Search

The sustained attention to response task (SART) has been used for over 20 years to assess participants’ response times and inability to withhold to No-Go stimuli (commission errors). While there is debate in the literature regarding what causes commissions errors in the SART, there is agreement the SART is subject to a speed-accuracy trade-off (SATO). Researchers have demonstrated that performance on the SART can be influenced by directive instructions to participants to prioritize either speed or accuracy during the task. In the present study, we investigated whether real-time performance feedback and whether feedback emphasis (emphasizing speed or accuracy) affected participants’ response times and accuracy. We found performance feedback per se had no impact on performance, but performance emphasis did affect performance, apparently shifting the SATO. This finding provides further evidence that the commission errors in the SART are not indicative of sustained attention or vigilance as those terms are commonly used in the literature, but more likely assess response strategy and motor control (or lack of motor control). These findings have implications for the psychological assessment literature, as well as applied areas where SART findings have been utilized such as shoot/no-shoot decision making.

Objective To explore vigilance task performance, cerebral blood flow velocity (CBFV), workload, and stress in a within-subjects, two-session experiment. Background Vigilance, or sustained attention, tasks are often characterized by a decline in operator performance and CBFV with time on task, and high workload and stress. Though performance is known to improve with practice, past research has not included measures of CBFV, stress, and workload in a within-subjects multi-session design, which may also provide insight into ongoing theoretical debate. Method Participants performed a vigilance task on two separate occasions. Performance, CBFV, workload, and self-reported stress were measured. Results Within each session, results were consistent with the vigilance profile found in prior research. Across sessions, performance improved but the time on task decrement remained. Mean CBFV and workload ratings did not differ between sessions, but participants reported significantly less distress, worry, and engagement after session two compared to one. Conclusion Though practice may not disrupt the standard vigilance profile, it may serve to improve overall performance and reduce stress. However, repeated exposure may have negative implications for engagement and mind-wandering. Application It is important to better understand the relationship between experience, performance, physiological response, and self-reported stress and workload in vigilance because real-world environments often require operators to do the same task over many occasions. While performance improvement and reduced distress is an encouraging result, the decline in engagement requires further research. Results across sessions fail to provide support to the mind-wandering theory of vigilance.

Vigilance, or the ability to sustain attention for extended periods of time, has been of interest to the human factors and ergonomics community for 70 years. During this time, several theories have...

Objective: To investigate whether depleting self-control prior to vigilance results in a steeper vigilance decrement. Background: The resource-control theory of vigilance asserts that an inherent bias toward self-generated mind-wandering draws attentional resources away from the primary task. This study seeks to test whether depleting self-control, the potential mechanism of self-generated mind-wandering, results in poorer vigilance performance. Method: This study featured a between-subjects design where participants either completed a typing task that depleted self-control resources or a standard typing task that did not require self-control before performing a vigilance task. In the self-control depletion condition, participants typed a passage while omitting any “e” and “space” keys. In the standard typing task, participants typed the same passage without skipping any keys. Following both typing tasks, participants in both conditions completed an identical 12-min vigilance task. Results: Results demonstrated decreased accuracy and increased reaction times over time for both groups. Depleting self-control did not result in significant differences in accuracy, reaction time, nor a steeper vigilance decrement. Conclusion: These results provide evidence against resource-control theory and self-control as an explanation for vigilance, and provide further support for cognitive resource theory as the predominant explanation for vigilance impairments. Application: It is still unclear exactly what constitutes a “resource.” A better understanding of the nature of these resources can help researchers and practitioners identify how they can be replenished, which could enhance human performance in situations requiring vigilance such as baggage screening.

The inability to maintain signal detection performance with time on task, or vigilance decrement, is widely studied in people. Despite suggestions that limitations in sustained attention may be a fundamental characteristic of animal cognition, there has been limited research on the vigilance decrement in other animals. We conducted two experiments to explore vigilance in jumping spiders. Our first experiment established that the vigilance decrement, decline in signal detections with time on task, occurs in these spiders in laboratory settings. Our second experiment tested whether this phenomenon was simply the result of habituation of sensory receptors by employing two dishabituation manipulations. Neither dishabituation manipulation appeared to have an effect. Thus, the vigilance decrement in spiders appears to be due to something more than simply peripheral sensory habituation. We suggest that limitations in sustained attention may be a widespread phenomenon among animals that needs addressing when theorising about the vigilance decrement.

The Sustained Attention to Response Task (SART) has been widely used in psychological literature as a measure of vigilance (the ability to sustain attention over a prolonged period of time). This task uses a Go/No-Go paradigm and requires the participants to repetitively respond to the stimuli as quickly and as accurately as possible. Previous literature indicates that performance in SART is subjected to a "speed-accuracy trade-off" (SATO) resulting from strategy choices and from the failures of controlling motor reflexes. In this study, 36 participants (n = 36) performed a series of four SARTs. The results support the perspective of strategy choice in SART and suggest that within-subjects SATO in SART should also be acknowledged in attempting to explain SART performance. The implications of the speed-accuracy trade-off should be fully understood when the SART is being used as a measure or tool.

Objective: We examined the impact task interruptions of differing qualitative and quantitative load have on visuospatial vigilance sensitivity. Background: The vigilance decrement and attempts to develop countermeasures to the decrement is one of the most important human factors issues. There is an ongoing debate between those who interpret the increase in the rate of failures to detect signals over time as being due to objective task monotony or task underload and those who interpret this increased failure proneness as being predominately due to cognitive-resource depletion and task overload. Method: Participants were assigned at random to one of six interruptions: Participants were given a complete rest (rest); participants completed a 1-back verbal working-memory (WM) task, a 3-back verbal WM task, a 1-back spatial WM task, or a 3-back spatial WM task; or participants performed the primary vigilance task (continuous). Results: Postinterruption performance was best for rest and worst for continuous. A resource theory perspective led us to make two possible predictions of relative interruption effect orders of the six conditions out of 720 possible orderings. We found one of the two orders. Conclusion: Overall, the vigilance sensitivity decrement appears to be due to the recurring use of particular cognitive resources, and resource theorists should explore this more extensively in the future. Application: Countermeasures for the vigilance decrement should be based on clear cognitive-resource considerations. Rest is the best countermeasure. Intervening tasks should be chosen that minimize resource-demand overlap with the vigilance task.

In jumping spiders (Salticidae), the vigilance decrement, or decrease in response to a repeated visual stimulus over time, directly parallels that found in humans. Explanations for the vigilance decrement in the human literature are heavily mentalistic and central nervous system (CNS) based, whereas response decrements in invertebrates are typically thought of as habituation at the sensory periphery. Here we explored whether the salticid vigilance decrement could be CNS modulated by using caffeine, which is a well-known CNS stimulant for both vertebrates and invertebrates. We used paired tests in which Trite planiceps Simon spiders were randomly given a drop of either caffeinated water or distilled water and were then shown dot stimuli presented on monitors. We measured both general "walking," or activity, as a control for physical fatigue, and optomotor responses to the stimuli. We found that the vigilance decrement was significantly shallower (i.e., spiders were more responsive for longer) when spiders were administered caffeine compared with water; furthermore, these spiders were also generally more active throughout the testing period and thus were not physically impaired. Our results suggest that, in at least some invertebrates, CNS modulation of the vigilance decrement is likely. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Objective: Two verbal tasks were utilized in a dual-task paradigm to explore performance theories and prior dual-tasking results. Background: Both the decline in vigilance performance over time, or vigilance decrement, and limited dual-tasking ability may be explained by limited mental resources. Resource theorists would recommend removing task demands to avoid cognitive overload, while mindlessness theorists may recommend adding engaging task demands to prevent boredom. Prior research demonstrated interference between a verbal free recall and semantic vigilance task, but exploring tasks with greater ecological validity is necessary. Method: A narrative memory task and semantic vigilance task were performed individually and simultaneously. Relative performance impairments were compared to a previous dual-task pairing. Results: The semantic vigilance task caused performance degradation to the narrative memory task and vice versa. A vigilance decrement was not observed, and the interference was to a lesser extent than when the semantic vigilance task was paired with a free recall task. Conclusion: Resource theory was supported, though passive learning effects during a semantic vigilance task with novel stimuli may prevent a vigilance decrement. The interference was less than that of a previous similar dual-task pairing, but even tasks as routine as listening to a conversation or story can impair other task performance. Application: A better understanding of resource theory and dual-task performance outcomes can help inform feasible task loads and improve efficiency and safety of operators in high-risk and other professions.

This study explores the impact of post-earthquake images inserted in a vigilance task, in terms of performance, self-reports of task-focus, and cerebral activity using functional near-infrared spectroscopy (fNIRS). Vigilance tasks present a sequence of stimuli in which only a few are pre-designated critical or target stimuli requiring an overt response from the participant. Seventy-one residents participated (51 women, 20 men) by taking part in a vigilance task with task-irrelevant images inserted in the sequence. There were three conditions consisting positive (emotive inducing), negative (emotive inducing), and control (devoid of meaning) images embedded in the vigilance task to assess possible impacts on vigilance performance. The images were obtained through crowdsourcing and represented parts of the city 3-4 years post-earthquake. Task performance was assessed with signal detection theory metrics of sensitivity A' and bias β''. This enables the separation of an individual's ability to accurately discriminate critical signals from non-critical stimuli (sensitivity) and shifts in their willingness to respond to any stimuli whether critical or not (bias). Individuals viewing the positive images, relating to progress, rebuild, or aesthetic aspects within the city, had a more conservative response bias (they responded less to both rare critical and distractor stimuli) than those in the other conditions. These individuals also reported lower task-focus, as would be expected. However, contrary to expectations, indicators of cerebral activity (fNIRS) did not differ significantly between the experimental groups. These results, when combined, suggest that mind wandering events may be being generated when exposed to positive post-earthquake images.

Many everyday tasks, such as driving and reading technical reports, require sustained attention. These tasks may deplete attentional resources and/or lead to mind wandering, boredom and fatigue – cognitive states that result in impaired performance. Numerous competing theories exist to explain these performance decrements. In this panel, we will examine perspectives from both the fatigue and vigilance literatures, identifying points of common ground and differences in an attempt to further understand the underpinnings of performance decrements in tasks that require sustained attention. Experts in the interrelated yet frequently viewed as disparate areas of fatigue and vigilance are brought together to forge new theoretical ground.

The inability to maintain signal detection performance with time on task, or vigilance decrement, is widely studied in people because of its profound implications on attention-demanding tasks over sustained periods of time (e.g., air-traffic control). According to the resource depletion (overload) theory, a faster decrement is expected in tasks that are cognitively demanding or overstimulating, while the underload theory predicts steeper decrements in tasks that provide too little cognitive load, or understimulation. Using Trite planiceps, a jumping spider which is an active visual hunter, we investigated vigilance decrement to repetitive visual stimuli. Spiders were tethered in front of two stimulus presentation monitors and were given a polystyrene ball to hold. Movement of this ball indicates an attempt to turn towards a visual stimulus presented to a pair of laterally facing (anterior lateral) eyes for closer investigation with high acuity forward-facing (anterior median) eyes. Vigilance decrement is easily measured, as moving visual stimuli trigger clear optokinetic responses. We manipulated task difficulty by varying the contrast of the stimulus and the degree of ‘noise’ displayed on the screen over which the stimulus moved, thus affecting the signal:noise ratio. Additionally, we manipulated motivation by paired testing of hungry and sated spiders. All factors affected the vigilance decrement, but the key variable affecting decrement was stimulus contrast. Spiders exhibited a steeper decrement in the harder tasks, aligning with the resource depletion theory.

This study was designed to validate a short-duration sustained visual search task for the assessment of sustained attention in process control environments. The task consists of 10 short dynamic scenarios, which require participants (N = 121) to monitor simulated operating power transmission interfaces, and identify system faults. A vigilance decrement was demonstrated throughout the sustained visual search task, as evident in increased response latencies and decreased accuracy over time. Further, changes in response latency throughout the sustained visual search task were positively associated with changes in response latency during a 30-min, low signal probability task, a 45-min low signal probability task, and a 45-min high signal probability task. The findings indicate that the sustained visual search task may be a valid alternative to a longer-duration process control task for experimental studies, and is likely to be of value for assessments of the capacity for sustained attention of operators in process control environments.

The present study was designed to explore the relationship between self-reported dissociative experiences and performance in vigilance tasks requiring a concurrent working memory load. Four hundred and ninety four students performed a vigilance task while simultaneously maintaining verbal working memory load or performing an equivalent control task. Dissociation was assessed with the Dissociative Experience Scale. There was a negative relationship between dissociation and perceptual sensitivity on the vigilance task. In addition, reaction times increased more over time for those high in dissociation when there was no concurrent memory load, compared to when there was a concurrent memory load. While the overall effect was weak, findings may support theories indicating a relationship between dissociation and dual-task performance.

Conscious appraisals of stress, or stress states, are an important aspect of human performance. This article presents evidence supporting the validity and measurement characteristics of a short multidimensional self-report measure of stress state, the Short Stress State Questionnaire (SSSQ; Helton, 2004 ). The SSSQ measures task engagement, distress, and worry. A confirmatory factor analysis of the SSSQ using data pooled from multiple samples suggests the SSSQ does have a three factor structure and post-task changes are not due to changes in factor structure, but to mean level changes (state changes). In addition, the SSSQ demonstrates sensitivity to task stressors in line with hypotheses. Different task conditions elicited unique patterns of stress state on the three factors of the SSSQ in line with prior predictions. The 24-item SSSQ is a valid measure of stress state which may be useful to researchers interested in conscious appraisals of task-related stress.

Sixty-one participants performed a sustained attention task in which they were required to respond to a critical signal requiring feature discrimination. Three separate groups performed the task with different global display configurations. The local feature elements (directional arrow shapes) were displayed on either a circle, a circle broken apart or a reconnected figure. For two of the groups, the entire display consisted of a clear global shape (circle and reconnected), and for one of the groups, the display had no discernible global element (broken circle) despite the critical signal being the same for all the groups. Analyses of hit rate and A' scores indicated that the broken circle group had impaired performance compared to the global figure groups. A configural superiority effect was found in which performance was improved by having a global shape property to the entire display. These results provide a behavioural base for further research utilizing measures of cerebral activation, as cerebral activity during vigilance tasks may be dependent on both task difficulty and hierarchical aspects of the display. The configurable or hierarchical aspects of vigilance displays may be critical in understanding sustained attention performance and its hemispheric lateralization.

A criticism of laboratory vigilance or sustained attention research is the employment of static monotonous tasks with repetitive targets as opposed to the use of dynamic tasks with novel target stimuli. Unfortunately dynamic tasks employing novel stimuli may result in the mixture of two cognitive processes: active sustained attention search and passive perceptual learning. Moreover, the relative engagement of these two processes may depend on individual differences. In the present study, we examined this by having participants perform a dynamic auditory vigilance task with rare novel targets. In addition, some participants performed this task while also performing a secondary motor tracking task, a dual-task scenario. In the dual-task scenario, participants who failed to accurately detect the first target stimuli showed improvements in their tracking performance with time-on-task, suggesting reserves of attention. This improvement in tracking performance was not evident for those who accurately detected the first target stimuli, as their attention was likely actively engaged (searching). In addition, participants in the dual-task scenario who accurately detected the first target stimuli reported high workload and increased post-task tense arousal, results characteristic of participants performing static vigilance tasks. These results indicate the possibility that in a dynamic vigilance task with novel target stimuli participants may diverge in how they approach the task. Some participants will actively monitor the display for targets (search), whereas others will passively learn the target stimuli. Thus, these tasks may pose significant challenges to researchers who wish to examine vigilance in isolation from perceptual learning.

We examined the impact task interruptions have on visuospatial vigilance in two experiments. In the first experiment participants were randomly assigned to one of three interruptions: participants were given a complete rest (rest), participants completed an alphanumeric vigilance task (letter), or participants performed the primary vigilance task (continuous). In the second experiment participants were randomly assigned to one of the conditions from the first experiment or to two further conditions, in which participants (spatial memory) performed a spatial match to sample task, or participants (verbal memory) performed a letter match to sample task. Vigilance performance post-interruption was best for rest, worst for continuous, and varied for the other interruption tasks. Overall, the results suggest the vigilance decrement is due to the repeated use of particular executive resources, but there may, in addition be domain specific interference when the primary task and activities during a break make use of the same resources.

Performance on the sustained attention to response task (SART) is often characterized by a speed-accuracy trade-off, and SART performance may be influenced by strategic factors (Head and Helton Conscious Cogn 22: 913-919, 2013). Previous research indicates a significant difference between reliable and unreliable warning cues on response times and errors (commission and omission), suggesting that SART tasks are influenced by strategic factors (Helton et al. Conscious Cogn 20: 1732-1737, 2011; Exp Brain Res 209: 401-407, 2011). With regards to warning stimuli, we chose to use cute images (exhibiting infantile features) during a SART, as previous literature indicates cute images cause participants to engage attention. If viewing cute things makes the viewer exert more attention than normal, then exposure to cute stimuli during the SART should improve performance if SART performance is a measure of perceptual coupling. Reliable warning cues were shown to reduce both response time and errors of commission, and increase errors of omission, relative to unreliable warning cues. Cuteness of the warning stimuli, however, had no significant effect on SART performance. These results suggest the importance of strategic factors in SART performance, not increased attention, and add to the growing literature which suggests the SART is not a good measure of sustained attention, vigilance or perceptual coupling.

We conducted two studies using a modified sustained attention to response task (SART) to investigate the developmental process of SART performance and the role of cognitive load on performance when the speed-accuracy trade-off is controlled experimentally. In study 1, 23 participants completed the modified SART (target stimuli location was not predictable) and a subjective thought content questionnaire 4 times over the span of 4 weeks. As predicted, the influence of speed-accuracy trade-off was significantly mitigated on the modified SART by having target stimuli occur in unpredictable locations. In study 2, 21 of the 23 participants completed an abridged version of the modified SART with a verbal free-recall memory task. Participants performed significantly worse when completing the verbal memory task and SART concurrently. Overall, the results support a resource theory perspective with concern to errors being a result of limited mental resources and not simply mindlessness per se.

In the present study we explored the impact of task-irrelevant emotive picture stimuli on visuo-spatial vigilance. Ninety-five participants completed the experiment in which task-irrelevant emotive picture stimuli were embedded in the vigilance task. Four experimental groups were tested by combining two levels of picture valence, positive versus negative, and two levels of picture arousal, arousing versus non-arousing, for the picture stimuli. The task was organized so that baseline performance, the initial impact of the images, and any continual carry-over effects of the images on performance could be measured. In addition to performance on the task, subjective state was measured using a self-report questionnaire designed to examine energetic and tense arousal as well as task-related and task-unrelated thoughts. The performance decrement of the groups exposed to the arousing picture stimuli was attenuated in comparison to those exposed to the non-arousing stimuli. Further the relationship between self-reported energetic arousal and performance differed for the arousing and non-arousing picture groups. Post-task energetic arousal significantly predicted the performance decrement for the arousing picture group, but not for the non-arousing picture group. These results provide support for the perspective that the arousal quality of picture stimuli matters more for performance than valence, and that arousing pictures while possibly disruptive when presented concurrently with the vigilance task may result in improved performance later due to an increase in energetic arousal.

Dogs have attracted the attention of biomimetic roboticists, for example, Sony’s Aibo. Properly designed robots may be able to elicit similar perceptions as dogs. It is important then to analyze the attitudes that people have towards dogs, in particular salient features like breed-membership. In the present paper we developed an electronic questionnaire to assess the existing mental models and categorizations of dog breeds. Subjects were asked to rate representatives of 48 different dog breeds with a 7-point Likert Scale for specific behavioral traits. Based on exploratory data analysis techniques, we found four clusters of breeds: Cluster 1 (Higher Drive, Useful, and Nice), Cluster 2 (Higher Drive, Useful, and not so Nice), Cluster 3 (Higher Drive, not so Useful, and not so Nice) and Cluster 4 (Lower Drive, not so Useful, and Nice). Implications for quadropedal robot design based on pertinent existing perceptions of dog breeds and their traits are discussed.

As text-based communication increases in the civilian and military workplace (Finomore, Popik, Castle, & Dallman, 2010), so does the potential to encounter text-speak. It has been proposed that processing text-speak (I wll tlk 2 u l8tr, I will talk to you later) comes at a cognitive cost (Head, Helton, Russell, & Neumann, 2012). To the authors’ knowledge, there have been no studies investigating the potential physiological cost of processing text-speak. In the current study we investigate the cognitive cost of processing text-speak by measuring performance on a dual-task while also measuring cerebral oxygenation in the prefrontal cortex. Sixty-four university students completed a dualtask which included a conscious priming task and a vigilance task. They also completed a text-speak questionnaire (Head, Helton, Russell, Neumann, & Shears, 2011). The behavioral results failed to show any significant difference in performance between text-speak and correctly spelled text. However, the physiological measurements revealed that the right prefrontal cortex has significantly greater activation when text-speak is shown, thus suggesting a RH compensatory effect. A significant correlation between the text-speak questionnaire and right-hemisphere activation suggests that the right-hemisphere contains the cognitive tools for overriding potential difficulties in processing textspeak.

The current investigation was conducted to elucidate whether errors of commission in the Sustained Attention to Response Task (SART) are indicators of perceptual or motor decoupling. Twenty-eight participants completed SARTs with motor and perceptual aspects of the task manipulated. The participants completed four different SART blocks whereby stimuli location uncertainty and stimuli acquisition were manipulated. In previous studies of more traditional sustained attention tasks stimuli location uncertainty reduces sustained attention performance. In the case of the SART the motor manipulation (stimuli acquisition), but not the perceptual manipulation (stimuli location uncertainty) significantly reduced commission errors. The results suggest that the majority of SART commission errors are likely to be indicators of motor decoupling not necessarily perceptual decoupling.

Despite a long history of vigilance research, the role of global and local feature discrimination in vigilance tasks has been relatively neglected. In this experiment participants performed a sustained attention task requiring either global or local shape stimuli discrimination. Reaction time to local feature discriminations was characterized by a quadratic trend over time-on-task with performance levels returning to initial levels late in the task. This trend did not occur in the global shape discrimination task. Functional near-infrared spectroscopy (fNIRS) was utilized in this study as an index of cerebral activation. In both tasks there was increased right hemisphere relative to left hemisphere oxygenation and right hemisphere oxygenation increased with time-on-task. Left hemisphere oxygenation, however, decreased slightly in the global task, but increased significantly in the local task as task duration increased. Indeed, total oxygenation, averaging both right and left, increased more with time-on-task in the local discrimination task. Both the performance and physiological results of this study indicate increased utilization of bilateral cerebral resources with time-on-task in the local, but not the global discrimination vigil.

We conducted two experiments using naturalistic scene stimuli to test the resource theory and mindlessness theory of sustained attention. In experiment 1, 28 participants completed a traditional formatted vigilance task consisting of non-repeating forest or urban picture stimuli as target stimuli. Participants filled out pre- and post-task assessments of arousal and conscious thoughts. There was still a vigilance decrement, despite non-repetitive, natural target stimuli. Participants found the task demanding and were actively engaged in the task. In experiment 2, 25 participants completed a Sustained Attention to Response Task (SART) using the stimuli from experiment 1. Participants performed significantly worse on this SART than either brain injury patients or controls performing equivalent numeric stimuli SARTs have in previous studies. Participants thought the task was demanding and they were actively engaged with the task. Overall, the results of both studies support a resource theory of sustained attention lapses, not a mindlessness theory.

Prior investigations have shown measurable performance impairments on continuous physical performance tasks when preceded by a cognitively fatiguing task. However, the effect of cognitive fatigue on bodyweight resistance training exercise task performance is unknown. In the current investigation 18 amateur athletes completed a full body exercise task preceded by either a cognitive fatiguing or control intervention. In a randomized repeated measure design, each participant completed the same exercise task preceded by a 52 minute cognitively fatiguing intervention (vigilance) or control intervention (video). Data collection sessions were separated by 1 week. Participants rated the fatigue intervention as being significantly more mentally demanding than the control intervention (p < .001). Additionally, participants self-reported significantly greater energetic arousal for cognitively fatiguing task (p = .02). Cognitive fatigue did not significantly impact number of repetitions completed during the exercise task (p = .77); however, when cognitively fatigued, participants had decreased percent time-on-task (57%) relative to the no fatigue condition (60%) (p = .04). RPE significantly changed over time (p < .001), but failed to show significant differences between the cognitive fatigue intervention and control intervention (p > .05). There was no statistical difference for heart rate or metabolic expenditure as a function of fatigue intervention during exercise. Cognitively fatigued athletes have decreased time-on-task in bodyweight resistance training exercise tasks.

Preliminary results from an on-going experiment exploring the localisation accuracy of a binaurally processed source displayed via a bone conduction headset are described. These results appear to point to decreased localisation accuracy in the horizontal plane when the vertical component is introduced. There also appears to be a significant compression in the area directly in front of the observer ± 15° in elevation from 0°. This suggests that participants tended to localise stimuli presented at elevations greater than and less than ± 30° within a 30° ‘window’ extending 15° vertically either above or below the horizontal plane defined by the 0° azimuth. The results gathered until now suggest that binaural spatialisation over a bone conduction headset can also reproduce the perception of an elevated source to an acceptable degree of accuracy.

This study examined the incidence of attention lapses and microsleeps under contrasting levels of task complexity during three tasks: PVT, 2-D tracking and a dual task combining the two. More attention lapses per participant (median 15vs. 3; range 1-74vs. 0-76, p=0.001), with the greatest increase with time spent-on-task (p=0.002), were evident on the more cognitively-demanding dual task than on the PVT. Conversely, fewer microsleeps (median 0vs. 0; range 0-1vs. 0-18, p=0.022) occurred during the more complex task compared to the tracking task. An increase in microsleep rate with time spent-on-task (p=0.035) was evident during the tracking task but not the dual task. These results indicate that the higher cognitive load, associated with an increase in task complexity, increased the likelihood of attention lapses, while a reduction in task complexity increased the likelihood of microsleeps.

The present study was designed to explore the performance costs of negative emotional stimuli in a vigilance task. Forty participants (20 women) performed a vigilance task in two conditions: one with task-irrelevant negative-arousing pictures and one with task-irrelevant neutral pictures. In addition to performance, we measured subjective state (energetic arousal, tense arousal, task-related and task-unrelated thoughts) and frontal cerebral activity with near infrared spectroscopy. Overall performance in the negative picture condition was lower than in the neutral picture condition and the negative picture condition had elevated levels of energetic arousal, tense arousal and task-related thoughts. Moreover, there was a significant relationship between the impact of the negative pictures on tense arousal and task-related thoughts and the impact of the negative pictures on performance (in comparison to the neutral picture stimuli task). These results provide support for indirect cost models of negative emotional stimuli on target detection performance.

Researchers have suggested a link between right-hemisphere dysfunction and reported attention-deficit/hyperactivity disorder (ADHD) symptoms. In this experiment non-clinical participants completed the Adult ADHD Self-report Scale (ASRS) and performed a vigilance task requiring either global or local letter target discriminations. Global target discriminations have shown right hemisphere dominance and local target discriminations have shown left hemisphere dominance in brain imaging studies. While the global-local discrimination did not affect the results, the ASRS did significantly predict the decline of detections over time on task, e.g. the vigilance decrement. Thus, the ASRS may be useful in non-clinical populations as a predictor for vigilance performance. Language: en

The present study was designed to explore the relationship between self-reported dissociative experiences and performance in tasks eliciting right-hemisphere processing load. Thirty-four participants (10 men and 24 women) performed a vigilance task in two conditions: with task-irrelevant negative-arousing pictures and task-irrelevant neutral pictures. Dissociation was assessed with the Dissociative Experience Scale. Consistent with theories positing right-hemisphere deregulation in high non-clinical dissociators, dissociative experiences correlated with greater vigilance decrement only in the negative picture condition. As both the vigilance task and negative picture processing are right lateralized, this result provides support for a right-hemisphere dysfunction in high dissociators, at least in negative conditions.

In this study, we examined the impact of concurrent verbal and spatial working memory demands on performance on an alpha-numeric successive target detection task. Seven hundred and forty-five participants performed a target detection task while simultaneously performing either a spatial or a verbal working memory task or they performed matched no-memory control tasks. The vigilance decrement, both an increase in target detection response times and a decrease in perceptual sensitivity A' to target stimuli over time, was exacerbated by concurrent working memory load. The spatial and verbal working memory loads both impacted vigilance performance suggesting utilization of common executive resources. Overall, these results support the view that the vigilance decrement results from high cognitive resource demands (e.g., hard work), not from cognitive under-load (e.g., boredom or mindlessness).

Animal behavioral flexibility is facilitated by the ability of animals to acquire expertise. For motor skills, expertise development is obvious; however, for perceptual and cognitive skills it is hidden from view. The study of covert skills in people is facilitated by the ability of people to verbally report what they are doing. Verbal reports are not an option when studying other animals. Nevertheless, systemic changes may be detectable by changes in performance variability. An increase in performance variability occurs during a period of self-reported skill phase transition in people in which more than 1 strategy is used in an intermixed fashion. For 2 perceptual categorization tasks in dogs (Canis lupus familiaris), 1 visual and 1 olfactory, running measures of performance variability reveal an increase in performance variability during training similar to the one seen during reported phase transitions in people. The use of running estimates of performance variability may be a new tool for detecting th...

Objectives: The present study was designed to explore whether target detection in a vigilance task is influenced by task-irrelevant negative emotional and neutral picture stimuli and to test predictions derived from the boredom-mindlessness versus resource depletion accounts of vigilance performance.Background: Previous research indicates that emotional stimuli can capture spatial attention. Research on the effect of negative emotional and neutral visual stimuli on temporal aspects of attention has not, however, been researched in detail.Method: For this study, 51 participants (15 men and 36 women) were assigned at random to one of three vigilance conditions: a visual vigil with task-irrelevant negative-arousing pictures, a visual vigil with task-irrelevant neutral pictures, or a no-picture visual vigil control. Vigilance performance was assessed in all conditions.Results: Overall performance efficiency was negatively influenced by the negative-arousing pictures and was interpreted to favor resource depletion to boredom-mindlessness accounts of vigilance performance.Conclusion: Task-unrelated negative emotional stimuli appear to impair absolute levels of target detections in a vigilance task.Application: In monitoring settings where negative emotional stimuli are present, the intrusion of negative emotional stimuli should be mitigated via alterations in the system design, or if this is implausible, the monitors may need additional stress coping and emotional resilience training.

We conducted two experiments using search asymmetry to test two theories of sustained attention lapses currently debated in the literature: the mindlessness theory and the resource theory. In the first experiment, participants performed a feature present and a feature absent sustained attention to response task (SART). The mindlessness theory predicts more commission errors in a feature present SART than a feature absent SART, while resource theory predicts the reverse, i.e. more commission errors in a feature absent SART than feature present SART. The latter occurred. In the second study, participants performed a naturalistic scene vigilance task with targets more analogous to a feature present search or more analogous to a feature absent search. The vigilance decrement occurred, with an increase in reaction time to targets over the course of the vigil. The decrement was more pronounced with the targets more analogous to a feature absent search. Overall, the results of both studies support a resource theory of sustained attention lapses, not the mindlessness theory.

Helton (2005) proposed that ergonomics professionals share an interest in the study of working dogs. In this paper, this proposal is further explored in regards to dogs as perceptual workers analogous to human perceptual workers. First, current performance estimates of expert dogs (signal detection A') are examined for wide variety of occupational domains from cancer to explosives detection. When tested in controlled conditions, dogs are competent workers, with A's ranging from .89 to 1.0. Second, models of human performance (perceptual work) may apply with some modification to working dogs. A case in point is Wickens' (2003) Attention-Situational Awareness (ASA) model, which is examined in the context of canine work. The A-SA model appears to be equally applicable to canine perceptual workers and human workers.

This article presents a study investigating the relationships between caffeine consumption, cognitive slips-failures, sleep and a short multidimensional self-report measure of daily stress state, the Short Stress State Questionnaire - Daily (SSSQ-D; Helton, Fields, & Thoreson, 2005). Thirteen participants filled out the SSSQ-D twice daily for approximately 14 days, once in the morning and once at night. They also reported daily cognitive slips-failures, caffeine consumption, and their sleep was recorded using actigraphs. Daily Distress and Worry correlated significantly with cognitive slips and sleep duration between-subjects. Until more is known, human operators should get the recommended 7–8hrs of sleep.

Remote navigation, popular in computer games and prevalent in areas such as clinical medicine and teleoperations of robots and drones, uses human-computer interfaces for control. Usability studies of remote navigation interfaces require good metrics for evaluating interfaces, assessing users' capabilities, and determining the difficulty of the navigational task. We studied the time proficient users took to navigate virtual hovercrafts through virtual hallways with corners of various widths and discovered that the time to negotiate corners is inversely proportional to corner width. We derive and evaluate two models for the index of difficulty for negotiating corners. Both models fit the data well, with r2 greater than 0.85 for the mean time to negotiate corners verses corner width.

Transcranial Doppler sonography (TCD) and transcranial cerebral oximetry (TCCO) measures of cerebral blood flow velocity and oxygenation levels were collected during an abbreviated 12-min vigilance task. Both the TCD and TCCO measures showed higher levels of cerebral vascular activity in the right than in the left cerebral hemisphere; the cerebral laterality of vigilance occurs in an abbreviated task. Although there was a significant decline in performance over time, there was no significant change in the physiological measures over time during the abbreviated vigil. This latter finding does not match the physiological changes detected in long-duration vigils.

The motor control of novice participants is often cognitively demanding and susceptible to interference by other tasks. As people develop expertise, their motor control becomes less susceptible to interference from other tasks. Researchers propose a transition in human motor skill from active control to automaticity. This progression may also be the case with nonhuman animals. Differences in performance characteristics between expert, advanced, intermediate, and novice dogs competing in the sport of agility were investigated. There were statistically significant differences between dogs of varying competitive levels in speed, motor control, and signal detections suggestive of increasing motor control automaticity in highly skilled, or expert, dogs. The largest sequential motor control difference was between novice and intermediate dogs, d = .96, whereas the largest sequential signal detection difference was between advanced and expert dogs, d = .90. These findings have two significant implications for expertise researchers: first, the observed similarities between dogs and humans may enable dogs to be used as expert models; and second, expertise science and methods may be profitably employed in the future to create more proficient canine workers.

The impact of anxiety-provoking stimuli on the Sustained Attention to Response Task (SART; Robertson, Manly, Andrade, Baddeley, & Yiend, 1997), and response inhibition more generally, is currently unclear. Participants completed four SARTs embedded with picture stimuli of two levels of emotion (negative or neutral) and two levels of task-relevance (predictive or non-predictive of imminent No-Go stimuli). Negative pictures had a small but detectable adverse effect on performance regardless of their task-relevance. Overall, response times and rates of commission errors were more dependent upon the predictive value (relevance) of the pictures than their attention-capturing nature (i.e., negative valence). The findings raise doubt over whether anxiety improves response inhibition, and also lend support to a response strategy perspective of SART performance, as opposed to a mindlessness or mind-wandering explanation.

Forty-five participants performed a vigilance task during which they were required to respond to a critical signal at a local feature level, while the global display was altered between groups (either a circle, a circle broken apart and reversed, or a reconnected figure). The shape in two of the groups formed a configurative whole (the circle and reconnected conditions), while the remaining shape had no complete global element (broken circle). Performance matched the results found in the previous experiments using this stimulus set, where a configural superiority effect was found to influence accuracy over time. Physiological data, measured using functional near-infrared spectroscopy, revealed elevated activation in the right pre-frontal cortex compared to the left pre-frontal cortex during the task. Additionally, bilateral activation was found in the conditions that formed configurative wholes, while hemispheric differences over time were found in the condition that did not. These findings suggest that configural aspects of stimuli may explain why non-typical laterality effects have been found in similar research.

Researchers suggest links between mind-wandering and impaired processing of external task stimuli: mind-wandering results in perceptual decoupling. The primary methodology employed to investigate the effects of mind-wandering requires people to report their conscious state and then predicts prior behavior or neurophysiological responses using the person’s self-report. Unfortunately, this method employs reports that occur after the behavior occurs. An alternative methodology employs a word displayed prior to a performance check or catch trial. After the catch trial, participants then report their awareness of the word occurring, attempt to recognize the word, and also report whether they were on- or off-task. We show that participants’ explicit and implicit awareness of the pre-catch trial word is independent of self-reports of conscious state. This finding conflicts with the perspective that mind-wandering reports indicate perceptual decoupling. Reports of mind-wandering may alternatively be how people explain behavioral outcomes.

Sixty participants performed a sustained attention task in which they were required to perform either global or local feature discrimination. Two groups required just one type of discrimination, while the remaining two groups started on one type of discrimination before transitioning to the other type halfway through. A transition resulted in worse performance when compared to no transition. It was also found that the local discrimination group showed improved performance over time compared to the global discrimination group. Functional near-infrared spectroscopy (fNIRS) was used to measure blood oxygenation during the task and was used as an index of cerebral hemodynamic activity. Total oxygenation was found to increase more in global discrimination tasks. It was also found that the left prefrontal cortex showed little change in nontransition tasks while in transition tasks it followed the same trend as the right prefrontal cortex. Combined with performance data, it suggests that an increased utilization of bilateral resources may in some cases improve performance over time.

The abbreviated vigilance task can quickly generate vigilance decrements, which has been argued is due to depletion of cognitive resources needed to sustain performance. Researchers suggest inclusion of rest breaks within vigilance tasks improve overall performance (Helton & Russell, 2015; Ross, Russell, & Helton, 2014), while different types of breaks demonstrate different effects. Some literature suggests exposure to natural movements/stimuli helps restore attention (Herzog, Black, Fountaine, & Knotts, 1997; Kaplan, 1995). Participants were randomly assigned to one experimental condition: dog video breaks, robot video breaks, countdown breaks or continuous vigilance. We assessed task performance and subjective reports of stress/workload. The continuous group displayed worst performance, suggesting breaks help restore attention. The dog videos did not affect performance, however, decreased reports of distress. These results support the importance of rest breaks and acknowledge the benefit of natural stimuli for promoting wellbeing/stress relief, overall suggesting performance and wellbeing may be independent, which warrants future studies.