Positive post‐disaster images: A daydream machine?

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.     

Lack of habituation to shocking words: The attentional bias to their spatial origin is context free

Following a suggestion made by Aquino and Arnell (2007), we assumed that the processing of emotional words is influenced by their context of presentation. Supporting this idea, previous studies using the emotional Stroop task in its visual or auditory variant revealed different results depending on the mixed versus blocked presentation of the stimuli (Bertels, Kolinsky, Pietrons, & Morais, 2011; Richards, French, Johnson, Naparstek, & Williams, 1992). In the present study, we investigated the impact of these presentation designs on the occurrence of spatial attentional biases in a modified version of the beep-probe task (Bertels, Kolinsky, & Morais, 2010). Attentional vigilance to taboo words as well as non-spatial slowing effects of these words were observed whatever the mixed or blocked design, whereas attentional vigilance to positive words was only observed in the mixed design. Together with the results from our previous study (Bertels et al., 2010), the present data support the reliability of the effects of shocking stimuli, while vigilance to positive words would only be observed in a threatening context.     

Mental effort causes vigilance decrease due to resource depletion

The resource view on vigilance performance was tested. First, a low demanding task was compared with a similar low demanding task in which stimulus presentation was less monotonous due to added, irrelevant, stimuli. The resource view, maintaining that vigilance is lowered by hard mental work, predicts that addition of irrelevant stimuli will not affect performance. The classic arousal theory, however, states that arousal drops due to monotonous stimulus presentation and predicts that decreasing monotony will enhance performance. Results showed that performance was unaffected by added stimuli. Second, we tested whether a high-demanding task (with identical stimulus presentation as the low demanding task, but different instruction) would cause a greater decline in performance than the low demanding task. Indeed, in the high-demanding task performance was affected most. In sum, it appears that vigilance decreases due to hard mental work, which requires many resources. Both overall performance and decrement in performance can be explained in terms of resources, and this suggests that vigilance tasks should be resource-demanding tasks, which do not have to be of long duration.     

Interactions between endogenous and exogenous attention during vigilance

The ability to remain vigilant over long periods of time is critical for many everyday tasks, but controlled studies of visual sustained attention show that performance declines over time when observers are required to respond to rare stimulus events (targets) occurring in a sequence of standard stimulus events (nontargets). When target discrimination is perceptually difficult, this vigilance decrement manifests as a decline in perceptual sensitivity. We examined whether sudden-onset stimuli could act as exogenous attentional cues to improve sensitivity during a traditional sustained attention task. Sudden-onset cues presented immediately before each stimulus attenuated the sensitivity decrement, but only when stimulus timing (the interstimulus interval [ISI]) was constant. When stimulus timing was variable, exogenous cues increased overall sensitivity but did not prevent performance decline. Finally, independent of the effects of sudden onsets, a constant ISI improved vigilance performance. Our results demonstrate that exogenous attention enhances perceptual sensitivity during vigilance performance, but that this effect is dependent on observers’ being able to predict the timing of stimulus events. Such a result indicates a strong interaction between endogenous and exogenous attention during vigilance. We relate our findings to a resource model of vigilance, as well as to theories of endogenous and exogenous attention over short time periods.     

A Walk Down the Lane Gives Wings to Your Brain. Restorative Benefits of Rest Breaks on Cognition and Self‐Control

We investigated the effect of rest breaks on mental‐arithmetic performance, examining performance as a function of the factor rest, time‐on‐task, and demand. We asked the following questions: (i) Does rest (vs a continuous‐work condition) improve cognitive performance? (ii) Is active rest (taking a walk) better than passive rest (watching a video)? (iii) Do compensatory effects of rest increase with time‐at‐work? (iv) Are there differential effects of rest on automatic and controlled processes? (v) Are there differential effects of rest on performance speed versus variability? The results indicate that while rest is generally beneficial for performance, these benefits are similar for active and passive rest. The benefits increase with time‐on‐task and are larger for high (vs low) demand. Further, the effects on average response speed originated only partially from a reduction in the probability of attentional failure, as indicated by reaction‐time (ex‐Gaussian model) distributional and delta‐plot analysis.Copyright © 2016 John Wiley & Sons, Ltd.     

Examining the role of emotional valence of mind wandering: All mind wandering is not equal

To evaluate the role of emotional valence on the impact of mind wandering on working memory (WM) and sustained attention, we reanalyzed data from three independently conducted studies that examined the impact of stress on WM (Banks & Boals, 2016; Banks, Welhaf, & Srour, 2015) and sustained attention (Banks, Tartar, & Welhaf, 2014). Across all studies, participants reported the content of their thoughts at random intervals during the WM or sustained attention task. Thought probes in all studies included a core set of response options for task-unrelated thoughts (TUTs) that were negatively, positively, or neutrally emotionally valenced. In line with theories of emotional valenced stimuli on capture of attention, results suggest negatively valenced TUTs, but not positively valenced TUTs, were related to poorer WM and sustained attention in two studies. Neutral TUTs were related to poorer WM but not sustained attention performance. Implications for models of mind wandering are discussed.     

Natural scene stimuli and lapses of sustained attention

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.     

Shared and distinct factors driving attention and temporal processing across modalities

In addition to the classic finding that “sounds are judged longer than lights,” the timing of auditory stimuli is often more precise and accurate than is the timing of visual stimuli. In cognitive models of temporal processing, these modality differences are explained by positing that auditory stimuli more automatically capture and hold attention, more efficiently closing an attentional switch that allows the accumulation of pulses marking the passage of time (Penney, Gibbon, & Meck, 2000). However, attention is a multifaceted construct, and there has been little attempt to determine which aspects of attention may be related to modality effects. We used visual and auditory versions of the Continuous Temporal Expectancy Task (CTET; O'Connell et al., 2009) a timing task previously linked to behavioral and electrophysiological measures of mind-wandering and attention lapses, and tested participants with or without the presence of a video distractor. Performance in the auditory condition was generally superior to that in the visual condition, replicating standard results in the timing literature. The auditory modality was also less affected by declines in sustained attention indexed by declines in performance over time. In contrast, distraction had an equivalent impact on performance in the two modalities. Analysis of individual differences in performance revealed further differences between the two modalities: Poor performance in the auditory condition was primarily related to boredom whereas poor performance in the visual condition was primarily related to distractibility. These results suggest that: 1) challenges to different aspects of attention reveal both modality-specific and nonspecific effects on temporal processing, and 2) different factors drive individual differences when testing across modalities.     

Inattentional blindness for ignored words: Comparison of explicit and implicit memory tasks

Inattentional blindness is described as the failure to perceive a supra-threshold stimulus when attention is directed away from that stimulus. Based on performance on an explicit recognition memory test and concurrent functional imaging data Rees, Russell, Frith, and Driver [Rees, G., Russell, C., Frith, C. D., & Driver, J. (1999). Inattentional blindness versus inattentional amnesia for fixated but ignored words. Science, 286, 2504–2507] reported inattentional blindness for word stimuli that were fixated but ignored. The present study examined both explicit and implicit memory for fixated but ignored words using a selective-attention task in which overlapping picture/word stimuli were presented at fixation. No explicit awareness of the unattended words was apparent on a recognition memory test. Analysis of an implicit memory task, however, indicated that unattended words were perceived at a perceptual level. Thus, the selective-attention task did not result in perfect filtering as suggested by Rees et al. While there was no evidence of conscious perception, subjects were not blind to the implicit perceptual properties of fixated but ignored words.     

Action video game experience reduces the cost of switching tasks

Video game expertise has been shown to have beneficial effects for visual attention processes, but the effects of action video game playing on executive functions, such as task switching and filtering out distracting information, are less well understood. In the main experiment presented here, video game players (VGPs) and nonplayers (nVGPs) switched between two tasks of unequal familiarity: a familiar task of responding in the direction indicated by an arrow, and a novel task of responding in the opposite direction. nVGPs had large response time costs for switching from the novel task to the familiar task, and small costs for switching from the familiar task to the novel task, replicating prior findings. However, as compared to the nVGPs, VGPs were more facile in switching between tasks, producing overall smaller and more symmetric switching costs, suggesting that experience with action video games produces improvements in executive functioning. In contrast, VGPs and nVGPs did not differ in filtering out the irrelevant flanking stimuli or in remembering details of aurally presented stories. The lack of global differences between the groups suggests that the improved task-switching performance seen in VGPs was not due to differences in global factors, such as VGPs being more motivated than nVGPs.     

Differential relationship of recent self-reported stress and acute anxiety with divided attention performance

There have been relatively few studies on the relationship between recent perceived environmental stress and cognitive performance, and the existing studies do not control for state anxiety during the cognitive testing. The current study addressed this need by examining recent self-reported environmental stress and divided attention performance, while controlling for state anxiety. Fifty-four university undergraduates who self-reported a wide range of perceived recent stress (10-item perceived stress scale) completed both single and dual (simultaneous auditory and visual stimuli) continuous performance tests. Partial correlation analysis showed a statistically significant positive correlation between perceived stress and the auditory omission errors from the dual condition, after controlling for state anxiety and auditory omission errors from the single condition (r = 0.41). This suggests that increased environmental stress relates to decreased divided attention performance in auditory vigilance. In contrast, an increase in state anxiety (controlling for perceived stress) was related to a decrease in auditory omission errors from the dual condition (r = - 0.37), which suggests that state anxiety may improve divided attention performance. Results suggest that further examination of the neurobiological consequences of environmental stress on divided attention and other executive functioning tasks is needed.     

Contextual factors in vigilance testing of children with ADHD

The effect of contextual factors on continuous performance testing was examined by administering a vigilance task to 51 children with ADHD under conditions of examiner presence and absence at different times (i.e., beginning and middle) of an assessment battery. The results showed that the ability to differentiate target stimuli from distractors (d-prime) was related to examiner presence vs. absence, and that response bias (beta), a measure of the subject's carefulness in responding to stimuli, was associated with the time of task administration. The decline in d-prime under conditions of examiner absence was shown to be related more to level of aggression as opposed to level of inattention. Children with ADHD having relatively high levels of aggression demonstrated a significant decline in d-prime scores under conditions of examiner absence, but those with relatively low levels of aggression did not. The results demonstrated the importance of contextual factors on vigilance task performance and suggested a differential impact of contextual variables on children who are inattentive vs. aggressive.     

在不同事件率条件下人格倾向类型对认知性警戒的影响

本研究采用两种事件率 ,考察了人格倾向类型对认知性警戒的影响。实验结果表明 :(1 )事件率是影响作业绩效的一个重要因素。事件率与人格倾向存在着交互作用。 (2 )认知性警戒作业的应激效应与事件率有关 ,随着事件率的上升 ,受试者在作业过程中的应激水平明显增高。 (3 )根据对被试自觉疲劳的测量结果 ,在认知性警戒作业中 ,内倾者与外倾者间应激水平存在差异。     

Plasma Catecholamine and Performance Associations During Psychological Stress: Evidence for Peripheral Noradrenergic Involvement With an Attention-Demanding Task

The purpose of this investigation was to examine the associations between plasma catecholaminc (CA) response and selected performance measures during psychological stress. Nineteen men (between the ages of 35 and 50) performed a double-conflict (DC) task for 12 min. Self-reported distress resulting from the stress protocol was assessed using the Profile of Mood States and the Spielberger State-Trait Anxiety Inventory. Performance of the DC task was measured by total reaction time (TRT). Cognitive aftereffects were assessed by the time it took to complete three sets of anagrams administered immediately after the DC task. Plasma CA measures were taken at three intervals during the rest period and the DC task. The stress protocol resulted in increased self-reported tension, p ≤ 0.01; confusion, p ≤ 0.01; and anxiety, p ≤ 0.01; with reduced vigor, p less than or equal to 0.01. The men displayed improved TRT, p less than or equal to 0.01, during the DC task, and they had significantly extended performance time, p less than or equal to 0.01, on anagram Set 1 compared to Sets 2 and 3. Although both plasma norepinephrine (NE) and plasma epinephrine (E) increased, only E achieved statistical significance, p less than or equal to 0.05. The only significant correlation between plasma CA and performance occurred with NE and anagram Set 1, p less than or equal to 0.05. The findings arc discussed in terms of a postulated link between circulating NE and cognitive effects of stress.     

Event-related cerebral hemodynamics reveal target-specific resource allocation for both “go” and “no-go” response-based vigilance tasks

Transcranial Doppler sonography was used to measure cerebral blood flow velocity (CBFV) in the right and left cerebral hemispheres during the performance of a 50-min visual vigilance session. Observers monitored a simulated flight of unmanned aerial vehicles for cases in which one of the vehicles was flying in an inappropriate direction relative to its cohorts. Two types of vigilance tasks were employed: a traditional task in which observers made button press (“go”) responses to critical signals, and a modification of the traditional task called the Sustained Attention to Response Task (SART) in which “go” responses acknowledged nonsignal events and response withholding (“no-go”) signified signal detection. Signal detections and global CBFV scores declined over time. In addition, fine-grained event-related analyses revealed that the detection of signals was accompanied by an elevation of CBFV that was not present with missed signals. As was the case with the global scores, the magnitude of the transient CBFV increments associated with signal detection also declined over time, and these findings were independent of task type. The results support the view of CBFV as an index of the cognitive evaluation of stimulus significance, and a resource model of vigilance in which the need for continuous attention produces a depletion of information-processing assets that are not replenished as the task progresses. Further, temporal declines in the magnitude of event-related CBFV in response to critical signals only is evidence that the decrement function in vigilance is due to attentional processing and not specific task elements such as the required response format.     

Switching attentional focus across internal and external cues improves performance in a rowing task in novices

Performance in skill-based and endurance sports can be enhanced when an individual directs attention toward internal or external cues. However, there might be advantages in attending to specific cues at different times during a continuous sport task. The present study examined the effects of switching attention between internal and external cues when rowing. Novice rowers (N = 27) completed three 2000 m rows while focusing attention on internal cues only, external cues only, or switching between internal and external cues. Overall performance, as measured by time and power output, was best in the switching condition. Measurements of heart rate and perceived exertion were not significantly different between switching and external conditions, suggesting that these performance improvements occurred without producing significant subjective or objective physiologic change. However, a focus on external cues resulted in lower ratings of perceived exertion relative to a focus on internal cues. Self-reported motivation did not differ between conditions. Although instructions to focus internally or externally can influence performance on aerobic tasks, switching attention between these cues may enhance performance. Athletes should consider attending to various cues in rowing and, by extension, in other endurance sports.     

Eye Metrics: An Alternative Vigilance Detector for Military Operators

Military operators in various environments such as cyber, remotely piloted aircraft, and image analysis are required to use sustained attention or vigilance for long periods. During this time they encounter lapses in attention attributable to the monotonous nature of their tasks. Mistakes during these tasks can have serious consequences. The purpose of this study was to investigate the use of an eye-tracker to detect changes in vigilance performance during a simulated cyber operator task. Twenty participants performed 4 sessions of a 40-min vigilance task while wearing an eye-tracker. Blink frequency, blink duration, PERCLOS (percentage of eye closure), pupil diameter, pupil eccentricity, pupil velocity, and signal detection all had a significant change over time (p < .05) during the task. The significant change of oculometric measurements indicates oculometrics could be used to detect changes in vigilance for military operators. Future research is needed to assess real-time effects of these oculometrics on performance, especially in a real-world setting.     

Vigilance, personality and strength of the nervous system

Numerous attempts have been made to explain the overall level of performance and the change in performance over time in vigilance tasks in terms of the proposed inverted U relationship between performance and ‘arousal’. The present experiment investigated the effects on vigilance performance of the following variables: introversion, neuroticism, time of day, accessory sensory stimulation, ‘signal frequency’ and time on task. Some measures of subjective state and body temperature were also included. The behavioural measures of overall performance revealed interactions involving neuroticism and time of day, and between neuroticism and frequency. This may reflect the operation of response bias factors, though these may be influenced by ‘arousal’. There were also main effects for several of the factors which may have practical significance. There was a significant effect of time on task on all the behavioural measures but no clearcut effects of personality on the vigilance ‘decrement’. It is argued that the latter may not provide the most satisfactory test of the inverted U model and its relationship to personality. However, interactions between noise and time on task for some of the measures may have practical importance. Measures of subjective state showed a fall in the reported level of ‘arousal’ accompanied by a rise in reported ‘stress’ and ‘anxiety’ with time on task. Body temperature was higher after the task than before.     

休息对自我损耗的补偿作用

两个实验旨在检验自我损耗效应并探讨休息对自我损耗的补偿作用。在实验1中,损耗组被试通过观看注意控制视频诱发自我控制资源的损耗,然后完成Stroop任务。实验2与实验1的不同之处在于,诱发自我损耗后进行不同时间（5分钟、10分钟）的休息处理。两个实验结果发现：（1）注意控制视频成功诱发了自我损耗效应;（2）休息对自我损耗具有补偿作用;（3）在损耗状态下,休息5分钟即对自我控制资源具有补偿作用。研究结果证实了自我损耗的资源枯竭观。     

Chewing gum moderates the vigilance decrement

We examine the impact of chewing gum on a Bakan‐type vigilance task that requires the continual updating of short‐term order memory. Forty participants completed a 30‐min auditory Bakan‐task either with, or without, the requirement to chew gum. Self‐rated measures of mood were taken both pre‐ and post‐task. As expected, the vigilance task produced a time‐dependent performance decrement indexed via decreases in target detections and lengthened correct reaction times (RTs), and a reduction in post‐task self‐rated alertness scores. The declines in both performance and subjective alertness were attenuated in the chewing‐gum group. In particular, correct RTs were significantly shorter following the chewing of gum in the latter stages of the task. Additionally, the gradients of decline for target detection and incline for correct RTs were both attenuated for the chewing‐gum group. These findings are consistent with the data of Tucha and Simpson (2011), Appetite, 56, 299–301, who showed beneficial effects of chewing gum in the latter stages of a 30 min visual attention task, and extend their data to a task that necessitates the continuous updating of order memory. It is noteworthy that our data contradict the claim (Kozlov, Hughes, & Jones, 2012, Q. J. Exp. Psychology, 65, 501–513) that chewing gum negatively impacts short‐term memory task performance.