Surrogate measures: A proposed alternative in human factors assessment of operational measures of performance

Surrogate measures are proposed as an alternative to direct assessment of operational performance for purposes of screening agents who may have to work under unusual stresses or in exotic environments. Such measures are particularly proposed when the surrogate can be empirically validated against the operational criterion. The focus is on cognitive (or throughput) performances in humans as opposed to sensory (input) or motor (output) measures, but the methods should be applicable for development of batteries which will tap input/output functions. A menu of performance tasks is under development for implementation on a battery-operated portable microcomputer, with 21 tests currently available. The tasks are reliable and become stable in minimum amounts of time; appear sensitive to some agents; comprise constructs related to actual job tasks; and are easily administered in most environments. Implications for human factors engineering studies in environmental stress are discussed

Development of microcomputer-based mental acuity tests for repeated-measures studies

The purpose of this report is to detail the development of the Automated Performance Test System (APTS), a computer battery of mental acuity tests that can be used to assess human performance in the presence of toxic elements and environmental stressors. There were four objectives in the development of APTS. First, the technical requirements for developing APTS followed the tenets of the classical theory of mental tests which requires that tests meet set criteria like stability and reliability (the lack of which constitutes insensitivity). To be employed in the study of the exotic conditions of protracted space flight, a battery with multiple parallel forms is required. The second criteria was for the battery to have factorial multidimensionality and the third was for the battery to be sensitive to factors known to compromise performance. A fourth objective was for the tests to converge on the abilities entailed in mission specialist tasks. A series of studies is reported in which candidate APTS tests were subjected to an examination of their psychometric properties for repeated-measures testing. From this work, tests were selected that possessed the requisite metric properties of stability, reliability, and factor richness. In addition, studies are reported which demonstrate the predictive validity of the tests to holistic measures of intelligence

Sustained vigilance is negatively affected by mild and acute sleep loss reflected by reduced capacity for decision making, motor preparation, and execution

© 2018 Sleep Research Society. Study Objectives The behavioral and cognitive consequences of severe sleep deprivation are well understood. Surprisingly, relatively little is known about the neural correlates of mild and acute sleep restriction on tasks that require sustained vigilance for prolonged periods of time during the day. Methods and Results Event-related potential (ERP) paradigms can reveal insight into the neural correlates underlying visual processing and behavioral responding that is impaired with reduced alertness, as a consequence of sleep loss. Here, we investigated the impact of reduced vigilance following at-home mild sleep restriction to better understand the associated behavioral consequences and changes in information processing revealed by ERPs. As expected, vigilance was reduced (e.g. increased lapses and response slowing) that increased over the course of the experiment in the sleep restricted (5 hr sleep) compared with the sleep-extension (9 hr sleep) condition. Corresponding to these lapses, we found decreased positivity of visually evoked potentials in the Sleep Restriction vs. Sleep Extension condition emerging from 316 to 449 ms, maximal over parietal/occipital cortex. We also investigated electrophysiological signs of motor-related processing by comparing lateralized readiness potentials (LRPs) and found reduced positivity of LRPs in the Sleep Restriction vs. Sleep Extension condition at 70-40 ms before, and 115-158 ms after a response was made. Conclusions These results suggest that even a single night of mild sleep restriction can negatively affect vigilance, reflected by reduced processing capacity for decision making, and dulls motor preparation and execution

Sleep and insomnia symptoms in adolescence

Insufficient sleep, sleep problems and insomnia are common in adolescents, and insomnia and insufficient sleep are public health concerns that can impact adolescents’ mental and physical health. There are several different treatments for sleep problems and insomnia, and there is a great focus on the problem when it has already arisen. However, since this is a public health problem, it is important to shed light on it at an early stage, and to inform about adolescents’ sleep problems and insomnia symptoms. This, in hope to help the adolescents’, adults in their environment and professionals in school health care. Aim and methods: The overall aim of this doctoral thesis was to contribute with knowledge about possible factors influencing sleep and insomnia symptoms among adolescents. Paper I investigated adolescents’ experiences regarding what they perceived as facilitators and barriers for a good night´s sleep. This study has a qualitative design, focus groups interviews were performed and analysed with qualitative content analysis. Paper II investigated the associations between insomnia symptoms, academic performance, self-reported health, physical activity, school start time, and substance use in adolescents. This paper was a cross-sectional survey and analysed with descriptive and analytic statistics. Paper III aimed to test the measurement properties of the Minimal Insomnia Symptom Scale (MISS) together with an additional item focusing on daytime functioning, Minimal Insomnia Symptom Scale-Revised (MISS-R) among adolescents. This study has cross-sectional design and data was analysed with Rash measurement model. Paper IV aimed to investigate whether sleep duration, difficulties waking up, tiredness in school, and family financial situation among school-aged girls and boys (aged 6-10 years) can predict insomnia symptoms among female and male adolescents (aged 14-16 years). This was a longitudinal design and was analysed with descriptive and analytic statistics.Results: From paper I emerge that the adolescents were aware of the importance of sleep for managing during the day. However, there were both facilitators and barriers for achieving a good night sleep. Three categories were identified: striving for a sense of well-being, tiring yourself out and regulating electronic media. Paper II highlights that insomnia was associated with poor self-reported health, failed school courses, and use of alcohol and/or cigarettes. When the combined effect of self-reported health and physical activity were investigated, a combination of low physical activity and poor self-reported health was strongly associated with insomnia. Paper III showed that both MISS and MISS-R had good measurement properties, regarding targeting, items tended to represent more severe levels of insomnia symptoms than reported by the adolescents. Older adolescents were more likely to score higher than younger adolescents in the items concerning “problems with not being rested by sleep”, and “problems with daytime disturbance”. Paper IV showed different factors in childhood that predicted insomnia symptoms in adolescence. These factors differed between sex. Perceived quite bad/very bad family financial situation, and short sleep duration at baseline was associated with insomnia symptoms among female adolescents. However, problems waking up at baseline was associated with insomnia symptoms among male adolescents.Conclusions: This thesis shows that the adolescents want to talk about sleep problems and insomnia symptoms with adults in their environment. One instrument that professionals in school health care can have benefit of in the conversation with the adolescents, are MISS-R. MISS-R seem to be a reliable screening instrument for insomnia symptoms among adolescents. The adolescents need support from adults to facilitate a good night sleep

Psychometric Properties of the Oldenburg Burnout Inventory in a Portuguese Sample of Aircraft Maintenance Technicians

Funding: PhD fellowship - PP - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Grant/Award, Number: 88887150178/2017-00.From its initial conceptualization as emotional exhaustion, cynicism, and reduced personal efficacy for the help professions, burnout has received increasing attention in modern times, especially after the 2019 WHO’s inclusion of this syndrome in the ICD-11 list. Burnout can be measured using several psychometric instruments that range in dimensionality, number of items, copyrighted, and free use formats. Here, we report the psychometric properties of data gathered with the Oldenburg Burnout Inventory (OLBI) in a sample of Portuguese Aircraft maintenance technicians. As far as we know, this is the first study addressing the burnout syndrome in this occupational group. Data gathered with the OLBI displayed good evidence of validity related to internal structure, to other variables, with good evidence of reliability. We showed that burnout significantly correlated with mental and physical fatigue emphasizing the vital critical role that these variables play with safety in the aviation industry.publishersversionpublishe

The effect of stimulus threat on experimentally induced secondary hyperalgesia

Background Neuropathic pain affects 7 – 10% of people and responds poorly to pharmacotherapy. Numbers needed to treat for first line drugs range from 4 – 8. Therefore, there is an obvious need for improved understanding of the mechanisms of neuropathic pain to inform improved treatments. Mechanistic research on neuropathic pain frequently uses a human surrogate model of secondary hyperalgesia that is a common feature of neuropathic pain. The value of experimentally inducing secondary hyperalgesia is that one can then test the influence of different pharmacological and nonpharmacological interventions. This may shed some light on the physiological mechanisms within the spinal cord, which possibly also translates to the effects of the interventions on other pathways that are involved in processing signals that may be related to pain. Additionally, pain is known to be influenced by the threat value of the situation. Many South Africans live under constant threat: less than a third of South Africans feel safe walking alone at night. This constant threat may be perpetuating the pain problem in South Arica. However, the mechanism by which threat achieves this influence on pain is unclear. This project is focused on one possible mechanistic hypothesis: that threat influences pain by affecting central physiological changes within the dorsal horn of the spinal cord. These central changes often present clinically as secondary hyperalgesia. A thorough understanding of these mechanisms will inform improved treatment strategies. Methods Phase one: systematic review and meta-analysis The aim of this systematic review was to identify, describe, and compare methods that have been used to manipulate experimentally induced secondary hyperalgesia in healthy humans. A systematic search strategy (conducted on 01 October 2019) was supplemented by reference list checks and direct contact with identified laboratories to maximise the identification of data reporting the experimental manipulation of experimentally induced secondary hyperalgesia in humans. Studies were only included if they were published and in-press or accepted records for which the title, abstract, and full-text versions were available in English. Duplicate screening, risk of bias assessment, and data extraction procedures were used. Risk of bias was appraised for the following domains: selection, performance, detection, attrition, measurement, reporting, and other sources of bias. Data were extracted using a standardised data extraction form. This form was piloted and refined beforehand. Authors were asked to provide data were necessary. Data were pooled by method of v manipulation and outcome (intensity of secondary hyperalgesia, area of secondary hyperalgesia, or both). Phase two: experimental paradigm An experimental study was developed and conducted to investigate the effect of a stimulus threat on secondary hyperalgesia. The aim of this study was to investigate the effect of a manipulation of the threat value of a stimulus on experimentally induced secondary hyperalgesia in healthy human volunteers. All participants underwent a sham skin examination (the threat stimulus) at both the experimental and control sites. Through this sham skin examination, participants were informed that their skin integrity was fragile at the experimental site and robust at the control site. Secondary hyperalgesia was induced with high-frequency electrical stimulation at both the experimental and control site. Sensory testing was conducted at the experimental and control site, providing a withinsubject comparison of the intensity and area of secondary hyperalgesia at each site. It was hypothesised that greater threat will be associated with (hypothesis 1) greater intensity and (hypothesis 2) greater surface area of induced secondary hyperalgesia. Results Phase one: systematic review Twenty-one studies with non-pharmacological manipulations were included. Nine (out of 21) studies assessed intensity of secondary hyperalgesia after manipulation. Nicotine deprivation and negative expectations about the induction increased the intensity of secondary hyperalgesia. Three studies using attentional modulation and cognitive loading reported conflicting results with two studies having no effect and the other reporting a decrease in the intensity of secondary hyperalgesia. Emotional disclosure decreased the intensity of secondary hyperalgesia at four days and at one month after the manipulation. Hot/cold application, and verbal suggestion had no effect on the intensity of secondary hyperalgesia. Seventeen (out of 21) studies assessed area of secondary hyperalgesia after manipulation. Nicotine deprivation and sleep deprivation increased the area of secondary hyperalgesia. Hyperbaric oxygen therapy, cognitive behavioural therapy, emotional disclosure, spinal manipulation, transcranial direct current stimulation, and placebo analgesia decreased the area of secondary hyperalgesia. Interestingly, the effects of emotional disclosure and hyperbaric oxygen therapy were evident one month after manipulation. Acupuncture had no significant effect on the area of secondary hyperalgesia. Four studies assessed the effect of hot/cold application. Three studies reported no effect and one study reported an increase in the area of secondary hyperalgesia after cold application

Mind Wandering and Sleep in Daily Life: A Combined Actigraphy and Experience Sampling Study

Individuals who sleep poorly report spending more time mind wandering during the day. However, past research has relied on self-report measures of sleep or measured mind wandering during laboratory tasks, which prevents generalization to everyday contexts. We used ambulatory assessments to examine the relations between several features of sleep (duration, fragmentation, and disturbances) and mind wandering (task-unrelated, stimulus-independent, and unguided thoughts). Participants wore a wristband device that collected actigraphy and experience-sampling data across 7 days and 8 nights. Contrary to our expectations, task-unrelated and stimulus-independent thoughts were not associated with sleep either within- or between-persons (n = 164). Instead, individual differences in unguided thoughts were associated with sleep disturbances and duration, suggesting that individuals who more often experience unguided train-of- thoughts have greater sleep disturbances and sleep longer. These results highlight the need to consider the context and features of mind wandering when relating it to sleep