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Objective: This article advocates multidimensional assessment of task stress in human factors and reviews the use of the Dundee Stress State Questionnaire (DSSQ) for evaluation of systems and operators. Background: Contemporary stress research has progressed from an exclusive focus on environmental stressors to transactional perspectives on the stress process. Performance impacts of stress reflect the operator's dynamic attempts to understand and cope with task demands. Multidimensional stress assessments are necessary to gauge the different forms of system-operator interaction. Method: This review discusses the theoretical and practical use of the DSSQ in evaluating multidimensional patterns of stress response. It presents psychometric evidence for the multidimensional perspective and illustrative profiles of subjective state response to task stressors and environments. Evidence is also presented on stress state correlations with related variables, including personality, stress process measures, psychophysiological response, and objective task performance. Results: Evidence supports the validity of the DSSQ as a task stress measure. Studies of various simulated environments show that different tasks elicit different profiles of stress state response. Operator characteristics such as resilience predict individual differences in state response to stressors. Structural equation modeling may be used to understand performance impacts of stress states. Conclusion: Multidimensional assessment affords insight into the stress process in a variety of human factors contexts. Integrating subjective and psychophysiological assessment is a priority for future research. Application: Stress state measurement contributes to evaluating system design, countermeasures to stress and fatigue, and performance vulnerabilities. It may also support personnel selection and diagnostic monitoring of operators.

"The second edition of The Cambridge Handbook of Personality Psychology is a major update of the 2008 first edition. It is different in a number of crucial respects. Firstly, and most importantly, chapters are longer, more detailed and pitched at a higher level, which will better meet the needs of graduate students, researchers, and more seasoned academics. Secondly, there is now a more even and adequate coverage of the whole of personality psychology - not only compared to the first edition but, we believe, to similar handbooks on the market. Thirdly, the first edition had separate chapters on a number of psychopathological disorders; for conceptual depth and clarity, the second edition has fewer chapters of a more integrative and comprehensive character. They focus on the relationships between personality and clinical psychology, models of mental health, and anxiety, depression and cognitive dysfunction - there is also a related chapter on models of physical health. Lastly, some new topics have been added: accuracy in person perception, the unconscious, needs, goals and motivation, and social and economic behaviour"--

Objective: The aim of this study was to distill and define those influences under which change in objective performance level and the linked cognitive workload reflections of subjective experience and physiological variation either associate, dissociate, or are insensitive, one to another. Background: Human factors/ergonomics frequently employs users' self-reports of their own conscious experience, as well as their physiological reactivity, to augment the understanding of changing performance capacity. Under some circumstances, these latter workload responses are the only available assessment information to hand. How such perceptions and physiological responses match, fail to match, or are insensitive to the change in primary-task performance can prove critical to operational success. The reasons underlying these associations, dissociations, and insensitivities are central to the success of future effective human–machine interaction. Method: Using extant research on the relations between differing methods of workload assessment, factors influencing their association, dissociation, and insensitivity are identified. Results: Dissociations and insensitivities occur more frequently than extant explanatory theories imply. Methodological and conceptual reasons for these patterns of incongruity are identified and evaluated. Application: We often seek convergence of results in order to provide coherent explanations as bases for future prediction and practical design implementation. Identifying and understanding the causes as to why different reflections of workload diverge can help practitioners toward operational success.

The Handbook of Operator Fatigue provides a comprehensive account of this subject to serve as the definitive reference work for researchers, students and practitioners alike. The volume features 30 chapters written by experts to address each important facet of fatigue, including: the scale of the fatigue problem, the nature of fatigue, how to assess fatigue, the impact of fatigue on health, fatigue in the workplace, the neurological basis of fatigue, sleep disorders, and the design of countermeasures to fatigue

As cognitive models of behavior continue to evolve, the mechanics of cognitive exceptionality, with its range of individual variations in abilities and performance, remains a challenge to psychology. Reaching beyond the standard view of exceptional cognition equaling superior intelligence, the Handbook of Individual Differences in Cognition examines the latest findings from psychobiology, cognitive psychology, and neuroscience, for a comprehensive state-of-the-art volume. Breaking down cognition in terms of attentional mechanisms, working memory, and higher-order processing, contributors discu.

Objective This study tested whether indices of executive control, alertness, and orienting measured with Attention Network Test (ANT) are vulnerable to temporal decrement in performance. Background Developing the resource theory of sustained attention requires identifying neurocognitive processes vulnerable to decrement. Executive control processes may be prone to impairment in fatigue states. Such processes are also highlighted in alternative theories. Determining the role of executive control in vigilance can both advance theory and contribute to practical countermeasures for decrement in human factors contexts. Method In Study 1, 80 participants performed the standard ANT for an extended duration of about 55 to 60 min. Study 2 (160 participants) introduced manipulations of trial blocking and stimulus degradation intended to increase resource depletion. Reaction time and accuracy measures were analyzed. Subjective stress and workload were assessed in both studies. Results In both studies, the ANT induced levels of subjective workload and task disengagement consistent with previous sustained attention studies. No systematic decrement in any performance measure was observed. Conclusion Executive control assessed by the ANT is not highly vulnerable to temporal decrement, even when task demands are elevated. Future work should differentiate executive control processes; proactive control may be more implicated in sustained attention decrement than in reactive control. Application Designing systems and interfaces to reduce executive control demands may be generally beneficial but will not directly mitigate temporal performance decrement. Enhancing design guidelines and neuroergonomic methods for monitoring operator attention requires further work to identify key neurocognitive processes for decrement.

Objective: We describe major discoveries and developments in vigilance research. Background: Vigilance tasks have typically been viewed as undemanding assignments requiring little mental effort. The vigilance decrement function has also been considered to result from a decline in arousal brought about by understimulation. Methods: Recent research in vigilance is reviewed in four areas: studies of task type, perceived mental workload during vigilance, neural measures of resource demand in vigilance, and studies of task-induced stress. Results: Experiments comparing successive and simultaneous vigilance tasks support an attentional resource theory of vigilance. Subjective reports also show that the workload of vigilance is high and sensitive to factors that increase processing demands. Neuroimaging studies using transcranial Doppler sonography provide strong, independent evidence for resource changes linked to performance decrement in vigilance tasks. Finally, physiological and subjective reports confirm that vigilance tasks reduce task engagement and increase distress and that these changes rise with increased task difficulty. Conclusions: Converging evidence using behavioral, neural, and subjective measures shows that vigilance requires hard mental work and is stressful. Application: This research applies to most human-machine systems that require human monitoring, particularly those involving automated subsystems.

Almost from its inception, the emotional intelligence (EI) construct has been an elusive one. After nearly 2 decades of research, there still appears to be little consensus over how EI should be conceptualized or assessed and the efficacy of practical applications in real life settings. This paper aims at providing a snapshot of the state-of-the-art in research involving this newly minted construct. Specifically, in separate sections of this article, we set out to distinguish what is known from what is unknown in relation to three paramount concerns of EI research, i.e., conceptualization, assessment, and applications. In each section, we start by discussing assertions that may be made with some degree of confidence, elucidating what are essentially sources of consensus concerning EI. We move then to discuss sources of controversy; those things for which there is less agreement among EI researchers. We hope that this "straight talk" about the current status of EI research will provide a platform for new research in both basic and applied domains.

Objective: Two studies tested multivariate models of relationships between subjective task engagement and vigilance. The second study included a stress factor (cold infection). Modeling tested relationships between latent factors for task engagement and vigilance, and the role of engagement in mediating effects of cold infection. Background: Raja Parasuraman's research on vigilance identified several key issues, including the roles of task factors, arousal processes, and individual differences, within the framework of resource theory. Task engagement is positively correlated with performance on various attentional tasks and may serve as a marker for resource availability. Method: In the first study, 229 participants performed simultaneous and successive vigilance tasks. In the second study, 204 participants performed a vigilance task and a variable-foreperiod simple reaction-time task on two separate days. On the second day, 96 participants performed while infected with a naturally occurring common cold. Task engagement was assessed in both studies. Results: In both studies, vigilance decrement in hit rate was observed, and task performance led to loss of task engagement. Cold infection also depressed both vigilance and engagement. Fitting structural equation models indicated that simultaneous and successive tasks should be represented by separate latent factors (Study 1), and task engagement fully mediated the impact of cold infection on vigilance but not reaction time (Study 2). Conclusions: Modeling individual differences in task engagement elucidates the role of resources in vigilance and underscores the relevance of Parasuraman's vision of the field. Application: Assessment of task engagement may support diagnostic monitoring of operators performing tasks requiring vigilance.

Objective: A study was run to test which of five electroencephalographic (EEG) indices was most diagnostic of loss of vigilance at two levels of workload. Background: EEG indices of alertness include conventional spectral power measures as well as indices combining measures from multiple frequency bands, such as the Task Load Index (TLI) and the Engagement Index (EI). However, it is unclear which indices are optimal for early detection of loss of vigilance. Method: Ninety-two participants were assigned to one of two experimental conditions, cued (lower workload) and uncued (higher workload), and then performed a 40-min visual vigilance task. Performance on this task is believed to be limited by attentional resource availability. EEG was recorded continuously. Performance, subjective state, and workload were also assessed. Results: The task showed a vigilance decrement in performance; cuing improved performance and reduced subjective workload. Lower-frequency alpha (8 to 10.9 Hz) and TLI were most sensitive to the task parameters. The magnitude of temporal change was larger for lower-frequency alpha. Surprisingly, higher TLI was associated with superior performance. Frontal theta and EI were influenced by task workload only in the final period of work. Correlational data also suggested that the indices are distinct from one another. Conclusions: Lower-frequency alpha appears to be the optimal index for monitoring vigilance on the task used here, but further work is needed to test how diagnosticity of EEG indices varies with task demands. Application: Lower-frequency alpha may be used to diagnose loss of operator alertness on tasks requiring vigilance.

Objective: A driving simulator was used to assess the impact on fatigue, stress, and workload of full vehicle automation that was initiated by the driver. Background: Previous studies have shown that mandatory use of full automation induces a state of "passive fatigue" associated with loss of alertness. By contrast, voluntary use of automation may enhance the driver's perceptions of control and ability to manage fatigue. Method: Participants were assigned to one of two experimental conditions, automation optional (AO) and nonautomation (NA), and then performed a 35-min, monotonous simulated drive. In the last 5 min, automation was unavailable and drivers were required to respond to an emergency event. Subjective state and workload were evaluated before and after the drive. Results: Making automation available to the driver failed to alleviate fatigue and stress states induced by driving in monotonous conditions. Drivers who were fatigued prior to the drive were more likely to choose to use automation, but automation use increased distress, especially in fatigue-prone drivers. Drivers in the AO condition were slower to initiate steering responses to the emergency event, suggesting optional automation may be distracting. Conclusion: Optional, driver-controlled automation appears to pose the same dangers to task engagement and alertness as externally initiated automation. Application: Drivers of automated vehicles may be vulnerable to fatigue that persists when normal vehicle control is restored. It is important to evaluate automated systems' impact on driver fatigue, to seek design solutions to the issue of maintaining driver engagement, and to address the vulnerabilities of fatigue-prone drivers.

Three studies are reported of individual differences in performance of high event rate vigilance tasks. In each study, measures of attentional resource availability and elementary cognitive components of sustained attention were correlated with vigilance performance. It was predicted that correlates of vigilance should vary with two parameters of the task: the type of target discrimination required (simultaneous or successive) and the type of stimuli used (sensory or symbolic). Speed and accuracy of controlled, resource-demanding visual search predicted overall perceptual sensitivity on three out of four successive tasks used, but only one out of four simultaneous tasks, partially confirming the hypothesis that successive tasks are more strongly resource-limited than simultaneous tasks. Other correlates of overall level vigilance did not appear to vary systematically with task parameters. Few correlates of temporal decrement in perceptual sensitivity were found, possibly for statistical reasons. The data suggest that measures of controlled search may be useful in predicting vigilance on certain real-world tasks, although a substantial part of the variance of vigilance tasks may not be predictable fromts short cognitive tasks.