Examining Big Brother's Purpose for Using Electronic Performance Monitoring

Science.gov (United States)

Bartels, Lynn K.; Nordstrom, Cynthia R.

2012-01-01

We examined whether the reason offered for electronic performance monitoring (EPM) influenced participants' performance, stress, motivation, and satisfaction. Participants performed a data-entry task in one of five experimental conditions. In one condition, participants were not electronically monitored. In the remaining conditions, participants…

Board Task Performance

DEFF Research Database (Denmark)

Minichilli, Alessandro; Zattoni, Alessandro; Nielsen, Sabina

2012-01-01

identify three board processes as micro-level determinants of board effectiveness. Specifically, we focus on effort norms, cognitive conflicts and the use of knowledge and skills as determinants of board control and advisory task performance. Further, we consider how two different institutional settings....... The findings show that: (i) Board processes have a larger potential than demographic variables to explain board task performance; (ii) board task performance differs significantly between boards operating in different contexts; and (iii) national context moderates the relationships between board processes...... and board task performance....

[Explicit memory for type font of words in source monitoring and recognition tasks].

Science.gov (United States)

Hatanaka, Yoshiko; Fujita, Tetsuya

2004-02-01

We investigated whether people can consciously remember type fonts of words by methods of examining explicit memory; source-monitoring and old/new-recognition. We set matched, non-matched, and non-studied conditions between the study and the test words using two kinds of type fonts; Gothic and MARU. After studying words in one way of encoding, semantic or physical, subjects in a source-monitoring task made a three way discrimination between new words, Gothic words, and MARU words (Exp. 1). Subjects in an old/new-recognition task indicated whether test words were previously presented or not (Exp. 2). We compared the source judgments with old/new recognition data. As a result, these data showed conscious recollection for type font of words on the source monitoring task and dissociation between source monitoring and old/new recognition performance.

Effects of cues in a binary categorization task on dual-task performance, mental workload, and effort.

Science.gov (United States)

Botzer, Assaf; Meyer, Joachim; Parmet, Yisrael

2016-09-01

Binary cues help operators perform binary categorization tasks, such as monitoring for system failures. They may also allow them to attend to other tasks they concurrently perform. If the time saved by using cues is allocated to other concurrent tasks, users' overall effort may remain unchanged. In 2 experiments, participants performed a simulated quality control task, together with a tracking task. In half the experimental blocks cues were available, and participants could use them in their decisions about the quality of products (intact or faulty). In Experiment 1, the difficulty of tracking was constant, while in Experiment 2, tracking difficulty differed in the 2 halves of the experiment. In both experiments, participants reported on the NASA Task Load Index that cues improved their performance and reduced their frustration. Consequently, their overall score on mental workload (MWL) was lower with cues. They also reported, however, that cues did not reduce their effort. We conclude that cues and other forms of automation may support task performance and reduce overall MWL, but this will not necessarily mean that users will work less hard. Thus, effort and overall MWL should be evaluated separately, if one wants to obtain a full picture of the effects of automation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Circadian Effects on Simple Components of Complex Task Performance

Science.gov (United States)

Clegg, Benjamin A.; Wickens, Christopher D.; Vieane, Alex Z.; Gutzwiller, Robert S.; Sebok, Angelia L.

2015-01-01

The goal of this study was to advance understanding and prediction of the impact of circadian rhythm on aspects of complex task performance during unexpected automation failures, and subsequent fault management. Participants trained on two tasks: a process control simulation, featuring automated support; and a multi-tasking platform. Participants then completed one task in a very early morning (circadian night) session, and the other during a late afternoon (circadian day) session. Small effects of time of day were seen on simple components of task performance, but impacts on more demanding components, such as those that occur following an automation failure, were muted relative to previous studies where circadian rhythm was compounded with sleep deprivation and fatigue. Circadian low participants engaged in compensatory strategies, rather than passively monitoring the automation. The findings and implications are discussed in the context of a model that includes the effects of sleep and fatigue factors.

High-definition television evaluation for remote handling task performance

International Nuclear Information System (INIS)

Fujita, Y.; Omori, E.; Hayashi, S.; Draper, J.V.; Herndon, J.N.

1986-01-01

In a plant that employs remote handling techniques for equipment maintenance, operators perform maintenance tasks primarily by using the information from television systems. The efficiency of the television system has a significant impact on remote maintenance task performance. High-definition television (HDTV) transmits a video image with more than twice the number of horizontal scan lines as standard-resolution television (1125 for HDTV to 525 for standard-resolution NTSC television). The added scan lines dramatically improve the resolution of images on the HDTV monitors. This paper describes experiments designed to evaluate the impact of HDTV on the performance of typical remote tasks. The experiments described in this paper compared the performance of four operators using HDTV with their performance while using other television systems. The experiments included four television systems: (a) high-definition color television, (b) high-definition monochromatic television, (c) standard-resolution monochromatic television, and (d) standard-resolution stereoscopic monochromatic television

Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants

Energy Technology Data Exchange (ETDEWEB)

Kenneth A. Yackly

2005-12-01

The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, was re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for coal/IGCC powerplants. The new program was re-titled ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants''. This final report summarizes the work accomplished from March 1, 2003 to March 31, 2004 on the four original tasks, and the work accomplished from April 1, 2004 to July 30, 2005 on the two re-directed tasks. The program Tasks are summarized below: Task 1--IGCC Environmental Impact on high Temperature Materials: The first task was refocused to address IGCC environmental impacts on high temperature materials used in gas turbines. This task screened material performance and quantified the effects of high temperature erosion and corrosion of hot gas path materials in coal/IGCC applications. The materials of interest included those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: The second task was reduced in scope to demonstrate new technologies to determine the inservice health of advanced technology coal/IGCC powerplants. The task focused on two critical sensing needs for advanced coal/IGCC gas turbines: (1) Fuel Quality Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and detection of fuel impurities that could lead to rapid component degradation. (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware. Task 3--Advanced Methods for Combustion Monitoring and Control: The third task was originally to develop and validate advanced monitoring and control methods for coal/IGCC gas

Reward contingencies and the recalibration of task monitoring and reward systems: a high-density electrical mapping study.

Science.gov (United States)

Morie, K P; De Sanctis, P; Foxe, J J

2014-07-25

Task execution almost always occurs in the context of reward-seeking or punishment-avoiding behavior. As such, ongoing task-monitoring systems are influenced by reward anticipation systems. In turn, when a task has been executed either successfully or unsuccessfully, future iterations of that task will be re-titrated on the basis of the task outcome. Here, we examined the neural underpinnings of the task-monitoring and reward-evaluation systems to better understand how they govern reward-seeking behavior. Twenty-three healthy adult participants performed a task where they accrued points that equated to real world value (gift cards) by responding as rapidly as possible within an allotted timeframe, while success rate was titrated online by changing the duration of the timeframe dependent on participant performance. Informative cues initiated each trial, indicating the probability of potential reward or loss (four levels from very low to very high). We manipulated feedback by first informing participants of task success/failure, after which a second feedback signal indicated actual magnitude of reward/loss. High-density electroencephalography (EEG) recordings allowed for examination of event-related potentials (ERPs) to the informative cues and in turn, to both feedback signals. Distinct ERP components associated with reward cues, task-preparatory and task-monitoring processes, and reward feedback processes were identified. Unsurprisingly, participants displayed increased ERP amplitudes associated with task-preparatory processes following cues that predicted higher chances of reward. They also rapidly updated reward and loss prediction information dependent on task performance after the first feedback signal. Finally, upon reward receipt, initial reward probability was no longer taken into account. Rather, ERP measures suggested that only the magnitude of actual reward or loss was now processed. Reward and task-monitoring processes are clearly dissociable, but

Promising high monetary rewards for future task performance increases intermediate task performance.

Directory of Open Access Journals (Sweden)

Claire M Zedelius

Full Text Available In everyday life contexts and work settings, monetary rewards are often contingent on future performance. Based on research showing that the anticipation of rewards causes improved task performance through enhanced task preparation, the present study tested the hypothesis that the promise of monetary rewards for future performance would not only increase future performance, but also performance on an unrewarded intermediate task. Participants performed an auditory Simon task in which they responded to two consecutive tones. While participants could earn high vs. low monetary rewards for fast responses to every second tone, their responses to the first tone were not rewarded. Moreover, we compared performance under conditions in which reward information could prompt strategic performance adjustments (i.e., when reward information was presented for a relatively long duration to conditions preventing strategic performance adjustments (i.e., when reward information was presented very briefly. Results showed that high (vs. low rewards sped up both rewarded and intermediate, unrewarded responses, and the effect was independent of the duration of reward presentation. Moreover, long presentation led to a speed-accuracy trade-off for both rewarded and unrewarded tones, whereas short presentation sped up responses to rewarded and unrewarded tones without this trade-off. These results suggest that high rewards for future performance boost intermediate performance due to enhanced task preparation, and they do so regardless whether people respond to rewards in a strategic or non-strategic manner.

Promising high monetary rewards for future task performance increases intermediate task performance.

Science.gov (United States)

Zedelius, Claire M; Veling, Harm; Bijleveld, Erik; Aarts, Henk

2012-01-01

In everyday life contexts and work settings, monetary rewards are often contingent on future performance. Based on research showing that the anticipation of rewards causes improved task performance through enhanced task preparation, the present study tested the hypothesis that the promise of monetary rewards for future performance would not only increase future performance, but also performance on an unrewarded intermediate task. Participants performed an auditory Simon task in which they responded to two consecutive tones. While participants could earn high vs. low monetary rewards for fast responses to every second tone, their responses to the first tone were not rewarded. Moreover, we compared performance under conditions in which reward information could prompt strategic performance adjustments (i.e., when reward information was presented for a relatively long duration) to conditions preventing strategic performance adjustments (i.e., when reward information was presented very briefly). Results showed that high (vs. low) rewards sped up both rewarded and intermediate, unrewarded responses, and the effect was independent of the duration of reward presentation. Moreover, long presentation led to a speed-accuracy trade-off for both rewarded and unrewarded tones, whereas short presentation sped up responses to rewarded and unrewarded tones without this trade-off. These results suggest that high rewards for future performance boost intermediate performance due to enhanced task preparation, and they do so regardless whether people respond to rewards in a strategic or non-strategic manner.

Task Monotony and Performance Efficacy of Mentally Retarded Young Adults.

Science.gov (United States)

Locke, Bill J.; And Others

1982-01-01

Thirty-six mildly mentally retarded young adults were exposed to one of three training arrangements for vigilance performance, a monitoring task that some professionals consider uniquely appropriate for such persons because they are assumed to be less susceptible to boredom. (Author)

Inaccurate Metacognitive Monitoring and Its Effects on Metacognitive Control and Task Outcomes in Self-Regulated L2 Learning

Science.gov (United States)

Ranalli, Jim

2018-01-01

Accurate metacognitive monitoring of one's own knowledge or performance is a precondition for self-regulated learning; monitoring informs metacognitive control, which in turn affects task outcomes. Studies of monitoring accuracy and its connection to knowledge and performance are common in psychology and educational research but rare in instructed…

Working Memory Training Improves Dual-Task Performance on Motor Tasks.

Science.gov (United States)

Kimura, Takehide; Kaneko, Fuminari; Nagahata, Keita; Shibata, Eriko; Aoki, Nobuhiro

2017-01-01

The authors investigated whether working memory training improves motor-motor dual-task performance consisted of upper and lower limb tasks. The upper limb task was a simple reaction task and the lower limb task was an isometric knee extension task. 45 participants (age = 21.8 ± 1.6 years) were classified into a working memory training group (WM-TRG), dual-task training group, or control group. The training duration was 2 weeks (15 min, 4 times/week). Our results indicated that working memory capacity increased significantly only in the WM-TRG. Dual-task performance improved in the WM-TRG and dual-task training group. Our study provides the novel insight that working memory training improves dual-task performance without specific training on the target motor task.

Computer-Related Task Performance

DEFF Research Database (Denmark)

Longstreet, Phil; Xiao, Xiao; Sarker, Saonee

2016-01-01

The existing information system (IS) literature has acknowledged computer self-efficacy (CSE) as an important factor contributing to enhancements in computer-related task performance. However, the empirical results of CSE on performance have not always been consistent, and increasing an individual......'s CSE is often a cumbersome process. Thus, we introduce the theoretical concept of self-prophecy (SP) and examine how this social influence strategy can be used to improve computer-related task performance. Two experiments are conducted to examine the influence of SP on task performance. Results show...... that SP and CSE interact to influence performance. Implications are then discussed in terms of organizations’ ability to increase performance....

Regulating task-monitoring systems in response to variable reward contingencies and outcomes in cocaine addicts.

Science.gov (United States)

Morie, Kristen P; De Sanctis, Pierfilippo; Garavan, Hugh; Foxe, John J

2016-03-01

We investigated anticipatory and consummatory reward processing in cocaine addiction. In addition, we set out to assess whether task-monitoring systems were appropriately recalibrated in light of variable reward schedules. We also examined neural measures of task-monitoring and reward processing as a function of hedonic tone, since anhedonia is a vulnerability marker for addiction that is obviously germane in the context of reward processing. High-density event-related potentials were recorded while participants performed a speeded response task that systematically varied anticipated probabilities of reward receipt. The paradigm dissociated feedback regarding task success (or failure) from feedback regarding the value of reward (or loss), so that task-monitoring and reward processing could be examined in partial isolation. Twenty-three active cocaine abusers and 23 age-matched healthy controls participated. Cocaine abusers showed amplified anticipatory responses to reward predictive cues, but crucially, these responses were not as strongly modulated by reward probability as in controls. Cocaine users also showed blunted responses to feedback about task success or failure and did not use this information to update predictions about reward. In turn, they showed clearly blunted responses to reward feedback. In controls and users, measures of anhedonia were associated with reward motivation. In cocaine users, anhedonia was also associated with diminished monitoring and reward feedback responses. Findings imply that reward anticipation and monitoring deficiencies in addiction are associated with increased responsiveness to reward cues but impaired ability to predict reward in light of task contingencies, compounded by deficits in responding to actual reward outcomes.

The Attentional Boost Effect: Transient increases in attention to one task enhance performance in a second task.

Science.gov (United States)

Swallow, Khena M; Jiang, Yuhong V

2010-04-01

Recent work on event perception suggests that perceptual processing increases when events change. An important question is how such changes influence the way other information is processed, particularly during dual-task performance. In this study, participants monitored a long series of distractor items for an occasional target as they simultaneously encoded unrelated background scenes. The appearance of an occasional target could have two opposite effects on the secondary task: It could draw attention away from the second task, or, as a change in the ongoing event, it could improve secondary task performance. Results were consistent with the second possibility. Memory for scenes presented simultaneously with the targets was better than memory for scenes that preceded or followed the targets. This effect was observed when the primary detection task involved visual feature oddball detection, auditory oddball detection, and visual color-shape conjunction detection. It was eliminated when the detection task was omitted, and when it required an arbitrary response mapping. The appearance of occasional, task-relevant events appears to trigger a temporal orienting response that facilitates processing of concurrently attended information (Attentional Boost Effect). Copyright 2009 Elsevier B.V. All rights reserved.

Can verbal instruction enhance the recall of an everyday task and promote error-monitoring in people with dementia of the Alzheimer-type?

Science.gov (United States)

Balouch, Sara; Rusted, Jennifer M

2017-03-01

People with dementia of the Alzheimer-type (DAT) have difficulties with performing everyday tasks, and error awareness is poor. Here we investigate whether recall of actions and error monitoring in everyday task performance improved when they instructed another person on how to make tea. In this situation, both visual and motor cues are present, and attention is sustained by the requirement to keep instructing. The data were drawn from a longitudinal study recording performance in four participants with DAT, filmed regularly for five years in their own homes, completing three tea-making conditions: performed-recall (they made tea themselves); instructed-recall (they instructed the experimenter on how to make tea); and verbal-recall (they described how to make tea). Accomplishment scores (percentage of task they correctly recalled), errors and error-monitoring were coded. Task accomplishment was comparable in the performed-recall and instructed-recall conditions, but both were significantly better than task accomplishment in the verbal-recall condition. Third person instruction did not improve error-monitoring. This study has implications for everyday task rehabilitation for people with DAT.

Runtime Performance Monitoring Tool for RTEMS System Software

Science.gov (United States)

Cho, B.; Kim, S.; Park, H.; Kim, H.; Choi, J.; Chae, D.; Lee, J.

2007-08-01

RTEMS is a commercial-grade real-time operating system that supports multi-processor computers. However, there are not many development tools for RTEMS. In this paper, we report new RTEMS-based runtime performance monitoring tool. We have implemented a light weight runtime monitoring task with an extension to the RTEMS APIs. Using our tool, software developers can verify various performance- related parameters during runtime. Our tool can be used during software development phase and in-orbit operation as well. Our implemented target agent is light weight and has small overhead using SpaceWire interface. Efforts to reduce overhead and to add other monitoring parameters are currently under research.

Sustained Attention in Auditory and Visual Monitoring Tasks: Evaluation of the Administration of a Rest Break or Exogenous Vibrotactile Signals.

Science.gov (United States)

Arrabito, G Robert; Ho, Geoffrey; Aghaei, Behzad; Burns, Catherine; Hou, Ming

2015-12-01

Performance and mental workload were observed for the administration of a rest break or exogenous vibrotactile signals in auditory and visual monitoring tasks. Sustained attention is mentally demanding. Techniques are required to improve observer performance in vigilance tasks. Participants (N = 150) monitored an auditory or a visual display for changes in signal duration in a 40-min watch. During the watch, participants were administered a rest break or exogenous vibrotactile signals. Detection accuracy was significantly greater in the auditory than in the visual modality. A short rest break restored detection accuracy in both sensory modalities following deterioration in performance. Participants experienced significantly lower mental workload when monitoring auditory than visual signals, and a rest break significantly reduced mental workload in both sensory modalities. Exogenous vibrotactile signals had no beneficial effects on performance, or mental workload. A rest break can restore performance in auditory and visual vigilance tasks. Although sensory differences in vigilance tasks have been studied, this study is the initial effort to investigate the effects of a rest break countermeasure in both auditory and visual vigilance tasks, and it is also the initial effort to explore the effects of the intervention of a rest break on the perceived mental workload of auditory and visual vigilance tasks. Further research is warranted to determine exact characteristics of effective exogenous vibrotactile signals in vigilance tasks. Potential applications of this research include procedures for decreasing the temporal decline in observer performance and the high mental workload imposed by vigilance tasks. © 2015, Her Majesty the Queen in Right of Canada, as represented by the Minister of National Defence.

Pre-task music improves swimming performance.

Science.gov (United States)

Smirmaul, B P; Dos Santos, R V; Da Silva Neto, L V

2015-12-01

The purpose of this study was to investigate the effects of pre-task music on swimming performance and other psychological variables. A randomized counterbalanced within-subjects (experimental and control condition) design was employed. Eighteen regional level male swimmers performed two 200-m freestyle swimming time trials. Participants were exposed to either 5 minutes of self-selected music (pre-task music condition) or 5 minutes of silence (control condition) and, after 1 minute, performed the swimming task. Swimming time was significantly shorter (-1.44%) in the pre-task music condition. Listening to pre-task music increased motivation to perform the swimming task, while arousal remained unchanged. While fatigue increased after the swimming task in both conditions, vigor, ratings of perceived exertion and affective valence were unaltered. It is concluded, for the first time, that pre-task music improves swimming performance.

Task 1. Monitoring real time materials degradation. NRC extended In-situ and real-time Monitoring

Energy Technology Data Exchange (ETDEWEB)

Bakhtiari, Sasan [Argonne National Lab. (ANL), Argonne, IL (United States)

2012-03-01

The overall objective of this project was to perform a scoping study to identify, in concert with the nuclear industry, those sensors and techniques that have the most promising commercial viability and fill a critical inspection or monitoring need. Candidates to be considered include sensors to monitor real-time material degradation, characterize residual stress, monitor and inspect component fabrication, assess radionuclide and associated chemical species concentrations in ground water and soil, characterize fuel properties, and monitor severe accident conditions. Under Task 1—Monitoring Real-Time Materials Degradation—scoping studies were conducted to assess the feasibility of potential inspection and monitoring technologies (i.e., a combination of sensors, advanced signal processing techniques, and data analysis methods) that could be utilized in LWR and/or advanced reactor applications for continuous monitoring of degradation in-situ. The goal was to identify those techniques that appear to be the most promising, i.e., those that are closest to being both technically and commercially viable and that the nuclear industry is most likely to pursue. Current limitations and associated issues that must be overcome before commercial application of certain techniques have also been addressed.

Subjective and objective quantification of physician's workload and performance during radiation therapy planning tasks.

Science.gov (United States)

Mazur, Lukasz M; Mosaly, Prithima R; Hoyle, Lesley M; Jones, Ellen L; Marks, Lawrence B

2013-01-01

To quantify, and compare, workload for several common physician-based treatment planning tasks using objective and subjective measures of workload. To assess the relationship between workload and performance to define workload levels where performance could be expected to decline. Nine physicians performed the same 3 tasks on each of 2 cases ("easy" vs "hard"). Workload was assessed objectively throughout the tasks (via monitoring of pupil size and blink rate), and subjectively at the end of each case (via National Aeronautics and Space Administration Task Load Index; NASA-TLX). NASA-TLX assesses the 6 dimensions (mental, physical, and temporal demands, frustration, effort, and performance); scores > or ≈ 50 are associated with reduced performance in other industries. Performance was measured using participants' stated willingness to approve the treatment plan. Differences in subjective and objective workload between cases, tasks, and experience were assessed using analysis of variance (ANOVA). The correlation between subjective and objective workload measures were assessed via the Pearson correlation test. The relationships between workload and performance measures were assessed using the t test. Eighteen case-wise and 54 task-wise assessments were obtained. Subjective NASA-TLX scores (P .1), were significantly lower for the easy vs hard case. Most correlations between the subjective and objective measures were not significant, except between average blink rate and NASA-TLX scores (r = -0.34, P = .02), for task-wise assessments. Performance appeared to decline at NASA-TLX scores of ≥55. The NASA-TLX may provide a reasonable method to quantify subjective workload for broad activities, and objective physiologic eye-based measures may be useful to monitor workload for more granular tasks within activities. The subjective and objective measures, as herein quantified, do not necessarily track each other, and more work is needed to assess their utilities. From a

Monitoring cognitive and emotional processes through pupil and cardiac response during dynamic versus logical task.

Science.gov (United States)

Causse, Mickaël; Sénard, Jean-Michel; Démonet, Jean François; Pastor, Josette

2010-06-01

The paper deals with the links between physiological measurements and cognitive and emotional functioning. As long as the operator is a key agent in charge of complex systems, the definition of metrics able to predict his performance is a great challenge. The measurement of the physiological state is a very promising way but a very acute comprehension is required; in particular few studies compare autonomous nervous system reactivity according to specific cognitive processes during task performance and task related psychological stress is often ignored. We compared physiological parameters recorded on 24 healthy subjects facing two neuropsychological tasks: a dynamic task that require problem solving in a world that continually evolves over time and a logical task representative of cognitive processes performed by operators facing everyday problem solving. Results showed that the mean pupil diameter change was higher during the dynamic task; conversely, the heart rate was more elevated during the logical task. Finally, the systolic blood pressure seemed to be strongly sensitive to psychological stress. A better taking into account of the precise influence of a given cognitive activity and both workload and related task-induced psychological stress during task performance is a promising way to better monitor operators in complex working situations to detect mental overload or pejorative stress factor of error.

Performance Enhancements Under Dual-task Conditions

Science.gov (United States)

Kramer, A. F.; Wickens, C. D.; Donchin, E.

1984-01-01

Research on dual-task performance has been concerned with delineating the antecedent conditions which lead to dual-task decrements. Capacity models of attention, which propose that a hypothetical resource structure underlies performance, have been employed as predictive devices. These models predict that tasks which require different processing resources can be more successfully time shared than tasks which require common resources. The conditions under which such dual-task integrality can be fostered were assessed in a study in which three factors likely to influence the integrality between tasks were manipulated: inter-task redundancy, the physical proximity of tasks and the task relevant objects. Twelve subjects participated in three experimental sessions in which they performed both single and dual-tasks. The primary task was a pursuit step tracking task. The secondary tasks required the discrimination between different intensities or different spatial positions of a stimulus. The results are discussed in terms of a model of dual-task integrality.

Auditory N1 reveals planning and monitoring processes during music performance.

Science.gov (United States)

Mathias, Brian; Gehring, William J; Palmer, Caroline

2017-02-01

The current study investigated the relationship between planning processes and feedback monitoring during music performance, a complex task in which performers prepare upcoming events while monitoring their sensory outcomes. Theories of action planning in auditory-motor production tasks propose that the planning of future events co-occurs with the perception of auditory feedback. This study investigated the neural correlates of planning and feedback monitoring by manipulating the contents of auditory feedback during music performance. Pianists memorized and performed melodies at a cued tempo in a synchronization-continuation task while the EEG was recorded. During performance, auditory feedback associated with single melody tones was occasionally substituted with tones corresponding to future (next), present (current), or past (previous) melody tones. Only future-oriented altered feedback disrupted behavior: Future-oriented feedback caused pianists to slow down on the subsequent tone more than past-oriented feedback, and amplitudes of the auditory N1 potential elicited by the tone immediately following the altered feedback were larger for future-oriented than for past-oriented or noncontextual (unrelated) altered feedback; larger N1 amplitudes were associated with greater slowing following altered feedback in the future condition only. Feedback-related negativities were elicited in all altered feedback conditions. In sum, behavioral and neural evidence suggests that future-oriented feedback disrupts performance more than past-oriented feedback, consistent with planning theories that posit similarity-based interference between feedback and planning contents. Neural sensory processing of auditory feedback, reflected in the N1 ERP, may serve as a marker for temporal disruption caused by altered auditory feedback in auditory-motor production tasks. © 2016 Society for Psychophysiological Research.

The flexible engagement of monitoring processes in non-focal and focal prospective memory tasks with salient cues.

Science.gov (United States)

Hefer, Carmen; Cohen, Anna-Lisa; Jaudas, Alexander; Dreisbach, Gesine

2017-09-01

Prospective memory (PM) refers to the ability to remember to perform a delayed intention. Here, we aimed to investigate the ability to suspend such an intention and thus to confirm previous findings (Cohen, Gordon, Jaudas, Hefer, & Dreisbach, 2016) demonstrating the ability to flexibly engage in monitoring processes. In the current study, we presented a perceptually salient PM cue (bold and red) to rule out that previous findings were limited to non-salient and, thus, easy to ignore PM cues. Moreover, we used both a non-focal (Experiment 1) and a focal PM (Experiment 2) cue. In both Experiments, three groups of participants performed an Eriksen flanker task as an ongoing task with an embedded PM task (they had to remember to press the F1 key if a pre-specified cue appeared). Participants were assigned to either a control condition (performed solely the flanker task), a standard PM condition (performed the flanker task along with the PM task), or a PM delayed condition (performed the flanker task but were instructed to postpone their PM task intention). The results of Experiment 1 with the non-focal PM cue closely replicated those of Cohen et al. (2016) and confirmed that participants were able to successfully postpone the PM cue intention without additional costs even when the PM cue was a perceptually salient one. However, when the PM cue was focal (Experiment 2), it was much more difficult for participants to ignore it as evidenced by commission errors and slower latencies on PM cue trials. In sum, results showed that the focality of the PM cue plays a more crucial role in the flexibility of the monitoring process whereas the saliency of the PM cue does not. Copyright © 2017 Elsevier B.V. All rights reserved.

Isolating the Neural Mechanisms of Interference During Continuous Multisensory Dual-task Performance

Science.gov (United States)

2014-01-01

of multitasking impairments have focused on the performance of two tasks presented in close temporal proximity on discrete trials; however, such...simultaneously and continuously monitor both auditory communications from pilots and visual radar displays. Drivers may choose to hold a cell phone

Vigilance impossible: Diligence, distraction, and daydreaming all lead to failures in a practical monitoring task.

Science.gov (United States)

Casner, Stephen M; Schooler, Jonathan W

2015-09-01

In laboratory studies of vigilance, participants watch for unusual events in a "sit and stare" fashion as their performance typically declines over time. But watch keepers in practical settings seldom approach monitoring in such simplistic ways and controlled environments. We observed airline pilots performing routine monitoring duties in the cockpit. Unlike laboratory studies, pilots' monitoring did not deteriorate amidst prolonged vigils. Monitoring was frequently interrupted by other pop-up tasks and misses followed. However, when free from these distractions, pilots reported copious mind wandering. Pilots often confined their mind wandering to times in which their monitoring performance would not conspicuously suffer. But when no convenient times were available, pilots mind wandered anyway and misses ensued. Real-world monitors may be caught between a continuous vigilance approach that is doomed to fail, a dynamic environment that cannot be fully controlled, and what may be an irresistible urge to let one's thoughts drift. Published by Elsevier Inc.

Alterations in Resting-State Activity Relate to Performance in a Verbal Recognition Task

Science.gov (United States)

López Zunini, Rocío A.; Thivierge, Jean-Philippe; Kousaie, Shanna; Sheppard, Christine; Taler, Vanessa

2013-01-01

In the brain, resting-state activity refers to non-random patterns of intrinsic activity occurring when participants are not actively engaged in a task. We monitored resting-state activity using electroencephalogram (EEG) both before and after a verbal recognition task. We show a strong positive correlation between accuracy in verbal recognition and pre-task resting-state alpha power at posterior sites. We further characterized this effect by examining resting-state post-task activity. We found marked alterations in resting-state alpha power when comparing pre- and post-task periods, with more pronounced alterations in participants that attained higher task accuracy. These findings support a dynamical view of cognitive processes where patterns of ongoing brain activity can facilitate –or interfere– with optimal task performance. PMID:23785436

Response-cue interval effects in extended-runs task switching: memory, or monitoring?

Science.gov (United States)

Altmann, Erik M

2017-09-26

This study investigated effects of manipulating the response-cue interval (RCI) in the extended-runs task-switching procedure. In this procedure, a task cue is presented at the start of a run of trials and then withdrawn, such that the task has to be stored in memory to guide performance until the next task cue is presented. The effects of the RCI manipulation were not as predicted by an existing model of memory processes in task switching (Altmann and Gray, Psychol Rev 115:602-639, 2008), suggesting that either the model is incorrect or the RCI manipulation did not have the intended effect. The manipulation did produce a theoretically meaningful pattern, in the form of a main effect on response time that was not accompanied by a similar effect on the error rate. This pattern, which replicated across two experiments, is interpreted here in terms of a process that monitors for the next task cue, with a longer RCI acting as a stronger signal that a cue is about to appear. The results have implications for the human factors of dynamic task environments in which critical events occur unpredictably.

The Effect of Retention Interval Task Difficulty on Young Children's Prospective Memory: Testing the Intention Monitoring Hypothesis

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Mahy, Caitlin E. V.; Moses, Louis J.

2015-01-01

The current study examined the impact of retention interval task difficulty on 4- and 5-year-olds' prospective memory (PM) to test the hypothesis that children periodically monitor their intentions during the retention interval and that disrupting this monitoring may result in poorer PM performance. In addition, relations among PM, working memory,…

Performance Monitoring in Children Following Traumatic Brain Injury Compared to Typically Developing Children

Directory of Open Access Journals (Sweden)

Amy A. Wilkinson PhD

2017-10-01

Full Text Available Children with traumatic brain injury are reported to have deficits in performance monitoring, but the mechanisms underlying these deficits are not well understood. Four performance monitoring hypotheses were explored by comparing how 28 children with traumatic brain injury and 28 typically developing controls (matched by age and sex performed on the stop-signal task. Control children slowed significantly more following incorrect than correct stop-signal trials, fitting the error monitoring hypothesis. In contrast, the traumatic brain injury group showed no performance monitoring difference with trial types, but significant group differences did not emerge, suggesting that children with traumatic brain injury may not perform the same way as controls.

The Task Is Not Enough: Processing Approaches to Task-Based Performance

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Skehan, Peter; Xiaoyue, Bei; Qian, Li; Wang, Zhan

2012-01-01

This article reports on three research studies, all of which concern second language task performance. The first focuses on planning, and compares on-line and strategic planning as well as task repetition. The second study examines the role of familiarity on task performance, and compares this with conventional strategic planning. The third study…

Dashboard Task Monitor for Managing ATLAS User Analysis on the Grid

Science.gov (United States)

Sargsyan, L.; Andreeva, J.; Jha, M.; Karavakis, E.; Kokoszkiewicz, L.; Saiz, P.; Schovancova, J.; Tuckett, D.; Atlas Collaboration

2014-06-01

The organization of the distributed user analysis on the Worldwide LHC Computing Grid (WLCG) infrastructure is one of the most challenging tasks among the computing activities at the Large Hadron Collider. The Experiment Dashboard offers a solution that not only monitors but also manages (kill, resubmit) user tasks and jobs via a web interface. The ATLAS Dashboard Task Monitor provides analysis users with a tool that is independent of the operating system and Grid environment. This contribution describes the functionality of the application and its implementation details, in particular authentication, authorization and audit of the management operations.

Dashboard task monitor for managing ATLAS user analysis on the grid

International Nuclear Information System (INIS)

Sargsyan, L; Andreeva, J; Karavakis, E; Saiz, P; Tuckett, D; Jha, M; Kokoszkiewicz, L; Schovancova, J

2014-01-01

The organization of the distributed user analysis on the Worldwide LHC Computing Grid (WLCG) infrastructure is one of the most challenging tasks among the computing activities at the Large Hadron Collider. The Experiment Dashboard offers a solution that not only monitors but also manages (kill, resubmit) user tasks and jobs via a web interface. The ATLAS Dashboard Task Monitor provides analysis users with a tool that is independent of the operating system and Grid environment. This contribution describes the functionality of the application and its implementation details, in particular authentication, authorization and audit of the management operations.

Predictive performance models and multiple task performance

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Wickens, Christopher D.; Larish, Inge; Contorer, Aaron

1989-01-01

Five models that predict how performance of multiple tasks will interact in complex task scenarios are discussed. The models are shown in terms of the assumptions they make about human operator divided attention. The different assumptions about attention are then empirically validated in a multitask helicopter flight simulation. It is concluded from this simulation that the most important assumption relates to the coding of demand level of different component tasks.

Planning and task management in Parkinson's disease: differential emphasis in dual-task performance.

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Bialystok, Ellen; Craik, Fergus I M; Stefurak, Taresa

2008-03-01

Seventeen patients diagnosed with Parkinson's disease completed a complex computer-based task that involved planning and management while also performing an attention-demanding secondary task. The tasks were performed concurrently, but it was necessary to switch from one to the other. Performance was compared to a group of healthy age-matched control participants and a group of young participants. Parkinson's patients performed better than the age-matched controls on almost all measures and as well as the young controls in many cases. However, the Parkinson's patients achieved this by paying relatively less attention to the secondary task and focusing attention more on the primary task. Thus, Parkinson's patients can apparently improve their performance on some aspects of a multidimensional task by simplifying task demands. This benefit may occur as a consequence of their inflexible exaggerated attention to some aspects of a complex task to the relative neglect of other aspects.

How Stimulus and Task Complexity Affect Monitoring in High-Functioning Adults with Autism Spectrum Disorder

NARCIS (Netherlands)

Koolen, S.; Vissers, C.T.W.M.; Egger, J.I.M.; Verhoeven, L.T.W.

2014-01-01

The present study examined whether individuals with autism spectrum disorder (ASD) are able to update and monitor working memory representations of visual input, and whether performance is influenced by stimulus and task complexity. 15 high-functioning adults with ASD and 15 controls were asked to

Task complexity, student perceptions of vocabulary learning in EFL, and task performance.

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Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2013-03-01

The study deepened our understanding of how students' self-efficacy beliefs contribute to the context of teaching English as a foreign language in the framework of cognitive mediational paradigm at a fine-tuned task-specific level. The aim was to examine the relationship among task complexity, self-efficacy beliefs, domain-related prior knowledge, learning strategy use, and task performance as they were applied to English vocabulary learning from reading tasks. Participants were 120 second-year university students (mean age 21) from a Chinese university. This experiment had two conditions (simple/complex). A vocabulary level test was first conducted to measure participants' prior knowledge of English vocabulary. Participants were then randomly assigned to one of the learning tasks. Participants were administered task booklets together with the self-efficacy scales, measures of learning strategy use, and post-tests. Data obtained were submitted to multivariate analysis of variance (MANOVA) and path analysis. Results from the MANOVA model showed a significant effect of vocabulary level on self-efficacy beliefs, learning strategy use, and task performance. Task complexity showed no significant effect; however, an interaction effect between vocabulary level and task complexity emerged. Results from the path analysis showed self-efficacy beliefs had an indirect effect on performance. Our results highlighted the mediating role of self-efficacy beliefs and learning strategy use. Our findings indicate that students' prior knowledge plays a crucial role on both self-efficacy beliefs and task performance, and the predictive power of self-efficacy on task performance may lie in its association with learning strategy use. © 2011 The British Psychological Society.

Cerebral blood flow, fatigue, mental effort, and task performance in offices with two different pollution loads

DEFF Research Database (Denmark)

Nishihara, Naoe; Wargocki, Pawel; Tanabe, Shin-ichi

2014-01-01

The effects of indoor air quality on symptoms, perceptions, task performance, cerebral blood flow, fatigue, and mental effort of individuals working in an office were investigated. Twenty-four right-handed Danish female subjects in an office were exposed in groups of two at a time to two air...... pollution levels created by placing or removing a pollution source (i.e. a used carpet) behind a screen. During the exposure, the subjects performed four different office tasks presented on a computer monitor. The tasks were performed at two paces: normal and maximum. When the pollution source was present...... any effects caused by modifying pollution exposure, they were well correlated with increased mental effort when the tasks were performed at maximum pace and subjectively reported fatigue, which increased during the course of exposure, respectively....

Measuring cognitive load: performance, mental effort and simulation task complexity.

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Haji, Faizal A; Rojas, David; Childs, Ruth; de Ribaupierre, Sandrine; Dubrowski, Adam

2015-08-01

Interest in applying cognitive load theory in health care simulation is growing. This line of inquiry requires measures that are sensitive to changes in cognitive load arising from different instructional designs. Recently, mental effort ratings and secondary task performance have shown promise as measures of cognitive load in health care simulation. We investigate the sensitivity of these measures to predicted differences in intrinsic load arising from variations in task complexity and learner expertise during simulation-based surgical skills training. We randomly assigned 28 novice medical students to simulation training on a simple or complex surgical knot-tying task. Participants completed 13 practice trials, interspersed with computer-based video instruction. On trials 1, 5, 9 and 13, knot-tying performance was assessed using time and movement efficiency measures, and cognitive load was assessed using subjective rating of mental effort (SRME) and simple reaction time (SRT) on a vibrotactile stimulus-monitoring secondary task. Significant improvements in knot-tying performance (F(1.04,24.95)  = 41.1, p cognitive load (F(2.3,58.5)  = 57.7, p load among novices engaged in simulation-based learning. These measures can be used to track cognitive load during skills training. Mental effort ratings are also sensitive to small differences in intrinsic load arising from variations in the physical complexity of a simulation task. The complementary nature of these subjective and objective measures suggests their combined use is advantageous in simulation instructional design research. © 2015 John Wiley & Sons Ltd.

Short-term memory and dual task performance

Science.gov (United States)

Regan, J. E.

1982-01-01

Two hypotheses concerning the way in which short-term memory interacts with another task in a dual task situation are considered. It is noted that when two tasks are combined, the activity of controlling and organizing performance on both tasks simultaneously may compete with either task for a resource; this resource may be space in a central mechanism or general processing capacity or it may be some task-specific resource. If a special relationship exists between short-term memory and control, especially if there is an identity relationship between short-term and a central controlling mechanism, then short-term memory performance should show a decrement in a dual task situation. Even if short-term memory does not have any particular identity with a controlling mechanism, but both tasks draw on some common resource or resources, then a tradeoff between the two tasks in allocating resources is possible and could be reflected in performance. The persistent concurrence cost in memory performance in these experiments suggests that short-term memory may have a unique status in the information processing system.

Verbal monitoring in Parkinson’s disease: A comparison between internal and external monitoring

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Mertens, Jolien; Mariën, Peter; Santens, Patrick; Pickut, Barbara A.; Hartsuiker, Robert J.

2017-01-01

Patients with Parkinson’s disease (PD) display a variety of impairments in motor and non-motor language processes; speech is decreased on motor aspects such as amplitude, prosody and speed and on linguistic aspects including grammar and fluency. Here we investigated whether verbal monitoring is impaired and what the relative contributions of the internal and external monitoring route are on verbal monitoring in patients with PD relative to controls. Furthermore, the data were used to investigate whether internal monitoring performance could be predicted by internal speech perception tasks, as perception based monitoring theories assume. Performance of 18 patients with Parkinson’s disease was measured on two cognitive performance tasks and a battery of 11 linguistic tasks, including tasks that measured performance on internal and external monitoring. Results were compared with those of 16 age-matched healthy controls. PD patients and controls generally performed similarly on the linguistic and monitoring measures. However, we observed qualitative differences in the effects of noise masking on monitoring and disfluencies and in the extent to which the linguistic tasks predicted monitoring behavior. We suggest that the patients differ from healthy subjects in their recruitment of monitoring channels. PMID:28832595

The predictive value of general movement tasks in assessing occupational task performance.

Science.gov (United States)

Frost, David M; Beach, Tyson A C; McGill, Stuart M; Callaghan, Jack P

2015-01-01

Within the context of evaluating individuals' movement behavior it is generally assumed that the tasks chosen will predict their competency to perform activities relevant to their occupation. This study sought to examine whether a battery of general tasks could be used to predict the movement patterns employed by firefighters to perform select job-specific skills. Fifty-two firefighters performed a battery of general and occupation-specific tasks that simulated the demands of firefighting. Participants' peak lumbar spine and frontal plane knee motion were compared across tasks. During 85% of all comparisons, the magnitude of spine and knee motion was greater during the general movement tasks than observed during the firefighting skills. Certain features of a worker's movement behavior may be exhibited across a range of tasks. Therefore, provided that a movement screen's tasks expose the motions of relevance for the population being tested, general evaluations could offer valuable insight into workers' movement competency or facilitate an opportunity to establish an evidence-informed intervention.

THE PROBLEMS OF PERFORMANCE MONITORING TO TAKLE THE TASKS OF THE AIRCRAFT CONTINUED AIRWORTHINESS

Directory of Open Access Journals (Sweden)

Yu. M. Chinyuchin

2017-01-01

Full Text Available Improving of the aircraft continued airworthiness system is currently becoming of particular importance applied both to aircraft of domestic and foreign production, used in civil aviation of Russia. This article discusses the background and content of the tasks for long-haul aircraft continued airworthiness, which presents a challenge directly related to the provision of intensive, regular, economically viable, and safe operation of assigned airline fleet. A special place among the problems of continued airworthiness is held by the creation and organization of mechanisms and methods of resource status and age of the assigned airline fleet monitoring to manage its forecasting and timely updates. Not least important among the issues of resource and age structure monitoring to be considered is the need to improve the design of aircraft, taking into account preliminary technical and economic feasibility assessment of its modifications in the interests of the operator. A deep study of the contents of the monitoring allows to develop up-to-date methodological and scientific basis for building an integrated system of aircraft resource management and timing services. This system is developed based on the integrated approach that allows to provide a solution to the entire set of problems presented in this article and faced by professionals and scientists involved in the aircraft maintenance programs development on the stages of their design and manufacturing and long operation of aircraft continued airworthiness.

Development of a Field-Deployable Psychomotor Vigilance Test to Monitor Helicopter Pilot Performance.

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McMahon, Terry W; Newman, David G

2016-04-01

Flying a helicopter is a complex psychomotor skill. Fatigue is a serious threat to operational safety, particularly for sustained helicopter operations involving high levels of cognitive information processing and sustained time on task. As part of ongoing research into this issue, the object of this study was to develop a field-deployable helicopter-specific psychomotor vigilance test (PVT) for the purpose of daily performance monitoring of pilots. The PVT consists of a laptop computer, a hand-operated joystick, and a set of rudder pedals. Screen-based compensatory tracking task software includes a tracking ball (operated by the joystick) which moves randomly in all directions, and a second tracking ball which moves horizontally (operated by the rudder pedals). The 5-min test requires the pilot to keep both tracking balls centered. This helicopter-specific PVT's portability and integrated data acquisition and storage system enables daily field monitoring of the performance of individual helicopter pilots. The inclusion of a simultaneous foot-operated tracking task ensures divided attention for helicopter pilots as the movement of both tracking balls requires simultaneous inputs. This PVT is quick, economical, easy to use, and specific to the operational flying task. It can be used for performance monitoring purposes, and as a general research tool for investigating the psychomotor demands of helicopter operations. While reliability and validity testing is warranted, data acquired from this test could help further our understanding of the effect of various factors (such as fatigue) on helicopter pilot performance, with the potential of contributing to helicopter operational safety.

Single-task and dual-task tandem gait test performance after concussion.

Science.gov (United States)

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2017-07-01

To compare single-task and dual-task tandem gait test performance between athletes after concussion with controls on observer-timed, spatio-temporal, and center-of-mass (COM) balance control measurements. Ten participants (19.0±5.5years) were prospectively identified and completed a tandem gait test protocol within 72h of concussion and again 1 week, 2 weeks, 1 month, and 2 months post-injury. Seven uninjured controls (20.0±4.5years) completed the same protocol in similar time increments. Tandem gait test trials were performed with (dual-task) and without (single-task) concurrently performing a cognitive test as whole-body motion analysis was performed. Outcome variables included test completion time, average tandem gait velocity, cadence, and whole-body COM frontal plane displacement. Concussion participants took significantly longer to complete the dual-task tandem gait test than controls throughout the first 2 weeks post-injury (mean time=16.4 [95% CI: 13.4-19.4] vs. 10.1 [95% CI: 6.4-13.7] seconds; p=0.03). Single-task tandem gait times were significantly lower 72h post-injury (p=0.04). Dual-task cadence was significantly lower for concussion participants than controls (89.5 [95% CI: 68.6-110.4] vs. 127.0 [95% CI: 97.4-156.6] steps/minute; p=0.04). Moderately-high to high correlations between tandem gait test time and whole-body COM medial-lateral displacement were detected at each time point during dual-task gait (r s =0.70-0.93; p=0.03-0.001). Adding a cognitive task during the tandem gait test resulted in longer detectable deficits post-concussion compared to the traditional single-task tandem gait test. As a clinical tool to assess dynamic motor function, tandem gait may assist with return to sport decisions after concussion. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Performance samples on academic tasks : improving prediction of academic performance

NARCIS (Netherlands)

Tanilon, Jenny

2011-01-01

This thesis is about the development and validation of a performance-based test, labeled as Performance Samples on academic tasks in Education and Child Studies (PSEd). PSEd is designed to identify students who are most able to perform the academic tasks involved in an Education and Child Studies

Musical expertise has minimal impact on dual task performance.

Science.gov (United States)

Cocchini, Gianna; Filardi, Maria Serena; Crhonkova, Marcela; Halpern, Andrea R

2017-05-01

Studies investigating effect of practice on dual task performance have yielded conflicting findings, thus supporting different theoretical accounts about the organisation of attentional resources when tasks are performed simultaneously. Because practice has been proven to reduce the demand of attention for the trained task, the impact of long-lasting training on one task is an ideal way to better understand the mechanisms underlying dual task decline in performance. Our study compared performance during dual task execution in expert musicians compared to controls with little if any musical experience. Participants performed a music recognition task and a visuo-spatial task separately (single task) or simultaneously (dual task). Both groups showed a significant but similar performance decline during dual tasks. In addition, the two groups showed a similar decline of dual task performance during encoding and retrieval of the musical information, mainly attributed to a decline in sensitivity. Our results suggest that attention during dual tasks is similarly distributed by expert and non-experts. These findings are in line with previous studies showing a lack of sensitivity to difficulty and lack of practice effect during dual tasks, supporting the idea that different tasks may rely on different and not-sharable attentional resources.

Mood states determine the degree of task shielding in dual-task performance.

Science.gov (United States)

Zwosta, Katharina; Hommel, Bernhard; Goschke, Thomas; Fischer, Rico

2013-01-01

Current models of multitasking assume that dual-task performance and the degree of multitasking are affected by cognitive control strategies. In particular, cognitive control is assumed to regulate the amount of shielding of the prioritised task from crosstalk from the secondary task. We investigated whether and how task shielding is influenced by mood states. Participants were exposed to two short film clips, one inducing high and one inducing low arousal, of either negative or positive content. Negative mood led to stronger shielding of the prioritised task (i.e., less crosstalk) than positive mood, irrespective of arousal. These findings support the assumption that emotional states determine the parameters of cognitive control and play an important role in regulating dual-task performance.

Performance Monitoring in Medication-Naïve Children with Tourette Syndrome

DEFF Research Database (Denmark)

Eichele, Heike; Eichele, Tom; Bjelland, Ingvar

2016-01-01

BACKGROUND: Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder and its impact on cognitive development needs further study. Evidence from neuropsychological, neuroimaging and electrophysiological studies suggests that the decline in tic severity and the ability to suppress tics...... relate to the development of self-regulatory functions in late childhood and adolescence. Hence, tasks measuring performance monitoring might provide insight into the regulation of tics in children with TS. METHOD: Twenty-five children with TS, including 14 with comorbid Attention-deficit/ hyperactivity...... disorder (ADHD), 39 children with ADHD and 35 typically developing children aged 8-12 years were tested with a modified Eriksen-Flanker task during a 34-channel electroencephalography (EEG) recording. Task performance, as well as stimulus-locked and response-locked event-related potentials (ERP) were...

Dividing attention between tasks : Testing whether explicit payoff functions elicit optimal dual-task performance

NARCIS (Netherlands)

Farmer, George D.; Janssen, C.P.|info:eu-repo/dai/nl/412781654; Nguyen, Anh T; Brumby, Duncan P.

2018-01-01

We test people's ability to optimize performance across two concurrent tasks. Participants performed a number entry task while controlling a randomly moving cursor with a joystick. Participants received explicit feedback on their performance on these tasks in the form of a single combined score.

Blinks, saccades, and fixation pauses during vigilance task performance. II., Gender and time of day.

Science.gov (United States)

1996-03-01

As operators are required to spend more time monitoring computer controlled devices in future systems, it is critical to define the task and situational factors (i.e., fatigue) that may impact vigilance and performance. Aspects of the gaze system can...

HwPMI: An Extensible Performance Monitoring Infrastructure for Improving Hardware Design and Productivity on FPGAs

Directory of Open Access Journals (Sweden)

Andrew G. Schmidt

2012-01-01

Full Text Available Designing hardware cores for FPGAs can quickly become a complicated task, difficult even for experienced engineers. With the addition of more sophisticated development tools and maturing high-level language-to-gates techniques, designs can be rapidly assembled; however, when the design is evaluated on the FPGA, the performance may not be what was expected. Therefore, an engineer may need to augment the design to include performance monitors to better understand the bottlenecks in the system or to aid in the debugging of the design. Unfortunately, identifying what to monitor and adding the infrastructure to retrieve the monitored data can be a challenging and time-consuming task. Our work alleviates this effort. We present the Hardware Performance Monitoring Infrastructure (HwPMI, which includes a collection of software tools and hardware cores that can be used to profile the current design, recommend and insert performance monitors directly into the HDL or netlist, and retrieve the monitored data with minimal invasiveness to the design. Three applications are used to demonstrate and evaluate HwPMI’s capabilities. The results are highly encouraging as the infrastructure adds numerous capabilities while requiring minimal effort by the designer and low resource overhead to the existing design.

Effects of age and auditory and visual dual tasks on closed-road driving performance.

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Chaparro, Alex; Wood, Joanne M; Carberry, Trent

2005-08-01

This study investigated how driving performance of young and old participants is affected by visual and auditory secondary tasks on a closed driving course. Twenty-eight participants comprising two age groups (younger, mean age = 27.3 years; older, mean age = 69.2 years) drove around a 5.1-km closed-road circuit under both single and dual task conditions. Measures of driving performance included detection and identification of road signs, detection and avoidance of large low-contrast road hazards, gap judgment, lane keeping, and time to complete the course. The dual task required participants to verbally report the sums of pairs of single-digit numbers presented through either a computer speaker (auditorily) or a dashboard-mounted monitor (visually) while driving. Participants also completed a vision and cognitive screening battery, including LogMAR visual acuity, Pelli-Robson letter contrast sensitivity, the Trails test, and the Digit Symbol Substitution (DSS) test. Drivers reported significantly fewer signs, hit more road hazards, misjudged more gaps, and increased their time to complete the course under the dual task (visual and auditory) conditions compared with the single task condition. The older participants also reported significantly fewer road signs and drove significantly more slowly than the younger participants, and this was exacerbated for the visual dual task condition. The results of the regression analysis revealed that cognitive aging (measured by the DSS and Trails test) rather than chronologic age was a better predictor of the declines seen in driving performance under dual task conditions. An overall z score was calculated, which took into account both driving and the secondary task (summing) performance under the two dual task conditions. Performance was significantly worse for the auditory dual task compared with the visual dual task, and the older participants performed significantly worse than the young subjects. These findings demonstrate

Investigating General Chemistry Students' Metacognitive Monitoring of Their Exam Performance by Measuring Postdiction Accuracies over Time

Science.gov (United States)

Hawker, Morgan J.; Dysleski, Lisa; Rickey, Dawn

2016-01-01

Metacognitive monitoring of one's own understanding plays a key role in learning. An aspect of metacognitive monitoring can be measured by comparing a student's prediction or postdiction of performance (a judgment made before or after completing the relevant task) with the student's actual performance. In this study, we investigated students'…

Task performance in astronomical adaptive optics

Science.gov (United States)

Barrett, Harrison H.; Myers, Kyle J.; Devaney, Nicholas; Dainty, J. C.; Caucci, Luca

2006-06-01

In objective or task-based assessment of image quality, figures of merit are defined by the performance of some specific observer on some task of scientific interest. This methodology is well established in medical imaging but is just beginning to be applied in astronomy. In this paper we survey the theory needed to understand the performance of ideal or ideal-linear (Hotelling) observers on detection tasks with adaptive-optical data. The theory is illustrated by discussing its application to detection of exoplanets from a sequence of short-exposure images.

The effects of stimulus modality and task integrality: Predicting dual-task performance and workload from single-task levels

Science.gov (United States)

Hart, S. G.; Shively, R. J.; Vidulich, M. A.; Miller, R. C.

1986-01-01

The influence of stimulus modality and task difficulty on workload and performance was investigated. The goal was to quantify the cost (in terms of response time and experienced workload) incurred when essentially serial task components shared common elements (e.g., the response to one initiated the other) which could be accomplished in parallel. The experimental tasks were based on the Fittsberg paradigm; the solution to a SternBERG-type memory task determines which of two identical FITTS targets are acquired. Previous research suggested that such functionally integrated dual tasks are performed with substantially less workload and faster response times than would be predicted by suming single-task components when both are presented in the same stimulus modality (visual). The physical integration of task elements was varied (although their functional relationship remained the same) to determine whether dual-task facilitation would persist if task components were presented in different sensory modalities. Again, it was found that the cost of performing the two-stage task was considerably less than the sum of component single-task levels when both were presented visually. Less facilitation was found when task elements were presented in different sensory modalities. These results suggest the importance of distinguishing between concurrent tasks that complete for limited resources from those that beneficially share common resources when selecting the stimulus modalities for information displays.

Reduced Electromyographic Fatigue Threshold after Performing a Cognitive Fatiguing Task.

Science.gov (United States)

Ferris, Justine R; Tomlinson, Mary A; Ward, Tayler N; Pepin, Marie E; Malek, Moh H

2018-02-22

Cognitive fatigue tasks performed prior to exercise may reduce exercise capacity. The electromyographic fatigue threshold (EMGFT) is the highest exercise intensity that can be maintained without significant increase in the EMG amplitude versus time relationship. To date, no studies have examined the effect of cognitive fatigue on the estimation of the EMGFT. The purpose of this study, therefore, was to determine whether or not cognitive fatigue prior to performing exercise reduces the estimated EMGFT. Eight healthy college-aged men were recruited from a university student population and visited the laboratory on multiple occasions. In a randomized order, subjects performed either the cognitive fatigue task (AX Continuous Performance Test; AX-CPT) for 60 min on one visit (experimental condition) or watched a video on trains for 60 min on the other visit (control condition). After each condition, subjects performed the incremental single-leg knee-extensor ergometry test while the EMG amplitude was recorded from the rectus femoris muscle and heart rate was monitored throughout. Thereafter, the EMGFT was calculated for each participant for each visit and compared using paired samples t-test. For exercise outcomes, there were no significant mean differences for maximal power output between the two conditions (control: 51 ± 5 vs. fatigue: 50 ± 3 W), but a significant decrease in EMGFT between the two conditions (control: 31 ± 3 vs. fatigue: 24 ± 2 W; p = 0.013). Moreover, maximal heart rate was significantly different between the two conditions (control: 151 ± 5 vs. fatigue: 132 ± 6; p = 0.027). These results suggest that performing the cognitive fatiguing task reduces the EMGFT with a corresponding reduction in maximal heart rate response.

Event-related potentials and secondary task performance during simulated driving.

Science.gov (United States)

Wester, A E; Böcker, K B E; Volkerts, E R; Verster, J C; Kenemans, J L

2008-01-01

Inattention and distraction account for a substantial number of traffic accidents. Therefore, we examined the impact of secondary task performance (an auditory oddball task) on a primary driving task (lane keeping). Twenty healthy participants performed two 20-min tests in the Divided Attention Steering Simulator (DASS). The visual secondary task of the DASS was replaced by an auditory oddball task to allow recording of brain activity. The driving task and the secondary (distracting) oddball task were presented in isolation and simultaneously, to assess their mutual interference. In addition to performance measures (lane keeping in the primary driving task and reaction speed in the secondary oddball task), brain activity, i.e. event-related potentials (ERPs), was recorded. Performance parameters on the driving test and the secondary oddball task did not differ between performance in isolation and simultaneous performance. However, when both tasks were performed simultaneously, reaction time variability increased in the secondary oddball task. Analysis of brain activity indicated that ERP amplitude (P3a amplitude) related to the secondary task, was significantly reduced when the task was performed simultaneously with the driving test. This study shows that when performing a simple secondary task during driving, performance of the driving task and this secondary task are both unaffected. However, analysis of brain activity shows reduced cortical processing of irrelevant, potentially distracting stimuli from the secondary task during driving.

Paw Preference Correlates to Task Performance in Dogs

NARCIS (Netherlands)

Alphen, A. van; Bosse, T.; Frank, I.; Jonker, C.M.; Koeman, F.; Bara, B.G.; Barsalou, L.; Bucciarelli, M.

2005-01-01

A study involving 36 domestic dogs (Canis familiaris) in a simple search task provides evidence of a correlation between paw use and performance. The study was carried out to determine whether or not paw use is related to task performance. Different aspects of task performance were taken into

Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in COAL IGCC Powerplants

Energy Technology Data Exchange (ETDEWEB)

Kenneth A. Yackly

2004-09-30

The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, has been re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for Coal IGCC powerplants. The new program has been re-titled as ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants'' to better match the new scope. This technical progress report summarizes the work accomplished in the reporting period April 1, 2004 to August 31, 2004 on the revised Re-Directed and De-Scoped program activity. The program Tasks are: Task 1--IGCC Environmental Impact on high Temperature Materials: This first materials task has been refocused to address Coal IGCC environmental impacts on high temperature materials use in gas turbines and remains in the program. This task will screen material performance and quantify the effects of high temperature erosion and corrosion of hot gas path materials in Coal IGCC applications. The materials of interest will include those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: This second task develops and demonstrates new sensor technologies to determine the in-service health of advanced technology Coal IGCC powerplants, and remains in the program with a reduced scope. Its focus is now on only two critical sensor need areas for advanced Coal IGCC gas turbines: (1) Fuel Quality Sensor for detection of fuel impurities that could lead to rapid component degradation, and a Fuel Heating Value Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware.

The effects of experimental pain and induced optimism on working memory task performance.

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Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

2016-07-01

Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found

Preferential processing of task-irrelevant beloved-related information and task performance: Two event-related potential studies.

Science.gov (United States)

Langeslag, Sandra J E; van Strien, Jan W

2017-09-18

People who are in love have better attention for beloved-related information, but report having trouble focusing on other tasks, such as (home)work. So, romantic love can both improve and hurt cognition. Emotional information is preferentially processed, which improves task performance when the information is task-relevant, but hurts task performance when it is task-irrelevant. Because beloved-related information is highly emotional, the effects of romantic love on cognition may resemble these effects of emotion on cognition. We examined whether beloved-related information is preferentially processed even when it is task-irrelevant and whether this hurts task performance. In two event-related potential studies, participants who had recently fallen in love performed a visuospatial short-term memory task. Task-irrelevant beloved, friend, and stranger faces were presented during maintenance (Study 1), or encoding (Study 2). The Early Posterior Negativity (EPN) reflecting early automatic attentional capturing and the Late Positive Potential (LPP) reflecting sustained motivated attention were largest for beloved pictures. Thus, beloved pictures are preferentially processed even when they are task-irrelevant. Task performance and reaction times did not differ between beloved, friend, and stranger conditions. Nevertheless, self-reported obsessive thinking about the beloved tended to correlate negatively with task performance, and positively with reaction times, across conditions. So, although task-irrelevant beloved-related information does not impact task performance, more obsessive thinking about the beloved might relate to poorer and slower overall task performance. More research is needed to clarify why people experience trouble focusing on beloved-unrelated tasks and how this negative effect of love on cognition could be reduced. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigating Perfect Timesharing: The Relationship between IM-Compatible Tasks and Dual-Task Performance

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Halvorson, Kimberly M.; Ebner, Herschel; Hazeltine, Eliot

2013-01-01

Why are dual-task costs reduced with ideomotor (IM) compatible tasks (Greenwald & Shulman, 1973; Lien, Proctor & Allen, 2002)? In the present experiments, we first examine three different measures of single-task performance (pure single-task blocks, mixed blocks, and long stimulus onset asynchrony [SOA] trials in dual-task blocks) and two…

Linear models to perform treaty verification tasks for enhanced information security

International Nuclear Information System (INIS)

MacGahan, Christopher J.; Kupinski, Matthew A.; Brubaker, Erik M.; Hilton, Nathan R.; Marleau, Peter A.

2017-01-01

Linear mathematical models were applied to binary-discrimination tasks relevant to arms control verification measurements in which a host party wishes to convince a monitoring party that an item is or is not treaty accountable. These models process data in list-mode format and can compensate for the presence of variability in the source, such as uncertain object orientation and location. The Hotelling observer applies an optimal set of weights to binned detector data, yielding a test statistic that is thresholded to make a decision. The channelized Hotelling observer applies a channelizing matrix to the vectorized data, resulting in a lower dimensional vector available to the monitor to make decisions. We demonstrate how incorporating additional terms in this channelizing-matrix optimization offers benefits for treaty verification. We present two methods to increase shared information and trust between the host and monitor. The first method penalizes individual channel performance in order to maximize the information available to the monitor while maintaining optimal performance. Second, we present a method that penalizes predefined sensitive information while maintaining the capability to discriminate between binary choices. Data used in this study was generated using Monte Carlo simulations for fission neutrons, accomplished with the GEANT4 toolkit. Custom models for plutonium inspection objects were measured in simulation by a radiation imaging system. Model performance was evaluated and presented using the area under the receiver operating characteristic curve.

Linear models to perform treaty verification tasks for enhanced information security

Energy Technology Data Exchange (ETDEWEB)

MacGahan, Christopher J., E-mail: cmacgahan@optics.arizona.edu [College of Optical Sciences, The University of Arizona, 1630 E. University Blvd, Tucson, AZ 85721 (United States); Sandia National Laboratories, Livermore, CA 94551 (United States); Kupinski, Matthew A. [College of Optical Sciences, The University of Arizona, 1630 E. University Blvd, Tucson, AZ 85721 (United States); Brubaker, Erik M.; Hilton, Nathan R.; Marleau, Peter A. [Sandia National Laboratories, Livermore, CA 94551 (United States)

2017-02-01

Linear mathematical models were applied to binary-discrimination tasks relevant to arms control verification measurements in which a host party wishes to convince a monitoring party that an item is or is not treaty accountable. These models process data in list-mode format and can compensate for the presence of variability in the source, such as uncertain object orientation and location. The Hotelling observer applies an optimal set of weights to binned detector data, yielding a test statistic that is thresholded to make a decision. The channelized Hotelling observer applies a channelizing matrix to the vectorized data, resulting in a lower dimensional vector available to the monitor to make decisions. We demonstrate how incorporating additional terms in this channelizing-matrix optimization offers benefits for treaty verification. We present two methods to increase shared information and trust between the host and monitor. The first method penalizes individual channel performance in order to maximize the information available to the monitor while maintaining optimal performance. Second, we present a method that penalizes predefined sensitive information while maintaining the capability to discriminate between binary choices. Data used in this study was generated using Monte Carlo simulations for fission neutrons, accomplished with the GEANT4 toolkit. Custom models for plutonium inspection objects were measured in simulation by a radiation imaging system. Model performance was evaluated and presented using the area under the receiver operating characteristic curve.

Task-relevant cognitive and motor functions are prioritized during prolonged speed-accuracy motor task performance.

Science.gov (United States)

Solianik, Rima; Satas, Andrius; Mickeviciene, Dalia; Cekanauskaite, Agne; Valanciene, Dovile; Majauskiene, Daiva; Skurvydas, Albertas

2018-06-01

This study aimed to explore the effect of prolonged speed-accuracy motor task on the indicators of psychological, cognitive, psychomotor and motor function. Ten young men aged 21.1 ± 1.0 years performed a fast- and accurate-reaching movement task and a control task. Both tasks were performed for 2 h. Despite decreased motivation, and increased perception of effort as well as subjective feeling of fatigue, speed-accuracy motor task performance improved during the whole period of task execution. After the motor task, the increased working memory function and prefrontal cortex oxygenation at rest and during conflict detection, and the decreased efficiency of incorrect response inhibition and visuomotor tracking were observed. The speed-accuracy motor task increased the amplitude of motor-evoked potentials, while grip strength was not affected. These findings demonstrate that to sustain the performance of 2-h speed-accuracy task under conditions of self-reported fatigue, task-relevant functions are maintained or even improved, whereas less critical functions are impaired.

Trait Mindfulness and Cognitive Task Performance

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Emalee J. W. Quickel

2014-11-01

Full Text Available Mindfulness meditation (MM training has been shown to have positive effects on working memory and focused attention tasks. Clarifying the construct of mindfulness is important so that mindfulness can be studied effectively in individual differences and cognition research. The current study tested whether trait mindfulness alone explains any of the variability on task performance. Five commonly used mindfulness scales, as well as six standardized and experimental attention and working memory tasks were administered to 164 participants with no meditation experience. Confirmatory factor analysis found that the common variance denoted by measures of trait mindfulness is unrelated to the common variance among tasks requiring focused attention. These results indicate that mindfulness scales may not be capturing the attentional aspects of mindfulness. Individuals who score high on mindfulness scales do not perform better on focused attention tasks than those who score lower on mindfulness scales. These results have implications for defining and operationalizing mindfulness.

The Role of Task Complexity, Modality, and Aptitude in Narrative Task Performance

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Kormos, Judit; Trebits, Anna

2012-01-01

The study reported in this paper investigated the relationship between components of aptitude and the fluency, lexical variety, syntactic complexity, and accuracy of performance in two types of written and spoken narrative tasks. We also addressed the question of how narrative performance varies in tasks of different cognitive complexity in the…

Uncertainty analysis in the task of individual monitoring data

International Nuclear Information System (INIS)

Molokanov, A.; Badjin, V.; Gasteva, G.; Antipin, E.

2003-01-01

Assessment of internal doses is an essential component of individual monitoring programmes for workers and consists of two stages: individual monitoring measurements and interpretation of the monitoring data in terms of annual intake and/or annual internal dose. The overall uncertainty in assessed dose is a combination of the uncertainties in these stages. An algorithm and a computer code were developed for estimating the uncertainties in these stages. An algorithm and a computer code were developed for estimating the uncertainty in the assessment of internal dose in the task of individual monitoring data interpretation. Two main influencing factors are analysed in this paper: the unknown time of the exposure and variability of bioassay measurements. The aim of this analysis is to show that the algorithm is applicable in designing an individual monitoring programme for workers so as to guarantee that the individual dose calculated from individual monitoring measurements does not exceed a required limit with a certain confidence probability. (author)

Implicit and Explicit Knowledge Both Improve Dual Task Performance in a Continuous Pursuit Tracking Task.

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Ewolds, Harald E; Bröker, Laura; de Oliveira, Rita F; Raab, Markus; Künzell, Stefan

2017-01-01

The goal of this study was to investigate the effect of predictability on dual-task performance in a continuous tracking task. Participants practiced either informed (explicit group) or uninformed (implicit group) about a repeated segment in the curves they had to track. In Experiment 1 participants practices the tracking task only, dual-task performance was assessed after by combining the tracking task with an auditory reaction time task. Results showed both groups learned equally well and tracking performance on a predictable segment in the dual-task condition was better than on random segments. However, reaction times did not benefit from a predictable tracking segment. To investigate the effect of learning under dual-task situation participants in Experiment 2 practiced the tracking task while simultaneously performing the auditory reaction time task. No learning of the repeated segment could be demonstrated for either group during the training blocks, in contrast to the test-block and retention test, where participants performed better on the repeated segment in both dual-task and single-task conditions. Only the explicit group improved from test-block to retention test. As in Experiment 1, reaction times while tracking a predictable segment were no better than reaction times while tracking a random segment. We concluded that predictability has a positive effect only on the predictable task itself possibly because of a task-shielding mechanism. For dual-task training there seems to be an initial negative effect of explicit instructions, possibly because of fatigue, but the advantage of explicit instructions was demonstrated in a retention test. This might be due to the explicit memory system informing or aiding the implicit memory system.

The effect of metacognitive monitoring feedback on performance in a computer-based training simulation.

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Kim, Jung Hyup

2018-02-01

This laboratory experiment was designed to study the effect of metacognitive monitoring feedback on performance in a computer-based training simulation. According to prior research on metacognition, the accurate checking of learning is a critical part of improving the quality of human performance. However, only rarely have researchers studied the learning effects of the accurate checking of retrospective confidence judgments (RCJs) during a computer-based military training simulation. In this study, we provided participants feedback screens after they had completed a warning task and identification task in a radar monitoring simulation. There were two groups in this experiment. One group (group A) viewed the feedback screens with the flight path of all target aircraft and the triangular graphs of both RCJ scores and human performance together. The other group (group B) only watched the feedback screens with the flight path of all target aircraft. There was no significant difference in performance improvement between groups A and B for the warning task (Day 1: group A - 0.347, group B - 0.305; Day 2: group A - 0.488, group B - 0.413). However, the identification task yielded a significant difference in performance improvement between these groups (Day 1: group A - 0.174, group B - 0.1555; Day 2: group A - 0.324, group B - 0.199). The results show that debiasing self-judgment of the identification task produces a positive training effect on learners. The findings of this study will be beneficial for designing an advanced instructional strategy in a simulation-based training environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Appraisal, Coping, Task Performance, and Cardiovascular Responses during the Evaluated Speaking Task.

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Baggett, H. Lane; And Others

1996-01-01

Appraisal, coping, task performance, and cardiovascular responses were examined among men high and low in speech anxiety who prepared and performed a speech under evaluative conditions. Speech-anxious men saw the task as more threatening. They were more stressed, anxious, distracted, and aware of their emotions, focused on the passage of time, and…

Increasing On-Task Behavior in the Classroom: Extension of Self-Monitoring Strategies

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Amato-Zech, Natalie A.; Hoff, Kathryn E.; Doepke, Karla J.

2006-01-01

We examined the effectiveness of a tactile self-monitoring prompt to increase on-task behaviors among 3 elementary-aged students in a special education classroom. Students were taught to self-monitor their attention by using the MotivAider (MotivAider, 2000), an electronic beeper that vibrates to provide a tactile cue to self-monitor. An ABAB…

Alignment performance monitoring for ASML systems

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Chung, Woong-Jae; Temchenko, Vlad; Hauck, Tarja; Schmidt, Sebastian

2006-03-01

In today's semiconductor industry downscaling of the IC design puts a stringent requirement on pattern overlay control. Tighter overlay requirements lead to exceedingly higher rework rates, meaning additional costs to manufacturing. Better alignment control became a target of engineering efforts to decrease rework rate for high-end technologies. Overlay performance is influenced by known parameters such as "Shift, Scaling, Rotation, etc", and unknown parameters defined as "Process Induced Variation", which are difficult to control by means of a process automation system. In reality, this process-induced variation leads to a strong wafer to wafer, or lot to lot variation, which are not easy to detect in the mass-production environment which uses sampling overlay measurements for only several wafers in a lot. An engineering task of finding and correcting a root cause for Process Induced Variations of overlay performance will be greatly simplified if the unknown parameters could be tracked for each wafer. This paper introduces an alignment performance monitoring method based on analysis of automatically generated "AWE" files for ASML scanner systems. Because "AWE" files include alignment results for each aligned wafer, it is possible to use them for monitoring, controlling and correcting the causes of "process induced" overlay performance without requiring extra measurement time. Since "AWE" files include alignment information for different alignment marks, it is also possible to select and optimize the best alignment recipe for each alignment strategy. Several case studies provided in our paper will demonstrate how AWE file analysis can be used to assist engineer in interpreting pattern alignment data. Since implementing our alignment data monitoring method, we were able to achieve significant improvement of alignment and overlay performance without additional overlay measurement time. We also noticed that the rework rate coming from alignment went down and

On the importance of Task 1 and error performance measures in PRP dual-task studies

Science.gov (United States)

Strobach, Tilo; Schütz, Anja; Schubert, Torsten

2015-01-01

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects. PMID:25904890

On the importance of Task 1 and error performance measures in PRP dual-task studies.

Science.gov (United States)

Strobach, Tilo; Schütz, Anja; Schubert, Torsten

2015-01-01

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

Comparing Young and Elderly Serial Reaction Time Task Performance on Repeated and Random Conditions

Directory of Open Access Journals (Sweden)

Fatemeh Ehsani

2012-07-01

Full Text Available Objectives: Acquisition motor skill training in elderly is at great importance. The main purpose of this study was to compare young and elderly performance in serial reaction time task on different repeated and random conditions. Methods & Materials: A serial reaction time task by using software was applied for studying motor learning in 30 young and 30 elderly. Each group divided randomly implicitly and explicitly into subgroups. A task 4 squares with different colors appeared on the monitor and subjects were asked to press its defined key immediately after observing it. Subjects practiced 8 motor blocks (4 repeated blocks, then 2 random blocks and 2 repeated blocks. Block time that was dependent variable measured and Independent-samples t- test with repeated ANOVA measures were used in this test. Results: young groups performed both repeated and random sequences significantly faster than elderly (P0.05. Explicit older subgroup performed 7,8 blocks slower than 6 block with a significant difference (P<0.05. Conclusion: Young adults discriminate high level performance than elderly in both repeated and random practice. Elderly performed random practice better than repeated practice.

A Comparison of Self-Monitoring with and without Reinforcement to Improve On-Task Classroom Behavior

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Davis, Tonya N.; Dacus, Sharon; Bankhead, Jenna; Haupert, Megan; Fuentes, Lisa; Zoch, Tamara; Kang, Soyeon; Attai, Shanna; Lang, Russell

2014-01-01

In this study we analyzed the effects of a self-monitoring and self-monitoring plus reinforcement intervention on classroom behavior. A typically-developing high school student demonstrating difficulty staying on-task during classroom instruction was observed in three classroom settings associated with high levels of off-task behavior. During…

On the importance of Task 1 and error performance measures in PRP dual-task studies

Directory of Open Access Journals (Sweden)

Tilo eStrobach

2015-04-01

Full Text Available The Psychological Refractory Period (PRP paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and 2 are presented with variable stimulus onset asynchronies (SOAs and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e. decreasing SOAs do not increase RTs and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/ or error rates in Task 1. This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

The monitoring and control of task sequences in human and non-human primates

Directory of Open Access Journals (Sweden)

Theresa M Desrochers

2016-01-01

Full Text Available Our ability to plan and execute a series of tasks leading to a desired goal requires remarkable coordination between sensory, motor, and decision-related systems. Prefrontal cortex is thought to play a central role in this coordination, especially when actions must be assembled extemporaneously and cannot be programmed as a rote series of movements. A central component of this flexible behavior is the moment-by-moment allocation of working memory and attention. The ubiquity of sequence planning in our everyday lives belies the neural complexity that supports this capacity, and little is known about how frontal cortical regions orchestrate the monitoring and control of sequential behaviors. For example, it remains unclear if and how sensory cortical areas, which provide essential driving inputs for behavior, are modulated by the frontal cortex during these tasks. Here we review what is known about moment-to-moment monitoring as it relates to visually guided, rule-driven behaviors that change over time. We highlight recent human work that shows how the rostrolateral prefrontal cortex (RLPFC participates in monitoring during task sequences. Neurophysiological data from monkeys suggests that monitoring may be accomplished by neurons that respond to items within the sequence and may in turn influence the tuning properties of neurons in posterior sensory areas. Understanding the interplay between proceduralized or habitual acts and supervised control of sequences is key to our understanding of sequential task execution. A crucial bridge will be the use of experimental protocols that allow for the examination of the functional homology between monkeys and humans. We illustrate how task sequences may be parceled into components and examined experimentally, thereby opening future avenues of investigation into the neural basis of sequential monitoring and control.

Impact of task design on task performance and injury risk: case study of a simulated drilling task.

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Alabdulkarim, Saad; Nussbaum, Maury A; Rashedi, Ehsan; Kim, Sunwook; Agnew, Michael; Gardner, Richard

2017-06-01

Existing evidence is limited regarding the influence of task design on performance and ergonomic risk, or the association between these two outcomes. In a controlled experiment, we constructed a mock fuselage to simulate a drilling task common in aircraft manufacturing, and examined the effect of three levels of workstation adjustability on performance as measured by productivity (e.g. fuselage completion time) and quality (e.g. fuselage defective holes), and ergonomic risk as quantified using two common methods (rapid upper limb assessment and the strain index). The primary finding was that both productivity and quality significantly improved with increased adjustability, yet this occurred only when that adjustability succeeded in reducing ergonomic risk. Supporting the inverse association between ergonomic risk and performance, the condition with highest adjustability created the lowest ergonomic risk and the best performance while there was not a substantial difference in ergonomic risk between the other two conditions, in which performance was also comparable. Practitioner Summary: Findings of this study supported a causal relationship between task design and both ergonomic risk and performance, and that ergonomic risk and performance are inversely associated. While future work is needed under more realistic conditions and a broader population, these results may be useful for task (re)design and to help cost-justify some ergonomic interventions.

Workplace for analysis of task performance

NARCIS (Netherlands)

Bos, J; Mulder, LJM; van Ouwerkerk, RJ; Maarse, FJ; Akkerman, AE; Brand, AN; Mulder, LJM

2003-01-01

In current research on mental workload and task performance a large gap exists between laboratory based studies and research projects in real life working practice. Tasks conducted within a laboratory environment often lack a strong resemblance with real life working situations. This paper presents

Pleasantness of Creative Tasks and Creative Performance

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Zenasni, Franck; Lubart, Todd

2011-01-01

To examine the impact of emotion on creative potential, experimental studies have typically focused on the impact of induced or spontaneous mood states on creative performance. In this report the relationship between the perceived pleasantness of tasks (using divergent thinking and story writing tasks) and creative performance was examined.…

No Evidence That Gratitude Enhances Neural Performance Monitoring or Conflict-Driven Control.

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Saunders, Blair; He, Frank F H; Inzlicht, Michael

2015-01-01

It has recently been suggested that gratitude can benefit self-regulation by reducing impulsivity during economic decision making. We tested if comparable benefits of gratitude are observed for neural performance monitoring and conflict-driven self-control. In a pre-post design, 61 participants were randomly assigned to either a gratitude or happiness condition, and then performed a pre-induction flanker task. Subsequently, participants recalled an autobiographical event where they had felt grateful or happy, followed by a post-induction flanker task. Despite closely following existing protocols, participants in the gratitude condition did not report elevated gratefulness compared to the happy group. In regard to self-control, we found no association between gratitude--operationalized by experimental condition or as a continuous predictor--and any control metric, including flanker interference, post-error adjustments, or neural monitoring (the error-related negativity, ERN). Thus, while gratitude might increase economic patience, such benefits may not generalize to conflict-driven control processes.

When predictions take control: The effect of task predictions on task switching performance

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Wout eDuthoo

2012-08-01

Full Text Available In this paper, we aimed to investigate the role of self-generated predictions in the flexible control of behaviour. Therefore, we ran a task switching experiment in which participants were asked to try to predict the upcoming task in three conditions varying in switch rate (30%, 50% and 70%. Irrespective of their predictions, the colour of the target indicated which task participants had to perform. In line with previous studies (Mayr, 2006; Monsell & Mizon, 2006, the switch cost was attenuated as the switch rate increased. Importantly, a clear task repetition bias was found in all conditions, yet the task repetition prediction rate dropped from 78% over 66% to 49% with increasing switch probability in the three conditions. Irrespective of condition, the switch cost was strongly reduced in expectation of a task alternation compared to the cost of an unexpected task alternation following repetition predictions. Hence, our data suggest that the reduction in the switch cost with increasing switch probability is caused by a diminished expectancy for the task to repeat. Taken together, this paper highlights the importance of predictions in the flexible control of behaviour, and suggests a crucial role for task repetition expectancy in the context-sensitive adjusting of task switching performance.

Sleep deprivation and time-on-task performance decrement in the rat psychomotor vigilance task.

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Oonk, Marcella; Davis, Christopher J; Krueger, James M; Wisor, Jonathan P; Van Dongen, Hans P A

2015-03-01

The rat psychomotor vigilance task (rPVT) was developed as a rodent analog of the human psychomotor vigilance task (hPVT). We examined whether rPVT performance displays time-on-task effects similar to those observed on the hPVT. The rPVT requires rats to respond to a randomly presented light stimulus to obtain a water reward. Rats were water deprived for 22 h prior to each 30-min rPVT session to motivate performance. We analyzed rPVT performance over time on task and as a function of the response-stimulus interval, at baseline and after sleep deprivation. The study was conducted in an academic research vivarium. Male Long-Evans rats were trained to respond to a 0.5 sec stimulus light within 3 sec of stimulus onset. Complete data were available for n = 20 rats. Rats performed the rPVT for 30 min at baseline and after 24 h total sleep deprivation by gentle handling. Compared to baseline, sleep deprived rats displayed increased performance lapses and premature responses, similar to hPVT lapses of attention and false starts. However, in contrast to hPVT performance, the time-on-task performance decrement was not significantly enhanced by sleep deprivation. Moreover, following sleep deprivation, rPVT response times were not consistently increased after short response-stimulus intervals. The rPVT manifests similarities to the hPVT in global performance outcomes, but not in post-sleep deprivation effects of time on task and response-stimulus interval. © 2015 Associated Professional Sleep Societies, LLC.

Differential Effects of Reinforcement on the Self-Monitoring of On-Task Behavior

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Otero, Tiffany L.; Haut, Jillian M.

2016-01-01

In the current study, the differential effects of reinforcement on a self-monitoring intervention were evaluated. Three students nominated by their teachers for having a marked difficultly maintaining on-task behaviors participated in the study. Using an alternating treatments single-case design to assess self-monitoring with and without…

Exploring the role of task performance and learning style on prefrontal hemodynamics during a working memory task.

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Anderson, Afrouz A; Parsa, Kian; Geiger, Sydney; Zaragoza, Rachel; Kermanian, Riley; Miguel, Helga; Dashtestani, Hadis; Chowdhry, Fatima A; Smith, Elizabeth; Aram, Siamak; Gandjbakhche, Amir H

2018-01-01

Existing literature outlines the quality and location of activation in the prefrontal cortex (PFC) during working memory (WM) tasks. However, the effects of individual differences on the underlying neural process of WM tasks are still unclear. In this functional near infrared spectroscopy study, we administered a visual and auditory n-back task to examine activation in the PFC while considering the influences of task performance, and preferred learning strategy (VARK score). While controlling for age, results indicated that high performance (HP) subjects (accuracy > 90%) showed task dependent lower activation compared to normal performance subjects in PFC region Specifically HP groups showed lower activation in left dorsolateral PFC (DLPFC) region during performance of auditory task whereas during visual task they showed lower activation in the right DLPFC. After accounting for learning style, we found a correlation between visual and aural VARK score and level of activation in the PFC. Subjects with higher visual VARK scores displayed lower activation during auditory task in left DLPFC, while those with higher visual scores exhibited higher activation during visual task in bilateral DLPFC. During performance of auditory task, HP subjects had higher visual VARK scores compared to NP subjects indicating an effect of learning style on the task performance and activation. The results of this study show that learning style and task performance can influence PFC activation, with applications toward neurological implications of learning style and populations with deficits in auditory or visual processing.

Performance monitoring and error significance in patients with obsessive-compulsive disorder.

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Endrass, Tanja; Schuermann, Beate; Kaufmann, Christan; Spielberg, Rüdiger; Kniesche, Rainer; Kathmann, Norbert

2010-05-01

Performance monitoring has been consistently found to be overactive in obsessive-compulsive disorder (OCD). The present study examines whether performance monitoring in OCD is adjusted with error significance. Therefore, errors in a flanker task were followed by neutral (standard condition) or punishment feedbacks (punishment condition). In the standard condition patients had significantly larger error-related negativity (ERN) and correct-related negativity (CRN) ampliudes than controls. But, in the punishment condition groups did not differ in ERN and CRN amplitudes. While healthy controls showed an amplitude enhancement between standard and punishment condition, OCD patients showed no variation. In contrast, group differences were not found for the error positivity (Pe): both groups had larger Pe amplitudes in the punishment condition. Results confirm earlier findings of overactive error monitoring in OCD. The absence of a variation with error significance might indicate that OCD patients are unable to down-regulate their monitoring activity according to external requirements. Copyright 2010 Elsevier B.V. All rights reserved.

Computer task performance by subjects with Duchenne muscular dystrophy.

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Malheiros, Silvia Regina Pinheiro; da Silva, Talita Dias; Favero, Francis Meire; de Abreu, Luiz Carlos; Fregni, Felipe; Ribeiro, Denise Cardoso; de Mello Monteiro, Carlos Bandeira

2016-01-01

Two specific objectives were established to quantify computer task performance among people with Duchenne muscular dystrophy (DMD). First, we compared simple computational task performance between subjects with DMD and age-matched typically developing (TD) subjects. Second, we examined correlations between the ability of subjects with DMD to learn the computational task and their motor functionality, age, and initial task performance. The study included 84 individuals (42 with DMD, mean age of 18±5.5 years, and 42 age-matched controls). They executed a computer maze task; all participants performed the acquisition (20 attempts) and retention (five attempts) phases, repeating the same maze. A different maze was used to verify transfer performance (five attempts). The Motor Function Measure Scale was applied, and the results were compared with maze task performance. In the acquisition phase, a significant decrease was found in movement time (MT) between the first and last acquisition block, but only for the DMD group. For the DMD group, MT during transfer was shorter than during the first acquisition block, indicating improvement from the first acquisition block to transfer. In addition, the TD group showed shorter MT than the DMD group across the study. DMD participants improved their performance after practicing a computational task; however, the difference in MT was present in all attempts among DMD and control subjects. Computational task improvement was positively influenced by the initial performance of individuals with DMD. In turn, the initial performance was influenced by their distal functionality but not their age or overall functionality.

Continuous Performance Tasks: Not Just about Sustaining Attention

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Roebuck, Hettie; Freigang, Claudia; Barry, Johanna G.

2016-01-01

Purpose: Continuous performance tasks (CPTs) are used to measure individual differences in sustained attention. Many different stimuli have been used as response targets without consideration of their impact on task performance. Here, we compared CPT performance in typically developing adults and children to assess the role of stimulus processing…

A continuous time-resolved measure decoded from EEG oscillatory activity predicts working memory task performance.

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Astrand, Elaine

2018-06-01

Working memory (WM), crucial for successful behavioral performance in most of our everyday activities, holds a central role in goal-directed behavior. As task demands increase, inducing higher WM load, maintaining successful behavioral performance requires the brain to work at the higher end of its capacity. Because it is depending on both external and internal factors, individual WM load likely varies in a continuous fashion. The feasibility to extract such a continuous measure in time that correlates to behavioral performance during a working memory task remains unsolved. Multivariate pattern decoding was used to test whether a decoder constructed from two discrete levels of WM load can generalize to produce a continuous measure that predicts task performance. Specifically, a linear regression with L2-regularization was chosen with input features from EEG oscillatory activity recorded from healthy participants while performing the n-back task, [Formula: see text]. The feasibility to extract a continuous time-resolved measure that correlates positively to trial-by-trial working memory task performance is demonstrated (r  =  0.47, p  performance before action (r  =  0.49, p  <  0.05). We show that the extracted continuous measure enables to study the temporal dynamics of the complex activation pattern of WM encoding during the n-back task. Specifically, temporally precise contributions of different spectral features are observed which extends previous findings of traditional univariate approaches. These results constitute an important contribution towards a wide range of applications in the field of cognitive brain-machine interfaces. Monitoring mental processes related to attention and WM load to reduce the risk of committing errors in high-risk environments could potentially prevent many devastating consequences or using the continuous measure as neurofeedback opens up new possibilities to develop novel rehabilitation techniques for

Analysis of Skeletal Muscle Metrics as Predictors of Functional Task Performance

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Ryder, Jeffrey W.; Buxton, Roxanne E.; Redd, Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle J.; Fiedler, James; Ploutz-Snyder, Robert J.; Bloomberg, Jacob J.; Ploutz-Snyder, Lori L.

2010-01-01

PURPOSE: The ability to predict task performance using physiological performance metrics is vital to ensure that astronauts can execute their jobs safely and effectively. This investigation used a weighted suit to evaluate task performance at various ratios of strength, power, and endurance to body weight. METHODS: Twenty subjects completed muscle performance tests and functional tasks representative of those that would be required of astronauts during planetary exploration (see table for specific tests/tasks). Subjects performed functional tasks while wearing a weighted suit with additional loads ranging from 0-120% of initial body weight. Performance metrics were time to completion for all tasks except hatch opening, which consisted of total work. Task performance metrics were plotted against muscle metrics normalized to "body weight" (subject weight + external load; BW) for each trial. Fractional polynomial regression was used to model the relationship between muscle and task performance. CONCLUSION: LPMIF/BW is the best predictor of performance for predominantly lower-body tasks that are ambulatory and of short duration. LPMIF/BW is a very practical predictor of occupational task performance as it is quick and relatively safe to perform. Accordingly, bench press work best predicts hatch-opening work performance.

Masticatory muscle activity during deliberately performed oral tasks

International Nuclear Information System (INIS)

Farella, M; Palla, S; Erni, S; Gallo, L M; Michelotti, A

2008-01-01

The aim of this study was to investigate masticatory muscle activity during deliberately performed functional and non-functional oral tasks. Electromyographic (EMG) surface activity was recorded unilaterally from the masseter, anterior temporalis and suprahyoid muscles in 11 subjects (5 men, 6 women; age = 34.6 ± 10.8 years), who were accurately instructed to perform 30 different oral tasks under computer guidance using task markers. Data were analyzed by descriptive statistics, repeated measurements analysis of variance (ANOVA) and hierarchical cluster analysis. The maximum EMG amplitude of the masseter and anterior temporalis muscles was more often found during hard chewing tasks than during maximum clenching tasks. The relative contribution of masseter and anterior temporalis changed across the tasks examined (F ≥ 5.2; p ≤ 0.001). The masseter muscle was significantly (p ≤ 0.05) more active than the anterior temporalis muscle during tasks involving incisal biting, jaw protrusion, laterotrusion and jaw cupping, the difference being statistically significant (p ≤ 0.05). The anterior temporalis muscle was significantly (p ≤ 0.01) more active than the masseter muscle during tasks performed in intercuspal position, during tooth grinding, and during hard chewing on the working side. Based upon the relative contribution of the masseter, anterior temporalis, and suprahyoid muscles, the investigated oral tasks could be grouped into six separate clusters. The findings provided further insight into muscle- and task-specific EMG patterns during functional and non-functional oral behaviors

Uncertainty Monitoring by Young Children in a Computerized Task

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Michael J. Beran

2012-01-01

Full Text Available Adult humans show sophisticated metacognitive abilities, including the ability to monitor uncertainty. Unfortunately, most measures of uncertainty monitoring are limited to use with adults due to their general complexity and dependence on explicit verbalization. However, recent research with nonhuman animals has successfully developed measures of uncertainty monitoring that are simple and do not require explicit verbalization. The purpose of this study was to investigate metacognition in young children using uncertainty monitoring tests developed for nonhumans. Children judged whether stimuli were more pink or blue—stimuli nearest the pink-blue midpoint were the most uncertain and the most difficult to classify. Children also had an option to acknowledge difficulty and gain the necessary information for correct classification. As predicted, children most often asked for help on the most difficult stimuli. This result confirms that some metacognitive abilities appear early in cognitive development. The tasks of animal metacognition research clearly have substantial utility for exploring the early developmental roots of human metacognition.

Priming performance-related concerns induces task-related mind-wandering.

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Jordano, Megan L; Touron, Dayna R

2017-10-01

Two experiments tested the hypothesis that priming of performance-related concerns would (1) increase the frequency of task-related mind-wandering (i.e., task-related interference; TRI) and (2) decrease task performance. In each experiment, sixty female participants completed an operation span task (OSPAN) containing thought content probes. The task was framed as a math task for those in a condition primed for math-related stereotype threat and as a memory task for those in a control condition. In both studies, women whose performance-related concerns were primed via stereotype threat reported more TRI than women in the control. The second experiment used a more challenging OSPAN task and stereotype primed women also had lower math accuracy than controls. These results support the "control failures×current concerns" framework of mind-wandering, which posits that the degree to which the environmental context triggers personal concerns influences both mind-wandering frequency and content. Copyright © 2017 Elsevier Inc. All rights reserved.

Within-person relationship between self-efficacy and performance across trials. Effect of task objective and task type.

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Hepler, Teri J; Ritchie, Jason; Hill, Christopher R

2017-07-05

Self-efficacy has been shown to be a consistent, positive predictor of between-persons performance in sport. However, there have been equivocal results regarding the influence of self-efficacy on a person's performance over time. This study investigated the influence of self-efficacy on motor skill performance across trials with respect to two different task objectives and task types. Participants (N=84) performed 4 blocks of 10 trials of a dart throwing (closed skill) and a hitting (open skill) task under 2 different task objectives: competitive and goal-striving. For the goal-striving condition, success was defined as reaching a pre-determined performance level. The competitive condition involved competing against an opponent. Hierarchical linear modeling was used to examine the influence of past performance and self-efficacy on the within-person performance across multiple trials. Previous performance was negatively related with subsequent performance on all conditions. Self-efficacy was not a significant predictor of performance on any of the conditions. While task objective and task type did not moderate the efficacy-performance relationship in the current study, it is important to consider the role of other moderators in future research.

A continuous time-resolved measure decoded from EEG oscillatory activity predicts working memory task performance

Science.gov (United States)

Astrand, Elaine

2018-06-01

Objective. Working memory (WM), crucial for successful behavioral performance in most of our everyday activities, holds a central role in goal-directed behavior. As task demands increase, inducing higher WM load, maintaining successful behavioral performance requires the brain to work at the higher end of its capacity. Because it is depending on both external and internal factors, individual WM load likely varies in a continuous fashion. The feasibility to extract such a continuous measure in time that correlates to behavioral performance during a working memory task remains unsolved. Approach. Multivariate pattern decoding was used to test whether a decoder constructed from two discrete levels of WM load can generalize to produce a continuous measure that predicts task performance. Specifically, a linear regression with L2-regularization was chosen with input features from EEG oscillatory activity recorded from healthy participants while performing the n-back task, n\\in [1,2] . Main results. The feasibility to extract a continuous time-resolved measure that correlates positively to trial-by-trial working memory task performance is demonstrated (r  =  0.47, p  <  0.05). It is furthermore shown that this measure allows to predict task performance before action (r  =  0.49, p  <  0.05). We show that the extracted continuous measure enables to study the temporal dynamics of the complex activation pattern of WM encoding during the n-back task. Specifically, temporally precise contributions of different spectral features are observed which extends previous findings of traditional univariate approaches. Significance. These results constitute an important contribution towards a wide range of applications in the field of cognitive brain–machine interfaces. Monitoring mental processes related to attention and WM load to reduce the risk of committing errors in high-risk environments could potentially prevent many devastating consequences or

Cognitive and motor dual task gait training improve dual task gait performance after stroke - A randomized controlled pilot trial.

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Liu, Yan-Ci; Yang, Yea-Ru; Tsai, Yun-An; Wang, Ray-Yau

2017-06-22

This study investigated effects of cognitive and motor dual task gait training on dual task gait performance in stroke. Participants (n = 28) were randomly assigned to cognitive dual task gait training (CDTT), motor dual task gait training (MDTT), or conventional physical therapy (CPT) group. Participants in CDTT or MDTT group practiced the cognitive or motor tasks respectively during walking. Participants in CPT group received strengthening, balance, and gait training. The intervention was 30 min/session, 3 sessions/week for 4 weeks. Three test conditions to evaluate the training effects were single walking, walking while performing cognitive task (serial subtraction), and walking while performing motor task (tray-carrying). Parameters included gait speed, dual task cost of gait speed (DTC-speed), cadence, stride time, and stride length. After CDTT, cognitive-motor dual task gait performance (stride length and DTC-speed) was improved (p = 0.021; p = 0.015). After MDTT, motor dual task gait performance (gait speed, stride length, and DTC-speed) was improved (p = 0.008; p = 0.008; p = 0.008 respectively). It seems that CDTT improved cognitive dual task gait performance and MDTT improved motor dual task gait performance although such improvements did not reach significant group difference. Therefore, different types of dual task gait training can be adopted to enhance different dual task gait performance in stroke.

Self-Efficacy, Task Complexity and Task Performance: Exploring Interactions in Two Versions of Vocabulary Learning Tasks

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Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2012-01-01

The present study aimed for better understanding of the interactions between task complexity and students' self-efficacy beliefs and students' use of learning strategies, and finally their interacting effects on task performance. This investigation was carried out in the context of Chinese students learning English as a foreign language in a…

Involvement of the anterior cingulate cortex in time-based prospective memory task monitoring: An EEG analysis of brain sources using Independent Component and Measure Projection Analysis.

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Gabriela Cruz

Full Text Available Time-based prospective memory (PM, remembering to do something at a particular moment in the future, is considered to depend upon self-initiated strategic monitoring, involving a retrieval mode (sustained maintenance of the intention plus target checking (intermittent time checks. The present experiment was designed to explore what brain regions and brain activity are associated with these components of strategic monitoring in time-based PM tasks.24 participants were asked to reset a clock every four minutes, while performing a foreground ongoing word categorisation task. EEG activity was recorded and data were decomposed into source-resolved activity using Independent Component Analysis. Common brain regions across participants, associated with retrieval mode and target checking, were found using Measure Projection Analysis.Participants decreased their performance on the ongoing task when concurrently performed with the time-based PM task, reflecting an active retrieval mode that relied on withdrawal of limited resources from the ongoing task. Brain activity, with its source in or near the anterior cingulate cortex (ACC, showed changes associated with an active retrieval mode including greater negative ERP deflections, decreased theta synchronization, and increased alpha suppression for events locked to the ongoing task while maintaining a time-based intention. Activity in the ACC was also associated with time-checks and found consistently across participants; however, we did not find an association with time perception processing per se.The involvement of the ACC in both aspects of time-based PM monitoring may be related to different functions that have been attributed to it: strategic control of attention during the retrieval mode (distributing attentional resources between the ongoing task and the time-based task and anticipatory/decision making processing associated with clock-checks.

The impact of task characteristics on the performance of nursing teams

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Azlyn Ahmad Zawawi, PhD

2017-07-01

Conclusions: This study demonstrated that task significance is important to predict team task performance. Task significance reflects meaningfulness and nobility of tasks, thus elevate the desire to perform better in each assigned task.

Real time kernel performance monitoring with SystemTap

CERN Multimedia

CERN. Geneva

2018-01-01

SystemTap is a dynamic method of monitoring and tracing the operation of a running Linux kernel. In this talk I will present a few practical use cases where SystemTap allowed me to turn otherwise complex userland monitoring tasks in simple kernel probes.

Musical training, bilingualism, and executive function: a closer look at task switching and dual-task performance.

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Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

2015-07-01

This study investigated whether musical training and bilingualism are associated with enhancements in specific components of executive function, namely, task switching and dual-task performance. Participants (n = 153) belonging to one of four groups (monolingual musician, bilingual musician, bilingual non-musician, or monolingual non-musician) were matched on age and socioeconomic status and administered task switching and dual-task paradigms. Results demonstrated reduced global and local switch costs in musicians compared with non-musicians, suggesting that musical training can contribute to increased efficiency in the ability to shift flexibly between mental sets. On dual-task performance, musicians also outperformed non-musicians. There was neither a cognitive advantage for bilinguals relative to monolinguals, nor an interaction between music and language to suggest additive effects of both types of experience. These findings demonstrate that long-term musical training is associated with improvements in task switching and dual-task performance. Copyright © 2014 Cognitive Science Society, Inc.

Effect of pre-task music on sports or exercise performance.

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Smirmaul, Bruno P

2017-01-01

Pre-task music is a very common strategy among sports competitors. However, as opposed to in-task music, the scientific evidence to support its ergogenic effects on either sports or exercise performance is limited. This brief review critically addresses the existing literature investigating the effects of pre-task music on sports and exercise performance, focusing on the methods and results of experimental studies, and offers basic and practical recommendations. In July 2015, a comprehensive literature search was performed in Web of Science, PubMed, and Google Scholar using the following key words in combination: "pre-task music," "pre-test music," "pre-exercise music," "exercise performance," "sports performance." The literature search was further expanded by both hand searching review articles on the topic and by searching the reference lists from the articles retrieved for any relevant references. Overall, a total of 15 studies in 14 articles were included. Pre-task music research has been unsystematic, methodologically limited and infrequent. Using this review as a starting point to overcome previous methodological limitations when designing future experiments may contribute to the development of pre-task music research, which is still in its infancy. Currently, there is no sufficient evidence to support the overall ergogenic effects of pre-task music on sports or exercise performance. Nonetheless, pre-task music has showed a likely ergogenic effect on shorter and predominantly anaerobic tasks such as grip strength, Wingate test, and short-duration sports or sports-like tasks, in contrast to longer and predominantly aerobic tasks.

Ability Beliefs, Task Value, and Performance as a Function of Race in a Dart-Throwing Task

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Gao, Zan; Kosma, Maria; Harrison, Louis, Jr.

2009-01-01

This study examines differences in self-efficacy, expectancy-related beliefs, task value, and performance in a dart-throwing task as a function of race among diverse college students using the expectancy-value model and self-efficacy theory. It also examines the predictive contributions of these beliefs on task performance within each racial…

Training improves laparoscopic tasks performance and decreases operator workload.

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Hu, Jesse S L; Lu, Jirong; Tan, Wee Boon; Lomanto, Davide

2016-05-01

It has been postulated that increased operator workload during task performance may increase fatigue and surgical errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a validated tool for self-assessment for workload. Our study aims to assess the relationship of workload and performance of novices in simulated laparoscopic tasks of different complexity levels before and after training. Forty-seven novices without prior laparoscopic experience were recruited in a trial to investigate whether training improves task performance as well as mental workload. The participants were tested on three standard tasks (ring transfer, precision cutting and intracorporeal suturing) in increasing complexity based on the Fundamentals of Laparoscopic Surgery (FLS) curriculum. Following a period of training and rest, participants were tested again. Test scores were computed from time taken and time penalties for precision errors. Test scores and NASA-TLX scores were recorded pre- and post-training and analysed using paired t tests. One-way repeated measures ANOVA was used to analyse differences in NASA-TLX scores between the three tasks. NASA-TLX score was lowest with ring transfer and highest with intracorporeal suturing. This was statistically significant in both pre-training (p NASA-TLX scores mirror the changes in test scores for the three tasks. Workload scores decreased significantly after training for all three tasks (ring transfer = 2.93, p NASA-TLX score is an accurate reflection of the complexity of simulated laparoscopic tasks in the FLS curriculum. This also correlates with the relationship of test scores between the three tasks. Simulation training improves both performance score and workload score across the tasks.

Event-Related-Potential (ERP) Correlates of Performance Monitoring in Adults With Attention-Deficit Hyperactivity Disorder (ADHD)

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Marquardt, Lynn; Eichele, Heike; Lundervold, Astri J.; Haavik, Jan; Eichele, Tom

2018-01-01

Introduction: Attention-deficit hyperactivity disorder (ADHD) is one of the most frequent neurodevelopmental disorders in children and tends to persist into adulthood. Evidence from neuropsychological, neuroimaging, and electrophysiological studies indicates that alterations of error processing are core symptoms in children and adolescents with ADHD. To test whether adults with ADHD show persisting deficits and compensatory processes, we investigated performance monitoring during stimulus-evaluation and response-selection, with a focus on errors, as well as within-group correlations with symptom scores. Methods: Fifty-five participants (27 ADHD and 28 controls) aged 19–55 years performed a modified flanker task during EEG recording with 64 electrodes, and the ADHD and control groups were compared on measures of behavioral task performance, event-related potentials of performance monitoring (N2, P3), and error processing (ERN, Pe). Adult ADHD Self-Report Scale (ASRS) was used to assess ADHD symptom load. Results: Adults with ADHD showed higher error rates in incompatible trials, and these error rates correlated positively with the ASRS scores. Also, we observed lower P3 amplitudes in incompatible trials, which were inversely correlated with symptom load in the ADHD group. Adults with ADHD also displayed reduced error-related ERN and Pe amplitudes. There were no significant differences in reaction time (RT) and RT variability between the two groups. Conclusion: Our findings show deviations of electrophysiological measures, suggesting reduced effortful engagement of attentional and error-monitoring processes in adults with ADHD. Associations between ADHD symptom scores, event-related potential amplitudes, and poorer task performance in the ADHD group further support this notion. PMID:29706908

Event-Related-Potential (ERP Correlates of Performance Monitoring in Adults With Attention-Deficit Hyperactivity Disorder (ADHD

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Lynn Marquardt

2018-04-01

Full Text Available Introduction: Attention-deficit hyperactivity disorder (ADHD is one of the most frequent neurodevelopmental disorders in children and tends to persist into adulthood. Evidence from neuropsychological, neuroimaging, and electrophysiological studies indicates that alterations of error processing are core symptoms in children and adolescents with ADHD. To test whether adults with ADHD show persisting deficits and compensatory processes, we investigated performance monitoring during stimulus-evaluation and response-selection, with a focus on errors, as well as within-group correlations with symptom scores.Methods: Fifty-five participants (27 ADHD and 28 controls aged 19–55 years performed a modified flanker task during EEG recording with 64 electrodes, and the ADHD and control groups were compared on measures of behavioral task performance, event-related potentials of performance monitoring (N2, P3, and error processing (ERN, Pe. Adult ADHD Self-Report Scale (ASRS was used to assess ADHD symptom load.Results: Adults with ADHD showed higher error rates in incompatible trials, and these error rates correlated positively with the ASRS scores. Also, we observed lower P3 amplitudes in incompatible trials, which were inversely correlated with symptom load in the ADHD group. Adults with ADHD also displayed reduced error-related ERN and Pe amplitudes. There were no significant differences in reaction time (RT and RT variability between the two groups.Conclusion: Our findings show deviations of electrophysiological measures, suggesting reduced effortful engagement of attentional and error-monitoring processes in adults with ADHD. Associations between ADHD symptom scores, event-related potential amplitudes, and poorer task performance in the ADHD group further support this notion.

Second language proficiency modulates conflict-monitoring in an oculomotor Stroop task: evidence from Hindi-English bilinguals.

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Niharika eSingh

2013-06-01

Full Text Available Many studies have confirmed the presence of a bilingual advantage which is manifested as enhanced cognitive and attention control. However, very few studies have investigated the role of second language proficiency on the modulation of conflict-monitoring in bilinguals. We investigated this by comparing high and low proficient Hindi-English bilinguals on a modified saccadic arrow Stroop task under different monitoring conditions, and tested the predictions of the bilingual executive control advantage proposal. The task of the participants was to make an eye movement towards the colour patch in the same colour as the central arrow, ignoring the patch to which the arrow was pointing. High-proficient bilinguals had overall faster saccade latency on all types of trials as compared to the low proficient bilinguals. The overall saccadic latency for high proficiency bilinguals was similarly affected by the different types of monitoring conditions, whereas conflict resolution advantage was found only for high monitoring demanding condition. The results support a conflict-monitoring account in a novel oculomotor task and also suggest that language proficiency could modulate executive control in bilinguals.

Improving Physical Task Performance with Counterfactual and Prefactual Thinking.

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Hammell, Cecilia; Chan, Amy Y C

2016-01-01

Counterfactual thinking (reflecting on "what might have been") has been shown to enhance future performance by translating information about past mistakes into plans for future action. Prefactual thinking (imagining "what might be if…") may serve a greater preparative function than counterfactual thinking as it is future-orientated and focuses on more controllable features, thus providing a practical script to prime future behaviour. However, whether or not this difference in hypothetical thought content may translate into a difference in actual task performance has been largely unexamined. In Experiment 1 (n = 42), participants performed trials of a computer-simulated physical task, in between which they engaged in either task-related hypothetical thinking (counterfactual or prefactual) or an unrelated filler task (control). As hypothesised, prefactuals contained more controllable features than counterfactuals. Moreover, participants who engaged in either form of hypothetical thinking improved significantly in task performance over trials compared to participants in the control group. The difference in thought content between counterfactuals and prefactuals, however, did not yield a significant difference in performance improvement. Experiment 2 (n = 42) replicated these findings in a dynamic balance task environment. Together, these findings provide further evidence for the preparatory function of counterfactuals, and demonstrate that prefactuals share this same functional characteristic.

Hysteresis in Mental Workload and Task Performance: The Influence of Demand Transitions and Task Prioritization.

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Jansen, Reinier J; Sawyer, Ben D; van Egmond, René; de Ridder, Huib; Hancock, Peter A

2016-12-01

We examine how transitions in task demand are manifested in mental workload and performance in a dual-task setting. Hysteresis has been defined as the ongoing influence of demand levels prior to a demand transition. Authors of previous studies predominantly examined hysteretic effects in terms of performance. However, little is known about the temporal development of hysteresis in mental workload. A simulated driving task was combined with an auditory memory task. Participants were instructed to prioritize driving or to prioritize both tasks equally. Three experimental conditions with low, high, and low task demands were constructed by manipulating the frequency of lane changing. Multiple measures of subjective mental workload were taken during experimental conditions. Contrary to our prediction, no hysteretic effects were found after the high- to low-demand transition. However, a hysteretic effect in mental workload was found within the high-demand condition, which degraded toward the end of the high condition. Priority instructions were not reflected in performance. Online assessment of both performance and mental workload demonstrates the transient nature of hysteretic effects. An explanation for the observed hysteretic effect in mental workload is offered in terms of effort regulation. An informed arrival at the scene is important in safety operations, but peaks in mental workload should be avoided to prevent buildup of fatigue. Therefore, communication technologies should incorporate the historical profile of task demand. © 2016, Human Factors and Ergonomics Society.

Training Attentional Control Improves Cognitive and Motor Task Performance.

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Ducrocq, Emmanuel; Wilson, Mark; Vine, Sam; Derakshan, Nazanin

2016-10-01

Attentional control is a necessary function for the regulation of goal-directed behavior. In three experiments we investigated whether training inhibitory control using a visual search task could improve task-specific measures of attentional control and performance. In Experiment 1 results revealed that training elicited a near-transfer effect, improving performance on a cognitive (antisaccade) task assessing inhibitory control. In Experiment 2 an initial far-transfer effect of training was observed on an index of attentional control validated for tennis. The principal aim of Experiment 3 was to expand on these findings by assessing objective gaze measures of inhibitory control during the performance of a tennis task. Training improved inhibitory control and performance when pressure was elevated, confirming the mechanisms by which cognitive anxiety impacts performance. These results suggest that attentional control training can improve inhibition and reduce taskspecific distractibility with promise of transfer to more efficient sporting performance in competitive contexts.

The Curvilinear Relationship between State Neuroticism and Momentary Task Performance

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Debusscher, Jonas; Hofmans, Joeri; De Fruyt, Filip

2014-01-01

A daily diary and two experience sampling studies were carried out to investigate curvilinearity of the within-person relationship between state neuroticism and task performance, as well as the moderating effects of within-person variation in momentary job demands (i.e., work pressure and task complexity). In one, results showed that under high work pressure, the state neuroticism–task performance relationship was best described by an exponentially decreasing curve, whereas an inverted U-shaped curve was found for tasks low in work pressure, while in another study, a similar trend was visible for task complexity. In the final study, the state neuroticism–momentary task performance relationship was a linear one, and this relationship was moderated by momentary task complexity. Together, results from all three studies showed that it is important to take into account the moderating effects of momentary job demands because within-person variation in job demands affects the way in which state neuroticism relates to momentary levels of task performance. Specifically, we found that experiencing low levels of state neuroticism may be most beneficial in high demanding tasks, whereas more moderate levels of state neuroticism are optimal under low momentary job demands. PMID:25238547

Rules and more rules: the effects of multiple tasks, extensive training, and aging on task-switching performance.

Science.gov (United States)

Buchler, Norbou G; Hoyer, William J; Cerella, John

2008-06-01

Task-switching performance was assessed in young and older adults as a function of the number of task sets to be actively maintained in memory (varied from 1 to 4) over the course of extended training (5 days). Each of the four tasks required the execution of a simple computational algorithm, which was instantaneously cued by the color of the two-digit stimulus. Tasks were presented in pure (task set size 1) and mixed blocks (task set sizes 2, 3, 4), and the task sequence was unpredictable. By considering task switching beyond two tasks, we found evidence for a cognitive control system that is not overwhelmed by task set size load manipulations. Extended training eliminated age effects in task-switching performance, even when the participants had to manage the execution of up to four tasks. The results are discussed in terms of current theories of cognitive control, including task set inertia and production system postulates.

Female but not male young heavy drinkers display altered performance monitoring.

Science.gov (United States)

Smith, Janette L; Mattick, Richard P; Sufani, Christopher

2015-09-30

Difficulties in monitoring ongoing behaviour may be linked to real-life problematic drinking behaviours. Prior research suggests female heavy drinkers in particular display greater cognitive control deficits. Here, we examine trial-to-trial behavioural adaptations in a conflict monitoring task, relative to drinking behaviour and sex. Heavy drinkers (n=31, 16 male) and controls (n=35, 18 male) completed an Eriksen flanker task while brain electrical activity was recorded. For reaction time, error rates, and N2 and P3 amplitude of the event-related potential, trial-to-trial conflict adaptation was evidenced by a differential response to the current (congruent vs. incongruent) trials dependent on the identity of the previous trial. For the proportion of errors, heavy drinkers showed increased conflict adaptation compared to controls. Conflict adaptation for N2 (indexing monitoring) was larger for female heavy drinkers than controls, and the opposite was observed for males. There were no interactions involving group or sex for the P3 (indexing inhibition). The results suggest a compensatory response, such that heavy drinkers are required to increase performance monitoring in order to achieve the same behavioural outcome as controls. We also confirm the importance of sex as a factor in the relationship between behavioural control and heavy alcohol use. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Selecting Tasks for Evaluating Human Performance as a Function of Gravity

Science.gov (United States)

Norcross, Jason R.; Gernhardt, Michael L.

2011-01-01

A challenge in understanding human performance as a function of gravity is determining which tasks to research. Initial studies began with treadmill walking, which was easy to quantify and control. However, with the development of pressurized rovers, it is less important to optimize human performance for ambulation as pressurized rovers will likely perform gross translation for them. Future crews are likely to spend much of their extravehicular activity (EVA) performing geology, construction,a nd maintenance type tasks. With these types of tasks, people have different performance strategies, and it is often difficult to quantify the task and measure steady-state metabolic rates or perform biomechanical analysis. For many of these types of tasks, subjective feedback may be the only data that can be collected. However, subjective data may not fully support a rigorous scientific comparison of human performance across different gravity levels and suit factors. NASA would benefit from having a wide variety of quantifiable tasks that allow human performance comparison across different conditions. In order to determine which tasks will effectively support scientific studies, many different tasks and data analysis techniques will need to be employed. Many of these tasks and techniques will not be effective, but some will produce quantifiable results that are sensitive enough to show performance differences. One of the primary concerns related to EVA performance is metabolic rate. The higher the metabolic rate, the faster the astronaut will exhaust consumables. The focus of this poster will be on how different tasks affect metabolic rate across different gravity levels.

Estimating the operator's performance time of emergency procedural tasks based on a task complexity measure

International Nuclear Information System (INIS)

Jung, Won Dae; Park, Jink Yun

2012-01-01

It is important to understand the amount of time required to execute an emergency procedural task in a high-stress situation for managing human performance under emergencies in a nuclear power plant. However, the time to execute an emergency procedural task is highly dependent upon expert judgment due to the lack of actual data. This paper proposes an analytical method to estimate the operator's performance time (OPT) of a procedural task, which is based on a measure of the task complexity (TACOM). The proposed method for estimating an OPT is an equation that uses the TACOM as a variable, and the OPT of a procedural task can be calculated if its relevant TACOM score is available. The validity of the proposed equation is demonstrated by comparing the estimated OPTs with the observed OPTs for emergency procedural tasks in a steam generator tube rupture scenario.

Age-related decrements in dual-task performance: Comparison of different mobility and cognitive tasks. A cross sectional study.

Science.gov (United States)

Brustio, Paolo Riccardo; Magistro, Daniele; Zecca, Massimiliano; Rabaglietti, Emanuela; Liubicich, Monica Emma

2017-01-01

This cross-sectional study investigated the age-related differences in dual-task performance both in mobility and cognitive tasks and the additive dual-task costs in a sample of older, middle-aged and young adults. 74 older adults (M = 72.63±5.57 years), 58 middle-aged adults (M = 46.69±4.68 years) and 63 young adults (M = 25.34±3.00 years) participated in the study. Participants performed different mobility and subtraction tasks under both single- and dual-task conditions. Linear regressions, repeated-measures and one-way analyses of covariance were used, The results showed: significant effects of the age on the dual and mobility tasks (ptask costs (pperformance under dual-task conditions in all groups (pperformance in the older group (ptask activity affected mobility and cognitive performance, especially in older adults who showed a higher dual-task cost, suggesting that dual-tasks activities are affected by the age and consequently also mobility and cognitive tasks are negatively influenced.

Operational testing of a figure of merit for overall task performance

Science.gov (United States)

Lemay, Moira

1990-01-01

An overall indicator or figure of merit (FOM), for the quality of pilot performance is needed to define optimal workload levels, predict system failure, measure the impact of new automation in the cockpit, and define the relative contributions of subtasks to overall task performance. A normative FOM was developed based on the calculation of a standard score for each component of a complex task. It reflected some effects, detailed in an earlier study, of the introduction of new data link technology into the cockpit. Since the technique showed promise, further testing was done. A new set of data was obtained using the recently developed Multi-Attribute Task Battery. This is a complex battery consisting of four tasks which can be varied in task demand, and on which performance measures can be obtained. This battery was presented to 12 subjects in a 20 minute trial at each of three levels of workload or task demand, and performance measures collected on all four tasks. The NASA-TLX workload rating scale was presented at minutes 6, 12, and 18, of each trial. A figure of merit was then obtained for each run of the battery by calculating a mean, SD, and standard score for each task. Each task contributed its own proportion to the overall FOM, and relative contributions changed with increasing workload. Thus, the FOM shows the effect of task changes, not only on the individual task that is changed, but also on the performance of other tasks and of the whole task. The cost to other tasks of maintaining constant performance on an individual task can be quantified.

Strategic predictors of performance in a divided attention task

Science.gov (United States)

Faragó, Kinga Bettina; Lőrincz, András

2018-01-01

In this study we investigate the strategies of subjects in a complex divided attention task. We conducted a series of experiments with ten participants and evaluated their performance. After an extensive analysis, we identified four strategic measures that justify the achievement of the participants, by highlighting the individual differences and predicting performance in a regression analysis using generalized estimating equations. Selecting the more urgent task and user action between multiple simultaneous possibilities form two of the strategic decisions, respectively. The third one refers to choosing a response within the same task when the opportunity is present. The fourth and most important measure of strategy involves thinking ahead and executing an action before a situation would become critical. This latter one has the effect of reducing later cognitive load or timing constraints and it is shown to explain almost as much variance in performance as the other three, more straightforward predictors together. In addition to determining these strategic predictors, we also show how manipulating task difficulty induces a shift in strategy, thus impairing human performance in the rehearsed task. The results of this study indicate that considerable differences in the divided attention ability of normal subjects can be identified early and with simple measurements. The importance of describing and analyzing strategies is also emphasized, which can substantially influence performance in complex tasks and may serve training needs. PMID:29621292

Strategic predictors of performance in a divided attention task.

Directory of Open Access Journals (Sweden)

Róbert Adrian Rill

Full Text Available In this study we investigate the strategies of subjects in a complex divided attention task. We conducted a series of experiments with ten participants and evaluated their performance. After an extensive analysis, we identified four strategic measures that justify the achievement of the participants, by highlighting the individual differences and predicting performance in a regression analysis using generalized estimating equations. Selecting the more urgent task and user action between multiple simultaneous possibilities form two of the strategic decisions, respectively. The third one refers to choosing a response within the same task when the opportunity is present. The fourth and most important measure of strategy involves thinking ahead and executing an action before a situation would become critical. This latter one has the effect of reducing later cognitive load or timing constraints and it is shown to explain almost as much variance in performance as the other three, more straightforward predictors together. In addition to determining these strategic predictors, we also show how manipulating task difficulty induces a shift in strategy, thus impairing human performance in the rehearsed task. The results of this study indicate that considerable differences in the divided attention ability of normal subjects can be identified early and with simple measurements. The importance of describing and analyzing strategies is also emphasized, which can substantially influence performance in complex tasks and may serve training needs.

Strategic predictors of performance in a divided attention task.

Science.gov (United States)

Rill, Róbert Adrian; Faragó, Kinga Bettina; Lőrincz, András

2018-01-01

In this study we investigate the strategies of subjects in a complex divided attention task. We conducted a series of experiments with ten participants and evaluated their performance. After an extensive analysis, we identified four strategic measures that justify the achievement of the participants, by highlighting the individual differences and predicting performance in a regression analysis using generalized estimating equations. Selecting the more urgent task and user action between multiple simultaneous possibilities form two of the strategic decisions, respectively. The third one refers to choosing a response within the same task when the opportunity is present. The fourth and most important measure of strategy involves thinking ahead and executing an action before a situation would become critical. This latter one has the effect of reducing later cognitive load or timing constraints and it is shown to explain almost as much variance in performance as the other three, more straightforward predictors together. In addition to determining these strategic predictors, we also show how manipulating task difficulty induces a shift in strategy, thus impairing human performance in the rehearsed task. The results of this study indicate that considerable differences in the divided attention ability of normal subjects can be identified early and with simple measurements. The importance of describing and analyzing strategies is also emphasized, which can substantially influence performance in complex tasks and may serve training needs.

Are factors related to dual-task performance in people with Parkinson's disease dependent on the type of dual task?

Science.gov (United States)

Strouwen, Carolien; Molenaar, Esther A L M; Keus, Samyra H J; Münks, Liesbeth; Heremans, Elke; Vandenberghe, Wim; Bloem, Bastiaan R; Nieuwboer, Alice

2016-02-01

Impaired dual-task performance significantly impacts upon functional mobility in people with Parkinson's disease (PD). The aim of this study was to identify determinants of dual-task performance in people with PD in three different dual tasks to assess their possible task-dependency. We recruited 121 home-dwelling patients with PD (mean age 65.93 years; mean disease duration 8.67 years) whom we subjected to regular walking (control condition) and to three dual-task conditions: walking combined with a backwards Digit Span task, an auditory Stroop task and a Mobile Phone task. We measured dual-task gait velocity using the GAITRite mat and dual-task reaction times and errors on the concurrent tasks as outcomes. Motor, cognitive and descriptive variables which correlated to dual-task performance (p task gait velocity and executive function, tested by the alternating intake test, was significantly associated with gait velocity during the Digit Span (R(2) = 0.65; p task (R(2) = 0.62; p task. Age was a surplus determinant of gait velocity while using a mobile phone. Single-task gait velocity and executive function as measured by a verbal fluency switching task were independent determinants of dual-task gait performance in people with PD. In contrast to expectation, these factors were the same across different tasks, supporting the robustness of the findings. Future study needs to determine whether these factors predict dual-task abnormalities prospectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Computer-mediated communication: task performance and satisfaction.

Science.gov (United States)

Simon, Andrew F

2006-06-01

The author assessed satisfaction and performance on 3 tasks (idea generation, intellective, judgment) among 75 dyads (N = 150) working through 1 of 3 modes of communication (instant messaging, videoconferencing, face to face). The author based predictions on the Media Naturalness Theory (N. Kock, 2001, 2002) and on findings from past researchers (e.g., D. M. DeRosa, C. Smith, & D. A. Hantula, in press) of the interaction between tasks and media. The present author did not identify task performance differences, although satisfaction with the medium was lower among those dyads communicating through an instant-messaging system than among those interacting face to face or through videoconferencing. The findings support the Media Naturalness Theory. The author discussed them in relation to the participants' frequent use of instant messaging and their familiarity with new communication media.

How do task characteristics affect learning and performance? The roles of variably mapped and dynamic tasks.

Science.gov (United States)

Macnamara, Brooke N; Frank, David J

2018-05-01

For well over a century, scientists have investigated individual differences in performance. The majority of studies have focused on either differences in practice, or differences in cognitive resources. However, the predictive ability of either practice or cognitive resources varies considerably across tasks. We are the first to examine task characteristics' impact on learning and performance in a complex task while controlling for other task characteristics. In 2 experiments we test key theoretical task characteristic thought to moderate the relationship between practice, cognitive resources, and performance. We devised a task where each of several key task characteristics can be manipulated independently. Participants played 5 rounds of a game similar to the popular tower defense videogame Plants vs. Zombies where both cognitive load and game characteristics were manipulated. In Experiment 1, participants either played a consistently mapped version-the stimuli and the associated meaning of their properties were constant across the 5 rounds-or played a variably mapped version-the stimuli and the associated meaning of their properties changed every few minutes. In Experiment 2, participants either played a static version-that is, turn taking with no time pressure-or played a dynamic version-that is, the stimuli moved regardless of participants' response rates. In Experiment 1, participants' accuracy and efficiency were substantially hindered in the variably mapped conditions. In Experiment 2, learning and performance accuracy were hindered in the dynamic conditions, especially when under cognitive load. Our results suggest that task characteristics impact the relative importance of cognitive resources and practice on predicting learning and performance. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Three-dimensional vision enhances task performance independently of the surgical method.

Science.gov (United States)

Wagner, O J; Hagen, M; Kurmann, A; Horgan, S; Candinas, D; Vorburger, S A

2012-10-01

Within the next few years, the medical industry will launch increasingly affordable three-dimensional (3D) vision systems for the operating room (OR). This study aimed to evaluate the effect of two-dimensional (2D) and 3D visualization on surgical skills and task performance. In this study, 34 individuals with varying laparoscopic experience (18 inexperienced individuals) performed three tasks to test spatial relationships, grasping and positioning, dexterity, precision, and hand-eye and hand-hand coordination. Each task was performed in 3D using binocular vision for open performance, the Viking 3Di Vision System for laparoscopic performance, and the DaVinci robotic system. The same tasks were repeated in 2D using an eye patch for monocular vision, conventional laparoscopy, and the DaVinci robotic system. Loss of 3D vision significantly increased the perceived difficulty of a task and the time required to perform it, independently of the approach (P robot than with laparoscopy (P = 0.005). In every case, 3D robotic performance was superior to conventional laparoscopy (2D) (P < 0.001-0.015). The more complex the task, the more 3D vision accelerates task completion compared with 2D vision. The gain in task performance is independent of the surgical method.

Manipulator Performance Evaluation Using Fitts' Taping Task

Energy Technology Data Exchange (ETDEWEB)

Draper, J.V.; Jared, B.C.; Noakes, M.W.

1999-04-25

Metaphorically, a teleoperator with master controllers projects the user's arms and hands into a re- mote area, Therefore, human users interact with teleoperators at a more fundamental level than they do with most human-machine systems. Instead of inputting decisions about how the system should func- tion, teleoperator users input the movements they might make if they were truly in the remote area and the remote machine must recreate their trajectories and impedance. This intense human-machine inter- action requires displays and controls more carefully attuned to human motor capabilities than is neces- sary with most systems. It is important for teleoperated manipulators to be able to recreate human trajectories and impedance in real time. One method for assessing manipulator performance is to observe how well a system be- haves while a human user completes human dexterity tasks with it. Fitts' tapping task has been, used many times in the past for this purpose. This report describes such a performance assessment. The International Submarine Engineering (ISE) Autonomous/Teleoperated Operations Manipulator (ATOM) servomanipulator system was evalu- ated using a generic positioning accuracy task. The task is a simple one but has the merits of (1) pro- ducing a performance function estimate rather than a point estimate and (2) being widely used in the past for human and servomanipulator dexterity tests. Results of testing using this task may, therefore, allow comparison with other manipulators, and is generically representative of a broad class of tasks. Results of the testing indicate that the ATOM manipulator is capable of performing the task. Force reflection had a negative impact on task efficiency in these data. This was most likely caused by the high resistance to movement the master controller exhibited with the force reflection engaged. Measurements of exerted forces were not made, so it is not possible to say whether the force reflection helped

Ranking Performance Measures in Multi-Task Agencies

DEFF Research Database (Denmark)

Christensen, Peter Ove; Sabac, Florin; Tian, Joyce

2010-01-01

We derive sufficient conditions for ranking performance evaluation systems in multi-task agency models (using both optimal and linear contracts) in terms of a second-order stochastic dominance (SSD) condition on the likelihood ratios. The SSD condition can be replaced by a variance-covariance mat......We derive sufficient conditions for ranking performance evaluation systems in multi-task agency models (using both optimal and linear contracts) in terms of a second-order stochastic dominance (SSD) condition on the likelihood ratios. The SSD condition can be replaced by a variance...

Task-dependent response conflict monitoring and cognitive control in anterior cingulate and dorsolateral prefrontal cortices.

Science.gov (United States)

Kim, Chobok; Chung, Chongwook; Kim, Jeounghoon

2013-11-06

Previous experience affects our behavior in terms of adjustments. It has been suggested that the conflict monitor-controller system implemented in the prefrontal cortex plays a critical role in such adjustments. Previous studies suggested that there exists multiple conflict monitor-controller systems associated with the level of information (i.e., stimulus and response levels). In this study, we sought to test whether different types of conflicts occur at the same information processing level (i.e., response level) are independently processed. For this purpose, we designed a task paradigm to measure two different types of response conflicts using color-based and location-based conflict stimuli and measured the conflict adaptation effects associated with the two types of conflicts either independently (i.e., single conflict conditions) or simultaneously (i.e., a double-conflict condition). The behavioral results demonstrated that performance on current incongruent trials was faster only when the preceding trial was the same type of response conflict regardless of whether they included a single- or double-conflict. Imaging data also showed that anterior cingulate and dorsolateral prefrontal cortices operate in a task-specific manner. These findings suggest that there may be multiple monitor-controller loops for color-based and location-based conflicts even at the same response level. Importantly, our results suggest that double-conflict processing is qualitatively different from single-conflict processing although double-conflict shares the same sources of conflict with two single-conflict conditions. © 2013 Published by Elsevier B.V.

A Study on Relationships between Functional Performance and Task Performance Measure through Experiments in NPP MCR

International Nuclear Information System (INIS)

Jang, In Seok; Seong, Poong Hyun; Park, Jin Kyun

2011-01-01

Further improvements in levels of organization, management, man-machine interfaces, education, training, etc. are required, if high operating reliability of operators in huge and complex plants such as chemical plants and electrical power generating plants is to be maintained. Improvement requires good understanding of operators' behavior, including defining what is good performance for operators, especially in emergency situations. Human performance measures, therefore, are important to enhance performance and to reduce the probability of incidents and accidents in Nuclear Power Plants (NPPs). Operators' performance measures are used for multi-objectives such as control room design, human system interface evaluation, training, procedure and so on. There are two kinds of representative methods to measure operators' performance. These methods are now known as the functional performance measure and task performance measure. Functional performance measures are basically based on the plant process parameters. Functional performance measures indicate how well the operators controlled selected critical parameters. The parameters selected in this paper are derived from the four Critical Safety Functions (CSFs) identified in the emergency operating procedures such as achievement of subcriticality, maintenance of core cooling, maintenance of heat sink and maintenance of containment integrity. Task performance measures are based on the task analysis. Task analysis is to determine the tasks required and how operators are performed. In this paper, task analysis is done with ideal path for an accident completed by experts and Emergency Operation Procedure (EOP). However, most literatures related to operators' performance have been using one of these measures and there is no research to find out the relationships between two measures. In this paper, the relationships between functional performance measure and task performance measure are investigated using experiments. Shortly

Workshift and Antihistamine Effects on Task Performance

National Research Council Canada - National Science Library

Gilliland, Kirby

1997-01-01

Sixteen male subjects, well trained on a battery of cognitive performance assessment tasks, participated in a study to Investigate the effects on human operator performance of work shift (Day Shift vs. Mid shift...

Task complexity and task, goal, and reward interdependence in group performance : a prescriptive model

NARCIS (Netherlands)

Vijfeijken, van H.T.G.A.; Kleingeld, P.A.M.; Tuijl, van H.F.J.M.; Algera, J.A.; Thierry, H.

2002-01-01

A prescriptive model on how to design effective combinations of goal setting and contingent rewards for group performance management is presented. The model incorporates the constructs task complexity, task interdependence, goal interdependence, and reward interdependence and specifies optimal fit

How different types of participant payments alter task performance

Directory of Open Access Journals (Sweden)

Gary L. Brase

2009-08-01

Full Text Available Researchers typically use incentives (such as money or course credit in order to obtain participants who engage in the specific behaviors of interest to the researcher. There is, however, little understanding or agreement on the effects of different types and levels of incentives used. Some results in the domain of statistical reasoning suggest that performance differences --- previously deemed theoretically important --- may actually be due to differences in incentive types across studies. 704 participants completed one of five variants of a statistical reasoning task, for which they received either course credit, flat fee payment, or performance-based payment incentives. Successful task completion was more frequent with performance-based incentives than with either of the other incentive types. Performance on moderately difficult tasks (compared to very easy and very hard tasks was most sensitive to incentives. These results can help resolve existing debates about inconsistent findings, guide more accurate comparisons across studies, and be applied beyond research settings.

The Effect of Cerebellar Transcranial Direct Current Stimulation on A Throwing Task Depends on Individual Level of Task Performance.

Science.gov (United States)

Mizuguchi, Nobuaki; Katayama, Takashi; Kanosue, Kazuyuki

2018-02-10

The effect of cerebellar transcranial direct current stimulation (tDCS) on motor performance remains controversial. Some studies suggest that the effect of tDCS depends upon task-difficulty and individual level of task performance. Here, we investigated whether the effect of cerebellar tDCS on the motor performance depends upon the individual's level of performance. Twenty-four naïve participants practiced dart throwing while receiving a 2-mA cerebellar tDCS for 20 min under three stimulus conditions (anodal-, cathodal-, and sham-tDCS) on separate days with a double-blind, counter-balanced cross-over design. Task performance was assessed by measuring the distance between the center of the bull's eye and the dart's position. Although task performance tended to improve throughout the practice under all stimulus conditions, improvement within a given day was not significant as compared to the first no-stimulus block. In addition, improvement did not differ among stimulation conditions. However, the magnitude of improvement was associated with an individual's level of task performance only under cathodal tDCS condition (p performance improvement only for the sub-group of participants with lower performance levels as compared to that with sham-tDCS (p task performance. Thus, cerebellar tDCS would facilitate learning of a complex motor skill task only in a subset of individuals. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Conflict monitoring and adjustment in the task-switching paradigm under different memory load conditions: an ERP/sLORETA analysis.

Science.gov (United States)

Deng, Yuqin; Wang, Yan; Ding, Xiaoqian; Tang, Yi-Yuan

2015-02-11

The aim of the present study was to examine electrophysiological and behavioral changes caused by different memory loads in a task-switching paradigm. A total of 31 healthy individuals were subjected to a task, in which the stimulus-response reversal paradigm was combined with the task-switching paradigm. The event-related potentials were recorded and the N2 component, an index of conflict processing, was measured. In addition, the neural sources of N2 were further analyzed by standardized low-resolution brain electromagnetic tomography. The event-related potential results showed that high memory load triggered a higher N2 mean amplitude. Moreover, the standardized low-resolution brain electromagnetic tomography data showed that high memory load caused an increase in current densities at the anterior cingulate cortex and the prefrontal cortex in the task-switching paradigm. In summary, our findings provide electrophysiological evidence to interpret possible influences of memory loads on conflict monitoring and modulation during the task switching. These results imply that the working memory load overrules the influence of task-switching performance on the intensification of cognitive control.

Performance in complex motor tasks deteriorates in hyperthermic humans

DEFF Research Database (Denmark)

Piil, Jacob Feder; Lundbye-Jensen, Jesper; Trangmar, Steven J

2017-01-01

-motor tracking performance was reduced by 10.7 ± 6.5% following exercise-induced hyperthermia when integrated in the multipart protocol and 4.4 ± 5.7% when tested separately (bothP 1.3% (P math tasks...... of information or decision-making prior to responding. We hypothesized that divergences could relate to task complexity and developed a protocol consisting of 1) simple motor task [TARGET_pinch], 2) complex motor task [Visuo-motor tracking], 3) simple math task [MATH_type], 4) combined motor-math task [MATH...

Task dynamics in self-organising task groups : expertise, motivational, and performance differences of specialists and generalists

NARCIS (Netherlands)

Zoethout, Kees; Jager, Wander; Molleman, Eric

Multi-agent simulation is applied to explore how different types of task variety cause workgroups to change their task allocation accordingly. We studied two groups, generalists and specialists. We hypothesised that the performance of the specialists would decrease when task variety increases. The

Is a Responsive Default Mode Network Required for Successful Working Memory Task Performance?

Science.gov (United States)

Čeko, Marta; Gracely, John L.; Fitzcharles, Mary-Ann; Seminowicz, David A.; Schweinhardt, Petra

2015-01-01

In studies of cognitive processing using tasks with externally directed attention, regions showing increased (external-task-positive) and decreased or “negative” [default-mode network (DMN)] fMRI responses during task performance are dynamically responsive to increasing task difficulty. Responsiveness (modulation of fMRI signal by increasing load) has been linked directly to successful cognitive task performance in external-task-positive regions but not in DMN regions. To investigate whether a responsive DMN is required for successful cognitive performance, we compared healthy human subjects (n = 23) with individuals shown to have decreased DMN engagement (chronic pain patients, n = 28). Subjects performed a multilevel working-memory task (N-back) during fMRI. If a responsive DMN is required for successful performance, patients having reduced DMN responsiveness should show worsened performance; if performance is not reduced, their brains should show compensatory activation in external-task-positive regions or elsewhere. All subjects showed decreased accuracy and increased reaction times with increasing task level, with no significant group differences on either measure at any level. Patients had significantly reduced negative fMRI response (deactivation) of DMN regions (posterior cingulate/precuneus, medial prefrontal cortex). Controls showed expected modulation of DMN deactivation with increasing task difficulty. Patients showed significantly reduced modulation of DMN deactivation by task difficulty, despite their successful task performance. We found no evidence of compensatory neural recruitment in external-task-positive regions or elsewhere. Individual responsiveness of the external-task-positive ventrolateral prefrontal cortex, but not of DMN regions, correlated with task accuracy. These findings suggest that a responsive DMN may not be required for successful cognitive performance; a responsive external-task-positive network may be sufficient

Administrative Task Performance by Heads of Senior High Schools ...

African Journals Online (AJOL)

This study aimed at examining the administrative task performance of heads of senior high schools (SHS) in Ghana from the organising perspective. The study hypothesized that there is no statistically significant difference in the compliance level of organising as an administrative task performance by heads in the rural and ...

How age affects memory task performance in clinically normal hearing persons.

Science.gov (United States)

Vercammen, Charlotte; Goossens, Tine; Wouters, Jan; van Wieringen, Astrid

2017-05-01

The main objective of this study is to investigate memory task performance in different age groups, irrespective of hearing status. Data are collected on a short-term memory task (WAIS-III Digit Span forward) and two working memory tasks (WAIS-III Digit Span backward and the Reading Span Test). The tasks are administered to young (20-30 years, n = 56), middle-aged (50-60 years, n = 47), and older participants (70-80 years, n = 16) with normal hearing thresholds. All participants have passed a cognitive screening task (Montreal Cognitive Assessment (MoCA)). Young participants perform significantly better than middle-aged participants, while middle-aged and older participants perform similarly on the three memory tasks. Our data show that older clinically normal hearing persons perform equally well on the memory tasks as middle-aged persons. However, even under optimal conditions of preserved sensory processing, changes in memory performance occur. Based on our data, these changes set in before middle age.

Effects of Class-Wide Self-Monitoring on On-Task Behaviors of Preschoolers with Developmental Disabilities

Science.gov (United States)

Kartal, Mine Sonmez; Ozkan, Serife Yucesoy

2015-01-01

The effects of class-wide self-monitoring on the on-task behaviors of preschoolers with developmental disabilities were determined. Also examined were whether the on-task behaviors of preschoolers with developmental disabilities had approximated the level of typically developing peers at the end of intervention, and classroom teachers and…

Motor-cognitive dual-task performance: effects of a concurrent motor task on distinct components of visual processing capacity.

Science.gov (United States)

Künstler, E C S; Finke, K; Günther, A; Klingner, C; Witte, O; Bublak, P

2018-01-01

Dual tasking, or the simultaneous execution of two continuous tasks, is frequently associated with a performance decline that can be explained within a capacity sharing framework. In this study, we assessed the effects of a concurrent motor task on the efficiency of visual information uptake based on the 'theory of visual attention' (TVA). TVA provides parameter estimates reflecting distinct components of visual processing capacity: perceptual threshold, visual processing speed, and visual short-term memory (VSTM) storage capacity. Moreover, goodness-of-fit values and bootstrapping estimates were derived to test whether the TVA-model is validly applicable also under dual task conditions, and whether the robustness of parameter estimates is comparable in single- and dual-task conditions. 24 subjects of middle to higher age performed a continuous tapping task, and a visual processing task (whole report of briefly presented letter arrays) under both single- and dual-task conditions. Results suggest a decline of both visual processing capacity and VSTM storage capacity under dual-task conditions, while the perceptual threshold remained unaffected by a concurrent motor task. In addition, goodness-of-fit values and bootstrapping estimates support the notion that participants processed the visual task in a qualitatively comparable, although quantitatively less efficient way under dual-task conditions. The results support a capacity sharing account of motor-cognitive dual tasking and suggest that even performing a relatively simple motor task relies on central attentional capacity that is necessary for efficient visual information uptake.

Functional near infrared spectroscopy of the sensory and motor brain regions with simultaneous kinematic and EMG monitoring during motor tasks.

Science.gov (United States)

Sukal-Moulton, Theresa; de Campos, Ana Carolina; Stanley, Christopher J; Damiano, Diane L

2014-12-05

There are several advantages that functional near-infrared spectroscopy (fNIRS) presents in the study of the neural control of human movement. It is relatively flexible with respect to participant positioning and allows for some head movements during tasks. Additionally, it is inexpensive, light weight, and portable, with very few contraindications to its use. This presents a unique opportunity to study functional brain activity during motor tasks in individuals who are typically developing, as well as those with movement disorders, such as cerebral palsy. An additional consideration when studying movement disorders, however, is the quality of actual movements performed and the potential for additional, unintended movements. Therefore, concurrent monitoring of both blood flow changes in the brain and actual movements of the body during testing is required for appropriate interpretation of fNIRS results. Here, we show a protocol for the combination of fNIRS with muscle and kinematic monitoring during motor tasks. We explore gait, a unilateral multi-joint movement (cycling), and two unilateral single-joint movements (isolated ankle dorsiflexion, and isolated hand squeezing). The techniques presented can be useful in studying both typical and atypical motor control, and can be modified to investigate a broad range of tasks and scientific questions.

Comparison of precision and speed in laparoscopic and robot-assisted surgical task performance.

Science.gov (United States)

Zihni, Ahmed; Gerull, William D; Cavallo, Jaime A; Ge, Tianjia; Ray, Shuddhadeb; Chiu, Jason; Brunt, L Michael; Awad, Michael M

2018-03-01

Robotic platforms have the potential advantage of providing additional dexterity and precision to surgeons while performing complex laparoscopic tasks, especially for those in training. Few quantitative evaluations of surgical task performance comparing laparoscopic and robotic platforms among surgeons of varying experience levels have been done. We compared measures of quality and efficiency of Fundamentals of Laparoscopic Surgery task performance on these platforms in novices and experienced laparoscopic and robotic surgeons. Fourteen novices, 12 expert laparoscopic surgeons (>100 laparoscopic procedures performed, no robotics experience), and five expert robotic surgeons (>25 robotic procedures performed) performed three Fundamentals of Laparoscopic Surgery tasks on both laparoscopic and robotic platforms: peg transfer (PT), pattern cutting (PC), and intracorporeal suturing. All tasks were repeated three times by each subject on each platform in a randomized order. Mean completion times and mean errors per trial (EPT) were calculated for each task on both platforms. Results were compared using Student's t-test (P task performance was slower on the robotic platform compared with laparoscopy. In comparisons of expert laparoscopists performing tasks on the laparoscopic platform and expert robotic surgeons performing tasks on the robotic platform, expert robotic surgeons demonstrated fewer errors during the PC task (P = 0.009). Robotic assistance provided a reduction in errors at all experience levels for some laparoscopic tasks, but no benefit in the speed of task performance. Robotic assistance may provide some benefit in precision of surgical task performance. Copyright © 2017 Elsevier Inc. All rights reserved.

Game elements improve performance in a working memory training task

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Manuel Ninaus

2015-02-01

Full Text Available The utilization of game elements in a non-game context is currently used in a vast range of different domains. However, research on game elements’ effects in cognitive tasks is still sparse. Thus, in this study we implemented three game elements, namely, progress bar, level indicator, and a thematic setting, in a working memory training task. We evaluated the impact of game elements on user performance and perceived state of flow when compared to a conventional version of the task. Participants interacting with game elements showed higher scores in the working memory training task than participants from a control group who completed the working memory training task without the game elements. Moreover, game elements facilitated the individuals’ performance closer to their maximum working memory capacity. Finally, the perceived flow did not differ between the two groups, which indicates that game elements can induce better performance without changing the perception of being “in the zone”, that is without an increase in anxiety or boredom. This empirical study indicates that certain game elements can improve the performance and efficiency in a working memory task by increasing users’ ability and willingness to train at their optimal performance level. 

Targeting Performance Dimensions in Sequence According to the Instructional Hierarchy: Effects on Children's Math Work within a Self-Monitoring Program

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Lannie, Amanda L.; Martens, Brian K.

2008-01-01

Four fifth-grade students were presented with frustration-level math probes while three performance dimensions were measured (i.e., percent intervals on-task, percent correct digits, and digits correct per minute (DCM)). Using a multiple baseline design across participants, students were trained to self-monitor time on-task, accuracy, and…

Continuous performance task in ADHD: Is reaction time variability a key measure?

Science.gov (United States)

Levy, Florence; Pipingas, Andrew; Harris, Elizabeth V; Farrow, Maree; Silberstein, Richard B

2018-01-01

To compare the use of the Continuous Performance Task (CPT) reaction time variability (intraindividual variability or standard deviation of reaction time), as a measure of vigilance in attention-deficit hyperactivity disorder (ADHD), and stimulant medication response, utilizing a simple CPT X-task vs an A-X-task. Comparative analyses of two separate X-task vs A-X-task data sets, and subgroup analyses of performance on and off medication were conducted. The CPT X-task reaction time variability had a direct relationship to ADHD clinician severity ratings, unlike the CPT A-X-task. Variability in X-task performance was reduced by medication compared with the children's unmedicated performance, but this effect did not reach significance. When the coefficient of variation was applied, severity measures and medication response were significant for the X-task, but not for the A-X-task. The CPT-X-task is a useful clinical screening test for ADHD and medication response. In particular, reaction time variability is related to default mode interference. The A-X-task is less useful in this regard.

High-performance execution of psychophysical tasks with complex visual stimuli in MATLAB

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Asaad, Wael F.; Santhanam, Navaneethan; McClellan, Steven

2013-01-01

Behavioral, psychological, and physiological experiments often require the ability to present sensory stimuli, monitor and record subjects' responses, interface with a wide range of devices, and precisely control the timing of events within a behavioral task. Here, we describe our recent progress developing an accessible and full-featured software system for controlling such studies using the MATLAB environment. Compared with earlier reports on this software, key new features have been implemented to allow the presentation of more complex visual stimuli, increase temporal precision, and enhance user interaction. These features greatly improve the performance of the system and broaden its applicability to a wider range of possible experiments. This report describes these new features and improvements, current limitations, and quantifies the performance of the system in a real-world experimental setting. PMID:23034363

Is a Responsive Default Mode Network Required for Successful Working Memory Task Performance?

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Čeko, Marta; Gracely, John L; Fitzcharles, Mary-Ann; Seminowicz, David A; Schweinhardt, Petra; Bushnell, M Catherine

2015-08-19

In studies of cognitive processing using tasks with externally directed attention, regions showing increased (external-task-positive) and decreased or "negative" [default-mode network (DMN)] fMRI responses during task performance are dynamically responsive to increasing task difficulty. Responsiveness (modulation of fMRI signal by increasing load) has been linked directly to successful cognitive task performance in external-task-positive regions but not in DMN regions. To investigate whether a responsive DMN is required for successful cognitive performance, we compared healthy human subjects (n = 23) with individuals shown to have decreased DMN engagement (chronic pain patients, n = 28). Subjects performed a multilevel working-memory task (N-back) during fMRI. If a responsive DMN is required for successful performance, patients having reduced DMN responsiveness should show worsened performance; if performance is not reduced, their brains should show compensatory activation in external-task-positive regions or elsewhere. All subjects showed decreased accuracy and increased reaction times with increasing task level, with no significant group differences on either measure at any level. Patients had significantly reduced negative fMRI response (deactivation) of DMN regions (posterior cingulate/precuneus, medial prefrontal cortex). Controls showed expected modulation of DMN deactivation with increasing task difficulty. Patients showed significantly reduced modulation of DMN deactivation by task difficulty, despite their successful task performance. We found no evidence of compensatory neural recruitment in external-task-positive regions or elsewhere. Individual responsiveness of the external-task-positive ventrolateral prefrontal cortex, but not of DMN regions, correlated with task accuracy. These findings suggest that a responsive DMN may not be required for successful cognitive performance; a responsive external-task-positive network may be sufficient. We studied the

Task-irrelevant auditory feedback facilitates motor performance in musicians

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Virginia eConde

2012-05-01

Full Text Available An efficient and fast auditory–motor network is a basic resource for trained musicians due to the importance of motor anticipation of sound production in musical performance. When playing an instrument, motor performance always goes along with the production of sounds and the integration between both modalities plays an essential role in the course of musical training. The aim of the present study was to investigate the role of task-irrelevant auditory feedback during motor performance in musicians using a serial reaction time task (SRTT. Our hypothesis was that musicians, due to their extensive auditory–motor practice routine during musical training, have a superior performance and learning capabilities when receiving auditory feedback during SRTT relative to musicians performing the SRTT without any auditory feedback. Here we provide novel evidence that task-irrelevant auditory feedback is capable to reinforce SRTT performance but not learning, a finding that might provide further insight into auditory-motor integration in musicians on a behavioral level.

An empirically derived figure of merit for the quality of overall task performance

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Lemay, Moira

1989-01-01

The need to develop an operationally relevant figure of merit for the quality of performance of a complex system such as an aircraft cockpit stems from a hypothesized dissociation between measures of performance and those of workload. Performance can be measured in terms of time, errors, or a combination of these. In most tasks performed by expert operators, errors are relatively rare and often corrected in time to avoid consequences. Moreover, perfect performance is seldom necessary to accomplish a particular task. Moreover, how well an expert performs a complex task consisting of a series of discrete cognitive tasks superimposed on a continuous task, such as flying an aircraft, does not depend on how well each discrete task is performed, but on their smooth sequencing. This makes the amount of time spent on each subtask of paramount importance in measuring overall performance, since smooth sequencing requires a minimum amount of time spent on each task. Quality consists in getting tasks done within a crucial time interval while maintaining acceptable continuous task performance. Thus, a figure of merit for overall quality of performance should be primarily a measure of time to perform discrete subtasks combined with a measure of basic vehicle control. Thus, the proposed figure of merit requires doing a task analysis on a series of performance, or runs, of a particular task, listing each discrete task and its associated time, and calculating the mean and standard deviation of these times, along with the mean and standard deviation of tracking error for the whole task. A set of simulator data on 30 runs of a landing task was obtained and a figure of merit will be calculated for each run. The figure of merit will be compared for voice and data link, so that the impact of this technology on total crew performance (not just communication performance) can be assessed. The effect of data link communication on other cockpit tasks will also be considered.

Performance monitoring in medication-naïve children with Tourette Syndrome

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Heike eEichele

2016-03-01

Full Text Available Background: Tourette syndrome (TS is a childhood-onset neurodevelopmental disorder and its impact on cognitive development needs further study. Evidence from neuropsychological, neuroimaging and electrophysiological studies suggest that the decline in tic severity and the ability to suppress tics relate to the development of self-regulatory functions in late childhood and adolescence. Hence, tasks measuring performance monitoring might provide insight into the regulation of tics in children with TS. Method: Twenty-five children with TS, including 14 with comorbid Attention-deficit/hyperactivity disorder (ADHD, 39 children with ADHD and 35 typically developing children aged 8-12 years were tested with a modified Eriksen-Flanker task during a 34-channel electroencephalography (EEG recording. Task performance, as well as stimulus-locked and response-locked event-related potentials (ERP were analyzed and compared across groups. Results: Participants did not differ in their behavioral performance. Children with TS showed higher amplitudes of an early P3 component of the stimulus-locked ERPs in ensemble averages and in separate trial outcomes, suggesting heightened orienting and/or attention during stimulus evaluation. In response-locked averages, children with TS had a slightly higher positive complex before the motor response, likely also reflecting a late P3. Groups did not differ in post-response components, particularly in the error-related negativity (ERN and error-related positivity (Pe.Conclusions: These findings suggest that children with TS may employ additional attentional resources as a compensatory mechanism to maintain equal behavioral performance.

Performance Monitoring in Medication-Naïve Children with Tourette Syndrome.

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Eichele, Heike; Eichele, Tom; Bjelland, Ingvar; Høvik, Marie F; Sørensen, Lin; van Wageningen, Heidi; Worren, Marius Kalsås; Hugdahl, Kenneth; Plessen, Kerstin J

2016-01-01

Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder and its impact on cognitive development needs further study. Evidence from neuropsychological, neuroimaging and electrophysiological studies suggests that the decline in tic severity and the ability to suppress tics relate to the development of self-regulatory functions in late childhood and adolescence. Hence, tasks measuring performance monitoring might provide insight into the regulation of tics in children with TS. Twenty-five children with TS, including 14 with comorbid Attention-deficit/ hyperactivity disorder (ADHD), 39 children with ADHD and 35 typically developing children aged 8-12 years were tested with a modified Eriksen-Flanker task during a 34-channel electroencephalography (EEG) recording. Task performance, as well as stimulus-locked and response-locked event-related potentials (ERP) were analyzed and compared across groups. Participants did not differ in their behavioral performance. Children with TS showed higher amplitudes of an early P3 component of the stimulus-locked ERPs in ensemble averages and in separate trial outcomes, suggesting heightened orienting and/or attention during stimulus evaluation. In response-locked averages, children with TS had a slightly higher positive complex before the motor response, likely also reflecting a late P3. Groups did not differ in post-response components, particularly in the error-related negativity (ERN) and error-related positivity (Pe). These findings suggest that children with TS may employ additional attentional resources as a compensatory mechanism to maintain equal behavioral performance.

Can tutoring improve performance on a reasoning task under deadline conditions?

Science.gov (United States)

Osman, Magda

2007-03-01

The present study examined the effectiveness of a tutoring technique that has been used to identify and address participants' misunderstandings in Wason's selection task. In particular, the study investigated whether the technique would lead to improvements in performance when the task was presented in a deadline format (a condition in which time restrictions are imposed). In Experiment 1, the effects of tutoring on performance were compared in free time (conditions in which no time restrictions are imposed) and deadline task formats. In Experiment 2, improvements in performance were studied in deadline task formats, in which the tutoring and test phases were separated by an interval of 1 day. The results suggested that tutoring improved performance on the selection task under deadline and in free time conditions. Additionally, the study showed that participants made errors because they had misinterpreted the task. With tutoring, they were able to modify their initial misunderstandings.

The Effect of Task Type and Pre-task Planning Condition on the Accuracy of Intermediate EFL Learners' Writing Performance

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Seyeed Mohammad Alavi

2012-05-01

Full Text Available Task-based language teaching, which requires learners to transact tasks resembling their real life language needs, demands language learners to perform planning at different stages of their learning. Since various types of tasks can be used in task-based instruction, the present study examined the effect of task types and various participatory structures during pre-task planning on the quality of learners' writing performance, (i.e., accuracy. Towards this end, 120 intermediate EFL students were randomly assigned to 3 experimental groups and one control group. While the experimental groups were subjected to different pre-task planning conditions, (i.e., individual, pair, and group, the control group performed tasks without any planning. During the treatment, they experienced task modeling, presentation and completion. A factorial design was followed in the present study, and the collected data were analyzed through ANOVAs that revealed task type and pre-task planning condition influenced the writing accuracy of the participants in a way that resulted in greater accuracy in the decision-making task in the experimental groups, thereby ensuring the effectiveness of the treatment in mitigating the long-standing problem of EFL learners in achieving higher levels of accuracy when a specific task type is concerned.

Predictors of operator performance at a simulated nuclear power plant control task

International Nuclear Information System (INIS)

Spettell, C.M.

1986-01-01

Male undergraduates participated in two experiments as operators of a simple dynamic nuclear power plant simulated on a personal computer. Their task involved monitoring the temperature and power output of the plant and controlling the flow of coolants and the position of the control rods to ensure that the plant operated at the desired temperature and output levels. Quality of performance was defined as the operator's ability to minimize the deviations in temperature and output from optimal values during the trials. Operator inputs and the status of all plant variables were recorded on-line every two seconds. Based on a review of human factors engineering and psychological literature, a number of personality, background, and process variables were measured and correlated with operator performance. Results of both experiments indicated that the strongest predictors of operator performance were the rate, magnitude, and accuracy of operator inputs. Input rate and magnitude were negatively related to overall performance; input accuracy was positively related to performance. These process variables and overall performance were relatively stable across trials of varying difficulty

Task complexity and task, goal, and reward interdependence in group performance management : A prescriptive model

NARCIS (Netherlands)

van Vijfeijken, H.; Kleingeld, A.; van Tuijl, H.; Algera, J.A.; Thierry, Hk.

2002-01-01

A prescriptive model on how to design effective combinations of goal setting and contingent rewards for group performance management is presented. The model incorporates the constructs task complexity, task interdependence, goal interdependence, and reward interdependence and specifies optimal fit

Effects of imperfect automation and individual differences on concurrent performance of military and robotics tasks in a simulated multitasking environment.

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Chen, J Y C; Terrence, P I

2009-08-01

This study investigated the performance and workload of the combined position of gunner and robotics operator in a simulated military multitasking environment. Specifically, the study investigated how aided target recognition (AiTR) capabilities for the gunnery task with imperfect reliability (false-alarm-prone vs. miss-prone) might affect the concurrent robotics and communication tasks. Additionally, the study examined whether performance was affected by individual differences in spatial ability and attentional control. Results showed that when the robotics task was simply monitoring the video, participants had the best performance in their gunnery and communication tasks and the lowest perceived workload, compared with the other robotics tasking conditions. There was a strong interaction between the type of AiTR unreliability and participants' perceived attentional control. Overall, for participants with higher perceived attentional control, false-alarm-prone alerts were more detrimental; for low attentional control participants, conversely, miss-prone automation was more harmful. Low spatial ability participants preferred visual cueing and high spatial ability participants favoured tactile cueing. Potential applications of the findings include personnel selection for robotics operation, robotics user interface designs and training development. The present results will provide further understanding of the interplays among automation reliability, multitasking performance and individual differences in military tasking environments. These results will also facilitate the implementation of robots in military settings and will provide useful data to military system designs.

Children's difficulty with true belief tasks: Competence deficit or performance problem?

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Oktay-Gür, Nese; Rakoczy, Hannes

2017-09-01

According to the standard picture of explicit theory of mind (ToM) development, children begin to (explicitly) ascribe beliefs to others and themselves from around age 4. The empirical basis of this picture comes from numerous studies consistently showing that children master verbal false belief (FB) tasks from around age 4 while children much younger have no difficulty in mastering structurally analogous true belief (TB) tasks. The standard picture, though, has come under serious attack from recent studies using TB tasks with wider age ranges. These studies have found that, paradoxically, children begin to fail TB tasks once they master FB tasks. Such findings cast doubt on the standard picture and suggest, instead, that FB tasks may be solved by much simpler strategies than proper belief reasoning. In the present study, we tested for the development of FB and TB performance in comprehensive and systematic ways. In particular, we tested the competing predictions of competence accounts (according to which TB failure reflects lack of conceptual competence) versus performance limitation accounts (according to which the standard picture is true yet children from around age 4 fail TB tasks due to performance factors). Studies 1 and 2 showed that performance in a variety of novel TB tasks showed a clear U-shaped curve, with children until age 3 and from age 10 performing competently and children in between failing, with strong negative correlations between TB and FB. Crucially, these patterns were found for various kinds of TB tasks, including those for which existing competence limitation accounts would not even predict any difficulty. Study 3, therefore, directly tested performance limitation accounts in terms of pragmatic and related factors and found that these patterns (failure in TB and negative TB-FB correlations) disappear once the relevant performance factors have been removed from the TB tasks. Taken together, these findings suggest that previous TB findings

Functional Task Test: 1. Sensorimotor changes Associated with Postflight Alterations in Astronaut Functional Task Performance

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Bloomberg, J. J.; Arzeno, N. H.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Platts, S. H.; Peters, B. T.;

Children's mathematical performance: five cognitive tasks across five grades.

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Moore, Alex M; Ashcraft, Mark H

2015-07-01

Children in elementary school, along with college adults, were tested on a battery of basic mathematical tasks, including digit naming, number comparison, dot enumeration, and simple addition or subtraction. Beyond cataloguing performance to these standard tasks in Grades 1 to 5, we also examined relationships among the tasks, including previously reported results on a number line estimation task. Accuracy and latency improved across grades for all tasks, and classic interaction patterns were found, for example, a speed-up of subitizing and counting, increasingly shallow slopes in number comparison, and progressive speeding of responses especially to larger addition and subtraction problems. Surprisingly, digit naming was faster than subitizing at all ages, arguing against a pre-attentive processing explanation for subitizing. Estimation accuracy and speed were strong predictors of children's addition and subtraction performance. Children who gave exponential responses on the number line estimation task were slower at counting in the dot enumeration task and had longer latencies on addition and subtraction problems. The results provided further support for the importance of estimation as an indicator of children's current and future mathematical expertise. Copyright © 2015 Elsevier Inc. All rights reserved.

Mental workload and cognitive task automaticity: an evaluation of subjective and time estimation metrics.

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Liu, Y; Wickens, C D

1994-11-01

The evaluation of mental workload is becoming increasingly important in system design and analysis. The present study examined the structure and assessment of mental workload in performing decision and monitoring tasks by focusing on two mental workload measurements: subjective assessment and time estimation. The task required the assignment of a series of incoming customers to the shortest of three parallel service lines displayed on a computer monitor. The subject was either in charge of the customer assignment (manual mode) or was monitoring an automated system performing the same task (automatic mode). In both cases, the subjects were required to detect the non-optimal assignments that they or the computer had made. Time pressure was manipulated by the experimenter to create fast and slow conditions. The results revealed a multi-dimensional structure of mental workload and a multi-step process of subjective workload assessment. The results also indicated that subjective workload was more influenced by the subject's participatory mode than by the factor of task speed. The time estimation intervals produced while performing the decision and monitoring tasks had significantly greater length and larger variability than those produced while either performing no other tasks or performing a well practised customer assignment task. This result seemed to indicate that time estimation was sensitive to the presence of perceptual/cognitive demands, but not to response related activities to which behavioural automaticity has developed.

Testing the Limits of Optimizing Dual-Task Performance in Younger and Older Adults

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Strobach, Tilo; Frensch, Peter; Müller, Herrmann Josef; Schubert, Torsten

2012-01-01

Impaired dual-task performance in younger and older adults can be improved with practice. Optimal conditions even allow for a (near) elimination of this impairment in younger adults. However, it is unknown whether such (near) elimination is the limit of performance improvements in older adults. The present study tests this limit in older adults under conditions of (a) a high amount of dual-task training and (b) training with simplified component tasks in dual-task situations. The data showed that a high amount of dual-task training in older adults provided no evidence for an improvement of dual-task performance to the optimal dual-task performance level achieved by younger adults. However, training with simplified component tasks in dual-task situations exclusively in older adults provided a similar level of optimal dual-task performance in both age groups. Therefore through applying a testing the limits approach, we demonstrated that older adults improved dual-task performance to the same level as younger adults at the end of training under very specific conditions. PMID:22408613

Providing global WLCG transfer monitoring

International Nuclear Information System (INIS)

Andreeva, J; Dieguez Arias, D; Campana, S; Keeble, O; Magini, N; Molnar, Z; Ro, G; Saiz, P; Salichos, M; Tuckett, D; Flix, J; Oleynik, D; Petrosyan, A; Uzhinsky, A; Wildish, T

2012-01-01

The WLCG[1] Transfers Dashboard is a monitoring system which aims to provide a global view of WLCG data transfers and to reduce redundancy in monitoring tasks performed by the LHC experiments. The system is designed to work transparently across LHC experiments and across the various technologies used for data transfer. Currently each LHC experiment monitors data transfers via experiment-specific systems but the overall cross-experiment picture is missing. Even for data transfers handled by FTS, which is used by 3 LHC experiments, monitoring tasks such as aggregation of FTS transfer statistics or estimation of transfer latencies are performed by every experiment separately. These tasks could be performed once, centrally, and then served to all experiments via a well-defined set of APIs. In the design and development of the new system, experience accumulated by the LHC experiments in the data management monitoring area is taken into account and a considerable part of the code of the ATLAS DDM Dashboard is being re-used. The paper describes the architecture of the Global Transfer monitoring system, the implementation of its components and the first prototype.

Context-Sensitive Adjustment of Cognitive Control in Dual-Task Performance

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Fischer, Rico; Gottschalk, Caroline; Dreisbach, Gesine

2014-01-01

Performing 2 highly similar tasks at the same time requires an adaptive regulation of cognitive control to shield prioritized primary task processing from between-task (cross-talk) interference caused by secondary task processing. In the present study, the authors investigated how implicitly and explicitly delivered information promotes the…

High-Performance Monitoring Architecture for Large-Scale Distributed Systems Using Event Filtering

Science.gov (United States)

Maly, K.

1998-01-01

Monitoring is an essential process to observe and improve the reliability and the performance of large-scale distributed (LSD) systems. In an LSD environment, a large number of events is generated by the system components during its execution or interaction with external objects (e.g. users or processes). Monitoring such events is necessary for observing the run-time behavior of LSD systems and providing status information required for debugging, tuning and managing such applications. However, correlated events are generated concurrently and could be distributed in various locations in the applications environment which complicates the management decisions process and thereby makes monitoring LSD systems an intricate task. We propose a scalable high-performance monitoring architecture for LSD systems to detect and classify interesting local and global events and disseminate the monitoring information to the corresponding end- points management applications such as debugging and reactive control tools to improve the application performance and reliability. A large volume of events may be generated due to the extensive demands of the monitoring applications and the high interaction of LSD systems. The monitoring architecture employs a high-performance event filtering mechanism to efficiently process the large volume of event traffic generated by LSD systems and minimize the intrusiveness of the monitoring process by reducing the event traffic flow in the system and distributing the monitoring computation. Our architecture also supports dynamic and flexible reconfiguration of the monitoring mechanism via its Instrumentation and subscription components. As a case study, we show how our monitoring architecture can be utilized to improve the reliability and the performance of the Interactive Remote Instruction (IRI) system which is a large-scale distributed system for collaborative distance learning. The filtering mechanism represents an Intrinsic component integrated

Method and Apparatus for Performance Optimization Through Physical Perturbation of Task Elements

Science.gov (United States)

Prinzel, Lawrence J., III (Inventor); Pope, Alan T. (Inventor); Palsson, Olafur S. (Inventor); Turner, Marsha J. (Inventor)

2016-01-01

The invention is an apparatus and method of biofeedback training for attaining a physiological state optimally consistent with the successful performance of a task, wherein the probability of successfully completing the task is made is inversely proportional to a physiological difference value, computed as the absolute value of the difference between at least one physiological signal optimally consistent with the successful performance of the task and at least one corresponding measured physiological signal of a trainee performing the task. The probability of successfully completing the task is made inversely proportional to the physiological difference value by making one or more measurable physical attributes of the environment in which the task is performed, and upon which completion of the task depends, vary in inverse proportion to the physiological difference value.

Perceived control in rhesus monkeys (Macaca mulatta) - Enhanced video-task performance

Science.gov (United States)

Washburn, David A.; Hopkins, William D.; Rumbaugh, Duane M.

1991-01-01

This investigation was designed to determine whether perceived control effects found in humans extend to rhesus monkeys (Macaca mulatta) tested in a video-task format, using a computer-generated menu program, SELECT. Choosing one of the options in SELECT resulted in presentation of five trials of a corresponding task and subsequent return to the menu. In Experiments 1-3, the animals exhibited stable, meaningful response patterns in this task (i.e., they made choices). In Experiment 4, performance on tasks that were selected by the animals significantly exceeded performance on identical tasks when assigned by the experimenter under comparable conditions (e.g., time of day, order, variety). The reliable and significant advantage for performance on selected tasks, typically found in humans, suggests that rhesus monkeys were able to perceive the availability of choices.

The effects of voice and manual control mode on dual task performance

Science.gov (United States)

Wickens, C. D.; Zenyuh, J.; Culp, V.; Marshak, W.

1986-01-01

Two fundamental principles of human performance, compatibility and resource competition, are combined with two structural dichotomies in the human information processing system, manual versus voice output, and left versus right cerebral hemisphere, in order to predict the optimum combination of voice and manual control with either hand, for time-sharing performance of a dicrete and continuous task. Eight right handed male subjected performed a discrete first-order tracking task, time-shared with an auditorily presented Sternberg Memory Search Task. Each task could be controlled by voice, or by the left or right hand, in all possible combinations except for a dual voice mode. When performance was analyzed in terms of a dual-task decrement from single task control conditions, the following variables influenced time-sharing efficiency in diminishing order of magnitude, (1) the modality of control, (discrete manual control of tracking was superior to discrete voice control of tracking and the converse was true with the memory search task), (2) response competition, (performance was degraded when both tasks were responded manually), (3) hemispheric competition, (performance degraded whenever two tasks were controlled by the left hemisphere) (i.e., voice or right handed control). The results confirm the value of predictive models invoice control implementation.

Neonatal Perirhinal Lesions in Rhesus Macaques Alter Performance on Working Memory Tasks with High Proactive Interference.

Science.gov (United States)

Weiss, Alison R; Nadji, Ryhan; Bachevalier, Jocelyne

2015-01-01

The lateral prefrontal cortex is known for its contribution to working memory (WM) processes in both humans and animals. Yet, recent studies indicate that the prefrontal cortex is part of a broader network of interconnected brain areas involved in WM. Within the medial temporal lobe (MTL) structures, the perirhinal cortex, which has extensive direct interactions with the lateral and orbital prefrontal cortex, is required to form active/flexible representations of familiar objects. However, its participation in WM processes has not be fully explored. The goal of this study was to assess the effects of neonatal perirhinal lesions on maintenance and monitoring WM processes. As adults, animals with neonatal perirhinal lesions and their matched controls were tested in three object-based (non-spatial) WM tasks that tapped different WM processing domains, e.g., maintenance only (Session-unique Delayed-nonmatching-to Sample, SU-DNMS), and maintenance and monitoring (Object-Self-Order, OBJ-SO; Serial Order Memory Task, SOMT). Neonatal perirhinal lesions transiently impaired the acquisition of SU-DNMS at a short (5 s) delay, but not when re-tested with a longer delay (30 s). The same neonatal lesions severely impacted acquisition of OBJ-SO task, and the impairment was characterized by a sharp increase in perseverative errors. By contrast, neonatal perirhinal lesion spared the ability to monitor the temporal order of items in WM as measured by the SOMT. Contrary to the SU-DNMS and OBJ-SO, which re-use the same stimuli across trials and thus produce proactive interference, the SOMT uses novel objects on each trial and is devoid of interference. Therefore, the impairment of monkeys with neonatal perirhinal lesions on SU-DNMS and OBJ-SO tasks is likely to be caused by an inability to solve working memory tasks with high proactive interference. The sparing of performance on the SOMT demonstrates that neonatal perirhinal lesions do not alter working memory processes per se but

Neonatal perirhinal lesions in rhesus macaques alter performance on working memory tasks with high proactive interference

Directory of Open Access Journals (Sweden)

Alison R Weiss

2016-01-01

Full Text Available The lateral prefrontal cortex is known for its contribution to working memory (WM processes in both humans and animals. Yet, recent studies indicate that the prefrontal cortex is part of a broader network of interconnected brain areas involved in WM. Within the medial temporal lobe structures, the perirhinal cortex, which has extensive direct interactions with the lateral and orbital prefrontal cortex, is required to form active/flexible representations of familiar objects. However, its participation in WM processes has not be fully explored. The goal of this study was to assess the effects of neonatal perirhinal lesions on maintenance and monitoring WM processes. As adults, animals with neonatal perirhinal lesions and their matched controls were tested in three object-based (non-spatial WM tasks that tapped different WM processing domains, e.g. maintenance only (Session-unique Delayed-nonmatching-to Sample, SU-DNMS, and maintenance and monitoring (Object-Self-Order, OBJ-SO; Serial Order Memory Task, SOMT. Neonatal perirhinal lesions transiently impaired the acquisition of SU-DNMS at a short (5s delay, but not when re-tested with a longer delay (30s. The same neonatal lesions severely impacted acquisition of OBJ-SO task, and the impairment was characterized by a sharp increase in perseverative errors. By contrast, neonatal perirhinal lesion spared the ability to monitor the temporal order of items in WM as measured by the SOMT. Contrary to the SU-DNMS and OBJ-SO, which re-use the same stimuli across trials and thus produce proactive interference, the SOMT uses novel objects on each trial and is devoid of interference. Therefore, the impairment of monkeys with neonatal perirhinal lesions on SU-DNMS and OBJ-SO tasks is likely to be caused by an inability to solve working memory tasks with high proactive interference. The sparing of performance on the SOMT demonstrates that neonatal perirhinal lesions do not alter working memory processes per se

Task-based incidental vocabulary learning in L2 Arabic: The role of proficiency and task performance

Directory of Open Access Journals (Sweden)

Ayman A. Mohamed

2016-03-01

Full Text Available This study tests the claim that word learning in a second language are contingent upon a task’s involvement load (i.e. the amount of need, search, and evaluation it imposes, as proposed by Laufer and Hulstijn (2001. Fifty-three English-speaking learners of Arabic were assigned to one of three vocabulary learning tasks that varied in the degree of involvement: reading comprehension with glosses (low, fill-in-the-gap task (medium, and sentence writing (high. Ten words, selected based on a pretest, were targeted in the tasks. Results showed a main effect of task, with the sentence writing task yielding the highest rates of vocabulary learning, followed by the gap-fill task, and finally the reading comprehension task. A significant correlation was found between accuracy of performance across participants and their subsequent vocabulary acquisition in the immediate posttest. Within groups, only the performance of the writing group correlated significantly with their posttest scores. Results of the present study validate the hypothesis and point to multiple factors at play in incidental vocabulary acquisition. The study provides further arguments to refine the hypothesis and implement pedagogical practices that accommodate incidental learning in foreign language settings.

Simulated laparoscopy using a head-mounted display vs traditional video monitor: an assessment of performance and muscle fatigue.

Science.gov (United States)

Maithel, S K; Villegas, L; Stylopoulos, N; Dawson, S; Jones, D B

2005-03-01

The direction of visual gaze may be an important ergonomic factor that affects operative performance. We designed a study to determine whether a head-mounted display (HMD) worn by the surgeon would improve task performance and/or reduce muscle fatigue during a laparoscopic task when compared to the use of a traditional video monitor display (VMD). Surgical residents (n = 30) were enrolled in the study. A junior group, consisting of 15 postgraduate year (PGY) = 1 subjects with no previous laparoscopic experience, and a senior group, consisting of 15 PGY 4 and PGY 5 subjects with experience, completed a laparoscopic task that was repeated four times using the Computer Enhanced Laparoscopic Training System (CELTS). Groups alternated between using the HMD with the task placed in a downward frontal position and the VMD with the task at a 30 degrees lateral angle. The CELTS module assessed task completion time, depth perception, path length of instruments, response orientation, motion smoothness; the system then generated an overall score. Electromyography (EMG) was used to record sternocleidomastoid muscle activity. Display preference was surveyed. The senior residents performed better than the junior residents overall on all parameters (p < 0.05) except for motion smoothness, where there was no difference. In both groups, the HMD significantly improved motion smoothness when compared to the VMD (p < 0.05). All other parameters were equal. There was less muscle fatigue when using the VMD (p < 0.05). We found that 66% of the junior residents but only 20% of the senior residents preferred the HMD. The CELTS module demonstrated evidence of construct validity by differentiating the performances of junior and senior residents. By aligning the surgeon's visual gaze with the instruments, HMD improved smoothness of motion. Experienced residents preferred the traditional monitor display. Although the VMD produced less muscle fatigue, inexperienced residents preferred the HMD

The Effect of Focus on Form and Task Complexity on L2 Learners' Oral Task Performance

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Salimi, Asghar

2015-01-01

Second Language learners' oral task performance has been one of interesting and research generating areas of investigations in the field of second language acquisition specially, task-based language teaching and learning. The main purpose of the present study is to investigate the effect of focus on form and task complexity on L2 learners' oral…

Age-related differences in dual task performance: A cross-sectional study on women.

Science.gov (United States)

Brustio, Paolo R; Magistro, Daniele; Rabaglietti, Emanuela; Liubicich, Monica E

2017-02-01

Simultaneous performances of motor and attention-demanding tasks are common in activities of everyday life. The present cross-sectional study examined the changes and age-related differences on mobility performance with an additional cognitive or motor task, and evaluated the relative dual-task cost (DTC) on the motor performance in young, middle-aged and older women. A total of 30 young (mean age 25.12 ± 3.00 years), 30 middle-aged (mean age 47.82 ± 5.06 years) and 30 older women (mean age 72.74 ± 5.95 years) were recruited. Participants carried out: (i) single task: Timed Up & Go Test; (ii) cognitive dual-task: Timed Up & Go Test while counting backwards by three; (iii) manual dual-task: Timed Up & Go Test while carrying a glass of water. A repeated measures anova with between-factor as age groups and within-factor as tasks was carried out to assess the effect of aging on the performance of mobility tasks. DTC was calculated as ([performance in single-task - performance in dual-task] / performance in single task) × 100%. One-way ancova were carried out to compare the DTC among the three age groups. A significant interaction between age groups and task (F 4,172  = 6.716, P performance under dual-task condition compared with young and middle-aged groups. Furthermore, DTC differences in cognitive task were observed in older women compared with younger and middle-aged women (F 2,86  = 7.649, P task. Dual-task conditions might affect mobility performance differently across the lifespan, and could be particularly challenging in older women. Geriatr Gerontol Int 2017; 17: 315-321. © 2015 Japan Geriatrics Society.

5 CFR 430.306 - Monitoring performance.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Monitoring performance. 430.306 Section 430.306 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERFORMANCE MANAGEMENT Managing Senior Executive Performance § 430.306 Monitoring performance. (a) Supervisors must...

Using Performance Task Data to Improve Instruction

Science.gov (United States)

Abbott, Amy L.; Wren, Douglas G.

2016-01-01

Two well-accepted ideas among educators are (a) performance assessment is an effective means of assessing higher-order thinking skills and (b) data-driven instruction planning is a valuable tool for optimizing student learning. This article describes a locally developed performance task (LDPT) designed to measure critical thinking, problem…

Pointing Device Performance in Steering Tasks.

Science.gov (United States)

Senanayake, Ransalu; Goonetilleke, Ravindra S

2016-06-01

Use of touch-screen-based interactions is growing rapidly. Hence, knowing the maneuvering efficacy of touch screens relative to other pointing devices is of great importance in the context of graphical user interfaces. Movement time, accuracy, and user preferences of four pointing device settings were evaluated on a computer with 14 participants aged 20.1 ± 3.13 years. It was found that, depending on the difficulty of the task, the optimal settings differ for ballistic and visual control tasks. With a touch screen, resting the arm increased movement time for steering tasks. When both performance and comfort are considered, whether to use a mouse or a touch screen for person-computer interaction depends on the steering difficulty. Hence, a input device should be chosen based on the application, and should be optimized to match the graphical user interface. © The Author(s) 2016.

Manipulating perceptual parameters in a continuous performance task.

Science.gov (United States)

Shalev, Nir; Humphreys, Glyn; Demeyere, Nele

2018-02-01

Sustained attention (SA) is among the most studied faculties of human cognition, and thought to be crucial for many aspects of behavior. Measuring SA often relies on performance on a continuous, low-demanding task. Such continuous performance tasks (CPTs) have many variations, and sustained attention is typically estimated based on variability in reaction times. While relying on reaction times may be useful in some cases, it can pose a challenge when working with clinical populations. To increase interpersonal variability in task parameters that do not rely on speed, researchers have increased demands for memory and response inhibition. These approaches, however, may be confounded when used to assess populations that suffer from multiple cognitive deficits. In the current study, we propose a new approach for increasing task variability by increasing the attentional demands. In order to do so, we created a new variation of a CPT - a masked version, where inattention is more likely to cause misidentifying a target. After establishing that masking indeed decreases target detection, we further investigated which task parameter may influence response biases. To do so, we contrasted two versions of the CPT with different target/distractor ratio. We then established how perceptual parameters can be controlled independently in a CPT. Following the experimental manipulations, we tested the MCCPT with aging controls and chronic stroke patients to assure the task can be used with target populations. The results confirm the MCCPT as a task providing high sensitivity without relying on reaction speed, and feasible for patients.

Conflicts between On-Task and Off-Task Behaviors in the Classroom: The Influences of Parental Monitoring, Peer Value Orientations, Students' Goals, and Their Value Orientations

Science.gov (United States)

Kilian, Britta; Hofer, Manfred; Kuhnle, Claudia

2013-01-01

Students in class are sometimes torn between following the lesson and engaging in off-task behavior. In this paper, instead of classifying it as a form of deviant behavior, off-task behavior is reconstructed as a manifestation of students multiple motivations in the classroom. The study examines whether parental monitoring, peer value…

Understanding the Impact of User Frustration Intensities on Task Performance Using the OCC Theory of Emotions

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Washington, Gloria

2012-01-01

Have you heard the saying "frustration is written all over your falce"? Well this saying is true, but that is not the only place. Frustration is written all over your face and your body. The human body has various means to communicate an emotion without the utterance of a single word. The Media Equation says that people interact with computers as if they are human: this includes experiencing frustration. This research measures frustration by monitoring human body-based measures such as heart rate, posture, skin temperature. and respiration. The OCC Theory of Emotions is used to separate frustration into different levels or intensities. The results of this study showed that individual intensities of frustration exist, so that task performance is not degraded. Results from this study can be used by usability testers to model how much frustration is needed before task performance measures start to decrease.

Shift Work and Cognitive Flexibility: Decomposing Task Performance.

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Cheng, Philip; Tallent, Gabriel; Bender, Thomas John; Tran, Kieulinh Michelle; Drake, Christopher L

2017-04-01

Deficits in cognitive functioning associated with shift work are particularly relevant to occupational performance; however, few studies have examined how cognitive functioning is associated with specific components of shift work. This observational study examined how circadian phase, nocturnal sleepiness, and daytime insomnia in a sample of shift workers ( N = 30) were associated with cognitive flexibility during the night shift. Cognitive flexibility was measured using a computerized task-switching paradigm, which produces 2 indexes of flexibility: switch cost and set inhibition. Switch cost represents the additional cognitive effort required in switching to a different task and can impact performance when multitasking is involved. Set inhibition is the efficiency in returning to previously completed tasks and represents the degree of cognitive perseveration, which can lead to reduced accuracy. Circadian phase was measured via melatonin assays, nocturnal sleepiness was assessed using the Multiple Sleep Latency Test, and daytime insomnia was assessed using the Insomnia Severity Index. Results indicated that those with an earlier circadian phase, insomnia, and sleepiness exhibited reduced cognitive flexibility; however, specific components of cognitive flexibility were differentially associated with circadian phase, insomnia, and sleepiness. Individuals with an earlier circadian phase (thus more misaligned to the night shift) exhibited larger switch costs, which was also associated with reduced task efficiency. Shift workers with more daytime insomnia demonstrated difficulties with cognitive inhibition, whereas nocturnal sleepiness was associated with difficulties in reactivating previous tasks. Deficits in set inhibition were also related to reduced accuracy and increased perseverative errors. Together, this study indicates that task performance deficits in shift work are complex and are variably impacted by different mechanisms. Future research may examine

Tasks of the Shipboard Independent Duty Hospital Corpsman. Task Training Adequacy and Performance Frequency.

Science.gov (United States)

1987-11-01

Frequency List E-1 Appendix F - Submarine Quick Reference Task Frequency List . F-1 0 Appendix G - Mean Performance...j~~~~~~, -,,-p.r.. ... .0 -. %... h. • - III APPENDIX E I SURFACE SHIP QUICK REFERENCE TASK FREQUENCY LIST A Q N E Dl It T T E A E H HI K I L L L1 L...34. - - - ----------------------------------------- ---.--- ---------------------- - - E-4 APPENDIX F " SUBMARINE QUICK REFERENCE TASK FREQUENCY LIST (N 1l0) "% R 0 W 4. A Q N E D R T T

An opportunity cost model of subjective effort and task performance

Science.gov (United States)

Kurzban, Robert; Duckworth, Angela; Kable, Joseph W.; Myers, Justus

2013-01-01

Why does performing certain tasks cause the aversive experience of mental effort and concomitant deterioration in task performance? One explanation posits a physical resource that is depleted over time. We propose an alternate explanation that centers on mental representations of the costs and benefits associated with task performance. Specifically, certain computational mechanisms, especially those associated with executive function, can be deployed for only a limited number of simultaneous tasks at any given moment. Consequently, the deployment of these computational mechanisms carries an opportunity cost – that is, the next-best use to which these systems might be put. We argue that the phenomenology of effort can be understood as the felt output of these cost/benefit computations. In turn, the subjective experience of effort motivates reduced deployment of these computational mechanisms in the service of the present task. These opportunity cost representations, then, together with other cost/benefit calculations, determine effort expended and, everything else equal, result in performance reductions. In making our case for this position, we review alternate explanations both for the phenomenology of effort associated with these tasks and for performance reductions over time. Likewise, we review the broad range of relevant empirical results from across subdisciplines, especially psychology and neuroscience. We hope that our proposal will help to build links among the diverse fields that have been addressing similar questions from different perspectives, and we emphasize ways in which alternate models might be empirically distinguished. PMID:24304775

Dual-task performance involving hand dexterity and cognitive tasks and daily functioning in people with schizophrenia: a pilot study.

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Lin, Keh-chung; Wu, Yi-fang; Chen, I-chen; Tsai, Pei-luen; Wu, Ching-yi; Chen, Chia-ling

2015-01-01

This study investigated separate and concurrent performance on cognitive and hand dexterity tasks and the relationship to daily functioning in 16 people with schizophrenia and 16 healthy control participants. Participants performed the Purdue Pegboard Test and the Serial Seven Subtraction Test under single- and dual-task conditions and completed two daily functioning evaluations. The hand dexterity of all participants declined in the dual-task condition, but the discrepancy between single-task and dual-task hand dexterity was greater in the schizophrenia group than in the control group (p.70, for all). The extent of discrepancy in hand dexterity was negatively correlated with daily functioning in the schizophrenia group (rs=-.3 to -.5, ps=.04-.26). Ability to perform dual tasks may be an indicator of daily functioning in people with schizophrenia. Use of dual-task training may be considered as a therapeutic activity with these clients. Copyright © 2015 by the American Occupational Therapy Association, Inc.

The Effect of Prior Task Success on Older Adults' Memory Performance: Examining the Influence of Different Types of Task Success.

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Geraci, Lisa; Hughes, Matthew L; Miller, Tyler M; De Forrest, Ross L

2016-01-01

Negative aging stereotypes can lead older adults to perform poorly on memory tests. Yet, memory performance can be improved if older adults have a single successful experience on a cognitive test prior to participating in a memory experiment (Geraci & Miller, 2013, Psychology and Aging, 28, 340-345). The current study examined the effects of different types of prior task experience on subsequent memory performance. Before participating in a verbal free recall experiment, older adults in Experiment 1 successfully completed either a verbal or a visual cognitive task or no task. In Experiment 2, they successfully completed either a motor task or no task before participating in the free recall experiment. Results from Experiment 1 showed that relative to control (no prior task), participants who had prior success, either on a verbal or a visual task, had better subsequent recall performance. Experiment 2 showed that prior success on a motor task, however, did not lead to a later memory advantage relative to control. These findings demonstrate that older adults' memory can be improved by a successful prior task experience so long as that experience is in a cognitive domain.

The influence of principal managerial task performance on ...

African Journals Online (AJOL)

Poor performance of managerial tasks culminates declining staff productivity and thus deteriorating students academic performance. Secondary school students performance in most public examinations are not satisfactory in most states in Nigeria. Hence, this study investigate the extent to which secondary school principal ...

Heat exchanger performance monitoring guidelines

International Nuclear Information System (INIS)

Stambaugh, N.; Closser, W. Jr.; Mollerus, F.J.

1991-12-01

Fouling can occur in many heat exchanger applications in a way that impedes heat transfer and fluid flow and reduces the heat transfer or performance capability of the heat exchanger. Fouling may be significant for heat exchanger surfaces and flow paths in contact with plant service water. This report presents guidelines for performance monitoring of heat exchangers subject to fouling. Guidelines include selection of heat exchangers to monitor based on system function, safety function and system configuration. Five monitoring methods are discussed: the heat transfer, temperature monitoring, temperature effectiveness, delta P and periodic maintenance methods. Guidelines are included for selecting the appropriate monitoring methods and for implementing the selected methods. The report also includes a bibliography, example calculations, and technical notes applicable to the heat transfer method

Effects of Task Performance and Task Complexity on the Validity of Computational Models of Attention

NARCIS (Netherlands)

Koning, L. de; Maanen, P.P. van; Dongen, K. van

2008-01-01

Computational models of attention can be used as a component of decision support systems. For accurate support, a computational model of attention has to be valid and robust. The effects of task performance and task complexity on the validity of three different computational models of attention were

Performance Trends During Sleep Deprivation on a Tilt-Based Control Task.

Science.gov (United States)

Bolkhovsky, Jeffrey B; Ritter, Frank E; Chon, Ki H; Qin, Michael

2018-07-01

Understanding human behavior under the effects of sleep deprivation allows for the mitigation of risk due to reduced performance. To further this goal, this study investigated the effects of short-term sleep deprivation using a tilt-based control device and examined whether existing user models accurately predict targeting performance. A task in which the user tilts a surface to roll a ball into a target was developed to examine motor performance. A model was built to predict human performance for this task under various levels of sleep deprivation. Every 2 h, 10 subjects completed the task until they reached 24 h of wakefulness. Performance measurements of this task, which were based on Fitts' law, included movement time, task throughput, and time intercept. The model predicted significant performance decrements over the 24-h period with an increase in movement time (R2 = 0.61), a decrease in throughput (R2 = 0.57), and an increase in time intercept (R2 = 0.60). However, it was found that in experimental trials there was no significant change in movement time (R2 = 0.11), throughput (R2 = 0.15), or time intercept (R2 = 0.27). The results found were unexpected as performance decrement is frequently reported during sleep deprivation. These findings suggest a reexamination of the initial thought of sleep loss leading to a decrement in all aspects of performance.Bolkovsky JB, Ritter FE, Chon KH, Qin M. Performance trends during sleep deprivation on a tilt-based control task. Aerosp Med Hum Perform. 2018; 89(7):626-633.

Sleep restriction during simulated wildfire suppression: effect on physical task performance.

Science.gov (United States)

Vincent, Grace; Ferguson, Sally A; Tran, Jacqueline; Larsen, Brianna; Wolkow, Alexander; Aisbett, Brad

2015-01-01

To examine the effects of sleep restriction on firefighters' physical task performance during simulated wildfire suppression. Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18) or a sleep restricted condition (4-hour sleep opportunity, n = 17). Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods. There were no differences between the sleep-restricted and control groups in firefighters' task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group. Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters' performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters' operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity.

Neuropharmacology of performance monitoring.

Science.gov (United States)

Jocham, Gerhard; Ullsperger, Markus

2009-01-01

Adaptive, goal-directed behavior requires that organisms evaluate their actions in terms of their outcomes. Neuroimaging studies show that unfavorable outcomes or situations with high level of conflict engage the posterior medial frontal cortex (pMFC). Recording of event-related potentials revealed that these situations are accompanied by a negative deflection, the so-called error-related negativity (ERN), which appears after an erroneous response or after negative feedback. Both activation of the pMFC and the ERN are thought to represent a signal that indicates the need for behavioral adjustment, and to recruit other brain regions that implement these adjustments. While many fMRI and EEG studies have shed light on the anatomical structures and the cognitive processes involved in performance monitoring, only very recently have researchers begun to investigate the underlying neurochemical mechanisms. Drawing on the putative involvement of dopamine (DA) neurons in coding a reward prediction error, an influential theory has ascribed a pivotal role to DA in performance monitoring. However, although important, DA is certainly not the only neuromodulator involved. Recent studies point to a role for serotonin, norepinephrine and GABA, but also for adenosine in performance monitoring. Here, we review the evidence for neurotransmitter effects on this function in humans. In this light, we critically discuss currently debated models of performance monitoring and potential alternatives.

A day in the life of a monitor!

Directory of Open Access Journals (Sweden)

Kunal Shah

2012-01-01

Full Text Available When at a site, the monitor will meet with the Study Coordinator, review the hospital medical records, use the internet database or paper to ′monitor′ their data versus their medical records, issue queries, check master files, count tablets or vials, provide the update to the doctor, and so on. When not traveling, the monitor will work in the office, printing letters, filing documents collected from sites, writing reports and follow-up letters, responding to e-mails, calling sites, to follow-up on the pending action items, in addition to calling sites not visited recently, attending study teleconferences, attending study and company training programs, reading standard operating procedures, completing excel spreadsheets or company specific software systems, and so on. The monitor is loaded with all these different types of work requirements and most importantly each and every task is important and time bound. Different skill sets are required for different tasks and the monitor plays different roles, while doing different tasks. This article enlists the tasks that are required to be done by the monitor, the different roles played by the monitor while doing these tasks, analyze which is the most important day for a monitor, what are the tasks performed during this day, and what knowledge and skills are required for performing these tasks.

Virtual street-crossing performance in persons with multiple sclerosis: Feasibility and task performance characteristics.

Science.gov (United States)

Stratton, M E; Pilutti, L A; Crowell, J A; Kaczmarski, H; Motl, R W

2017-01-02

Multiple sclerosis (MS) is a neurological disease that commonly results in physical and cognitive dysfunction. Accordingly, MS might impact the ability to safely cross the street. The purpose of this study was to examine the feasibility of a simulated street-crossing task in persons with MS and to determine differences in street-crossing performance between persons with MS and non-MS controls. 26 participants with MS (median Expanded Disability Status Scale [EDSS] score = 3.5) and 19 controls completed 40 trials of a virtual street-crossing task. There were 2 crossing conditions (i.e., no distraction and phone conversation), and participants performed 20 trials per condition. Participants were instructed that the goal of the task was to cross the street successfully (i.e., without being hit be a vehicle). The primary outcome was task feasibility, assessed as completion and adverse events. Secondary outcomes were measures of street-crossing performance. Overall, the simulated street-crossing task was feasible (i.e., 90% completion, no adverse events) in participants with MS. Participants with MS waited longer and were less attentive to traffic before entering the street compared with controls (all P .05). A virtual street-crossing task is feasible for studying street-crossing behavior in persons with mild MS and most individuals with moderate MS. Virtual street-crossing performance is impaired in persons with MS compared to controls; however, persons with MS do not appear to be more vulnerable to a distracting condition. The virtual reality environment presents a safe and useful setting for understanding pedestrian behavior in persons with MS.

Functional Task Test: 3. Skeletal Muscle Performance Adaptations to Space Flight

Science.gov (United States)

Ryder, Jeffrey W.; Wickwire, P. J.; Buxton, R. E.; Bloomberg, J. J.; Ploutz-Snyder, L.

2011-01-01

The functional task test is a multi-disciplinary study investigating how space-flight induced changes to physiological systems impacts functional task performance. Impairment of neuromuscular function would be expected to negatively affect functional performance of crewmembers following exposure to microgravity. This presentation reports the results for muscle performance testing in crewmembers. Functional task performance will be presented in the abstract "Functional Task Test 1: sensory motor adaptations associated with postflight alternations in astronaut functional task performance." METHODS: Muscle performance measures were obtained in crewmembers before and after short-duration space flight aboard the Space Shuttle and long-duration International Space Station (ISS) missions. The battery of muscle performance tests included leg press and bench press measures of isometric force, isotonic power and total work. Knee extension was used for the measurement of central activation and maximal isometric force. Upper and lower body force steadiness control were measured on the bench press and knee extension machine, respectively. Tests were implemented 60 and 30 days before launch, on landing day (Shuttle crew only), and 6, 10 and 30 days after landing. Seven Space Shuttle crew and four ISS crew have completed the muscle performance testing to date. RESULTS: Preliminary results for Space Shuttle crew reveal significant reductions in the leg press performance metrics of maximal isometric force, power and total work on R+0 (pperformance metrics were observed in returning Shuttle crew and these adaptations are likely contributors to impaired functional tasks that are ambulatory in nature (See abstract Functional Task Test: 1). Interestingly, no significant changes in central activation capacity were detected. Therefore, impairments in muscle function in response to short-duration space flight are likely myocellular rather than neuromotor in nature.

Consistency of performance of robot-assisted surgical tasks in virtual reality.

Science.gov (United States)

Suh, I H; Siu, K-C; Mukherjee, M; Monk, E; Oleynikov, D; Stergiou, N

2009-01-01

The purpose of this study was to investigate consistency of performance of robot-assisted surgical tasks in a virtual reality environment. Eight subjects performed two surgical tasks, bimanual carrying and needle passing, with both the da Vinci surgical robot and a virtual reality equivalent environment. Nonlinear analysis was utilized to evaluate consistency of performance by calculating the regularity and the amount of divergence in the movement trajectories of the surgical instrument tips. Our results revealed that movement patterns for both training tasks were statistically similar between the two environments. Consistency of performance as measured by nonlinear analysis could be an appropriate methodology to evaluate the complexity of the training tasks between actual and virtual environments and assist in developing better surgical training programs.

Ability of aphasic individuals to perform numerical processing and calculation tasks

Directory of Open Access Journals (Sweden)

Gabriela De Luccia

2014-03-01

Full Text Available Objective To compare performance on EC301 battery calculation task between aphasic subjects and normal controls of the same sex, age, and education. Method Thirty-two aphasic patients who had suffered a single left hemisphere stroke were evaluated. Forty-four healthy volunteers were also selected. All subjects underwent a comprehensive arithmetic battery to assess their numerical and calculation skills. Performances on numerical processing and calculation tasks were then analyzed. Results Aphasic individuals showed changes in their ability to perform numerical processing and calculation tasks that were not observed in the healthy population. Conclusion Compared with healthy subjects of the same age and education level, individuals with aphasia had difficulty performing various tasks that involved numerical processing and calculation.

Ramifications of single-port laparoscopic surgery: measuring differences in task performance using simulation.

Science.gov (United States)

Conway, Nathan E; Romanelli, John R; Bush, Ron W; Seymour, Neal E

2014-02-01

Single-port laparoscopic surgery imposes unique psychomotor challenges. We used surgical simulation to define performance differences between surgeons with and without single-port clinical experience and examined whether a short course of training resulted in improved performance. Study participants were assigned to 3 groups: resident group (RES), experienced laparoscopic surgeons with (SP) and without (LAP) prior single-port laparoscopic experience. Participants performed the Fundamentals of Laparoscopic Surgery precision cutting task on a ProMIS trainer through conventional ports or with articulating instruments via a SILS Port (Covidien, Inc). Two iterations of each method were performed. Then, 6 residents performed 10 successive single-port iterations to assess the effect of practice on task performance. The SP group had faster task times for both laparoscopic (P = .0486) and single-port (P = .0238) methods. The LAP group had longer path lengths for the single-port task than for the laparoscopic task (P = .03). The RES group was slower (P = .0019), with longer path length (P = .0010) but with greater smoothness (P = .0186) on the single-port task than the conventional laparoscopic task. Resident performance task time (P = .005) and smoothness (P = .045) improved with successive iterations. Our data show that surgeons with clinical single-port surgery experience perform a simulated single-port surgical task better than inexperienced single-port surgeons. Furthermore, this performance is comparable to that achieved with conventional laparoscopic techniques. Performance of residents declined dramatically when confronted with the challenges of the single-port task but improved with practice. These results suggest a role for lab-based single-port training.

Performance monitoring of safeguards equipment

International Nuclear Information System (INIS)

Sirisena, K.; Peltoranta, M.; Goussarov, V.; Vodrazka, P.

1999-01-01

SGTCS is responsible for monitoring and reporting the performance of the SG equipment. Performance monitoring (PM) has been implemented in most important safeguards equipment operating unattended in nuclear facilities. Inspectors acquire equipment performance data in facilities. After inspection, the data package is submitted to SGTCS for processing and analysis. The performance data is used for identification of systems or components, which should be changed in the field and for identification of modules which, should be diagnosed at HQ in order to determine the cause of failure. Moreover, the performance data is used for preventive maintenance and spares distribution planning, and to provide statistics for official reports and management decision making. An important part of the performance monitoring is reporting. Equipment performance reports contain information about equipment inventory, utilization, failure types, failure distribution, and reliability. Trends in performance are given in graphical form in cases, where past data is available. Reliability estimates such as expected times between failures are provided. The automated reporting tools are obtainable through EMIS database application. (author)

Co-Constructional Task Analysis: Moving beyond Adult-Based Models to Assess Young Children's Task Performance

Science.gov (United States)

Lee, Scott Weng Fai

2013-01-01

The assessment of young children's thinking competence in task performances has typically followed the novice-to-expert regimen involving models of strategies that adults use when engaged in cognitive tasks such as problem-solving and decision-making. Socio-constructivists argue for a balanced pedagogical approach between the adult and child that…

Identification of tasks performed by stroke patients using a mobility assistive device

DEFF Research Database (Denmark)

Hester, Todd; Sherrill, Delsey M; Hamel, Mathieu

2006-01-01

of these devices. In this study, we propose the use of wearable sensors to identify tasks performed by stroke patients with a mobility assistive device. Subjects performed ten tasks with a three-axis accelerometer attached to their ankle and a neural network was trained to identify the task being performed...... tasks associated with the use of a cane. Therefore, we envision that the methodology presented in this paper could be used to evaluate the use of a cane in the context of the task being performed........ Results from 15 stroke patients indicated that these motor tasks can be reliably identified with a median sensitivity of 90 % at a median specificity of 95%. These results indicate that it is possible to use a single module with a three-axis accelerometer attached to the ankle to reliably identify motor...

Automated Task Monitoring, Feedback and Training for Critical Missions

Data.gov (United States)

National Aeronautics and Space Administration — Engineers and astronauts on NASA missions must frequently follow lengthy and complex sets of directions to perform the tasks required of them. Missing or not...

Sleep restriction during simulated wildfire suppression: effect on physical task performance.

Directory of Open Access Journals (Sweden)

Grace Vincent

Full Text Available OBJECTIVES: To examine the effects of sleep restriction on firefighters' physical task performance during simulated wildfire suppression. METHODS: Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18 or a sleep restricted condition (4-hour sleep opportunity, n = 17. Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods. RESULTS: There were no differences between the sleep-restricted and control groups in firefighters' task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group. CONCLUSIONS: Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters' performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters' operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity.

Who does the public think should perform health care tasks?

Science.gov (United States)

Koteski, D R; McKinney, S

1988-10-01

The dietitian was identified as the most appropriate provider of such key nutrition services as nutrition assessment, determination of caloric requirements, provision of diet counseling, and prescription of diets. Several tasks fundamental to nutrition services were not viewed as highly suitable tasks for the dietitian, e.g., plan for care at home, monitor client progress, and check laboratory values. Activities that constitute key nutrition services need to be accentuated to clarify the numerous skills and extensive knowledge that dietitians possess. In the health care system of today, the dietetic profession must be associated with a wider range of health-related tasks than the traditional triad of diet, food, and hospital. Public relations and marketing strategies should focus on activities that provide the public with a clearer understanding of how the dietetic profession contributes to patient/client care.

Effects of Non-Driving Related Task Modalities on Takeover Performance in Highly Automated Driving.

Science.gov (United States)

Wandtner, Bernhard; Schömig, Nadja; Schmidt, Gerald

2018-04-01

Aim of the study was to evaluate the impact of different non-driving related tasks (NDR tasks) on takeover performance in highly automated driving. During highly automated driving, it is allowed to engage in NDR tasks temporarily. However, drivers must be able to take over control when reaching a system limit. There is evidence that the type of NDR task has an impact on takeover performance, but little is known about the specific task characteristics that account for performance decrements. Thirty participants drove in a simulator using a highly automated driving system. Each participant faced five critical takeover situations. Based on assumptions of Wickens's multiple resource theory, stimulus and response modalities of a prototypical NDR task were systematically manipulated. Additionally, in one experimental group, the task was locked out simultaneously with the takeover request. Task modalities had significant effects on several measures of takeover performance. A visual-manual texting task degraded performance the most, particularly when performed handheld. In contrast, takeover performance with an auditory-vocal task was comparable to a baseline without any task. Task lockout was associated with faster hands-on-wheel times but not altered brake response times. Results showed that NDR task modalities are relevant factors for takeover performance. An NDR task lockout was highly accepted by the drivers and showed moderate benefits for the first takeover reaction. Knowledge about the impact of NDR task characteristics is an enabler for adaptive takeover concepts. In addition, it might help regulators to make decisions on allowed NDR tasks during automated driving.

Performing Task Integration

DEFF Research Database (Denmark)

Elkjaer, Bente; Nickelsen, Niels Christian Mossfeldt

by shared goals and knowledge as well as mutual respect and frequent, timely, accurate and problem-solving ways of communication with the purpose of dealing with the tasks at hand in an integrated way. We introduce and discuss relational coordination theory through a case-study within public healthcare....... Here cross-professional coordination of work was done by scheduled communication twice a day. When we proposed a way for further integration of tasks through an all-inclusive team organization, we were met with resistance. We use the study to discuss whether relational coordination theory is able to do...... away with differences regarding task definitions and working conditions as well as professional knowledge hierarchies and responsibilities for parts and wholes....

Changes in Standing and Walking Performance Under Dual-Task Conditions Across the Lifespan.

Science.gov (United States)

Ruffieux, Jan; Keller, Martin; Lauber, Benedikt; Taube, Wolfgang

2015-12-01

Simultaneous performance of a postural and a concurrent task is rather unproblematic as long as the postural task is executed in an automatic way. However, in situations where postural control requires more central processing, cognitive resources may be exceeded by the addition of an attentionally demanding task. This may lead to interference between the two tasks, manifested in a decreased performance in one or both tasks (dual-task costs). Owing to changes in attentional demands of postural tasks as well as processing capacities across the lifespan, it might be assumed that dual-task costs are particularly pronounced in children and older adults probably leading to a U-shaped pattern for dual-task costs as a function of age. However, these changes in the ability of dual-tasking posture from childhood to old age have not yet been systematically reviewed. Therefore, Web of Science and PubMed databases were searched for studies comparing dual-task performance with one task being standing or walking in healthy groups of young adults and either children or older adults. Seventy-nine studies met inclusion criteria. For older adults, the expected increase in dual-task costs could be confirmed. In contrast, in children there was only feeble evidence for a trend towards enlarged dual-task costs. More good-quality studies comparing dual-task ability in children, young, and, ideally, also older adults within the same paradigm are needed to draw unambiguous conclusions about lifespan development of dual-task performance in postural tasks. There is evidence that, in older adults, dual-task performance can be improved by training. For the other age groups, these effects have yet to be investigated.

Highly automated driving, secondary task performance, and driver state.

Science.gov (United States)

Merat, Natasha; Jamson, A Hamish; Lai, Frank C H; Carsten, Oliver

2012-10-01

A driving simulator study compared the effect of changes in workload on performance in manual and highly automated driving. Changes in driver state were also observed by examining variations in blink patterns. With the addition of a greater number of advanced driver assistance systems in vehicles, the driver's role is likely to alter in the future from an operator in manual driving to a supervisor of highly automated cars. Understanding the implications of such advancements on drivers and road safety is important. A total of 50 participants were recruited for this study and drove the simulator in both manual and highly automated mode. As well as comparing the effect of adjustments in driving-related workload on performance, the effect of a secondary Twenty Questions Task was also investigated. In the absence of the secondary task, drivers' response to critical incidents was similar in manual and highly automated driving conditions. The worst performance was observed when drivers were required to regain control of driving in the automated mode while distracted by the secondary task. Blink frequency patterns were more consistent for manual than automated driving but were generally suppressed during conditions of high workload. Highly automated driving did not have a deleterious effect on driver performance, when attention was not diverted to the distracting secondary task. As the number of systems implemented in cars increases, an understanding of the implications of such automation on drivers' situation awareness, workload, and ability to remain engaged with the driving task is important.

Effects of force reflection on servomanipulator task performance

International Nuclear Information System (INIS)

Draper, J.V.; Moore, W.E.; Herndon, J.N.; Weil, B.S.

1986-01-01

This paper reports results of a testing program that assessed the impact of force reflection on servomanipulator task performance. The testing program compared three force-reflection levels: 4 to 1 (four units of force on the slave produce one unit of force at the master controller), 1 to 1, and infinity to 1 (no force reflection). Time required to complete tasks, rate of occurrence of errors, the maximum force applied to task components, and variability in forces during completion of representative remote handling tasks were used as dependent variables. Operators exhibited lower error rates, lower peak forces, and more consistent application of forces using force reflection than they did without it. These data support the hypothesis that force reflection provides useful information for servomanipulator operators

Monitoring-induced disruption in skilled typewriting.

Science.gov (United States)

Snyder, Kristy M; Logan, Gordon D

2013-10-01

It is often disruptive to attend to the details of one's expert performance. The current work presents four experiments that utilized a monitor to report protocol to evaluate the sufficiency of three accounts of monitoring-induced disruption. The inhibition hypothesis states that disruption results from costs associated with preparing to withhold inappropriate responses. The dual-task hypothesis states that disruption results from maintaining monitored information in working memory. The implicit-explicit hypothesis states that disruption results from explicitly monitoring details of performance that are normally implicit. The findings suggest that all three hypotheses are sufficient to produce disruption, but inhibition and dual-task costs are not necessary. Experiment 1 showed that monitoring to report was disruptive even when there was no requirement to inhibit. Experiment 2 showed that maintaining information in working memory caused some disruption but much less than monitoring to report. Experiment 4 showed that monitoring to inhibit was more disruptive than monitoring to report, suggesting that monitoring is more disruptive when it is combined with other task requirements, such as inhibition. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Thermal performance monitoring and optimisation

International Nuclear Information System (INIS)

Sunde, Svein; Berg; Oeyvind

1998-01-01

Monitoring of the thermal efficiency of nuclear power plants is expected to become increasingly important as energy-market liberalisation exposes plants to increasing availability requirements and fiercer competition. The general goal in thermal performance monitoring is straightforward: to maximise the ratio of profit to cost under the constraints of safe operation. One may perceive this goal to be pursued in two ways, one oriented towards fault detection and cost-optimal predictive maintenance, and another determined at optimising target values of parameters in response to any component degradation detected, changes in ambient conditions, or the like. Annual savings associated with effective thermal-performance monitoring are expected to be in the order of $ 100 000 for power plants of representative size. A literature review shows that a number of computer systems for thermal-performance monitoring exists, either as prototypes or commercially available. The characteristics and needs of power plants may vary widely, however, and decisions concerning the exact scope, content and configuration of a thermal-performance monitor may well follow a heuristic approach. Furthermore, re-use of existing software modules may be desirable. Therefore, we suggest here the design of a flexible workbench for easy assembly of an experimental thermal-performance monitor at the Halden Project. The suggested design draws heavily on our extended experience in implementing control-room systems featured by assets like high levels of customisation, flexibility in configuration and modularity in structure, and on a number of relevant adjoining activities. The design includes a multi-computer communication system and a graphical user's interface, and aims at a system adaptable to any combination of in-house or end user's modules, as well as commercially available software. (author)

Experimental evaluation of the influence of various rests on task performance

International Nuclear Information System (INIS)

Nagasaka, Akihiko; Hirose, Ayako

2000-01-01

This report deals with the result of the experiment that 8 subjects had executed adding task and search task. They executed each task in 80 minutes under 5 conditions: (1) with no rest, and with 4 kinds of 20 minutes rests, in which they (2) opened eyes, (3) closed eyes, (4) closed eyes with listening classic music and (5) closed eyes with feet massage, in the middle of the task. The results of analysis of variance with the task performance in the latter half, there were significant differences between each condition with every subject in adding task, and with 6 subjects in search task. However, the orders of the task performance with each condition were not the same by each subject. It was suggested that transition of the arousal levels under the rest was related to the effects of the rest rather than the subjects' taste in rests. In the rest, the percentage of α wave of electroencephalogram and the coefficient of variation of R-R interval (time interval of heart beats) were increased than in executing task. The mean Kendall's rank correlation of coefficient with the order of increase rate of α/β wave and the task performance in the latter half was slightly negative in adding task, but was about 0.4 in search task. From these results, about six requirements for 'an effective rest' were able to be mentioned, for example, 'the devices that raises the arousal levels is carried out just before a rest end'. (author)

Experimental evaluation of the influence of various rests on task performance

Energy Technology Data Exchange (ETDEWEB)

Nagasaka, Akihiko; Hirose, Ayako [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

2000-01-01

This report deals with the result of the experiment that 8 subjects had executed adding task and search task. They executed each task in 80 minutes under 5 conditions: (1) with no rest, and with 4 kinds of 20 minutes rests, in which they (2) opened eyes, (3) closed eyes, (4) closed eyes with listening classic music and (5) closed eyes with feet massage, in the middle of the task. The results of analysis of variance with the task performance in the latter half, there were significant differences between each condition with every subject in adding task, and with 6 subjects in search task. However, the orders of the task performance with each condition were not the same by each subject. It was suggested that transition of the arousal levels under the rest was related to the effects of the rest rather than the subjects' taste in rests. In the rest, the percentage of {alpha} wave of electroencephalogram and the coefficient of variation of R-R interval (time interval of heart beats) were increased than in executing task. The mean Kendall's rank correlation of coefficient with the order of increase rate of {alpha}/{beta} wave and the task performance in the latter half was slightly negative in adding task, but was about 0.4 in search task. From these results, about six requirements for 'an effective rest' were able to be mentioned, for example, 'the devices that raises the arousal levels is carried out just before a rest end'. (author)

Self-regulated learning processes of medical students during an academic learning task.

Science.gov (United States)

Gandomkar, Roghayeh; Mirzazadeh, Azim; Jalili, Mohammad; Yazdani, Kamran; Fata, Ladan; Sandars, John

2016-10-01

This study was designed to identify the self-regulated learning (SRL) processes of medical students during a biomedical science learning task and to examine the associations of the SRL processes with previous performance in biomedical science examinations and subsequent performance on a learning task. A sample of 76 Year 1 medical students were recruited based on their performance in biomedical science examinations and stratified into previous high and low performers. Participants were asked to complete a biomedical science learning task. Participants' SRL processes were assessed before (self-efficacy, goal setting and strategic planning), during (metacognitive monitoring) and after (causal attributions and adaptive inferences) their completion of the task using an SRL microanalytic interview. Descriptive statistics were used to analyse the means and frequencies of SRL processes. Univariate and multiple logistic regression analyses were conducted to examine the associations of SRL processes with previous examination performance and the learning task performance. Most participants (from 88.2% to 43.4%) reported task-specific processes for SRL measures. Students who exhibited higher self-efficacy (odds ratio [OR] 1.44, 95% confidence interval [CI] 1.09-1.90) and reported task-specific processes for metacognitive monitoring (OR 6.61, 95% CI 1.68-25.93) and causal attributions (OR 6.75, 95% CI 2.05-22.25) measures were more likely to be high previous performers. Multiple analysis revealed that similar SRL measures were associated with previous performance. The use of task-specific processes for causal attributions (OR 23.00, 95% CI 4.57-115.76) and adaptive inferences (OR 27.00, 95% CI 3.39-214.95) measures were associated with being a high learning task performer. In multiple analysis, only the causal attributions measure was associated with high learning task performance. Self-efficacy, metacognitive monitoring and causal attributions measures were associated

Development of Performance and ERPs in a Flanker Task in Children and Adolescents with Tourette Syndrome—A Follow-Up Study

Directory of Open Access Journals (Sweden)

Heike Eichele

2017-06-01

Full Text Available Background: Tourette Syndrome (TS is a neurodevelopmental disorder with childhood-onset, with a typical decline in tic severity, as well as an increasing ability to suppress tics in late childhood and adolescence. These processes develop in parallel with general improvement of self-regulatory abilities, and performance monitoring during this age-span. Hence, changes in performance monitoring over time might provide insight into the regulation of tics in children and adolescents with TS.Method: We measured reaction time, reaction time variability, accuracy, and event-related potentials (ERP in 17 children with TS, including 10 children with comorbid Attention-Deficit/Hyperactivity Disorder (ADHD, 24 children with ADHD, and 29 typically developing children, using a modified Eriksen Flanker task in two testing sessions administered on average 4.5 years apart. We then compared task performance, as well as ERP components across groups, and over time using regression models.Results: Task performance improved in all groups with age, and behavioral differences between children with TS and controls diminished at second assessment, while differences between controls and children with ADHD largely persisted. In terms of ERP, the early P3 developed earlier in children with TS compared with controls at the first assessment, but trajectories converged with maturation. ERP component amplitudes correlated with worst-ever tic scores.Conclusions: Merging trajectories between children with TS and controls are consistent with the development of compensatory self-regulation mechanisms during early adolescence, probably facilitating tic suppression, in contrast to children with ADHD. Correlations between ERP amplitudes and tic scores also support this notion.

Development of Performance and ERPs in a Flanker Task in Children and Adolescents with Tourette Syndrome—A Follow-Up Study

Science.gov (United States)

Eichele, Heike; Eichele, Tom; Marquardt, Lynn; Adolfsdottir, Steinunn; Hugdahl, Kenneth; Sørensen, Lin; Plessen, Kerstin J.

2017-01-01

Background: Tourette Syndrome (TS) is a neurodevelopmental disorder with childhood-onset, with a typical decline in tic severity, as well as an increasing ability to suppress tics in late childhood and adolescence. These processes develop in parallel with general improvement of self-regulatory abilities, and performance monitoring during this age-span. Hence, changes in performance monitoring over time might provide insight into the regulation of tics in children and adolescents with TS. Method: We measured reaction time, reaction time variability, accuracy, and event-related potentials (ERP) in 17 children with TS, including 10 children with comorbid Attention-Deficit/Hyperactivity Disorder (ADHD), 24 children with ADHD, and 29 typically developing children, using a modified Eriksen Flanker task in two testing sessions administered on average 4.5 years apart. We then compared task performance, as well as ERP components across groups, and over time using regression models. Results: Task performance improved in all groups with age, and behavioral differences between children with TS and controls diminished at second assessment, while differences between controls and children with ADHD largely persisted. In terms of ERP, the early P3 developed earlier in children with TS compared with controls at the first assessment, but trajectories converged with maturation. ERP component amplitudes correlated with worst-ever tic scores. Conclusions: Merging trajectories between children with TS and controls are consistent with the development of compensatory self-regulation mechanisms during early adolescence, probably facilitating tic suppression, in contrast to children with ADHD. Correlations between ERP amplitudes and tic scores also support this notion. PMID:28659750

Development of Performance and ERPs in a Flanker Task in Children and Adolescents with Tourette Syndrome-A Follow-Up Study.

Science.gov (United States)

Eichele, Heike; Eichele, Tom; Marquardt, Lynn; Adolfsdottir, Steinunn; Hugdahl, Kenneth; Sørensen, Lin; Plessen, Kerstin J

2017-01-01

Background: Tourette Syndrome (TS) is a neurodevelopmental disorder with childhood-onset, with a typical decline in tic severity, as well as an increasing ability to suppress tics in late childhood and adolescence. These processes develop in parallel with general improvement of self-regulatory abilities, and performance monitoring during this age-span. Hence, changes in performance monitoring over time might provide insight into the regulation of tics in children and adolescents with TS. Method: We measured reaction time, reaction time variability, accuracy, and event-related potentials (ERP) in 17 children with TS, including 10 children with comorbid Attention-Deficit/Hyperactivity Disorder (ADHD), 24 children with ADHD, and 29 typically developing children, using a modified Eriksen Flanker task in two testing sessions administered on average 4.5 years apart. We then compared task performance, as well as ERP components across groups, and over time using regression models. Results: Task performance improved in all groups with age, and behavioral differences between children with TS and controls diminished at second assessment, while differences between controls and children with ADHD largely persisted. In terms of ERP, the early P3 developed earlier in children with TS compared with controls at the first assessment, but trajectories converged with maturation. ERP component amplitudes correlated with worst-ever tic scores. Conclusions: Merging trajectories between children with TS and controls are consistent with the development of compensatory self-regulation mechanisms during early adolescence, probably facilitating tic suppression, in contrast to children with ADHD. Correlations between ERP amplitudes and tic scores also support this notion.

The trickle-down effect of predictability: Secondary task performance benefits from predictability in the primary task.

Directory of Open Access Journals (Sweden)

Magdalena Ewa Król

Full Text Available Predictions optimize processing by reducing attentional resources allocation to expected or predictable sensory data. Our study demonstrates that these saved processing resources can be then used on concurrent stimuli, and in consequence improve their processing and encoding. We illustrate this "trickle-down" effect with a dual task, where the primary task varied in terms of predictability. The primary task involved detection of a pre-specified symbol that appeared at some point of a short video of a dot moving along a random, semi-predictable or predictable trajectory. The concurrent secondary task involved memorization of photographs representing either emotionally neutral or non-neutral (social or threatening content. Performance in the secondary task was measured by a memory test. We found that participants allocated more attention to unpredictable (random and semi-predictable stimuli than to predictable stimuli. Additionally, when the stimuli in the primary task were more predictable, participants performed better in the secondary task, as evidenced by higher sensitivity in the memory test. Finally, social or threatening stimuli were allocated more "looking time" and a larger number of saccades than neutral stimuli. This effect was stronger for the threatening stimuli than social stimuli. Thus, predictability of environmental input is used in optimizing the allocation of attentional resources, which trickles-down and benefits the processing of concurrent stimuli.

The trickle-down effect of predictability: Secondary task performance benefits from predictability in the primary task.

Science.gov (United States)

Król, Magdalena Ewa; Król, Michał

2017-01-01

Predictions optimize processing by reducing attentional resources allocation to expected or predictable sensory data. Our study demonstrates that these saved processing resources can be then used on concurrent stimuli, and in consequence improve their processing and encoding. We illustrate this "trickle-down" effect with a dual task, where the primary task varied in terms of predictability. The primary task involved detection of a pre-specified symbol that appeared at some point of a short video of a dot moving along a random, semi-predictable or predictable trajectory. The concurrent secondary task involved memorization of photographs representing either emotionally neutral or non-neutral (social or threatening) content. Performance in the secondary task was measured by a memory test. We found that participants allocated more attention to unpredictable (random and semi-predictable) stimuli than to predictable stimuli. Additionally, when the stimuli in the primary task were more predictable, participants performed better in the secondary task, as evidenced by higher sensitivity in the memory test. Finally, social or threatening stimuli were allocated more "looking time" and a larger number of saccades than neutral stimuli. This effect was stronger for the threatening stimuli than social stimuli. Thus, predictability of environmental input is used in optimizing the allocation of attentional resources, which trickles-down and benefits the processing of concurrent stimuli.

Working memory in children predicts performance on a gambling task.

Science.gov (United States)

Audusseau, Jean; Juhel, Jacques

2015-01-01

The authors investigated whether working memory (WM) plays a significant role in the development of decision making in children, operationalized by the Children's Gambling Task (CGT). A total of 105 children aged 6-7, 8-9, and 10-11 years old carried out the CGT. Children aged 6-7 years old were found to have a lower performance than older children, which shows that the CGT is sensitive to participant's age. The hypothesis that WM plays a significant role in decision making was then tested following two approaches: (a) an experimental approach, comparing between groups the performance on the CGT in a control condition (the CGT only was administered) to that in a double task condition (participants had to carry out a recall task in addition to the CGT); (b) an interindividual approach, probing the relationship between CGT performance and performance on tasks measuring WM efficiency. The between-groups approach evidenced a better performance in the control group. Moreover, the interindividual approach showed that the higher the participants' WM efficiency was, the higher their performance in the CGT was. Taken together, these two approaches yield converging results that support the hypothesis that WM plays a significant role in decision making in children.

Evaluation of high-definition television for remote task performance

International Nuclear Information System (INIS)

Draper, J.V.; Fujita, Y.; Herndon, J.N.

1987-04-01

High-definition television (HDTV) transmits a video image with more than twice the number (1125 for HDTV to 525 for standard-resolution TV) of horizontal scan lines that standard-resolution TV provides. The improvement in picture quality (compared to standard-resolution TV) that the extra scan lines provide is impressive. Objects in the HDTV picture have more sharply defined edges, better contrast, and more accurate reproduction of shading and color patterns than do those in the standard-resolution TV picture. Because the TV viewing system is a key component for teleoperator performance, an improvement in TV picture quality could mean an improvement in the speed and accuracy with which teleoperators perform tasks. This report describes three experiments designed to evaluate the impact of HDTV on the performance of typical remote tasks. The performance of HDTV was compared to that of standard-resolution, monochromatic TV and standard-resolution, stereoscopic, monochromatic TV in the context of judgment of depth in a televised scene, visual inspection of an object, and performance of a typical remote handling task. The results of the three experiments show that in some areas HDTV can lead to improvement in teleoperator performance. Observers inspecting a small object for a flaw were more accurate with HDTV than with either of the standard-resolution systems. High resolution is critical for detection of small-scale flaws of the type in the experiment (a scratch on a glass bottle). These experiments provided an evaluation of HDTV television for use in tasks that must be routinely performed to remotely maintain a nuclear fuel reprocessing facility. 5 refs., 7 figs., 9 tabs

Attention Deficit ِDuring Dual-Task Performance in Alzheimer’s Disease Patients

Directory of Open Access Journals (Sweden)

Hamid Salehi

2014-07-01

Full Text Available Objectives: The aims of the present investigation was the evaluation of divided attention deficits in Alzheimer's disease (AD patients by using dual-task paradigm in order to ascertain whether this method can be useful in the early diagnosis of AD or not.  Methods & Materials: A total of 23 elderly individuals (11 females and 12 males voluntarily participated in the investigation: 13 patients with Alzheimer's disease (AD and 10 healthy elderly individuals. The experimental setup consisted of (a single -task and (b dual-task trials at two levels of difficulty. In singletask condition, the participants were asked to recite the months of the year continuously with normal order (easy and backward (difficult. They also performed a computerized visuospatial/motor tracking task. The participants then performed the tracking task in conjunction with each of the months reciting tasks as dual-task condition. Results: The results showed a significant interaction (disease×level of difficulty effect. So that, the performance impairment on combine performance in two simultaneous tasks was related to task difficulty, but the elderly control group did not differ in the easy and difficult conditions. Conclusion: These findings not only increase our understanding of the attention deficits in AD patients, but also have implications for the mediating effect of cognitive load in using dual-task paradigm for studying attention mechanisms of cognitively suffered individuals.

Engineering Task Plan for Fourth Generation Hanford Corrosion Monitoring System

International Nuclear Information System (INIS)

NORMAN, E.C.

2000-01-01

This Engineering Task Plan (ETP) describes the activities associated with the installation of cabinets containing corrosion monitoring equipment on tanks 241-AN-102 and 241-AN-107. The new cabinets (one per tank) will be installed adjacent to existing corrosion probes already installed in riser WST-RISER-016 on both tanks. The corrosion monitoring equipment to be installed utilizes the technique of electrochemical noise (EN) for monitoring waste tank corrosion. Typically, EN consists of low frequency (4 Hz) and small amplitude signals that are spontaneously generated by electrochemical reactions occurring at corroding or other surfaces. EN analysis is well suited for monitoring and identifying the onset of localized corrosion, and for measuring uniform corrosion rates. A typical EN based corrosion-monitoring system measures instantaneous fluctuations in corrosion current and potential between three nominally identical electrodes of the material of interest immersed in the environment of interest. Time-dependent fluctuations in corrosion current are described by electrochemical current noise, and time-dependent fluctuations of corrosion potential are described by electrochemical noise. The corrosion monitoring systems are designed to detect the onset of localized corrosion phenomena if tank conditions should change to allow these phenomena to occur. In addition to the EN technique, the systems also facilitate the use of the Linear Polarization Resistance (LPR) technique to collect uniform corrosion rate information. LPR measures the linearity at the origin of the polarization curve for overvoltages up to a few millivolts away from the rest potential or natural corrosion potential. The slope of the current vs. voltage plot gives information on uniform corrosion rates

Combined factors effect of menstrual cycle and background noise on visual inspection task performance: a simulation-based task.

Science.gov (United States)

Wijayanto, Titis; Tochihara, Yutaka; Wijaya, Andi R; Hermawati, Setia

2009-11-01

It is well known that women are physiologically and psychologically influenced by the menstrual cycle. In addition, the presence of background noise may affect task performance. So far, it has proven difficult to describe how the menstrual cycle and background noise affect task performance; some researchers have found an increment of performance during menstruation or during the presence of noise, others found performance deterioration, while other still have reported no dominant effect either of the menstrual cycle in performance or of the presence of noise. However, no study to date has investigated the combinational effect between the menstrual cycle and the presence of background noise in task performance. Therefore, the purpose of this study was to examine the combined factor effect of menstrual cycle and background noise on visual inspection task performance indices by Signal Detection Theory (SDT) metrics: sensitivity index (d') and response criteria index (beta). For this purpose, ten healthy female students (21.5+/-1.08 years) with a regular menstrual cycle participated in this study. A VDT-based visual inspection task was used for the experiment in 3x2 factorial designs. Two factors, menstrual phase, pre-menstruation (PMS), menstruation (M), and post-menstruation (PM) and background noise, with 80 dB(A) background noise and without noise, were analyzed as the main factors in this study. The results concluded that the sensitivity index (d') of SDT was affected in all the menstrual cycle conditions (pbackground noise (pbackground noise was found in this study. On the other hand, no significant effect was observed in the subject's tendency in visual inspection, shown by beta along the menstrual cycle and the presence of background noise. According to the response criteria for each individual subject, the presence of noise affected the tendency of some subjects in detecting the object and making decision during the visual inspection task.

San Joaquin River Up-Stream DO TMDL Project Task 4: MonitoringStudy Interim Task Report #3

Energy Technology Data Exchange (ETDEWEB)

Stringfellow, William; Borglin, Sharon; Dahlgren, Randy; Hanlon,Jeremy; Graham, Justin; Burks, Remie; Hutchinson, Kathleen

2007-03-30

Lander Avenue.This data is specifically being collected to provide data for the Task 6Modeling effort. Task 4 provides input and calibration data for flow andWQ modeling associated with the low DO problems in the SJR watershed,including modeling on the linkage among nutrients, algae, and low DO.Task 4 is providing a higher volume of high quality and coherent data tothe modeling team than was available in the past for the upstream SJR.The monitoring and research activities under Task 4 are integrated withthe Modeling effort (Task 6) and are not designed to be a stand aloneprogram. Although, the majority of analysis of the Task 4 data isoccurring as part of the Task 6 Modeling program, analysis of Task 4 dataindependently of the modeling effort is also an important component ofthe DO TMDL Project effort. In this report, we present the results ofmonitoring and research conducted under Task 4. The major purposes ofthis report are to 1) document activities undertaken as part of theDOTMDL Project; 2) organize electronic data for delivery to Stateagencies, stakeholders and principal investigators (cooperators) on theDO TMDL Project; 3) provide a summary analysis of the data for referenceand to assist stakeholders in planning watershed activities inresponse tothe DO TMDL requirements; and 5) provide a preliminary scientificinterpretation independently of the Task 6 Modeling effort. Due to theextensive scope of theTask 4 portion of the DO TMDL Project, the Task 4March 2007 Interim Report is divided into a numbers of chapters andassociated appendixes designed to be able to stand1-3 independently ofeach other. The purpose of this chapter is to provide an overview of Task4 data collection and to explain the structure of the overallreport.

JACoW Automatic PID performance monitoring applied to LHC cryogenics

CERN Document Server

Bradu, Benjamin; Marti, Ruben; Tilaro, Filippo

2018-01-01

At CERN, the LHC (Large Hadron Collider) cryogenic system employs about 5000 PID (Proportional Integral Derivative) regulation loops distributed over the 27 km of the accelerator. Tuning all these regulation loops is a complex task and the systematic monitoring of them should be done in an automated way to be sure that the overall plant performance is improved by identifying the poorest performing PID controllers. It is nearly impossible to check the performance of a regulation loop with a classical threshold technique as the controlled variables could evolve in large operation ranges and the amount of data cannot be manually checked daily. This paper presents the adaptation and the application of an existing regulation indicator performance algorithm on the LHC cryogenic system and the different results obtained in the past year of operation. This technique is generic for any PID feedback control loop, it does not use any process model and needs only a few tuning parameters. The publication also describes th...

The Neurocognitive Basis for Impaired Dual-Task Performance in Senior Fallers.

Science.gov (United States)

Nagamatsu, Lindsay S; Hsu, C Liang; Voss, Michelle W; Chan, Alison; Bolandzadeh, Niousha; Handy, Todd C; Graf, Peter; Beattie, B Lynn; Liu-Ambrose, Teresa

2016-01-01

Falls are a major health-care concern, and while dual-task performance is widely recognized as being impaired in those at-risk for falls, the underlying neurocognitive mechanisms remain unknown. A better understanding of the underlying mechanisms could lead to the refinement and development of behavioral, cognitive, or neuropharmacological interventions for falls prevention. Therefore, we conducted a cross-sectional study with community-dwelling older adults aged 70-80 years with a history of falls (i.e., two or more falls in the past 12 months) or no history of falls (i.e., zero falls in the past 12 months); n = 28 per group. We compared functional activation during cognitive-based dual-task performance between fallers and non-fallers using functional magnetic resonance imaging (fMRI). Executive cognitive functioning was assessed via Stroop, Trail Making, and Digit Span. Mobility was assessed via the Timed Up and Go test (TUG). We found that non-fallers exhibited significantly greater functional activation compared with fallers during dual-task performance in key regions responsible for resolving dual-task interference, including precentral, postcentral, and lingual gyri. Further, we report slower reaction times during dual-task performance in fallers and significant correlations between level of functional activation and independent measures of executive cognitive functioning and mobility. Our study is the first neuroimaging study to examine dual-task performance in fallers, and supports the notion that fallers have reduced functional brain activation compared with non-fallers. Given that dual-task performance-and the underlying neural concomitants-appears to be malleable with relevant training, our study serves as a launching point for promising strategies to reduce falls in the future.

Increasing Optimism Protects Against Pain-Induced Impairment in Task-Shifting Performance.

Science.gov (United States)

Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

2017-04-01

Persistent pain can lead to difficulties in executive task performance. Three core executive functions that are often postulated are inhibition, updating, and shifting. Optimism, the tendency to expect that good things happen in the future, has been shown to protect against pain-induced performance deterioration in executive function updating. This study tested whether this protective effect of a temporary optimistic state by means of a writing and visualization exercise extended to executive function shifting. A 2 (optimism: optimism vs no optimism) × 2 (pain: pain vs no pain) mixed factorial design was conducted. Participants (N = 61) completed a shifting task once with and once without concurrent painful heat stimulation after an optimism or neutral manipulation. Results showed that shifting performance was impaired when experimental heat pain was applied during task execution, and that optimism counteracted pain-induced deterioration in task-shifting performance. Experimentally-induced heat pain impairs shifting task performance and manipulated optimism or induced optimism counteracted this pain-induced performance deterioration. Identifying psychological factors that may diminish the negative effect of persistent pain on the ability to function in daily life is imperative. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

Task feedback effects on conflict monitoring and executive control: relationship to subclinical measures of depression.

Science.gov (United States)

Holmes, Avram J; Pizzagalli, Diego A

2007-02-01

Emerging evidence suggests that depression is associated with executive dysfunction, particularly after committing errors or receiving negative performance feedback. To test this hypothesis, 57 participants performed two executive tasks known to elicit errors (the Simon and Stroop Tasks) during positive or negative performance feedback. Participants with elevated depressive symptoms (Beck Depression Inventory scores >or= 13) were characterized by impaired posterror and postconflict performance adjustments, especially during emotionally negative task-related feedback. Additionally, for both tasks, depressive symptoms were inversely related to postconflict reaction time adjustments following negative, but not positive, feedback. These findings suggest that subclinical depression is associated with impairments in behavioral adjustments after internal (perceived failure) and external feedback about deficient task performance. (c) 2007 APA, all rights reserved.

When Task Conflict Becomes Personal: The Impact of Perceived Team Performance.

Science.gov (United States)

Guenter, Hannes; van Emmerik, Hetty; Schreurs, Bert; Kuypers, Tom; van Iterson, Ad; Notelaers, Guy

2016-10-01

Although potentially beneficial, task conflict may threaten teams because it often leads to relationship conflict. Prior research has identified a set of interpersonal factors (e.g., team communication, team trust) that help attenuate this association. The purpose of this article is to provide an alternative perspective that focuses on the moderating role of performance-related factors (i.e., perceived team performance). Using social identity theory, we build a model that predicts how task conflict associates with growth in relationship conflict and how perceived team performance influences this association. We test a three-wave longitudinal model by means of random coefficient growth modeling, using data from 60 ongoing teams working in a health care organization. Results provide partial support for our hypotheses. Only when perceived team performance is low, do task conflicts relate with growth in relationship conflict. We conclude that perceived team performance seems to enable teams to uncouple task from relationship conflict.

Group social rank is associated with performance on a spatial learning task.

Science.gov (United States)

Langley, Ellis J G; van Horik, Jayden O; Whiteside, Mark A; Madden, Joah R

2018-02-01

Dominant individuals differ from subordinates in their performances on cognitive tasks across a suite of taxa. Previous studies often only consider dyadic relationships, rather than the more ecologically relevant social hierarchies or networks, hence failing to account for how dyadic relationships may be adjusted within larger social groups. We used a novel statistical method: randomized Elo-ratings, to infer the social hierarchy of 18 male pheasants, Phasianus colchicus , while in a captive, mixed-sex group with a linear hierarchy. We assayed individual learning performance of these males on a binary spatial discrimination task to investigate whether inter-individual variation in performance is associated with group social rank. Task performance improved with increasing trial number and was positively related to social rank, with higher ranking males showing greater levels of success. Motivation to participate in the task was not related to social rank or task performance, thus indicating that these rank-related differences are not a consequence of differences in motivation to complete the task. Our results provide important information about how variation in cognitive performance relates to an individual's social rank within a group. Whether the social environment causes differences in learning performance or instead, inherent differences in learning ability predetermine rank remains to be tested.

Cerebellar tDCS does not affect performance in the N-back task.

Science.gov (United States)

van Wessel, Brenda W V; Claire Verhage, M; Holland, Peter; Frens, Maarten A; van der Geest, Jos N

2016-01-01

The N-back task is widely used in cognitive research. Furthermore, the cerebellum's role in cognitive processes is becoming more widely recognized. Studies using transcranial direct current stimulation (tDCS) have demonstrated effects of cerebellar stimulation on several cognitive tasks. Therefore, the aim of this study was to investigate the effects of cerebellar tDCS on cognitive performance by using the N-back task. The cerebellum of 12 participants was stimulated during the task. Moreover, the cognitive load was manipulated in N = 2, N = 3, and N = 4. Every participant received three tDCS conditions (anodal, cathodal, and sham) divided over three separated days. It was expected that anodal stimulation would improve performance on the task. Each participant performed 6 repetitions of every load in which correct responses, false alarms, and reaction times were recorded. We found significant differences between the three levels of load in the rate of correct responses and false alarms, indicating that subjects followed the expected pattern of performance for the N-back task. However, no significant differences between the three tDCS conditions were found. Therefore, it was concluded that in this study cognitive performance on the N-back task was not readily influenced by cerebellar tDCS, and any true effects are likely to be small. We discuss several limitations in task design and suggest future experiments to address such issues.

A Novel Method for Assessing Task Complexity in Outpatient Clinical-Performance Measures.

Science.gov (United States)

Hysong, Sylvia J; Amspoker, Amber B; Petersen, Laura A

2016-04-01

Clinical-performance measurement has helped improve the quality of health-care; yet success in attaining high levels of quality across multiple domains simultaneously still varies considerably. Although many sources of variability in care quality have been studied, the difficulty required to complete the clinical work itself has received little attention. We present a task-based methodology for evaluating the difficulty of clinical-performance measures (CPMs) by assessing the complexity of their component requisite tasks. Using Functional Job Analysis (FJA), subject-matter experts (SMEs) generated task lists for 17 CPMs; task lists were rated on ten dimensions of complexity, and then aggregated into difficulty composites. Eleven outpatient work SMEs; 133 VA Medical Centers nationwide. Clinical Performance: 17 outpatient CPMs (2000-2008) at 133 VA Medical Centers nationwide. Measure Difficulty: for each CPM, the number of component requisite tasks and the average rating across ten FJA complexity scales for the set of tasks comprising the measure. Measures varied considerably in the number of component tasks (M = 10.56, SD = 6.25, min = 5, max = 25). Measures of chronic care following acute myocardial infarction exhibited significantly higher measure difficulty ratings compared to diabetes or screening measures, but not to immunization measures ([Formula: see text] = 0.45, -0.04, -0.05, and -0.06 respectively; F (3, 186) = 3.57, p = 0.015). Measure difficulty ratings were not significantly correlated with the number of component tasks (r = -0.30, p = 0.23). Evaluating the difficulty of achieving recommended CPM performance levels requires more than simply counting the tasks involved; using FJA to assess the complexity of CPMs' component tasks presents an alternate means of assessing the difficulty of primary-care CPMs and accounting for performance variation among measures and performers. This in turn could be used in designing

The effect of caffeine on cognitive task performance and motor fatigue

NARCIS (Netherlands)

van Duinen, Hiske; Lorist, Monicque M.; Zijdewind, Inge

Rationale: In everyday life, people are usually capable of performing two tasks simultaneously. However, in a previous study we showed that during a fatiguing motor task, cognitive performance declined progressively. There is extensive literature on the ( positive) effects of caffeine on cognitive

Self-Reported Stickiness of Mind-Wandering Affects Task Performance

NARCIS (Netherlands)

van Vugt, Marieke K; Broers, Nico

2016-01-01

When asked to perform a certain task, we typically spend a decent amount of time thinking thoughts unrelated to that task-a phenomenon referred to as "mind-wandering." It is thought that this mind-wandering is driven at least in part by our unfinished goals and concerns. Previous studies have shown

Musical Training, Bilingualism, and Executive Function: A Closer Look at Task Switching and Dual-Task Performance

Science.gov (United States)

Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

2015-01-01

This study investigated whether musical training and bilingualism are associated with enhancements in specific components of executive function, namely, task switching and dual-task performance. Participants (n = 153) belonging to one of four groups (monolingual musician, bilingual musician, bilingual non-musician, or monolingual non-musician)…

The monitoring of radioactive contamination and radiation exposure in the environment in Germany- tasks, techniques, realizations

International Nuclear Information System (INIS)

Bayer, A.

1998-01-01

A brief historical account of the development of the monitoring of radioactivity in the environment in Germany is given. The aims of monitoring and the tasks, classified according to the possible sources of release, are presented and the methods required are described. The monitoring systems, set up on the basis of different legal principles, are presented and the technical realization of these including their current state of development, is described. Finally, an account is given of the coordination of the national monitoring systems which is at present in progress, as well as of the integration of these monitoring systems into international monitoring and information networks. (author)

Task versus relationship conflict, team performance, and team member satisfaction: a meta-analysis.

Science.gov (United States)

De Dreu, Carsten K W; Weingart, Laurie R

2003-08-01

This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, results revealed strong and negative correlations between relationship conflict, team performance, and team member satisfaction. In contrast to what has been suggested in both academic research and introductory textbooks, however, results also revealed strong and negative (instead of the predicted positive) correlations between task conflict team performance, and team member satisfaction. As predicted, conflict had stronger negative relations with team performance in highly complex (decision making, project, mixed) than in less complex (production) tasks. Finally, task conflict was less negatively related to team performance when task conflict and relationship conflict were weakly, rather than strongly, correlated.

Quantitative performance monitoring

International Nuclear Information System (INIS)

Heller, A.S.

1987-01-01

In the recently published update of NUREG/CR 3883, it was shown that Japanese plants of size and design similar to those in the US have significantly fewer trips in a given year of operation. One way to reduce such imbalance is the efficient use of available plant data. Since plant data are recorded and monitored continuously for management feedback and timely resolution of problems, this data should be actively used to increase the efficiency of operations and, ultimately, for a reduction of plant trips in power plants. A great deal of information is lost, however, if the analytical tools available for the data evaluation are misapplied or not adopted at all. This paper deals with a program developed to use quantitative techniques to monitor personnel performance in an operating power plant. Visual comparisons of ongoing performance with predetermined quantitative performance goals are made. A continuous feedback is provided to management for early detection of adverse trends and timely resolution of problems. Ultimately, costs are reduced through effective resource management and timely decision making

Assessing air medical crew real-time readiness to perform critical tasks.

Science.gov (United States)

Braude, Darren; Goldsmith, Timothy; Weiss, Steven J

2011-01-01

Air medical transport has had problems with its safety record, attributed in part to human error. Flight crew members (FCMs) must be able to focus on critical safety tasks in the context of a stressful environment. Flight crew members' cognitive readiness (CR) to perform their jobs may be affected by sleep deprivation, personal problems, high workload, and use of alcohol and drugs. The current study investigated the feasibility of using a computer-based cognitive task to assess FCMs' readiness to perform their job. The FCMs completed a short questionnaire to evaluate their physiologic and psychological state at the beginning and end of each shift. The FCMs then performed 3 minutes of a computer-based cognitive task called synthetic work environment (SYNWIN test battery). Task performance was compared with the questionnaire variables using correlation and regression analysis. Differences between the beginning and end of each shift were matched and compared using a paired Students t test. SYNWIN performance was significantly worse at the end of a shift compared with the beginning of the shift (p = 0.028) primarily because of decrement in the memory component. The SYNWIN composite scores were negatively correlated to degree of irritability felt by the participant, both before (r = -0.25) and after (r = -0.34) a shift and were significantly correlated with amount of sleep (0.22), rest (0.30), and life satisfaction (0.30). Performance by FCMs on a simple, rapid, computer-based psychological test correlates well with self-reported sleep, rest, life satisfaction, and irritability. Although further studies are warranted, these findings suggest that assessment of the performance of FCMs on a simple, rapid, computer-based, multitasking battery is feasible as an approach to determine their readiness to perform critical safety tasks through the SYNWIN task battery.

Self-reported quality of ADL task performance among patients with COPD exacerbations

DEFF Research Database (Denmark)

Bendixen, Hans Jørgen; Wæhrens, Eva Elisabet Ejlersen; Wilcke, Jon Torgny

2014-01-01

OBJECTIVE: Patients suffering from chronic obstructive pulmonary disease (COPD) experience problems in the performance of activities of daily living (ADL) tasks. The objective was to examine the self-reported quality of ADL task performance among COPD patients, and to investigate whether age...... concerning age, gender, and routine COPD characteristics were drawn from the patients' medical records. RESULTS: The patients reported being inefficient to markedly inefficient when performing ADL tasks within the personal hygiene, toileting, dressing, household, mobility, and transportation domains. While...... more than 90% of the participants reported increased effort and/or fatigue when performing the ADL tasks, up to 88% of the participants relied on help from others in the performance of general household chores like cooking and shopping. Self-reported ADL ability did not correlate with age, gender...

Differential effects of emotionally versus neutrally cued autobiographical memories on performance of a subsequent cognitive task: Effects of task difficulty

Directory of Open Access Journals (Sweden)

Kymberly eYoung

2012-08-01

Full Text Available Attention is a limited resource, and in order to improve processing of the attended information, competing processes must be suppressed. Although it is well established that an experimentally induced change in mood state comprises one type of competing process that can impair performance on a subsequent task, no study has investigated whether an emotionally valenced autobiographical memory (AM also can alter performance on a subsequent task. We therefore examined the effects of AM recall on cognitive performance. Healthy participants (n=20 per experiment recalled AMs in response to positive, negative, and neutral cue words. Following each AM participants completed a simple perceptual task (Experiment 1 or solved moderately difficult subtraction problems (Experiment 2. In Experiment 1 participants performed less accurately following exposure to positive or negative versus neutral cue words (ps<0.001, and also were less accurate following negative versus positive cue words (p<0.001. In Experiment 2, in contrast, no difference in accuracy or response times reached statistical significance. Performance accuracy even trended towards being higher following exposure to negative versus neutral cue words (p=0.08. The results of Experiment 1 suggested that recalling emotionally salient AMs reduces the attention directed toward a simple continuous performance task administered immediately following the AM task, conceivably due to persistent contemplation of the AM. The negative results of Experiment 2 suggested that the effect of AMs on attention was attenuated, however, by increasing the difficulty of the subsequent task. Our results have implications for patients with MDD, as performing cognitively demanding tasks may allow them to attenuate the impairing effects of negative rumination on cognition.

Neuronal Substrates Underlying Performance Variability in Well-Trained Skillful Motor Task in Humans.

Science.gov (United States)

Mizuguchi, Nobuaki; Uehara, Shintaro; Hirose, Satoshi; Yamamoto, Shinji; Naito, Eiichi

2016-01-01

Motor performance fluctuates trial by trial even in a well-trained motor skill. Here we show neural substrates underlying such behavioral fluctuation in humans. We first scanned brain activity with functional magnetic resonance imaging while healthy participants repeatedly performed a 10 s skillful sequential finger-tapping task. Before starting the experiment, the participants had completed intensive training. We evaluated task performance per trial (number of correct sequences in 10 s) and depicted brain regions where the activity changes in association with the fluctuation of the task performance across trials. We found that the activity in a broader range of frontoparietocerebellar network, including the bilateral dorsolateral prefrontal cortex (DLPFC), anterior cingulate and anterior insular cortices, and left cerebellar hemisphere, was negatively correlated with the task performance. We further showed in another transcranial direct current stimulation (tDCS) experiment that task performance deteriorated, when we applied anodal tDCS to the right DLPFC. These results indicate that fluctuation of brain activity in the nonmotor frontoparietocerebellar network may underlie trial-by-trial performance variability even in a well-trained motor skill, and its neuromodulation with tDCS may affect the task performance.

Relationships between Contextual and Task Performance and Interrater Agreement: Are There Any?

Science.gov (United States)

Díaz-Vilela, Luis F; Delgado Rodríguez, Naira; Isla-Díaz, Rosa; Díaz-Cabrera, Dolores; Hernández-Fernaud, Estefanía; Rosales-Sánchez, Christian

2015-01-01

Work performance is one of the most important dependent variables in Work and Organizational Psychology. The main objective of this paper was to explore the relationships between citizenship performance and task performance measures obtained from different appraisers and their consistency through a seldom-used methodology, intraclass correlation coefficients. Participants were 135 public employees, the total staff in a local government department. Jobs were clustered into job families through a work analysis based on standard questionnaires. A task description technique was used to develop a performance appraisal questionnaire for each job family, with three versions: self-, supervisor-, and peer-evaluation, in addition to a measure of citizenship performance. Only when the self-appraisal bias is controlled, significant correlations appeared between task performance rates. However, intraclass correlations analyses show that only self- (contextual and task) performance measures are consistent, while interrater agreement disappears. These results provide some interesting clues about the procedure of appraisal instrument development, the role of appraisers, and the importance of choosing adequate consistency analysis methods.

The Effects of Background Music on Primary School Pupils' Task Performance.

Science.gov (United States)

Hallam, Susan; Price, John; Katsarou, Georgia

2002-01-01

Presents two studies that explored the effects of music perceived as calming and relaxing on arithmetic and memory performance tasks of 10- to 12-year-old children. Reports that the calming music led to better performance on both tasks when compared with the non-music condition. Includes references. (CMK)

Concurrent performance of two memory tasks: evidence for domain-specific working memory systems.

Science.gov (United States)

Cocchini, Gianna; Logie, Robert H; Della Sala, Sergio; MacPherson, Sarah E; Baddeley, Alan D

2002-10-01

Previous studies of dual-task coordination in working memory have shown a lack of dual-task interference when a verbal memory task is combined with concurrent perceptuomotor tracking. Two experiments are reported in which participants were required to perform pairwise combinations of (1) a verbal memory task, a visual memory task, and perceptuomotor tracking (Experiment 1), and (2) pairwise combinations of the two memory tasks and articulatory suppression (Experiment 2). Tracking resulted in no disruption of the verbal memory preload over and above the impact of a delay in recall and showed only minimal disruption of the retention of the visual memory load. Performing an ongoing verbal memory task had virtually no impact on retention of a visual memory preload or vice versa, indicating that performing two demanding memory tasks results in little mutual interference. Experiment 2 also showed minimal disruption when the two memory tasks were combined, although verbal memory (but not visual memory) was clearly disrupted by articulatory suppression interpolated between presentation and recall. These data suggest that a multiple-component working memory model provides a better account for performance in concurrent immediate memory tasks than do theories that assume a single processing and storage system or a limited-capacity attentional system coupled with activated memory traces.

Blue or red? Exploring the effect of color on cognitive task performances.

Science.gov (United States)

Mehta, Ravi; Zhu, Rui Juliet

2009-02-27

Existing research reports inconsistent findings with regard to the effect of color on cognitive task performances. Some research suggests that blue or green leads to better performances than red; other studies record the opposite. Current work reconciles this discrepancy. We demonstrate that red (versus blue) color induces primarily an avoidance (versus approach) motivation (study 1, n = 69) and that red enhances performance on a detail-oriented task, whereas blue enhances performance on a creative task (studies 2 and 3, n = 208 and 118). Further, we replicate these results in the domains of product design (study 4, n = 42) and persuasive message evaluation (study 5, n = 161) and show that these effects occur outside of individuals' consciousness (study 6, n = 68). We also provide process evidence suggesting that the activation of alternative motivations mediates the effect of color on cognitive task performances.

Using task performance to inform treatment planning for youth with ADHD: A systematic review.

Science.gov (United States)

Molitor, Stephen J; Langberg, Joshua M

2017-12-01

The role that neuropsychological task performance plays in the assessment of Attention-Deficit/Hyperactivity Disorder (ADHD) is currently ambiguous, and findings are mixed regarding whether tasks have validity for diagnosing the disorder. Irrespective of their validity for diagnosing ADHD, neuropsychological tasks could provide valuable information to mental health professionals if they can inform recommendations for treatment targets and modalities. Therefore, this review sought to synthesize the available evidence related to the use of neuropsychological task performance as a tool for informing treatment planning for youth with ADHD. Reviewed studies focused on examinations of associations between task performance and academic, social, and health outcomes, as well as response to treatment. Twenty-five relevant studies using samples of youth diagnosed with ADHD in clinical, community, and school settings were identified. Review of the evidence suggests that task performance may be useful in identifying individuals with ADHD at risk for academic impairment. However, the evidence is less compelling for identifying youth at risk for impaired social functioning or poor health outcomes. The review also found that task performance is likely useful for predicting response to treatment with methylphenidate. Across studies, evidence indicated that interpreting task performance in an integrated manner, such as a factor score or mean score, was more consistently useful for predicting outcomes of interest than interpreting performance from a single task. Implications for the use of tasks in ADHD assessments are discussed, and future directions are outlined for further examining the clinical utility of task performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reduced Dual-Task Performance in MS Patients Is Further Decreased by Muscle Fatigue.

Science.gov (United States)

Wolkorte, Ria; Heersema, Dorothea J; Zijdewind, Inge

2015-06-01

Multiple sclerosis (MS) can be accompanied by motor, cognitive, and sensory impairments. Additionally, MS patients often report fatigue as one of their most debilitating symptoms. It is, therefore, expected that MS patients will have difficulties in performing cognitive-motor dual tasks (DTs), especially in a fatiguing condition. To determine whether MS patients are more challenged by a DT than controls in a fatiguing and less-fatiguing condition and whether DT performance is associated with perceived fatigue. A group of 19 MS patients and 19 age-, sex-, and education-matched controls performed a cognitive task (2-choice reaction time task) separately or concurrent with a low-force or a high-force motor task (index finger abduction at 10% or 30% maximal voluntary contraction). MS patients performed less well on a cognitive task than controls. Cognitive task performance under DT conditions decreased more for MS patients. Moreover, under high-force DT conditions, cognitive performance declined in both groups but to a larger degree for MS patients. Besides a decline in cognitive task performance, MS patients also showed a stronger decrease in motor performance under high-force DT conditions. DT costs were positively related to perceived fatigue as measured by questionnaires. Compared with controls, MS patients performed less well on DTs as demonstrated by a reduction in both cognitive and motor performances. This performance decrease was stronger under fatiguing conditions and was related to the sense of fatigue of MS patients. These data illustrate problems that MS patients may encounter in daily life because of their fatigue. © The Author(s) 2014.

Ranking Performance Measures in Multi-Task Agencies

DEFF Research Database (Denmark)

Christensen, Peter Ove; Sabac, Florin; Tian, Joyce

We derive sufficient conditions for ranking performance evaluation systems in multi-task agency models using both optimal and linear contracts in terms of a second-order stochastic dominance (SSD) condition on the likelihood ratios. The SSD condition can be replaced by a variance-covariance matrix...

Application of monitoring, diagnosis, and prognosis in thermal performance analysis for nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyeong Min; Heo, Gyun Young [Kyung Hee University, Yongin (Korea, Republic of); Na, Man Gyun [Chosun University, Gwangju (Korea, Republic of)

2014-12-15

As condition-based maintenance (CBM) has risen as a new trend, there has been an active movement to apply information technology for effective implementation of CBM in power plants. This motivation is widespread in operations and maintenance, including monitoring, diagnosis, prognosis, and decision-making on asset management. Thermal efficiency analysis in nuclear power plants (NPPs) is a longstanding concern being updated with new methodologies in an advanced IT environment. It is also a prominent way to differentiate competitiveness in terms of operations and maintenance costs. Although thermal performance tests implemented using industrial codes and standards can provide officially trustworthy results, they are essentially resource-consuming and maybe even a hind-sighted technique rather than a foresighted one, considering their periodicity. Therefore, if more accurate performance monitoring can be achieved using advanced data analysis techniques, we can expect more optimized operations and maintenance. This paper proposes a framework and describes associated methodologies for in-situ thermal performance analysis, which differs from conventional performance monitoring. The methodologies are effective for monitoring, diagnosis, and prognosis in pursuit of CBM. Our enabling techniques cover the intelligent removal of random and systematic errors, deviation detection between a best condition and a currently measured condition, degradation diagnosis using a structured knowledge base, and prognosis for decision-making about maintenance tasks. We also discuss how our new methods can be incorporated with existing performance tests. We provide guidance and directions for developers and end-users interested in in-situ thermal performance management, particularly in NPPs with large steam turbines.

Application of monitoring, diagnosis, and prognosis in thermal performance analysis for nuclear power plants

International Nuclear Information System (INIS)

Kim, Hyeong Min; Heo, Gyun Young; Na, Man Gyun

2014-01-01

As condition-based maintenance (CBM) has risen as a new trend, there has been an active movement to apply information technology for effective implementation of CBM in power plants. This motivation is widespread in operations and maintenance, including monitoring, diagnosis, prognosis, and decision-making on asset management. Thermal efficiency analysis in nuclear power plants (NPPs) is a longstanding concern being updated with new methodologies in an advanced IT environment. It is also a prominent way to differentiate competitiveness in terms of operations and maintenance costs. Although thermal performance tests implemented using industrial codes and standards can provide officially trustworthy results, they are essentially resource-consuming and maybe even a hind-sighted technique rather than a foresighted one, considering their periodicity. Therefore, if more accurate performance monitoring can be achieved using advanced data analysis techniques, we can expect more optimized operations and maintenance. This paper proposes a framework and describes associated methodologies for in-situ thermal performance analysis, which differs from conventional performance monitoring. The methodologies are effective for monitoring, diagnosis, and prognosis in pursuit of CBM. Our enabling techniques cover the intelligent removal of random and systematic errors, deviation detection between a best condition and a currently measured condition, degradation diagnosis using a structured knowledge base, and prognosis for decision-making about maintenance tasks. We also discuss how our new methods can be incorporated with existing performance tests. We provide guidance and directions for developers and end-users interested in in-situ thermal performance management, particularly in NPPs with large steam turbines.

Exploration of task performance tests in a physics laboratory

Science.gov (United States)

Liu, Dan; El Turkey, Houssein

2017-11-01

In this article, we investigate the implementation of task performance tests in an undergraduate physics laboratory. Two performance tests were carried out over two semesters using the task of building a DC circuit. The first implementation in Spring 2014 had certain concerns such as the privacy of students’ testing and their ‘trial and error’ attempts. These concerns were addressed in Fall 2015 through implementing a second performance test. The second implementation was administered differently but the content of the two tests was the same. We discuss the validity of both implementations and present the correlation (or lack of) between the time that students needed to complete the tests and their grades from a paper-based laboratory assessment method.

Does Degree of Work Task Completion Influence Retrieval Performance?

DEFF Research Database (Denmark)

Ingwersen, Peter; Bogers, Toine; Lykke, Marianne

2010-01-01

their perception of task completion. Also, with the exception of full text records and across all document types, both measured at rank 10, no statistically significant correlation is observed with respect to retrieval performance influenced by degrees of perceived work task completion or individual types......In this contribution we investigate the potential influence between assessors’ perceived completion of their work task at hand and their actual assessment of usefulness of the retrieved information. The results indicate that the number of useful documents found by assessors does not influence...

Task-specific monitoring of nuclear medicine technologists' radiation exposure

International Nuclear Information System (INIS)

Smart, R.

2004-01-01

Many studies have demonstrated that the exposure of nuclear medicine technologists arises primarily from radioactive patients rather than from preparation of radiopharmaceuticals. However, in order to devise strategies to reduce staff exposure, it is necessary to identify the specific tasks within each procedure that result in the highest radiation doses. An ESM Eberline FH41B-10 radiation dosemeter, which records the ambient dose equivalent rate, was used to monitor the radiation exposure of a technologist and to record the dose rate in μSv per hour every 32 s throughout a working day. The technologist recorded the procedures that were being performed so that the procedures that resulted in higher doses could be identified clearly. The measured doses clearly showed that the major contributions to the technologist's dose were the following: (1) transferring incapacitated patients from the imaging table to a hospital trolley; (2) difficult injections without syringe shields; and (3) setting up patients for gated myocardial scans. The average dose to the technologist from transferring patients after a bone scan was 0.54 μSv, 40% of the total dose of 1.3 μSv for the complete bone scan procedure. The average dose received injecting 900 MBq of 99 Tc m -HDP using a tungsten syringe shield was 0.57 μSv, but the highest dose was 1.6 μSv, in a patient in whom the injection was difficult. A 0.5 mm lead apron was found to reduce the dose when setting up a patient for a gated stress 99 Tc m -sestamibi myocardial scan by approximately a factor of 2. The average dose per patient for this task was reduced from 1.1 to 0.6 μSv. It is recommended that staff waiting for assistance with patient transfers stand away from the patient, that tungsten syringe shields be used for all radiopharmaceutical injections and that a 0.5 mm lead apron be worn when attending patients containing high activities of 99 Tc m radiopharmaceuticals, such as those having myocardial imaging. (authors)

Shared performance monitor in a multiprocessor system

Science.gov (United States)

Chiu, George; Gara, Alan G.; Salapura, Valentina

2012-07-24

A performance monitoring unit (PMU) and method for monitoring performance of events occurring in a multiprocessor system. The multiprocessor system comprises a plurality of processor devices units, each processor device for generating signals representing occurrences of events in the processor device, and, a single shared counter resource for performance monitoring. The performance monitor unit is shared by all processor cores in the multiprocessor system. The PMU comprises: a plurality of performance counters each for counting signals representing occurrences of events from one or more the plurality of processor units in the multiprocessor system; and, a plurality of input devices for receiving the event signals from one or more processor devices of the plurality of processor units, the plurality of input devices programmable to select event signals for receipt by one or more of the plurality of performance counters for counting, wherein the PMU is shared between multiple processing units, or within a group of processors in the multiprocessing system. The PMU is further programmed to monitor event signals issued from non-processor devices.

Game-based training of flexibility and attention improves task-switch performance: near and far transfer of cognitive training in an EEG study.

Science.gov (United States)

Olfers, Kerwin J F; Band, Guido P H

2018-01-01

There is a demand for ways to enhance cognitive flexibility, as it can be a limiting factor for performance in daily life. Video game training has been linked to advantages in cognitive functioning, raising the question if training with video games can promote cognitive flexibility. In the current study, we investigated if game-based computerized cognitive training (GCCT) could enhance cognitive flexibility in a healthy young adult sample (N = 72), as measured by task-switch performance. Three GCCT schedules were contrasted, which targeted: (1) cognitive flexibility and task switching, (2) attention and working memory, or (3) an active control involving basic math games, in twenty 45-min sessions across 4-6 weeks. Performance on an alternating-runs task-switch paradigm during pretest and posttest sessions indicated greater overall reaction time improvements after both flexibility and attention training as compared to control, although not related to local switch cost. Flexibility training enhanced performance in the presence of distractor-related interference. In contrast, attention training was beneficial when low task difficulty undermined sustained selective attention. Furthermore, flexibility training improved response selection as indicated by a larger N2 amplitude after training as compared to control, and more efficient conflict monitoring as indicated by reduced Nc/CRN and larger Pe amplitude after training. These results provide tentative support for the efficacy of GCCT and suggest that an ideal training might include both task switching and attention components, with maximal task diversity both within and between training games.

Performance management in healthcare : performance indicator development, task uncertainty, and types of performance indicators

NARCIS (Netherlands)

Geer-Rutten-Rijswijk, van der E.; Tuijl, van H.F.J.M.; Rutte, C.G.

2009-01-01

In healthcare, performance indicators are increasingly used to measure and control quality and efficiency of care-providing teams. This article demonstrates that when controllability is emphasized during indicator development, the level of task uncertainty influences the type of resulting

Occupational-Specific Strength Predicts Astronaut-Related Task Performance in a Weighted Suit.

Science.gov (United States)

Taylor, Andrew; Kotarsky, Christopher J; Bond, Colin W; Hackney, Kyle J

2018-01-01

Future space missions beyond low Earth orbit will require deconditioned astronauts to perform occupationally relevant tasks within a planetary spacesuit. The prediction of time-to-completion (TTC) of astronaut tasks will be critical for crew safety, autonomous operations, and mission success. This exploratory study determined if the addition of task-specific strength testing to current standard lower body testing would enhance the prediction of TTC in a 1-G test battery. Eight healthy participants completed NASA lower body strength tests, occupationally specific strength tests, and performed six task simulations (hand drilling, construction wrenching, incline walking, collecting weighted samples, and dragging an unresponsive crewmember to safety) in a 48-kg weighted suit. The TTC for each task was recorded and summed to obtain a total TTC for the test battery. Linear regression was used to predict total TTC with two models: 1) NASA lower body strength tests; and 2) NASA lower body strength tests + occupationally specific strength tests. Total TTC of the test battery ranged from 20.2-44.5 min. The lower body strength test alone accounted for 61% of the variability in total TTC. The addition of hand drilling and wrenching strength tests accounted for 99% of the variability in total TTC. Adding occupationally specific strength tests (hand drilling and wrenching) to standard lower body strength tests successfully predicted total TTC in a performance test battery within a weighted suit. Future research should couple these strength tests with higher fidelity task simulations to determine the utility and efficacy of task performance prediction.Taylor A, Kotarsky CJ, Bond CW, Hackney KJ. Occupational-specific strength predicts astronaut-related task performance in a weighted suit. Aerosp Med Hum Perform. 2018; 89(1):58-62.

Individualized tracking of self-directed motor learning in group-housed mice performing a skilled lever positioning task in the home cage.

Science.gov (United States)

Silasi, Gergely; Boyd, Jamie D; Bolanos, Federico; LeDue, Jeff M; Scott, Stephen H; Murphy, Timothy H

2018-01-01

Skilled forelimb function in mice is traditionally studied through behavioral paradigms that require extensive training by investigators and are limited by the number of trials individual animals are able to perform within a supervised session. We developed a skilled lever positioning task that mice can perform within their home cage. The task requires mice to use their forelimb to precisely hold a lever mounted on a rotary encoder within a rewarded position to dispense a water reward. A Raspberry Pi microcomputer is used to record lever position during trials and to control task parameters, thus making this low-footprint apparatus ideal for use within animal housing facilities. Custom Python software automatically increments task difficulty by requiring a longer hold duration, or a more accurate hold position, to dispense a reward. The performance of individual animals within group-housed mice is tracked through radio-frequency identification implants, and data stored on the microcomputer may be accessed remotely through an active internet connection. Mice continuously engage in the task for over 2.5 mo and perform ~500 trials/24 h. Mice required ~15,000 trials to learn to hold the lever within a 10° range for 1.5 s and were able to further refine movement accuracy by limiting their error to a 5° range within each trial. These results demonstrate the feasibility of autonomously training group-housed mice on a forelimb motor task. This paradigm may be used in the future to assess functional recovery after injury or cortical reorganization induced by self-directed motor learning. NEW & NOTEWORTHY We developed a low-cost system for fully autonomous training of group-housed mice on a forelimb motor task. We demonstrate the feasibility of tracking both end-point, as well as kinematic performance of individual mice, with each performing thousands of trials over 2.5 mo. The task is run and controlled by a Raspberry Pi microcomputer, which allows for cages to be

78 FR 15112 - Rulemaking Advisory Committee; Transport Airplane Performance and Handling Characteristics-New Task

Science.gov (United States)

2013-03-08

... Committee; Transport Airplane Performance and Handling Characteristics--New Task AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of new task assignment for the Aviation Rulemaking Advisory Committee... findings. The Task The FAA tasked ARAC to consider several areas within the airplane performance and...

Real-time performance monitoring and management system

Science.gov (United States)

Budhraja, Vikram S [Los Angeles, CA; Dyer, James D [La Mirada, CA; Martinez Morales, Carlos A [Upland, CA

2007-06-19

A real-time performance monitoring system for monitoring an electric power grid. The electric power grid has a plurality of grid portions, each grid portion corresponding to one of a plurality of control areas. The real-time performance monitoring system includes a monitor computer for monitoring at least one of reliability metrics, generation metrics, transmission metrics, suppliers metrics, grid infrastructure security metrics, and markets metrics for the electric power grid. The data for metrics being monitored by the monitor computer are stored in a data base, and a visualization of the metrics is displayed on at least one display computer having a monitor. The at least one display computer in one said control area enables an operator to monitor the grid portion corresponding to a different said control area.

Effect of music tempo on task performance.

Science.gov (United States)

Mayfield, C; Moss, S

1989-12-01

Two studies were conducted to evaluate the effect of music tempo on task performance. In Study 1, 44 undergraduate business students were asked to be "workers" in a stock market project by collecting closing stock prices and calculating the percentage of change in the price from week to week. Subjects were randomly divided into groups such that they either listened to fast-paced music while they worked, to slow-paced music, or to no music. Analyses of variance and covariance were conducted on both the quantity and quality of the subjects' work, using music listening habits as a covariate. There were no differences in either the quantity or quality of the work produced by the groups. There were some methodological concerns regarding Study 1, so a second study was conducted. The 70 undergraduate business students in Study 2 completed the same task under the same music conditions as in Study 1. Analyses of variance indicated women performed significantly better than men, performance was significantly higher in the rock condition than in the heartbeat condition, and subjects in the rock condition had a significantly higher perceived level of distraction by the music.

Relationships between Contextual and Task Performance and Interrater Agreement: Are There Any?

Directory of Open Access Journals (Sweden)

Luis F Díaz-Vilela

Full Text Available Work performance is one of the most important dependent variables in Work and Organizational Psychology. The main objective of this paper was to explore the relationships between citizenship performance and task performance measures obtained from different appraisers and their consistency through a seldom-used methodology, intraclass correlation coefficients. Participants were 135 public employees, the total staff in a local government department. Jobs were clustered into job families through a work analysis based on standard questionnaires. A task description technique was used to develop a performance appraisal questionnaire for each job family, with three versions: self-, supervisor-, and peer-evaluation, in addition to a measure of citizenship performance. Only when the self-appraisal bias is controlled, significant correlations appeared between task performance rates. However, intraclass correlations analyses show that only self- (contextual and task performance measures are consistent, while interrater agreement disappears. These results provide some interesting clues about the procedure of appraisal instrument development, the role of appraisers, and the importance of choosing adequate consistency analysis methods.

Social Anxiety, Affect, Cortisol Response and Performance on a Speech Task.

Science.gov (United States)

Losiak, Wladyslaw; Blaut, Agata; Klosowska, Joanna; Slowik, Natalia

2016-01-01

Social anxiety is characterized by increased emotional reactivity to social stimuli, but results of studies focusing on affective reactions of socially anxious subjects in the situation of social exposition are inconclusive, especially in the case of endocrinological measures of affect. This study was designed to examine individual differences in endocrinological and affective reactions to social exposure as well as in performance on a speech task in a group of students (n = 44) comprising subjects with either high or low levels of social anxiety. Measures of salivary cortisol and positive and negative affect were taken before and after an impromptu speech. Self-ratings and observer ratings of performance were also obtained. Cortisol levels and negative affect increased in both groups after the speech task, and positive affect decreased; however, group × affect interactions were not significant. Assessments conducted after the speech task revealed that highly socially anxious participants had lower observer ratings of performance while cortisol increase and changes in self-reported affect were not related to performance. Socially anxious individuals do not differ from nonanxious individuals in affective reactions to social exposition, but reveal worse performance at a speech task. © 2015 S. Karger AG, Basel.

Frontal subregions mediating Elevator Counting task performance.

Science.gov (United States)

MacPherson, Sarah E; Turner, Martha S; Bozzali, Marco; Cipolotti, Lisa; Shallice, Tim

2010-10-01

Deficits in sustained attention may lead to action slips in everyday life as irrelevant action sequences are inappropriately triggered internally or by the environment. While deficits in sustained attention have been associated with damage to the frontal lobes of the brain, little is known about the role of the frontal lobes in the Elevator Counting subtest of the Test of Everyday Attention. In the current study, 55 frontal patients subdivided into medial, orbital and lateral subgroups, 18 patients with posterior lesions and 82 healthy controls performed the Elevator Counting task. The results revealed that patients with medial and left lateral prefrontal lesions were significantly impaired on the task compared to healthy controls. Research suggests that patients with medial lesions are susceptible to competition from task irrelevant schema; whereas the left lateral group in the current study may fail to keep track of the tones already presented. Copyright © 2010 Elsevier Ltd. All rights reserved.

The effect of video game "warm-up" on performance of laparoscopic surgery tasks.

Science.gov (United States)

Rosser, James C; Gentile, Douglas A; Hanigan, Kevin; Danner, Omar K

2012-01-01

Performing laparoscopic procedures requires special training and has been documented as a significant source of surgical errors. "Warming up" before performing a task has been shown to enhance performance. This study investigates whether surgeons benefit from "warming up" using select video games immediately before performing laparoscopic partial tasks and clinical tasks. This study included 303 surgeons (249 men and 54 women). Participants were split into a control (n=180) and an experimental group (n=123). The experimental group played 3 previously validated video games for 6 minutes before task sessions. The Cobra Rope partial task and suturing exercises were performed immediately after the warm-up sessions. Surgeons who played video games prior to the Cobra Rope drill were significantly faster on their first attempt and across all 10 trials. The experimental and control groups were significantly different in their total suturing scores (t=2.28, df=288, Pvideo games prior to performing laparoscopic partial and clinical tasks (intracorporeal suturing) were faster and had fewer errors than participants not engaging in "warm-up." More study is needed to determine whether this translates into superior procedural execution in the clinical setting.

Influence of visual feedback on human task performance in ITER remote handling

Energy Technology Data Exchange (ETDEWEB)

Schropp, Gwendolijn Y.R., E-mail: g.schropp@heemskerk-innovative.nl [Utrecht University, Utrecht (Netherlands); Heemskerk Innovative Technology, Noordwijk (Netherlands); Heemskerk, Cock J.M. [Heemskerk Innovative Technology, Noordwijk (Netherlands); Kappers, Astrid M.L.; Tiest, Wouter M. Bergmann [Helmholtz Institute-Utrecht University, Utrecht (Netherlands); Elzendoorn, Ben S.Q. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM/FOM, Partner in the Trilateral Euregio Clusterand ITER-NL, PO box 1207, 3430 BE Nieuwegein (Netherlands); Bult, David [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM/FOM, Partner in the Trilateral Euregio Clusterand ITER-NL, PO box 1207, 3430 BE Nieuwegein (Netherlands)

2012-08-15

Highlights: Black-Right-Pointing-Pointer The performance of human operators in an ITER-like test facility for remote handling. Black-Right-Pointing-Pointer Different sources of visual feedback influence how fast one can complete a maintenance task. Black-Right-Pointing-Pointer Insights learned could be used in design of operator work environment or training procedures. - Abstract: In ITER, maintenance operations will be largely performed by remote handling (RH). Before ITER can be put into operation, safety regulations and licensing authorities require proof of maintainability for critical components. Part of the proof will come from using standard components and procedures. Additional verification and validation is based on simulation and hardware tests in 1:1 scale mockups. The Master Slave manipulator system (MS2) Benchmark Product was designed to implement a reference set of maintenance tasks representative for ITER remote handling. Experiments were performed with two versions of the Benchmark Product. In both experiments, the quality of visual feedback varied by exchanging direct view with indirect view (using video cameras) in order to measure and analyze its impact on human task performance. The first experiment showed that both experienced and novice RH operators perform a simple task significantly better with direct visual feedback than with camera feedback. A more complex task showed a large variation in results and could not be completed by many novice operators. Experienced operators commented on both the mechanical design and visual feedback. In a second experiment, a more elaborate task was tested on an improved Benchmark product. Again, the task was performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indicated that they regarded the lack of 3D perception as the primary factor hindering their performance.

Influence of visual feedback on human task performance in ITER remote handling

International Nuclear Information System (INIS)

Schropp, Gwendolijn Y.R.; Heemskerk, Cock J.M.; Kappers, Astrid M.L.; Tiest, Wouter M. Bergmann; Elzendoorn, Ben S.Q.; Bult, David

2012-01-01

Highlights: ► The performance of human operators in an ITER-like test facility for remote handling. ► Different sources of visual feedback influence how fast one can complete a maintenance task. ► Insights learned could be used in design of operator work environment or training procedures. - Abstract: In ITER, maintenance operations will be largely performed by remote handling (RH). Before ITER can be put into operation, safety regulations and licensing authorities require proof of maintainability for critical components. Part of the proof will come from using standard components and procedures. Additional verification and validation is based on simulation and hardware tests in 1:1 scale mockups. The Master Slave manipulator system (MS2) Benchmark Product was designed to implement a reference set of maintenance tasks representative for ITER remote handling. Experiments were performed with two versions of the Benchmark Product. In both experiments, the quality of visual feedback varied by exchanging direct view with indirect view (using video cameras) in order to measure and analyze its impact on human task performance. The first experiment showed that both experienced and novice RH operators perform a simple task significantly better with direct visual feedback than with camera feedback. A more complex task showed a large variation in results and could not be completed by many novice operators. Experienced operators commented on both the mechanical design and visual feedback. In a second experiment, a more elaborate task was tested on an improved Benchmark product. Again, the task was performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indicated that they regarded the lack of 3D perception as the primary factor hindering their performance.

Implicit Motives, Explicit Traits, and Task and Contextual Performance at Work

DEFF Research Database (Denmark)

Lang, J.W.B.; Zettler, Ingo; Ewen, C.

2012-01-01

for implicit achievement). As a test of these theoretical ideas, we report a study in which employees (N = 241) filled out a questionnaire booklet and worked on an improved modern implicit motive measure, the operant motive test. Their supervisors rated their task and contextual performance. Results support 4...... apply these ideas in the context of industrial and organizational psychology and propose that 2 explicit traits work as channels for the expression of 3 core implicit motives in task and contextual job performance (extraversion for implicit affiliation and implicit power; explicit achievement...... of the 6 theoretical predictions and show that interactions between implicit motives and explicit traits increase the explained criterion variance in both task and contextual performance....

Investigating conversational dynamics: Interactive alignment, Interpersonal synergy, and collective task performance

DEFF Research Database (Denmark)

Fusaroli, Riccardo; Tylén, Kristian

2016-01-01

This study investigates interpersonal processes underlying dialog by comparing two approaches, interactive alignment and interpersonal synergy, and assesses how they predict collective performance in a joint task. While the interactive alignment approach highlights imitative patterns between...... and their impact on collective performance in a corpus of task-oriented conversations. The results show statistical presence of patterns relevant for both approaches. However, synergetic aspects of dialog provide the best statistical predictors of collective performance and adding aspects of the alignment approach...... does not improve the model. This suggests that structural organization at the level of the interaction plays a crucial role in task-oriented conversations, possibly constraining and integrating processes related to alignment....

Impact of monetary incentives on cognitive performance and error monitoring following sleep deprivation.

Science.gov (United States)

Hsieh, Shulan; Li, Tzu-Hsien; Tsai, Ling-Ling

2010-04-01

To examine whether monetary incentives attenuate the negative effects of sleep deprivation on cognitive performance in a flanker task that requires higher-level cognitive-control processes, including error monitoring. Twenty-four healthy adults aged 18 to 23 years were randomly divided into 2 subject groups: one received and the other did not receive monetary incentives for performance accuracy. Both subject groups performed a flanker task and underwent electroencephalographic recordings for event-related brain potentials after normal sleep and after 1 night of total sleep deprivation in a within-subject, counterbalanced, repeated-measures study design. Monetary incentives significantly enhanced the response accuracy and reaction time variability under both normal sleep and sleep-deprived conditions, and they reduced the effects of sleep deprivation on the subjective effort level, the amplitude of the error-related negativity (an error-related event-related potential component), and the latency of the P300 (an event-related potential variable related to attention processes). However, monetary incentives could not attenuate the effects of sleep deprivation on any measures of behavior performance, such as the response accuracy, reaction time variability, or posterror accuracy adjustments; nor could they reduce the effects of sleep deprivation on the amplitude of the Pe, another error-related event-related potential component. This study shows that motivation incentives selectively reduce the effects of total sleep deprivation on some brain activities, but they cannot attenuate the effects of sleep deprivation on performance decrements in tasks that require high-level cognitive-control processes. Thus, monetary incentives and sleep deprivation may act through both common and different mechanisms to affect cognitive performance.

Evidence that communication impairment in schizophrenia is associated with generalized poor task performance.

Science.gov (United States)

Merrill, Anne M; Karcher, Nicole R; Cicero, David C; Becker, Theresa M; Docherty, Anna R; Kerns, John G

2017-03-01

People with schizophrenia exhibit wide-ranging cognitive deficits, including slower processing speed and decreased cognitive control. Disorganized speech symptoms, such as communication impairment, have been associated with poor cognitive control task performance (e.g., goal maintenance and working memory). Whether communication impairment is associated with poorer performance on a broader range of non-cognitive control measures is unclear. In the current study, people with schizophrenia (n =51) and non-psychiatric controls (n =26) completed speech interviews allowing for reliable quantitative assessment of communication impairment. Participants also completed multiple goal maintenance and working memory tasks. In addition, we also examined (a) simple measures of processing speed involving highly automatic prepotent responses and (b) a non-cognitive control measure of general task performance. Schizophrenia communication impairment was significantly associated with poor performance in all cognitive domains, with the largest association found with processing speed (r s =-0.52). Further, communication impairment was also associated with the non-cognitive control measure of poor general task performance (r s =-0.43). In contrast, alogia, a negative speech symptom, and positive symptoms were less if at all related to cognitive task performance. Overall, this study suggests that communication impairment in schizophrenia may be associated with relatively generalized poor cognitive task performance. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Does complexity matter? Meta-analysis of learner performance in artificial grammar tasks.

Science.gov (United States)

Schiff, Rachel; Katan, Pesia

2014-01-01

Complexity has been shown to affect performance on artificial grammar learning (AGL) tasks (categorization of test items as grammatical/ungrammatical according to the implicitly trained grammar rules). However, previously published AGL experiments did not utilize consistent measures to investigate the comprehensive effect of grammar complexity on task performance. The present study focused on computerizing Bollt and Jones's (2000) technique of calculating topological entropy (TE), a quantitative measure of AGL charts' complexity, with the aim of examining associations between grammar systems' TE and learners' AGL task performance. We surveyed the literature and identified 56 previous AGL experiments based on 10 different grammars that met the sampling criteria. Using the automated matrix-lift-action method, we assigned a TE value for each of these 10 previously used AGL systems and examined its correlation with learners' task performance. The meta-regression analysis showed a significant correlation, demonstrating that the complexity effect transcended the different settings and conditions in which the categorization task was performed. The results reinforced the importance of using this new automated tool to uniformly measure grammar systems' complexity when experimenting with and evaluating the findings of AGL studies.

Preparatory neural activity predicts performance on a conflict task.

Science.gov (United States)

Stern, Emily R; Wager, Tor D; Egner, Tobias; Hirsch, Joy; Mangels, Jennifer A

2007-10-24

Advance preparation has been shown to improve the efficiency of conflict resolution. Yet, with little empirical work directly linking preparatory neural activity to the performance benefits of advance cueing, it is not clear whether this relationship results from preparatory activation of task-specific networks, or from activity associated with general alerting processes. Here, fMRI data were acquired during a spatial Stroop task in which advance cues either informed subjects of the upcoming relevant feature of conflict stimuli (spatial or semantic) or were neutral. Informative cues decreased reaction time (RT) relative to neutral cues, and cues indicating that spatial information would be task-relevant elicited greater activity than neutral cues in multiple areas, including right anterior prefrontal and bilateral parietal cortex. Additionally, preparatory activation in bilateral parietal cortex and right dorsolateral prefrontal cortex predicted faster RT when subjects responded to spatial location. No regions were found to be specific to semantic cues at conventional thresholds, and lowering the threshold further revealed little overlap between activity associated with spatial and semantic cueing effects, thereby demonstrating a single dissociation between activations related to preparing a spatial versus semantic task-set. This relationship between preparatory activation of spatial processing networks and efficient conflict resolution suggests that advance information can benefit performance by leading to domain-specific biasing of task-relevant information.

Skylab task and work performance /Experiment M-151 - Time and motion study/

Science.gov (United States)

Kubis, J. F.; Mclaughlin, E. J.

1975-01-01

The primary objective of Experiment M151 was to study the inflight adaptation of Skylab crewmen to a variety of task situations involving different types of activity. A parallel objective was to examine astronaut inflight performance for any behavioral stress effects associated with the working and living conditions of the Skylab environment. Training data provided the basis for comparison of preflight and inflight performance. Efficiency was evaluated through the adaptation function, namely, the relation of performance time over task trials. The results indicate that the initial changeover from preflight to inflight was accompanied by a substantial increase in performance time for most work and task activities. Equally important was the finding that crewmen adjusted rapidly to the weightless environment and became proficient in developing techniques with which to optimize task performance. By the end of the second inflight trial, most of the activities were performed almost as efficiently as on the last preflight trial. The analysis demonstrated the sensitivity of the adaptation function to differences in task and hardware configurations. The function was found to be more regular and less variable inflight than preflight. Translation and control of masses were accomplished easily and efficiently through the rapid development of the arms and legs as subtle guidance and restraint systems.

Self-reported quality of ADL task performance among patients with COPD exacerbations.

Science.gov (United States)

Bendixen, Hans Jørgen; Wæhrens, Eva Ejlersen; Wilcke, Jon Torgny; Sørensen, Lisbeth Villemoes

2014-07-01

Patients suffering from chronic obstructive pulmonary disease (COPD) experience problems in the performance of activities of daily living (ADL) tasks. The objective was to examine the self-reported quality of ADL task performance among COPD patients, and to investigate whether age, gender, and routine COPD characteristics correlate with the self-reported ADL ability. Eighty patients admitted to hospital with COPD exacerbations participated. In a cross-sectional study, the patients' self-reported ADL ability was assessed using the ADL-Interview (ADL-I) instrument. Data concerning age, gender, and routine COPD characteristics were drawn from the patients' medical records. The patients reported being inefficient to markedly inefficient when performing ADL tasks within the personal hygiene, toileting, dressing, household, mobility, and transportation domains. While more than 90% of the participants reported increased effort and/or fatigue when performing the ADL tasks, up to 88% of the participants relied on help from others in the performance of general household chores like cooking and shopping. Self-reported ADL ability did not correlate with age, gender, or routine COPD characteristics. Decreased quality of ADL task performance seemed to be extremely common among COPD patients. Therefore, addressing the problems in individually tailored pulmonary rehabilitation programmes may be advantageous.

Comparison of 3MP medical-grade to 1MP office grade LCD monitors in mammographic diagnostic and perceptual performance

International Nuclear Information System (INIS)

Ong, Aaron; Tan, Shu.; Gledhill, Samuel; Hennessy, Oliver; Lui, Belinda; Lee, Alan; Lemish, Wayne; Styles, Colin; Pun, Emma; Padmanabhan, Meenakshi; Pitman, Alexander G.; Tauro, Paul; Waugh, Paul

2011-01-01

Full text: Picture archiving and communication systems images designed to be viewed on high-resolution medical-grade monitors are routinely viewed on office-grade monitors on the wards or at home. This study aimed to determine whether a statistically significant difference in diagnostic (cancer detection) and perceptual (microcalcification detection) performance exists between 3MP grade and 1MP office-grade monitors. 3MP Dome medical-grade liquid crystal display (LCD) monitors (Planar, Beaverton, OR, USA) were compared to 1MP Dell office-grade LCD monitors (Dell Inc, Round Rock, TX, USA). Eight radiologists (reader experi ence 8-30 years) read the same set of 100 mammograms (23/100 with proven cancers and 52/100 with microcalcifications) presented in random order on three occasions separated by two time intervals of 12 weeks. Reads 1 and 3 utilised 3MP monitors and formed the baseline read. Read 2 utilised 1MP monitors and constituted the experimental read. Reading conditions were standardised. Readers were aware of which monitors they were using. Mul tivariate logistic regression analysis (to account for reader variability and monitor impact) was performed to assess for statistical significance. At a = 5%, confidence intervals analysis comparing the measured parameters between 1MP to 3MP monitors demonstrated no statistically significant difference in diagnostic and perceptual performance for the reader group. In cancer detection (the diagnostic task), reader accuracy remained high irrespective of monitor type. Regression analysis comparing performance with 1MP against 3MP monitors found P values of 0.693 and 0.324 for diagnostic and perceptual performance, respectively. There were no statistically and clinically significant differences between 3MP and 1MP monitors in mammographic diagnostic and perceptual performance. Comparable performance may be due to compensatory behav iour by readers.

High variability impairs motor learning regardless of whether it affects task performance.

Science.gov (United States)

Cardis, Marco; Casadio, Maura; Ranganathan, Rajiv

2018-01-01

Motor variability plays an important role in motor learning, although the exact mechanisms of how variability affects learning are not well understood. Recent evidence suggests that motor variability may have different effects on learning in redundant tasks, depending on whether it is present in the task space (where it affects task performance) or in the null space (where it has no effect on task performance). We examined the effect of directly introducing null and task space variability using a manipulandum during the learning of a motor task. Participants learned a bimanual shuffleboard task for 2 days, where their goal was to slide a virtual puck as close as possible toward a target. Critically, the distance traveled by the puck was determined by the sum of the left- and right-hand velocities, which meant that there was redundancy in the task. Participants were divided into five groups, based on both the dimension in which the variability was introduced and the amount of variability that was introduced during training. Results showed that although all groups were able to reduce error with practice, learning was affected more by the amount of variability introduced rather than the dimension in which variability was introduced. Specifically, groups with higher movement variability during practice showed larger errors at the end of practice compared with groups that had low variability during learning. These results suggest that although introducing variability can increase exploration of new solutions, this may adversely affect the ability to retain the learned solution. NEW & NOTEWORTHY We examined the role of introducing variability during motor learning in a redundant task. The presence of redundancy allows variability to be introduced in different dimensions: the task space (where it affects task performance) or the null space (where it does not affect task performance). We found that introducing variability affected learning adversely, but the amount of

Research study on the effects of illumination on performance of control room tasks

International Nuclear Information System (INIS)

Silverman, E.B.; Horst, R.L.; Parris, H.L.; O'Brien, J.

1990-01-01

The illumination in the control rooms of many operating nuclear plants falls below the levels specified in the NUREG-0700 guidelines. However, these guidelines are based on human perception and performance data which were acquired under laboratory conditions and with tasks very different from those typically found in control rooms. The objective of the present studies was to gather empirical data regarding the levels of illumination sufficient for performing tasks analogous to those performed in control rooms. Several tasks were designed to engage the perceptual and cognitive processes that are representative of actual control room performance. In a computerized laboratory test-bed, subjects scanned edgewise meters, examined hard-copy X-Y plots to discern the value of the displayed function at specific coordinates, and proofread hard-copy plant procedures. In a power plant control room simulator, data were likewise collected in a meter reading task and similar tasks representing elements of specific job-performance measures. For each task, response time and accuracy were measured under a range of illumination levels. Subjective comfort ratings were also obtained for each illumination level. The results from both settings indicated that with decreasing illumination, increased errors and/or longer response times occurred only for levels below ten footcandles, if at all. These data suggest that adequate performance in control room tasks can be achieved at illumination levels below those recommended in NUREG-0700

Structural Correlates of Skilled Performance on a Motor Sequence Task

Directory of Open Access Journals (Sweden)

Christopher J Steele

2012-10-01

Full Text Available The brain regions functionally engaged in motor sequence performance are well established, but the structural characteristics of these regions and the fibre pathways involved have been less well studied. In addition, relatively few studies have combined multiple magnetic resonance imaging (MRI and behavioural performance measures in the same sample. Therefore, the current study used diffusion tensor imaging, probabilistic tractography, and voxel-based morphometry to determine the structural correlates of skilled motor performance. Further, we compared these findings with fMRI results in the same sample. We correlated final performance and rate of improvement measures on a temporal motor sequence task with skeletonised fractional anisotropy (FA and whole brain grey matter (GM volume. Final synchronisation performance was negatively correlated with FA in white matter underlying bilateral sensorimotor cortex – an effect that was mediated by a positive correlation with radial diffusivity. Multi-fibre tractography indicated that this region contained crossing fibres from the corticospinal tract and superior longitudinal fasciculus (SLF. The identified SLF pathway linked parietal and auditory cortical regions that have been shown to be functionally engaged in this task. Thus, we hypothesise that enhanced synchronisation performance on this task may be related to greater fibre integrity of the SLF. Rate of improvement on synchronisation was positively correlated with GM volume in cerebellar lobules HVI and V – regions that showed training-related decreases in activity in the same sample. Taken together, our results link individual differences in brain structure and function to motor sequence performance on the same task. Further, our study illustrates the utility of using multiple MR measures and analysis techniques to specify the interpretation of structural findings.

Ready to rumble: how team personality composition and task conflict interact to improve performance.

Science.gov (United States)

Bradley, Bret H; Klotz, Anthony C; Postlethwaite, Bennett E; Brown, Kenneth G

2013-03-01

Although prior work has proposed a number of conditions under which task conflict in teams may improve performance, composition variables have been left unexplored. Given the effects of personality traits on team processes and outcomes demonstrated in prior work, investigating whether specific personality compositions influence the effect of task conflict on team performance is critical to researchers' understanding of conflict in teams. Our results indicate that team-level averages of both openness to experience and emotional stability function as moderators of the relationship between task conflict and team performance. Specifically, task conflict had a positive impact on performance in teams with high levels of openness or emotional stability; in contrast, task conflict had a negative impact on performance in teams with low levels of openness or emotional stability. Thus, when task conflict emerges, teams composed of members who are open minded or emotionally stable are best able to leverage conflict to improve performance. Implications for theory and practice are discussed.

An Observation Task Chain Representation Model for Disaster Process-Oriented Remote Sensing Satellite Sensor Planning: A Flood Water Monitoring Application

Directory of Open Access Journals (Sweden)

Chao Yang

2018-03-01

Full Text Available An accurate and comprehensive representation of an observation task is a prerequisite in disaster monitoring to achieve reliable sensor observation planning. However, the extant disaster event or task information models do not fully satisfy the observation requirements for the accurate and efficient planning of remote-sensing satellite sensors. By considering the modeling requirements for a disaster observation task, we propose an observation task chain (OTChain representation model that includes four basic OTChain segments and eight-tuple observation task metadata description structures. A prototype system, namely OTChainManager, is implemented to provide functions for modeling, managing, querying, and visualizing observation tasks. In the case of flood water monitoring, we use a flood remote-sensing satellite sensor observation task for the experiment. The results show that the proposed OTChain representation model can be used in modeling process-owned flood disaster observation tasks. By querying and visualizing the flood observation task instances in the Jinsha River Basin, the proposed model can effectively express observation task processes, represent personalized observation constraints, and plan global remote-sensing satellite sensor observations. Compared with typical observation task information models or engines, the proposed OTChain representation model satisfies the information demands of the OTChain and its processes as well as impels the development of a long time-series sensor observation scheme.

The Influence of Math Anxiety, Math Performance, Worry, and Test Anxiety on the Iowa Gambling Task and Balloon Analogue Risk Task.

Science.gov (United States)

Buelow, Melissa T; Barnhart, Wesley R

2017-01-01

Multiple studies have shown that performance on behavioral decision-making tasks, such as the Iowa Gambling Task (IGT) and Balloon Analogue Risk Task (BART), is influenced by external factors, such as mood. However, the research regarding the influence of worry is mixed, and no research has examined the effect of math or test anxiety on these tasks. The present study investigated the effects of anxiety (including math anxiety) and math performance on the IGT and BART in a sample of 137 undergraduate students. Math performance and worry were not correlated with performance on the IGT, and no variables were correlated with BART performance. Linear regressions indicated math anxiety, physiological anxiety, social concerns/stress, and test anxiety significantly predicted disadvantageous selections on the IGT during the transition from decision making under ambiguity to decision making under risk. Implications for clinical evaluation of decision making are discussed. © The Author(s) 2015.

Working memory capacity predicts conflict-task performance.

Science.gov (United States)

Gulbinaite, Rasa; Johnson, Addie

2014-01-01

The relationship between the ability to maintain task goals and working memory capacity (WMC) is firmly established, but evidence for WMC-related differences in conflict processing is mixed. We investigated whether WMC (measured using two complex-span tasks) mediates differences in adjustments of cognitive control in response to conflict. Participants performed a Simon task in which congruent and incongruent trials were equiprobable, but in which the proportion of congruency repetitions (congruent trials followed by congruent trials or incongruent trials followed by incongruent trials) and thus the need for trial-by-trial adjustments in cognitive control varied by block. The overall Simon effect did not depend on WMC capacity. However, for the low-WMC participants the Simon effect decreased as the proportion of congruency repetitions decreased, whereas for the high- and average-WMC participants it was relatively constant across conditions. Distribution analysis of the Simon effect showed more evidence for the inhibition of stimulus location in the low- than in the high-WMC participants, especially when the proportion of congruency repetitions was low. We hypothesize that low-WMC individuals exhibit more interference from task-irrelevant information due to weaker preparatory control prior to stimulus presentation and, thus, stronger reliance on reactive recruitment of cognitive control.

Symbiotic Sensing for Energy-Intensive Tasks in Large-Scale Mobile Sensing Applications.

Science.gov (United States)

Le, Duc V; Nguyen, Thuong; Scholten, Hans; Havinga, Paul J M

2017-11-29

Energy consumption is a critical performance and user experience metric when developing mobile sensing applications, especially with the significantly growing number of sensing applications in recent years. As proposed a decade ago when mobile applications were still not popular and most mobile operating systems were single-tasking, conventional sensing paradigms such as opportunistic sensing and participatory sensing do not explore the relationship among concurrent applications for energy-intensive tasks. In this paper, inspired by social relationships among living creatures in nature, we propose a symbiotic sensing paradigm that can conserve energy, while maintaining equivalent performance to existing paradigms. The key idea is that sensing applications should cooperatively perform common tasks to avoid acquiring the same resources multiple times. By doing so, this sensing paradigm executes sensing tasks with very little extra resource consumption and, consequently, extends battery life. To evaluate and compare the symbiotic sensing paradigm with the existing ones, we develop mathematical models in terms of the completion probability and estimated energy consumption. The quantitative evaluation results using various parameters obtained from real datasets indicate that symbiotic sensing performs better than opportunistic sensing and participatory sensing in large-scale sensing applications, such as road condition monitoring, air pollution monitoring, and city noise monitoring.

Symbiotic Sensing for Energy-Intensive Tasks in Large-Scale Mobile Sensing Applications

Science.gov (United States)

Scholten, Hans; Havinga, Paul J. M.

2017-01-01

Energy consumption is a critical performance and user experience metric when developing mobile sensing applications, especially with the significantly growing number of sensing applications in recent years. As proposed a decade ago when mobile applications were still not popular and most mobile operating systems were single-tasking, conventional sensing paradigms such as opportunistic sensing and participatory sensing do not explore the relationship among concurrent applications for energy-intensive tasks. In this paper, inspired by social relationships among living creatures in nature, we propose a symbiotic sensing paradigm that can conserve energy, while maintaining equivalent performance to existing paradigms. The key idea is that sensing applications should cooperatively perform common tasks to avoid acquiring the same resources multiple times. By doing so, this sensing paradigm executes sensing tasks with very little extra resource consumption and, consequently, extends battery life. To evaluate and compare the symbiotic sensing paradigm with the existing ones, we develop mathematical models in terms of the completion probability and estimated energy consumption. The quantitative evaluation results using various parameters obtained from real datasets indicate that symbiotic sensing performs better than opportunistic sensing and participatory sensing in large-scale sensing applications, such as road condition monitoring, air pollution monitoring, and city noise monitoring. PMID:29186037

Symbiotic Sensing for Energy-Intensive Tasks in Large-Scale Mobile Sensing Applications

Directory of Open Access Journals (Sweden)

Duc V. Le

2017-11-01

Full Text Available Energy consumption is a critical performance and user experience metric when developing mobile sensing applications, especially with the significantly growing number of sensing applications in recent years. As proposed a decade ago when mobile applications were still not popular and most mobile operating systems were single-tasking, conventional sensing paradigms such as opportunistic sensing and participatory sensing do not explore the relationship among concurrent applications for energy-intensive tasks. In this paper, inspired by social relationships among living creatures in nature, we propose a symbiotic sensing paradigm that can conserve energy, while maintaining equivalent performance to existing paradigms. The key idea is that sensing applications should cooperatively perform common tasks to avoid acquiring the same resources multiple times. By doing so, this sensing paradigm executes sensing tasks with very little extra resource consumption and, consequently, extends battery life. To evaluate and compare the symbiotic sensing paradigm with the existing ones, we develop mathematical models in terms of the completion probability and estimated energy consumption. The quantitative evaluation results using various parameters obtained from real datasets indicate that symbiotic sensing performs better than opportunistic sensing and participatory sensing in large-scale sensing applications, such as road condition monitoring, air pollution monitoring, and city noise monitoring.

Discrepancy of performance among working memory-related tasks in autism spectrum disorders was caused by task characteristics, apart from working memory, which could interfere with task execution.

Science.gov (United States)

Nakahachi, Takayuki; Iwase, Masao; Takahashi, Hidetoshi; Honaga, Eiko; Sekiyama, Ryuji; Ukai, Satoshi; Ishii, Ryouhei; Ishigami, Wataru; Kajimoto, Osami; Yamashita, Ko; Hashimoto, Ryota; Tanii, Hisashi; Shimizu, Akira; Takeda, Masatoshi

2006-06-01

Working memory performance has been inconsistently reported in autism spectrum disorders (ASD). Several studies in ASD have found normal performance in digit span and poor performance in digit symbol task although these are closely related with working memory. It is assumed that poor performance in digit symbol could be explained by confirmatory behavior, which is induced due to the vague memory representation of number-symbol association. Therefore it was hypothesized that the performance of working memory task, in which vagueness did not cause confirmatory behavior, would be normal in ASD. For this purpose, the Advanced Trail Making Test (ATMT) was used. The performance of digit span, digit symbol and ATMT was compared between ASD and normal control. The digit span, digit symbol and ATMT was given to 16 ASD subjects and 28 IQ-, age- and sex-matched control subjects. The scores of these tasks were compared. A significantly lower score for ASD was found only in digit symbol compared with control subjects. There were no significant difference in digit span and working memory estimated by ATMT. Discrepancy of scores among working memory-related tasks was demonstrated in ASD. Poor digit symbol performance, normal digit span and normal working memory in ATMT implied that ASD subjects would be intact in working memory itself, and that superficial working memory dysfunction might be observed due to confirmatory behavior in digit symbol. Therefore, to evaluate working memory in ASD, tasks that could stimulate psychopathology specific to ASD should be avoided.

Effects of the Use of Social Network Sites on Task Performance: Toward a Sustainable Performance in a Distracting Work Environment

Directory of Open Access Journals (Sweden)

Jinyoung Min

2017-12-01

Full Text Available As the use of social network sites (SNS has become increasingly prevalent, its effect on sustainable performance has received much attention. The existing literature has taken either a positive or negative view of SNS, arguing that it either decreases performance by taking time and effort away from work, or increases performance by providing social benefits for enhancing performance. In contrast, this experimental study, investigates how SNS use can disturb or enhance the performance of different types of tasks differently, thus influencing the sustainability of task performance. Based on distraction-conflict theory, this study distinguishes between simple and complex tasks, examines the role of SNS, and analyzes data including electroencephalography data captured by a brain-computer interface. The results show that task performance can be sustainable such that SNS use positively influences performance when participants are engaged in a simple task and influences performance neither positively nor negatively when participants are engaged in a complex task. The study finds the former result is attributable to the positive effect of the psychological arousal induced by SNS use and the latter result to the negative effect of the psychological arousal offsetting the positive effect of reduced stress resulting from SNS use.

Roles of Working Memory Performance and Instructional Strategy in Complex Cognitive Task Performance

Science.gov (United States)

Cevik, V.; Altun, A.

2016-01-01

This study aims to investigate how working memory (WM) performances and instructional strategy choices affect learners' complex cognitive task performance in online environments. Three different e-learning environments were designed based on Merrill's (2006a) model of instructional strategies. The lack of experimental research on his framework is…

Thermal effects on human performance in office environment measured by integrating task speed and accuracy

DEFF Research Database (Denmark)

Lan, Li; Wargocki, Pawel; Lian, Zhiwei

2014-01-01

We have proposed a method in which the speed and accuracy can be integrated into one metric of human performance. This was achieved by designing a performance task in which the subjects receive feedback on their performance by informing them whether they have committed errors, and if did, they can......, 12 subjects performed tasks under two thermal conditions (neutral & warm) repeatedly. The tasks were presented with and without feedback on errors committed, as outlined above. The results indicate that there was a greater decrease in task performance due to thermal discomfort when feedback was given......, compared to the performance of tasks presented without feedback....

Measuring working memory in aphasia: Comparing performance on complex span and N-back tasks

Directory of Open Access Journals (Sweden)

Maria Ivanova

2014-04-01

No significant correlations were observed between performance on complex span task and N-back tasks.Furthermore, performance on the modified listening span was related to performance on the comprehension subtest of the QASA, while no relationship was found for 2-back and 0-back tasks.Our results mirror studies in healthy controls that demonstrated no relationship between performance on the two tasks(Jaeggi et al., 2010; Kane et al., 2007. Thus although N-back tasks seem similar to traditional complex span measures and may also index abilities related to cognitive processing, the evidence to date does not warrant their direct association with the construct of WM. Implications for future investigation of cognitive deficits in aphasia will be discussed.

Features of Solving Retrospective (Successive Tasks of the Monitoring Subsystem in Systems for Strategic Control of the Regional Structure and Territorial Organization in the Agri-Food Sphere

Directory of Open Access Journals (Sweden)

Tkachenko Serhii A.

2016-02-01

Full Text Available The given article highlights features of solving retrospective (successive tasks of monitoring production and economic activity of the territorial-production system through a profound using of scientific principles in the developed and introduced enlarged block diagram of the control system for a functionally advanced solution of the task of monitoring labour force turnover at the entity in the agri-food sphere. Solving the task of monitoring the labour force turnover in the territorial-production system by means of electronic digital machines allows: to reduce the complexity of calculations performed by employees of Human Resources Department and make time for other research and control functions; to accelerate submission of necessary accounting and economic as well as analytical information on the labour force turnover at the entity in the agri-food sphere to consumers; increase the quality of accounting and economic as well as analytical information by eliminating errors, which occur at manual calculation; to build a real scientific basis for developing measures of technical, organizational and socio-economic nature aimed at reducing the labour force turnover. The given list of issues solved at development of the monitoring subsystem in strategic control systems of the regional structure and territorial organization of the agri-food sphere is not complete, the use of industrial methods for creating a monitoring subsystem, training specialists and a number of other issues, which are no less important, should be mentioned as well.

Modular Software Performance Monitoring

CERN Document Server

Kruse, D F

2011-01-01

CPU clock frequency is not likely to be increased significantly in the coming years, and data analysis speed can be improved by using more processors or buying new machines, only if one is willing to change the paradigm to a parallel one. Therefore, performance monitoring procedures and tools are needed to help programmers to optimize existing software running on current and future hardware. Low level information from hardware performance counters is vital to spot specific performance problems slowing program execution. HEP software is often huge and complex, and existing tools are unable to give results with the required granularity. We will report on the approach we have chose to solve this problem that involves decomposing the application into parts and monitoring each of them separately. Both counting and sampling methods are used to allow an analysis with the required custom granularity: from global level, up to the function level. A set of tools (based on perfmon2 – a software interface to hardware co...

Predictors of Processing-Based Task Performance in Bilingual and Monolingual Children

Science.gov (United States)

Buac, Milijana; Gross, Megan; Kaushanskaya, Margarita

2016-01-01

In the present study we examined performance of bilingual Spanish-English-speaking and monolingual English-speaking school-age children on a range of processing-based measures within the framework of Baddeley’s working memory model. The processing-based measures included measures of short-term memory, measures of working memory, and a novel word-learning task. Results revealed that monolinguals outperformed bilinguals on the short-term memory tasks but not the working memory and novel word-learning tasks. Further, children’s vocabulary skills and socioeconomic status (SES) were more predictive of processing-based task performance in the bilingual group than the monolingual group. Together, these findings indicate that processing-based tasks that engage verbal working memory rather than short-term memory may be better-suited for diagnostic purposes with bilingual children. However, even verbal working memory measures are sensitive to bilingual children’s language-specific knowledge and demographic characteristics, and therefore may have limited clinical utility. PMID:27179914

The Effects of Distraction on Cognitive Task Performance during Toddlerhood

Science.gov (United States)

Wyss, Nancy M.; Kannass, Kathleen N.; Haden, Catherine A.

2013-01-01

We investigated the effects of distraction on attention and task performance during toddlerhood. Thirty toddlers (24- to 26-month-olds) completed different tasks (2 of each: categorization, problem solving, memory, free play) in one of two conditions: No Distraction or Distraction. The results revealed that the distractor had varying effects on…

The development of on-line thermal performance monitors in Nuclear Electric Company's stations

International Nuclear Information System (INIS)

Conner, A.S.

1992-01-01

The paper examines the economic benefits of using on-line monitoring techniques in assisting Station Staff with the task of optimising the efficient use of reactor fuel. The role of thermal performance monitoring for detecting changes in plant condition is also examined and the way in which the data can be used by engineers to assist with the preparation of operating and maintenance programmes. To enable genuine gradual changes in plant performance to be detected when operating against a background of changing plant signal accuracy conditions, plant transducers have to be calibrated on a regular basis. This can be both costly and labour intensive. To reduce this requirement for regular calibrations, an automatic software signal verification program has been developed for use in on-line monitoring schemes. It forms part of the total unit performance calculation package and uses a whole plant model to verify plant signals. All plant signals used to calculate unit heat rate are verified typically every 15 minutes with signals going outside predetermined limits being automatically reported to the user. The program is interactive allowing the user to interrogate the condition of the signal, with respect to both its error magnitude and rate of drift outside signal limits. The program runs in real time mode on a Workstation connected directly to the plant

A comparison of the effects of a secondary task and lorazepam on cognitive performance.

Science.gov (United States)

File, S E

1992-01-01

In order to test whether the lorazepam-induced impairments in a variety of cognitive tasks were similar to those of divided attention, the effects of lorazepam (2.5 mg) in healthy volunteers were compared with those requiring subjects to perform an additional task (detecting silences superimposed onto classical music). Neither treatment impaired implicit memory or judgements of frequency. Both treatments impaired performance in tests of speed, lorazepam having the greatest effect on number cancellation and the additional task having the greatest effect on simple reaction time. Both treatments impaired performance in a coding task, in a test of explicit episodic memory and in judgements of recency (indicating impaired coding of contextual information). Lorazepam significantly reduced performance in a word completion task, but this was unimpaired in the group performing the additional task. In general, the pattern of results suggests that there are similarities between the effects of divided attention and lorazepam treatment, and that lorazepam-induced cognitive impairments are not restricted to explicit tests of episodic memory.

Exploring the Relationship of Task Performance and Physical and Cognitive Fatigue During a Daylong Light Precision Task.

Science.gov (United States)

Yung, Marcus; Manji, Rahim; Wells, Richard P

2017-11-01

Our aim was to explore the relationship between fatigue and operation system performance during a simulated light precision task over an 8-hr period using a battery of physical (central and peripheral) and cognitive measures. Fatigue may play an important role in the relationship between poor ergonomics and deficits in quality and productivity. However, well-controlled laboratory studies in this area have several limitations, including the lack of work relevance of fatigue exposures and lack of both physical and cognitive measures. There remains a need to understand the relationship between physical and cognitive fatigue and task performance at exposure levels relevant to realistic production or light precision work. Errors and fatigue measures were tracked over the course of a micropipetting task. Fatigue responses from 10 measures and errors in pipetting technique, precision, and targeting were submitted to principal component analysis to descriptively analyze features and patterns. Fatigue responses and error rates contributed to three principal components (PCs), accounting for 50.9% of total variance. Fatigue responses grouped within the three PCs reflected central and peripheral upper extremity fatigue, postural sway, and changes in oculomotor behavior. In an 8-hr light precision task, error rates shared similar patterns to both physical and cognitive fatigue responses, and/or increases in arousal level. The findings provide insight toward the relationship between fatigue and operation system performance (e.g., errors). This study contributes to a body of literature documenting task errors and fatigue, reflecting physical (both central and peripheral) and cognitive processes.

Do absorption and realistic distraction influence performance of component task surgical procedure?

Science.gov (United States)

Pluyter, Jon R; Buzink, Sonja N; Rutkowski, Anne-F; Jakimowicz, Jack J

2010-04-01

Surgeons perform complex tasks while exposed to multiple distracting sources that may increase stress in the operating room (e.g., music, conversation, and unadapted use of sophisticated technologies). This study aimed to examine whether such realistic social and technological distracting conditions may influence surgical performance. Twelve medical interns performed a laparoscopic cholecystectomy task with the Xitact LC 3.0 virtual reality simulator under distracting conditions (exposure to music, conversation, and nonoptimal handling of the laparoscope) versus nondistracting conditions (control condition) as part of a 2 x 2 within-subject experimental design. Under distracting conditions, the medical interns showed a significant decline in task performance (overall task score, task errors, and operating time) and significantly increased levels of irritation toward both the assistant handling the laparoscope in a nonoptimal way and the sources of social distraction. Furthermore, individual differences in cognitive style (i.e., cognitive absorption and need for cognition) significantly influenced the levels of irritation experienced by the medical interns. The results suggest careful evaluation of the social and technological sources of distraction in the operation room to reduce irritation for the surgeon and provision of proper preclinical laparoscope navigation training to increase security for the patient.

Older Adults Pay an Additional Cost When Texting and Walking: Effects of Age, Environment, and Use of Mixed Reality on Dual-Task Performance.

Science.gov (United States)

Krasovsky, Tal; Weiss, Patrice L; Kizony, Rachel

2018-04-06

Texting while walking (TeWW) has become common among people of all ages, and mobile phone use during gait is increasingly associated with pedestrian injury. Although dual-task walking performance is known to decline with age, data regarding the effect of age on dual-task performance in ecological settings are limited. The objective of this study was to evaluate the effect of age, environment (indoors/outdoors), and mixed reality (merging of real and virtual environments) on TeWW performance. A cross-sectional design was used. Young (N = 30; 27.8 ± 4.4 years) and older (N = 20; 68.9 ± 3.9 years) adults performed single and dual-task texting and walking indoors and outdoors, with and without a mixed reality display. Participants also completed evaluations of visual scanning and cognitive flexibility (Trail Making Test) and functional mobility (Timed Up and Go). Indoors, similar interference to walking and texting occurred for both groups, but only older adults' gait variability increased under dual task conditions. Outdoors, TeWW was associated with larger age-related differences in gait variability, texting accuracy, and gait dual-task costs. Young adults with better visual scanning and cognitive flexibility performed TeWW with lower gait costs (r = 0.52 to r = 0.65). The mixed reality display was unhelpful and did not modify walking or texting. Older adults tested in this study were relatively high-functioning. Gaze of participants was not directly monitored. Although young and older adults possess the resources necessary for TeWW, older adults pay an additional "price" when dual-tasking, especially outdoors. TeWW may have potential as an ecologically-valid assessment and/or an intervention paradigm for dual task performance among older adults as well as for clinical populations.

Game elements improve performance in a working memory training task

OpenAIRE

Manuel Ninaus; Gonçalo Pereira; René Stefitz; Rui Prada; Ana Paiva; Christa Neuper; Guilherme Wood

2015-01-01

The utilization of game elements in a non-game context is currently used in a vast range of different domains. However, research on game elements’ effects in cognitive tasks is still sparse. Thus, in this study we implemented three game elements, namely, progress bar, level indicator, and a thematic setting, in a working memory training task. We evaluated the impact of game elements on user performance and perceived state of flow when compared to a conventional version of the task. Participan...

A key role for experimental task performance: effects of math talent, gender and performance on the neural correlates of mental rotation.

Science.gov (United States)

Hoppe, Christian; Fliessbach, Klaus; Stausberg, Sven; Stojanovic, Jelena; Trautner, Peter; Elger, Christian E; Weber, Bernd

2012-02-01

The neurophysiological mechanisms underlying superior cognitive performance are a research area of high interest. The majority of studies on the brain-performance relationship assessed the effects of capability-related group factors (e.g. talent, gender) on task-related brain activations while only few studies examined the effect of the inherent experimental task performance factor. In this functional MRI study, we combined both approaches and simultaneously assessed the effects of three relatively independent factors on the neurofunctional correlates of mental rotation in same-aged adolescents: math talent (gifted/controls: 17/17), gender (male/female: 16/18) and experimental task performance (median split on accuracy; high/low: 17/17). Better experimental task performance of mathematically gifted vs. control subjects and male vs. female subjects validated the selected paradigm. Activation of the inferior parietal lobule (IPL) was identified as a common effect of mathematical giftedness, gender and experimental task performance. However, multiple linear regression analyses (stepwise) indicated experimental task performance as the only predictor of parietal activations. In conclusion, increased activation of the IPL represents a positive neural correlate of mental rotation performance, irrespective of but consistent with the obtained neurocognitive and behavioral effects of math talent and gender. As experimental performance may strongly affect task-related activations this factor needs to be considered in capability-related group comparison studies on the brain-performance relationship. Copyright © 2011 Elsevier Inc. All rights reserved.

The effect of single-task and dual-task balance exercise programs on balance performance in adults with osteoporosis: a randomized controlled preliminary trial.

Science.gov (United States)

Konak, H E; Kibar, S; Ergin, E S

2016-11-01

Osteoporosis is a serious disease characterized by muscle weakness in the lower extremities, shortened length of trunk, and increased dorsal kyphosis leading to poor balance performance. Although balance impairment increases in adults with osteoporosis, falls and fall-related injuries have been shown to occur mainly during the dual-task performance. Several studies have shown that dual-task performance was improved with specific repetitive dual-task exercises. The aims of this study were to compare the effect of single- and dual-task balance exercise programs on static balance, dynamic balance, and activity-specific balance confidence in adults with osteoporosis and to assess the effectiveness of dual-task balance training on gait speed under dual-task conditions. Older adults (N = 42) (age range, 45-88 years) with osteoporosis were randomly assigned into two groups. Single-task balance training group was given single-task balance exercises for 4 weeks, whereas dual-task balance training group received dual-task balance exercises. Participants received 45-min individualized training session, three times a week. Static balance was evaluated by one-leg stance (OLS) and a kinesthetic ability trainer (KAT) device. Dynamic balance was measured by the Berg Balance Scale (BBS), Time Up and Go (TUG) test, and gait speed. Self-confidence was assessed with the Activities-specific Balance Confidence (ABC-6) scale. Assessments were performed at baseline and after the 4-week program. At the end of the treatment periods, KAT score, BBS score, time in OLS and TUG, gait speeds under single- and dual-task conditions, and ABC-6 scale scores improved significantly in all patients (p gait speeds under single- and dual-task conditions showed significantly greater improvement in the dual-task balance training group than in the single-task balance training group (p gait speeds showed greater improvement following the application of a specific type of dual-task exercise programs

Early Numerical Competence and Number Line Task Performance in Kindergarteners

Science.gov (United States)

Fanari, Rachele; Meloni, Carla; Massidda, Davide

2017-01-01

This work aims to evaluate the relationship between early numerical competence in kindergarteners and their numerical representations as measured by the number line task (NLT). Thirty-four 5-year-old children participated in the study. Children's early performance on symbolic and non-symbolic numerical tasks was considered to determine which was a…

Impact of time on task on ADHD patient's performances in a virtual classroom.

Science.gov (United States)

Bioulac, Stéphanie; Lallemand, Stéphanie; Rizzo, Albert; Philip, Pierre; Fabrigoule, Colette; Bouvard, Manuel Pierre

2012-09-01

Use of virtual reality tool is interesting for the evaluation of Attention Deficit/Hyperactivity Disorder (ADHD) patients. The virtual environment offers the opportunity to administer controlled task like the typical neuropsychological tools, but in an environment much more like standard classroom. Previous studies showed that a virtual classroom was able to distinguish performances of children with and without ADHD, but the evolution of performances over time has not been explored. The aim of this work was to study time on task effects on performances of ADHD children compared to controls in a virtual classroom (VC). 36 boys aged from 7 to 10 years completed the virtual classroom task. We compared the performance of the children diagnosed with ADHD with those of the control children. We also compared attentional performances recorded in the virtual classroom with measures of the Continuous Performance Test (CPT II). Our results showed that patients differ from control subjects in term of time effect on performances. If controls sustained performances over time in the virtual reality task, ADHD patients showed a significant performance decrement over time. Performances at the VC correlated with CPT II measures. ADHD children are vulnerable to a time on task effect on performances which could explain part of their difficulties. Virtual reality is a reliable method to test ADHD children ability to sustain performances over time. Copyright © 2012 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Children exhibit different performance patterns in explicit and implicit theory of mind tasks.

Science.gov (United States)

Oktay-Gür, Nese; Schulz, Alexandra; Rakoczy, Hannes

2018-04-01

Three studies tested scope and limits of children's implicit and explicit theory of mind. In Studies 1 and 2, three- to six-year-olds (N = 84) were presented with closely matched explicit false belief tasks that differed in whether or not they required an understanding of aspectuality. Results revealed that children performed equally well in the different tasks, and performance was strongly correlated. Study 3 tested two-year-olds (N = 81) in implicit interactive versions of these tasks and found evidence for dis-unity: children performed competently only in those tasks that did not require an understanding of aspectuality. Taken together, the present findings suggest that early implicit and later explicit theory of mind tasks may tap different forms of cognitive capacities. Copyright © 2018 Elsevier B.V. All rights reserved.

Motor-cognitive dual-task performance: effects of a concurrent motor task on distinct components of visual processing capacity

OpenAIRE

Künstler, E. C. S.; Finke, K.; Günther, A.; Klingner, C.; Witte, O.; Bublak, P.

2017-01-01

Dual tasking, or the simultaneous execution of two continuous tasks, is frequently associated with a performance decline that can be explained within a capacity sharing framework. In this study, we assessed the effects of a concurrent motor task on the efficiency of visual information uptake based on the ‘theory of visual attention’ (TVA). TVA provides parameter estimates reflecting distinct components of visual processing capacity: perceptual threshold, visual processing speed, and visual sh...

Dual Arm Work Package performance estimates and telerobot task network simulation

International Nuclear Information System (INIS)

Draper, J.V.

1997-01-01

This paper describes the methodology and results of a network simulation study of the Dual Arm Work Package (DAWP), to be employed for dismantling the Argonne National Laboratory CP-5 reactor. The development of the simulation model was based upon the results of a task analysis for the same system. This study was performed by the Oak Ridge National Laboratory (ORNL), in the Robotics and Process Systems Division. Funding was provided the US Department of Energy's Office of Technology Development, Robotics Technology Development Program (RTDP). The RTDP is developing methods of computer simulation to estimate telerobotic system performance. Data were collected to provide point estimates to be used in a task network simulation model. Three skilled operators performed six repetitions of a pipe cutting task representative of typical teleoperation cutting operations

Sustained and transient attention in the Continuous Performance Task

NARCIS (Netherlands)

Smid, HGOM; de Witte, MR; Homminga, [No Value; van den Bosch, RJ

One of the most frequently applied methods to study abnormal cognition is the Continuous Performance Task (CPT). It is unclear, however, which cognitive functions are engaged in normal CPT performance. The aims of the present study were to identify the neurocognitive functions engaged in the main

Do absorption and realistic distraction influence performance of component task surgical procedure?

OpenAIRE

Pluyter, J.R.; Buzink, S.N.; Rutkowski, A.F.; Jakimowicz, J.J.

2009-01-01

Background. Surgeons perform complex tasks while exposed to multiple distracting sources that may increase stress in the operating room (e.g., music, conversation, and unadapted use of sophisticated technologies). This study aimed to examine whether such realistic social and technological distracting conditions may influence surgical performance. Methods. Twelve medical interns performed a laparoscopic cholecystectomy task with the Xitact LC 3.0 virtual reality simulator under distracting con...