Exploring heart rate variability as a human performance optimisation metric for law enforcement

Tactical personnel, inclusive of police officers, face complex challenges over potentially decades-long careers. These cumulative exposures may manifest as allostatic load, impairing health, fitness, and performance. Allostatic load describes increased vulnerability to psychophysiological dysfunction resulting from prolonged overstress exposure. Monitoring for this risk is an important step towards its mitigation. Heart rate variability (HRV) analysis can noninvasively acquire psychophysiological overstress information in tactical environments. HRV theory and principles are well established, however, the integration of HRV in tactical workflows, especially for end-users, has received limited research attention. Therefore, the overarching aim of this programme of research was to determine the utility of HRV assessment in the support of specialist police and their organisations and to alert stakeholders to potential instances of psychophysiological overstress. Chapter 1 introduces HRV concepts within tactical contexts. Components of tactical work that may be best appreciated with HRV analysis are highlighted. Principles in this introduction are further articulated in a systematic review (Chapter 2). Chapter 2 reports on the undertaken systematic review which summarised and critically appraised studies of HRV applications across tactical populations. Of 296 initially identified studies, twenty were included. The volume of evidence suggested that HRV effectively supports health and performance measures in tactical environments. However, literature gaps were identified; most notably, there was limited evidence available regarding HRV in specialist police professions, thus warranting this research. As professional requirements and potential allostatic load sources differ during specialist police selection and subsequent specialist police operational contexts, two research arms were devised to pragmatically address this critical gap. Chapter 3 illustrates the research structure in further detail and outlines which studies address specific literature gaps within specialist police and in which of the two developed research arms. Methodological approaches are also described. Chapters 4, 5, 6, and 7 encompass HRV application in initial specialist police selection. Chapter 4 introduces the first field study, building on the findings from Chapter 2 (Studyiii1) that HRV assessment may be more valuable than traditional heart rate (HR)measurement for monitoring tactical training as HRV is capable of measuring stress holistically. The primary aim therefore was to investigate whether HRV was more sensitive than HR at monitoring workload during specialist police selection activities. As aerobic fitness is associated with workload during these tasks, a secondary aim was to investigate relationships between HRV, HR, and maximal aerobic fitness. As illustrated by a time-series plot, HR values were unremarkable while HRV values were potentially depressed, and tentatively indicative of overstress. Estimated maximal aerobic fitness (20-m shuttle run) was significantly positively correlated with HRV, but there was no relationship with HR. When a linear regression model was applied, neither HRV nor HR were predicted by 20-m shuttle run scores. Chapter 5 aimed to determine the effectiveness of HRV in differentiating between candidates that failed to complete specialist selection from those who succeeded. HRV was defined as the percentage of R-R intervals that varied by at least 50ms (pRR50). Data were summarised in a heat map. A logistic regression model was generated that effectively predicted attrition but did not identify the most successful candidate. Therefore, the aim of Chapter 6 was to profile HRV characteristics of that successful candidate and consequently a detailed HRV time series plot was generated. Contextual analysis was applied, and the candidate demonstrated continued performance even under apparent duress, both physical and psychological in nature. The subsequent studies (7-9)then aimed to consider HRV monitoring at the operational level where such duress exposures occur frequently. Noting that success in training is distinct from operational performance, Chapters 7, 8, 9,and 10 examined the use of HRV monitoring in operational contexts. The purpose of Chapter 7 was to identify if HRV analysis could classify candidate performance in specialist police selection during occupationally realistic tactical operations scenarios which required fluid psychomotor skills, teamwork, and leadership while under duress. Qualitative analysis of descriptive statistics indicated that the HRV data of one participant were substantially different from his peers. This candidate was also the highest performer, suggesting a relationship between HRV and occupational aptitude. Given that specialist police often work rotating shift schedules which may lead to sleep deprivation, introducing another source of allostatic load, the aim of Chapter 8 was to determine the extent to which HRV may detect differences between specialist police that worked an overnight shift and those that were off duty overnight. HRV was analysed in11 male specialist police officers who were either off-duty or on overnight duty prior to engaging in specialist assessment activities. All officers experienced HRV perturbations from the assessment, but post-assessment HRV was greater amongst those who were coming on duty. HRV values continued to decline after assessment success amongst those that worked the night prior to training, potentially indicating greater stress loads in those that worked the overnight shift. Chapter 9 further explored HRV changes observed in Chapter 8. The aim was to identify relationships between physical fitness as measured by completion time on a primarily anaerobic occupational obstacle course, and HRV response during firearms qualification and subsequent stress training. HRV was assessed as the within-operator change from pre- to post-qualification and post-training. HRV was reduced after training but not after qualification. A linear regression model indicated that obstacle course completion time predicted HRV changes from baseline to both post-qualification and post-training. While stressful training and overnight shifts are regularly encountered in specialist police work, other tasks, such as serving in Directing Staff (DS) roles on selection courses for future candidates are also important duties and present as a nexus between operations and selection. Thus, Chapter 10 considered the critical operational role of DS cadre. The purpose of this study was to monitor and analyse the HRV of one DS member during their 24-hour shift on a candidate selection course. The findings of this case study suggested that DS may be subject to stress levels not unlike those of candidates. This is of note as selection courses are highly taxing and arduous, and officers may serve as DS on more than one course per year and still be required to perform their operational duties.DS requirements during selection courses should therefore be considered appropriately in the overall deployment and operational task scheduling paradigm.Each previous chapter considered important elements of service in a specialist police organisation. The final chapter (Chapter 11) summated the findings from this programme of study, contextualised the works in terms of the bodies of literature with which they were most associated, and highlighted overall limitations as well as plausible future directions. A final supplementary chapter, aimed to provide an operational guide for utilising HRV data in tactical settings, contributed to further support translation of research to practice. In this supplementary chapter, shortcomings of using HRV were reviewed and solutions to avoid flawed analysis provided, as are the key lessons learned from this thesis. In essence, the presentation and visualisation of HRV data may be as critical to the application of HRV analysis as the measurements themselves in tactical settings

AlphaStar: Considerations and Human-like Constraints for Deep Learning Game Interfaces

Games have historically been a fruitful area for artificial intelligence (AI) research, and StarCraft in particular has been an important grand challenge because of its strategic complexity, multi-agent dynamics, partial observability, large action spaces, delayed rewards, and robust human competitive scene. These complexities mean that approaches common in other game AIs, like Monte-Carlo Tree Search in Go or searching over the action space in Atari, cannot be easily applied to StarCraft. Thus, though there has been significant research, many approaches use handcrafted systems and no approach is competitive with even strong casual players. In this thesis, we go into detail on AlphaStar, the first AI system to reach the highest tier of human performance in a widely professionally played esport. AlphaStar combines new and existing approaches in imitation learning, reinforcement learning, and multi-agent learning at scale in a general agent with minimal handcrafting. AlphaStar reached a rating above 99.8% of active ranked human players. In particular, designing an effective interface is an essential component of AI research in games that has historically been under-explored. This thesis lists principles for designing effective interfaces and human-like constraints for deep learning research in games, and explores those principles with AlphaStar as a case study. Though the agent has minimal handcrafting, it needs to interact with the game through an interface that is human-like, expressive enough to capture the game's complexities, and amenable to deep learning in order to produce transferable research insights

Respuesta Psicofisiológica ante el Uso Militar del Traje NBQR: Una Propuesta de Intervención y Preparación

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Formación del Profesorado y Educación. Fecha de Lectura: 29-06-2021La tesis doctoral que a continuación se presenta estudia las diferencias fisiológicas, cognitivas y conductuales que conlleva portar un equipo de protección nuclear, biológico, químico y radiológico y realizar tareas sanitario-militares en estas condiciones. En esta tesis, se analiza si la realización de un protocolo de entrenamiento de alta intensidad por intervalos de tiempo podría ofrecer beneficios a los profesionales/combatientes que precisan llevar puestos estos equipos en el cometido de sus labores o para cumplir su misión. Los participantes realizaron una serie de tareas sanitario-militares con estos equipos, determinando cuáles eran las afectaciones que se producían a nivel fisiológico, cognitivo y conductual. Tras someterse a un entrenamiento de alta intensidad por intervalos de tiempo durante seis semanas, se volvió a determinar qué afectaciones se encontraban en el desarrollo de las mismas labores, detectando que fisiológicamente niveles de lactato, fuerza explosiva de tren inferior y fuerza manual mejoraron, conductualmente no se obtuvieron beneficios con este tipo de entrenamiento y a nivel cognitivo el esfuerzo percibido del que partían antes de realizar el estudio era inferior al presentado antes del entrenamiento

Digital games: motivation, engagement and informal learning

This thesis investigates the relationships between motivation, engagement and informal learning, with respect to digital games and adult players. Following the reconceptualisation of motivation and engagement (as forms of micro and macro level involvement respectively) three linked studies were conducted. In the first study, 30 players were interviewed via email about their gaming experiences. The resulting set of learning categories and themes drew attention to learning on a game, skill and personal level, which arose from micro-level gameplay and macro-level interaction with wider communities and resources. The second investigation consisted of eight case studies that examined how involvement and learning come together in practice. Participants were observed in the lab during two gameplay sessions and kept gaming diaries over a three week period. A method for categorising game-play breakdowns and breakthroughs (relating to action, understanding and involvement) was developed in order to analyse several hours of gameplay footage. The previous categories and themes were also applied to the data. The findings suggested a relationship between macro-involvement and player identity, which was further investigated by a third survey study (with 232 respondents). The survey helped to establish a link between identity, involvement, and learning; the more strongly someone identifies as a gamer, the more likely they are to learn from their involvement in gaming practice. Four main contributions are presented: (1) an empirical account of how informal learning occurs as a result of micro and macro-involvement within a gaming context, (2) an in-depth understanding of how breakdowns and breakthroughs relate to each other during play, (3) a set of categories that represent the range of learning experienced by players, and (4) a consideration of the role player identity serves with respect to learning and involvement