The Effects of Sleep Time and Power Napping on Memory and Vigilance

This research investigated the effects of power napping and sleep time on verbal and visual memory performance and vigilance levels. This research was conducted because there is limited prior research that determines the beneficial effects of power napping on both verbal and visual memory performance and vigilance levels. In addition, prior research has concluded that going to sleep early enhances memory and vigilance. However the interaction of sleep time and power napping has not yet been investigated. This research hypothesised that power napping would significantly increase verbal and visual memory performance, as well as vigilance levels. It further hypothesised that participants who go to sleep late (after midnight) would benefit significantly more from a power nap, enhancing verbal and visual memory performance and increasing vigilance levels, in comparison to those who go to sleep early (before midnight). This research drew on the findings of prior research which investigated the impact of circadian rhythms and the stages of sleep on performance. This experiment included 80 participants, 40 participants engaged in a 20 minute power nap whilst the other 40 participants engaged in a 20 minute rest period which involved reading magazines. In the power napping condition and non-power napping condition, 20 participants went to sleep before midnight and 20 participants went to sleep after midnight the night prior to the experiment. All 80 participants completed a verbal memory test, a visual memory test and a vigilance test. The results of the experiment found that engaging in a power nap did significantly increase verbal and visual memory, and participants who went to sleep after midnight had significantly increased verbal and visual memory performance in the power napping condition, compared to those who went to sleep before midnight. However, there were no significant difference between the power napping condition and non-power napping condition with regards to vigilance levels. There were also no significant difference between the early sleep time condition and late sleep time condition in the power napping condition on vigilance levels

Friendly Fire and the Sustained Attention to Response Task

Objective: We investigated whether losses of inhibitory control could be responsible for some friendly-fire incidents. Background: Several factors are commonly cited to explain friendly-fire incidents, but failure of inhibitory control has not yet been explored. The Sustained Attention to Response Task (SART) could be a valid model for inhibition failures in some combat scenarios. Method: Participants completed small-arms simulations using near infrared emitter guns, confronting research assistants acting as friends or foes. In Experiment 1, seven participants completed three conditions with three different proportions of foes (high, medium, low). In Experiment 2, 13 participants completed high-foe (high-go) and low-foe (low-go) versions of a small-arms simulation as well as comparative computer tasks. Results: Participants made more friendly-fire errors (errors of commission) when foe proportion was high. A speed–accuracy trade-off was apparent, with participants who were faster to fire on foes also more likely to accidentally shoot friends. When foe proportion was higher, response times to foe stimuli were faster, and subjective workload ratings were higher. Conclusion: Failures of inhibitory control may be responsible for some friendly-fire incidents and the SART could be a suitable empirical model for some battlefield environments. The effect appears to be disproportionately greater at higher foe proportions. The exact nature of performance reductions associated with high-foe proportions requires further investigation. Application: The SART may be a useful model of friendly-fire scenarios. It could be used to indicate a soldier’s likelihood to commit a friendly-fire mistake and to identify high-risk environments

Real life does not always get in the way: verbal memory and the Sustained Attention to Response Task

The Sustained Attention to Response Task (SART) is a go/no-go task where participants must respond frequently to target stimuli and withhold responses from infrequent neutral stimuli. Researchers have shown that the fast and frequent responding characteristic of SART is typically associated with difficulty withholding responses to no-go stimuli. Imposing additional cognitive demands has been shown to further impair task performance. In the present research, participants completed a modified SART task, a narrative memory task, and a dual-task condition where both were done simultaneously. No significant performance impairments were found in the dual- compared to single-task conditions. The tasks’ non-overlapping resource demands, alongside a potential arousing benefit of the memory task, may explain the lack of notable dual-task interference. Future research is needed to better understand the effects of arousal and other factors that may help to uncouple errors of commission from response time, particularly in tasks with high ecological validity

Beyond Compliance: Examining the Role of Motivation in Vigilance Performance

Vigilance, or sustained attention, is the capacity to attend to information for a prolonged period of time (Davies & Parasuraman, 1982; Jerison, 1970; Warm, 1977). Due to limitations of the human nervous system, as well as the environmental context, attention can begin to wane over time. This results in a phenomenon referred to as the vigilance decrement, or a decline in vigilance performance as a function of time. The vigilance decrement can manifest as poorer attention and is thusly associated with poor performance, which is defined behaviorally as more lapses in the detection of critical signals and an increase in response time to these signals during watch. Given this, the present dissertation seeks to systematically examine the impact of two types of motivation (i.e., achievement motivation, autonomous motivation) on vigilance performance across four experiments. The present experiments manipulate information processing type, source complexity, and motivational task demands. Three hundred and ninety-eight participants completed either a cognitive task or sensory task, which were psychophysically equated in previous studies (Szalma & Teo, 2012; Teo, Szalma, & Schmidt, 2011), with or without motivational instructions, and with either low, medium, or high source complexity. Performance measures, perceived stress and workload, and changes to state motivation and engagement at pre-task and post-task are interpreted across three theories of information processing: resource-depletion theory, mind-wandering theory, and mindlessness theory. The results of each of the four studies are discussed in terms of overall support for the resource-depletionist account. The limitations of the present set of experiments and the future directions for research on motivation and sustained attention are also discussed

Vigilance of Certified Registered Nurse Anesthetists

Vigilance of certified registered nurse anesthetists (CRNAs) is an integral component of the care they provide patients under general anesthetic. the practice of CRNas is important as the official seal of the American Association of Nurse Anesthetists (AANA). on the seal, Morpheus, the god of dreams, is shown holding the Lamp of Learning, by the light of which he keeps vigil (Hirter & Van Nest, 1995). as the patients remain unconscious under general anesthesia, CRNas remain the patients\u27 eyes and ears remains responsive to their needs. the CRNa must remain attentive to the patient\u27s needs by continuously monitoring the patient in the operating room and constantly communicating with the operating room staff. Complete focus must be maintained to avoid any mishaps or adverse events. in essence, CRNas must remain focused and vigilant when caring for their patients. the importance of vigilance is essential and undeniable for optimal patient outcomes, but the process has yet to be defined and understood. Fourteen CRNas participated in phone interviews in this study. CRNas practicing in both hospital and ambulatory settings were included. Through data analysis, using constant comparison, a model emerged that explained vigilance in the CRNa process. the core category was Using Senses, and the model had seven subcategories. the categories below reflected stages in the process model. the process begins with the CRNA\u27s care of the patient (Being Alert). This is when the CRNa assumes care of the patient, maintains a high level of alertness, and does not get mentally fatigued. Being alert allows the CRNa to be ready to care for their patients. When CRNas are alert, they are attentive and engaged (Being Attentive and Engaged) in watching over their patients. This allows the CRNa to be constantly aware and pay attention to their patients. Being attentive and engaged allows the CRNa to be focused (Focusing) on every aspect of patient care. Unfortunately, the operating room is a dynamic environment, where distractions, such as music, conversation, and technology can distract clinicians from being engaged in the care of their patients. These distractions can, but do not always, occur. When they do occur, the CRNa redirects their attention and begins to focus, which allows CRNas to use their senses to look, listen, and feel (Looking, Listening, and Touching). Using the senses of looking, listening, and feeling, the CRNa can pick up on events or look for cues that can help continue or improve care by anticipating changes at random intervals during the case. by using their senses and picking up on cues, the CRNa knows what is going on with the patient (Know What Is Happening). the findings of this study have implications for nurse administrators. This theory will be informative and helpful for hospital administrators, as they may want to implement a policy similar to that which the aviation industry developed for pilots reporting for duty. in regards to nursing research, the Institute of Medicine ([IOM], 2003) has used the phenomena of vigilance and surveillance interchangeably, but the processes are not interchangeable. There is a distinction between these two concepts. This study provides a link between the two phenomena. Vigilance is a link to the process of surveillance and studying it will help the researcher expound upon the previous surveillance research in nursing

In every given moment : the affective, cognitive and physiological concomitants of mindfulness

Includes bibliographical references (leaves 64-71).An impressive collection of research has shown that mindfulness - described as a heightened awareness of the present moment - nurtures inner resources for reducing stress, and improving well-being. The aim of this study was to further validate, and add to these findings by illustrating the relationship between mindfulness and affect, cognition and physiological reactivity to stress

The independence and interdependence of coacting observers in regard to performance efficiency, workload, and stress in a vigilance task

Objective We investigated performance, workload, and stress in groups of paired observers who performed a vigilance task in a coactive (independent) manner. Background Previous studies have demonstrated that groups of coactive observers detect more signals in a vigilance task than observers working alone. Therefore, the use of such groups might be effective in enhancing signal detection in operational situations. However, concern over appearing less competent than one's cohort might induce elevated levels of workload and stress in coactive group members and thereby undermine group performance benefits. Accordingly, we performed the initial experiment comparing workload and stress in observers who performed a vigilance task coactively with those of observers who performed the vigilance task alone. Method Observers monitored a video display for collision flight paths in a simulated unmanned aerial vehicle control task. Self-reports of workload and stress were secured via the NASA-Task Load Index and the Dundee Stress State Questionnaire, respectively. Results Groups of coactive observers detected significantly more signals than did single observers. Coacting observers did not differ significantly from those operating by themselves in terms of workload but did in regard to stress; posttask distress was significantly lower for coacting than for single observers. Conclusion Performing a visual vigilance task in a coactive manner with another observer does not elevate workload above that of observers working alone and serves to attenuate the stress associated with vigilance task performance. Application The use of coacting observers could be an effective vehicle for enhancing performance efficiency in operational vigilance

Mechanisms of Vigilance Loss in Sensory and Cognitive Tasks

When observers monitor for infrequent signals for extended durations, they generally experience a decline in detections over time. This decline is termed the vigilance decrement. Current theories of vigilance attribute the decrement to three potential mechanisms: conservative shifts in response bias, losses of sensitivity, and an increased rate of attentional lapses over time. Understanding which mechanisms contribute to the losses of vigilance is necessary to mitigate the decrement in applied settings. Unfortunately, much of the existing literature examining vigilance performance relies on measures that are not suited for distinguishing between all three proposed mechanisms. Using novel methods of analysis, the present project examined the extent to which bias shifts, sensitivity losses, and attentional lapses contributed to the vigilance decrement across a range of vigilance tasks. Study 1 (Chapter 3) used psychometric curves to analyze changes in response bias, sensitivity, and lapse rate in two online vigilance tasks. Data showed that the decrement was largely driven by an attentional lapses and conservative shifts in bias over time, with inconclusive evidence for a sensitivity loss. Study 2 (Chapter 4) presents a generative process model to simulate cognitive mechanisms directly and tests the adequacy of the model by reanalyzing data previously fitted with psychometric curves. Results provide converging evidence that the decrement was driven by attentional lapses and shifts in bias. Study 3 (Chapter 5) uses the generative model to assess vigilance performance within a cognitive vigilance task. Vigilance was relatively stable in the cognitive task and data gave strong evidence that the decrement, albeit small, was driven by an increase in attentional lapses. Together, findings provide strong evidence that vigilance decrement is driven by attentional lapses, followed by conservative shifts in bias. Relatively weak evidence for sensitivity loss. Suggests interventions that target lapses and response criteria most effective for minimizing vigilance losses in applied settings

Intentional and Unintentional Task-Unrelated Thought: Separable Associations and Outcomes in the Lab and Daily Life

Mind wandering is a ubiquitous experience, which encompasses many different types of thought. Task-unrelated thought (TUT) is a commonly studied type of mind wandering and refers to thoughts which occur during the completion of an ongoing task, but which are unrelated to that ongoing task. Importantly, these TUTs can be engaged either intentionally or unintentionally and there is a growing body of evidence which documents and supports these types of TUTs as being meaningfully different in terms of their underpinning mechanisms, their phenomenological experience, and their outcomes. It is necessary to continue to study and document their differences, as this may assist in further understanding some of the more ambiguous or conflicting findings from TUT literature. Consequently, this thesis aims to measure and investigate differences between intentional and unintentional TUTs across three areas of interest: task context, cognitive ability, and social functioning. Examination of the variable of intention in these areas may elucidate apparent contradictory observations within them. In addition, this thesis will investigate TUTs both in the laboratory and in daily life, to contribute to an understanding of intentional and unintentional TUTs across a broader scope of situations. In doing so, this thesis supports existing arguments that intention should be explicitly considered in mind wandering theory, in order to better predict and account for the occurrence and consequences of TUTs

Exploring the Role of the Dorsal Attention Network in Sustained Attention With rTMS

Sustained attention that is effortful during challenging cognitive tasks has been associated with robust activity in brain areas involved with cognitive control, collectively referred to as the dorsal attention network (DAN). In contrast, the periods of optimal sustained attention have been associated with relatively less DAN activity than periods of struggle. Optimal sustained attention may be less dependent on DAN function and more dependent on brain networks related to task automation such as the default mode network (DMN). Alternatively, optimal sustained attention may be recruiting DAN function efficiently, thus resulting in less overall activity. These two hypotheses were examined by temporarily disrupting DAN activity by applying repetitive transcranial magnetic stimulation (rTMS) to the frontal eye fields (FEF) in the DAN and then measuring sustained attention to a cognitive task. Subjects randomly received real or sham rTMS to the left or right FEF and then performed a modified go/no-go sustained attention task referred to as the gradCPT. For subjects receiving real rTMS to the right FEF, response accuracy decreased and reaction time variability increased on the gradCPT during periods of optimal sustained attention. The findings suggest that optimal sustained attention to cognitive tasks is supported by the refined, economical recruitment of right hemisphere DAN function