Predicting vigilance: a fresh look at an old problem

The strategic allocation theory of vigilance

Despite its importance in different occupational and everyday contexts, vigilance, typically defined as the capacity to sustain attention over time, is remarkably limited. What explains these limits? Two theories have been proposed. The Overload Theory states that being vigilant consumes limited information-processing resources; when depleted, task performance degrades. The Underload Theory states that motivation to perform vigilance tasks declines over time, thereby prompting attentional shifts and hindering performance. We highlight some conceptual and empirical problems for both theories and propose an alternative: the Strategic Allocation Theory. For the Strategic Allocation Theory, performance on vigilance tasks optimizes as a function of intrinsic and extrinsic motivations, including metacognitive factors such as the expected value of effort and the expected value of planning. Limited capacities must be deployed across task sets to maximize expected reward. The observed limits of vigilance reflect changes in the perceived value of, among other things, sustaining attention to a task rather than attending to something else. Drawing from recent computational theories of cognitive control and meta-reasoning, we argue that the Strategic Allocation Theory explains more phenomena related to vigilance behavior than other theories, including self-report data. Finally, we outline some of the testable predictions the theory makes across several experimental paradigms. This article is categorized under: Philosophy > Foundations of Cognitive Science Psychology > Attention.

Self-control enhances vigilance performance in temporally irregular tasks: an fNIRS frontoparietal investigation

The present study investigated whether trait self-control impacted operators' behavior and associated neural resource strategies during a temporally irregular vigilance task. Functional near-infrared spectroscopy (fNIRS) readings of oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (HbR) from 29 participants were recorded fromthe prefrontal and parietal cortices. Self-control was associated with better perceptual sensitivity (A') in the task with the irregular event schedule. A left-lateralized effect of HbO2 was found for temporal irregularity within the dorsomedial prefrontal cortex, in accordance with functional transcranial doppler (fTCD) studies. Self-control increased HbR (decreasing activation) at right superior parietal lobule (rSPL; supporting vigilance utilization) and right inferior parietal lobule (rIPL; supporting resource reallocation). However, only rSPL was associated with the vigilance decrement-where decreases in activation led to better perceptual sensitivity in the temporally irregular task. Additionally, short stress-state measures suggest decreases in task engagement in individuals with higher self-control in the irregular task. The authors suggest a trait-state-brain-behavior relationship for self-control during difficult vigilance tasks. Implications for the study include steps toward rectifying the resource utilization vs. allocation debate in vigilance-as well as validating HbO2 and HbR as effective constructs for predicting operators' mental resources through fNIRS.

A video processing and machine learning based method for evaluating safety-critical operator engagement in a motorway control room

In safety-critical automatic systems, safety can be compromised if operators lack engagement. Effective detection of undesirable engagement states can inform the design of interventions for enhancing engagement. However, the existing engagement measurement methods suffer from several limitations which damage their effectiveness in the work environment. A novel engagement evaluation methodology, which adopts Artificial Intelligence (AI) technologies, has been proposed. It was developed using motorway control room operators as subjects. Openpose and Open Source Computer Vision Library (OpenCV) were used to estimate the body postures of operators, then a Support Vector Machine (SVM) was utilised to build the engagement evaluation model based on discrete states of operator engagement. The average accuracy of the evaluation results reached 0.89 and the weighted average precision, recall, and F1-score were all above 0.84. This study emphasises the importance of specific data labelling when measuring typical engagement states, forming the basis for potential control room improvements.Practitioner summary: This study demonstrates an automatic, real-time, objective, and relatively unobtrusive method for measuring dynamic operator engagement states. Computer vision technologies were used to estimate body posture, then machine learning (ML) was utilised to build the engagement evaluation model. The overall evaluation shows the effectiveness of this framework.Abbreviations: AI: Artificial Intelligence; OpenCV: Open Source Computer Vision Library; SVM: Support Vector Machine; UWES: Utrecht Work Engagement Scale; ISA Engagement Scale: Intellectual, Social, Affective Engagement Scale; DSSQ: Dundee Stress State Questionnaire; SSSQ: Short Stress State Questionnaire; EEG: electroencephalography; ECG: Electrocardiography; VMOE: Video-based Measurement for Operator Engagement; CMU: Carnegie Mellon University; CNN: Convolutional Neural Network; 2D: two dimensional; ML: Machine learning.

Testing the modulation of self-related automatic and others-related controlled processing by chronotype and time-of-day

We assessed whether self-related automatic and others-related controlled processes are modulated by chronotype and time-of-day. Here, a shape-label matching task composed of three geometrical shapes arbitrarily associated with you, friend, and stranger was used. Twenty Morning-types, and twenty Evening-types performed the task at the optimal and non-optimal times of day (i.e., 8 AM, or 8:30 PM). Morning-types did not exhibit noticeable synchrony effects, thus proving the better adaptation of these participants to non-optimal moments of the day as compared to Evening-types. Contrary to our predictions regarding the absence of automatic-processing modulation and the presence of controlled-processing influences by time-of-day, we found an influence on self-related but not others-related processing only in Evening-type participants. Although brain structures are not directly tackled, we argue that such modulation may be due to the dependence of the activation of the ventromedial prefrontal cortex (VMPFC), an essential component of the self-attention network on circadian rhythms.

Driver Vigilance Decrement is More Severe During Automated Driving than Manual Driving

OBJECTIVE

The present study compared the performance, workload, and stress associated with driver vigilance in two types of vehicle: a traditional, manually operated vehicle, and a partially automated vehicle.

BACKGROUND

Drivers of partially automated vehicles must monitor for hazards that constitute automation failures and the need for human intervention, but recent research indicates that a driver's ability to do so declines as a function of time. That research lacked a comparison measure of driving without vehicle automation, so it is unknown to what degree these effects are specific symptoms of monitoring the roadway during an automated drive. Drivers in manual control of their vehicle must similarly monitor for hazards and may suffer similar vigilance decrements.

METHOD

Participants completed a simulated 40-minute drive while monitoring for hazards. Half of participants completed the drive with an automated driving system that maintained speed and lane position; the remaining half manually controlled the vehicle's speed and lane position.

RESULTS

Driver sensitivity to hazards decreased and tendency to make false alarms increased over time in the automated control condition, but not in the manual control condition. Drivers in both conditions detected fewer hazards as the drive progressed. Ratings of workload and task-induced stress were elevated similarly in both conditions.

CONCLUSION

Partially automated driving appears to uniquely impair driver vigilance by reducing the ability to discriminate between benign and dangerous events in the driving environment as the drive progresses.

APPLICATION

Applied interventions should target improvements in driver sensitivity to hazardous situations that signal potential automation failures.

A review of cyber vigilance tasks for network defense

The capacity to sustain attention to virtual threat landscapes has led cyber security to emerge as a new and novel domain for vigilance research. However, unlike classic domains, such as driving and air traffic control and baggage security, very few vigilance tasks exist for the cyber security domain. Four essential challenges that must be overcome in the development of a modern, validated cyber vigilance task are extracted from this review of existent platforms that can be found in the literature. Firstly, it can be difficult for researchers to access confidential cyber security systems and personnel. Secondly, network defense is vastly more complex and difficult to emulate than classic vigilance domains such as driving. Thirdly, there exists no single, common software console in cyber security that a cyber vigilance task could be based on. Finally, the rapid pace of technological evolution in network defense correspondingly means that cyber vigilance tasks can become obsolete just as quickly. Understanding these challenges is imperative in advancing human factors research in cyber security.

CCS categories

Human-centered computing~Human computer interaction (HCI)~HCI design and evaluation methods.

Reacting and responding to rare, uncertain and unprecedented events

This work examines how we may be able to anticipate, respond to, and train for the occurrence of rare, uncertain, and unexpected events in human-machine systems operations. In particular, it uses a foundational matrix which describes the combinations of the state-of-the-world and the state-of-the-respondent, to formulate preferred response strategies, contingent upon what is knowable and actionable in each circumstance. It employs the dichotomy of System I and System II forms of cognitive response and augments these perspectives with a further form of decision-making, namely Systems III. The latter is predicated upon reactions to novel, unprecedented, and even 'unthinkable' events. The degree to which any human operator, the associated automation and/or the autonomy of a system, or each of these acting in concert, can best deal with these 'blue swan' events is explored. Potential forms of remediation, especially featuring training, are discussed, and evaluated in light of the skills needed to respond to even prohibitive degrees of situational uncertainty.Practitioners summary: Practitioners are liable to witness a growing spectrum of unusual and, on occasion, even unprecedented events in the operation of systems for which they are responsible. They will be required to account for their response to these circumstances to a spectrum of involved constituencies to whom they answer. This work aids them in succeeding to bring clarity to such difficult and challenging processes.Abbreviations: K: Known; Unk: Unknown; AI: Artificial Intelligence; ML: Machine Learning; CHARM: Cockpit Human-Automation Resource Management; SDT: signal detection theory; ASRS: Aviation Safety Reporting System.

Gaming experience predicts UAS operator performance and workload in simulated search and rescue missions

Unmanned aircraft systems (UAS) operator training and selection procedures are still being refined to effectively address challenges related to performance, workload, and stress in UAS operation. Research suggests that experience with commercial videogames may test skills relevant to modern UAS operation. This study investigated the ability of videogame experience to predict operator performance, workload, and stress. Forty-nine participants performed 9 trials of a simulated search and rescue mission. It was expected that participants who more frequently played videogames would report lower levels of distress and workload, higher task engagement, and better overall performance. Results showed that gaming experience was negatively correlated with subjective workload and positively correlated with multiple measures of performance. Furthermore, nearly all observed gender-related differences were not present when gaming experience was controlled for. These results have implications for the role of gaming experience in remotely operated systems operator recruitment, selection, and training. Practitioner summary: This study examined how gaming experience influences UAS operator success in simulated search and rescue missions. Participants reported on their experience playing videogames before completing multiple experimental trials on a desktop computer. Results indicated that experience playing videogames significantly impacted performance, workload, and stress.

Measuring Failures Proneness: Scale Development and Preliminary Validations

Behavioral failures can serve as precursors for accidents. Yet, individual differences in the predisposition to behavioral failures have predominantly been investigated within relatively narrow parameters, with the focus limited to subsets of behaviors or specific domains. A broader perspective might prove useful in illuminating correlations between various forms of accidents. The current research was undertaken as one step toward developing the concept of behavioral failures proneness in its multidimensional aspect. We report the initial stage of the development and validation of the Failures Proneness questionnaire (FP): a brief, multifaceted, self-report scale of common behavioral failures in everyday settings. In a preliminary phase we conceived an extensive pool of prospective items. Study 1 identified and validated the factor-structure of FP and reduced the scale to a brief measure of 16 items. Study 2 corroborated the factor structure of the FP and evaluated its construct validity by assessing its relationship with the Five Factor Model (FFM) of personality traits. Study 3 tested the criterion-related validity of the FP by assessing its ability to predict deviant behaviors. These studies provide evidence of the FP's performance in generating valuable information on a broad range of behavioral antecedents of accidents.

Workforce perceptions of human factors as indicators of plant reliability and process safety

Human factors, as perceived by the maintenance workforce, were used as the measure for comparing work areas within a petroleum company. These factors were then compared to an objective measure of reliability (Mean Time Between Failures) in order to determine which factors would be most predictive of plant reliability and process safety. Maintenance personnel were surveyed using scales based on Problem-solving, Vigilance, Design and maintenance, Job-related feedback and Information about change. Analysis of Variance was used to assess the strength of these variables in relation to Reliability Level. Significant differences were observed between different reliability levels based on workforce perceptions of problem-solving requirements and the design and maintainability of plant. Conclusions were that perceptions of human factors in the workplace can be predictive of group-level performance, and that if issues relating to design and maintainability are not addressed at the design stage, greater problem-solving abilities will be required from maintenance personnel. Practitioner summary: Workforce perceptions of plant performance could provide a statistically valid measure of current and future reliability. A survey of perceptions of human factors was conducted with maintenance personnel in a petroleum company. Results indicated significant relationships between reliability and requirements for Problem-solving, as well as Design and Maintenance of equipment. Abbreviations: HFIT: human factors investigation tool, FPSO: floating production, storage and offtake, MTBF: mean time between failures, CPS: cognitive problem- solving, WDS: work design questionnaire, SPSS: statistical package for the social sciences, PAF: principal axis factoring, ANOVA: analysis of variance, ANCOVA: analysis of co-variance, M: mean, SD: standard deviation.

Where is my mind? Examining mind-wandering and vigilance performance

Vigilance is the ability to sustain attention to information for prolonged periods of time, particularly in environments where critical signals may be rare. Recent research in the domain of mind-wandering has suggested that processes associated with mind-wandering may underpin the typical decline in vigilance task performance. Current methods for measuring mind-wandering either disrupt vigils by asking probe questions throughout the task, or, require observers to reflect on how much mind-wandering occurred during the task upon conclusion of the vigil. Across three experimental studies, we treat mind-wandering as an individual difference, which was measured pre- and post-vigil. We argue this technique is a more holistic representation of mind-wandering and is less intrusive than probe measures, which serve to disrupt the vigil. The results of our first experiment challenge previous results in the literature: higher rates of mind-wandering were associated with improved correct detection performance. Interestingly, the second experiment suggests that increases in mind-wandering were not linked to vigilance performance deficits. However, significant differences in global workload emerged in the second experiment, implying individuals low in mind-wandering report greater workload. In a third experiment, wherein we manipulated event rate, mind-wandering typology had no significant effect on vigilance performance. We conclude with a discussion of the relevance of individual differences in mind-wandering in vigilance research considering the present findings.

Positive valence music restores executive control over sustained attention

Music sometimes improves performance in sustained attention tasks. But the type of music employed in previous investigations has varied considerably, which can account for equivocal results. Progress has been hampered by lack of a systematic database of music varying in key characteristics like tempo and valence. The aims of this study were to establish a database of popular music varying along the dimensions of tempo and valence and to examine the impact of music varying along these dimensions on restoring attentional resources following performance of a sustained attention to response task (SART) vigil. Sixty-nine participants rated popular musical selections that varied in valence and tempo to establish a database of four musical types: fast tempo positive valence, fast tempo negative valence, slow tempo positive valence, and slow tempo negative valence. A second group of 89 participants performed two blocks of the SART task interspersed with either no break or a rest break consisting of 1 of the 4 types of music or silence. Presenting positive valence music (particularly of slow tempo) during an intermission between two successive blocks of the SART significantly decreased miss rates relative to negative valence music or silence. Results support an attentional restoration theory of the impact of music on sustained attention, rather than arousal theory and demonstrate a means of restoring sustained attention. Further, the results establish the validity of a music database that will facilitate further investigations of the impact of music on performance.

Latent error detection: A golden two hours for detection

Undetected error in safety critical contexts generates a latent condition that can contribute to a future safety failure. The detection of latent errors post-task completion is observed in naval air engineers using a diary to record work-related latent error detection (LED) events. A systems view is combined with multi-process theories to explore sociotechnical factors associated with LED. Perception of cues in different environments facilitates successful LED, for which the deliberate review of past tasks within two hours of the error occurring and whilst remaining in the same or similar sociotechnical environment to that which the error occurred appears most effective. Identified ergonomic interventions offer potential mitigation for latent errors; particularly in simple everyday habitual tasks. It is thought safety critical organisations should look to engineer further resilience through the application of LED techniques that engage with system cues across the entire sociotechnical environment, rather than relying on consistent human performance.

Task Engagement and Attentional Resources

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.

Automation Reliability and Other Contextual Factors in Multi-UAV Operator Selection

Multi-unmanned air vehicle (UAV) operation requires a unique set of skills and high demand for new operators requires selection from populations without previous flight training. To support developing criteria for multi-UAV operator selection, the present study investigated the role of multiple individual difference factors in performance under different multi-UAV specific contexts. Specifically, we compared performance under fatigue using a high- and low-reliability automated aid. Accuracy on surveillance tasks, as well as reliance on automation were assessed. Video gaming expertise was associated with reduced stress and less reliance with a low-reliability automated aid. Distress was the most robust predictor of performance accuracy, but high distress was harmful only when reliability was low. Personality correlates of performance varied with both automation reliability and gender. Our findings suggest that multi-UAV operator selection should take into account the reliability of the automated systems.

A Meta-Analysis of Factors Influencing the Development of Trust in Automation: Implications for Understanding Autonomy in Future Systems

OBJECTIVE

We used meta-analysis to assess research concerning human trust in automation to understand the foundation upon which future autonomous systems can be built.

BACKGROUND

Trust is increasingly important in the growing need for synergistic human-machine teaming. Thus, we expand on our previous meta-analytic foundation in the field of human-robot interaction to include all of automation interaction.

METHOD

We used meta-analysis to assess trust in automation. Thirty studies provided 164 pairwise effect sizes, and 16 studies provided 63 correlational effect sizes.

RESULTS

The overall effect size of all factors on trust development was ḡ = +0.48, and the correlational effect was [Formula: see text]  = +0.34, each of which represented medium effects. Moderator effects were observed for the human-related (ḡ  = +0.49; [Formula: see text] = +0.16) and automation-related (ḡ = +0.53; [Formula: see text] = +0.41) factors. Moderator effects specific to environmental factors proved insufficient in number to calculate at this time.

CONCLUSION

Findings provide a quantitative representation of factors influencing the development of trust in automation as well as identify additional areas of needed empirical research.

APPLICATION

This work has important implications to the enhancement of current and future human-automation interaction, especially in high-risk or extreme performance environments.

Workers' Risk Tolerance and Occupational Injuries

This study explores the relationship between individuals' risk tolerance and occupational injuries. We analyze data from a national representative survey of U.S. workers that includes information about injuries, risk tolerance, cognitive and noncognitive attributes, and risky behaviors. We measure risk tolerance through questions regarding individuals' willingness to gamble on their lifetime income. We estimate zero-inflated count models to assess the role played by such measures on workers' recurrent injuries. We discuss some implications of our results for future research and occupational safety policies. Our results highlight the concurrent and changing role played by individual, work, and environmental factors in explaining recurrent incidents. They show that risk tolerance affects recurrent injuries, although not in the direction that proponents of the concept of proneness would expect. Our measure of risk aversion shows that individuals who are somewhat more risk tolerant have fewer recurrent injuries than those who are risk averse. But the estimated relationship is U-shaped, not monotonic and, therefore, not easy to predict. At the same time, we find that individuals' "revealed risk preferences"-specific risky behaviors-are related to higher injury probabilities. Demanding working conditions, measures of socioeconomic status, health, and safety problems experienced by workers during their youth remain among the most important factors explaining the phenomena of recurrent injuries. So our results contribute also to the important debate about the relationship between health and socioeconomic status.

Effects of chronotype and time of day on the vigilance decrement during simulated driving

The current study tested for the first time the effect of individual differences in circadian rhythmicity (chronotype) on both driving performance and its evolution along time on task. Morning-type and evening-type female participants were tested in morning (8 am) and evening (8 pm) sessions, in which we controlled for prior sleep duration and prior wake. Measures of body temperature, subjective activation and affect, reaction times (RT) in the Psychomotor Vigilance Task (PVT), behavioral performance (error position) and EEG alpha power during simulated driving were collected. The main result showed strong linear increments of mean and standard deviation of error position along time on task (vigilance decrement) when evening-type participants drove at their non-optimal time of day, that is, during the morning session. In contrast, driving performance in the morning-type group remained stable over time on task and was not affected by time of day. This finding can be due to differences in personality traits (e.g., conscientiousness, sensation seeking) and task appraisal associated to extreme chronotypes. The consideration of chronotype in vigilance and driving tasks can enhance safety and human performance by promoting work schedules and countermeasures to prevent failures in the accomplishment of tasks under non-optimal circadian conditions.

Predicting battlefield vigilance: a multivariate approach to assessment of attentional resources

Technological innovation increasingly requires operators in various applied settings to maintain vigilance for extended periods. However, standard psychometric tests typically predict less than 10% of performance variance. The present study (N = 462) aimed to apply the resource theory of sustained attention to construct a multivariate test battery for predicting battlefield vigilance. The battery included cognitive ability tests, a high-workload short vigilance task and subjective measures of stress response. Four versions of a 60- min simulated military battlefield monitoring task were constructed to represent different operational requirements. The test battery predicted 24-44% of criterion variance, depending on task version, suggesting that it may identify vigilant operators in military and other applied contexts. A multiple-groups path analysis showed that relationships between ability and vigilance were moderated by working memory demands. Findings are consistent with a diffuse theoretical concept of 'resources' in which performance energisation depends on multiple, loosely coupled processes.

The vigilance decrement in executive function is attenuated when individual chronotypes perform at their optimal time of day

Time of day modulates our cognitive functions, especially those related to executive control, such as the ability to inhibit inappropriate responses. However, the impact of individual differences in time of day preferences (i.e. morning vs. evening chronotype) had not been considered by most studies. It was also unclear whether the vigilance decrement (impaired performance with time on task) depends on both time of day and chronotype. In this study, morning-type and evening-type participants performed a task measuring vigilance and response inhibition (the Sustained Attention to Response Task, SART) in morning and evening sessions. The results showed that the vigilance decrement in inhibitory performance was accentuated at non-optimal as compared to optimal times of day. In the morning-type group, inhibition performance decreased linearly with time on task only in the evening session, whereas in the morning session it remained more accurate and stable over time. In contrast, inhibition performance in the evening-type group showed a linear vigilance decrement in the morning session, whereas in the evening session the vigilance decrement was attenuated, following a quadratic trend. Our findings imply that the negative effects of time on task in executive control can be prevented by scheduling cognitive tasks at the optimal time of day according to specific circadian profiles of individuals. Therefore, time of day and chronotype influences should be considered in research and clinical studies as well as real-word situations demanding executive control for response inhibition.

The role of calmness in a high-Go target detection task

Individual differences (e.g., extroversion) have been noted to influence performance on sustained attention tasks (Davies & Parasuraman, 1982). It has been proposed that the sustained attention to response task (SART) is a valid measure of lapses in attention and has been extensively used in attention studies (Manly, Robertson, Galloway, & Hawkins, 1999; Robertson, Manly, Andrade, Baddeley, & Yiend, 1997). In the current investigation we test whether SART is a measure of sustained attention versus a measure of motor control. Additionally, we tested how individual differences using an abridged version of the Big Five personality traits scale related to SART performance. Two-hundred and ninety-six university students completed a SART and the Big Five scale. The behavioral results revealed a negative correlation between errors of commission and response time which is indicative of a speed-accuracy trade-off. The individual difference results revealed that those who report themselves higher on the calmness trait (non-neurotic) make less errors of commission (inappropriate response) and have slower response times. However, mediation regression analysis revealed that the relationship between the calmness individual difference and commission errors may be mediated by response time. Collectively, the SART may be a better measure of response inhibition than sustained attention and SART performance can be influenced by individual differences which influence the speed-accuracy trade-off.

Psychometric properties of the Cognitive Failures Questionnaire

The Cognitive Failures Questionnaire (CFQ) is used in ergonomics research to measure behavioural problems associated with attentiveness and memory in everyday life. CFQ scores have been related to constructs such as accident proneness and outcomes such as human error and psychological strain. The two-year test-retest reliability of the CFQ is reported together with the findings of factor analyses of CFQ data from 535 respondents. Evidence for the predictive and criterion validity and internal reliability of the CFQ is provided. Psychological strain was measured concurrently with CFQ on both testing occasions, two years apart. The test-retest reliability of the summated CFQ score was found to be 0.71, while for the General Health Questionnaire (GHQ-12) strain measure it was 0.32.The relative variance stability was five times greater for the CFQ than the GHQ, indicating that scores on these questionnaires are not covariates. The use of the CFQ as a measure of cognitive control capacity is also discussed.

PRACTITIONER SUMMARY

Ergonomists have long been interested in human error and the role of high work demands due to poor equipment design and excessive workload. The CFQ measures attentiveness in daily life and is shown to have excellent psychometric properties that make it suitable for use in both laboratory and field studies as a trait measure of attentiveness in daily life.

The influence of camouflage, obstruction, familiarity and spatial ability on target identification from an unmanned ground vehicle

The purpose of this study was to examine the effects of environmental and cognitive factors on the identification of targets from an unmanned ground vehicle (UGV). This was accomplished by manipulating obstruction, camouflage and familiarity of objects in the environment, while also measuring spatial ability. The effects of these variables on target identification were studied by measuring performance of participants that observed pre-recorded video from a 1:35 scaled military operations in urban terrain facility. Analyses indicated that a combination of camouflage and obstruction caused the most detrimental effects on performance, and that there were differences in the recognition of familiar and unfamiliar targets. Further analysis indicated that these detrimental effects could only be overcome with a combination of target familiarity and spatial ability. The findings highlight the degree to which environmental factors hinder performance and the need for a multidimensional approach for improving performance under these conditions. Areas in need of future research are also discussed.

PRACTITIONER SUMMARY

Cognitive theory is applied to the problem of perception from UGVs. Results from an experimental study indicate that a combination of camouflage and obstruction caused the most detrimental effects on performance, with differences in the recognition of both familiar and unfamiliar targets. Familiarity and spatial ability interacted to predict the performance.

Accident proneness revisited: the role of psychological stress and cognitive failure

Understanding why accidents occur in the work place has a long and convoluted history. This paper adds to this corpus of research by investigating the relationship between an individual's level of cognitive failure, psychological stress, and work place accident occurrence. Retrospective analysis of accident-case individuals vs. control-match individuals on the General Health Questionnaire (GHQ) and Cognitive Failures Questionnaire (CFQ) was undertaken from amalgamated data of two Royal Navy databases. Individuals in the accident-case sub-sample had higher GHQ and CFQ scores when compared to matched-controls. Mediated regression analysis revealed high GHQ score predicted accidents but was transmitted through high CFQ scores. Individuals who are stressed are more likely to have an accident in the workplace because of a propensity for cognitive failures. A specific recommendation to reduce accident risk in the work-place is discussed.

Cognitive process modelling of controllers in en route air traffic control

In recent years, various efforts have been made in air traffic control (ATC) to maintain traffic safety and efficiency in the face of increasing air traffic demands. ATC is a complex process that depends to a large degree on human capabilities, and so understanding how controllers carry out their tasks is an important issue in the design and development of ATC systems. In particular, the human factor is considered to be a serious problem in ATC safety and has been identified as a causal factor in both major and minor incidents. There is, therefore, a need to analyse the mechanisms by which errors occur due to complex factors and to develop systems that can deal with these errors. From the cognitive process perspective, it is essential that system developers have an understanding of the more complex working processes that involve the cooperative work of multiple controllers. Distributed cognition is a methodological framework for analysing cognitive processes that span multiple actors mediated by technology. In this research, we attempt to analyse and model interactions that take place in en route ATC systems based on distributed cognition. We examine the functional problems in an ATC system from a human factors perspective, and conclude by identifying certain measures by which to address these problems. This research focuses on the analysis of air traffic controllers' tasks for en route ATC and modelling controllers' cognitive processes.

PRACTITIONER SUMMARY

This research focuses on an experimental study to gain a better understanding of controllers' cognitive processes in air traffic control. We conducted ethnographic observations and then analysed the data to develop a model of controllers' cognitive process. This analysis revealed that strategic routines are applicable to decision making.

Decisional style, mood and work communication: email diaries

To understand the use of technology to support interpersonal interaction, a theory of decisional style was applied to email use within the workplace. Previous research has used self-report and rating scales to address employee email behaviours, but this falls short of management's capability to monitor the actual behaviour. Thirty-nine employed individuals completed a five-day communication diary recording their actual behaviour upon receiving personal and work-related emails as well as the Melbourne Decision Making Questionnaire and the Depression Anxiety Stress Scales. It was found that vigilant individuals were more likely to use email in an efficient manner by deleting personal email and being less likely to open email later. Procrastinators, buckpassers and people experiencing high levels of negative affect were all more likely to delay dealing with email, which could be viewed as dealing with email in a less efficient manner. STATEMENT OF RELEVANCE: This work offers insights as to how people receive and process emails and is thus relevant to the development and implementation of collaborative technologies. Whilst other studies use individual's self-reports, this study uses a more accurate communication diary. Decisional style can predict the monitoring and response to electronic communication.

Cognitive-emotional dysfunction among noisy minds: predictions from individual differences in reaction time variability

Mental noise can be defined as less reliable information processing. Individuals with high levels of mental noise are thought to be disadvantaged in cognitive, emotional, and behavioural realms. The present five studies (total N=298) investigated such potential disadvantages among normally functioning college undergraduates. Mental noise was operationalised in terms of the reaction time coefficient of variation (RTCV), a measure of RT variability that corrects for average levels of mental speed. Individuals with higher RTCV exhibited less effective cognitive control (Studies 1 and 5), less controlled behaviour (Study 2), and were more prone to negative emotional experiences (Study 3) and depressive symptoms (Study 4). Study 5 extended these results and found that individuals higher (versus lower) in RTCV were more adversely affected by their attentional lapses in daily life. Results converge on the idea that mental noise is an important individual difference dimension with multiple adverse correlates and consequences.

Cumulative psychological strain and future strain in Naval personnel: is executive function the elephant in the room?

Psychological strain was measured in 592 Naval personnel at four phases using the General Health Questionnaire (GHQ-12). The GHQ-12 Likert score was summed to generate a measure of cumulative strain, which was best predicted by the Cognitive Failures Questionnaire (CFQ) score, effort-reward imbalance and a measure of organisational commitment. Point strain at phase IV was best predicted by CFQ score, whereas need for recovery was best predicted by over-commitment to work role. Susceptibility to strain, both cumulatively over 2 years and 12 months in the future appears to depend on a cognitive factor measured by the CFQ. This factor was more strongly associated with strain than with fatigue. Psychosocial stress exposure at work played a lesser role in predicting cumulative and future strain, possibly because these stressors were of an acute nature. The findings are discussed with reference to recent research on attention and anxiety and some of the practical implications are considered. STATEMENT OF RELEVANCE: There is renewed interest in intrinsic variables that predict adverse reactions to occupational stress. The paper presents evidence that self-reported cognitive failure is a vulnerability factor for future episodes of psychological strain. The paper strengthens the conclusions of a previous article and adds empirical support to recent research on the links between anxiety and attention.

Defining the drivers for accepting decision making automation in air traffic management

Air Traffic Management (ATM) operators are under increasing pressure to improve the efficiency of their operation to cater for forecasted increases in air traffic movements. One solution involves increasing the utilisation of automation within the ATM system. The success of this approach is contingent on Air Traffic Control Operators' (ATCOs) willingness to accept increased levels of automation. The main aim of the present research was to examine the drivers underpinning ATCOs' willingness to accept increased utilisation of automation within their role. Two fictitious scenarios involving the application of two new automated decision-making tools were created. The results of an online survey revealed traditional predictors of automation acceptance such as age, trust and job satisfaction explain between 4 and 7% of the variance. Furthermore, these predictors varied depending on the purpose in which the automation was to be employed. These results are discussed from an applied and theoretical perspective. STATEMENT OF RELEVANCE: Efficiency improvements in ATM are required to cater for forecasted increases in air traffic movements. One solution is to increase the utilisation of automation within Air Traffic Control. The present research examines the drivers underpinning air traffic controllers' willingness to accept increased levels of automation in their role.

Real-time performance modelling of a Sustained Attention to Response Task

Vigilance declines when exposed to highly predictable and uneventful tasks. Monotonous tasks provide little cognitive and motor stimulation and contribute to human errors. This paper aims to model and detect vigilance decline in real time through participants' reaction times during a monotonous task. A laboratory-based experiment adapting the Sustained Attention to Response Task (SART) is conducted to quantify the effect of monotony on overall performance. Relevant parameters are then used to build a model detecting hypovigilance throughout the experiment. The accuracy of different mathematical models is compared to detect in real time - minute by minute - the lapses in vigilance during the task. It is shown that monotonous tasks can lead to an average decline in performance of 45%. Furthermore, vigilance modelling enables the detection of vigilance decline through reaction times with an accuracy of 72% and a 29% false alarm rate. Bayesian models are identified as a better model to detect lapses in vigilance as compared with neural networks and generalised linear mixed models. This modelling could be used as a framework to detect vigilance decline of any human performing monotonous tasks. STATEMENT OF RELEVANCE: Existing research on monotony is largely entangled with endogenous factors such as sleep deprivation, fatigue and circadian rhythm. This paper uses a Bayesian model to assess the effects of a monotonous task on vigilance in real time. It is shown that the negative effects of monotony on the ability to sustain attention can be mathematically modelled and predicted in real time using surrogate measures, such as reaction times. This allows the modelling of vigilance fluctuations.

Functional Fidelity, Context-Matching, and Individual Differences in Performance

Conventional personality questionnaires are often only weak predictors of operational performance. A major problem is that personality effects are moderated by contextual factors which may be mismatched across laboratory and real-world studies. Context mismatch threatens the ‘functional fidelity’ of laboratory performance tasks; the extent to which the individual behaves as they would in the operational environment. Three research strategies for enhancing the functional fidelity of laboratory studies of individual differences are proposed. First, contexts relevant to specific personality traits may be developed in the laboratory. For example, socially threatening environments may be necessary to find meaningful effects of neuroticism. Second, traits linked to a specific performance context may be employed. The validity of traits for driver stress vulnerability supports this approach. Third, psychophysiological responses to simulations of the cognitive demands of the work environment may be used. Our recent work shows that stress and hemodynamic responses to short high-workload tasks predict longer-duration sustained performance.

A Multivariate Test Battery for Predicting Vigilance

It has proved difficult to predict individual differences in vigilance from standard psychometric tests. We report a study that explored the utility of a multivariate battery in predicting vigilance on a task requiring monitoring of a tactical display. A two-phase design was employed. Participants performed a short vigilance task (SVT) prior to the longer criterion monitoring task. We investigated the predictive ability of cognitive ability, personality, performance on the SVT, and stress responses to the SVT. Four versions of the criterion task were used, to test generalization of predictive validity. Key predictors of vigilance were found to include ability, SVT performance, and subjective task engagement and coping. Multiple regression analyses suggested that together these predictors explained about 30% of the variance in vigilance (with some differences for prediction of different task versions). Results are discussed in relation to the resource theory of vigilance, and the practical issues arising from selecting vigilant operators.

Job strain related to cognitive failure in naval personnel

The Naval Service Stress Study (2007-2012) is investigating job strain, its characteristics, causes and distribution in the Service. Data from phases I, II and III of the study (January 2007, June 2007 and January 2008) were analysed to determine the relationship between General Health questionnaire scores and a score on the Cognitive Failures Questionnaire (CFQ) completed at phase III. Of 791 personnel who completed questionnaires at all phases, 43.6% had no job strain at any phase, whereas 9.9% had strain on all three occasions ('chronic strain'). 27% had strain at one of the three phases and 19% had strain at two of the three phases. The particular phase at which job strain was experienced was not related to CFQ score at phase III, whereas the total strain experienced over the period was related. High strain over the year was the strongest predictor of high CFQ score. A 'strain dose' variable, which combined both the amount of strain exposure and the timing of the exposure, explained little additional variance in CFQ score. The findings might be interpreted to indicate that a high CFQ score is a vulnerability factor for adverse reactions to work stress. The hypothesis that recent job strain elevates CFQ score was not supported. STATEMENT OF RELEVANCE: Current models of occupational stress focus on psychosocial factors and much of the advice about stress management in organisations is centred on the identification and control of psychosocial risk factors. The present paper provides evidence that cognitive factors are also important and suggests that support for those with poor executive function should be part of stress management in complex environments.

Effects of 60 hours of total sleep deprivation on two methods of high-speed ship navigation

This study investigated how workload and performance in high-speed ship navigation was affected by sleep deprivation using methods based on either paper charts or electronic chart display and information systems (ECDIS). In two separate weeks, five navigators sailed 10 routes in high-fidelity simulators while undergoing progressive sleep deprivation for up to 60 h. Results showed that navigation performance was better using ECDIS, but was largely unaffected by sleep deprivation in both. There was significant interaction between speed, sleep deprivation and navigation method, indicating that navigators using ECDIS reduced their speed more while sleepy. Secondary task performance was reduced by sleep deprivation, but was equally affected in both conditions. Workload was higher in the ECDIS condition, as indicated by subjective ratings and heart rate variability. No significant differences in sleepiness were found, but electroencephalographic recordings indicated more frequent microsleep episodes in the ECDIS condition. This may be influenced by lower overall arousal while navigating with ECDIS.