Vigilance: Where Has All the Workload Gone?

1993 ◽  
Vol 37 (19) ◽  
pp. 1383-1387 ◽  
Author(s):  
David A. Sawin ◽  
Mark W. Scerbo
Keyword(s):  
False Alarm ◽  
Perceptual Sensitivity ◽  
Video Display ◽  
Task Load ◽  
Time Performance ◽  
Instruction Type ◽  
Before And After ◽  
Different Color ◽  
Nasa Task Load Index ◽  
Over Time

The present study explored whether instructions given to subjects at the outset of a vigilance experiment impact their ratings of frustration and workload. The present task consisted of monitoring a video display terminal (VDT) of uniform color for 30 min. Subjects were asked to respond to occasional 3 ms “flickers” to a different color. Half of the subjects were told to relax by focusing on the display, but to respond to any flickers observed. The remaining subjects were given traditional vigilance instructions emphasizing the importance of detecting as many “critical signals” or flickers as possible. Before and after the vigil, subjects completed the NASA Task Load Index (TLX; Hart and Staveland, 1988) which measured the subjective workload for the vigil. Hits and false alarm data were recorded for each 10 min period within the 30 min vigil. A significant reduction in mean number of hits was observed over the three periods for all subjects. A subsequent analysis showed that perceptual sensitivity also declined significantly over time. Performance, however, was not affected by instruction type. Subjects who received relaxation-emphasis instructions did report significantly lower workload and frustration for the vigil than those receiving detection-emphasis instructions. These results indicate that much of what individuals find unpleasant about participating in vigilance experiments may lie with the expectations outlined in the initial instructions.

scholarly journals Surgery Task Load Index in Cardiac Surgery: Measuring Cognitive Load Among Teams

2020 ◽  
pp. 155335062093493
Author(s):  
Lauren R. Kennedy-Metz ◽  
Hill L. Wolfe ◽  
Roger D. Dias ◽  
Steven J. Yule ◽  
Marco A. Zenati
Keyword(s):  
Cardiac Surgery ◽  
Cognitive Load ◽  
Subjective Assessment ◽  
Team Members ◽  
Task Load ◽  
Surgical Complexity ◽  
General Populations ◽  
Nasa Task Load Index ◽  
The Relationship ◽  
Over Time

Background. The most commonly used subjective assessment of perceived cognitive load, the NASA Task Load Index (TLX), has proven valuable in measuring individual load among general populations. The surgery task load index (SURG-TLX) was developed and validated to measure cognitive load specifically among individuals within a surgical team. Notably, the TLX lacks temporal sensitivity in its typical retrospective administration. Objective. This study sought to expand the utility of SURG-TLX by investigating individual measures of cognitive load over time during cardiac surgery, and the relationship between individual and team measures of cognitive load and proxies for surgical complexity. Materials & Methods. SURG-TLX was administered retrospectively in the operating room immediately following each case to approximate cognitive load before, during, and after cardiopulmonary bypass for cardiac surgery team members (surgeon, anesthesiologist, and perfusionist). Correlations were calculated to determine the relationship of individual and team measures of cognitive load over the entire procedure with bypass length and surgery length. Results. Results suggest that perceived cognitive load varies throughout the procedure such that cognitive load during bypass significantly differs compared to before or after bypass, across all 3 roles. While on bypass, results show that anesthesiologists experience significantly lower levels of perceived cognitive load than both surgeons and perfusionists. Correlational analyses reveal that perceived cognitive load of both the surgeon and the team had significant positive associations with bypass length and surgery length. Conclusion. Our findings support the utility of SURG-TLX in real cardiac cases as a measure of cognitive load over time, and on an individual and team-wide basis.

Examining the effects of stress on the driving abilities of paramedic students

2019 ◽  
Vol 9 (4) ◽  
pp. 76-83
Author(s):  
Trevor Hines Duncliffe ◽  
Brittany D'Angelo ◽  
Michael Brock ◽  
Cal Fraser ◽  
Jake Lamarra ◽  
...  
Keyword(s):  
Driving Simulator ◽  
Acute Stress ◽  
Clinical Performance ◽  
Seat Belt ◽  
Task Load ◽  
Stress Levels ◽  
Before And After ◽  
Negative Effect ◽  
Effects Of Stress ◽  
Nasa Task Load Index

Background: Research has suggested that stress may have a negative effect on paramedics' clinical performance. Stress has also been demonstrated to negatively affect the driving abilities of the general population, increasing the number of driving errors. However, no studies have explored stress and its potential impact on the non-clinical performance of paramedics, particularly their driving abilities. Methods: Paramedic students underwent emergency driving assessment in a driving simulator before and after exposure to a stressful medical scenario. The number and type of errors were documented before and after through the use of both driving simulator software and observation by two members of the research team. The NASA Task Load Index (TLX) was used to record self-reported stress levels. Results: Thirty-six students participated in the study. Following exposure to a stressful medical scenario, paramedic students had no rise in overall error rate, but demonstrated increases in three critical driving errors: namely, failure to wear a seat belt (three baseline versus 10 after stress); failing to stop for red lights or stop signs (seven versus 35); and losing control of the vehicle (two versus 11). Self-reported stress levels also increased after the clinical scenario, particularly in the area of mental (cognitive) demand. Conclusion: Paramedics are routinely exposed to acute stress in their everyday work, and this stress could affect their non-clinical performance. The critical errors committed by participants in the present study closely matched those considered to be contributory factors in many ambulance collisions. These results illustrate the need for further research into the effects of stress on non-clinical performance in general, and highlight the potential need to consider additional driver training and stress management education to mitigate the frequency and severity of driving errors among paramedics.

Measuring Sustained Attention and Perceived Workload

2017 ◽  
Vol 59 (1) ◽  
pp. 76-90
Author(s):  
Cynthia Laurie-Rose ◽  
Lori M. Curtindale ◽  
Meredith Frey
Keyword(s):  
Vigilance Task ◽  
Assessment Tools ◽  
Spatial Uncertainty ◽  
Perceptual Sensitivity ◽  
Lowercase Letter ◽  
Task Load ◽  
Performance Differences ◽  
Latency Variability ◽  
Perceived Workload ◽  
Nasa Task Load Index

Objective: We examined the effects of spatial uncertainty, field dependence/independence (FD/I), and sex on vigilance performance and perceived workload in elementary school children. Background: Building on previous work in which children demonstrated their ability to evaluate workload, we tested whether spatial-uncertainty manipulations in a vigilance task would elicit in children the same deleterious effects on performance and workload as it does with adults. We also examined individual difference effects associated with FD/I and sex to determine their influence on both performance and workload. Method: In the low-uncertainty task, stimuli appeared in the center of the computer screen; in the high-uncertainty task, they appeared in one of the four quadrants of the screen. Neutral events consisted of uppercase letter strings. Critical signals consisted of a single lowercase letter among uppercase letters. Following each vigil, children completed a workload assessment via a modified version of the NASA Task Load Index. Results: Children showed lower perceptual sensitivity, greater response latency variability (RTSD), and a higher response criterion in the uncertain display condition. Workload scores reflected these performance differences. Field-dependent children showed lower perceptual sensitivity and greater RTSD than did field-independent children. The two groups exhibited differing workload profiles. Despite no objective performance differences, boys reported greater workload than girls. Conclusion: The scale demonstrated sensitivity and diagnosticity with regard to both the task variable and individual differences. Application: These findings contribute to the emerging field of “educational ergonomics” and indicate that appropriate assessment tools might identify children who are experiencing increased workload.

Weekly Exercise Consistently Reinstates Positive Mood

1998 ◽  
Vol 3 (4) ◽  
pp. 271-280 ◽  
Author(s):  
Hannah Steinberg ◽  
Briony R. Nicholls ◽  
Elizabeth A. Sykes ◽  
N. LeBoutillier ◽  
Nerina Ramlakhan ◽  
...  
Keyword(s):  
Physical Exercise ◽  
Negative Mood ◽  
Real Life ◽  
Positive Mood ◽  
Field Investigation ◽  
Single Bout ◽  
Before And After ◽  
Exercise Class ◽  
Negative Feelings ◽  
Over Time

Mood improvement immediately after a single bout of exercise is well documented, but less is known about successive and longer term effects. In a “real-life” field investigation, four kinds of exercise class (Beginners, Advanced, Body Funk and Callanetics) met once a week for up to 7 weeks. Before and after each class the members assessed how they felt by completing a questionnaire listing equal numbers of “positive” and “negative” mood words. Subjects who had attended at least five times were included in the analysis, which led to groups consisting of 18, 20, 16, and 16 subjects, respectively. All four kinds of exercise significantly increased positive and decreased negative feelings, and this result was surprisingly consistent in successive weeks. However, exercise seemed to have a much greater effect on positive than on negative moods. The favorable moods induced by each class seemed to have worn off by the following week, to be reinstated by the class itself. In the Callanetics class, positive mood also improved significantly over time. The Callanetics class involved “slower,” more demanding exercises, not always done to music. The Callanetics and Advanced classes also showed significantly greater preexercise negative moods in the first three sessions. However, these differences disappeared following exercise. Possibly, these two groups had become more “tolerant” to the mood-enhancing effects of physical exercise; this may be in part have been due to “exercise addiction.”

UK Fiscal Squeezes over a Century

2017 ◽  
Author(s):  
Christopher Hood ◽  
Rozana Himaz
Keyword(s):  
Data Sources ◽  
Fiscal Consolidation ◽  
Financial Outcomes ◽  
Financial Conditions ◽  
Deficit Reduction ◽  
Before And After ◽  
The Uk ◽  
Changes Over Time ◽  
Spending Cuts ◽  
Over Time

This chapter draws on historical statistics reporting financial outcomes for spending, taxation, debt, and deficit for the UK over a century to (a) identify quantitatively and compare the main fiscal squeeze episodes (i.e. major revenue increases, spending cuts, or both) in terms of type (soft squeezes and hard squeezes, spending squeezes, and revenue squeezes), depth, and length; (b) compare these periods of austerity against measures of fiscal consolidation in terms of deficit reduction; and (c) identify economic and financial conditions before and after the various squeezes. It explores the extent to which the identification of squeeze episodes and their classification is sensitive to which thresholds are set and what data sources are used. The chapter identifies major changes over time that emerge from this analysis over the changing depth and types of squeeze.

scholarly journals Land Policy and Food Prices: Evidence from a Land Consolidation Program in Rwanda

2021 ◽  
Vol 19 (1) ◽  
pp. 63-73
Author(s):  
Aimable Nsabimana ◽  
Fidele Niyitanga ◽  
Dave D. Weatherspoon ◽  
Anwar Naseem
Keyword(s):  
Food Prices ◽  
Land Policy ◽  
Land Consolidation ◽  
Easy Access ◽  
Food Crops ◽  
White Potato ◽  
Before And After ◽  
Price Differences ◽  
The Impact ◽  
Over Time

Abstract Rwanda’s “Crop Intensification Program (CIP)” is primarily a land consolidation program aimed at improving agricultural productivity and food security. The program, which began in 2007, focuses on monocropping and commercialization of six priority crops: maize, wheat, rice, white potato, beans, and cassava. CIP has facilitated easy access to improved seed stocks, fertilizer, extension services, and postharvest handling and storage services. Although studies have documented the impact of CIP on changes in farm yield, incomes, and productivity, less is known about its impact on food prices. In this study, we examine the crop-food price differences in intensive monocropped CIP and non-intensive monocropped CIP zones in Rwanda. Specifically, the study evaluates price variations of beans and maize along with complementary food crops in intensive and non-intensive monocropped zones before and after the introduction of the CIP policy. We find that the CIP policy is not associated with differences in CIP crop prices between the intensive and non-intensive monocropped zones. Over time, prices increased for CIP crops but generally, the crop prices in the two zones were cointegrated. Prices for non-CIP crops in the two different zones did show price differentials prior to the implementation of CIP, with the prices in intensive monocropped zones being greater than in the non-intensive monocropped zones. Moreover, the prices in intensive areas are cointegrated with prices in non-intensive areas for maize and beans and these prices are converging. This indicates that farmers who intensively produced one CIP crop were able to go to the market and purchase other food crops and that price differences between zones have decreased over time, potentially making the CIP intensive farmers better off.

scholarly journals Desktop lighting for comfortable use of a computer screen

Work ◽  
2021 ◽  
Vol 68 (s1) ◽  
pp. S209-S221
Author(s):  
Lu Han ◽  
Hechen Zhang ◽  
Zhongxia Xiang ◽  
Jinze Shang ◽  
Shabila Anjani ◽  
...  
Keyword(s):  
High Intensity ◽  
Motion Tracking ◽  
Tracking System ◽  
Computer User ◽  
Eye Tracker ◽  
Computer Screen ◽  
Task Load ◽  
Trunk Movements ◽  
Motion Tracking System ◽  
Nasa Task Load Index

BACKGROUND: The contrast between a bright computer screen and a dark ambient environment may influence comfort of the users, especially on their eyes. OBJECTIVE: The objective of this research is to identify the optimal desktop lighting for the comfortable use of the computer screen in a dark environment. METHODS: An experiment was designed where seven illumination setups were introduced for the users to perform their leisure tasks on a computer screen. Fifteen healthy subjects participated in the experiments. During each session, durations of the eye blinks, fixations and saccades of the user were recorded by an eye tracker. His/her neck and trunk movements were recorded by a motion tracking system as well. The comfort/discomfort questionnaire, localized postural discomfort questionnaire, NASA task load index and computer user questionnaire were used to record the overall comfort/discomfort, the local perceived physical discomfort, the cognitive workload, and general/eye health problems, respectively. RESULTS: Subjective and objective measurement results indicated that users felt more comfortable with high intensity warm lights using a computer screen. We also identified that the eye fixation durations, as well as the scores of two questions in the computer user questionnaire, have significant negative correlations with comfort. On the other side, the durations of blinks and the scores of three questions in the computer user questionnaire, were significantly correlated with discomfort. CONCLUSION: The warm (3000K) and high intensity (1500 lux) light reduced the visual and cognitive fatigue of the user and therefore improve the comfort of the user during the use of a computer screen.

How Collective-Action Failure Shapes Group Heterogeneity and Engagement in Conventional and Radical Action Over Time

2021 ◽  
pp. 095679762097056
Author(s):  
Morgana Lizzio-Wilson ◽  
Emma F. Thomas ◽  
Winnifred R. Louis ◽  
Brittany Wilcockson ◽  
Catherine E. Amiot ◽  
...  
Keyword(s):  
Social Movements ◽  
Collective Action ◽  
Latent Profile Analysis ◽  
Profile Analysis ◽  
Social Identification ◽  
Future Research ◽  
Group Efficacy ◽  
Before And After ◽  
Using Data ◽  
Over Time

Extensive research has identified factors influencing collective-action participation. However, less is known about how collective-action outcomes (i.e., success and failure) shape engagement in social movements over time. Using data collected before and after the 2017 marriage-equality debate in Australia, we conducted a latent profile analysis that indicated that success unified supporters of change ( n = 420), whereas failure created subgroups among opponents ( n = 419), reflecting four divergent responses: disengagement (resigned acceptors), moderate disengagement and continued investment (moderates), and renewed commitment to the cause using similar strategies (stay-the-course opponents) or new strategies (innovators). Resigned acceptors were least inclined to act following failure, whereas innovators were generally more likely to engage in conventional action and justify using radical action relative to the other profiles. These divergent reactions were predicted by differing baseline levels of social identification, group efficacy, and anger. Collective-action outcomes dynamically shape participation in social movements; this is an important direction for future research.

354 Trends in the Drug-Sparing Effects for Benzodiazepines and Prescription Opioids among Insomnia Patients on Suvorexant in the US

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A141-A141
Author(s):  
Hrishikesh Kale ◽  
Rezaul Khandker ◽  
Ruchit Shah ◽  
Marc Botteman ◽  
Weilin Meng ◽  
...  
Keyword(s):  
Interrupted Time Series ◽  
Charlson Comorbidity Index Score ◽  
Prescription Opioid ◽  
Prescription Opioids ◽  
Opioid Use ◽  
Before And After ◽  
Prescription Opioid Use ◽  
Incident Cohort ◽  
Over Time ◽  
Post Period

Abstract Introduction Use of benzodiazepines to treat insomnia has been associated with serious side effects and abuse potential. Insomnia patients are at high risk of opioid abuse and better sleep patterns may help to reduce opioid use. This study examined the trend in the use of benzodiazepines and prescription opioids before and after initiation of suvorexant in insomnia patients. Methods The study analyzed 2015–2019, Optum Clinformatics Data Mart. Insomnia patients, identified using ICD-9/10 codes and prescribed suvorexant were included. The study included incident (newly diagnosed) and prevalent cohorts of insomnia patients. The proportion of patients on benzodiazepines or prescription opioids were calculated for 12 monthly intervals before (pre-period) and after initiation of suvorexant (post-period). Interrupted time series (ITS) analysis was conducted to assess trends for use of benzodiazepine or prescription opioids over time. Results A total of 5,939 patients from the incident insomnia cohort and 18,920 from the prevalent cohort were included. For the incident cohort, mean age was 64.47 (SD: 15.48), 63% were females, 71% had Medicare Advantage coverage, 59% had Charlson comorbidity index score (CCI) ≥ 1, 27% had an anxiety disorder and 16% had substance abuse disorder. Prevalent insomnia cohort was similar but had higher CCI. Results from ITS suggested that at the beginning of the pre-period, 28% of incident insomnia patients used either opioids or benzodiazepines with the rate of use in the pre-period increasing by 0.11% per month. In the post-period, the rate of use decreased by 0.33% per month. About 26% patients used benzodiazepines or opioids at 12-month after suvorexant initiation. In the absence of suvorexant, this proportion would have been 31%. Similar findings were observed for the prevalent insomnia cohort. A larger decrease was observed for opioid use than benzodiazepines. Conclusion The rate of benzodiazepines or prescription opioid use decreased over time after the initiation of suvorexant. Suvorexant has the potential to reduce the use of opioids and benzodiazepines among insomnia patients. Further research is needed to confirm these findings. Support (if any) This study was sponsored by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.

scholarly journals Oral rehydration therapies in Senegal, Mali, and Sierra Leone: a spatial analysis of changes over time and implications for policy

BMC Medicine ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Kirsten E. Wiens ◽  
Lauren E. Schaeffer ◽  
Samba O. Sow ◽  
Babacar Ndoye ◽  
Carrie Jo Cain ◽  
...  
Keyword(s):  
Sierra Leone ◽  
Healthcare Access ◽  
Scale Up ◽  
National Policy ◽  
Geostatistical Model ◽  
Oral Rehydration ◽  
Severe Diarrhea ◽  
Before And After ◽  
Changes Over Time ◽  
Over Time

Abstract Background Oral rehydration solution (ORS) is a simple intervention that can prevent childhood deaths from severe diarrhea and dehydration. In a previous study, we mapped the use of ORS treatment subnationally and found that ORS coverage increased over time, while the use of home-made alternatives or recommended home fluids (RHF) decreased, in many countries. These patterns were particularly striking within Senegal, Mali, and Sierra Leone. It was unclear, however, whether ORS replaced RHF in these locations or if children were left untreated, and if these patterns were associated with health policy changes. Methods We used a Bayesian geostatistical model and data from household surveys to map the percentage of children with diarrhea that received (1) any ORS, (2) only RHF, or (3) no oral rehydration treatment between 2000 and 2018. This approach allowed examination of whether RHF was replaced with ORS before and after interventions, policies, and external events that may have impacted healthcare access. Results We found that RHF was replaced with ORS in most Sierra Leone districts, except those most impacted by the Ebola outbreak. In addition, RHF was replaced in northern but not in southern Mali, and RHF was not replaced anywhere in Senegal. In Senegal, there was no statistical evidence that a national policy promoting ORS use was associated with increases in coverage. In Sierra Leone, ORS coverage increased following a national policy change that abolished health costs for children. Conclusions Children in parts of Mali and Senegal have been left behind during ORS scale-up. Improved messaging on effective diarrhea treatment and/or increased ORS access such as through reducing treatment costs may be needed to prevent child deaths in these areas.

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