated, suggesting instead that the relation depends on task demands and on intended behavior [6]. Further still, individual response to stress is infinitely variable owing to influences including genetics, age, and factors related to depletion such as diet and rest, yet strategies can be learned to reduce or mitigate the negative effects of stress and to accelerate recovery after stress exposure. Linear stage performance models of stress emphasize cognitive computation processing mechanisms and, in contrast, capacity models center on the strategic allocation of attentional and therefore energy-based resources to different mental functions [7]. The latter type of model focuses on the ability of humans to exert strategic control when faced with stressful situations [8, 9]. In this model, stress is cognitively appraised by assessing the required and available resources to cope with the immediate stressor. Strategies of choice include recruiting additional resources, removing the stressor, adapting strategically, or doing nothing. This model suggests that training for stress can be highly effective and that one can become adept at using stress for productive purposes. In terms of coping strategies, additional research in the context of employee-related stress suggests that perceived stress management may be influenced more by adaptive rather than maladaptive coping strategies [10].

Experienced personnel may be able to mitigate and even productively utilize stress. The seminal research in this domain showed that pilots conducting air-to-air combat in WWII had a significantly decreased chance of combat death or injury with repeated exposure [11]. This outcome was counterintuitive. For the raw recruits, the results were as expected: Higher reported stress and poorer performance in the ‘dangerous’ situation as compared to a control situation. Yet, for the experienced troops, the results were the opposite. These troops performed better in the ‘stressful’ situation than in the ‘non-stressful’ control situation, and reported more stress in the control situation than in the artillery situation. The results suggested that the experienced troops, while under dangerous friendly fire, utilized this additional stress positively to ameliorate the danger. A set of pioneering studies by Fenz et al. [12] also demonstrated this productive use of stress energy by expert and novice parachutists. Their work demonstrated that while expert and novice parachutists showed similar levels of stress, the timing of their peak levels of stress was the key differentiator. Specifically, experts reached peak levels of stress 24 hours prior to the jump, while novices’ stress levels peaked at the start of the jump. This finding suggests that experts, rather than failing to experience stress, do so at points where the resultant arousal is most likely to positively impact performance, i.e., in the preparation stage. By contrast, novices experience this arousal at points where it is most likely to negatively impact performance. Similar results were seen in a stress study conducted by the Army Research Institute [13], in which experienced personnel purportedly used stress energy to perform better in very realistically-simulated threat situations, while novices performed worse under the same conditions.

In summary, there exists ample evidence that experts experience stress differently than novices. Thus, a key hypothesis underlying the current solution proposed in this work is that the difference between the untrained novice and the experienced expert lies in how each manages similarly stressful situations. This is a marked departure from other models which assume that experts simply do not experience stress.

2 Graduated Stress Exposure and Stress Exposure Training

The concept of Stress Exposure Training (SET) was developed as an experiential learning approach to improve decision making under stress in US Navy combat teams [14]. The goal is to build individual and unit resilience and adaptability so stressors trigger effective stress coping skills rather than performance problems and stress injury. Research has shown that conventional training under extreme conditions on its own does not harden the warfighter to combat stressors and does not necessarily improve resilience and performance [15]. Instead, the research suggests that warfighters should first receive information about the stressors they will experience, and then practice training with techniques designed to manage them [15].

SET provides information, skills training, and practice to build capacity for coping and performance while exposed to stressors. Measures of attitudes and performance of trainees are used to provide immediate feedback and to measure learning outcomes. While Phase I of SET centers on a presentation of requisite knowledge – including typical reactions to stressors – the second and third phases include practice under graduated exposure to stressors; the number and types of stressors are gradually increased in successive training scenarios [14]. As alluded to above, SET comprises three phases that show improved self-confidence, critical thinking, stress management, and teamwork skills.

Phase I: Basic knowledge about stress and resilience. Trainees are informed of the training goals and the procedures that influence stress responses.

Phase II: Acquisition of skills for coping, decision-making and team adaptation to stress through practice and feedback. Addresses the physiological, emotional, social, cognitive, and performance components of stressors that are typically encountered on the job. Participants learn to self-regulate and to recognize the dysfunctional thoughts and emotions that diminish task performance and how to replace them with task-focused thoughts. These resilience skills create an integrated coping response to the physiological and cognitive outcomes of stress.

Phase III: Practicing the skills in a setting that simulates or reproduces the problem stressors. Skills are practiced under gradually increasing stressful conditions. Delivery modes can include simulated and/or real scenarios with after action reviews. Trainers coach trainees during live role-play or simulation of typical stressful situations to identify the critical points during stress exposure that should trigger the individual to use positive self-regulation skills. Trainees are encouraged to practice resilience building techniques at least once per day outside of the training environment and during typical stressful situations.

The SET construct allows for assessment and evaluation of individual performance at numerous points across the training. Attitudes and other psychological dimensions can be assessed along with Heart Rate Variability (HRV) baseline metrics (detailed in Section 3.4 below), at the inception of the training. Adherence to curriculum and performance of self-tests along the way can reveal the degree to which knowledge transfer has occurred. Performance of critical duty-related tasks is the most important but also can be the most difficult to measure.

3 The Stress Resilience Training System

We developed a stress resilience training system under the parent company of Perceptronics Solutions to help military service members build resilience. Our main objective in designing and developing the Stress Resilience Training System (SRTS) was to demonstrate that a software training app could provide an effective individualized method for mitigating the negative effects of situational and mission-related stress, while at the same time eliciting its potentially positive effects on performance. This objective was in line with the conclusions of an Institute of Medicine report, which recommended that the Department of Defense (DoD) employ only evidence-based resilience and prevention programs, and that it eliminate non-evidence-based programming [16]. The rationale provided in the report points to inconsistencies between the types of screening instruments employed throughout different points of the military life cycle, (i.e. accession, pre-deployment and deployment). Additionally, the report cites the lack of a routine health screening program intended for service members who are nearing separation from the military. Finally, non-validated instruments lead to a gap in a targeted intervention. Findings from validated screenings and risk assessments must be leveraged to mandate properly timed follow-up with targeted interventions for those individuals and families deemed at-risk [16]. The SRTS approach and app itself are described in the following section.

3.1 Resilience building approach

Building resilience results from the process of transforming resilience knowledge into measurable skills that can be strengthened through practice, then transferring those skills from practice sessions into life situations. As with physical fitness, the effectiveness of resilience skill practice increases as the intensity of the “workout” increases. In a physical fitness gym, adding extra weight or duration increases workout intensity. While each of the individual components of SRTS are explained in detail below in Section 3.3, as a general overview, SRTS gradually increases intensity by progressing from cognitive knowledge-based modules to biofeedback techniques modules and then to biofeedback-controlled games. These games increase neurocognitive demand beginning with simple biofeedback measures that a person learns to manipulate through self-regulation, then ratcheting up to maintenance of desired neurophysiological responses in games that require divided attention, motor coordination, and reaction times. The next challenge is to apply the “in-app” skills to simulated and actual life stressors. SRTS has been selected as a component of a US Army project that gradually increases stress exposure up to and including highly realistic combat simulations, with resilience skills embedded from classroom to battlefield. SRTS is also an ideal platform to deliver phased social stress exposure training. In fact, preparations are underway for that purpose in settings ranging from home use, to enhancing non-lethal law enforcement encounters, to use by those whose duties call them to areas of armed conflict. These include warfighters, peacekeepers, and caregivers, as well as those who provide humanitarian relief.

3.2 Coherence biofeedback

An essential part of the SRTS program is Heart Rate Variability (HRV) Coherence biofeedback and training, which employs techniques and processes developed and validated by Dr. Rollin McCraty and his colleagues at the Institute of Heartmath. McCraty et al. have demonstrated that the inter-beat interval pattern, or the heart rhythm, is strongly correlated with emotions and neurocognitive function [17]. They have developed the HRV Coherence method of HRV biofeedback to facilitate acquisition of self-regulation techniques that allow users to recognize and shift the mental and emotional responses associated with counter-productive stress reactions. Whereas basic HRV biofeedback encompasses exercises to increase absolute amount of beat-to-beat variability, HRV Coherence feedback focuses on shifting the pattern of the variability into one which is associated with optimal cognitive functioning.

The top graph of Fig. 1 shows the edgy, jerky HRV pattern associated with Incoherence. Incoherence reflects mainly that activity in the sympathetic and parasympathetic nervous systems are out of sync; it represents the neurophysiology of poor mental and physical performance. Overall, HRV Incoherence indicates a depleted state of psycho-physiological functioning. The bottom graph shows the more regular HRV pattern associated with HRV Coherence, when the sympathetic and parasympathetic nervous systems are operating harmoniously together. It represents the neurophysiology of optimal function, when everything seems easy, cognitive performance is enhanced and there is a general sense of well-being.

SRTS employs a sensor that applies HeartMath’s patented algorithms to pulse data in order to determine a numerical HRV Coherence score as a percentage between 0 and 100. The HRV Coherence score is calculated by analyzing the Power Spectral Density (PSD) of the HRV data, which indicates the power of the HRV waveform at various frequencies. The PSD is computed based on a Fast Fourier Transform, which performs a frequency domain analysis of the HRV data. The HRV Coherence score is created by quantifying the extent to which the power of the signal is spread across the range of frequencies. High Coherence will have the HRV signal clustered around a small band of frequencies; in contrast, low coherence will have a wide spread of peaks and valleys across the range of frequencies. The SRTS goal is to allow the user to both increase the absolute amount of HRV and to reach high levels of HRV Coherence.

3.3 iPad standalone application

The SRTS program comprises six key components: Know How, Techniques, Games, Review, Psychological Assessments and HRV Baselines, each described in detail below. As a self-contained, mobile training course, SRTS is available in formats compatible with both the iPad as well as the PC via internet connection. The application developed for the iPad is designed to combine: (1) information about the physiology of stress and resilience; (2) engaging training in a series of evidence-based energy self-regulation techniques; (3) assessments that indicate psychological well-being and improvements over time; and (4) the use of HRV Coherence biofeedback to control a series of progressively more challenging games that are designed to increase the utilization and sustainment of the resilience-building skills [18]. While the software can be intuitively self-guided, the system also provides an Adaptive Coach, which reminds the user of his or her progress, and recommends subsequent sections of the application to complete as the user advances.

The current SRTS application has a Navy orientation due to the early role of the Naval Center for Combat & Operational Stress Control (NCCOSC) as a major transition and evaluation partner. However, SRTS is readily adaptable to other stress-intensive professions such as law enforcement / first response, healthcare, and athletics.

3.3.1 Know How

This group of nine brief, narrated videos educates the user on stress and its effects. Module topics range from Resilience, Spiritual Fitness, Recognizing Stress, Performance, and Recovery, among others. Modules can be watched as many times as a user desires, and the time spent on each video is recorded for review. While most of the modules do not require participation from the user, a recently developed topic called “Building Resilience” solicits interaction from the user as a form of engaged learning. In an effort to individually tailor the content, questions throughout this module prompt a user to consider values and themes relevant to him or her, rather than objectively marking answers as correct versus incorrect.

3.3.2 Techniques

This selection of seven videos follows a similar format to the narrated Know How modules, while emphasizing science-based biofeedback techniques for energy management, based on self-regulation of HRV and shifts from negative to positive emotions. Module topics incorporated in this category include Baseline Shifting, Physiology of Stress, and Playing with Biofeedback, among others. Progress throughout these videos is similarly tracked and made available to the user, and any module can be revisited without limit.

3.3.3 Games

This section contains a set of five HRV-controlled games and simulations used to encourage practice of the biofeedback stress control techniques, hosting a series of engaging and progressively more challenging environments. The initial game is Basic Training, which introduces the user to the graphical and numerical feedback components. Subsequent games and simulations use the Basic Training elements as feedback. Users can accomplish greater performance in games by achieving higher HRV Coherence scores. Figure 2 shows the Asteroid Defense Game, in which users defend their city against incoming asteroids, and higher HRV Coherence translates to more ammunition. Additionally, a high-speed space driving game called “Slingshot” requires even greater coordinated skill, (see Fig. 2), as users navigate between lanes to avoid obstacles obstructing the path.

3.3.4 Review

This group of four quizzes, known as Resilience Checks allows the user to review his or her progress in learning HRV Coherence skills through the use of story-based self-tests and graphical visualizations of time-based performance measures.

3.3.5 Psychological assessments

In support of a one-year SRTS pilot project at Joint Task Force Guantanamo (JTFGTMO), Perceptronics Solutions– the developer of the SRTS product– partnered with psychologists from the Joint Stress Management and Restoration Training (JSMART) center at the detention facility in Guantanamo Bay, as well as personnel from the Naval Center for Combat and Operational Stress Control (NCCOSC) to select appropriate measures to include as assessment material within the SRTS application. Specifically, Table 1 indicates the measures and associated questionnaires created by GTMO and NCCOSC psychologists that have been included in the SRTS application for the JTFGTMO pilot project. Closely related to Service Member evaluations in development by NCCOSC for broad use in a variety of resilience programs, the assessments selected for this pilot project total 171 items (see Table 1). Questions vary between free-form text entry, subjective ratings on Likert scales, as well as other multiple choice selections.

3.4 HRV Baselines

Recent research literature indicates that basic HRV measures are good indicators of general neurophysiological health and resilience capacity [19, 20]. These measures include [19, 21]:

Mean Heart Rate, bpm

Mean Heart Rate Range (MHRR), bpm

Standard Deviation of RR Intervals (SDNN), ms

Root mean square of successive RR differences (RMSSD), ms

Accordingly, we included provision for obtaining these measures in the SRTS app as a means of initially assessing trainees and examining their status during and after training. An accurate baseline of short-term HRV protocols can be obtained in as little as one minute, with five minutes being a common standard in research studies with HRV used to examine emotional states [18, 22]. NCCOSC researchers have worked with Perceptronics Solutions to design and develop SRTS user interfaces for one-minute and five-minute deep breathing protocols to elicit the baseline HRV data, and have also worked with HeartMath to ensure that the information obtained from the HRV baselines is consistent with HeartMath’s studies. Figure 3 displays the user interface for the beginning of the one-minute protocol.

3.5 SRTS web version

Structured similarly to the standalone iPad application, the web version of SRTS has additional functionality, which aims to integrate the social component of coherence training. We expect the web version of SRTS to be widely adopted by populations that also seek to strengthen unit cohesion because this version emphasizes the social aspects of resilience training. The approach augments the objective of SRTS to destigmatize attention to psychological well-being – a crucial need throughout the military and in other environments where performance under high stress is critical. While this version may appeal to certain team-based audiences, users training with the stand alone iPad application have access to the same training modules and physiological components. The web-based program is currently compatible with both Windows and iOS operating systems, and we have plans to develop a hybrid application in the future that would offer the same functionality across platforms.

Upon entering the system, the user is greeted with an informational Dashboard (see Fig. 4), containing a recommendation from the Coach, as well as a series of six icons that graphically convey a user’s current progress through the system. Specifically, these items capture the status of the following themes: Daily and last-game-played Coherence, a weekly training goal, video progress, the most recent Resilience Check, and badges earned. Badges are rewarded for achieving particular milestones throughout training. While this feature is still in development, we expect to incorporate it in the iterative version alluded to above, which will be a cross-platform application. We anticipate that the process of earning badges and publicly sharing accomplishments will instill a sense of competition to boost interest and compliance among users.

Beyond the core functionality of the system, the user can also visit a personalized profile, which contains summaries of both Resilience Check and Module progress. Users training with SRTS as a part of a group will also have the ability to define “friends” who are other known SRTS users participating in the training. The personalized profile will also display any such friends. The web version enables users the capability to search for other users (see Fig. 4), and to view the basic details that comprise their respective profiles, including recent Coherence statistics, time spent training, and recent badges collected, as well as a list of any of their respective friends. The intent is to instill a sense of healthy competition to work toward achieving the highest coherence among a group of peers. Following a mutual friend request process, users are also granted functional access to six social communication action icons: Message, Respect, Challenge, Jab, Unfriend, and Block (Fig. 5). While this feature is also still under development, we expect it to incite the same general interest that similar features in popular social platforms like Facebook (https://www.facebook.com/) as well as self-quantifying fitness applications like FitBit (http://www.fitbit.com/) have evoked. To address privacy concerns, future versions of SRTS containingthese social features will provide a fine-grained permissions architecture. Sharing of information between friends will thus also have particular restrictions, allowing the user to specify what type of information can be public, and with whom it can be shared.

Both operating systems currently have the capacity to also support live chatting between and among devices, which mimics familiar instant-messaging technology (see Fig. 6). To prevent interruptions, notification balloons housed within a panel of the program keep track of social interactions that have been collected by the application while a user attends to another part of the system.

Future development of the web version of SRTS should provide links to common social networking applications such as Facebook. Users will also be able to access new features including competitions, forums and discussions to increase mastery of the system. Eventually, the program could also incorporate electronic payment capability for basic and additional features in order to expand and facilitate its widespread use.

4 Review of SRTS evaluations

The SRTS application was tested rigorously through several pilot training initiatives, usability studies and field trials to evaluate the usability and effectiveness of the tool. We were motivated by two primary questions: First, do users find the tool engaging, enjoyable and easy to use, and do they understand the techniques and knowledge presented in the application? Second, is SRTS effective in reliably increasing the HRV Coherence of a user and does using SRTS result in reduced stress? We conducted seven independent evaluations, which addressed one or a combination of these questions at the following sites: 1) George Mason University Usability Study, 2) Afghanistan Clinical Field Trial, 3) Air Force Evaluation Study, 4) Military Operational Medicine Research Program (MOMRP) Evaluation Study, 5) Naval Center for Operational Stress Control (NCCOSC) Evaluation Study, 6) San Diego Police Department (SDPD) Study and 7) Joint Task Force Guantanamo (JTFGTMO) Pilot Project 1 .

For all studies, SRTS was introduced with a brief training session lasting up to two hours. For usability studies, the users would engage with the tool for up to 90 minutes. Effectiveness studies involved one or more of the following components: a) pre vs. post-exposure surveys; b) mentors’ observations and users’ feedback; c) HRV physiological measurement; d) and SRTS usage data from embedded software. These lasted from six to eight weeks, some with a weekly one-hour mentor session by phone, using mentors trained by Institute of HeartMath.

4.1 High user engagement

User engagement with SRTS was high and the flexible approach of the application allowed for creative exploration of the system. Several usability studies were conducted on the iPad version and less formally on the web application of SRTS, using various methods to directly assess usability and user engagement [23 –26]. While exploring and interacting with the tool, users typically followed the Coach recommendations and watched each suggested video. A link analysis further revealed that users gravitated towards the Games section in both the iPad app and the web application (see Fig. 7), but sometimes skipped videos explaining the coherence concept, containing information that was critical to understanding the games. Users further rated the app highly on ease of use and speed of learning [23]. Behavioral results from an evaluation with Navy service members further indicated that users engaged in significantly more sessions with the application compared to the control condition, consisting of the standard progressive muscle relaxation application currently used in the Navy [24, 25]. Finally, a usability study found that participants with higher subjective resilience, as measured by the Response to Stressful Experience Scale (RSES), predicted that SRTS would be helpful to manage their stress (r = 0.72, p < 0.05) and would use the system more frequently (r = 0.75, p < 0.01) [23].

Users further reported verbally about the user-friendliness and user enjoyment of the tool, indicating that they enjoyed the simple user-interface, were intrigued by the concept, and enjoyed the games [25].

4.2 Reduced stress symptoms and increased HRV Coherence

In a number of preliminary studies, SRTS has been shown to improve clinical outcomes such as a reduction in self-reported stress, self-reported depression, increases in HRV Coherence and decreases in post-deployment PTSD symptoms. In a study with Navy service members, a group using SRTS showed a 29% reduction in perceived stress and a 47% reduction in perceived depression [24, 25]. A large military study showed that short time usage of SRTS resulted in a reduction of PTSD symptoms [25]. Anecdotal evidence from a small clinical field trial in Afghanistan further suggests that SRTS can be used effectively for personal mentoring in a clinical and educational setting for soldiers suffering from PTSD [25]. Use of SRTS with law enforcement personnel showed improvement on the Personal Organizational Quality Assessment (POQA) scale, particularly on the emotional vitality and physical stress subscales [26].

4.3 Discussion

Combined, these studies show substantial evidence for the efficacy of SRTS. Users are engaged with the application and appear to reduce stress subjectively, increase HRV Coherence, and improve outcomes on a number of standardized psychological assessment scales.

The evidence presented here supports the idea that users should actively engage in the process of stress inoculation– generally referring to prevention against its adverse effects– to increase their performance and well-being, rather than view stress as a weakness that needs to be treated. Programs that attempt to address psychological challenges within the military population are frequently met with resistance. This active, strength-building approach is fundamentally different from other applications and training curricula that instead emphasize relaxation and breathing exercises alone. Framing the tool as a way to use stress productively in order to enhance performance seems to resonate well within military and law enforcement populations.

A key insight from these evaluations is that the SRTS application works best in conjunction with mentoring and coaching. The built-in automated Coach was effective in navigating users through the app and was adjusted to ensure that users would be guided effectively through the curriculum. Personal mentoring was further effective in elaborating on the stress techniques described in the SRTS program and in relating the learned material to personal challenges. These multiple perspectives of using a person’s own motivation, guidance by an automated coach, and mentoring from a professional, increase the likelihood that a user will benefit from SRTS. We have further embraced this philosophy by incorporating social interaction in the web version, and we expect this will further enhance the experience and effectiveness ofSRTS.

Finally, SRTS does not just provide a way to cope with stress during actual use, but also produces lasting positive changes in individuals, which affect their professional lives. This evidence is mostly anecdotal and future research should address the effects of stress reduction on overall job performance. We discuss four applications of SRTS where we expect to see large differences in job performance in theAppendix.

5 Conclusions

The Stress Resilience Training System can provide an effective individualized method for mitigating the negative effects of situational and mission-related stress while at the same time eliciting its potentially positive effects on performance. Adaptations of SRTS to law enforcement, athletics, personal fitness and healthcare can have a substantial positive impact on job performance and overallwell-being.

Disclosures

The authors completed the ICMJE Form for Disclosure of Potential Conflicts of Interest and disclosed the funding described in the Acknowledgments section of this article. No other potential conflicts were disclosed.

Conflict of interest

The authors have no conflict of interest to report.

Footnotes

Appendix

1

IRB compliant protocols for these studies were arranged as follows: The GMU Usability Study (2012) used a George Mason University IRB-Approved Protocol. The Air Force Evaluation Study (2013) used an Air Force Research Laboratory (ARFL) IRB-Approved Protocol. The Naval Center for Operational Stress Control (NCCOSC) Evaluation Study (2013) used a Naval Medical Center San Diego (NMCSD) IRB. The Military Operational Medicine Research Program (MOMRP) Study (2013) used an Army Human Research Protection Office and the Central Arkansas Veterans Healthcare System Institutional Review Board. The remaining three preliminary trials did not need IRB approval because our product was incorporated into existing trainingregimens of the military and law enforcement, which have their own regulatory protocols for protecting their personnel: Afghanistan Clinical Field Trial; the San Diego Police Department Case Study (2013); and the 2015 Joint Task Force Guantanamo (JTFGTMO) Pilot Project.

Acknowledgments

Research, development and evaluation of SRTS were funded by the Defense Advanced Research Projects Agency (DARPA) through Small Business Innovation Research (SBIR) Phase I Contract N10PC20058 and Phase II Contract D11PC20125 as well as ONR BAA Contracts N00014-12-M-0198 and N00014-12-M-0408.

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