WorldWideScience

Sample records for performance assessment tasks

  1. Performance assessment task team progress report

    International Nuclear Information System (INIS)

    Wood, D.E.; Curl, R.U.; Armstrong, D.R.; Cook, J.R.; Dolenc, M.R.; Kocher, D.C.; Owens, K.W.; Regnier, E.P.; Roles, G.W.; Seitz, R.R.

    1994-05-01

    The U.S. Department of Energy (DOE) Headquarters EM-35, established a Performance Assessment Task Team (referred to as the Team) to integrate the activities of the sites that are preparing performance assessments (PAs) for disposal of new low-level waste, as required by Chapter III of DOE Order 5820.2A, open-quotes Low-Level Waste Managementclose quotes. The intent of the Team is to achieve a degree of consistency among these PAs as the analyses proceed at the disposal sites. The Team's purpose is to recommend policy and guidance to the DOE on issues that impact the PAs, including release scenarios and parameters, so that the approaches are as consistent as possible across the DOE complex. The Team has identified issues requiring attention and developed discussion papers for those issues. Some issues have been completed, and the recommendations are provided in this document. Other issues are still being discussed, and the status summaries are provided in this document. A major initiative was to establish a subteam to develop a set of test scenarios and parameters for benchmarking codes in use at the various sites. The activities of the Team are reported here through December 1993

  2. 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.

  3. 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…

  4. Assessment Training Effects on Student Assessment Skills and Task Performance in a Technology-Facilitated Peer Assessment

    Science.gov (United States)

    Liu, Xiongyi; Li, Lan

    2014-01-01

    This study examines the impact of an assessment training module on student assessment skills and task performance in a technology-facilitated peer assessment. Seventy-eight undergraduate students participated in the study. The participants completed an assessment training exercise, prior to engaging in peer-assessment activities. During the…

  5. Processing Resources in Attention, Dual Task Performance, and Workload Assessment.

    Science.gov (United States)

    1981-07-01

    levels of processing in encoding and memory ( Craik & Lockhart , 1972) employs the capacity metaphore when describing the amount of processing ...depending upon the nature of a paired task. Second, encoding or rehearsal of verbal material may differ in the "depth of processing " ( Craik & Lockhart ...F.I.M., & Lockhart , F.S. Levels of processing : A framework for mem- ory research. Journal of Verbal Learning & Verbal Behavior, 1972, 11, 671-684.

  6. The Assessment of Military Multitasking Performance: Validation of a Dual-Task and Multitask Protocol

    Science.gov (United States)

    2014-08-01

    multitasks using healthy control and SM with diagnosed mTBI. Approach: Inter-rater reliability and assessment of training requirements for expert...developers piloted the revised multitask assessment in a healthy population to assess IRR. Given the an- ticipated variability in task performance between...1 AD_________________ Award Number: Contract W81XWH-12-2-0070 TITLE: Annual Report: The Assessment of Military Multitasking

  7. 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

  8. Performance Assessment and the Components of the Oral Construct across Different Tasks and Rater Groups.

    Science.gov (United States)

    Chalhoub-Deville, Micheline

    This study investigated whether different groups of native speakers assess second language learners' language skills differently for three elicitation techniques. Subjects were six learners of college-level Arabic as a second language, tape-recorded performing three tasks: participating in a modified oral proficiency interview, narrating a picture…

  9. 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.

  10. Assessment of Joystick control during the performance of powered wheelchair driving tasks

    Directory of Open Access Journals (Sweden)

    Routhier François

    2011-05-01

    Full Text Available Abstract Background Powered wheelchairs are essential for many individuals who have mobility impairments. Nevertheless, if operated improperly, the powered wheelchair poses dangers to both the user and to those in its vicinity. Thus, operating a powered wheelchair with some degree of proficiency is important for safety, and measuring driving skills becomes an important issue to address. The objective of this study was to explore the discriminate validity of outcome measures of driving skills based on joystick control strategies and performance recorded using a data logging system. Methods We compared joystick control strategies and performance during standardized driving tasks between a group of 10 expert and 13 novice powered wheelchair users. Driving tasks were drawn from the Wheelchair Skills Test (v. 4.1. Data from the joystick controller were collected on a data logging system. Joystick control strategies and performance outcome measures included the mean number of joystick movements, time required to complete tasks, as well as variability of joystick direction. Results In simpler tasks, the expert group's driving skills were comparable to those of the novice group. Yet, in more difficult and spatially confined tasks, the expert group required fewer joystick movements for task completion. In some cases, experts also completed tasks in approximately half the time with respect to the novice group. Conclusions The analysis of joystick control made it possible to discriminate between novice and expert powered wheelchair users in a variety of driving tasks. These results imply that in spatially confined areas, a greater powered wheelchair driving skill level is required to complete tasks efficiently. Based on these findings, it would appear that the use of joystick signal analysis constitutes an objective tool for the measurement of powered wheelchair driving skills. This tool may be useful for the clinical assessment and training of powered

  11. Assessment of Spatial Navigation and Docking Performance During Simulated Rover Tasks

    Science.gov (United States)

    Wood, S. J.; Dean, S. L.; De Dios, Y. E.; Moore, S. T.

    2010-01-01

    INTRODUCTION: Following long-duration exploration transits, pressurized rovers will enhance surface mobility to explore multiple sites across Mars and other planetary bodies. Multiple rovers with docking capabilities are envisioned to expand the range of exploration. However, adaptive changes in sensorimotor and cognitive function may impair the crew s ability to safely navigate and perform docking tasks shortly after transition to the new gravitoinertial environment. The primary goal of this investigation is to quantify post-flight decrements in spatial navigation and docking performance during a rover simulation. METHODS: Eight crewmembers returning from the International Space Station will be tested on a motion simulator during four pre-flight and three post-flight sessions over the first 8 days following landing. The rover simulation consists of a serial presentation of discrete tasks to be completed within a scheduled 10 min block. The tasks are based on navigating around a Martian outpost spread over a 970 sq m terrain. Each task is subdivided into three components to be performed as quickly and accurately as possible: (1) Perspective taking: Subjects use a joystick to indicate direction of target after presentation of a map detailing current orientation and location of the rover with the task to be performed. (2) Navigation: Subjects drive the rover to the desired location while avoiding obstacles. (3) Docking: Fine positioning of the rover is required to dock with another object or align a camera view. Overall operator proficiency will be based on how many tasks the crewmember can complete during the 10 min time block. EXPECTED RESULTS: Functionally relevant testing early post-flight will develop evidence regarding the limitations to early surface operations and what countermeasures are needed. This approach can be easily adapted to a wide variety of simulated vehicle designs to provide sensorimotor assessments for other operational and civilian populations.

  12. Assessing the role of memory in preschoolers' performance on episodic foresight tasks.

    Science.gov (United States)

    Atance, Cristina M; Sommerville, Jessica A

    2014-01-01

    A total of 48 preschoolers (ages 3, 4, and 5) received four tasks modelled after prior work designed to assess the development of "episodic foresight". For each task, children encountered a problem in one room and, after a brief delay, were given the opportunity in a second room to select an item to solve the problem. Importantly, after selecting an item, children were queried about their memory for the problem. Age-related changes were found both in children's ability to select the correct item and their ability to remember the problem. However, when we controlled for children's memory for the problem, there were no longer significant age-related changes on the item choice measure. These findings suggest that age-related changes in children's performance on these tasks are driven by improvements in children's memory versus improvements in children's future-oriented thinking or "foresight" per se. Our results have important implications for how best to structure tasks to measure children's episodic foresight, and also for the relative role of memory in this task and in episodic foresight more broadly.

  13. 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....

  14. Utility as a rationale for choosing observer performance assessment paradigms for detection tasks in medical imaging.

    Science.gov (United States)

    Wunderlich, Adam; Abbey, Craig K

    2013-11-01

    Studies of lesion detectability are often carried out to evaluate medical imaging technology. For such studies, several approaches have been proposed to measure observer performance, such as the receiver operating characteristic (ROC), the localization ROC (LROC), the free-response ROC (FROC), the alternative free-response ROC (AFROC), and the exponentially transformed FROC (EFROC) paradigms. Therefore, an experimenter seeking to carry out such a study is confronted with an array of choices. Traditionally, arguments for different approaches have been made on the basis of practical considerations (statistical power, etc.) or the gross level of analysis (case-level or lesion-level). This article contends that a careful consideration of utility should form the rationale for matching the assessment paradigm to the clinical task of interest. In utility theory, task performance is commonly evaluated with total expected utility, which integrates the various event utilities against the probability of each event. To formalize the relationship between expected utility and the summary curve associated with each assessment paradigm, the concept of a "natural" utility structure is proposed. A natural utility structure is defined for a summary curve when the variables associated with the summary curve axes are sufficient for computing total expected utility, assuming that the disease prevalence is known. Natural utility structures for ROC, LROC, FROC, AFROC, and EFROC curves are introduced, clarifying how the utilities of correct and incorrect decisions are aggregated by summary curves. Further, conditions are given under which general utility structures for localization-based methodologies reduce to case-based assessment. Overall, the findings reveal how summary curves correspond to natural utility structures of diagnostic tasks, suggesting utility as a motivating principle for choosing an assessment paradigm.

  15. Investigating Assessment Bias for Constructed Response Explanation Tasks: Implications for Evaluating Performance Expectations for Scientific Practice

    Science.gov (United States)

    Federer, Meghan Rector

    frequently incorporate multivalent concepts into explanations of change, resulting in explanatory practices that were scientifically non-normative. However, use of follow-up question approaches was found to resolve this source of bias and thereby increase the validity of inferences about student understanding. The second study focused on issues of item and instrument structure, specifically item feature effects and item position effects, which have been shown to influence measures of student performance across assessment tasks. Results indicated that, along the instrument item sequence, items with similar surface features produced greater sequencing effects than sequences of items with dissimilar surface features. This bias could be addressed by use of a counterbalanced design (i.e., Latin Square) at the population level of analysis. Explanation scores were also highly correlated with student verbosity, despite verbosity being an intrinsically trivial aspect of explanation quality. Attempting to standardize student response length was one proposed solution to the verbosity bias. The third study explored gender differences in students' performance on constructed-response explanation tasks using impact (i.e., mean raw scores) and differential item function (i.e., item difficulties) patterns. While prior research in science education has suggested that females tend to perform better on constructed-response items, the results of this study revealed no overall differences in gender achievement. However, evaluation of specific item features patterns suggested that female respondents have a slight advantage on unfamiliar explanation tasks. That is, male students tended to incorporate fewer scientifically normative concepts (i.e., key concepts) than females for unfamiliar taxa. Conversely, females tended to incorporate more scientifically non-normative ideas (i.e., naive ideas) than males for familiar taxa. Together these results indicate that gender achievement differences for this

  16. Determination of validity and reliability of performance assessments tasks developed for selected topics in high school chemistry

    Science.gov (United States)

    Zichittella, Gail Eberhardt

    The primary purpose of this study was to validate performance assessments, which can be used as teaching and assessment instruments in high school science classrooms. This study evaluated the classroom usability of these performance instruments and establishes the interrater reliability of the scoring rubrics when used by classroom teachers. The assessment instruments were designed to represent two levels of scientific inquiry. The high level of inquiry tasks are relatively unstructured in terms of student directions; the low inquiry tasks provided more structure for the student. The tasks cover two content topics studied in chemistry (scientific observation and density). Students from a variety of Western New York school districts who were enrolled in chemistry classes and other science courses were involved in completion of the tasks at the two levels of inquiry. The chemistry students completed the NYS Regents Examination in Chemistry. Their classroom teachers were interviewed and completed a questionnaire to aid in the establishment their epistemological view on the inclusion of inquiry based learning in the science classroom. Data showed that the performance assessment tasks were reliable, valid and helpful for obtaining a more complete picture of the students' scientific understanding. The teacher participants reported no difficulty with the usability of the task in the high school chemistry setting. Collected data gave no evidence of gender bias with reference to the performance tasks or the NYS Regents Chemistry Examination. Additionally, it was shown that the instructors' classroom practices do have an effect upon the students' achievement on the performance tasks and the NYS Regents examination. Data also showed that achievement on the performance tasks was influenced by the number of years of science instruction students had received.

  17. Planning, Implementing, and Assessing an Authentic Performance Task in Middle Grades Classrooms

    Science.gov (United States)

    Barnes, Nicole C.; Urbankowski, Daniel

    2014-01-01

    As young adolescents, middle grades students experience a wide variety of changes related to their cognitive capabilities, social and emotional well-being, and use of self-regulation strategies. Authentic performance tasks challenge students to apply their knowledge and skills to realistic problems to create products or performances--consistent…

  18. Risk assessment of maintenance operations: the analysis of performing task and accident mechanism.

    Science.gov (United States)

    Carrillo-Castrillo, Jesús A; Rubio-Romero, Juan Carlos; Guadix, Jose; Onieva, Luis

    2015-01-01

    Maintenance operations cover a great number of occupations. Most small and medium-sized enterprises lack the appropriate information to conduct risk assessments of maintenance operations. The objective of this research is to provide a method based on the concepts of task and accident mechanisms for an initial risk assessment by taking into consideration the prevalence and severity of the maintenance accidents reported. Data were gathered from 11,190 reported accidents in maintenance operations in the manufacturing sector of Andalusia from 2003 to 2012. By using a semi-quantitative methodology, likelihood and severity were evaluated based on the actual distribution of accident mechanisms in each of the tasks. Accident mechanisms and tasks were identified by using those variables included in the European Statistics of Accidents at Work methodology. As main results, the estimated risk of the most frequent accident mechanisms identified for each of the analysed tasks is low and the only accident mechanisms with medium risk are accidents when lifting or pushing with physical stress on the musculoskeletal system in tasks involving carrying, and impacts against objects after slipping or stumbling for tasks involving movements. The prioritisation of public preventive actions for the accident mechanisms with a higher estimated risk is highly recommended.

  19. Performance-Based Task Assessment of Higher-Order Proficiencies in Redesigned STEM High Schools

    Science.gov (United States)

    Ernst, Jeremy V.; Glennie, Elizabeth; Li, Songze

    2017-01-01

    This study explored student abilities in applying conceptual knowledge when presented with structured performance tasks. Specifically, the study gauged proficiency in higher-order applications of students enrolled in earth and environmental science or biology. The student sample was drawn from a Redesigned STEM high school model where a tested…

  20. Self-Reported Versus Performance-Based Assessments of a Simple Mobility Task Among Older Adults in the Emergency Department.

    Science.gov (United States)

    Roedersheimer, Kyle M; Pereira, Greg F; Jones, Christopher W; Braz, Valerie A; Mangipudi, Sowmya A; Platts-Mills, Timothy F

    2016-02-01

    Accurate information about the mobility of independently living older adults is essential in determining whether they may be safely discharged home from the emergency department (ED). We assess the accuracy of self-reported ability to complete a simple mobility task among older ED patients. This was a cross-sectional study of cognitively intact patients aged 65 years and older who were neither nursing home residents nor critically ill, conducted in 2 academic EDs. Consenting participants were asked whether they could get out of bed, walk 10 feet, turn around, and get back in bed without assistance, and if not, whether they could perform this task with a cane, walker, or assistance. Each participant was then asked to perform the task and was provided with a mobility device or assistance as needed. Of 272 patients who met eligibility criteria and answered the physical task question, 161 (59%) said they could do the task unassisted, 45 (17%) said they could do it with a cane or walker, 21 (8%) said they could do it with assistance, and 45 (17%) said they would be unable to do it even with assistance. Among those who said they could do the task either with or without assistance and who were subsequently willing to attempt the task (N=172), discrepancies between self-reported ability and actual performance were common. Of those who said they could perform the task without assistance, 12% required some assistance or were unable to complete the task. Of those who said they could perform the task with a cane or walker, 48% required either assistance or were unable to perform the task. Of those who said they could perform the task with assistance, 24% were unable to perform the task even with assistance. In this sample of older adults receiving care in the ED, the accuracy of their self-reported ability to perform a simple mobility task was poor, particularly for those who reported some need for assistance. For older adults being considered for discharge who report a need

  1. 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.

  2. A comparative analysis of multiple-choice and student performance-task assessment in the high school biology classroom

    Science.gov (United States)

    Cushing, Patrick Ryan

    This study compared the performance of high school students on laboratory assessments. Thirty-four high school students who were enrolled in the second semester of a regular biology class or had completed the biology course the previous semester participated in this study. They were randomly assigned to examinations of two formats, performance-task and traditional multiple-choice, from two content areas, using a compound light microscope and diffusion. Students were directed to think-aloud as they performed the assessments. Additional verbal data were obtained during interviews following the assessment. The tape-recorded narrative data were analyzed for type and diversity of knowledge and skill categories, and percentage of in-depth processing demonstrated. While overall mean scores on the assessments were low, elicited statements provided additional insight into student cognition. Results indicated that a greater diversity of knowledge and skill categories was elicited by the two microscope assessments and by the two performance-task assessments. In addition, statements demonstrating in-depth processing were coded most frequently in narratives elicited during clinical interviews following the diffusion performance-task assessment. This study calls for individual teachers to design authentic assessment practices and apply them to daily classroom routines. Authentic assessment should be an integral part of the learning process and not merely an end result. In addition, teachers are encouraged to explicitly identify and model, through think-aloud methods, desired cognitive behaviors in the classroom.

  3. Physical Ability-Task Performance Models: Assessing the Risk of Omitted Variable Bias

    Science.gov (United States)

    2008-09-15

    association was evaluated in a study of simulated job performance in men and women. The study measured four major abilities, Static Strength (SS), Dynamic...ability- performance interface for physical tasks. Methods Sample Participants were active-duty naval personnel (64 men , 38 women) between ages 20...bench with feet flat on the floor. Position was adjusted so the bar was between the shoulder and nipple line. Handles were gripped at a comfortable

  4. IEA-SHC Task 27: Environmental performance assessment of glazing and windows - context, overview, main concerns

    Energy Technology Data Exchange (ETDEWEB)

    Chevalier, J.L. [Centre Scientifique et Technique du Batiment, Sustainable Development Dept., Saint-Martin D' Heres (France); Krogh, H. [Danish Building and Urban Research, Energy and Indoor Climate Div., Hoersholm (Denmark); Tarantini, Mario [The Italian National Agency for New Technology, Energy and the Environment, Bologna (Italy)

    2006-07-01

    While all industrial sectors are integrating the environment concern into their culture and strategy, actors of the construction field seem to be torn between motivation and suspicion in front of this new topic. In most countries, the economic situation of the passed years for building was not suitable for investing in new long-term approaches, and the strong particularities of the building world appear as many complicating elements for introducing new concepts easily. But now the awareness for a sustainable development of all human activities is also growing in our sector, and it is time to take benefit of some favourable habits like the use of multi-criteria analysis: beyond performances, suitability for use, and durability, environmental quality criteria will just widen the actual scope of the technical assessment of building products. The first question is a double one : Who will use environmental criteria related to the building products, and for which purpose? Because actors in the field are many, we will have several distinct answers, which may call for different tools. In other industrial sectors, two approaches have been experimented: the Life Cycle Analysis (LCA) and the environmental labelling. Between LCA and green labels, several relevant tools are in development for the building products, each of them adapted to specific users and objectives, and most often of limited use in other contexts. A short review of the studies already performed on the environmental quality of glazing and windows revealed quite a small amount of available matter, and justifies the work undertaken within the programme of IEA/SHCP/Task 27, which will be presented in the third part of this paper. (au)

  5. Video-task assessment of learning and memory in Macaques (Macaca mulatta) - Effects of stimulus movement on performance

    Science.gov (United States)

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

    1989-01-01

    Effects of stimulus movement on learning, transfer, matching, and short-term memory performance were assessed with 2 monkeys using a video-task paradigm in which the animals responded to computer-generated images by manipulating a joystick. Performance on tests of learning set, transfer index, matching to sample, and delayed matching to sample in the video-task paradigm was comparable to that obtained in previous investigations using the Wisconsin General Testing Apparatus. Additionally, learning, transfer, and matching were reliably and significantly better when the stimuli or discriminanda moved than when the stimuli were stationary. External manipulations such as stimulus movement may increase attention to the demands of a task, which in turn should increase the efficiency of learning. These findings have implications for the investigation of learning in other populations, as well as for the application of the video-task paradigm to comparative study.

  6. Assessing the influence of a passive, upper extremity exoskeletal vest for tasks requiring arm elevation: Part I - "Expected" effects on discomfort, shoulder muscle activity, and work task performance.

    Science.gov (United States)

    Kim, Sunwook; Nussbaum, Maury A; Mokhlespour Esfahani, Mohammad Iman; Alemi, Mohammad Mehdi; Alabdulkarim, Saad; Rashedi, Ehsan

    2018-03-07

    Use of exoskeletal vests (designed to support overhead work) can be an effective intervention approach for tasks involving arm elevation, yet little is known on the potential beneficial impacts of their use on physical demands and task performance. This laboratory study (n = 12) evaluated the effects of a prototype exoskeletal vest during simulated repetitive overhead drilling and light assembly tasks. Anticipated or expected benefits were assessed, in terms of perceived discomfort, shoulder muscle activity, and task performance. Using the exoskeletal vest did not substantially influence perceived discomfort, but did decrease normalized shoulder muscle activity levels (e.g., ≤ 45% reduction in peak activity). Drilling task completion time decreased by nearly 20% with the vest, but the number of errors increased. Overall, exoskeletal vest use has the potential to be a new intervention for work requiring arm elevation; however, additional investigations are needed regarding potential unexpected or adverse influences (see Part II). Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Child abuse and performance task assessments of executive functions in boys.

    Science.gov (United States)

    Mezzacappa, E; Kindlon, D; Earls, F

    2001-11-01

    We examined executive functions using performance tasks in 126 boys aged 6 to 16 years. who attended public schools and therapeutic schools for children with emotional and behavioral problems. Children were further grouped based on the presence or absence of substantiated abuse histories. Based on their abuse histories and schools of origin, children were classified as Therapeutic, Abused (TA, N = 25). Therapeutic, Nonabused (TN, N = 52), and Public School (PS, N = 48). Controlling IQ and medication status, we compared children in the three groups on teacher ratings of behavior, on experimenter observations of behavior during testing, and on performance tasks challenging the capacities to inhibit an act in progress, and to passively avoid responses associated with adverse consequences. We examined mean group differences in symptoms, behaviors, and task performance, as well as differential age-dependent changes in these dimensions. Independent of abuse history, therapeutic school children demonstrated comparable levels of internalizing and externalizing symptoms, and comparable levels of redirections to task during testing-sessions, that were significantly higher than those of the public school children. Both groups of therapeutic school children also showed comparable overall performance on the capacities to inhibit an act in progress, and to passively avoid responses associated with adverse consequences that were poorer than the performance of children from the public school. Children with histories of substantiated abuse showed diminished improvement with increasing age in the capacity to passively avoid responses associated with adverse consequences when compared not only to the public school children, but also to the children from the therapeutic schools without histories of abuse. Our findings complement reports of behavioral observations of abused children, and reports associating child abuse with altered cognitive development in other areas of competence

  8. Task performance fraud risk assessment on forensic accountant and auditor knowledge and mindset in Nigerian public sector

    Directory of Open Access Journals (Sweden)

    Oluwatoyin Muse Johnson Popoola

    2014-10-01

    Full Text Available This paper discusses task performance fraud risk assessment and forensic accountant and auditor knowledge and mindset in the Nigerian public sector. The aim of the study is to examine the fraud risk assessment in the Nigerian public sector through the efficient utilisation of forensic accountant and auditor knowledge and mindset. The effect will enhance the corporate governance and accountability practices among public sector accountants and auditors in Nigeria

  9. Assessing language and visuospatial functions with one task: a "dual use" approach to performing fMRI in children.

    Science.gov (United States)

    Ebner, Kathina; Lidzba, Karen; Hauser, Till-Karsten; Wilke, Marko

    2011-10-01

    In order to increase the rate of successful functional MR studies in children it is helpful to shorten the time spent in the scanner. To this effect, assessing two cognitive functions with one task seems to be a promising approach. The hypothesis of this study was that the control condition of an established language task (vowel identification task, VIT) requires visuospatial processing and that the control condition (VIT(CC)) therefore may also be applicable to localize visuospatial functions. As a reference task, a visual search task (VST, previously established for use in children) was employed. To test this hypothesis, 43 children (19 f, 24 m; 12.0±2.6, range 7.9 to 17.8 years) were recruited and scanned using both tasks. Second-level random effects group analyses showed activation of left inferior-frontal cortex in the active condition of the VIT, as in previous studies. Additionally, analysis of the VIT(CC) demonstrated activation in right-dominant superior parietal and high-frontal brain regions, classically associated with visuospatial functions; activation seen in the VST was similar with a substantial overlap. However, lateralization in the parietal lobe was significantly more bilateral in the VST than in the VIT(CC). This suggests that the VIT can not only be applied to assess language functions (using the active>control contrast), but also that the control>active condition is useful for assessing visuospatial functions. Future task design may benefit from such a "dual use" approach to performing fMRI not only, but also particularly in children. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. A Population of Assessment Tasks

    Science.gov (United States)

    Daro, Phil; Burkhardt, Hugh

    2012-01-01

    We propose the development of a "population" of high-quality assessment tasks that cover the performance goals set out in the "Common Core State Standards for Mathematics." The population will be published. Tests are drawn from this population as a structured random sample guided by a "balancing algorithm."

  11. The assessment of Attention Deficit Hyperactivity Disorder in children using continous performance tasks in virtual environments

    OpenAIRE

    Gutiérrez Maldonado, José; Letosa Porta, A.; Rus Calafell, M.; Peñaloza Salazar, C.

    2009-01-01

    The assessment of Attention-Deficit/Hyperactivity Disorder (ADHD) involves the use of different instruments, and one of the most frequently used is the Continuous Performance Test (CPT). Virtual reality allows for the achieving of the presentation of stimuli with high levels of control. In addition, it facilitates the presentation of distracters with a high level of resemblance to elements which in fact can be found in the real world by placing them in a similar context. Thus, it is possible ...

  12. Impaired performance from brief social isolation of rhesus monkeys (Macaca mulatta) - A multiple video-task assessment

    Science.gov (United States)

    Washburn, David A.; Rumbaugh, Duane M.

    1991-01-01

    Social isolation has been demonstrated to produce profound and lasting psychological effects in young primates. In the present investigation, two adult rhesus monkeys (Macaca mulatta) were isolated from one another for up to 6 days and tested on 7 video tasks designed to assess psychomotor and cognitive functioning. Both the number and quality (i.e., speed and accuracy) of responses were significantly compromised in the social isolation condition relative to levels in which the animals were tested together. It is argued that adult rhesus are susceptible to performance disruption by even relatively brief social isolation, and that these effects can best be assessed by a battery of complex and sensitive measures.

  13. Performance on naturalistic virtual reality tasks depends on global cognitive functioning as assessed via traditional neurocognitive tests.

    Science.gov (United States)

    Oliveira, Jorge; Gamito, Pedro; Alghazzawi, Daniyal M; Fardoun, Habib M; Rosa, Pedro J; Sousa, Tatiana; Picareli, Luís Felipe; Morais, Diogo; Lopes, Paulo

    2017-08-14

    This investigation sought to understand whether performance in naturalistic virtual reality tasks for cognitive assessment relates to the cognitive domains that are supposed to be measured. The Shoe Closet Test (SCT) was developed based on a simple visual search task involving attention skills, in which participants have to match each pair of shoes with the colors of the compartments in a virtual shoe closet. The interaction within the virtual environment was made using the Microsoft Kinect. The measures consisted of concurrent paper-and-pencil neurocognitive tests for global cognitive functioning, executive functions, attention, psychomotor ability, and the outcomes of the SCT. The results showed that the SCT correlated with global cognitive performance as measured with the Montreal Cognitive Assessment (MoCA). The SCT explained one third of the total variance of this test and revealed good sensitivity and specificity in discriminating scores below one standard deviation in this screening tool. These findings suggest that performance of such functional tasks involves a broad range of cognitive processes that are associated with global cognitive functioning and that may be difficult to isolate through paper-and-pencil neurocognitive tests.

  14. 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....

  15. 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...

  16. Understanding Learner Strengths and Weaknesses: Assessing Performance on an Integrated Writing Task

    Science.gov (United States)

    Sawaki, Yasuyo; Quinlan, Thomas; Lee, Yong-Won

    2013-01-01

    The present study examined the factor structures across features of 446 examinees' responses to a writing task that integrates reading and listening modalities as well as reading and listening comprehension items of the TOEFL iBT[R] (Internet-based test). Both human and automated scores obtained for the integrated essays were utilized. Based on a…

  17. Initial experience using a robotic-driven laparoscopic needle holder with ergonomic handle: assessment of surgeons' task performance and ergonomics.

    Science.gov (United States)

    Sánchez-Margallo, Juan A; Sánchez-Margallo, Francisco M

    2017-12-01

    The objective of this study is to assess the surgeons' performance and ergonomics during the use of a robotic-driven needle holder in laparoscopic suturing tasks. Six right-handed laparoscopic surgeons with different levels of experience took part in this study. Participants performed a set of three different intracorporeal suturing tasks organized in ten trials during a period of five weeks. Surgeons used both conventional (Conv) and robotic (Rob) laparoscopic needle holders. Precision using the surgical needle, quality of the intracorporeal suturing performance, execution time and leakage pressure for the urethrovesical anastomosis, as well as the ergonomics of the surgeon's hand posture, were analyzed during the first, fifth and last trials. No statistically significant differences in precision and quality of suturing performance were obtained between both groups of instruments. Surgeons required more time using the robotic instrument than using the conventional needle holder to perform the urethrovesical anastomosis, but execution time was significantly reduced after training ([Formula: see text] 0.05). There were no differences in leakage pressure for the anastomoses carried out by both instruments. After training, novice surgeons significantly improved the ergonomics of the wrist ([Formula: see text] 0.05) and index finger (Conv: 36.381[Formula: see text], Rob: 30.389[Formula: see text]; p = 0.024) when using the robotic instrument compared to the conventional needle holder. Results have shown that, although both instruments offer similar technical performance, the robotic-driven instrument results in better ergonomics for the surgeon's hand posture compared to the use of a conventional laparoscopic needle holder in intracorporeal suturing.

  18. Comparative assessment of surgeons' task performance and surgical ergonomics associated with conventional and modified flank positions: a simulation study.

    Science.gov (United States)

    Fan, Yu; Kong, Gaiqing; Meng, Yisen; Tan, Shutao; Wei, Kunlin; Zhang, Qian; Jin, Jie

    2014-11-01

    Flank position is extensively used in retroperitoneoscopic urological practice. Most surgeons follow the patients' position in open approaches. However, surgical ergonomics of the conventional position in the retroperitoneoscopic surgery is poor. We introduce a modified position and evaluated task performance and surgical ergonomics of both positions with simulated surgical tasks. Twenty-one novice surgeons were recruited to perform four tasks: bead transfer, ring transfer, continuous suturing, and cutting a circle. The conventional position was simulated by setting an endo-surgical simulator parallel to the long axis of a surgical desk. The modified position was simulated by rotating the simulator 30° with respect to the long axis of the desk. The outcome measurements include task performance measures, kinematic measures for body alignment, surface electromyography, relative loading between feet, and subjective ratings of fatigue. We observed significant improvements in both task performance and surgical ergonomics parameters under the modified position. For all four tasks, subjects finished tasks faster with higher accuracy (p ergonomics part: (1) The angle between the upper body and the head was decreased by 7.4 ± 1.7°; (2) The EMG amplitude collected from shoulders and left lumber was significantly lower (p ergonomics. With a simulated surgery, we demonstrated that our modified position could significantly improve task performance and surgical ergonomics. Further studies are still warranted to validate these benefits for both patients and surgeons.

  19. The Assessment of Military Multitasking Performance: Validation of a Dual-Task and Multitask Protocol

    Science.gov (United States)

    2015-11-01

    preliminary validity of the Walking and Remembering Test. Journal of geriatric physical therapy . 2009;32(1):2-9. 23. Mancini M, Salarian A, Carlson-Kuhta P...MacMillan), American Physical Therapy Association (APTA) 2014 Annual conference, Charlotte, NC 88 August 18-21, 2014 (paper) A novel dual...Multitasking Performance for Mild TBI. Federal Section, American Physical Therapy Association’s Combined Section Meeting, (Weightman, Scherer, McCulloch

  20. An Assessment of Instant Messaging Interruptions on Knowledge Workers' Task Performance in E-Learning-Based Training

    Science.gov (United States)

    Mansi, Gary R.

    2011-01-01

    The modern workplace environment is filled with interruptions due to the necessity of coworkers to communicate with each other. Studies have revealed that interruptions can disrupt the ability of a knowledge worker to concentrate on a task, which can impact task performance (TP). Communication interruptions are due, in part, to the unavoidable…

  1. Predictive performance models and multiple task performance

    Science.gov (United States)

    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.

  2. 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....

  3. [Determinants of task preferences when performance is indicative of individual characteristics: self-assessment motivation and self-verification motivation].

    Science.gov (United States)

    Numazaki, M; Kudo, E

    1995-04-01

    The present study was conducted to examine determinants of information-gathering behavior with regard to one's own characteristics. Four tasks with different self-congruent and incongruent diagnosticity were presented to subjects. As self-assessment theory predicted, high diagnostic tasks were preferred to low tasks. And as self-verification theory predicted, self-congruent diagnosticity had a stronger effect on task preference than self-incongruent diagnosticity. In addition, subjects who perceived the relevant characteristics important inclined to choose self-assessment behavior more than who did not. Also, subjects who were certain of their self-concept inclined to choose self-verification behavior more than who were not. These results suggest that both self-assessment and self-verification motivations play important roles in information-gathering behavior regarding one's characteristics, and strength of the motivations is determined by the importance of relevant characteristics or the certainty of self-concept.

  4. 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…

  5. 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.

  6. Comparing Cognitive Models of Domain Mastery and Task Performance in Algebra: Validity Evidence for a State Assessment

    Science.gov (United States)

    Warner, Zachary B.

    2013-01-01

    This study compared an expert-based cognitive model of domain mastery with student-based cognitive models of task performance for Integrated Algebra. Interpretations of student test results are limited by experts' hypotheses of how students interact with the items. In reality, the cognitive processes that students use to solve each item may be…

  7. Association between central obesity and executive function as assessed by stroop task performance: A functional near-infrared spectroscopy study

    Directory of Open Access Journals (Sweden)

    Zhangyan Deng

    2018-01-01

    Full Text Available Recent studies have suggested a link between executive function (EF and obesity. Studies often adopt body mass index (BMI, which reflects the distribution of subcutaneous fat, as the sole marker of obesity; however, BMI is inappropriate to distinguish central obesity, which indicates the centralized distribution of visceral fat. Visceral fat compared with subcutaneous fat represents greater relative lipid turnover and may increase the risk of cognitive decline in older adults. However, the relationship between EF and central obesity is largely unknown, particularly in young adults. Therefore, we used waist circumference (WC as a marker of central obesity and investigated different sensitivities between BMI and WC in the brain function. A total of 26 healthy young adults (aged 18–25 years; 42% female underwent functional near-infrared spectroscopy assessments. EF was assessed using the Stroop task, which is a classical measurement of EF. A significant Stroop effect was observed in the behavioral and hemodynamic data. In addition, we observed that behavioral interference on the Stroop task varied much more in subjects with higher BMI and WC than those subjects with lower. Elevated BMI and WC were associated with a decreased hemodynamic response during the Stroop task specifically in the prefrontal cortex (PFC. Compared to BMI, WC was more closely connected with inhibitory control and revealed right lateralized PFC activation. Our findings suggest that WC is a reliable indicator of brain function in young adults and propose a relationship between EF and central obesity.

  8. Assessment of the dose reduction potential of a model-based iterative reconstruction algorithm using a task-based performance metrology

    International Nuclear Information System (INIS)

    Samei, Ehsan; Richard, Samuel

    2015-01-01

    Purpose: Different computed tomography (CT) reconstruction techniques offer different image quality attributes of resolution and noise, challenging the ability to compare their dose reduction potential against each other. The purpose of this study was to evaluate and compare the task-based imaging performance of CT systems to enable the assessment of the dose performance of a model-based iterative reconstruction (MBIR) to that of an adaptive statistical iterative reconstruction (ASIR) and a filtered back projection (FBP) technique. Methods: The ACR CT phantom (model 464) was imaged across a wide range of mA setting on a 64-slice CT scanner (GE Discovery CT750 HD, Waukesha, WI). Based on previous work, the resolution was evaluated in terms of a task-based modulation transfer function (MTF) using a circular-edge technique and images from the contrast inserts located in the ACR phantom. Noise performance was assessed in terms of the noise-power spectrum (NPS) measured from the uniform section of the phantom. The task-based MTF and NPS were combined with a task function to yield a task-based estimate of imaging performance, the detectability index (d′). The detectability index was computed as a function of dose for two imaging tasks corresponding to the detection of a relatively small and a relatively large feature (1.5 and 25 mm, respectively). The performance of MBIR in terms of the d′ was compared with that of ASIR and FBP to assess its dose reduction potential. Results: Results indicated that MBIR exhibits a variability spatial resolution with respect to object contrast and noise while significantly reducing image noise. The NPS measurements for MBIR indicated a noise texture with a low-pass quality compared to the typical midpass noise found in FBP-based CT images. At comparable dose, the d′ for MBIR was higher than those of FBP and ASIR by at least 61% and 19% for the small feature and the large feature tasks, respectively. Compared to FBP and ASIR, MBIR

  9. Assessment of the dose reduction potential of a model-based iterative reconstruction algorithm using a task-based performance metrology

    Energy Technology Data Exchange (ETDEWEB)

    Samei, Ehsan, E-mail: samei@duke.edu [Carl E. Ravin Advanced Imaging Laboratories, Clinical Imaging Physics Group, Departments of Radiology, Physics, Biomedical Engineering, and Electrical and Computer Engineering, Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 (United States); Richard, Samuel [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, Durham, North Carolina 27710 (United States)

    2015-01-15

    Purpose: Different computed tomography (CT) reconstruction techniques offer different image quality attributes of resolution and noise, challenging the ability to compare their dose reduction potential against each other. The purpose of this study was to evaluate and compare the task-based imaging performance of CT systems to enable the assessment of the dose performance of a model-based iterative reconstruction (MBIR) to that of an adaptive statistical iterative reconstruction (ASIR) and a filtered back projection (FBP) technique. Methods: The ACR CT phantom (model 464) was imaged across a wide range of mA setting on a 64-slice CT scanner (GE Discovery CT750 HD, Waukesha, WI). Based on previous work, the resolution was evaluated in terms of a task-based modulation transfer function (MTF) using a circular-edge technique and images from the contrast inserts located in the ACR phantom. Noise performance was assessed in terms of the noise-power spectrum (NPS) measured from the uniform section of the phantom. The task-based MTF and NPS were combined with a task function to yield a task-based estimate of imaging performance, the detectability index (d′). The detectability index was computed as a function of dose for two imaging tasks corresponding to the detection of a relatively small and a relatively large feature (1.5 and 25 mm, respectively). The performance of MBIR in terms of the d′ was compared with that of ASIR and FBP to assess its dose reduction potential. Results: Results indicated that MBIR exhibits a variability spatial resolution with respect to object contrast and noise while significantly reducing image noise. The NPS measurements for MBIR indicated a noise texture with a low-pass quality compared to the typical midpass noise found in FBP-based CT images. At comparable dose, the d′ for MBIR was higher than those of FBP and ASIR by at least 61% and 19% for the small feature and the large feature tasks, respectively. Compared to FBP and ASIR, MBIR

  10. Development of a taxonomy of performance influencing factors for human reliability assessment of accident management tasks and its application

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Whan; Jung, Won Dae; Kang, Dae Il; Ha, Jae Joo

    1999-06-01

    In this study, a new PIF taxonomy for HRA of the tasks during emergency operation and accident management situations. We collected the existing PIF taxonomies as many as possible. Then, we analyzed the trend in the selection of PIFs, the frequency of use between PIFs in HRA methods, and the level of definition of PIFs, in order to reflect these characteristics into the development of a new PIF taxonomy. Next, we analyzed the principal task context during accident management to draw the context specific PIFs. Afterwards, we established several criteria for the selection of the appropriate PIFs for HRA under emergency operation and accident management situations. Finally, the final PIF taxonomy containing the subitems for assessing each PIF was constructed based on the results of the previous steps and the selection criteria. The final result ofthis study is the new PIF taxonomy for HRA of the tasks during emergency operation and accident management situations. The selected 11 PIFs in the study are as follows: training and experience, availability and quality of information, status and trend of critical parameters, status of safety system/component, time pressure, working environment features, team cooperation and communication, plant policy and safety culture. (author). 35 refs., 23 tabs.

  11. Development of a taxonomy of performance influencing factors for human reliability assessment of accident management tasks and its application

    International Nuclear Information System (INIS)

    Kim, Jae Whan; Jung, Won Dae; Kang, Dae Il; Ha, Jae Joo

    1999-06-01

    In this study, a new PIF taxonomy for HRA of the tasks during emergency operation and accident management situations. We collected the existing PIF taxonomies as many as possible. Then, we analyzed the trend in the selection of PIFs, the frequency of use between PIFs in HRA methods, and the level of definition of PIFs, in order to reflect these characteristics into the development of a new PIF taxonomy. Next, we analyzed the principal task context during accident management to draw the context specific PIFs. Afterwards, we established several criteria for the selection of the appropriate PIFs for HRA under emergency operation and accident management situations. Finally, the final PIF taxonomy containing the subitems for assessing each PIF was constructed based on the results of the previous steps and the selection criteria. The final result of this study is the new PIF taxonomy for HRA of the tasks during emergency operation and accident management situations. The selected 11 PIFs in the study are as follows: training and experience, availability and quality of information, status and trend of critical parameters, status of safety system/component, time pressure, working environment features, team cooperation and communication, plant policy and safety culture. (author). 35 refs., 23 tabs

  12. Short and longer duration effects of protective gloves on hand performance capabilities and subjective assessments in a screw-driving task.

    Science.gov (United States)

    Dianat, Iman; Haslegrave, Christine M; Stedmon, Alex W

    2010-12-01

    The study investigated short and longer duration effects of gloves on hand performance capabilities (muscle activity, dexterity, touch sensitivity, finger pinch and forearm torque strength) and subjective assessments of discomfort and ease of manipulation when performing a light assembly task. The independent variables were hand condition with four levels (wearing cotton, nylon or nitrile gloves as well as barehanded) and point of time within the 2 h duration of the task (with measurements taken at 0, 30, 60, 90 and 120 min). Participants worked with a screwdriver to fit two components together using screws. Wearing gloves significantly increased the muscle activity, pinch strength and discomfort but reduced the dexterity and touch sensitivity. There was also a significant effect of task time on the muscle activity, dexterity, forearm torque strength and touch sensitivity, which indicates that the duration of the task should be an important consideration in glove evaluation studies and in the selection of work gloves. STATEMENT OF RELEVANCE: It is important to evaluate the effects of gloves on hand performance capabilities in a working context so that job demands can be taken into account and the most appropriate type of glove be chosen for each task. This study gives recommendations regarding the evaluation and use of gloves for screw-driving tasks.

  13. Performance assessment

    International Nuclear Information System (INIS)

    Doe, T.

    1985-01-01

    The purpose of performance assessment is to show that the repository is expected to serve its stated function - disposing of radioactive waste safely both during operation and for the postclosure period. Performance assessment is a straightforward concept, but its application may be very complicated. The concept of performance assessment has been clarified by the Nuclear Regulatory Commission (NRC) in their Draft Generic Technical Position on Licensing Assessment Methodology for High-Level Waste Geologic Repositories (NRC, 1984). This document has gone a long way toward defining the criteria that the NRC will use to determine whether or not information from site characterization is adequate to meet the regulations of the Nuclear Regulatory Commission and the Environmental Protection Agency (EPA). A favorable determination is required for issuance of a construction authorization, which is the first major regulatory requirement for developing a working repository. It is, therefore, essential that a research program be developed that not only resolves the outstanding technical issues, but also does it in such a way that the results are clearly applicable to the formal performance assessment and licensing procedures. The definitions of performance assessment are reviewed and the current NRC thinking is summarized

  14. Initial evaluation of psychometric properties of a structured work task application for the Assessment of Work Performance in a constructed environment.

    Science.gov (United States)

    Karlsson, Elin A; Liedberg, Gunilla M; Sandqvist, Jan L

    2017-06-22

    The Swedish Social Insurance Administration has developed a new assessment tool for sickness insurance. This study is a part of the initial evaluation of the application, called the Assessment of Work Performance, Structured Activities, and focuses on evaluation of the psychometric properties of social validity, content validity, and utility. This was a qualitative study using semi-structured telephone interviews with occupational therapists. A convenience sample was used and participants who fulfilled inclusion criteria (n = 15) were interviewed. Data were analyzed using content analysis with a directed approach. The results indicate that the application provides valuable information and that it is socially valid. Assessors found work tasks suitable for a diverse group of clients and reported that clients accepted the assessments. Improvements were suggested, for example, expanding the application with more work tasks. The instrument has benefits; however, further development is desired. The use of a constructed environment in assessments may be a necessary option to supplement a real environment. But depending on organizational factors such as time and other resources, the participants had different opportunities to do so. Further evaluations regarding ecological validity are essential to ensure that assessments are fair and realistic when using constructed environments. Implications for rehabilitation This study indicates that assessment in a constructed environment can provide a secure and protected context for clients being assessed. Psychometric evaluations are a never-ending process and this assessment instrument needs further development. However, this initial evaluation provides guidance in development of the instrument but also what studies to give priority to. It is important to evaluate social validity in order to ensure that clients and assessors perceive assessment methods fair and meaningful. In this study, participants found the work tasks

  15. 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.

  16. 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

  17. 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.

  18. Continuous Performance Tasks: Not Just about Sustaining Attention

    Science.gov (United States)

    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…

  19. Using pliers in assembly work: short and long task duration effects of gloves on hand performance capabilities and subjective assessments of discomfort and ease of tool manipulation.

    Science.gov (United States)

    Dianat, Iman; Haslegrave, Christine M; Stedmon, Alex W

    2012-03-01

    The present study investigated the effects of wearing typical industrial gloves on hand performance capabilities (muscle activity, wrist posture, touch sensitivity, hand grip and forearm torque strength) and subjective assessments for an extended duration of performing a common assembly task, wire tying with pliers, which requires a combination of manipulation and force exertion. Three commercially available gloves (cotton, nylon and nitrile gloves) were tested and compared with a bare hand condition while participants performed the simulated assembly task for 2 h. The results showed that wearing gloves significantly increased the muscle activity, wrist deviation, and discomfort whilst reducing hand grip strength, forearm torque strength and touch sensitivity. The combined results showed that the length of time for which gloves are worn does affect hand performance capability and that gloves need to be evaluated in a realistic working context. The results are discussed in terms of selection of gloves for industrial assembly tasks involving pliers. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  20. 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.

  1. A Cognition Analysis of QUASAR's Mathematics Performance Assessment Tasks and Their Sensitivity to Measuring Changes in Middle School Students' Thinking and Reasoning.

    Science.gov (United States)

    Cai, Jinfa, And Others

    1996-01-01

    Presents a conceptual framework for analyzing students' mathematical understanding, reasoning, problem solving, and communication. Analyses of student responses indicated that the tasks appear to measure the complex thinking and reasoning processes that they were designed to assess. Concludes that the QUASAR assessment tasks can capture changes in…

  2. Pleasantness of Creative Tasks and Creative Performance

    Science.gov (United States)

    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.…

  3. Response of the medial temporal lobe network in amnestic mild cognitive impairment to therapeutic intervention assessed by fMRI and memory task performance

    Directory of Open Access Journals (Sweden)

    Arnold Bakker

    2015-01-01

    Full Text Available Studies of individuals with amnestic mild cognitive impairment (aMCI have detected hyperactivity in the hippocampus during task-related functional magnetic resonance imaging (fMRI. Such elevated activation has been localized to the hippocampal dentate gyrus/CA3 (DG/CA3 during performance of a task designed to detect the computational contributions of those hippocampal circuits to episodic memory. The current investigation was conducted to test the hypothesis that greater hippocampal activation in aMCI represents a dysfunctional shift in the normal computational balance of the DG/CA3 regions, augmenting CA3-driven pattern completion at the expense of pattern separation mediated by the dentate gyrus. We tested this hypothesis using an intervention based on animal research demonstrating a beneficial effect on cognition by reducing excess hippocampal neural activity with low doses of the atypical anti-epileptic levetiracetam. In a within-subject design we assessed the effects of levetiracetam in three cohorts of aMCI participants, each receiving a different dose of levetiracetam. Elevated activation in the DG/CA3 region, together with impaired task performance, was detected in each aMCI cohort relative to an aged control group. We observed significant improvement in memory task performance under drug treatment relative to placebo in the aMCI cohorts at the 62.5 and 125 mg BID doses of levetiracetam. Drug treatment in those cohorts increased accuracy dependent on pattern separation processes and reduced errors attributable to an over-riding effect of pattern completion while normalizing fMRI activation in the DG/CA3 and entorhinal cortex. Similar to findings in animal studies, higher dosing at 250 mg BID had no significant benefit on either task performance or fMRI activation. Consistent with predictions based on the computational functions of the DG/CA3 elucidated in basic animal research, these data support a dysfunctional encoding mechanism

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

    Science.gov (United States)

    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.

  5. The effect of breakfast versus no breakfast on brain activity in adolescents when performing cognitive tasks, as assessed by fMRI.

    Science.gov (United States)

    Fulford, Jonathan; Varley-Campbell, Joanna L; Williams, Craig A

    2016-01-01

    The study examined the feasibility of utilizing functional magnetic resonance imaging (fMRI) with a group of adolescent boys and girls to assess modifications in cognitive function, dependent upon the nutritional state of the participants. Twenty children aged 12-14 years completed two cognitive trials, in a randomized counterbalanced order, one under fasting condition, one after consuming breakfast, during which continuous fMRI data were acquired. Although no statistically significant (P > 0.05) improvement in task performance was determined, significantly higher activation was recorded in the frontal, premotor, and primary visual cortex areas in the breakfast trial relative to the fasting condition. Such a finding may have important implications in the examination of the role of diet, and specifically breakfast, in determining children's performance within the school environment.

  6. 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

  7. Response of Students to Statement Bank Feedback: The Impact of Assessment Literacy on Performances in Summative Tasks

    Science.gov (United States)

    Denton, Philip; McIlroy, David

    2018-01-01

    Efficiency gains arising from the use of electronic marking tools that allow tutors to select comments from a statement bank are well documented, but how students use this type of feedback remains under explored. Natural science students (N = 161) were emailed feedback reports on a spreadsheet assessment that included an invitation to reply placed…

  8. Trait Mindfulness and Cognitive Task Performance

    Directory of Open Access Journals (Sweden)

    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.

  9. Training Attentional Control Improves Cognitive and Motor Task Performance.

    Science.gov (United States)

    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.

  10. 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.

  11. Negative effects of chronic oral chlorpromazine and olanzapine treatment on the performance of tasks designed to assess spatial learning and working memory in rats.

    Science.gov (United States)

    Terry, A V; Warner, S E; Vandenhuerk, L; Pillai, A; Mahadik, S P; Zhang, G; Bartlett, M G

    2008-10-28

    chronic oral treatment with chlorpromazine or olanzapine can impair the performance of tasks designed to assess specific components of cognition that are affected in schizophrenia.

  12. SIMPLIFIED PREDICTIVE MODELS FOR CO₂ SEQUESTRATION PERFORMANCE ASSESSMENT RESEARCH TOPICAL REPORT ON TASK #3 STATISTICAL LEARNING BASED MODELS

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Srikanta; Schuetter, Jared

    2014-11-01

    We compare two approaches for building a statistical proxy model (metamodel) for CO₂ geologic sequestration from the results of full-physics compositional simulations. The first approach involves a classical Box-Behnken or Augmented Pairs experimental design with a quadratic polynomial response surface. The second approach used a space-filling maxmin Latin Hypercube sampling or maximum entropy design with the choice of five different meta-modeling techniques: quadratic polynomial, kriging with constant and quadratic trend terms, multivariate adaptive regression spline (MARS) and additivity and variance stabilization (AVAS). Simulations results for CO₂ injection into a reservoir-caprock system with 9 design variables (and 97 samples) were used to generate the data for developing the proxy models. The fitted models were validated with using an independent data set and a cross-validation approach for three different performance metrics: total storage efficiency, CO₂ plume radius and average reservoir pressure. The Box-Behnken–quadratic polynomial metamodel performed the best, followed closely by the maximin LHS–kriging metamodel.

  13. 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.

  14. 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

  15. Low-dose cone-beam CT via raw counts domain low-signal correction schemes: Performance assessment and task-based parameter optimization (Part II. Task-based parameter optimization).

    Science.gov (United States)

    Gomez-Cardona, Daniel; Hayes, John W; Zhang, Ran; Li, Ke; Cruz-Bastida, Juan Pablo; Chen, Guang-Hong

    2018-05-01

    and an anterior ROI, located further from the noise streaks region. Optimal results derived from the task-based detectability index metric were compared to other operating points in the parameter space with different noise and spatial resolution trade-offs. The optimal operating points determined through the d' metric depended on the interplay between the major spatial frequency components of each imaging task and the highly shift-variant and anisotropic noise and spatial resolution properties associated with each operating point in the LSC parameter space. This interplay influenced imaging performance the most when the major spatial frequency component of a given imaging task coincided with the direction of spatial resolution loss or with the dominant noise spatial frequency component; this was the case of imaging task II. The performance of imaging tasks I and III was influenced by this interplay in a smaller scale than imaging task II, since the major frequency component of task I was perpendicular to imaging task II, and because imaging task III did not have strong directional dependence. For both LSC methods, there was a strong dependence of the overall d' magnitude and shape of the contours on the spatial location within the phantom, particularly for imaging tasks II and III. The d' value obtained at the optimal operating point for each spatial location and imaging task was similar when comparing the LSC methods studied in this work. A local task-based detectability framework to optimize the selection of parameters for LSC methods was developed. The framework takes into account the potential shift-variant and anisotropic spatial resolution and noise properties to maximize the imaging performance of the CT system. Optimal parameters for a given LSC method depend strongly on the spatial location within the image object. © 2018 American Association of Physicists in Medicine.

  16. Training improves laparoscopic tasks performance and decreases operator workload.

    Science.gov (United States)

    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.

  17. Estimating functional cognition in older adults using observational assessments of task performance in complex everyday activities: A systematic review and evaluation of measurement properties.

    Science.gov (United States)

    Wesson, Jacqueline; Clemson, Lindy; Brodaty, Henry; Reppermund, Simone

    2016-09-01

    Functional cognition is a relatively new concept in assessment of older adults with mild cognitive impairment or dementia. Instruments need to be reliable and valid, hence we conducted a systematic review of observational assessments of task performance used to estimate functional cognition in this population. Two separate database searches were conducted: firstly to identify instruments; and secondly to identify studies reporting on the psychometric properties of the instruments. Studies were analysed using a published checklist and their quality reviewed according to specific published criteria. Clinical utility was reviewed and the information formulated into a best evidence synthesis. We found 21 instruments and included 58 studies reporting on measurement properties. The majority of studies were rated as being of fair methodological quality and the range of properties investigated was restricted. Most instruments had studies reporting on construct validity (hypothesis testing), none on content validity and there were few studies reporting on reliability. Overall the evidence on psychometric properties is lacking and there is an urgent need for further evaluation of instruments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Assessment for Learning Tasks and the Peer Assessment Process

    Science.gov (United States)

    Lauf, Lorraine; Dole, Shelley

    2010-01-01

    A program of Assessment for Learning (AfL) was implemented with 107 Year 12 students as part of their preparation for a major external test. Students completed extended mathematics tasks and selected student responses were used for peer assessment purposes. This paper reports on two of the AfL elements, namely task selection and peer assessment as…

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

    Science.gov (United States)

    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.

  20. Task force report on health effects assessment

    International Nuclear Information System (INIS)

    Anderson, C.; Hushon, J.

    1978-08-01

    From April to August, 1978 MITRE supported the Health Effects Assessment Task Force sponsored by the Office of the Assistant Secretary for the Environment at DOE. The findings of that Task Force are incorporated in this report and include a detailed definition of health effects assessment, a survey of the mandates for health effects assessments within DOE/EV, a review of current DOE-EV health effects assessment activities, an analysis of the constraints affecting the health effects assessment process and a discussion of the Task Force recommendations. Included as appendices are summaries of two workshops conducted by the Task Force to determine the state-of-the-art of health effects assessment and modeling and a review of risk assessment activities in other federal agencies. The primary recommendation of the panel was that an office be designated or created under the Office of the Assistant Secretary for the Environment to coordinate the Health Effects Risk Assessment effort covering up to 40 program and policy areas; a similar need was expressed for the environmental effects assessment area. 1 tab

  1. 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.

  2. 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.

  3. Effectiveness of ESL Students' Performance by Computational Assessment and Role of Reading Strategies in Courseware-Implemented Business Translation Tasks

    Science.gov (United States)

    Tsai, Shu-Chiao

    2017-01-01

    This study reports on investigating students' English translation performance and their use of reading strategies in an elective English writing course offered to senior students of English as a Foreign Language for 100 minutes per week for 12 weeks. A courseware-implemented instruction combined with a task-based learning approach was adopted.…

  4. 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...

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

    Science.gov (United States)

    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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Career Development, Collective Efficacy, and Individual Task Performance

    Science.gov (United States)

    Kellett, Janet B.; Humphrey, Ronald H.; Sleeth, Randall G.

    2009-01-01

    Purpose: The purpose of this paper is to test the hypothesis that perceived collective efficacy would mediate the effects of self-efficacy on individual task performance. Design/methodology/approach: An assessment center design with 147 participants in 49 three-person groups was used. Findings: It is found that for individuals working on an…

  11. 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.

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

    Science.gov (United States)

    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…

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. Shift Work and Cognitive Flexibility: Decomposing Task Performance.

    Science.gov (United States)

    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

  18. 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.

  19. 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.

  20. Energy performance assessment methodology

    Energy Technology Data Exchange (ETDEWEB)

    Platzer, W.J. [Fraunhofer Inst. for Solar Energy Systems, Freiburg (Germany)

    2006-01-15

    The energy performance of buildings are intimately connected to the energy performance of building envelopes. The better we understand the relation between the quality of the envelope and the energy consumption of the building, the better we can improve both. We have to consider not only heating but all service energies related to the human comfort in the building, such as cooling, ventilation, lighting as well. The complexity coming from this embracing approach is not to be underestimated. It is less and less possible to realted simple characteristic performance indicators of building envelopes (such as the U-value) to the overall energy performance. On the one hand much more paramters (e.g. light transmittance) come into the picture we have to assess the product quality in a multidimensional world. Secondly buildings more and more have to work on a narrow optimum: For an old, badly insulated building all solar gains are useful for a high-performance building with very good insulation and heat recovery systems in the ventilation overheating becomes more likely. Thus we have to control the solar gains, and sometimes we need high gains, sometimes low ones. And thirdly we see that the technology within the building and the user patterns and interactions as well influence the performance of a building envelope. The aim of this project within IEA Task27 was to improve our knowledge on the complex situation and also to give a principal approach how to assess the performance of the building envelope. The participants have contributed to this aim not pretending that we have reached the end. (au)

  1. 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.

  2. Task-based exposure assessment of nanoparticles in the workplace

    International Nuclear Information System (INIS)

    Ham, Seunghon; Yoon, Chungsik; Lee, Euiseung; Lee, Kiyoung; Park, Donguk; Chung, Eunkyo; Kim, Pilje; Lee, Byoungcheun

    2012-01-01

    Although task-based sampling is, theoretically, a plausible approach to the assessment of nanoparticle exposure, few studies using this type of sampling have been published. This study characterized and compared task-based nanoparticle exposure profiles for engineered nanoparticle manufacturing workplaces (ENMW) and workplaces that generated welding fumes containing incidental nanoparticles. Two ENMW and two welding workplaces were selected for exposure assessments. Real-time devices were utilized to characterize the concentration profiles and size distributions of airborne nanoparticles. Filter-based sampling was performed to measure time-weighted average (TWA) concentrations, and off-line analysis was performed using an electron microscope. Workplace tasks were recorded by researchers to determine the concentration profiles associated with particular tasks/events. This study demonstrated that exposure profiles differ greatly in terms of concentrations and size distributions according to the task performed. The size distributions recorded during tasks were different from both those recorded during periods with no activity and from the background. The airborne concentration profiles of the nanoparticles varied according to not only the type of workplace but also the concentration metrics. The concentrations measured by surface area and the number concentrations measured by condensation particle counter, particulate matter 1.0, and TWA mass concentrations all showed a similar pattern, whereas the number concentrations measured by scanning mobility particle sizer indicated that the welding fume concentrations at one of the welding workplaces were unexpectedly higher than were those at workplaces that were engineering nanoparticles. This study suggests that a task-based exposure assessment can provide useful information regarding the exposure profiles of nanoparticles and can therefore be used as an exposure assessment tool.

  3. 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.

  4. 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...

  5. Assessing visuospatial abilities in healthy aging: A novel visuomotor task

    Directory of Open Access Journals (Sweden)

    Natalie eDe Bruin

    2016-02-01

    Full Text Available This study examined the efficacy of a novel reaching-and-grasping task in determining visuospatial abilities across adulthood. The task required male and female young (18-25 years and older adults (60-82 years to replicate a series of complex models by locating and retrieving the appropriate building blocks from an array. The task allows visuospatial complexity to be manipulated independently from the visuomotor demands. Mental rotation and spatial visualisation abilities were assessed. The results showed that the time taken to complete the tasks increased with increased mental rotation complexity. Patterns of hand use were also influenced by the complexity of the models being constructed with right hand use being greater for the less complex models. In addition, although older adults consistently performed the visuomotor tasks slower than the younger adults, their performance was comparable when expressed as the percent change in task demands. This is suggestive that spatial abilities are preserved in older adults. Given the ecologically validity, the described task is an excellent candidate for investigating (1 developmental, (2 sex-based and (3 pathology-based differences in spatial abilities in the visuomotor domain.

  6. Task Performance induced Work Load in Nursing

    Directory of Open Access Journals (Sweden)

    Shirazeh Arghami

    2015-12-01

    Full Text Available Background & objective: High workload may lead to increase human errors, compromise quality and safety of care, and reduce the nurses’ quality of working life. The aim of this study is to determine the task-induced workload in nursing. Methods: This is a descriptive analytical study. All of 214 nurses of one of the educational hospital took part in. After obtaining informed consent from participants, data were collected based on NASA-TLX questionnaire and the desired level assumed less than 50%. Analysis of data was performed by descriptive statistics and Anova in SPSS software (version 11. 0 at significant level of 0.05. Results: The results showed that perceived mental pressure for nurses is more than other NASA-TLX subscales (P< .001. Also, the mean perceived workload was more than 50%. However, mean workload score of NASA-TLX showed significant correlation with age (P< .001, work experience (P< .001, shift work (P< .02, and department (P< .001. Conclusion: The results show that effective programs will be required to reduce the work load, and to enhance nurses' performance

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

    Science.gov (United States)

    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.

  8. 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

  9. 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.

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

    Science.gov (United States)

    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…

  11. Assessing executive functions in preschoolers using Shape School Task

    Directory of Open Access Journals (Sweden)

    Marta Nieto

    2016-09-01

    Full Text Available Over the last two decades, there has been a growing interest in the study of the development of executive functions in preschool children due to their relationship with different cognitive, psychological, social and academic domains. Early detection of individual differences in executive functioning can have major implications for basic and applied research. Consequently, there is a key need for assessment tools adapted to preschool skills: Shape School has been shown to be a suitable task for this purpose. Our study uses Shape School as the main task to analyze development of inhibition, task-switching and working memory in a sample of 304 preschoolers (age range 3.25-6.50 years. Additionally, we include cognitive tasks for the evaluation of verbal variables (vocabulary, word reasoning and short-term memory and performance variables (picture completion and symbol search, so as to analyze their relationship with executive functions. Our results show age-associated improvements in executive functions and the cognitive variables assessed. Furthermore, correlation analyses reveal positive relationships between executive functions and the other cognitive variables. More specifically, using structural equation modeling and including age direct and indirect effects, our results suggest that executive functions explain to a greater extent performance on verbal and performance tasks. These findings provide further information to support research that considers preschool age to be a crucial period for the development of executive functions and their relationship with other cognitive processes

  12. 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.

  13. Limitations in dual-task performance

    NARCIS (Netherlands)

    Pannebakker, Merel Mathilde

    2009-01-01

    In this thesis, the effect of information-processing overload on working-memory dependent information processing was examined using dual-task paradigms. The experiments described strengthen the importance of a functional explanation for dual-task limitations. First, it showed evidence for a unified

  14. 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

  15. 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

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

    Science.gov (United States)

    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.

  17. 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.

  18. Virtual Reality Stroop Task for neurocognitive assessment.

    Science.gov (United States)

    Parsons, Thomas D; Courtney, Christopher G; Arizmendi, Brian; Dawson, Michael

    2011-01-01

    Given the prevalence of traumatic brain injury (TBI), and the fact that many mild TBIs have no external marker of injury, there is a pressing need for innovative assessment technology. The demand for assessment that goes beyond traditional paper-and-pencil testing has resulted in the use of automated cognitive testing for increased precision and efficiency; and the use of virtual environment technology for enhanced ecological validity and increased function-based assessment. To address these issues, a Virtual Reality Stroop Task (VRST) that involves the subject being immersed in a virtual Humvee as Stroop stimuli appear on the windshield was developed. This study is an initial validation of the VRST as an assessment of neurocognitive functioning. When compared to the paper-and-pencil, as well as Automated Neuropsychological Assessment Metrics versions of the Stroop, the VRST appears to have enhanced capacity for providing an indication of a participant's reaction time and ability to inhibit a prepotent response while immersed in a military relevant simulation that presents psychophysiologically arousing high and low threat stimuli.

  19. Identifying the neural substrates of intrinsic motivation during task performance.

    Science.gov (United States)

    Lee, Woogul; Reeve, Johnmarshall

    2017-10-01

    Intrinsic motivation is the inherent tendency to seek out novelty and challenge, to explore and investigate, and to stretch and extend one's capacities. When people imagine performing intrinsically motivating tasks, they show heightened anterior insular cortex (AIC) activity. To fully explain the neural system of intrinsic motivation, however, requires assessing neural activity while people actually perform intrinsically motivating tasks (i.e., while answering curiosity-inducing questions or solving competence-enabling anagrams). Using event-related functional magnetic resonance imaging, we found that the neural system of intrinsic motivation involves not only AIC activity, but also striatum activity and, further, AIC-striatum functional interactions. These findings suggest that subjective feelings of intrinsic satisfaction (associated with AIC activations), reward processing (associated with striatum activations), and their interactions underlie the actual experience of intrinsic motivation. These neural findings are consistent with the conceptualization of intrinsic motivation as the pursuit and satisfaction of subjective feelings (interest and enjoyment) as intrinsic rewards.

  20. Limitations in dual-task performance

    OpenAIRE

    Pannebakker, Merel Mathilde

    2009-01-01

    In this thesis, the effect of information-processing overload on working-memory dependent information processing was examined using dual-task paradigms. The experiments described strengthen the importance of a functional explanation for dual-task limitations. First, it showed evidence for a unified coding medium (as put forward in the theory of event coding; Hommel, Müsseler, Aschersleben, & Prinz, 2001) in which features, operations and responses are available and can influence each other. A...

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

    Science.gov (United States)

    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…

  2. 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.

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

    Science.gov (United States)

    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.

  4. 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...

  5. Influence of malnutrition on cognitive development assessed by Piagetian tasks.

    Science.gov (United States)

    Agarwal, D K; Upadhyay, S K; Agarwal, K N

    1989-01-01

    Cognitive development of 1336 children (6-8 yr) was studied in relation to their nutritional status. Seven Piagetian tasks covering the mental process of a concrete operational period were given to each child to assess the cognitive development. Weschler intelligence scale for Indian Children was used to assess the IQ of each child. The percentage of malnourished children in stage I of development (preoperational) was significantly higher as that of wellnourished children. A higher percentage of children in the latter group was in stage III of development (concrete operation). In boys performance on all the tasks was influenced by undernutrition except for class inclusion. In girls this was true only for conservation of liquid, substance and ordinal relation. The results of the regression analysis showed that nutrition was the only factor weakly associated with the poor performance of the children in various tasks. Further, the effect of nutrition was more pronounced in conservation tasks indicating poor verbal reasoning and comprehension in malnourished children. Information was also collected regarding the parental education and occupation, socio-economic status, caste, economic sufficiency, psychosocial stimulation and home environment. However, these environmental factors did not influence the development of rural children. This might be due to the fact that the population in the present study did not vary much with regard to these variables.

  6. Rapid Authoring of Task Knowledge for Training and Performance Support

    National Research Council Canada - National Science Library

    Mohammed, John L; Sorensen, Barbara; Ong, James C; Li, Jian

    2005-01-01

    .... These systems use hierarchical, object-oriented task representations that enable rapid authoring by non-programmers while supporting sophisticated job aiding and student performance evaluation...

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  9. Process of performance assessment

    International Nuclear Information System (INIS)

    King, C.M.; Halford, D.K.

    1987-01-01

    Performance assessment is the process used to evaluate the environmental consequences of disposal of radioactive waste in the biosphere. An introductory review of the subject is presented. Emphasis is placed on the process of performance assessment from the standpoint of defining the process. Performance assessment, from evolving experience at DOE sites, has short-term and long-term subprograms, the components of which are discussed. The role of mathematical modeling in performance assessment is addressed including the pros and cons of current approaches. Finally, the system/site/technology issues as the focal point of this symposium are reviewed

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

    Science.gov (United States)

    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…

  11. The Effects of Performance-Based Assessment Criteria on Student Performance and Self-Assessment Skills

    Science.gov (United States)

    Fastre, Greet Mia Jos; van der Klink, Marcel R.; van Merrienboer, Jeroen J. G.

    2010-01-01

    This study investigated the effect of performance-based versus competence-based assessment criteria on task performance and self-assessment skills among 39 novice secondary vocational education students in the domain of nursing and care. In a performance-based assessment group students are provided with a preset list of performance-based…

  12. Computer task performance by subjects with Duchenne muscular dystrophy.

    Science.gov (United States)

    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.

  13. NRC performance assessment program

    International Nuclear Information System (INIS)

    Coplan, S.M.

    1986-01-01

    The U.S. Nuclear Regulatory Commission's (NRC) performance assessment program includes the development of guidance to the U.S. Department of Energy (DOE) on preparation of a license application and on conducting the studies to support a license application. The nature of the licensing requirements of 10 CFR Part 60 create a need for performance assessments by the DOE. The NRC and DOE staffs each have specific roles in assuring the adequacy of those assessments. Performance allocation is an approach for determining what testing and analysis will be needed during site characterization to assure that an adequate data base is available to support the necessary performance assessments. From the standpoint of establishing is implementable methodology, the most challenging performance assessment needed for licensing is the one that will be used to determine compliance with the U.S. Environmental Protection Agency's (EPA) containment requirement

  14. 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.

  15. 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.

  16. 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 ...

  17. 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.

  18. Chew on this: No support for facilitating effects of gum on spatial task performance.

    Science.gov (United States)

    Nader, Ingo W; Gittler, Georg; Waldherr, Karin; Pietschnig, Jakob

    2010-09-01

    To determine whether chewing of gum facilitates spatial task performance in healthy participants, two behavioral experiments were performed. In the first experiment, spatial task performance of 349 men and women preceding and after treatment administration (saccharated chewing gum, sugar-free chewing gum, no chewing gum) was assessed using effect modeling by means of Item Response Theory. In the second experiment, another 100 participants were either administered sugar-free chewing gum or no chewing gum during spatial task performance. Effects of gum in the second study were assessed by standard means of data analysis. Results indicated no significant effects of either chewing gum or sugar on spatial task performance in either experiment. Our findings are consistent with recent studies investigating the influences of chewing gum on various memory functions, extending them by another measure of cognitive ability. Thus, further doubt is cast on enhancing effects of chewing gum on cognitive task performance. Copyright 2010 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  1. 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

  2. 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

  3. Authentic tasks in higher education: Studying design principles for assessment

    NARCIS (Netherlands)

    van Keulen, H.; van den Berg, I.; Ramaekers, S.

    2006-01-01

    Students may benefit significantly from learning through authentic tasks. But how do we assess their learning outcomes, taking into account the specific characteristics of authentic tasks? In the second presentation of this symposium on design principles for authentic tasks we present and discuss

  4. 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.

  5. The Curvilinear Relationship between State Neuroticism and Momentary Task Performance

    Science.gov (United States)

    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

  6. 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...

  7. Teaching Software Developers to Perform UX Tasks

    DEFF Research Database (Denmark)

    Øvad, Tina; Bornoe, Nis; Larsen, Lars Bo

    2015-01-01

    . This is done via an action research study where the developers were provided with material concerning a modified AB usability test, by training them in performing this type of work, and by using their feedback to improve the method and the material. The overall result of the study is positive and it is found...... that by using the developers' feedback in the modification process, the method has truly become applicable within an agile, industrial setting. In combination with a guideline and template this has induced the developers to feel confident in independently performing this type of work....

  8. The impact of task characteristics on the performance of nursing teams

    Directory of Open Access Journals (Sweden)

    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.

  9. 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

  10. Investigating Conversational Dynamics: Interactive Alignment, Interpersonal Synergy, and Collective Task Performance

    Science.gov (United States)

    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 interlocutors, the synergy…

  11. 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…

  12. 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…

  13. When Mathematics and Statistics Collide in Assessment Tasks

    Science.gov (United States)

    Bargagliotti, Anna; Groth, Randall

    2016-01-01

    Because the disciplines of mathematics and statistics are naturally intertwined, designing assessment questions that disentangle mathematical and statistical reasoning can be challenging. We explore the writing statistics assessment tasks that take into consideration potential mathematical reasoning they may inadvertently activate.

  14. 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.

  15. Human Error Probabilites (HEPs) for generic tasks and Performance Shaping Factors (PSFs) selected for railway operations

    DEFF Research Database (Denmark)

    Thommesen, Jacob; Andersen, Henning Boje

    This report describes an HRA (Human Reliability Assessment) of six generic tasks and four Perfor-mance Shaping Factors (PSFs) targeted at railway operations commissioned by Banedanmark. The selection and characterization of generic tasks and PSFs are elaborated by DTU Management in close...

  16. Inflectional Morphology and Dyslexia: Italian Children's Performance in a Nonword Pluralization Task

    Science.gov (United States)

    Vender, Maria; Mantione, Federica; Savazzi, Silvia; Delfitto, Denis; Melloni, Chiara

    2017-01-01

    In this study, we present the results of an original experimental protocol designed to assess the performance in a pluralization task of 52 Italian children divided into two groups: 24 children with developmental dyslexia (mean age 10.0 years old) and 28 typically developing children (mean age 9.11 years old). Our task, inspired by Berko's Wug…

  17. 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.

  18. An Initial Investigation of Factors Affecting Multi-Task Performance

    National Research Council Canada - National Science Library

    Branscome, Tersa A; Swoboda, Jennifer C; Fatkin, Linda T

    2007-01-01

    This report presents the results of the first in a series of investigations designed to increase fundamental knowledge and understanding of the factors affecting multi-task performance in a military environment...

  19. 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.

  20. Task Performance with List-Mode Data

    Science.gov (United States)

    Caucci, Luca

    This dissertation investigates the application of list-mode data to detection, estimation, and image reconstruction problems, with an emphasis on emission tomography in medical imaging. We begin by introducing a theoretical framework for list-mode data and we use it to define two observers that operate on list-mode data. These observers are applied to the problem of detecting a signal (known in shape and location) buried in a random lumpy background. We then consider maximum-likelihood methods for the estimation of numerical parameters from list-mode data, and we characterize the performance of these estimators via the so-called Fisher information matrix. Reconstruction from PET list-mode data is then considered. In a process we called "double maximum-likelihood" reconstruction, we consider a simple PET imaging system and we use maximum-likelihood methods to first estimate a parameter vector for each pair of gamma-ray photons that is detected by the hardware. The collection of these parameter vectors forms a list, which is then fed to another maximum-likelihood algorithm for volumetric reconstruction over a grid of voxels. Efficient parallel implementation of the algorithms discussed above is then presented. In this work, we take advantage of two low-cost, mass-produced computing platforms that have recently appeared on the market, and we provide some details on implementing our algorithms on these devices. We conclude this dissertation work by elaborating on a possible application of list-mode data to X-ray digital mammography. We argue that today's CMOS detectors and computing platforms have become fast enough to make X-ray digital mammography list-mode data acquisition and processing feasible.

  1. Path Analysis Examining Self-Efficacy and Decision-Making Performance on a Simulated Baseball Task

    Science.gov (United States)

    Hepler, Teri J.; Feltz, Deborah L.

    2012-01-01

    The purpose of this study was to examine the relationship between decision-making self-efficacy and decision-making performance in sport. Undergraduate students (N = 78) performed 10 trials of a decision-making task in baseball. Self-efficacy was measured before performing each trial. Decision-making performance was assessed by decision speed and…

  2. 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).

  3. Training self-assessment and task-selection skills : A cognitive approach to improving self-regulated learning

    NARCIS (Netherlands)

    Kostons, Danny; van Gog, Tamara; Paas, Fred

    For self-regulated learning to be effective, students need to be able to accurately assess their own performance on a learning task and use this assessment for the selection of a new learning task. Evidence suggests, however, that students have difficulties with accurate self-assessment and task

  4. Performance on verbal and low-verbal false belief tasks: evidence from children with Williams syndrome.

    Science.gov (United States)

    Van Herwegen, Jo; Dimitriou, Dagmara; Rundblad, Gabriella

    2013-01-01

    Previous studies that have investigated the relationship between performance on theory of mind (ToM) tasks and verbal abilities in individuals with Williams syndrome (WS) have reported contradictory findings with some showing that language abilities aid performance on ToM tasks while others have found that participants with WS fail these tasks because of their verbal demands. The current study investigated this relationship again comparing performance on a classical change-location task to two newly developed low-verbal tasks, one change-location task and one unexpected content task. Thirty children with WS (aged 5-17;01 years) and 30 typically developing (TD) children (aged between 2;10 years and 9;09 years), who were matched for vocabulary comprehension scores were included in the study. Although performance in the WS group was significantly poorer compared to the TD group on all three tasks, performance was not predicted by their receptive vocabulary or grammatical ability scores. In addition, ToM abilities in both groups depended on the cognitive demands of the task at hand. This finding shows that performance on ToM tasks in WS is not necessarily hindered by their delayed language abilities but rather by the task administered. This could potentially affect the diagnosis of developmental disorders, such as Autism Spectrum Disorders, and comparison of ToM abilities across developmental disorders. Readers of this article should be able to (1) describe the current state of theory of mind research in Williams syndrome, (2) identify which cognitive abilities might explain performance on theory of mind tasks in both typically developing children and in children with Williams syndrome, and (3) interpret the importance of task demands when assessing children's theory of mind abilities. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Dual-Task Assessment Protocols in Concussion Assessment: A Systematic Literature Review.

    Science.gov (United States)

    Kleiner, Michelle; Wong, Lynne; Dubé, Alexandra; Wnuk, Katie; Hunter, Susan W; Graham, Laura J

    2018-02-01

    Study Design Systematic review. Background When assessed in isolation, balance and neurocognitive testing may not be sufficiently responsive to capture changes that occur with concussion. Normal daily activities require simultaneous cognitive and physical demands. Therefore, a dual-task assessment paradigm should be considered to identify performance deficits. Objectives To evaluate the literature and to identify dual-task testing protocols associated with changes in gait after concussion. Methods A systematic review of articles of individuals with concussion who underwent dual-task testing with a combination of motor and cognitive tasks was conducted. The AMED, CINAHL, Embase, PsycINFO, PubMed, Scopus, SPORTDiscus, and Web of Science databases and gray literature were searched from inception to January 29, 2017. Title and abstract, full-text, and quality review and data abstraction were performed by 2 independent reviewers. Results Twenty-four articles met the inclusion criteria. Eleven articles reported decreased gait velocity and increased medial-lateral displacement for individuals with concussion during dual-task conditions. Overall, included articles were of poor to moderate methodological quality. Fifteen articles used the same participants and data sets, creating a threat to validity and limiting the ability to make conclusions. Conclusion A deterioration in gait performance during dual-task testing is present among people with concussion. Specific recommendations for the use of a dual-task protocol to assess individuals with suspected concussion injury in a clinical setting have yet to be determined. J Orthop Sports Phys Ther 2018;48(2):87-103. Epub 7 Nov 2017. doi:10.2519/jospt.2018.7432.

  6. Exploring approaches to dietetic assessment of a common task across different universities through assessment moderation.

    Science.gov (United States)

    Palermo, C; Volders, E; Gibson, S; Kennedy, M; Wray, A; Thomas, J; Hannan-Jones, M; Gallegos, D; Beck, E

    2018-02-01

    Assessment presents one of the greatest challenges to evaluating health professional trainee performance, as a result of the subjectivity of judgements and variability in assessor standards. The present study aimed to test a moderation procedure for assessment across four independent universities and explore approaches to assessment and the factors that influence assessment decisions. Assessment tasks designed independently by each of the four universities to assess student readiness for placement were chosen for the present study. Each university provided four student performance recordings for moderation. Eight different academic assessors viewed the student performances and assessed them using the corresponding university assessment instrument. Assessment results were collated and presented back to the assessors, together with the original university assessment results. Results were discussed with assessors to explore variations. The discussion was recorded, transcribed, thematically analysed and presented back to all assessors to achieve consensus on the emerging major learnings. Although there were differences in absolute scores, there was consistency (12 out of 16 performances) in overall judgement decisions regarding placement readiness. Proficient communication skills were considered a key factor when determining placement readiness. The discussion revealed: (i) assessment instruments; (ii) assessor factors; and (iii) the subjectivity of judgement as the major factors influencing assessment. Assessment moderation is a useful method for improving the quality of assessment decisions by sharing understanding and aligning standards of performance. © 2017 The British Dietetic Association Ltd.

  7. 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

  8. Motivation, intentionality, and mind wandering: Implications for assessments of task-unrelated thought.

    Science.gov (United States)

    Seli, Paul; Cheyne, James Allan; Xu, Mengran; Purdon, Christine; Smilek, Daniel

    2015-09-01

    Researchers of mind wandering frequently assume that (a) participants are motivated to do well on the tasks they are given, and (b) task-unrelated thoughts (TUTs) that occur during task performance reflect unintentional, unwanted thoughts that occur despite participants' best intentions to maintain task-focus. Given the relatively boring and tedious nature of most mind-wandering tasks, however, there is the possibility that some participants have little motivation to do well on such tasks, and that this lack of motivation might in turn result in increases specifically in intentional TUTs. In the present study, we explored these possibilities, finding that individuals reporting lower motivation to perform well on a sustained-attention task reported more intentional relative to unintentional TUTs compared with individuals reporting higher motivation. Interestingly, our results indicate that the extent to which participants engage in intentional versus unintentional TUTs does not differentially relate to performance: both types of off-task thought were found to be equally associated with performance decrements. Participants with low levels of task-motivation also engaged in more overall TUTs, however, and this increase in TUTs was associated with greater performance decrements. We discuss these findings in the context of the literature on mind wandering, highlighting the importance of assessing the intentionality of TUTs and motivation to perform well on tasks assessing mind wandering. (c) 2015 APA, all rights reserved).

  9. 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 ...

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

    Science.gov (United States)

    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.; hide

    2011-01-01

    Space flight is known to cause alterations in multiple physiological systems including changes in sensorimotor, cardiovascular, and neuromuscular systems. These changes may affect a crewmember s ability to perform critical mission tasks immediately after landing on a planetary surface. The overall goal of this project is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. This presentation will focus on the sensorimotor contributions to postflight functional performance.

  11. Monitoring supports performance in a dual-task paradigm involving a risky decision-making task and a working memory task

    Directory of Open Access Journals (Sweden)

    Bettina eGathmann

    2015-02-01

    Full Text Available Performing two cognitively demanding tasks at the same time is known to decrease performance. The current study investigates the underlying executive functions of a dual-tasking situation involving the simultaneous performance of decision making under explicit risk and a working memory task. It is suggested that making a decision and performing a working memory task at the same time should particularly require monitoring - an executive control process supervising behavior and the state of processing on two tasks. To test the role of a supervisory/monitoring function in such a dual-tasking situation we investigated 122 participants with the Game of Dice Task plus 2-back task (GDT plus 2-back task. This dual task requires participants to make decisions under risk and to perform a 2-back working memory task at the same time. Furthermore, a task measuring a set of several executive functions gathered in the term concept formation (Modified Card Sorting Test, MCST and the newly developed Balanced Switching Task (BST, measuring monitoring in particular, were used. The results demonstrate that concept formation and monitoring are involved in the simultaneous performance of decision making under risk and a working memory task. In particular, the mediation analysis revealed that BST performance partially mediates the influence of MCST performance on the GDT plus 2-back task. These findings suggest that monitoring is one important subfunction for superior performance in a dual-tasking situation including decision making under risk and a working memory task.

  12. Monitoring supports performance in a dual-task paradigm involving a risky decision-making task and a working memory task

    Science.gov (United States)

    Gathmann, Bettina; Schiebener, Johannes; Wolf, Oliver T.; Brand, Matthias

    2015-01-01

    Performing two cognitively demanding tasks at the same time is known to decrease performance. The current study investigates the underlying executive functions of a dual-tasking situation involving the simultaneous performance of decision making under explicit risk and a working memory task. It is suggested that making a decision and performing a working memory task at the same time should particularly require monitoring—an executive control process supervising behavior and the state of processing on two tasks. To test the role of a supervisory/monitoring function in such a dual-tasking situation we investigated 122 participants with the Game of Dice Task plus 2-back task (GDT plus 2-back task). This dual task requires participants to make decisions under risk and to perform a 2-back working memory task at the same time. Furthermore, a task measuring a set of several executive functions gathered in the term concept formation (Modified Card Sorting Test, MCST) and the newly developed Balanced Switching Task (BST), measuring monitoring in particular, were used. The results demonstrate that concept formation and monitoring are involved in the simultaneous performance of decision making under risk and a working memory task. In particular, the mediation analysis revealed that BST performance partially mediates the influence of MCST performance on the GDT plus 2-back task. These findings suggest that monitoring is one important subfunction for superior performance in a dual-tasking situation including decision making under risk and a working memory task. PMID:25741308

  13. Improving Physical Task Performance with Counterfactual and Prefactual Thinking.

    Science.gov (United States)

    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.

  14. 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

  15. 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

  16. Game elements improve performance in a working memory training task

    Directory of Open Access Journals (Sweden)

    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. 

  17. 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.

  18. 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.

  19. Task Analysis Assessment on Intrastate Bus Traffic Controllers

    Science.gov (United States)

    Yen Bin, Teo; Azlis-Sani, Jalil; Nur Annuar Mohd Yunos, Muhammad; Ismail, S. M. Sabri S. M.; Tajedi, Noor Aqilah Ahmad

    2016-11-01

    Public transportation acts as social mobility and caters the daily needs of the society for passengers to travel from one place to another. This is true for a country like Malaysia where international trade has been growing significantly over the past few decades. Task analysis assessment was conducted with the consideration of cognitive ergonomic view towards problem related to human factors. Conducting research regarding the task analysis on bus traffic controllers had allowed a better understanding regarding the nature of work and the overall monitoring activities of the bus services. This paper served to study the task analysis assessment on intrastate bus traffic controllers and the objectives of this study include to conduct task analysis assessment on the bus traffic controllers. Task analysis assessment for the bus traffic controllers was developed via Hierarchical Task Analysis (HTA). There are a total of five subsidiary tasks on level one and only two were able to be further broken down in level two. Development of HTA allowed a better understanding regarding the work and this could further ease the evaluation of the tasks conducted by the bus traffic controllers. Thus, human error could be reduced for the safety of all passengers and increase the overall efficiency of the system. Besides, it could assist in improving the operation of the bus traffic controllers by modelling or synthesizing the existing tasks if necessary.

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

    Science.gov (United States)

    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.

  1. On the use of drawing tasks in neuropsychological assessment.

    Science.gov (United States)

    Smith, Alastair D

    2009-03-01

    Drawing tasks have attained a central position in neuropsychological assessment and are considered a rich source of information about the presence (or absence) of cognitive and perceptuo-motor abilities. However, unlike other tests of cognitive impairment, drawing tasks are often administered without reference to normative models of graphic production, and their results are often analyzed qualitatively. I begin this article by delineating the different ways in which drawing errors have been used to indicate particular functional deficits in neurological patients. I then describe models of drawing that have been explicitly based on the errors observed in patient drawings. Finally, the case is made for developing a more sensitive set of metrics in order to quantitatively assess patient performance. By providing a finer grain of analysis to assessment we will not only be better able to characterize the consequences of cognitive dysfunction, but may also be able to more subtly characterize and dissociate patients who would otherwise have been placed in the same broad category of impairment. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  2. Simplified Predictive Models for CO2 Sequestration Performance Assessment: Research Topical Report on Task #4 - Reduced-Order Method (ROM) Based Models

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Srikanta; Jin, Larry; He, Jincong; Durlofsky, Louis

    2015-06-30

    Reduced-order models provide a means for greatly accelerating the detailed simulations that will be required to manage CO2 storage operations. In this work, we investigate the use of one such method, POD-TPWL, which has previously been shown to be effective in oil reservoir simulation problems. This method combines trajectory piecewise linearization (TPWL), in which the solution to a new (test) problem is represented through a linearization around the solution to a previously-simulated (training) problem, with proper orthogonal decomposition (POD), which enables solution states to be expressed in terms of a relatively small number of parameters. We describe the application of POD-TPWL for CO2-water systems simulated using a compositional procedure. Stanford’s Automatic Differentiation-based General Purpose Research Simulator (AD-GPRS) performs the full-order training simulations and provides the output (derivative matrices and system states) required by the POD-TPWL method. A new POD-TPWL capability introduced in this work is the use of horizontal injection wells that operate under rate (rather than bottom-hole pressure) control. Simulation results are presented for CO2 injection into a synthetic aquifer and into a simplified model of the Mount Simon formation. Test cases involve the use of time-varying well controls that differ from those used in training runs. Results of reasonable accuracy are consistently achieved for relevant well quantities. Runtime speedups of around a factor of 370 relative to full- order AD-GPRS simulations are achieved, though the preprocessing needed for POD-TPWL model construction corresponds to the computational requirements for about 2.3 full-order simulation runs. A preliminary treatment for POD-TPWL modeling in which test cases differ from training runs in terms of geological parameters (rather than well controls) is also presented. Results in this case involve only small differences between

  3. Power performance assessment. Final report

    International Nuclear Information System (INIS)

    Frandsen, S.

    1998-12-01

    In the increasingly commercialised wind power marketplace, the lack of precise assessment methods for the output of an investment is becoming a barrier for wider penetration of wind power. Thus, addressing this problem, the overall objectives of the project are to reduce the financial risk in investment in wind power projects by significantly improving the power performance assessment methods. Ultimately, if this objective is successfully met, the project may also result in improved tuning of the individual wind turbines and in optimisation methods for wind farm operation. The immediate, measurable objectives of the project are: To prepare a review of existing contractual aspects of power performance verification procedures of wind farms; to provide information on production sensitivity to specific terrain characteristics and wind turbine parameters by analyses of a larger number of wind farm power performance data available to the proposers; to improve the understanding of the physical parameters connected to power performance in complex environment by comparing real-life wind farm power performance data with 3D computational flow models and 3D-turbulence wind turbine models; to develop the statistical framework including uncertainty analysis for power performance assessment in complex environments; and to propose one or more procedures for power performance evaluation of wind power plants in complex environments to be applied in contractual agreements between purchasers and manufacturers on production warranties. Although the focus in this project is on power performance assessment the possible results will also be of benefit to energy yield forecasting, since the two tasks are strongly related. (au) JOULE III. 66 refs.; In Co-operation Renewable Energy System Ltd. (GB); Centre for Renewable Energy (GR); Aeronautic Research Centre (SE); National Engineering Lab. (GB); Public Power Cooperation (GR)

  4. Assessing Scientific Performance.

    Science.gov (United States)

    Weiner, John M.; And Others

    1984-01-01

    A method for assessing scientific performance based on relationships displayed numerically in published documents is proposed and illustrated using published documents in pediatric oncology for the period 1979-1982. Contributions of a major clinical investigations group, the Childrens Cancer Study Group, are analyzed. Twenty-nine references are…

  5. 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

  6. Performance assessment calculational exercises

    International Nuclear Information System (INIS)

    Barnard, R.W.; Dockery, H.A.

    1990-01-01

    The Performance Assessment Calculational Exercises (PACE) are an ongoing effort coordinated by Yucca Mountain Project Office. The objectives of fiscal year 1990 work, termed PACE-90, as outlined in the Department of Energy Performance Assessment (PA) Implementation Plan were to develop PA capabilities among Yucca Mountain Project (YMP) participants by calculating performance of a Yucca Mountain (YM) repository under ''expected'' and also ''disturbed'' conditions, to identify critical elements and processes necessary to assess the performance of YM, and to perform sensitivity studies on key parameters. It was expected that the PACE problems would aid in development of conceptual models and eventual evaluation of site data. The PACE-90 participants calculated transport of a selected set of radionuclides through a portion of Yucca Mountain for a period of 100,000 years. Results include analyses of fluid-flow profiles, development of a source term for radionuclide release, and simulations of contaminant transport in the fluid-flow field. Later work included development of a problem definition for perturbations to the originally modeled conditions and for some parametric sensitivity studies. 3 refs

  7. Context for performance assessment

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1997-01-01

    In developing its recommendations on performance assessment for disposal of low-level radioactive waste, Scientific committee 87-3 of the National Council on Radiation Protection and Measurements (NCRP) has considered a number of topics that provide a context for the development of suitable approaches to performance assessment. This paper summarizes the Committee' discussions on these topics, including (1) the definition of low-level waste and its sources and properties, as they affect the variety of wastes that must be considered, (2) fundamental objectives and principles of radioactive waste disposal and their application to low-level waste, (3) current performance objectives for low-level waste disposal in the US, with particular emphasis on such unresolved issues of importance to performance assessment as the time frame for compliance, requirements for protection of groundwater and surface water, inclusion of doses from radon, demonstrating compliance with fixed performance objectives using highly uncertain model projections, and application of the principle that releases to the environment should be maintained as low as reasonably achievable (ALARA), (4) the role of active and passive institutional controls over disposal sites, (5) the role of the inadvertent human intruder in low-level waste disposal, (6) model validation and confidence in model outcomes, and (7) the concept of reasonable assurance of compliance

  8. Texas' performance assessment work

    International Nuclear Information System (INIS)

    Charbeneau, R.J.; Hertel, N.E.; Pollard, C.G.

    1990-01-01

    The Texas Low-Level Radioactive Waste Disposal Authority is completing two years of detailed on-site suitability studies of a potential low-level radioactive waste disposal site in Hudspeth County, Texas. The data from these studies have been used to estimate site specific parameters needed to do a performance assessment of the site. The radiological impacts of the site have been analyzed as required for a license application. The approach adopted for the performance assessment was to use simplified and yet conservative assumptions with regard to releases, radionuclide transport, and dose calculations. The methodologies employed in the performance assessment are reviewed in the paper. Rather than rely on a single computer code, a modular approach to the performance assessment was selected. The HELP code was used to calculate the infiltration rate through the trench covers and the amount of leachate released from this arid site. Individual pathway analyses used spreadsheet calculations. These calculations were compared with those from other computer models including CRRIS, INGDOS, PATHRAE, and MICROSHIELD copyright, and found to yield conservative estimates of the effective whole body dose. The greatest difficulty in performing the radiological assessment of the site was the selection of reasonable source terms for release into the environment. A surface water pathway is unreasonable for the site. Though also unlikely, the groundwater pathway with exposure through a site boundary well was found to yield the largest calculated dose. The more likely pathway including transport of leachate from the facility through the unsaturated zone and returning to the ground surface yields small doses. All calculated doses associated with normal releases of radioactivity are below the regulatory limits

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

    Science.gov (United States)

    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.

  10. Using the Hand Laterality Judgement Task to Assess Motor Imagery: A Study of Practice Effects in Repeated Measurements

    Science.gov (United States)

    Boonstra, Anne M.; de Vries, Sjoerd J.; Veenstra, Evelien; Tepper, Marga; Feenstra, Wya; Otten, Egbert

    2012-01-01

    The aim of this study was to determine whether there is a practice effect on the Hand Laterality Judgement Task (HLJT). The HLJT task is a mental rotation task that can be used to assess motor imagery ability in stroke patients. Thirty-three healthy individuals performed the HLJT and two control tasks twice at a 3-week interval. Differences in the…

  11. 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

  12. Performance assessment in algebra learning process

    Science.gov (United States)

    Lestariani, Ida; Sujadi, Imam; Pramudya, Ikrar

    2017-12-01

    The purpose of research to describe the implementation of performance assessment on algebra learning process. The subject in this research is math educator of SMAN 1 Ngawi class X. This research includes descriptive qualitative research type. Techniques of data collecting are done by observation method, interview, and documentation. Data analysis technique is done by data reduction, data presentation, and conclusion. The results showed any indication that the steps taken by the educator in applying the performance assessment are 1) preparing individual worksheets and group worksheets, 2) preparing rubric assessments for independent worksheets and groups and 3) making performance assessments rubric to learners’ performance results with individual or groups task.

  13. 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

  14. Performing the lockout/tagout risk assessment.

    Science.gov (United States)

    Wallace, W Jon

    2007-03-01

    Lockout/tagout provides the greatest level routine, repetitive, and integral to the production process, a risk assessment should be performed. If the task performed poses an unacceptable risk, acceptable risk reduction methods should be implemented to reduce the risk to acceptable levels.

  15. TWTF project criticality task force final review and assessment

    International Nuclear Information System (INIS)

    McKinley, K.B.; Cannon, J.W.; Wheeler, F.J.; Worle, H.A.

    1980-11-01

    The Transuranic Waste Treatment Facility (TWTF) is being developed to process transuranic waste, stored and buried at the Idaho National Engineering Laboratory, into a chemically inert, physically stable basalt-like residue acceptable at a federal repository. A task force was assembled by the TWTF Project Division to review and assess all aspects of criticality safety for the TWTF. This document presents the final review, assessments, and recommendations of this task force. The following conclusions were made: Additional criticality studies are needed for the entire envelope of feed compositions and temperature effects. Safe operating k/sub eff/'s need to be determined for process components. Criticality analyses validation experiments may also be required. SRP neutron interrogation should be replaced by DDT neutron interrogation. Accuracy studies need to be performed for the proposed assaying techniques. Time-correlated neutron monitoring needs to be mocked up for process components to prove feasibility and determine accuracy. The criticality control techniques developed for the TWTF conceptual design are in compliance with ERDAM 0530, including the Double Contingency Rule. Detailed procedures and controls need to be developed

  16. 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.

  17. Career-Oriented Performance Tasks in Chemistry: Effects on Students Integrated Science Process Skills

    OpenAIRE

    Allen A. Espinosa; Sheryl Lyn C. Monterola; Amelia E. Punzalan

    2013-01-01

    The study was conducted to assess the effectiveness of Career-Oriented Performance Task (COPT) approach against the traditional teaching approach (TTA) in enhancing students’ integrated science process skills. Specifically, it sought to find out if students exposed to COPT have higher integrated science process skills than those students exposed to the traditional teaching approach (TTA). Career-Oriented Performance Task (COPT) approach aims to integrate career-oriented examples and inquiry-b...

  18. Performing a secondary executive task with affective stimuli interferes with decision making under risk conditions.

    Science.gov (United States)

    Gathmann, Bettina; Pawlikowski, Mirko; Schöler, Tobias; Brand, Matthias

    2014-05-01

    Previous studies demonstrated that executive functions are crucial for advantageous decision making under risk and that therefore decision making is disrupted when working memory capacity is demanded while working on a decision task. While some studies also showed that emotions can affect decision making under risk, it is unclear how affective processing and executive functions predict decision-making performance in interaction. The current experimental study used a between-subjects design to examine whether affective pictures (positive and negative pictures compared to neutral pictures), included in a parallel executive task (working memory 2-back task), have an impact on decision making under risk as assessed by the Game of Dice Task (GDT). Moreover, the performance GDT plus 2-back task was compared to the performance in the GDT without any additional task (GDT solely). The results show that the performance in the GDT differed between groups (positive, negative, neutral, and GDT solely). The groups with affective pictures, especially those with positive pictures in the 2-back task, showed more disadvantageous decisions in the GDT than the groups with neutral pictures and the group performing the GDT without any additional task. However, executive functions moderated the effect of the affective pictures. Regardless of affective influence, subjects with good executive functions performed advantageously in the GDT. These findings support the assumption that executive functions and emotional processing interact in predicting decision making under risk.

  19. Relationships among gender, cognitive style, academic major, and performance on the Piaget water-level task.

    Science.gov (United States)

    Hammer, R E; Hoffer, N; King, W L

    1995-06-01

    Many researchers have found that more college-age adults than would be expected fail Piaget's water-level task, with women failing more frequently than men. It has been hypothesized that differences in cognitive style may account for performance differences on the water-level task. In the present study, 27 male and 27 female architectural students and 27 male and 27 female liberal-arts students were assessed for their performance on both Piaget's Water-level Task and Witkin's Group Embedded Figures Test. No difference was found in performance of male and female architectural students on either task, but male liberal-arts students scored significantly higher than female liberal-arts students on both measures. A disembedding cognitive style predicted success on the water-level task for the architectural students but not for the liberal arts students.

  20. 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.

  1. Preempting Performance Challenges: The Effects of Inoculation Messaging on Attacks to Task Self-Efficacy

    Science.gov (United States)

    Jackson, Ben; Compton, Josh; Whiddett, Ryan; Anthony, David R.; Dimmock, James A.

    2015-01-01

    Although inoculation messages have been shown to be effective for inducing resistance to counter-attitudinal attacks, researchers have devoted relatively little attention toward studying the way in which inoculation theory principles might support challenges to psychological phenomena other than attitudes (e.g., self-efficacy). Prior to completing a physical (i.e., balance) task, undergraduates (N = 127, Mage = 19.20, SD = 2.16) were randomly assigned to receive either a control or inoculation message, and reported their confidence in their ability regarding the upcoming task. During the task, a confederate provided standardized negative feedback to all participants regarding their performance, and following the completion of the task, participants again reported their self-efficacy along with measures assessing in-task processes. Findings supported the viability of efficacy inoculation; controlling for pre-task self-efficacy, task performance, and relevant psycho-social variables (e.g., resilience, self-confidence robustness), participants in the inoculation condition reported greater confidence in their ability (i.e., task self-efficacy) than those in the control condition at post-task. Relative to those in the inoculation condition, participants in the control condition also experienced greater concentration disruption and self-presentation concerns during the task. PMID:25898287

  2. 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.

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

    Science.gov (United States)

    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.

  4. 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...

  5. Self-reported and Observed Quality of ADL Task Performance in Adults with Depression

    DEFF Research Database (Denmark)

    Nielsen, Kristina Tomra; Wæhrens, Eva

    diagnosed with depression (range 19-79, median 45,5) Procedure In order to evaluate the participants’ self-reported and observed quality of ADL task performance the ADL-Interview (ADL-I) and the Assessment of Motor and Process Skills (AMPS) were chosen. Both instruments are developed to evaluate and measure...... the quality of ADL task performance. The ADL-I was conducted first and thereby formed the basis for identifying relevant tasks for the AMPS evaluation. Both evaluations were conducted on the same day by trained and calibrated occupational therapists. Results The results indicated that the participants both...

  6. Waste package performance assessment

    International Nuclear Information System (INIS)

    Lester, D.H.

    1981-01-01

    This paper describes work undertaken to assess the life-expectancy and post-failure nuclide release behavior of high-level and waste packages in a geologic repository. The work involved integrating models of individual phenomena (such as heat transfer, corrosion, package deformation, and nuclide transport) and using existing data to make estimates of post-emplacement behavior of waste packages. A package performance assessment code was developed to predict time to package failure in a flooded repository and subsequent transport of nuclides out of the leaking package. The model has been used to evaluate preliminary package designs. The results indicate, that within the limitation of model assumptions and data base, packages lasting a few hundreds of years could be developed. Very long lived packages may be possible but more comprehensive data are needed to confirm this

  7. 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.

  8. 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.

  9. Task conflict asymmetries : Effects on expectations and performance

    NARCIS (Netherlands)

    Jehn, Karen A.; De Wit, Frank R C; Barreto, Manuela; Rink, Floor

    2015-01-01

    Purpose-The purpose of this paper is to examine the effects of asymmetric perceptions of task conflict (i.e. one person experiencing more conflict than the other) on the anticipated relationship with the partner, as well as subjective and objective performance. Design/methodology/approach–In a 2= 2

  10. Effects of Refresher Training on Job-Task Typewriting Performance.

    Science.gov (United States)

    Hagman, Joseph D.; Schendel, Joel D.

    Two groups of 15 Administrative Specialists, 7lL Military Occupational Speciality (MOS), participated in four job-task refresher training sessions designed to enhance the typewriting of military correspondence. One group performed under a study training method which allowed use of a Correspondence Manual while arranging materials into the correct…

  11. Effects of Social Incentives on Task Performance in the Elderly

    Science.gov (United States)

    Levendusky, Philip G.

    1978-01-01

    The performance of 60 elderly volunteers on two cancellation tasks was examined under one of three experimental conditions: social praise, social reproof, or no comment. The clear implications from these data are that social incentives may well facilitate behavioral change in the aged. (Author)

  12. 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)

  13. Ergonomic evaluation of tasks performed by female workers in the ...

    African Journals Online (AJOL)

    Two main types of task are performed by the female workers in the brick fields in the unorganized sectors viz, brick moulding and brick carrying. Modified Nordic Questionnaire and Body Part Discomfort (BPD) scale was applied on these workers to identify the MSDs and the zones of discomfort in different body parts.

  14. 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...

  15. Monitoring User-System Performance in Interactive Retrieval Tasks

    NARCIS (Netherlands)

    Boldareva, L.; de Vries, A.P.; Hiemstra, Djoerd

    Monitoring user-system performance in interactive search is a challenging task. Traditional measures of retrieval evaluation, based on recall and precision, are not of any use in real time, for they require a priori knowledge of relevant documents. This paper shows how a Shannon entropy-based

  16. Disentangling task and contextual performance : a multitrait-multimethod approach

    NARCIS (Netherlands)

    Demerouti, E.; Xanthopoulou, D.; Tsaousis, I.; Bakker, A.B.

    2014-01-01

    This study among 244 employees and their colleagues working in various sectors investigated the dimensionality of self-ratings and peer-ratings of task and contextual performance, using the scales of Goodman and Svyantek (1999). By applying the multitrait-multimethod approach, we examined the degree

  17. Factors Associated With Community Health Worker Performance Differ by Task in a Multi-Tasked Setting in Rural Zimbabwe.

    Science.gov (United States)

    Kambarami, Rukundo A; Mbuya, Mduduzi Nn; Pelletier, David; Fundira, Dadirai; Tavengwa, Naume V; Stoltzfus, Rebecca J

    2016-06-20

    Zimbabwe, like most low-income countries, faces health worker shortages. Community health workers (CHWs) bridge this gap by delivering essential health services and nutrition interventions to communities. However, as workloads increase, CHWs' ability to provide quality services may be compromised. We studied influences upon CHWs' performance related to pregnancy surveillance and nutrition and hygiene education in rural Zimbabwe. In the context of a cluster-randomized trial conducted in 2 rural districts between November 2012 and March 2015, 342 government-employed CHWs identified and referred pregnant women for early antenatal care and delivered household-level behavior change lessons about infant feeding and hygiene to more than 5,000 women. In 2013, we conducted a survey among 322 of the CHWs to assess the association between demographic and work characteristics and task performance. Exploratory factor analyses of the Likert-type survey questions produced 8 distinct and reliable constructs of job satisfaction and motivation, supervision, peer support, and feedback (Cronbach α range, 0.68 to 0.92). Pregnancy surveillance performance was assessed from pregnancy referrals, and nutrition and hygiene education performance was assessed by taking the average summative score (range, 5 to 30) of lesson delivery observations completed by a nurse supervisor using a 6-item Likert-type checklist. Poisson and multiple linear regressions were used to test associations between CHW demographic and work characteristics and performance. CHWs who referred more pregnant women were female, unmarried, under 40 years old, from larger households, and of longer tenure. They also perceived work resources to be adequate and received positive feedback from supervisors and the community, but they were less satisfied with remuneration. CHWs with high scores on behavior change lesson delivery were from smaller households, and they received more supportive supervision but less operational

  18. 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

  19. 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.

  20. Basic considerations in predicting error probabilities in human task performance

    International Nuclear Information System (INIS)

    Fleishman, E.A.; Buffardi, L.C.; Allen, J.A.; Gaskins, R.C. III

    1990-04-01

    It is well established that human error plays a major role in the malfunctioning of complex systems. This report takes a broad look at the study of human error and addresses the conceptual, methodological, and measurement issues involved in defining and describing errors in complex systems. In addition, a review of existing sources of human reliability data and approaches to human performance data base development is presented. Alternative task taxonomies, which are promising for establishing the comparability on nuclear and non-nuclear tasks, are also identified. Based on such taxonomic schemes, various data base prototypes for generalizing human error rates across settings are proposed. 60 refs., 3 figs., 7 tabs

  1. Task-irrelevant auditory feedback facilitates motor performance in musicians

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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…

  3. 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.

  4. Effects of a multicomponent exercise on dual-task performance and executive function among older adults

    Directory of Open Access Journals (Sweden)

    Ray-Yau Wang

    2018-06-01

    Full Text Available Summary: Background: Previous studies showed that multicomponent exercise enhanced physical and cognitive functions. This study aimed to investigate the effects of a multicomponent exercise on dual-task performance and executive function and to demonstrate the relationship between improvement in dual-task performance and enhancement in executive function among the elderly. Methods: A total of 27 people completed the intervention, with 16 in the experimental group and 11 in the control group. The 12-week multicomponent exercise lasted 1 h per day and 3 days per week. Participants' gait performance was assessed in dual-task conditions and executive function was examined at both pre- and post-intervention. Results: Results showed significant interaction effects of time x group on all selected gait parameters in both dual-task conditions and the Executive Interview. Compared with the control group, the experimental group showed greater improvements in most measures following intervention. Improved dual-task performance was correlated with enhanced executive function (r = 0.46–0.75. Conclusion: Our results suggested that a multicomponent exercise positively affects dual-task performance and executive function in the elderly. Keywords: Dual-task, Executive function, Exercise, Gait, Older adults

  5. The influences of obesity and age on functional performance during intermittent upper extremity tasks.

    Science.gov (United States)

    Cavuoto, Lora A; Nussbaum, Maury A

    2014-01-01

    In this study, the main and interactive effects of obesity and age on functional performance were assessed during intermittent exertions involving the upper extremity. The prevalence of obesity has doubled over the past 30 years and this increase is associated with higher health care costs, rates of workplace injury, and lost workdays. Obesity and aging can modify job demands and affect worker capacity in terms of muscular and psychomotor function. However, there is a lack of empirical studies quantifying the work-relevant (or ergonomic) impacts related to task demands, capacities, and their potential imbalance. Eight obese and eight non-obese participants from each of two age groups (18-25 and 50-65 years) completed three endurance tasks involving fixed levels of task demands: hand grip, shoulder flexion, and a simulated assembly task using the upper extremity. Measures of functional performance including endurance, discomfort, motor control, and task performance were recorded for each of the task conditions. Endurance times were ∼60% longer for the non-obese group, and older participants had longer endurance times; however there was no evidence of interactive effects of obesity and age. Obesity also impaired functional performance, as indicated by higher rates of strength loss, increases in discomfort, and declines in task performance. These observed impairments may reflect underlying physiological differences among individuals who are obese, but that are independent of age. Obesity-related impairments may have implications for the design of work duration and demand level to prevent fatigue development for workers who are obese.

  6. Functional Magnetic Resonance Imaging Correlates of First-Episode Psychoses during Attentional and Memory Task Performance.

    Science.gov (United States)

    Del Casale, Antonio; Kotzalidis, Georgios D; Rapinesi, Chiara; Sorice, Serena; Girardi, Nicoletta; Ferracuti, Stefano; Girardi, Paolo

    2016-01-01

    The nature of the alteration of the response to cognitive tasks in first-episode psychosis (FEP) still awaits clarification. We used activation likelihood estimation, an increasingly used method in evaluating normal and pathological brain function, to identify activation changes in functional magnetic resonance imaging (fMRI) studies of FEP during attentional and memory tasks. We included 11 peer-reviewed fMRI studies assessing FEP patients versus healthy controls (HCs) during performance of attentional and memory tasks. Our database comprised 290 patients with FEP, matched with 316 HCs. Between-group analyses showed that HCs, compared to FEP patients, exhibited hyperactivation of the right middle frontal gyrus (Brodmann area, BA, 9), right inferior parietal lobule (BA 40), and right insula (BA 13) during attentional task performances and hyperactivation of the left insula (BA 13) during memory task performances. Right frontal, parietal, and insular dysfunction during attentional task performance and left insular dysfunction during memory task performance are significant neural functional FEP correlates. © 2016 S. Karger AG, Basel.

  7. TURVA-2012: Performance assessment

    International Nuclear Information System (INIS)

    Hellae, Pirjo; Snellman, Margit; Marcos, Nuria; Pastina, Barbara; Smith, Paul; Koskinen, Kari

    2014-01-01

    TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. Posiva's safety concept is based on long-term isolation and containment, which is achieved through a robust engineered barrier system (EBS) design and favourable geological conditions at the repository site. The reference design considered in the TURVA-2012 safety case is the KBS-3V design, with the EBS consisting of a copper-iron canister, a buffer of swelling clay material, a backfill in the deposition tunnels of low-permeability material and closure of the central tunnels and other underground openings. The host rock acts as a natural barrier. Each barrier contributes to safety through one or more safety function. The conditions needed for the barriers to fulfil their respective safety functions are expressed in terms of performance targets for the EBS and the target properties for the host rock. The performance assessment (Posiva, 2013), which is a key component of TURVA-2012, analyses the ability of the repository system to provide containment and isolation of the spent nuclear fuel during the long-term evolution of the system and the site. The conditions needed for the barriers to fulfil their respective safety functions are expressed in terms of performance targets for the engineered barriers and target properties for the host rock, for example properties related to the corrosion resistance and mechanical strength of the canister as well as groundwater flow and composition. The analyses take into account the uncertainties in the initial state, the subsequent thermal, hydraulic, mechanical and chemical evolution of the repository system and uncertainties in the evolution. The conclusions of the performance assessment are based mostly on the output of key modelling activities. Whenever modelling is not possible the conclusions

  8. 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

  9. 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.

  10. 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.

  11. Effects of the Addition of a Dual Task to a Supervised Physical Exercise Program on Older Adults' Cognitive Performance.

    Science.gov (United States)

    Ansai, Juliana Hotta; de Andrade, Larissa Pires; de Souza Buto, Marcele Stephanie; de Vassimon Barroso, Verena; Farche, Ana Claudia Silva; Rossi, Paulo Giusti; de Medeiros Takahashi, Anielle Cristhine

    2017-04-01

    The purpose of this study was to investigate the effects of the addition of a dual task to multicomponent training on cognition of active older adults. Eighty physically active older adults were divided into an intervention group (IG) and a control group (CG). Both groups performed multicomponent training over 12 weeks. The IG simultaneously performed exercises and cognitive tasks. The Mini-Mental State Examination, the Montreal Cognitive Assessment, and the Clock Drawing Test were used for cognitive assessments. The Timed Up and Go Test associated with a cognitive task was used for dual-task assessment. Significant interactions were not observed between groups in terms of the cognitive variables or the dual-task performance. An interaction was observed only for Timed Up and Go Test performance, which was better in the CG than in the IG. Active older adults showed no improvement in cognition following the addition of the dual task to the multicomponent training.

  12. Predicting Subsequent Task Performance From Goal Motivation and Goal Failure

    Directory of Open Access Journals (Sweden)

    Laura Catherine Healy

    2015-07-01

    Full Text Available Recent research has demonstrated that the cognitive processes associated with goal pursuit can continue to interfere with unrelated tasks when a goal is unfulfilled. Drawing from the self-regulation and goal-striving literatures, the present study explored the impact of goal failure on subsequent cognitive and physical task performance. Furthermore, we examined if the autonomous or controlled motivation underpinning goal striving moderates the responses to goal failure. Athletes (75 male, 59 female, Mage = 19.90 years, SDage = 3.50 completed a cycling trial with the goal of covering a given distance in 8 minutes. Prior to the trial, their motivation was primed using a video. During the trial they were provided with manipulated performance feedback, thus creating conditions of goal success or failure. No differences emerged in the responses to goal failure between the primed motivation or performance feedback conditions. We make recommendations for future research into how individuals can deal with failure in goal striving.

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

    Science.gov (United States)

    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.

  14. 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.

  15. Effects on Task Performance and Psychophysiological Measures of Performance During Normobaric Hypoxia Exposure

    Science.gov (United States)

    Stephens, Chad; Kennedy, Kellie; Napoli, Nicholas; Demas, Matthew; Barnes, Laura; Crook, Brenda; Williams, Ralph; Last, Mary Carolyn; Schutte, Paul

    2017-01-01

    Human-autonomous systems have the potential to mitigate pilot cognitive impairment and improve aviation safety. A research team at NASA Langley conducted an experiment to study the impact of mild normobaric hypoxia induction on aircraft pilot performance and psychophysiological state. A within-subjects design involved non-hypoxic and hypoxic exposures while performing three 10-minute tasks. Results indicated the effect of 15,000 feet simulated altitude did not induce significant performance decrement but did produce increase in perceived workload. Analyses of psychophysiological responses evince the potential of biomarkers for hypoxia onset. This study represents on-going work at NASA intending to add to the current knowledge of psychophysiologically-based input to automation to increase aviation safety. Analyses involving coupling across physiological systems and wavelet transforms of cortical activity revealed patterns that can discern between the simulated altitude conditions. Specifically, multivariate entropy of ECG/Respiration components were found to be significant predictors (pTask performance was not appreciably impacted by the effect of 15,000 feet simulated altitude. Analyses of psychophysiological responses evince the potential of biomarkers for mild hypoxia onset.The potential for identifying shifts in underlying cortical and physiological systems could serve as a means to identify the onset of deteriorated cognitive state. Enabling such assessment in future flightdecks could permit increasingly autonomous systems-supported operations. Augmenting human operator through assessment of cognitive impairment has the potential to further improve operator performance and mitigate human error in safety critical contexts. This study represents ongoing work at NASA intending to add to the current knowledge of psychophysiologically-based input to automation to increase aviation safety.

  16. Group performance and group learning at dynamic system control tasks

    International Nuclear Information System (INIS)

    Drewes, Sylvana

    2013-01-01

    Proper management of dynamic systems (e.g. cooling systems of nuclear power plants or production and warehousing) is important to ensure public safety and economic success. So far, research has provided broad evidence for systematic shortcomings in individuals' control performance of dynamic systems. This research aims to investigate whether groups manifest synergy (Larson, 2010) and outperform individuals and if so, what processes lead to these performance advantages. In three experiments - including simulations of a nuclear power plant and a business setting - I compare the control performance of three-person-groups to the average individual performance and to nominal groups (N = 105 groups per experiment). The nominal group condition captures the statistical advantage of aggregated group judgements not due to social interaction. First, results show a superior performance of groups compared to individuals. Second, a meta-analysis across all three experiments shows interaction-based process gains in dynamic control tasks: Interacting groups outperform the average individual performance as well as the nominal group performance. Third, group interaction leads to stable individual improvements of group members that exceed practice effects. In sum, these results provide the first unequivocal evidence for interaction-based performance gains of groups in dynamic control tasks and imply that employers should rely on groups to provide opportunities for individual learning and to foster dynamic system control at its best.

  17. 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

  18. Beyond Behavioral Inhibition: A Computer Avatar Task Designed to Assess Behavioral Inhibition Extends to Harm Avoidance

    Directory of Open Access Journals (Sweden)

    Michael Todd Allen

    2017-09-01

    Full Text Available Personality factors such as behavioral inhibition (BI, a temperamental tendency for avoidance in the face of unfamiliar situations, have been identified as risk factors for anxiety disorders. Personality factors are generally identified through self-report inventories. However, this tendency to avoid may affect the accuracy of these self-report inventories. Previously, a computer based task was developed in which the participant guides an on-screen “avatar” through a series of onscreen events; performance on the task could accurately predict participants’ BI, measured by a standard paper and pencil questionnaire (Adult Measure of Behavioral Inhibition, or AMBI. Here, we sought to replicate this finding as well as compare performance on the avatar task to another measure related to BI, the harm avoidance (HA scale of the Tridimensional Personality Questionnaire (TPQ. The TPQ includes HA scales as well as scales assessing reward dependence (RD, novelty seeking (NS and persistence. One hundred and one undergraduates voluntarily completed the avatar task and the paper and pencil inventories in a counter-balanced order. Scores on the avatar task were strongly correlated with BI assessed via the AMBI questionnaire, which replicates prior findings. Females exhibited higher HA scores than males, but did not differ on scores on the avatar task. There was a strong positive relationship between scores on the avatar task and HA scores. One aspect of HA, fear of uncertainty was found to moderately mediate the relationship between AMBI scores and avatar scores. NS had a strong negative relationship with scores on the avatar task, but there was no significant relationship between RD and scores on the avatar task. These findings indicate the effectiveness of the avatar task as a behavioral alternative to self-report measures to assess avoidance. In addition, the use of computer based behavioral tasks are a viable alternative to paper and pencil self

  19. Workload assessment for mental arithmetic tasks using the task-evoked pupillary response

    Directory of Open Access Journals (Sweden)

    Gerhard Marquart

    2015-08-01

    Full Text Available Pupillometry is a promising method for assessing mental workload and could be helpful in the optimization of systems that involve human–computer interaction. The present study focuses on replicating the studies by Ahern (1978 and Klingner (2010, which found that for three levels of difficulty of mental multiplications, the more difficult multiplications yielded larger dilations of the pupil. Using a remote eye tracker, our research expands upon these two previous studies by statistically testing for each 1.5 s interval of the calculation period (1 the mean absolute pupil diameter (MPD, (2 the mean pupil diameter change (MPDC with respect to the pupil diameter during the pre-stimulus accommodation period, and (3 the mean pupil diameter change rate (MPDCR. An additional novelty of our research is that we compared the pupil diameter measures with a self-report measure of workload, the NASA Task Load Index (NASA-TLX, and with the mean blink rate (MBR. The results showed that the findings of Ahern and Klingner were replicated, and that the MPD and MPDC discriminated just as well between the lowest and highest difficulty levels as did the NASA-TLX. The MBR, on the other hand, did not differentiate between the difficulty levels. Moderate to strong correlations were found between the MPDC and the proportion of incorrect responses, indicating that the MPDC was higher for participants with a poorer performance. For practical applications, validity could be improved by combining pupillometry with other physiological techniques.

  20. Variations in task constraints shape emergent performance outcomes and complexity levels in balancing.

    Science.gov (United States)

    Caballero Sánchez, Carla; Barbado Murillo, David; Davids, Keith; Moreno Hernández, Francisco J

    2016-06-01

    This study investigated the extent to which specific interacting constraints of performance might increase or decrease the emergent complexity in a movement system, and whether this could affect the relationship between observed movement variability and the central nervous system's capacity to adapt to perturbations during balancing. Fifty-two healthy volunteers performed eight trials where different performance constraints were manipulated: task difficulty (three levels) and visual biofeedback conditions (with and without the center of pressure (COP) displacement and a target displayed). Balance performance was assessed using COP-based measures: mean velocity magnitude (MVM) and bivariate variable error (BVE). To assess the complexity of COP, fuzzy entropy (FE) and detrended fluctuation analysis (DFA) were computed. ANOVAs showed that MVM and BVE increased when task difficulty increased. During biofeedback conditions, individuals showed higher MVM but lower BVE at the easiest level of task difficulty. Overall, higher FE and lower DFA values were observed when biofeedback was available. On the other hand, FE reduced and DFA increased as difficulty level increased, in the presence of biofeedback. However, when biofeedback was not available, the opposite trend in FE and DFA values was observed. Regardless of changes to task constraints and the variable investigated, balance performance was positively related to complexity in every condition. Data revealed how specificity of task constraints can result in an increase or decrease in complexity emerging in a neurobiological system during balance performance.

  1. Assessing expertise in introductory physics using categorization task

    Directory of Open Access Journals (Sweden)

    Andrew Mason

    2011-10-01

    Full Text Available The ability to categorize problems based upon underlying principles, rather than surface features or contexts, is considered one of several proxy predictors of expertise in problem solving. With inspiration from the classic study by Chi, Feltovich, and Glaser, we assess the distribution of expertise among introductory physics students by asking three introductory physics classes, each with more than a hundred students, to categorize mechanics problems based upon similarity of solution. We compare their categorization with those of physics graduate students and faculty members. To evaluate the effect of problem context on students’ ability to categorize, two sets of problems were developed for categorization. Some problems in one set included those available from the prior study by Chi et al. We find a large overlap between calculus-based introductory students and graduate students with regard to their categorizations that were assessed as “good.” Our findings, which contrast with those of Chi et al., suggest that there is a wide distribution of expertise in mechanics among introductory and graduate students. Although the categorization task is conceptual, introductory students in the calculus-based course performed better than those in the algebra-based course. Qualitative trends in categorization of problems are similar between the non-Chi problems and problems available from the Chi study used in our study although the Chi problems used are more difficult on average.

  2. Trajectory generation for two robots cooperating to perform a task

    International Nuclear Information System (INIS)

    Lewis, C.L.

    1995-01-01

    This paper formulates an algorithm for trajectory generation for two robots cooperating to perform an assembly task. Treating the two robots as a single redundant system, this paper derives two Jacobian matrices which relate the joint rates of the entire system to the relative motion of the grippers with respect to one another. The advantage of this formulation over existing methods is that a variety of secondary criteria can be conveniently satisfied using motion in the null-space of the relative Jacobian. This paper presents methods for generating dual-arm joint trajectories which perform assembly tasks while at the same time avoiding obstacles and joint limits, and also maintaining constraints on the absolute position and orientation of the end-effectors

  3. Improving multitasking assessment in healthy older adults using a prop-based version of the Breakfast task.

    Science.gov (United States)

    Kosowicz, Maria; MacPherson, Sarah E

    2017-01-01

    Computerized cognitive assessment is becoming increasingly more common in clinical neuropsychological assessment and cognitive neuropsychological research. A number of computerized tasks now exist to assess multitasking abilities that are essential for everyday tasks such as cooking, shopping, or driving, but little is known about whether these tasks are appropriate for assessing older adults' multitasking. The present study directly compared age effects on multitasking when assessed using a computerized and a prop-based version of Craik and Bialystok's ( 2006 ) Breakfast task. Twenty participants aged 18 to 24 years and 20 participants aged 60 to 79 years were assessed on both versions of the Breakfast task. While age-related decrements in multitasking performance were found using the computerized task, significant age differences were not found on the majority of measures when the prop-based version was administered. The results suggest that age-related deficits in multitasking will be less when more contextualized, noncomputer based tasks are used.

  4. CREATING AUDIO VISUAL DIALOGUE TASK AS STUDENTS’ SELF ASSESSMENT TO ENHANCE THEIR SPEAKING ABILITY

    Directory of Open Access Journals (Sweden)

    Novia Trisanti

    2017-04-01

    Full Text Available The study is about giving overview of employing audio visual dialogue task as students creativity task and self assessment in EFL speaking class of tertiary education to enhance the students speaking ability. The qualitative research was done in one of the speaking classes at English Department, Semarang State University, Central Java, Indonesia. The results that can be seen from the rubric of self assessment show that the oral performance through audio visual recorded tasks done by the students as their self assessment gave positive evidences. The audio visual dialogue task can be very beneficial since it can motivate the students learning and increase their learning experiences. The self-assessment can be a valuable additional means to improve their speaking ability since it is one of the motives that drive self- evaluatioan, along with self- verification and self- enhancement.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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.

  7. Using the Hand Laterality Judgement Task to assess motor imagery : a study of practice effects in repeated measurements

    NARCIS (Netherlands)

    Boonstra, Anne M.; de Vries, Sjoerd J.; Veenstra, Evelien; Tepper, Marga; Feenstra, Wya; Otten, Egbert

    The aim of this study was to determine whether there is a practice effect on the Hand Laterality Judgement Task (HLJT). The HLJT task is a mental rotation task that can be used to assess motor imagery ability in stroke patients. Thirty-three healthy individuals performed the HLJT and two control

  8. Reliability and Validity of Dual-Task Mobility Assessments in People with Chronic Stroke

    Science.gov (United States)

    Yang, Lei; He, Chengqi; Pang, Marco Yiu Chung

    2016-01-01

    Background The ability to perform a cognitive task while walking simultaneously (dual-tasking) is important in real life. However, the psychometric properties of dual-task walking tests have not been well established in stroke. Objective To assess the test-retest reliability, concurrent and known-groups validity of various dual-task walking tests in people with chronic stroke. Design Observational measurement study with a test-retest design. Methods Eighty-eight individuals with chronic stroke participated. The testing protocol involved four walking tasks (walking forward at self-selected and maximal speed, walking backward at self-selected speed, and crossing over obstacles) performed simultaneously with each of the three attention-demanding tasks (verbal fluency, serial 3 subtractions or carrying a cup of water). For each dual-task condition, the time taken to complete the walking task, the correct response rate (CRR) of the cognitive task, and the dual-task effect (DTE) for the walking time and CRR were calculated. Forty-six of the participants were tested twice within 3–4 days to establish test-retest reliability. Results The walking time in various dual-task assessments demonstrated good to excellent reliability [Intraclass correlation coefficient (ICC2,1) = 0.70–0.93; relative minimal detectable change at 95% confidence level (MDC95%) = 29%-45%]. The reliability of the CRR (ICC2,1 = 0.58–0.81) and the DTE in walking time (ICC2,1 = 0.11–0.80) was more varied. The reliability of the DTE in CRR (ICC2,1 = -0.31–0.40) was poor to fair. The walking time and CRR obtained in various dual-task walking tests were moderately to strongly correlated with those of the dual-task Timed-up-and-Go test, thus demonstrating good concurrent validity. None of the tests could discriminate fallers (those who had sustained at least one fall in the past year) from non-fallers. Limitation The results are generalizable to community-dwelling individuals with chronic stroke only

  9. Georgia's Teacher Performance Assessment

    Science.gov (United States)

    Fenton, Anne Marie; Wetherington, Pamela

    2016-01-01

    Like most states, Georgia until recently depended on an assessment of content knowledge to award teaching licenses, along with a licensure recommendation from candidates' educator preparation programs. While the content assessment reflected candidates' grasp of subject matter, licensure decisions did not hinge on direct, statewide assessment of…

  10. 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

  11. 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.

  12. Towards Computerized Adaptive Assessment Based on Structured Tasks

    NARCIS (Netherlands)

    Tvarožek, Jozef; Kravcik, Milos; Bieliková, Mária

    2008-01-01

    Tvarožek, J., Kravčík, M., & Bieliková, M. (2008). Towards Computerized Adaptive Assessment Based on Structured Tasks. In W. Nejdl et al. (Eds.), Adaptive Hypermedia and Adaptive Web-Based Systems (pp. 224-234). Springer Berlin / Heidelberg.

  13. Investment Portfolio Simulation: An Assessment Task in Finance

    Science.gov (United States)

    Parle, Gabrielle; Laing, Gregory K.

    2017-01-01

    The use of an investment portfolio simulation as an assessment task is intended to reinforce learning by involving students in practical application of theoretical principles in a real-time actual financial market. Simulation as a teaching pedagogy promotes individual involvement and provides students with a deeper understanding of the issues, and…

  14. Assessment and Intervention for Academic Task Attack Strategy Competencies

    Science.gov (United States)

    Busse, R. T.; Lee, Charlene

    2015-01-01

    Many students who underachieve in schools may not be learning as effectively as they could. Direct assessments such as the Academic Competence Evaluation Scales (ACES), School Motivation and Learning Strategies Inventory (SMALSI), and the Academic Task Attack Checklist System (ATACS) can be used to evaluate students' knowledge and use of…

  15. 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.

  16. Visual Motor and Perceptual Task Performance in Astigmatic Students

    Directory of Open Access Journals (Sweden)

    Erin M. Harvey

    2017-01-01

    Full Text Available Purpose. To determine if spectacle corrected and uncorrected astigmats show reduced performance on visual motor and perceptual tasks. Methods. Third through 8th grade students were assigned to the low refractive error control group (astigmatism < 1.00 D, myopia < 0.75 D, hyperopia < 2.50 D, and anisometropia < 1.50 D or bilateral astigmatism group (right and left eye ≥ 1.00 D based on cycloplegic refraction. Students completed the Beery-Buktenica Developmental Test of Visual Motor Integration (VMI and Visual Perception (VMIp. Astigmats were randomly assigned to testing with/without correction and control group was tested uncorrected. Analyses compared VMI and VMIp scores for corrected and uncorrected astigmats to the control group. Results. The sample included 333 students (control group 170, astigmats tested with correction 75, and astigmats tested uncorrected 88. Mean VMI score in corrected astigmats did not differ from the control group (p=0.829. Uncorrected astigmats had lower VMI scores than the control group (p=0.038 and corrected astigmats (p=0.007. Mean VMIp scores for uncorrected (p=0.209 and corrected astigmats (p=0.124 did not differ from the control group. Uncorrected astigmats had lower mean scores than the corrected astigmats (p=0.003. Conclusions. Uncorrected astigmatism influences visual motor and perceptual task performance. Previously spectacle treated astigmats do not show developmental deficits on visual motor or perceptual tasks when tested with correction.

  17. Self-Associations Influence Task-Performance through Bayesian Inference.

    Science.gov (United States)

    Bengtsson, Sara L; Penny, Will D

    2013-01-01

    The way we think about ourselves impacts greatly on our behavior. This paper describes a behavioral study and a computational model that shed new light on this important area. Participants were primed "clever" and "stupid" using a scrambled sentence task, and we measured the effect on response time and error-rate on a rule-association task. First, we observed a confirmation bias effect in that associations to being "stupid" led to a gradual decrease in performance, whereas associations to being "clever" did not. Second, we observed that the activated self-concepts selectively modified attention toward one's performance. There was an early to late double dissociation in RTs in that primed "clever" resulted in RT increase following error responses, whereas primed "stupid" resulted in RT increase following correct responses. We propose a computational model of subjects' behavior based on the logic of the experimental task that involves two processes; memory for rules and the integration of rules with subsequent visual cues. The model incorporates an adaptive decision threshold based on Bayes rule, whereby decision thresholds are increased if integration was inferred to be faulty. Fitting the computational model to experimental data confirmed our hypothesis that priming affects the memory process. This model explains both the confirmation bias and double dissociation effects and demonstrates that Bayesian inferential principles can be used to study the effect of self-concepts on behavior.

  18. Self-associations influence task-performance through Bayesian inference

    Directory of Open Access Journals (Sweden)

    Sara L Bengtsson

    2013-08-01

    Full Text Available The way we think about ourselves impacts greatly on our behaviour. This paper describes a behavioural study and a computational model that sheds new light on this important area. Participants were primed 'clever' and 'stupid' using a scrambled sentence task, and we measured the effect on response time and error-rate on a rule-association task. First, we observed a confirmation bias effect in that associations to being 'stupid' led to a gradual decrease in performance, whereas associations to being 'clever' did not. Second, we observed that the activated self-concepts selectively modified attention towards one's performance. There was an early to late double dissociation in RTs in that primed 'clever' resulted in RT increase following error responses, whereas primed 'stupid' resulted in RT increase following correct responses. We propose a computational model of subjects' behaviour based on the logic of the experimental task that involves two processes; memory for rules and the integration of rules with subsequent visual cues. The model also incorporates an adaptive decision threshold based on Bayes rule, whereby decision thresholds are increased if integration was inferred to be faulty. Fitting the computational model to experimental data confirmed our hypothesis that priming affects the memory process. This model explains both the confirmation bias and double dissociation effects and demonstrates that Bayesian inferential principles can be used to study the effect of self-concepts on behaviour.

  19. System structure and cognitive ability as predictors of performance in dynamic system control tasks

    Directory of Open Access Journals (Sweden)

    Jan Hundertmark

    2015-12-01

    Full Text Available In dynamic system control, cognitive mechanisms and abilities underlying performance may vary depending on the nature of the task. We therefore investigated the effects of system structure and its interaction with cognitive abilities on system control performance. A sample of 127 university students completed a series of different system control tasks that were manipulated in terms of system size and recurrent feedback, either with or without a cognitive load manipulation. Cognitive abilities assessed included reasoning ability, working memory capacity, and cognitive reflection. System size and recurrent feedback affected overall performance as expected. Overall, the results support that cognitive ability is a good predictor of performance in dynamic system control tasks but predictiveness is reduced when the system structure contains recurrent feedback. We discuss this finding from a cognitive processing perspective as well as its implications for individual differences research in dynamic systems.

  20. The effect of dynamic workstations on the performance of various computer and office-based tasks

    NARCIS (Netherlands)

    Burford, E.M.; Botter, J.; Commissaris, D.; Könemann, R.; Hiemstra-Van Mastrigt, S.; Ellegast, R.P.

    2013-01-01

    The effect of different workstations, conventional and dynamic, on different types of performance measures for several different office and computer based task was investigated in this research paper. The two dynamic workstations assessed were the Lifespan Treadmill Desk and the RightAngle

  1. R&D manpower and technological performance : The impact of demographic and task-related diversity

    NARCIS (Netherlands)

    Faems, D.L.M.; Subramaniam, A.

    2013-01-01

    We assess the impact of R&D manpower diversity on firms' technological performance. Relying on insights from two theoretical perspectives on team diversity (i.e. social categorization perspective and information decision-making perspective), we hypothesize that both demographic and task-related

  2. Using Performance Tasks to Improve Quantitative Reasoning in an Introductory Mathematics Course

    Science.gov (United States)

    Kruse, Gerald; Drews, David

    2013-01-01

    A full-cycle assessment of our efforts to improve quantitative reasoning in an introductory math course is described. Our initial iteration substituted more open-ended performance tasks for the active learning projects than had been used. Using a quasi-experimental design, we compared multiple sections of the same course and found non-significant…

  3. Tower of Hanoi disk-transfer task: Influences of strategy knowledge and learning on performance

    NARCIS (Netherlands)

    Welsh, M.C.; Huizinga, M.

    2005-01-01

    Tower of Hanoi has become a popular tool in cognitive and neuropsychology to assess a set of behaviors collectively referred to as executive functions. Substantial variability in performance on the Tower of Hanoi (TOH) disk-transfer task among normally functioning young adults, and potential

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

    Science.gov (United States)

    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.

  5. Task demands moderate stereotype threat effects on memory performance.

    Science.gov (United States)

    Hess, Thomas M; Emery, Lisa; Queen, Tara L

    2009-06-01

    Previous research has demonstrated that older adults' memory performance is adversely affected by the explicit activation of negative stereotypes about aging. In this study, we examined the impact of stereotype threat on recognition memory, with specific interest in (a) the generalizability of previously observed effects, (b) the subjective experience of memory, and (c) the moderating effects of task demands. Older participants subjected to threat performed worse than did those in a nonthreat condition but only when performance constraints were high (i.e., memory decisions had to be made within a limited time frame). This effect was reflected in the subjective experience of memory, with participants in this condition having a lower ratio of "remember" to "know" responses. The absence of threat effects when constraints were minimal provides important boundary information regarding stereotype influences on memory performance.

  6. Is Performance in Task-Cuing Experiments Mediated by Task Set Selection or Associative Compound Retrieval?

    Science.gov (United States)

    Forrest, Charlotte L. D.; Monsell, Stephen; McLaren, Ian P. L.

    2014-01-01

    Task-cuing experiments are usually intended to explore control of task set. But when small stimulus sets are used, they plausibly afford learning of the response associated with a combination of cue and stimulus, without reference to tasks. In 3 experiments we presented the typical trials of a task-cuing experiment: a cue (colored shape) followed,…

  7. The Effect of a Workload-Preview on Task-Prioritization and Task-Performance

    Science.gov (United States)

    Minotra, Dev

    2012-01-01

    With increased volume and sophistication of cyber attacks in recent years, maintaining situation awareness and effective task-prioritization strategy is critical to the task of cybersecurity analysts. However, high levels of mental-workload associated with the task of cybersecurity analyst's limits their ability to prioritize tasks.…

  8. Computerized assessment of sustained attention: interactive effects of task demand, noise, and anxiety.

    Science.gov (United States)

    Ballard, J C

    1996-12-01

    In a sample of 163 college undergraduates, the effects of task demand, noise, and anxiety on Continuous Performance Test (CPT) errors were evaluated with multiple regression and multivariate analysis of variance. Results indicated significantly more omission errors on the difficult task. Complex interaction effects of noise and self-reported anxiety yielded more omissions in quiet intermittent white noise, particularly for high-anxious subjects performing the difficult task. Anxiety levels tended to increase from pretest to posttest, particularly for low-anxious subjects in the quiet, difficult-task condition, while a decrease was seen for high-anxious subjects in the loud, easy-task condition. Commission errors were unrelated to any predictor variables, suggesting that "attention" cannot be considered a unitary phenomenon. The variety of direct and interactive effects on vigilance performance underscore the need for clinicians to use a variety of measures to assess attentional skills, to avoid diagnosis of attention deficits on the basis of a single computerized task performance, and to rule out anxiety and other contributors to poor vigilance task performance.

  9. 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.

  10. Data from 617 Healthy Participants Performing the Iowa Gambling Task: A “Many Labs” Collaboration

    Directory of Open Access Journals (Sweden)

    Helen Steingroever

    2015-06-01

    Full Text Available This data pool (N = 617 comes from 10 independent studies assessing performance of healthy participants (i.e., no known neurological impairments on the Iowa gambling task (IGT—a task measuring decision making under uncertainty in an experimental context. Participants completed a computerized version of the IGT consisting of 95 – 150 trials. The data consist of the choices of each participant on each trial, and the resulting rewards and losses. The data are stored as .rdata, .csv, and .txt files, and can be reused to (1 analyze IGT performance of healthy participants; (2 create a “super control group”; or (3 facilitate model-comparison efforts.

  11. The effects of age, illustrations, and task variables on the performance of procedural assembly tasks.

    Science.gov (United States)

    Morrell, R W; Park, D C

    1993-09-01

    Older adults may be disadvantaged in the performance of procedural assembly tasks because of age-related declines in working memory operations. It was hypothesized that adding illustrations to instructional text may lessen age-related performance differences by minimizing processing demands on working memory in the elderly. In the present study, younger and older adults constructed a series of 3-dimensional objects from 3 types of instructions (text only, illustration only, or text and illustrations). Results indicated that instructions consisting of text and illustrations reduced errors in construction for both age groups compared with the other formats. Younger adults, however, outperformed older adults under all instructional format conditions. Measures of spatial and verbal working memory and text comprehension ability accounted for substantial age-related variance across the different format conditions but did not fully account for the age differences observed.

  12. Effects of task complexity on rhythmic reproduction performance in adults.

    Science.gov (United States)

    Iannarilli, Flora; Vannozzi, Giuseppe; Iosa, Marco; Pesce, Caterina; Capranica, Laura

    2013-02-01

    The aim of the present study was to investigate the effect of task complexity on the capability to reproduce rhythmic patterns. Sedentary musically illiterate individuals (age: 34.8±4.2 yrs; M±SD) were administered a rhythmic test including three rhythmic patterns to be reproduced by means of finger-tapping, foot-tapping and walking. For the quantification of subjects' ability in the reproduction of rhythmic patterns, qualitative and quantitative parameters were submitted to analysis. A stereophotogrammetric system was used to reconstruct and evaluate individual performances. The findings indicated a good internal stability of the rhythmic reproduction, suggesting that the present experimental design is suitable to discriminate the participants' rhythmic ability. Qualitative aspects of rhythmic reproduction (i.e., speed of execution and temporal ratios between events) varied as a function of the perceptual-motor requirements of the rhythmic reproduction task, with larger reproduction deviations in the walking task. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. 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

    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: (1) high-definition color television, (2) high-definition monochromatic television, (3) standard-resolution monochromatic television, and (4) standard-resolution stereoscopic monochromatic television. The stereo system accomplished stereoscopy by displaying two cross-polarized images, one reflected by a half-silvered mirror and one seen through the mirror. Observers wore a pair of glasses with cross-polarized lenses so that the left eye received only the view from the left camera and the right eye received only the view from the right camera

  14. 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....

  15. Helicopter Pilot Performance for Discrete-maneuver Flight Tasks

    Science.gov (United States)

    Heffley, R. K.; Bourne, S. M.; Hindson, W. S.

    1984-01-01

    This paper describes a current study of several basic helicopter flight maneuvers. The data base consists of in-flight measurements from instrumented helicopters using experienced pilots. The analysis technique is simple enough to apply without automatic data processing, and the results can be used to build quantitative matah models of the flight task and some aspects of the pilot control strategy. In addition to describing the performance measurement technqiue, some results are presented which define the aggressiveness and amplitude of maneuvering for several lateral maneuvers including turns and sidesteps.

  16. Behavior model for performance assessment

    International Nuclear Information System (INIS)

    Brown-VanHoozer, S. A.

    1999-01-01

    Every individual channels information differently based on their preference of the sensory modality or representational system (visual auditory or kinesthetic) we tend to favor most (our primary representational system (PRS)). Therefore, some of us access and store our information primarily visually first, some auditorily, and others kinesthetically (through feel and touch); which in turn establishes our information processing patterns and strategies and external to internal (and subsequently vice versa) experiential language representation. Because of the different ways we channel our information, each of us will respond differently to a task--the way we gather and process the external information (input), our response time (process), and the outcome (behavior). Traditional human models of decision making and response time focus on perception, cognitive and motor systems stimulated and influenced by the three sensory modalities, visual, auditory and kinesthetic. For us, these are the building blocks to knowing how someone is thinking. Being aware of what is taking place and how to ask questions is essential in assessing performance toward reducing human errors. Existing models give predications based on time values or response times for a particular event, and may be summed and averaged for a generalization of behavior(s). However, by our not establishing a basic understanding of the foundation of how the behavior was predicated through a decision making strategy process, predicative models are overall inefficient in their analysis of the means by which behavior was generated. What is seen is the end result

  17. Behavior model for performance assessment.

    Energy Technology Data Exchange (ETDEWEB)

    Borwn-VanHoozer, S. A.

    1999-07-23

    Every individual channels information differently based on their preference of the sensory modality or representational system (visual auditory or kinesthetic) we tend to favor most (our primary representational system (PRS)). Therefore, some of us access and store our information primarily visually first, some auditorily, and others kinesthetically (through feel and touch); which in turn establishes our information processing patterns and strategies and external to internal (and subsequently vice versa) experiential language representation. Because of the different ways we channel our information, each of us will respond differently to a task--the way we gather and process the external information (input), our response time (process), and the outcome (behavior). Traditional human models of decision making and response time focus on perception, cognitive and motor systems stimulated and influenced by the three sensory modalities, visual, auditory and kinesthetic. For us, these are the building blocks to knowing how someone is thinking. Being aware of what is taking place and how to ask questions is essential in assessing performance toward reducing human errors. Existing models give predications based on time values or response times for a particular event, and may be summed and averaged for a generalization of behavior(s). However, by our not establishing a basic understanding of the foundation of how the behavior was predicated through a decision making strategy process, predicative models are overall inefficient in their analysis of the means by which behavior was generated. What is seen is the end result.

  18. The Role of Self-Regulated Learning Capacities in Iranian EFL Undergraduates’ Argumentative Writing Task Performance

    Directory of Open Access Journals (Sweden)

    Ali Akbar Khomeijani Farahani

    2017-09-01

    Full Text Available The current study was an attempt to explore the relationship between Iranian EFL learners’ self-regulatory capacities and their argumentative writing task performance in order to analyze measures of complexity, accuracy, and fluency (CAF. To this end, 44 Iranian EFL undergraduates majoring in English literature at the University of Tehran were recruited based on convenience sampling to participate in this study. Employing a correlational design, the participants were required to perform an argumentative writing task and complete the Motivated Strategies for Learning Questionnaire designed by Pintrich, Smith, Garcia, and McKeachie (1991. Pearson product moment correlation indicated a significant relationship between self-regulated learning and writing task performance in relation to CAF measures. In addition, the results of multiple regression showed that resource management strategies and value component predicted 56.9% of grammatical accuracy of writing task. It was also shown that resource management strategies, value, and expectancy components predicted 56.5% of lexical complexity of writing task. Lastly, cognitive and metacognitive strategies, expectancy, and value components predicted 55.2% of the fluency of writing task. The findings of this study informs EFL writing pedagogy and English language teachers and syllabus designers  with regard to the benefits of applying self-regulatory strategies in teaching and assessing writing.

  19. Implementing the Science Assessment Standards: Developing and validating a set of laboratory assessment tasks in high school biology

    Science.gov (United States)

    Saha, Gouranga Chandra

    Very often a number of factors, especially time, space and money, deter many science educators from using inquiry-based, hands-on, laboratory practical tasks as alternative assessment instruments in science. A shortage of valid inquiry-based laboratory tasks for high school biology has been cited. Driven by this need, this study addressed the following three research questions: (1) How can laboratory-based performance tasks be designed and developed that are doable by students for whom they are designed/written? (2) Do student responses to the laboratory-based performance tasks validly represent at least some of the intended process skills that new biology learning goals want students to acquire? (3) Are the laboratory-based performance tasks psychometrically consistent as individual tasks and as a set? To answer these questions, three tasks were used from the six biology tasks initially designed and developed by an iterative process of trial testing. Analyses of data from 224 students showed that performance-based laboratory tasks that are doable by all students require careful and iterative process of development. Although the students demonstrated more skill in performing than planning and reasoning, their performances at the item level were very poor for some items. Possible reasons for the poor performances have been discussed and suggestions on how to remediate the deficiencies have been made. Empirical evidences for validity and reliability of the instrument have been presented both from the classical and the modern validity criteria point of view. Limitations of the study have been identified. Finally implications of the study and directions for further research have been discussed.

  20. 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.

  1. Attentional fluctuations in preschoolers: Direct and indirect relations with task accuracy, academic readiness, and school performance.

    Science.gov (United States)

    Isbell, Elif; Calkins, Susan D; Swingler, Margaret M; Leerkes, Esther M

    2018-03-01

    Attentional control fluctuates in the presence of internal and external distractors, wandering on and off a given task. The current study investigated individual differences in attentional fluctuations in 250 preschoolers. Attentional fluctuations were assessed via intra-individual variability in response time in a Go/No-Go task. Greater fluctuations in attentional control were linked to lower task accuracy. In addition, greater attentional fluctuations predicted lower performance in a task of cognitive flexibility, the Dimensional Change Card Sort task. Attentional fluctuations were also associated with laboratory measures of academic readiness in preschool, as assessed by the Applied Problems and Letter-Word Identification subscales of the Woodcock-Johnson III Tests of Achievement, which in turn predicted teacher reports of academic performance in first grade. Attentional fluctuations also had indirect associations with emergent math skills in preschool, via cognitive flexibility, as well as indirect associations with first-grade teacher reports of academic performance, via the relations between cognitive flexibility and emergent math skills in preschool. These results suggest that consistency is an important aspect of attentional control during early childhood. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. OLEM Performance Assessment Information

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset includes a variety of data sets that measure the performance of Office of Land and Emergency Management (OLEM) programs in support of the Office of the...

  3. Location versus task relevance: The impact of differing internal focus of attention instructions on motor performance.

    Science.gov (United States)

    Pelleck, Valerie; Passmore, Steven R

    2017-05-01

    Impaired performance while executing a motor task is attributed to a disruption of normal automatic processes when an internal focus of attention is used. What remains unclear is whether the specificity of internally focused task instructions may impact task performance. The present study assessed the implications of changing the attentional focus of novice and skilled golfers by measuring behavioural, neurophysiological and kinematic changes during a golf putting task. Over six blocks of ten putting trials each, attention was directed either externally (towards the target) or internally in one of two ways: 1) proximal (keeping the elbows extended and the hands gripping the putter); or 2) distal (keeping the weight evenly distributed between both legs) to the critical elements of the task. Results provided evidence that when novice participants use an internal focus of attention more closely associated with task performance that their: 1) execution; 2) accuracy; 3) variability of surface electromyography (sEMG) activity; and 4) kinematics of the putter movement are all adversely affected. Skilled golfers are much more resilient to changes in attentional focus, while all participants interpret a distal internal focus of attention similar to an external focus. All participants produced decreased activity in the muscle (tibialis anterior) associated with the distal (less task relevant) focus of attention even when the "internal" focus was on the lower extremity. Our results provide evidence that the skill level of the participant and the distance of the internal focus of attention from the key elements of a motor skill directly impact the execution, muscle activity, and movement kinematics associated with skilled motor task performance. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Associations between physical function, dual-task performance and cognition in patients with mild Alzheimer's disease.

    Science.gov (United States)

    Sobol, Nanna Aue; Hoffmann, Kristine; Vogel, Asmus; Lolk, Annette; Gottrup, Hanne; Høgh, Peter; Hasselbalch, Steen G; Beyer, Nina

    2016-11-01

    Alzheimer's disease (AD) causes a gradual decline in cognition, limitations of dual-tasking and physical function leading to total dependence. Hence, information about the interaction between physical function, dual-task performance and cognition may lead to new treatment strategies with the purpose of preserving function and quality of life. The objective of this study was to investigate the associations between physical function, dual-task performance and cognition in community-dwelling patients with mild AD. Baseline results from 185 participants (50-90 years old) in the single blinded multicenter RCT 'ADEX' (Alzheimer's disease: the effect of physical exercise) were used. Assessments included tests of physical function: 400-m walk test, 10-m walk test, Timed Up and Go test and 30-s chair stand test; dual-task performance, i.e., 10-m walk while counting backwards from 50 or naming the months backwards; and cognition, i.e., Mini Mental State Examination, Symbol Digit Modalities Test, the Stroop Color and Word Test, and Lexical verbal fluency test. Results in the 30-s chair stand test correlated significantly with all tests of cognition (r = .208-.242) while the other physical function tests only randomly correlated with tests of cognition. Results in the dual-task counting backwards correlated significantly with results in all tests of cognition (r = .259-.388), which accounted for 7%-15% of the variation indicating that a faster time to complete dual-task performance was associated with better cognitive performance. The evidence of the associations between physical function, dual-task performance and cognition is important when creating new rehabilitation interventions to patients with mild AD.

  5. The cortisol awakening response is associated with performance of a serial sequence reaction time task.

    Science.gov (United States)

    Hodyl, Nicolette A; Schneider, Luke; Vallence, Ann-Maree; Clow, Angela; Ridding, Michael C; Pitcher, Julia B

    2016-02-01

    There is emerging evidence of a relationship between the cortisol awakening response (CAR) and the neural mechanisms underlying learning and memory. The aim of this study was to determine whether the CAR is associated with acquisition, retention and overnight consolidation or improvement of a serial sequence reaction time task. Salivary samples were collected at 0, 15, 30 and 45 min after awakening in 39 healthy adults on 2 consecutive days. The serial sequence reaction time task was repeated each afternoon. Participants completed the perceived stress scale and provided salivary samples prior to testing for cortisol assessment. While the magnitude of the CAR (Z score) was not associated with either baseline performance or the timed improvement during task acquisition of the serial sequence task, a positive correlation was observed with reaction times during the stable performance phase on day 1 (r=0.373, p=0.019). Residuals derived from the relationship between baseline and stable phase reaction times on day 1 were used as a surrogate for the degree of learning: these residuals were also correlated with the CAR mean increase on day 1 (r=0.357, p=0.048). Task performance on day 2 was not associated with the CAR obtained on this same day. No association was observed between the perceived stress score, cortisol at testing or task performance. These data indicate that a smaller CAR in healthy adults is associated with a greater degree of learning and faster performance of a serial sequence reaction time task. These results support recognition of the CAR as an important factor contributing to cognitive performance throughout the day. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Simply Performance Assessment

    Science.gov (United States)

    McLaughlin, Cheryl A.; McLaughlin, Felecia C.; Pringle, Rose M.

    2013-01-01

    This article presents the experiences of Miss Felecia McLaughlin, a fourth-grade teacher from the island of Jamaica who used the model proposed by Bass et al. (2009) to assess conceptual understanding of four of the six types of simple machines while encouraging collaboration through the creation of learning teams. Students had an opportunity to…

  7. CHARACTERIZATION OF THE EFFECTS OF INHALED PERCHLOROETHYLENE ON SUSTAINED ATTENTION IN RATS PERFORMING A VISUAL SIGNAL DETECTION TASK

    Science.gov (United States)

    The aliphatic hydrocarbon perchloroethyelene (PCE) has been associated with neurobehavioral dysfunction including reduced attention in humans. The current study sought to assess the effects of inhaled PCE on sustained attention in rats performing a visual signal detection task (S...

  8. Dual-Task Performance: Influence of Frailty, Level of Physical Activity, and Cognition.

    Science.gov (United States)

    Giusti Rossi, Paulo; Pires de Andrade, Larissa; Hotta Ansai, Juliana; Silva Farche, Ana Claudia; Carnaz, Leticia; Dalpubel, Daniela; Ferriolli, Eduardo; Assis Carvalho Vale, Francisco; de Medeiros Takahashi, Anielle Cristhine

    2018-03-08

    Cognition and level of physical activity have been associated with frailty syndrome. The development of tools that assess deficits related to physical and cognitive frailties simultaneously are of common interest. However, little is known about how much these aspects influence the performance of dual-task tests. Our aims were (a) to verify the influence of frailty syndrome and objectively measured physical activity and cognition on the Timed Up and Go (TUG) test and Timed Up and Go associated with dual-task (TUG-DT) performances; and (b) to compare TUG and TUG-DT performances between older adults who develop frailty syndrome. Sixty-four community-dwelling older adults were divided into frail, prefrail, and nonfrail groups, according to frailty phenotype. Assessments included anamnesis, screening of frailty syndrome, cognitive assessment (Addenbrooke's cognitive examination), placement of a triaxial accelerometer to assess level of physical activity, and TUG and TUG-DT (TUG associated with a motor-cognitive task of calling a phone number) performances. After 7 days, the accelerometer was removed. A multiple linear regression was applied to identify which independent variables could explain performances in the TUG and TUG-DT. Subsequently, the analysis of covariance test, adjusted for age, cognition, and level of physical activity covariates, was used to compare test performances. There were no differences in cognition between groups. Significant differences in the level of physical activity were found in the frail group. Compared with the frail group, the nonfrail group required less time and fewer steps to complete the TUG. Regarding the TUG-DT, cognition and age influenced the time spent and number of steps, respectively; however, no differences were found between groups. Frail older adults presented worse performance in the TUG when compared with nonfrail older adults. The dual-task test does not differentiate older adults with frailty syndrome, regardless of

  9. Pilot task-based assessment of noise levels among firefighters.

    Science.gov (United States)

    Neitzel, Rl; Hong, O; Quinlan, P; Hulea, R

    2013-11-01

    Over one million American firefighters are routinely exposed to various occupational hazards agents. While efforts have been made to identify and reduce some causes of injuries and illnesses among firefighters, relatively little has been done to evaluate and understand occupational noise exposures in this group. The purpose of this pilot study was to apply a task-based noise exposure assessment methodology to firefighting operations to evaluate potential noise exposure sources, and to use collected task-based noise levels to create noise exposure estimates for evaluation of risk of noise-induced hearing loss by comparison to the 8-hr and 24-hr recommended exposure limits (RELs) for noise of 85 and 80.3 dBA, respectively. Task-based noise exposures (n=100 measurements) were measured in three different fire departments (a rural department in Southeast Michigan and suburban and urban departments in Northern California). These levels were then combined with time-at-task information collected from firefighters to estimate 8-hr noise exposures for the rural and suburban fire departments (n=6 estimates for each department). Data from 24-hr dosimetry measurements and crude self-reported activity categories from the urban fire department (n=4 measurements) were used to create 24-hr exposure estimates to evaluate the bias associated with the task-based estimates. Task-based noise levels were found to range from 82-109 dBA, with the highest levels resulting from use of saws and pneumatic chisels. Some short (e.g., 30 min) sequences of common tasks were found to result in nearly an entire allowable daily exposure. The majority of estimated 8-hr and 24-hr exposures exceeded the relevant recommended exposure limit. Predicted 24-hr exposures showed substantial imprecision in some cases, suggesting the need for increased task specificity. The results indicate potential for overexposure to noise from a variety of firefighting tasks and equipment, and suggest a need for further

  10. Functional MRI assessment of hemispheric language dominance with using a lexical decision task

    International Nuclear Information System (INIS)

    Ryoo, Jae Wook; Choi, Dae Seob; Cho, Jae Min; Park, Eui Dong; You, Jin Jong; Na, Dong Gyu; Kim, Sam Soo; Cha, Sang Hoon

    2005-01-01

    We wanted to compare the fMRIs (functional magnetic resonance images) obtained during a lexical decision task and also during a word generation task, and we wanted to evaluate the usefulness of using a lexical decision task for the visualization of the brain language area and for the determination of language dominance. Sixteen patients (9 women and 7 men) who had had undergone the Wada test were included in our study. All the patients were left dominant for language, as tested for on the Wada test. The functional maps of the brain language area were obtained in all the subjects during the performance of a lexical decision task and also during the performance of a word generation task. The MR examinations were performed with a 1.5 T scanner and with using the EPI BOLD technique. We used the SPM program for the postprocessing of the images. The threshold for significance was set at ρ <0.001 or ρ <0.01. A lateralization index was calculated from the number of activated pixels in each hemispheric region (the whole hemisphere, the frontal lobe and the temporoparietal lobe), and the hemispheric language dominance was assessed by the lateralization index; the results were then compared with those results of the Wada test. The differences for the lateralization of the language area were analyzed with regard to the stimulation tasks and the regions used for the calculation of the lateralization indices. The number of activated pixels during the lexical decision task was significantly smaller than that of the word generation task. The language dominance based on the activated signals in each hemisphere, was consistent with the results of the Wada test for the word generation tasks in all the subjects. On the lexical decision task, the language dominance, as determined by the activated signals in each hemisphere and the temporoparietal lobe, correlated for 94% of the patients. The mean values of the lateralization index for the lexical decision task were higher than those

  11. Functional MRI assessment of hemispheric language dominance with using a lexical decision task

    Energy Technology Data Exchange (ETDEWEB)

    Ryoo, Jae Wook; Choi, Dae Seob; Cho, Jae Min; Park, Eui Dong; You, Jin Jong [Gyeongsang National University College of Medicine, Jinju (Korea, Republic of); Na, Dong Gyu [Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of); Cha, Sang Hoon [Chungbuk National University College of Medicine, Cheonju (Korea, Republic of)

    2005-07-15

    We wanted to compare the fMRIs (functional magnetic resonance images) obtained during a lexical decision task and also during a word generation task, and we wanted to evaluate the usefulness of using a lexical decision task for the visualization of the brain language area and for the determination of language dominance. Sixteen patients (9 women and 7 men) who had had undergone the Wada test were included in our study. All the patients were left dominant for language, as tested for on the Wada test. The functional maps of the brain language area were obtained in all the subjects during the performance of a lexical decision task and also during the performance of a word generation task. The MR examinations were performed with a 1.5 T scanner and with using the EPI BOLD technique. We used the SPM program for the postprocessing of the images. The threshold for significance was set at {rho} <0.001 or {rho} <0.01. A lateralization index was calculated from the number of activated pixels in each hemispheric region (the whole hemisphere, the frontal lobe and the temporoparietal lobe), and the hemispheric language dominance was assessed by the lateralization index; the results were then compared with those results of the Wada test. The differences for the lateralization of the language area were analyzed with regard to the stimulation tasks and the regions used for the calculation of the lateralization indices. The number of activated pixels during the lexical decision task was significantly smaller than that of the word generation task. The language dominance based on the activated signals in each hemisphere, was consistent with the results of the Wada test for the word generation tasks in all the subjects. On the lexical decision task, the language dominance, as determined by the activated signals in each hemisphere and the temporoparietal lobe, correlated for 94% of the patients. The mean values of the lateralization index for the lexical decision task were higher than

  12. The Regulation of Task Performance: A Trans-disciplinary Review

    Directory of Open Access Journals (Sweden)

    Ian eClark

    2016-01-01

    Full Text Available Definitions of meta-cognition typically have two components: (1 knowledge about one’s own cognitive functioning; and, (2 control over one’s own cognitive activities. Since Flavell and his colleagues provided the empirical foundation on which to build studies of metacognition and the autonoetic (self knowledge required for effective learning, the intervening years have seen the extensive dissemination of theoretical and empirical research on metacognition, which now encompasses a variety of issues and domains including educational psychology and neuroscience. Nevertheless, the psychological and neural underpinnings of metacognitive predictions and reflections that determine subsequent regulation of task performance remain ill understood. This article provides an outline of metacognition in the science of education with evidence drawn from neuroimaging, psycho-physiological, and psychological literature. We will rigorously explore research that addresses the pivotal role of the prefrontal cortex (PFC in controlling the metacognitive processes that underpin the self-regulated learning (SRL strategies learners employ to regulate task performance. The article delineates what those strategies are, and how the learning environment can facilitate or frustrate strategy use by influencing learners’ self-efficacy.

  13. EFFECTIVE INDICES FOR MONITORING MENTAL WORKLOAD WHILE PERFORMING MULTIPLE TASKS.

    Science.gov (United States)

    Hsu, Bin-Wei; Wang, Mao-Jiun J; Chen, Chi-Yuan; Chen, Fang

    2015-08-01

    This study identified several physiological indices that can accurately monitor mental workload while participants performed multiple tasks with the strategy of maintaining stable performance and maximizing accuracy. Thirty male participants completed three 10-min. simulated multitasks: MATB (Multi-Attribute Task Battery) with three workload levels. Twenty-five commonly used mental workload measures were collected, including heart rate, 12 HRV (heart rate variability), 10 EEG (electroencephalography) indices (α, β, θ, α/θ, θ/β from O1-O2 and F4-C4), and two subjective measures. Analyses of index sensitivity showed that two EEG indices, θ and α/θ (F4-C4), one time-domain HRV-SDNN (standard deviation of inter-beat intervals), and four frequency-domain HRV: VLF (very low frequency), LF (low frequency), %HF (percentage of high frequency), and LF/HF were sensitive to differentiate high workload. EEG α/θ (F4-C4) and LF/HF were most effective for monitoring high mental workload. LF/HF showed the highest correlations with other physiological indices. EEG α/θ (F4-C4) showed strong correlations with subjective measures across different mental workload levels. Operation strategy would affect the sensitivity of EEG α (F4-C4) and HF.

  14. The Regulation of Task Performance: A Trans-Disciplinary Review

    Science.gov (United States)

    Clark, Ian; Dumas, Guillaume

    2016-01-01

    Definitions of meta-cognition typically have two components: (1) knowledge about one's own cognitive functioning; and, (2) control over one's own cognitive activities. Since Flavell and his colleagues provided the empirical foundation on which to build studies of meta-cognition and the autonoetic (self) knowledge required for effective learning, the intervening years have seen the extensive dissemination of theoretical and empirical research on meta-cognition, which now encompasses a variety of issues and domains including educational psychology and neuroscience. Nevertheless, the psychological and neural underpinnings of meta-cognitive predictions and reflections that determine subsequent regulation of task performance remain ill understood. This article provides an outline of meta-cognition in the science of education with evidence drawn from neuroimaging, psycho-physiological, and psychological literature. We will rigorously explore research that addresses the pivotal role of the prefrontal cortex (PFC) in controlling the meta-cognitive processes that underpin the self-regulated learning (SRL) strategies learners employ to regulate task performance. The article delineates what those strategies are, and how the learning environment can facilitate or frustrate strategy use by influencing learners' self-efficacy. PMID:26779050

  15. 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.

  16. Motor planning flexibly optimizes performance under uncertainty about task goals.

    Science.gov (United States)

    Wong, Aaron L; Haith, Adrian M

    2017-03-03

    In an environment full of potential goals, how does the brain determine which movement to execute? Existing theories posit that the motor system prepares for all potential goals by generating several motor plans in parallel. One major line of evidence for such theories is that presenting two competing goals often results in a movement intermediate between them. These intermediate movements are thought to reflect an unintentional averaging of the competing plans. However, normative theories suggest instead that intermediate movements might actually be deliberate, generated because they improve task performance over a random guessing strategy. To test this hypothesis, we vary the benefit of making an intermediate movement by changing movement speed. We find that participants generate intermediate movements only at (slower) speeds where they measurably improve performance. Our findings support the normative view that the motor system selects only a single, flexible motor plan, optimized for uncertain goals.

  17. Total System Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Yong Soo; Kang, Chul Hyung; Lee, Youn Myoung; Han, Ji Woong; Choi, Jong Won; Hahn, Pil Soo; Park, Jeong Hwa; Jeong, Mi Seon

    2007-06-15

    Based on the KAERI FEP list developed through the previous studies, the KAERI FEP Encyclopedia has been developed. Current version is 1.0 which includes all relevant FEPs to compose of two references and all alternative scenarios. Many interaction FEPs between scenario defining FEP(SDF) are created throughout the study. FEPs are classified into many Integrated FEP(IFEP) which eventually become the elements of the RES matrix. The FEAS program one of the component of the KAERI's CYPRUS information system is added to develop the FEP, RES, AC, AMF and finally scenarios. It assists to create transparent way to deal with assessment from the stage of the planning of the R and D to the final stage of the external audit and regulatory body review. Even though MASCOT-K and compartment analysis codes such as AMBER, GoldSim and Ecolego are excellent for TSPA they by in heritage possess a certain limitation especially to identify a proper migration cross sectional area when a relatively big component intersects with a tiny one such as a fracture. It is truly 3D phenomena in nature. MDPSA code is developed which is expected to overcome limitations in compartment models while successfully deals with natural disruptive events. The R and D target for the TSPA is to develop the sufficient scenarios and their variation cases to understand the safety of KRS in every possible aspect. For this, reference scenarios, alternative scenarios covering engineered barrier failure and natural events are developed and assessed respectively for around 100 cases. The stylized template to assess the Korean reference biosphere is developed using the AMBER. Three critical groups, agricultural, freshwater and marine water fishing groups are identified to assess the DCF following the guidelines of ICRP. Based on the QA principles of T2R3, the web based QA system is developed using the procedures in the USNRC 10CFR50 Appendix B. The QA system is combined with the PAID and FEAS to create the comprehensive

  18. Total System Performance Assessment

    International Nuclear Information System (INIS)

    Hwang, Yong Soo; Kang, Chul Hyung; Lee, Youn Myoung; Han, Ji Woong; Choi, Jong Won; Hahn, Pil Soo; Park, Jeong Hwa; Jeong, Mi Seon

    2007-06-01

    Based on the KAERI FEP list developed through the previous studies, the KAERI FEP Encyclopedia has been developed. Current version is 1.0 which includes all relevant FEPs to compose of two references and all alternative scenarios. Many interaction FEPs between scenario defining FEP(SDF) are created throughout the study. FEPs are classified into many Integrated FEP(IFEP) which eventually become the elements of the RES matrix. The FEAS program one of the component of the KAERI's CYPRUS information system is added to develop the FEP, RES, AC, AMF and finally scenarios. It assists to create transparent way to deal with assessment from the stage of the planning of the R and D to the final stage of the external audit and regulatory body review. Even though MASCOT-K and compartment analysis codes such as AMBER, GoldSim and Ecolego are excellent for TSPA they by in heritage possess a certain limitation especially to identify a proper migration cross sectional area when a relatively big component intersects with a tiny one such as a fracture. It is truly 3D phenomena in nature. MDPSA code is developed which is expected to overcome limitations in compartment models while successfully deals with natural disruptive events. The R and D target for the TSPA is to develop the sufficient scenarios and their variation cases to understand the safety of KRS in every possible aspect. For this, reference scenarios, alternative scenarios covering engineered barrier failure and natural events are developed and assessed respectively for around 100 cases. The stylized template to assess the Korean reference biosphere is developed using the AMBER. Three critical groups, agricultural, freshwater and marine water fishing groups are identified to assess the DCF following the guidelines of ICRP. Based on the QA principles of T2R3, the web based QA system is developed using the procedures in the USNRC 10CFR50 Appendix B. The QA system is combined with the PAID and FEAS to create the comprehensive

  19. Total System Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Yong Soo; Kang, Chul Hyung; Lee, Youn Myoung; Han, Ji Woong; Choi, Jong Won; Hahn, Pil Soo; Park, Jeong Hwa; Jeong, Mi Seon

    2007-06-15

    Based on the KAERI FEP list developed through the previous studies, the KAERI FEP Encyclopedia has been developed. Current version is 1.0 which includes all relevant FEPs to compose of two references and all alternative scenarios. Many interaction FEPs between scenario defining FEP(SDF) are created throughout the study. FEPs are classified into many Integrated FEP(IFEP) which eventually become the elements of the RES matrix. The FEAS program one of the component of the KAERI's CYPRUS information system is added to develop the FEP, RES, AC, AMF and finally scenarios. It assists to create transparent way to deal with assessment from the stage of the planning of the R and D to the final stage of the external audit and regulatory body review. Even though MASCOT-K and compartment analysis codes such as AMBER, GoldSim and Ecolego are excellent for TSPA they by in heritage possess a certain limitation especially to identify a proper migration cross sectional area when a relatively big component intersects with a tiny one such as a fracture. It is truly 3D phenomena in nature. MDPSA code is developed which is expected to overcome limitations in compartment models while successfully deals with natural disruptive events. The R and D target for the TSPA is to develop the sufficient scenarios and their variation cases to understand the safety of KRS in every possible aspect. For this, reference scenarios, alternative scenarios covering engineered barrier failure and natural events are developed and assessed respectively for around 100 cases. The stylized template to assess the Korean reference biosphere is developed using the AMBER. Three critical groups, agricultural, freshwater and marine water fishing groups are identified to assess the DCF following the guidelines of ICRP. Based on the QA principles of T2R3, the web based QA system is developed using the procedures in the USNRC 10CFR50 Appendix B. The QA system is combined with the PAID and FEAS to create the

  20. Effects of Dual-Task Management and Resistance Training on Gait Performance in Older Individuals: A Randomized Controlled Trial

    Science.gov (United States)

    Wollesen, Bettina; Mattes, Klaus; Schulz, Sören; Bischoff, Laura L.; Seydell, L.; Bell, Jeffrey W.; von Duvillard, Serge P.

    2017-01-01

    Background: Dual-task (DT) training is a well-accepted modality for fall prevention in older adults. DT training should include task-managing strategies such as task switching or task prioritization to improve gait performance under DT conditions. Methods: We conducted a randomized controlled trial to evaluate a balance and task managing training (BDT group) in gait performance compared to a single task (ST) strength and resistance training and a control group, which received no training. A total of 78 older individuals (72.0 ± 4.9 years) participated in this study. The DT group performed task managing training incorporating balance and coordination tasks while the ST group performed resistance training only. Training consisted of 12 weekly sessions, 60 min each, for 12 weeks. We assessed the effects of ST and BDT training on walking performance under ST and DT conditions in independent living elderly adults. ST and DT walking (visual verbal Stroop task) were measured utilizing a treadmill at self-selected walking speed (mean for all groups: 4.4 ± 1 km h-1). Specific gait variables, cognitive performance, and fear of falling were compared between all groups. >Results: Training improved gait performance for step length (p changes in cognitive performance. Both interventions reduced fear of falling (p management strategies into balance and strength training in our population revealed a promising modality to prevent falls in older individuals. Trial registration: German register of clinical trials DRKS00012382. PMID:29326581

  1. The effect of divided attention on novices and experts in laparoscopic task performance.

    Science.gov (United States)

    Ghazanfar, Mudassar Ali; Cook, Malcolm; Tang, Benjie; Tait, Iain; Alijani, Afshin

    2015-03-01

    Attention is important for the skilful execution of surgery. The surgeon's attention during surgery is divided between surgery and outside distractions. The effect of this divided attention has not been well studied previously. We aimed to compare the effect of dividing attention of novices and experts on a laparoscopic task performance. Following ethical approval, 25 novices and 9 expert surgeons performed a standardised peg transfer task in a laboratory setup under three randomly assigned conditions: silent as control condition and two standardised auditory distracting tasks requiring response (easy and difficult) as study conditions. Human reliability assessment was used for surgical task analysis. Primary outcome measures were correct auditory responses, task time, number of surgical errors and instrument movements. Secondary outcome measures included error rate, error probability and hand specific differences. Non-parametric statistics were used for data analysis. 21109 movements and 9036 total errors were analysed. Novices had increased mean task completion time (seconds) (171 ± 44SD vs. 149 ± 34, p 0.05). Divided attention conditions in theatre environment require careful consideration during surgical training as the junior surgeons are less able to focus their attention during these conditions.

  2. Introduction to radiological performance assessment

    International Nuclear Information System (INIS)

    Moss, G.

    1995-02-01

    A radiological performance assessment is conducted to provide reasonable assurance that performance objectives for low-level radioactive waste (LLW) disposal will be met. Beginning in the early stages of development, a radiological performance assessment continues through the operational phase, and is instrumental in the postclosure of the facility. Fundamental differences exist in the regulation of commercial and defense LLW, but the radiological performance assessment process is essentially the same for both. The purpose of this document is to describe that process in a concise and straightforward manner. This document focuses on radiological performance assessment as it pertains to commercial LLW disposal, but is applicable to US Department of Energy sites as well. Included are discussions on performance objectives, site characterization, and how a performance assessment is conducted. A case study is used to illustrate how the process works as a whole. A bibliography is provided to assist in locating additional information

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

    Science.gov (United States)

    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.

  4. The process of performance assessment

    International Nuclear Information System (INIS)

    King, C.M.; Halford, D.K.

    1986-01-01

    An introductory review of the subject of ''Performance Assessment'' will be presented. Emphasis will be placed on the process of performance assessment from the standpoint of defining the process. Performance assessment, from evolving experience at DOE sites, has short-term and long-term subprograms, the components of which will be discussed. The role of mathematical modeling in performance assessment will be addressed including the pros and cons of current approaches. Finally, the ''system/site/technology'' issues as the focal point of this symposium will be reviewed

  5. Performance assessment of gamma cameras. Part 1

    International Nuclear Information System (INIS)

    Elliot, A.T.; Short, M.D.; Potter, D.C.; Barnes, K.J.

    1980-11-01

    The Dept. of Health and Social Security and the Scottish Home and Health Dept. has sponsored a programme of measurements of the important performance characteristics of 15 leading types of gamma cameras providing a routine radionuclide imaging service in hospitals throughout the UK. Measurements have been made of intrinsic resolution, system resolution, non-uniformity, spatial distortion, count rate performance, sensitivity, energy resolution and shield leakage. The main aim of this performance assessment was to provide sound information to the NHS to ease the task of those responsible for the purchase of gamma cameras. (U.K.)

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

    Science.gov (United States)

    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.

  7. Technology Performance Level Assessment Methodology.

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Jesse D.; Bull, Diana L; Malins, Robert Joseph; Costello, Ronan Patrick; Aurelien Babarit; Kim Nielsen; Claudio Bittencourt Ferreira; Ben Kennedy; Kathryn Dykes; Jochem Weber

    2017-04-01

    The technology performance level (TPL) assessments can be applied at all technology development stages and associated technology readiness levels (TRLs). Even, and particularly, at low TRLs the TPL assessment is very effective as it, holistically, considers a wide range of WEC attributes that determine the techno-economic performance potential of the WEC farm when fully developed for commercial operation. The TPL assessment also highlights potential showstoppers at the earliest possible stage of the WEC technology development. Hence, the TPL assessment identifies the technology independent “performance requirements.” In order to achieve a successful solution, the entirety of the performance requirements within the TPL must be considered because, in the end, all the stakeholder needs must be achieved. The basis for performing a TPL assessment comes from the information provided in a dedicated format, the Technical Submission Form (TSF). The TSF requests information from the WEC developer that is required to answer the questions posed in the TPL assessment document.

  8. 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...

  9. The effect of the sensitivity of the BAS and BAS motivational systems on performance in stroke rehabilitation tasks

    Directory of Open Access Journals (Sweden)

    Maja Milavec

    2012-03-01

    Full Text Available Stroke rehabilitation programs are often too short and not intensive enough, possibly due to a lack of patient motivation. This study examined whether the patient's mood, task success and psychophysiological responses are affected by the sensitivity of two motivational systems: the Behavioral Activation System (BAS and the Behavioral Inhibition System (BIS. 22 subacute stroke patients participated in the study. They performed an easier and harder version of a motor rehabilition task as well as the Stroop task. The sensitivities of the two motivational systems were measured using the BIS/BAS scale. Additionally, psychophysiological measurements (heart rate, skin conductance, respiration and skin temperature were taken and the Self-Assessment Manikin was used to measure self-reported valence and arousal. Results showed that valence and arousal are not significantly correlated with BIS/BAS subscales during the rehabilitation task. A negative correlation between valence and the BAS subscales was found in the Stroop task. Results also confirmed the initial hypothesis that the BAS would be correlated with task performance during the rehabilitation task while the BIS would be negatively correlated with task performance during the Stroop task. Only partial confirmation was found for the hypothesis that tasks that include a reward would affect heart rate in subjects with a sensitive BAS while tasks without a reward would affect skin conductance in subjects with a sensitive BIS. In both versions of the rehabilitation task, which includes a reward, the BAS reward subscale was negatively correlated with mean skin temperature. In the harder rehabilitation task, the BAS reward responsiveness subscale was positively correlated with mean heart rate. In the Stroop task, which has no reward, the BIS scale was positively correlated with mean heart rate. The BAS subscale was also negatively correlated with the RMSSD measure of heart rate variability. The results of

  10. Brain biomarkers based assessment of cognitive workload in pilots under various task demands.

    Science.gov (United States)

    Gentili, Rodolphe J; Rietschel, Jeremy C; Jaquess, Kyle J; Lo, Li-Chuan; Prevost, Michael; Miller, Matt W; Mohler, Jessica M; Oh, Hyuk; Tan, Ying Ying; Hatfield, Bradley D

    2014-01-01

    Cognitive workload is an important element of cognitive-motor performance such as that exhibited during the piloting of an aircraft. Namely, an increase in task demands on the pilot can elevate cognitive information processing and, thus, the risk of human error. As such, there is a need to develop methods that reliably assess mental workload in pilots within operational settings. The present study contributes to this research goal by identifying physiological and brain biomarkers of cognitive workload and attentional reserve during a simulated aircraft piloting task under three progressive levels of challenge. A newly developed experimental method was employed by which electroencephalography (EEG) was acquired via a dry (i.e., gel-free sensors) system using few scalp sites. Self-reported responses to surveys and piloting performance indicators were analyzed. The findings revealed that as the challenge (task demands) increased, the perceived mental load increased, attentional reserve was attenuated, and task performance decreased. Such an increase in task demands was also reflected by changes in heart rate variability (HRV), as well as in the amplitude of the P300 component of event-related potentials to auditory probes, and in the spectral power of specific EEG frequency bands. This work provides a first step towards a long-term goal to develop a composite system of biomarkers for real-time cognitive workload assessment and state assessment of pilots in operational settings.

  11. Boon and Bane of Being Sure: The Effect of Performance Certainty and Expectancy on Task Performance

    Science.gov (United States)

    Schindler, Simon; Reinhard, Marc-André; Dickhäuser, Oliver

    2016-01-01

    Previous research has suggested certainty to be an important factor when investigating effects of level of expectancies on future behavior. With the present study, we addressed the interplay of expectancy certainty and level of expectancies regarding task performance. We assumed that certain performance expectancies provide a better basis for the…

  12. 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…

  13. Underground Test Area Subproject Phase I Data Analysis Task. Volume VIII - Risk Assessment Documentation Package

    Energy Technology Data Exchange (ETDEWEB)

    None

    1996-12-01

    Volume VIII of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the risk assessment documentation. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.

  14. Dehydration: physiology, assessment, and performance effects.

    Science.gov (United States)

    Cheuvront, Samuel N; Kenefick, Robert W

    2014-01-01

    This article provides a comprehensive review of dehydration assessment and presents a unique evaluation of the dehydration and performance literature. The importance of osmolality and volume are emphasized when discussing the physiology, assessment, and performance effects of dehydration. The underappreciated physiologic distinction between a loss of hypo-osmotic body water (intracellular dehydration) and an iso-osmotic loss of body water (extracellular dehydration) is presented and argued as the single most essential aspect of dehydration assessment. The importance of diagnostic and biological variation analyses to dehydration assessment methods is reviewed and their use in gauging the true potential of any dehydration assessment method highlighted. The necessity for establishing proper baselines is discussed, as is the magnitude of dehydration required to elicit reliable and detectable osmotic or volume-mediated compensatory physiologic responses. The discussion of physiologic responses further helps inform and explain our analysis of the literature suggesting a ≥ 2% dehydration threshold for impaired endurance exercise performance mediated by volume loss. In contrast, no clear threshold or plausible mechanism(s) support the marginal, but potentially important, impairment in strength, and power observed with dehydration. Similarly, the potential for dehydration to impair cognition appears small and related primarily to distraction or discomfort. The impact of dehydration on any particular sport skill or task is therefore likely dependent upon the makeup of the task itself (e.g., endurance, strength, cognitive, and motor skill). © 2014 American Physiological Society.

  15. SPI Project Criticality Task Force initial review and assessment

    International Nuclear Information System (INIS)

    McKinley, K.B.; Cannon, J.W.; Marsden, R.S.; Worle, H.A.

    1980-03-01

    The Slagging Pyrolysis Incinerator (SPI) Facility is being developed to process transuranic waste stored and buried at the Idaho National Engineering Laboratory (INEL) into a chemically inert, physically stable, basalt-like residue acceptable for a Federal Repository. A task force was established by the SPI Project Division to review and assess all aspects of criticality safety for the SPI Facility. This document presents the initial review, evaluations, and recommendations of the task force and includes the following: background information on waste characterization, and criticality control approaches and philosophies, a description of the SPI Facility Waste Processing Building, a review and assessment of potentially relevant codes and regulations; a review and assessment of the present state of criticality and assaying/monitoring studies, and recommendations for changes in and additions to these studies. The review and assessment of potentially relevant codes and regulations indicate that ERDAM 0530, Nuclear Criticality Safety should be the controlling document for criticality safety for the SPI Project. In general, the criticality control approaches and philosophies for the SPI Project comply with this document

  16. 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)…

  17. "One Task Fits All"? The Roles of Task Complexity, Modality, and Working Memory Capacity in L2 Performance

    Science.gov (United States)

    Zalbidea, Janire

    2017-01-01

    The present study explores the independent and interactive effects of task complexity and task modality on linguistic dimensions of second language (L2) performance and investigates how these effects are modulated by individual differences in working memory capacity. Thirty-two intermediate learners of L2 Spanish completed less and more complex…

  18. Effects of cognitive appraisal and mental workload factors on performance in an arithmetic task.

    Science.gov (United States)

    Galy, Edith; Mélan, Claudine

    2015-12-01

    We showed in a previous study an additive interaction between intrinsic and extraneous cognitive loads and of participants' alertness in an 1-back working memory task. The interaction between intrinsic and extraneous cognitive loads was only observed when participants' alertness was low (i.e. in the morning). As alertness is known to reflect an individual's general functional state, we suggested that the working memory capacity available for germane cognitive load depends on a participant's functional state, in addition to intrinsic and extraneous loads induced by the task and task conditions. The relationships between the different load types and their assessment by specific load measures gave rise to a modified cognitive load model. The aim of the present study was to complete the model by determining to what extent and at what processing level an individual's characteristics intervene in order to implement efficient strategies in a working memory task. Therefore, the study explored participants' cognitive appraisal of the situation in addition to the load factors considered previously-task difficulty, time pressure and alertness. Each participant performed a mental arithmetic task in four different cognitive load conditions (crossover of two task difficulty conditions and of two time pressure conditions), both while their alertness was low (9 a.m.) and high (4 p.m.). Results confirmed an additive effect of task difficulty and time pressure, previously reported in the 1-back memory task, thereby lending further support to the modified cognitive load model. Further, in the high intrinsic and extraneous load condition, performance was reduced on the morning session (i.e. when alertness was low) on one hand, and in those participants' having a threat appraisal of the situation on the other hand. When these factors were included into the analysis, a performance drop occurred in the morning irrespective of cognitive appraisal, and with threat appraisal in the

  19. 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.

  20. 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.

  1. 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).

  2. Task Complexity, Student Perceptions of Vocabulary Learning in EFL, and Task Performance

    Science.gov (United States)

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

    2013-01-01

    Background: The study deepened our understanding of how students' self-ef?cacy beliefs contribute to the context of teaching English as a foreign language in the framework of cognitive mediational paradigm at a ?ne-tuned task-speci?c level. Aim: The aim was to examine the relationship among task complexity, self-ef?cacy beliefs, domain-related…

  3. 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.

  4. Sleep restriction and cognitive load affect performance on a simulated marksmanship task.

    Science.gov (United States)

    Smith, Carl D; Cooper, Adam D; Merullo, Donna J; Cohen, Bruce S; Heaton, Kristin J; Claro, Pedro J; Smith, Tracey

    2017-11-24

    Sleep restriction degrades cognitive and motor performance, which can adversely impact job performance and increase the risk of accidents. Military personnel are prone to operating under sleep restriction, and previous work suggests that military marksmanship may be negatively affected under such conditions. Results of these studies, however, are mixed and have often incorporated additional stressors (e.g. energy restriction) beyond sleep restriction. Moreover, few studies have investigated how the degree of difficulty of a marksmanship task impacts performance following sleep restriction. The purpose of the current experiment was to study the effects of sleep restriction on marksmanship while minimizing the potential influence of other forms of stress. A friend-foe discrimination challenge with greater or lesser degrees of complexity (high versus low load) was used as the primary marksmanship task. Active duty Soldiers were recruited, and allowed 2 h of sleep every 24 h over a 72-h testing period. Marksmanship tasks, cognitive assessment metrics and the NASA-Task Load Index were administered daily. Results indicated that reaction times to shoot foe targets and signal friendly targets slowed over time. In addition, the ability to correctly discriminate between friend and foe targets significantly decreased in the high-cognitive-load condition over time despite shot accuracy remaining stable. The NASA-Task Load Index revealed that, although marksmanship performance degraded, participants believed their performance did not change over time. These results further characterize the consequences of sleep restriction on marksmanship performance and the perception of performance, and reinforce the importance of adequate sleep among service members when feasible. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  5. Walking while performing working memory tasks changes the prefrontal cortex hemodynamic activations and gait kinematics

    Directory of Open Access Journals (Sweden)

    Ming-I Brandon Lin

    2016-05-01

    Full Text Available BackgroundIncreasing evidence suggests that walking while performing a concurrent task negatively influences gait performance. However, it remains unclear how higher-level cognitive processes and coordination of limb movements are altered in challenging walking environments. This study investigated the influence of cognitive task complexity and walking road condition on the neutral correlates of executive function and postural control in dual-task walking. MethodsTwenty-four healthy young adults completed a series of overground walks with three walking road conditions (wide, narrow, with obstacles with and without the concurrent n-back working memory tasks of two complexity levels (1-back and 3-back. Prefrontal brain activation was assessed by functional near-infrared spectroscopy. A three-dimensional motion analysis system was used simultaneously to measure gait performance and lower-extremity kinematics. Repeated measures analysis of variance were performed to examine the differences between the conditions. ResultsIn comparison with standing still, participants showed lower n-back task accuracy while walking, with the worst performance from the road with obstacles. Spatiotemporal gait parameters, lower-extremity joint movements, and the relative changes in oxygenated hemoglobin (HbO concentration levels were all significantly different across the task complexity and walking path conditions. While dual-tasking participants were found to flex their hips and knees less, leading to a slower gait speed, longer stride time, shorter step length, and greater gait variability than during normal walking. For narrow-road walking, smaller ankle dorsiflexion and larger hip flexion were observed, along with a reduced gait speed. Obstacle negotiation was mainly characterized by increased gait variability than other conditions. HbO levels appeared to be lower during dual-task walking than normal walking. Compared to wide and obstacle conditions, walking on

  6. Trajectories of Resilience during Dyadic Task Performance among Children Six to Seven Years of Age

    Science.gov (United States)

    Mykkänen, Arttu; Kronqvist, Eeva-Liisa; Järvelä, Sanna

    2013-01-01

    The aim of this study is to analyse resilience displayed by young children in dyadic task performance situations. Data were collected by videotaping children (aged six to seven years; N?=?40) during a geometrical task performance. Results describe ways in which children confronted the challenges during task performance, and the order in which the…

  7. Do tasks make a difference? Accounting for heterogeneity of performance of children with reading difficulties on tasks of executive function: findings from a meta-analysis.

    Science.gov (United States)

    Booth, Josephine N; Boyle, James M E; Kelly, Steve W

    2010-03-01

    Research studies have implicated executive functions in reading difficulties (RD). But while some studies have found children with RD to be impaired on tasks of executive function other studies report unimpaired performance. A meta-analysis was carried out to determine whether these discrepant findings can be accounted for by differences in the tasks of executive function that are utilized. A total of 48 studies comparing the performance on tasks of executive function of children with RD with their typically developing peers were included in the meta-analysis, yielding 180 effect sizes. An overall effect size of 0.57 (SE .03) was obtained, indicating that children with RD have impairments on tasks of executive function. However, effect sizes varied considerably suggesting that the impairment is not uniform. Moderator analysis revealed that task modality and IQ-achievement discrepancy definitions of RD influenced the magnitude of effect; however, the age and gender of participants and the nature of the RD did not have an influence. While the children's RD were associated with executive function impairments, variation in effect size is a product of the assessment task employed, underlying task demands, and definitional criteria.

  8. Performance Assessment National Review Group

    International Nuclear Information System (INIS)

    Lieberman, J.A.; Davis, S.N.; Harleman, D.R.F.

    1985-02-01

    Performance assessment involves predicting the potential radiological impact of a nuclear waste disposal system, taking into account all of the natural and engineered components of the system. It includes the analysis and evaluation of predicted system and component performance to determine compliance with regulatory performance criteria. In the context of the nuclear waste management program, performance assessment has five major purposes: to assist in the evaluation and selection of repository sites; to guide the research, development, and testing programs; to assist in the evaluation of repository designs; to assist in the evaluation of the design and performance of engineered barriers; and to show regulatory compliance and support repository licensing. Current performance assessment methodologies are still in the developmental stage. Only the simplest of bounding calculations have produced quantitative predictions of radionuclide releases. The methodologies require considerable extension and validation before they can provide answers suitable for project decisions and licensing. 135 refs., 9 figs., 1 tab

  9. Transcranial direct current stimulation over multiple days enhances motor performance of a grip task.

    Science.gov (United States)

    Fan, Julie; Voisin, Julien; Milot, Marie-Hélène; Higgins, Johanne; Boudrias, Marie-Hélène

    2017-09-01

    Recovery of handgrip is critical after stroke since it is positively related to upper limb function. To boost motor recovery, transcranial direct current stimulation (tDCS) is a promising, non-invasive brain stimulation technique for the rehabilitation of persons with stroke. When applied over the primary motor cortex (M1), tDCS has been shown to modulate neural processes involved in motor learning. However, no studies have looked at the impact of tDCS on the learning of a grip task in both stroke and healthy individuals. To assess the use of tDCS over multiple days to promote motor learning of a grip task using a learning paradigm involving a speed-accuracy tradeoff in healthy individuals. In a double-blinded experiment, 30 right-handed subjects (mean age: 22.1±3.3 years) participated in the study and were randomly assigned to an anodal (n=15) or sham (n=15) stimulation group. First, subjects performed the grip task with their dominant hand while following the pace of a metronome. Afterwards, subjects trained on the task, at their own pace, over 5 consecutive days while receiving sham or anodal tDCS over M1. After training, subjects performed de novo the metronome-assisted task. The change in performance between the pre and post metronome-assisted task was used to assess the impact of the grip task and tDCS on learning. Anodal tDCS over M1 had a significant effect on the speed-accuracy tradeoff function. The anodal tDCS group showed significantly greater improvement in performance (39.28±15.92%) than the sham tDCS group (24.06±16.35%) on the metronome-assisted task, t(28)=2.583, P=0.015 (effect size d=0.94). Anodal tDCS is effective in promoting grip motor learning in healthy individuals. Further studies are warranted to test its potential use for the rehabilitation of fine motor skills in stroke patients. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  10. 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....

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

    Science.gov (United States)

    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…

  12. Selected component failure rate values from fusion safety assessment tasks

    International Nuclear Information System (INIS)

    Cadwallader, L.C.

    1998-01-01

    This report is a compilation of component failure rate and repair rate values that can be used in magnetic fusion safety assessment tasks. Several safety systems are examined, such as gas cleanup systems and plasma shutdown systems. Vacuum system component reliability values, including large vacuum chambers, have been reviewed. Values for water cooling system components have also been reported here. The report concludes with the examination of some equipment important to personnel safety, atmospheres, combustible gases, and airborne releases of radioactivity. These data should be useful to system designers to calculate scoping values for the availability and repair intervals for their systems, and for probabilistic safety or risk analysts to assess fusion systems for safety of the public and the workers

  13. Selected component failure rate values from fusion safety assessment tasks

    Energy Technology Data Exchange (ETDEWEB)

    Cadwallader, L.C.

    1998-09-01

    This report is a compilation of component failure rate and repair rate values that can be used in magnetic fusion safety assessment tasks. Several safety systems are examined, such as gas cleanup systems and plasma shutdown systems. Vacuum system component reliability values, including large vacuum chambers, have been reviewed. Values for water cooling system components have also been reported here. The report concludes with the examination of some equipment important to personnel safety, atmospheres, combustible gases, and airborne releases of radioactivity. These data should be useful to system designers to calculate scoping values for the availability and repair intervals for their systems, and for probabilistic safety or risk analysts to assess fusion systems for safety of the public and the workers.

  14. Selected Component Failure Rate Values from Fusion Safety Assessment Tasks

    Energy Technology Data Exchange (ETDEWEB)

    Cadwallader, Lee Charles

    1998-09-01

    This report is a compilation of component failure rate and repair rate values that can be used in magnetic fusion safety assessment tasks. Several safety systems are examined, such as gas cleanup systems and plasma shutdown systems. Vacuum system component reliability values, including large vacuum chambers, have been reviewed. Values for water cooling system components have also been reported here. The report concludes with the examination of some equipment important to personnel safety, atmospheres, combustible gases, and airborne releases of radioactivity. These data should be useful to system designers to calculate scoping values for the availability and repair intervals for their systems, and for probabilistic safety or risk analysts to assess fusion systems for safety of the public and the workers.

  15. Relationship between Usefulness Assessments and Perceptions of Work Task Complexity and Search Topic Specificity: An Exploratory Study

    DEFF Research Database (Denmark)

    Ingwersen, Peter; Wang, Peiling

    2012-01-01

    This research investigates the relations between the usefulness assessments of retrieved documents and the perceptions of task complexity and search topic specificity. Twenty-three academic researchers submitted 65 real task-based information search topics. These task topics were searched...... in an integrated document collection consisting of full text research articles in PDFs, abstracts, and bibliographic records (the iSearch Test Collection in Physics). The search results were provided to the researchers who, as task performers, made assessments of usefulness using a four-point sale (highly, fairly......, marginally, or not useful). In addition, they also assessed the perceived task complexity (highly, fairly, and routine/low) and the perceived specificity of the search topic (highly, fairly, and generic/low). It is found that highly specific topics associate with all degrees of task complexity, whereas...

  16. Potential Performance Theory (PPT): A General Theory of Task Performance Applied to Morality

    Science.gov (United States)

    Trafimow, David; Rice, Stephen

    2008-01-01

    People can use a variety of different strategies to perform tasks and these strategies all have two characteristics in common. First, they can be evaluated in comparison with either an absolute or a relative standard. Second, they can be used at varying levels of consistency. In the present article, the authors develop a general theory of task…

  17. 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

    2015-07-01

    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.

  18. Effects of alcohol on attention orienting and dual-task performance during simulated driving: an event-related potential study.

    Science.gov (United States)

    Wester, Anne E; Verster, Joris C; Volkerts, Edmund R; Böcker, Koen B E; Kenemans, J Leon

    2010-09-01

    Driving is a complex task and is susceptible to inattention and distraction. Moreover, alcohol has a detrimental effect on driving performance, possibly due to alcohol-induced attention deficits. The aim of the present study was to assess the effects of alcohol on simulated driving performance and attention orienting and allocation, as assessed by event-related potentials (ERPs). Thirty-two participants completed two test runs in the Divided Attention Steering Simulator (DASS) with blood alcohol concentrations (BACs) of 0.00%, 0.02%, 0.05%, 0.08% and 0.10%. Sixteen participants performed the second DASS test run with a passive auditory oddball to assess alcohol effects on involuntary attention shifting. Sixteen other participants performed the second DASS test run with an active auditory oddball to assess alcohol effects on dual-task performance and active attention allocation. Dose-dependent impairments were found for reaction times, the number of misses and steering error, even more so in dual-task conditions, especially in the active oddball group. ERP amplitudes to novel irrelevant events were also attenuated in a dose-dependent manner. The P3b amplitude to deviant target stimuli decreased with blood alcohol concentration only in the dual-task condition. It is concluded that alcohol increases distractibility and interference from secondary task stimuli, as well as reduces attentional capacity and dual-task integrality.

  19. Working memory capacity predicts conflict-task performance

    NARCIS (Netherlands)

    Gulbinaite, Rasa; Johnson, Addie

    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

  20. Group cohesion, task performance, and the experimenter expectancy effect.

    NARCIS (Netherlands)

    Hoogstraten, J.; Vorst, H.C.M.

    1978-01-01

    Studied the effects of cohesion on task fulfillment and explored the influence of task fulfillment on the initial level of cohesion. Within 4-person groups of undergraduates, cohesion was manipulated successfully by a triple procedure. The level of cohesion was ascertained directly after the

  1. The impact of occipital lobe cortical thickness on cognitive task performance: An investigation in Huntington's Disease.

    Science.gov (United States)

    Johnson, Eileanoir B; Rees, Elin M; Labuschagne, Izelle; Durr, Alexandra; Leavitt, Blair R; Roos, Raymund A C; Reilmann, Ralf; Johnson, Hans; Hobbs, Nicola Z; Langbehn, Douglas R; Stout, Julie C; Tabrizi, Sarah J; Scahill, Rachael I

    2015-12-01

    The occipital lobe is an important visual processing region of the brain. Following consistent findings of early neural changes in the occipital lobe in Huntington's Disease (HD), we examined cortical thickness across four occipital regions in premanifest (preHD) and early HD groups compared with controls. Associations between cortical thickness in gene positive individuals and performance on six cognitive tasks, each with a visual component, were examined. In addition, the association between cortical thickness in gene positive participants and one non-visual motor task was also examined for comparison. Cortical thickness was determined using FreeSurfer on T1-weighted 3T MR datasets from controls (N=97), preHD (N=109) and HD (N=69) from the TRACK-HD study. Regression models were fitted to assess between-group differences in cortical thickness, and relationships between performance on the cognitive tasks, the motor task and occipital thickness were examined in a subset of gene-positive participants (N=141). Thickness of the occipital cortex in preHD and early HD participants was reduced compared with controls. Regionally-specific associations between reduced cortical thickness and poorer performance were found for five of the six cognitive tasks, with the strongest associations in lateral occipital and lingual regions. No associations were found with the cuneus. The non-visual motor task was not associated with thickness of any region. The heterogeneous pattern of associations found in the present study suggests that occipital thickness negatively impacts cognition, but only in regions that are linked to relatively advanced visual processing (e.g., lateral occipital, lingual regions), rather than in basic visual processing regions such as the cuneus. Our results show, for the first time, the functional implications of occipital atrophy highlighted in recent studies in HD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Automated Cognitive Health Assessment Using Smart Home Monitoring of Complex Tasks.

    Science.gov (United States)

    Dawadi, Prafulla N; Cook, Diane J; Schmitter-Edgecombe, Maureen

    2013-11-01

    One of the many services that intelligent systems can provide is the automated assessment of resident well-being. We hypothesize that the functional health of individuals, or ability of individuals to perform activities independently without assistance, can be estimated by tracking their activities using smart home technologies. In this paper, we introduce a machine learning-based method for assessing activity quality in smart homes. To validate our approach we quantify activity quality for 179 volunteer participants who performed a complex, interweaved set of activities in our smart home apartment. We observed a statistically significant correlation (r=0.79) between automated assessment of task quality and direct observation scores. Using machine learning techniques to predict the cognitive health of the participants based on task quality is accomplished with an AUC value of 0.64. We believe that this capability is an important step in understanding everyday functional health of individuals in their home environments.

  3. 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

  4. 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; 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

  5. Comparison of congruence judgment and auditory localization tasks for assessing the spatial limits of visual capture.

    Science.gov (United States)

    Bosen, Adam K; Fleming, Justin T; Brown, Sarah E; Allen, Paul D; O'Neill, William E; Paige, Gary D

    2016-12-01

    Vision typically has better spatial accuracy and precision than audition and as a result often captures auditory spatial perception when visual and auditory cues are presented together. One determinant of visual capture is the amount of spatial disparity between auditory and visual cues: when disparity is small, visual capture is likely to occur, and when disparity is large, visual capture is unlikely. Previous experiments have used two methods to probe how visual capture varies with spatial disparity. First, congruence judgment assesses perceived unity between cues by having subjects report whether or not auditory and visual targets came from the same location. Second, auditory localization assesses the graded influence of vision on auditory spatial perception by having subjects point to the remembered location of an auditory target presented with a visual target. Previous research has shown that when both tasks are performed concurrently they produce similar measures of visual capture, but this may not hold when tasks are performed independently. Here, subjects alternated between tasks independently across three sessions. A Bayesian inference model of visual capture was used to estimate perceptual parameters for each session, which were compared across tasks. Results demonstrated that the range of audiovisual disparities over which visual capture was likely to occur was narrower in auditory localization than in congruence judgment, which the model indicates was caused by subjects adjusting their prior expectation that targets originated from the same location in a task-dependent manner.

  6. Comparison of Congruence Judgment and Auditory Localization Tasks for Assessing the Spatial Limits of Visual Capture

    Science.gov (United States)

    Bosen, Adam K.; Fleming, Justin T.; Brown, Sarah E.; Allen, Paul D.; O'Neill, William E.; Paige, Gary D.

    2016-01-01

    Vision typically has better spatial accuracy and precision than audition, and as a result often captures auditory spatial perception when visual and auditory cues are presented together. One determinant of visual capture is the amount of spatial disparity between auditory and visual cues: when disparity is small visual capture is likely to occur, and when disparity is large visual capture is unlikely. Previous experiments have used two methods to probe how visual capture varies with spatial disparity. First, congruence judgment assesses perceived unity between cues by having subjects report whether or not auditory and visual targets came from the same location. Second, auditory localization assesses the graded influence of vision on auditory spatial perception by having subjects point to the remembered location of an auditory target presented with a visual target. Previous research has shown that when both tasks are performed concurrently they produce similar measures of visual capture, but this may not hold when tasks are performed independently. Here, subjects alternated between tasks independently across three sessions. A Bayesian inference model of visual capture was used to estimate perceptual parameters for each session, which were compared across tasks. Results demonstrated that the range of audio-visual disparities over which visual capture was likely to occur were narrower in auditory localization than in congruence judgment, which the model indicates was caused by subjects adjusting their prior expectation that targets originated from the same location in a task-dependent manner. PMID:27815630

  7. Quantitative assessment of airborne exposures generated during common cleaning tasks: a pilot study

    Directory of Open Access Journals (Sweden)

    Perry Melissa J

    2010-11-01

    Full Text Available Abstract Background A growing body of epidemiologic evidence suggests an association between exposure to cleaning products with asthma and other respiratory disorders. Thus far, these studies have conducted only limited quantitative exposure assessments. Exposures from cleaning products are difficult to measure because they are complex mixtures of chemicals with a range of physicochemical properties, thus requiring multiple measurement techniques. We conducted a pilot exposure assessment study to identify methods for assessing short term, task-based airborne exposures and to quantitatively evaluate airborne exposures associated with cleaning tasks simulated under controlled work environment conditions. Methods Sink, mirror, and toilet bowl cleaning tasks were simulated in a large ventilated bathroom and a small unventilated bathroom using a general purpose, a glass, and a bathroom cleaner. All tasks were performed for 10 minutes. Airborne total volatile organic compounds (TVOC generated during the tasks were measured using a direct reading instrument (DRI with a photo ionization detector. Volatile organic ingredients of the cleaning mixtures were assessed utilizing an integrated sampling and analytic method, EPA TO-17. Ammonia air concentrations were also measured with an electrochemical sensor embedded in the DRI. Results Average TVOC concentrations calculated for 10 minute tasks ranged 0.02 - 6.49 ppm and the highest peak concentrations observed ranged 0.14-11 ppm. TVOC time concentration profiles indicated that exposures above background level remained present for about 20 minutes after cessation of the tasks. Among several targeted VOC compounds from cleaning mixtures, only 2-BE was detectable with the EPA method. The ten minute average 2- BE concentrations ranged 0.30 -21 ppm between tasks. The DRI underestimated 2-BE exposures compared to the results from the integrated method. The highest concentration of ammonia of 2.8 ppm occurred

  8. Grip Strength and Its Relationship to Police Recruit Task Performance and Injury Risk: A Retrospective Cohort Study.

    Science.gov (United States)

    Orr, Robin; Pope, Rodney; Stierli, Michael; Hinton, Benjamin

    2017-08-21

    Suitable grip strength is a police occupational requirement. The aim of this study was to investigate the association between grip strength, task performance and injury risk in a police population. Retrospective data of police recruits (n = 169) who had undergone basic recruit training were provided, including handgrip strength results, occupational task performance measures (consisting of police task simulations [SIM], tactical options [TACOPS] and marksmanship assessments) and injury records. Left hand grip strength (41.91 ± 8.29 kg) measures showed a stronger correlation than right hand grip strength (42.15 ± 8.53 kg) with all outcome measures. Recruits whose grip strength scores were lower were significantly more susceptible to failing the TACOPS occupational task assessment than those with greater grip strength scores, with significant ( p ≤ 0.003) weak to moderate, positive correlations found between grip strength and TACOPS performance. A significant ( p performance, with those performing better in marksmanship having higher grip strength. Left hand grip strength was significantly associated with injury risk ( r = -0.181, p = 0.018) but right hand grip strength was not. A positive association exists between handgrip strength and police recruit task performance (notably TACOPS and marksmanship) with recruits who scored poorly on grip strength being at greatest risk of occupational assessment task failure.

  9. Improving Sensitivity to Detect Mild Cognitive Impairment: Cognitive Load Dual-Task Gait Speed Assessment.

    Science.gov (United States)

    MacAulay, Rebecca K; Wagner, Mark T; Szeles, Dana; Milano, Nicholas J

    2017-07-01

    Longitudinal research indicates that cognitive load dual-task gait assessment is predictive of cognitive decline and thus might provide a sensitive measure to screen for mild cognitive impairment (MCI). However, research among older adults being clinically evaluated for cognitive concerns, a defining feature of MCI, is lacking. The present study investigated the effect of performing a cognitive task on normal walking speed in patients presenting to a memory clinic with cognitive complaints. Sixty-one patients with a mean age of 68 years underwent comprehensive neuropsychological testing, clinical interview, and gait speed (simple- and dual-task conditions) assessments. Thirty-four of the 61 patients met criteria for MCI. Repeated measure analyses of covariance revealed that greater age and MCI both significantly associated with slower gait speed, pscognitive dual task within a clinically representative population. Cognitive load dual-task gait assessment may provide a cost efficient and sensitive measure to detect older adults at high risk of a dementia disorder. (JINS, 2017, 23, 493-501).

  10. Concept Software Based on Kinect for Assessing Dual-Task Ability of Elderly People.

    Science.gov (United States)

    Kayama, Hiroki; Okamoto, Kazuya; Nishiguchi, Shu; Nagai, Koutatsu; Yamada, Minoru; Aoyama, Tomoki

    2012-10-01

    Assessment of fall risk of elderly people is a critical issue. Dual-task (DT) ability is a criterion for risk assessment. We developed new concept software based on Microsoft (Redmond, WA) Kinect™ for assessing DT ability. The software is named "Dual-Task Tai Chi" (DTTC) and includes Tai Chi and number place (Sudoku) components. The purpose of this study is to validate the DTTC test for assessment of DT ability. Forty-five community-dwelling elderly (mean age, 74.1±6.6 years) individuals participated in this study. They performed DTTC, locomotive, cognitive, and DT tests. DT ability was evaluated with a 10-m walk under a cognitive-task condition and a 10-m walk under a manual-task condition. The correlation between the time taken to complete the DTTC test and each function test was determined using Pearson correlation coefficients. Stepwise multiple regression analysis was conducted to assess the relationship between the DTTC test results and results of the other tests. The time taken to complete the DTTC test was correlated with DT ability, locomotive functioning, and cognitive functioning. Results of stepwise multiple regression analysis confirmed that DT, balance, and cognitive ability are statistically significant. No statistically significant association was found for the other variables. The DTTC test quantitatively evaluates a compound function including DT, balance, and cognitive abilities.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Task performance in virtual environments used for cognitive rehabilitation after traumatic brain injury.

    Science.gov (United States)

    Christiansen, C; Abreu, B; Ottenbacher, K; Huffman, K; Masel, B; Culpepper, R

    1998-08-01

    This report describes a reliability study using a prototype computer-simulated virtual environment to assess basic daily living skills in a sample of persons with traumatic brain injury (TBI). The benefits of using virtual reality in training for situations where safety is a factor have been established in defense and industry, but have not been demonstrated in rehabilitation. Thirty subjects with TBI receiving comprehensive rehabilitation services at a residential facility. An immersive virtual kitchen was developed in which a meal preparation task involving multiple steps could be performed. The prototype was tested using subjects who completed the task twice within 7 days. The stability of performance was estimated using intraclass correlation coefficients (ICCs). The ICC value for total performance based on all steps involved in the meal preparation task was .73. When three items with low variance were removed the ICC improved to .81. Little evidence of vestibular optical side-effects was noted in the subjects tested. Adequate initial reliability exists to continue development of the environment as an assessment and training prototype for persons with brain injury.

  18. The Effect of Predicted Vehicle Displacement on Ground Crew Task Performance and Hardware Design

    Science.gov (United States)

    Atencio, Laura Ashley; Reynolds, David W.

    2011-01-01

    NASA continues to explore new launch vehicle concepts that will carry astronauts to low- Earth orbit to replace the soon-to-be retired Space Transportation System (STS) shuttle. A tall vertically stacked launch vehicle (> or =300 ft) is exposed to the natural environment while positioned on the launch pad. Varying directional winds and vortex shedding cause the vehicle to sway in an oscillating motion. Ground crews working high on the tower and inside the vehicle during launch preparations will be subjected to this motion while conducting critical closeout tasks such as mating fluid and electrical connectors and carrying heavy objects. NASA has not experienced performing these tasks in such environments since the Saturn V, which was serviced from a movable (but rigid) service structure; commercial launchers are likewise attended by a service structure that moves away from the vehicle for launch. There is concern that vehicle displacement may hinder ground crew operations, impact the ground system designs, and ultimately affect launch availability. The vehicle sway assessment objective is to replicate predicted frequencies and displacements of these tall vehicles, examine typical ground crew tasks, and provide insight into potential vehicle design considerations and ground crew performance guidelines. This paper outlines the methodology, configurations, and motion testing performed while conducting the vehicle displacement assessment that will be used as a Technical Memorandum for future vertically stacked vehicle designs.

  19. Performance assessment: a peer review

    International Nuclear Information System (INIS)

    Lieberman, J.A.; Lee, W.W.L.

    1986-01-01

    This paper describes the rationale, membership, operation and major observations of the Performance Assessment National Review Group. The Group was assembled by Weston at the request of the US Department of Energy Office of Civilian Radioactive Waste Management to review performance assessment work in the US basalt, salt and tuff repository projects. The purposes were to evaluate the adequacy of the current methods, identify deficiencies, and suggest potential improvement on repository performance assessment. To perform the review, Weston retained a group of distinguished consultants who have had extensive experience in disciplines pertinent to management of radioactive wastes including mathematical modeling of fluid transport. Topics reviewed included flow and transport, source term and uncertainty analysis. While the emphasis was on methodologies, the Projects were specifically requested to show currently available results so that the way they utilized familiar methodologies could be evaluated. This paper will highlight some of the technical observations of the Group as well as some managerial and institutional issues

  20. Internalizing versus Externalizing Control: Different Ways to Perform a Time-Based Prospective Memory Task

    Science.gov (United States)

    Huang, Tracy; Loft, Shayne; Humphreys, Michael S.

    2014-01-01

    "Time-based prospective memory" (PM) refers to performing intended actions at a future time. Participants with time-based PM tasks can be slower to perform ongoing tasks (costs) than participants without PM tasks because internal control is required to maintain the PM intention or to make prospective-timing estimates. However, external…

  1. Complexity, Accuracy, Fluency and Lexis in Task-Based Performance: A Synthesis of the Ealing Research

    Science.gov (United States)

    Skehan, Peter; Foster, Pauline

    2012-01-01

    This chapter will present a research synthesis of a series of studies, termed here the Ealing research. The studies use the same general framework to conceptualise tasks and task performance, enabling easier comparability. The different studies, although each is self-contained, build into a wider picture of task performance. The major point of…

  2. Determination of language lateralization using functional MRI during the performance of shiritori tasks in neurosurgery patients

    International Nuclear Information System (INIS)

    Takayama, Hideichi; Kobayashi, Masahito; Sugishita, Morihiro; Onozuka, Satoshi; Kawase, Takeshi

    2001-01-01

    Assessment of language lateralization is crucial in patients considered for neurological surgery. The authors used functional MRI (fMRI) in conjunction with shiritori, a kind of word-generation task as paradigms, to determine language lateralization in the patients. We used a 1.5 Tesla magnetic resonance imaging devise with an echo-planar imaging sequence. Thirty-two patients undergoing neurological surgery would alternately rest and silently perform shiritori during fMRI acquisition. Language lateralization was determined in 29 out of 32 patients. Twenty-two patients were considered as left-hemisphere dominant and seven were right-hemisphere dominant. Brain activation was seen in the prefrontal area, premotor area, superior temporal gyrus and parietal lobe of the dominant hemisphere, which is consistent with the results in normal adults. Language lateralization was particularly useful in a case of meningioma in the left lateral ventricle and in a case of AVM in the left temporoparietal region. fMRI with shiritori tasks revealed right-hemisphere dominance in both cases, which was also confirmed by intracarotid amobarbital (Wada) testing. Both lesions were treated successfully without causing any further deficit to the patients' language function. These results suggest that fMRI with shiritori tasks can be used to assess language lateralization non-invasively, compared with the current techniques, such as intracarotid amobarbital testing and cortical electrostimulation mapping. Thus, fMRI with shiritori tasks has significant clinical potential as a presurgical evaluation tool. (author)

  3. Determination of language lateralization using functional MRI during the performance of shiritori tasks in neurosurgery patients

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, Hideichi; Kobayashi, Masahito [Mihara Memorial Hospital, Isesaki, Gunma (Japan); Sugishita, Morihiro; Onozuka, Satoshi; Kawase, Takeshi

    2001-03-01

    Assessment of language lateralization is crucial in patients considered for neurological surgery. The authors used functional MRI (fMRI) in conjunction with shiritori, a kind of word-generation task as paradigms, to determine language lateralization in the patients. We used a 1.5 Tesla magnetic resonance imaging devise with an echo-planar imaging sequence. Thirty-two patients undergoing neurological surgery would alternately rest and silently perform shiritori during fMRI acquisition. Language lateralization was determined in 29 out of 32 patients. Twenty-two patients were considered as left-hemisphere dominant and seven were right-hemisphere dominant. Brain activation was seen in the prefrontal area, premotor area, superior temporal gyrus and parietal lobe of the dominant hemisphere, which is consistent with the results in normal adults. Language lateralization was particularly useful in a case of meningioma in the left lateral ventricle and in a case of AVM in the left temporoparietal region. fMRI with shiritori tasks revealed right-hemisphere dominance in both cases, which was also confirmed by intracarotid amobarbital (Wada) testing. Both lesions were treated successfully without causing any further deficit to the patients' language function. These results suggest that fMRI with shiritori tasks can be used to assess language lateralization non-invasively, compared with the current techniques, such as intracarotid amobarbital testing and cortical electrostimulation mapping. Thus, fMRI with shiritori tasks has significant clinical potential as a presurgical evaluation tool. (author)

  4. Task-based dermal exposure models for regulatory risk assessment.

    Science.gov (United States)

    Warren, Nicholas D; Marquart, Hans; Christopher, Yvette; Laitinen, Juha; VAN Hemmen, Joop J

    2006-07-01

    The regulatory risk assessment of chemicals requires the estimation of occupational dermal exposure. Until recently, the models used were either based on limited data or were specific to a particular class of chemical or application. The EU project RISKOFDERM has gathered a considerable number of new measurements of dermal exposure together with detailed contextual information. This article describes the development of a set of generic task-based models capable of predicting potential dermal exposure to both solids and liquids in a wide range of situations. To facilitate modelling of the wide variety of dermal exposure situations six separate models were made for groupings of exposure scenarios called Dermal Exposure Operation units (DEO units). These task-based groupings cluster exposure scenarios with regard to the expected routes of dermal exposure and the expected influence of exposure determinants. Within these groupings linear mixed effect models were used to estimate the influence of various exposure determinants and to estimate components of variance. The models predict median potential dermal exposure rates for the hands and the rest of the body from the values of relevant exposure determinants. These rates are expressed as mg or microl product per minute. Using these median potential dermal exposure rates and an accompanying geometric standard deviation allows a range of exposure percentiles to be calculated.

  5. Effects of Dual-Task Management and Resistance Training on Gait Performance in Older Individuals: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Bettina Wollesen

    2017-12-01

    Full Text Available Background: Dual-task (DT training is a well-accepted modality for fall prevention in older adults. DT training should include task-managing strategies such as task switching or task prioritization to improve gait performance under DT conditions.Methods: We conducted a randomized controlled trial to evaluate a balance and task managing training (BDT group in gait performance compared to a single task (ST strength and resistance training and a control group, which received no training. A total of 78 older individuals (72.0 ± 4.9 years participated in this study. The DT group performed task managing training incorporating balance and coordination tasks while the ST group performed resistance training only. Training consisted of 12 weekly sessions, 60 min each, for 12 weeks. We assessed the effects of ST and BDT training on walking performance under ST and DT conditions in independent living elderly adults. ST and DT walking (visual verbal Stroop task were measured utilizing a treadmill at self-selected walking speed (mean for all groups: 4.4 ± 1 km h-1. Specific gait variables, cognitive performance, and fear of falling were compared between all groups.>Results: Training improved gait performance for step length (p < 0.001 and gait-line (ST: p < 0.01; DT p < 0.05 in both training groups. The BDT training group showed greater improvements in step length (p < 0.001 and gait-line (p < 0.01 during DT walking but did not have changes in cognitive performance. Both interventions reduced fear of falling (p < 0.05.Conclusion: Implementation of task management strategies into balance and strength training in our population revealed a promising modality to prevent falls in older individuals.Trial registration: German register of clinical trials DRKS00012382.

  6. Sex differences in muscular load among house painters performing identical work tasks

    DEFF Research Database (Denmark)

    Meyland, Jacob; Heilskov-Hansen, Thomas; Alkjær, Tine

    2014-01-01

    PURPOSE: The present study aimed to estimate possible differences in upper body muscular load between male and female house painters performing identical work tasks. Sex-related differences in muscular load may help explain why women, in general, have more musculoskeletal complaints than men....... METHODS: In a laboratory setting, 16 male and 16 female house painters performed nine standardised work tasks common to house painters. Unilateral electromyography (EMG) recordings were obtained from the supraspinatus muscle by intramuscular electrodes and from the trapezius, extensor and flexor carpi...... radialis muscles by surface electrodes. Relative muscular loads in %EMGmax as well as exerted force in Newton, based on ramp calibrations, were assessed. Sex differences were tested using a mixed model approach. RESULTS: Women worked at about 50% higher relative muscular loads than men in the supraspinatus...

  7. Routing Cooperating Vehicles to Perform Precedence-Linked Tasks

    National Research Council Canada - National Science Library

    Vakhutinsky, Andrew; Wu, Cynara

    2005-01-01

    The problem of scheduling cooperating vehicles is a generalization of the classical vehicle routing problem where certain tasks are linked by precedence constraints and vehicles have varying constrained resources...

  8. Grammatical production deficits in PPA: Relating narrative and structured task performance

    Directory of Open Access Journals (Sweden)

    Elena Barbieri

    2015-05-01

    Full Text Available Introduction Grammatical production impairments in primary progressive aphasia (PPA have been investigated using structured language tasks and analysis of narrative language samples (for review see Thompson & Mack, 2014; Wilson et al., 2012. However, little research has examined the relationship between them in PPA. Whereas structured tasks often assess production accuracy at different levels of syntactic complexity (e.g., Thompson et al., 2013, narrative measures typically assess overall lexical and grammatical usage (e.g., % grammatical sentences; noun-to-verb ratio, with lesser emphasis on complexity. The present study investigated the relationship between narrative measures of grammatical production and performance on structured language tests in the domains of syntax, verb morphology, and verb-argument structure (VAS. Materials and methods Data from 101 individuals with PPA were included. Participants completed a test battery including the Northwestern Assessment of Verbs and Sentences (NAVS, Thompson, 2011, the Northwestern Assessment of Verb Inflection (NAVI, Lee & Thompson, experimental version and the Northwestern Anagram Test (NAT, Thompson, Weintraub, & Mesulam, 2012. Grammatical production deficits were quantified as follows: for syntax, accuracy of non-canonical sentence production on the NAVS Sentence Production Priming Test (SPPT and the NAT; for morphology, the accuracy on finite verbs on the NAVI; for VAS, the accuracy of sentences produced with 2- and 3-argument verbs on the NAVS Argument Structure Production Test (ASPT. Cinderella narrative samples were analyzed using the Northwestern Narrative Language Analysis system (e.g., Thompson et al., 2012. For syntax, complexity was measured by the ratio of syntactically complex to simple sentences produced, whereas accuracy was indexed by computing the proportion of words with a locally grammatical lexical category. Morphological complexity was measured by mean number of verb

  9. Analysis of Skeletal Muscle Metrics as Predictors of Functional Task Performance

    Science.gov (United States)

    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.

  10. DOE site performance assessment activities

    International Nuclear Information System (INIS)

    1990-07-01

    Information on performance assessment capabilities and activities was collected from eight DOE sites. All eight sites either currently dispose of low-level radioactive waste (LLW) or plan to dispose of LLW in the near future. A survey questionnaire was developed and sent to key individuals involved in DOE Order 5820.2A performance assessment activities at each site. The sites surveyed included: Hanford Site (Hanford), Idaho National Engineering Laboratory (INEL), Los Alamos National Laboratory (LANL), Nevada Test Site (NTS), Oak Ridge National Laboratory (ORNL), Paducah Gaseous Diffusion Plant (Paducah), Portsmouth Gaseous Diffusion Plant (Portsmouth), and Savannah River Site (SRS). The questionnaire addressed all aspects of the performance assessment process; from waste source term to dose conversion factors. This report presents the information developed from the site questionnaire and provides a comparison of site-specific performance assessment approaches, data needs, and ongoing and planned activities. All sites are engaged in completing the radioactive waste disposal facility performance assessment required by DOE Order 5820.2A. Each site has achieved various degrees of progress and have identified a set of critical needs. Within several areas, however, the sites identified common needs and questions

  11. Balance Performance Is Task Specific in Older Adults

    Directory of Open Access Journals (Sweden)

    Ayelet Dunsky

    2017-01-01

    Full Text Available Balance ability among the elderly is a key component in the activities of daily living and is divided into two types: static and dynamic. For clinicians who wish to assess the risk of falling among their elderly patients, it is unclear if more than one type of balance test can be used to measure their balance impairment. In this study, we examined the association between static balance measures and two dynamic balance field tests. One hundred and twelve community-dwelling older adults (mean age 74.6 participated in the study. They underwent the Tetrax static postural assessment and then performed the Timed Up and Go (TUG and the Functional Reach (FR Test as dynamic balance tests. In general, low-moderate correlations were found between the two types of balance tests. For women, age and static balance parameters explained 28.1–40.4% of the variance of TUG scores and 14.6–24% of the variance of FR scores. For men, age and static balance parameters explained 9.5–31.2% of the variance of TUG scores and 23.9–41.7% of the variance of FR scores. Based on our findings, it is suggested that a combination of both static and dynamic tests be used for assessing postural balance ability.

  12. 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.

  13. 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.

  14. Effect of Tai Chi Training on Dual-Tasking Performance That Involves Stepping Down among Stroke Survivors: A Pilot Study.

    Science.gov (United States)

    Chan, Wing-Nga; Tsang, William Wai-Nam

    2017-01-01

    Descending stairs demands attention and neuromuscular control, especially with dual-tasking. Studies have demonstrated that stroke often degrades a survivor's ability to descend stairs. Tai Chi has been shown to improve dual-tasking performance of healthy older adults, but no such study has been conducted in stroke survivors. This study investigated the effect of Tai Chi training on dual-tasking performance that involved stepping down and compared it with that of conventional exercise among stroke survivors. Subjects were randomized into Tai Chi ( n = 9), conventional exercise ( n = 8), and control ( n = 9) groups. Those in the former two groups received 12-week training. Assessments included auditory Stroop test, stepping down test, and dual-tasking test involving both simultaneously. They were evaluated before training (time-1), after training (time-2), and one month after training (time-3). Tai Chi group showed significant improvement in the auditory Stroop test from time-1 to time-3 and the performance was significantly better than that of the conventional exercise group in time-3. No significant effect was found in the stepping down task or dual-tasking in the control group. These results suggest a beneficial effect of Tai Chi training on cognition among stroke survivors without compromising physical task performance in dual-tasking. The effect was better than the conventional exercise group. Nevertheless, further research with a larger sample is warranted.

  15. Effect of Tai Chi Training on Dual-Tasking Performance That Involves Stepping Down among Stroke Survivors: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Wing-Nga Chan

    2017-01-01

    Full Text Available Descending stairs demands attention and neuromuscular control, especially with dual-tasking. Studies have demonstrated that stroke often degrades a survivor’s ability to descend stairs. Tai Chi has been shown to improve dual-tasking performance of healthy older adults, but no such study has been conducted in stroke survivors. This study investigated the effect of Tai Chi training on dual-tasking performance that involved stepping down and compared it with that of conventional exercise among stroke survivors. Subjects were randomized into Tai Chi (n=9, conventional exercise (n=8, and control (n=9 groups. Those in the former two groups received 12-week training. Assessments included auditory Stroop test, stepping down test, and dual-tasking test involving both simultaneously. They were evaluated before training (time-1, after training (time-2, and one month after training (time-3. Tai Chi group showed significant improvement in the auditory Stroop test from time-1 to time-3 and the performance was significantly better than that of the conventional exercise group in time-3. No significant effect was found in the stepping down task or dual-tasking in the control group. These results suggest a beneficial effect of Tai Chi training on cognition among stroke survivors without compromising physical task performance in dual-tasking. The effect was better than the conventional exercise group. Nevertheless, further research with a larger sample is warranted.

  16. 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.

  17. Performance monitoring and response conflict resolution associated with choice stepping reaction tasks.

    Science.gov (United States)

    Watanabe, Tatsunori; Tsutou, Kotaro; Saito, Kotaro; Ishida, Kazuto; Tanabe, Shigeo; Nojima, Ippei

    2016-11-01

    Choice reaction requires response conflict resolution, and the resolution processes that occur during a choice stepping reaction task undertaken in a standing position, which requires maintenance of balance, may be different to those processes occurring during a choice reaction task performed in a seated position. The study purpose was to investigate the resolution processes during a choice stepping reaction task at the cortical level using electroencephalography and compare the results with a control task involving ankle dorsiflexion responses. Twelve young adults either stepped forward or dorsiflexed the ankle in response to a visual imperative stimulus presented on a computer screen. We used the Simon task and examined the error-related negativity (ERN) that follows an incorrect response and the correct-response negativity (CRN) that follows a correct response. Error was defined as an incorrect initial weight transfer for the stepping task and as an incorrect initial tibialis anterior activation for the control task. Results revealed that ERN and CRN amplitudes were similar in size for the stepping task, whereas the amplitude of ERN was larger than that of CRN for the control task. The ERN amplitude was also larger in the stepping task than the control task. These observations suggest that a choice stepping reaction task involves a strategy emphasizing post-response conflict and general performance monitoring of actual and required responses and also requires greater cognitive load than a choice dorsiflexion reaction. The response conflict resolution processes appear to be different for stepping tasks and reaction tasks performed in a seated position.

  18. Performance assessment - risk assessment vive la differences

    International Nuclear Information System (INIS)

    Nitschke, R.L.

    1997-01-01

    In the sister worlds of radioactive waste management disposal and environmental restoration, there are two similar processes and computational approaches for determining the acceptability of the proposed activities. While similar, these two techniques can lead to confusion and misunderstanding if the differences are not recognized and appreciated. In the case of radioactive waste management, the performance assessment process is used to determine compliance with certain prescribed 'performance objectives'. These objectives are designed to ensure that the disposal of radioactive (high-level, low-level, and/or transuranic) waste will be protective of human health and the environment. The environmental link is primarily through assuring protection of the groundwater as a resource. In the case of environmental restoration, the risk assessment process is used to determine the proper remedial action response, if any, for a past hazardous waste release. The process compares the 'no action' or 'leave as is' option with both carcinogenic and noncarcinogenic values for human health to determine the need for any action and to help to help determine just what the appropriate action would need to be. The impacts to the ecological system are evaluated in a slightly, different but similar fashion. Now the common objectives between these two processes notwithstanding. There are some key and fundamental differences that need to be answered that make direct comparisons or a common approach inappropriate. Failure to recognize this can lead to confusion and misunderstanding. This can be particularly problematic when one is faced with an active disposal facility located within the boundaries of an environmental restoration site as is the case at the Idaho National Engineering Laboratory (INEL). Through a critical evaluation of the performance assessment and risk assessment processes, highlighting both similarities and differences, it is hoped that greater understanding and appreciation

  19. Performance on the Hamilton search task, and the influence of lateralization, in captive orange-winged Amazon parrots (Amazona amazonica).

    Science.gov (United States)

    Cussen, Victoria A; Mench, Joy A

    2014-07-01

    Psittacines are generally considered to possess cognitive abilities comparable to those of primates. Most psittacine research has evaluated performance on standardized complex cognition tasks, but studies of basic cognitive processes are limited. We tested orange-winged Amazon parrots (Amazona amazonica) on a spatial foraging assessment, the Hamilton search task. This task is a standardized test used in human and non-human primate studies. It has multiple phases, which require trial and error learning, learning set breaking, and spatial memory. We investigated search strategies used to complete the task, cognitive flexibility, and long-term memory for the task. We also assessed the effects of individual strength of motor lateralization (foot preference) and sex on task performance. Almost all (92%) of the parrots acquired the task. All had significant foot preferences, with 69% preferring their left foot, and showed side preferences contralateral to their preferred limb during location selection. The parrots were able to alter their search strategies when reward contingencies changed, demonstrating cognitive flexibility. They were also able to remember the task over a 6-month period. Lateralization had a significant influence on learning set acquisition but no effect on cognitive flexibility. There were no sex differences. To our knowledge, this is the first cognitive study using this particular species and one of the few studies of cognitive abilities in any Neotropical parrot species.

  20. Aerobic Fitness and Cognitive Development: Event-Related Brain Potential and Task Performance Indices of Executive Control in Preadolescent Children

    Science.gov (United States)

    Hillman, Charles H.; Buck, Sarah M.; Themanson, Jason R.; Pontifex, Matthew B.; Castelli, Darla M.

    2009-01-01

    The relationship between aerobic fitness and executive control was assessed in 38 higher- and lower-fit children (M[subscript age] = 9.4 years), grouped according to their performance on a field test of aerobic capacity. Participants performed a flanker task requiring variable amounts of executive control while event-related brain potential…

  1. 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.

  2. Social motivation in prospective memory: higher importance ratings and reported performance rates for social tasks.

    Science.gov (United States)

    Penningroth, Suzanna L; Scott, Walter D; Freuen, Margaret

    2011-03-01

    Few studies have addressed social motivation in prospective memory (PM). In a pilot study and two main studies, we examined whether social PM tasks possess a motivational advantage over nonsocial PM tasks. In the pilot study and Study 1, participants listed their real-life important and less important PM tasks. Independent raters categorized the PM tasks as social or nonsocial. Results from both studies showed a higher proportion of tasks rated as social when important tasks were requested than when less important tasks were requested. In Study 1, participants also reported whether they had remembered to perform each PM task. Reported performance rates were higher for tasks rated as social than for those rated as nonsocial. Finally, in Study 2, participants rated the importance of two hypothetical PM tasks, one social and one nonsocial. The social PM task was rated higher in importance. Overall, these findings suggest that social PM tasks are viewed as more important than nonsocial PM tasks and they are more likely to be performed. We propose that consideration of the social relevance of PM will lead to a more complete and ecologically valid theoretical description of PM performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  3. Development of a valid simulation assessment for a military dismounted assault task.

    Science.gov (United States)

    Silk, Aaron J; Billing, Daniel C

    2013-03-01

    The Australian Defence Force is currently developing physical standards commensurate with job demands. Vital to this development process has been the accurate profiling of common military tasks. One such task required of all dismounted combat soldiers, an offensive assault on an enemy force, was the subject of in-depth profiling. In addition to overall assault performance, potential differences among patrol roles (scout, gunner, and flank) were investigated. Three different mock assaults of 100 to 150 m were performed by three patrols comprising qualified experienced infantry soldiers. Each soldier was fitted with a heart rate monitor and wore a global positioning device. Average assault duration was 6.5 minutes and required nineteen 7-m bounds performed on a 22-seconds duty cycle at 75% heart rate reserve and a work to rest ratio 1:4. Assaults conducted in more densely vegetated terrain resulted in significantly reduced (p 0.05). As a result of profiling the assault task, a valid simulation capable of assessing soldiers' physical capacity to perform this task was developed. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

  4. Task-based assessment of breast tomosynthesis: Effect of acquisition parameters and quantum noise1

    OpenAIRE

    Reiser, I.; Nishikawa, R. M.

    2010-01-01

    Purpose: Tomosynthesis is a promising modality for breast imaging. The appearance of the tomosynthesis reconstructed image is greatly affected by the choice of acquisition and reconstruction parameters. The purpose of this study was to investigate the limitations of tomosynthesis breast imaging due to scan parameters and quantum noise. Tomosynthesis image quality was assessed based on performance of a mathematical observer model in a signal-known exactly (SKE) detection task.

  5. Conservatism and liberalism predict performance in two nonideological cognitive tasks.

    Science.gov (United States)

    Bernabel, Rodolpho Talaisys; Oliveira, Amâncio

    2017-01-01

    Intuitive thinking would argue that political or ideological orientation does not correlate with nonpolitical decisions, and certainly not with nonideological cognitive tasks. However, that is what happens in some cases. Previous neuropolitics studies have found that liberals are more adept at dealing with novel information than conservatives. This finding suggests that conservatives and liberals possess different cognitive skills. For the purposes of this article, two studies were executed to test whether this difference remained in alternative environmental settings. To this end, two novel cognitive tasks were designed in which one type of ideology or another was privileged according to the cognitive environment created by the tasks. Experimental findings indicate that liberals committed fewer errors than conservatives in one kind of cognitive environment, while conservatives scored higher in another.

  6. Dizocilpine (MK-801) impairs learning in the active place avoidance task but has no effect on the performance during task/context alternation.

    Science.gov (United States)

    Vojtechova, Iveta; Petrasek, Tomas; Hatalova, Hana; Pistikova, Adela; Vales, Karel; Stuchlik, Ales

    2016-05-15

    The prevention of engram interference, pattern separation, flexibility, cognitive coordination and spatial navigation are usually studied separately at the behavioral level. Impairment in executive functions is often observed in patients suffering from schizophrenia. We have designed a protocol for assessing these functions all together as behavioral separation. This protocol is based on alternated or sequential training in two tasks testing different hippocampal functions (the Morris water maze and active place avoidance), and alternated or sequential training in two similar environments of the active place avoidance task. In Experiment 1, we tested, in adult rats, whether the performance in two different spatial tasks was affected by their order in sequential learning, or by their day-to-day alternation. In Experiment 2, rats learned to solve the active place avoidance task in two environments either alternately or sequentially. We found that rats are able to acquire both tasks and to discriminate both similar contexts without obvious problems regardless of the order or the alternation. We used two groups of rats, controls and a rat model of psychosis induced by a subchronic intraperitoneal application of 0.08mg/kg of dizocilpine (MK-801), a non-competitive antagonist of NMDA receptors. Dizocilpine had no selective effect on parallel/sequential learning of tasks/contexts. However, it caused hyperlocomotion and a significant deficit in learning in the active place avoidance task regardless of the task alternation. Cognitive coordination tested by this task is probably more sensitive to dizocilpine than spatial orientation because no hyperactivity or learning impairment was observed in the Morris water maze. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Performance of patients with frontotemporal lobar degeneration on artistic tasks: A pilot study.

    Science.gov (United States)

    Anauate, Maria Cristina; Bahia, Valéria Santoro; Nitrini, Ricardo; Radanovic, Marcia

    2014-01-01

    Several studies have addressed visuospatial and executive skills in artistic activities in Frontotemporal Lobar Degeneration (FTLD) and Alzheimer's disease (AD). To investigate the performance of FTLD patients compared to controls on two artistic tasks. Four FTLD patients with mean age of 57 (8.7) years and schooling of 12.2 (4.5) years plus 10 controls with mean age of 62.9 (8.6) years and schooling of 12.3 (4.6) years, were assessed using the Lowenstein Occupational Therapy Cognitive Assessment (LOTCA) and by a three-stage artistic protocol including visual observation, copying and collage, based on a Sisley painting. FTLD patients had lower scores than controls on Visuospatial Perception, Copy, Collage, Examiner's Observation, and Total, showing distinct patterns of performance according to FTLD sub-type: semantic PPA, nonfluent PPA and bvFTD. FTLD patients presented impairment in the visuospatial and executive skills required to perform artistic tasks. We demonstrated that the application of the instrument as a complimentary method for assessing cognitive skills in this group of patients is possible. Further studies addressing larger and more homogeneous samples of FTLD patients as well as other dementias are warranted.

  8. Evaluation of Functional Correlation of Task-Specific Muscle Synergies with Motor Performance in Patients Poststroke

    Directory of Open Access Journals (Sweden)

    Si Li

    2017-07-01

    Full Text Available The central nervous system produces movements by activating specifically programmed muscle synergies that are also altered with injuries in the brain, such as stroke. In this study, we hypothesize that there exists a positive correlation between task-specific muscle synergy and motor functions at joint and task levels in patients following stroke. The purpose here is to define and evaluate neurophysiological metrics based on task-specific muscle synergy for assessing motor functions in patients. A patient group of 10 subjects suffering from stroke and a control group of nine age-matched healthy subjects were recruited to participate in this study. Electromyography (EMG signals and movement kinematics were recorded in patients and control subjects while performing arm reaching tasks. Muscle synergies of individual patients were extracted off-line from EMG records of each patient, and a baseline pattern of muscle synergy was obtained from the pooled EMG data of all nine control subjects. Peak velocities and movement durations of each reaching movement were computed from measured kinematics. Similarity indices of matching components to those of the baseline synergy were defined by synergy vectors and time profiles, respectively, as well as by a combined similarity of vector and time profile. Results showed that pathological synergies of patients were altered from the characteristics of baseline synergy with missing components, or varied vector patterns and time profiles. The kinematic performance measured by peak velocities and movement durations was significantly poorer for the patient group than the control group. In patients, all three similarity indices were found to correlate significantly to the kinematics of movements for the reaching tasks. The correlation to the Fugl-Meyer score of arm was the highest with the vector index, the lowest with the time profile index, and in between with the combined index. These findings illustrate that the

  9. 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.

  10. Improving balance, mobility, and dual-task performance in an adolescent with cerebral palsy: A case report.

    Science.gov (United States)

    Fisher-Pipher, Sarah; Kenyon, Lisa K; Westman, Marci

    2017-07-01

    Improving functional mobility is often a desired outcome for adolescents with cerebral palsy (CP). Traditional neurorehabilitation approaches are frequently directed at impairments; however, improvements may not be carried over into functional mobility. The purpose of this case report was to describe the examination, intervention, and outcomes of a task-oriented physical therapy intervention program to improve dynamic balance, functional mobility, and dual-task performance in an adolescent with CP. The participant was a 15-year-old girl with spastic triplegic CP (Gross Motor Classification System Level II). Examination procedures included the Canadian Occupational Performance Measure, 6-minute walk test, Muscle Power Sprint Test, 10 x 5-meter sprint test, Timed Up and Down Stairs Test, Gross Motor Function Measure, Gillette Functional Assessment Questionnaire, and functional lower extremity strength tests. Intervention focused on task-oriented dynamic balance and mobility tasks that incorporated coordination and speed demands as well as task-specific lower extremity and trunk strengthening activities. Dual task demands were integrated into all intervention activities. Post-intervention testing revealed improvements in cardiovascular endurance, anaerobic power, agility, stair climbing, gross motor skills, and mobility. The participant appeared to benefit from a task-oriented program to improve dynamic balance, functional mobility, and dual-task performance.

  11. Motivation, Intentionality, and Mind Wandering: Implications for Assessments of Task-Unrelated Thought

    Science.gov (United States)

    Seli, Paul; Cheyne, James Allan; Xu, Mengran; Purdon, Christine; Smilek, Daniel

    2015-01-01

    Researchers of mind wandering frequently assume that (a) participants are motivated to do well on the tasks they are given, and (b) task-unrelated thoughts (TUTs) that occur during task performance reflect unintentional, unwanted thoughts that occur despite participants' best intentions to maintain task-focus. Given the relatively boring and…

  12. 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.

  13. Relationship between weekend catch-up sleep and poor performance on attention tasks in Korean adolescents.

    Science.gov (United States)

    Kim, Seog Ju; Lee, Yu Jin; Cho, Seong-Jin; Cho, In-Hee; Lim, Weonjeong; Lim, Wonshin

    2011-09-01

    To investigate the relationship between insufficient sleep and poor attention in Korean adolescents, adjusting for potential confounding factors of depressed mood and habitual snoring. School-based cross-sectional study. Eight high schools in 3 cities in the Republic of Korea. A sample of 2638 urban high school students (42.2% male and 57.8% female; mean [SD] age, 17.3 [0.6] years [age range, 14-19 years]) completed questionnaires and computerized attention tasks during the school term. Weekend catch-up sleep. Self-reported sleep schedules and habits, including sleep duration, bedtime, wake-up time, depressed mood, and habitual snoring. Also measured were numbers of omission and commission errors on computerized attention tasks. The mean (SD) sleep duration on weekdays was 5 hours 42 minutes (1 hour 0 minutes) per day and on weekends was 8 hours 24 minutes (1 hour 36 minutes) per day. The mean (SD) weekend catch-up sleep was 2 hours 42 minutes (1 hour 42 minutes) per day. After adjusting for age, sex, depressed mood (Beck Depression Inventory score, ≥10), habitual snoring, and weekday sleep duration, increased weekend catch-up sleep was significantly associated with more omission and commission errors on sustained attention tasks (P sleep as an indicator of insufficient weekday sleep is associated with poor performance on objective attention tasks. Assessment of catch-up sleep and sleep duration may be useful for physicians to evaluate sleep insufficiency and its adverse effects on attention in adolescents.

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

    Science.gov (United States)

    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

  15. Unscrambling jumbled sentences: An authentic task for English language assessment?

    Directory of Open Access Journals (Sweden)

    Betty Lanteigne

    2017-06-01

    Full Text Available Jumbled sentence items in language assessment have been criticized by some authors as inauthentic. However, unscrambling jumbled sentences is a common occurrence in real-world communication in English as a lingua franca. Naturalistic inquiry identified 54 instances of jumbled sentence use in daily life in Dubai/Sharjah, where English is widely used as a lingua franca. Thus it is seen that jumbled sentence test items can reflect real-world language use. To evaluate scrambled sentence test items, eight test item types developed from one jumbled sentence instance (“Want taxi Dubai you?” were analyzed in terms of interactivity and authenticity. Items ranged from being completely decontextualized, non-interactive, and inauthentic to being fully contextualized, interactive, and authentic. To determine appropriate assessment standards for English tests in schools in this region, the English language standards for schools and English language requirements for university admission in the UAE were analyzed. Schools in Dubai/Sharjah use Inner Circle English varieties of English (e.g., British or American English as the standard for evaluation, as well as non-native-English-speaker varieties (e.g., Indian English(es. Also, students applying to English-medium universities in the UAE must meet the required scores on standardized English tests including the IELTS and TOEFL. Standards for evaluation of communication in English involving tasks of jumbled sentences in classroom tests must reflect the language learning goals of the school and community. Thus standards for classroom assessment of English in Dubai/Sharjah are determined by local schools’ and universities’ policies.

  16. Cognitive function predicts listening effort performance during complex tasks in normally aging adults

    Directory of Open Access Journals (Sweden)

    Jennine Harvey

    2017-01-01

    Full Text Available Purpose: This study examines whether cognitive function, as measured by the subtests of the Woodcock–Johnson III (WCJ-III assessment, predicts listening-effort performance during dual tasks across the adults of varying ages. Materials and Methods: Participants were divided into two groups. Group 1 consisted of 14 listeners (number of females = 11 who were 41–61 years old [mean = 53.18; standard deviation (SD = 5.97]. Group 2 consisted of 15 listeners (number of females = 9 who were 63–81 years old (mean = 72.07; SD = 5.11. Participants were administered the WCJ-III Memory for Words, Auditory Working Memory, Visual Matching, and Decision Speed subtests. All participants were tested in each of the following three dual-task experimental conditions, which were varying in complexity: (1 auditory word recognition + visual processing, (2 auditory working memory (word + visual processing, and (3 auditory working memory (sentence + visual processing in noise. Results: A repeated measures analysis of variance revealed that task complexity significantly affected the performance measures of auditory accuracy, visual accuracy, and processing speed. Linear regression revealed that the cognitive subtests of the WCJ-III test significantly predicted performance across dependent variable measures. Conclusion: Listening effort is significantly affected by task complexity, regardless of age. Performance on the WCJ-III test may predict listening effort in adults and may assist speech-language pathologist (SLPs to understand challenges faced by participants when subjected to noise.

  17. 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.

  18. PERFORMANCE ASSESSMENT FOR FIELD SPORTS

    Directory of Open Access Journals (Sweden)

    Christopher Carling

    2009-03-01

    Full Text Available DESCRIPTION The book covers the various sport science assessment procedures for sports such as soccer, rugby, field hockey and lacrosse. It provides detailed and clear information about laboratory and field-based methods that can be used to assess and improve both individual and team performance. PURPOSE The book aims to provide a contemporary reference tool for selection of appropriate testing procedures for sports across a range of scientific disciplines. FEATURES The text begins with a chapter on the rationales for performance assessments, the use of technology and the necessity for procedures to conform to scientific rigor, explaining the importance of test criteria. This chapter ends by emphasizing the importance of the feedback process and vital considerations for the practitioner when interpreting the data, selecting which information is most important and how to deliver this back to the athlete or coach in order to deliver a positive performance outcome. The next two chapters focus on psychological assessments with respect to skill acquisition, retention and execution providing a variety of qualitative and quantitative options, underpinned with scientific theory and contextualized in order to improve the understanding of the application of these methods to improve anticipation and decision-making to enhance game intelligence.Chapter 4 provides coverage of match analysis techniques in order to make assessments of technical, tactical and physical performances. Readers learn about a series of methodologies ranging from simplistic pen and paper options through to sophisticated technological systems with some exemplar data also provided. Chapters 5 through 7 cover the physiological based assessments, including aerobic, anaerobic and anthropometric procedures. Each chapter delivers a theoretical opening section before progressing to various assessment options and the authors make great efforts to relate to sport-specific settings. The final

  19. 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.

  20. The Effects of Differential Goal Weights on the Performance of a Complex Financial Task.

    Science.gov (United States)

    Edmister, Robert O.; Locke, Edwin A.

    1987-01-01

    Determined whether people could obtain outcomes on a complex task that would be in line with differential goal weights corresponding to different aspects of the task. Bank lending officers were run through lender-simulation exercises. Five performance goals were weighted. Demonstrated effectiveness of goal setting with complex tasks, using group…

  1. 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

    2012-01-01

    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…

  2. Waste isolation safety assessment program. Task 4. Third contractor information meeting

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    The Contractor Information Meeting (October 14 to 17, 1979) was part of the FY-1979 effort of Task 4 of the Waste Isolation Safety Assessment Program (WISAP): Sorption/Desorption Analysis. The objectives of this task are to: evaluate sorption/desorption measurement methods and develop a standardized measurement procedure; produce a generic data bank of nuclide-geologic interactions using a wide variety of geologic media and groundwaters; perform statistical analysis and synthesis of these data; perform validation studies to compare short-term laboratory studies to long-term in situ behavior; develop a fundamental understanding of sorption/desorption processes; produce x-ray and gamma-emitting isotopes suitable for the study of actinides at tracer concentrations; disseminate resulting information to the international technical community; and provide input data support for repository safety assessment. Conference participants included those subcontracted to WISAP Task 4, representatives and independent subcontractors to the Office of Nuclear Waste Isolation, representatives from other waste disposal programs, and experts in the area of waste/geologic media interaction. Since the meeting, WISAP has been divided into two programs: Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) (modeling efforts) and Waste/Rock Interactions Technology (WRIT) (experimental work). The WRIT program encompasses the work conducted under Task 4. This report contains the information presented at the Task 4, Third Contractor Information Meeting. Technical Reports from the subcontractors, as well as Pacific Northwest Laboratory (PNL), are provided along with transcripts of the question-and-answer sessions. The agenda and abstracts of the presentations are also included. Appendix A is a list of the participants. Appendix B gives an overview of the WRIT program and details the WRIT work breakdown structure for 1980.

  3. Waste isolation safety assessment program. Task 4. Third contractor information meeting

    International Nuclear Information System (INIS)

    1980-06-01

    The Contractor Information Meeting (October 14 to 17, 1979) was part of the FY-1979 effort of Task 4 of the Waste Isolation Safety Assessment Program (WISAP): Sorption/Desorption Analysis. The objectives of this task are to: evaluate sorption/desorption measurement methods and develop a standardized measurement procedure; produce a generic data bank of nuclide-geologic interactions using a wide variety of geologic media and groundwaters; perform statistical analysis and synthesis of these data; perform validation studies to compare short-term laboratory studies to long-term in situ behavior; develop a fundamental understanding of sorption/desorption processes; produce x-ray and gamma-emitting isotopes suitable for the study of actinides at tracer concentrations; disseminate resulting information to the international technical community; and provide input data support for repository safety assessment. Conference participants included those subcontracted to WISAP Task 4, representatives and independent subcontractors to the Office of Nuclear Waste Isolation, representatives from other waste disposal programs, and experts in the area of waste/geologic media interaction. Since the meeting, WISAP has been divided into two programs: Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) (modeling efforts) and Waste/Rock Interactions Technology (WRIT) (experimental work). The WRIT program encompasses the work conducted under Task 4. This report contains the information presented at the Task 4, Third Contractor Information Meeting. Technical Reports from the subcontractors, as well as Pacific Northwest Laboratory (PNL), are provided along with transcripts of the question-and-answer sessions. The agenda and abstracts of the presentations are also included. Appendix A is a list of the participants. Appendix B gives an overview of the WRIT program and details the WRIT work breakdown structure for 1980

  4. Framing of task performance strategies: effects on performance in a multiattribute dynamic decision making environment.

    Science.gov (United States)

    Nygren, T E

    1997-09-01

    It is well documented that the way a static choice task is "framed" can dramatically alter choice behavior, often leading to observable preference reversals. This framing effect appears to result from perceived changes in the nature or location of a person's initial reference point, but it is not clear how framing effects might generalize to performance on dynamic decision making tasks that are characterized by high workload, time constraints, risk, or stress. A study was conducted to examine the hypothesis that framing can introduce affective components to the decision making process and can influence, either favorably (positive frame) or adversely (negative frame), the implementation and use of decision making strategies in dynamic high-workload environments. Results indicated that negative frame participants were significantly impaired in developing and employing a simple optimal decision strategy relative to a positive frame group. Discussion focuses on implications of these results for models of dynamic decision making.

  5. 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.

  6. Effects of task performance, helping, voice, and organizational loyalty on performance appraisal ratings.

    Science.gov (United States)

    Whiting, Steven W; Podsakoff, Philip M; Pierce, Jason R

    2008-01-01

    Despite the fact that several studies have investigated the relationship between organizational citizenship behavior and performance appraisal ratings, the vast majority of these studies have been cross-sectional, correlational investigations conducted in organizational settings that do not allow researchers to establish the causal nature of this relationship. To address this lack of knowledge regarding causality, the authors conducted 2 studies designed to investigate the effects of task performance, helping behavior, voice, and organizational loyalty on performance appraisal evaluations. Findings demonstrated that each of these forms of behavior has significant effects on performance evaluation decisions and suggest that additional attention should be directed at both voice and organizational loyalty as important forms of citizenship behavior aimed at the organization. 2008 APA

  7. Absorbed in the task : Personality measures predict engagement during task performance as tracked by error negativity and asymmetrical frontal activity

    NARCIS (Netherlands)

    Tops, Mattie; Boksem, Maarten A. S.

    2010-01-01

    We hypothesized that interactions between traits and context predict task engagement, as measured by the amplitude of the error-related negativity (ERN), performance, and relative frontal activity asymmetry (RFA). In Study 1, we found that drive for reward, absorption, and constraint independently

  8. Swimming Pool Hygiene: Self-Monitoring, Task Clarification, and Performance Feedback Increase Lifeguard Cleaning Behaviors

    Science.gov (United States)

    Rose, Henry M. S.; Ludwig, Timothy D.

    2009-01-01

    The effects of task clarification, self-monitoring, and performance feedback on cleaning behaviors of 9 lifeguards in 3 performance areas (vacuuming, lobby tidying, and pool deck maintenance) were investigated using an ABA reversal design at a county swim complex. A specific task in each performance area was used as a behavioral control. Following…

  9. Children's Sleep, Sleepiness, and Performance on Cognitive Tasks.

    Science.gov (United States)

    Buckhalt, Joseph A

    2011-01-01

    While causal connections between sleep deprivation and attention, learning, and memory have been well established in adults, much less research has been done with children. Relations between the amount and quality of sleep and daytime sleepiness have been found for a number of cognitive and academic tasks in several groups of children. These relations have been found for children who have sleep disorders, for children with disorders involving cognitive impairment, and for typically developing children with no known disorders. The research is reviewed here with a focus on the types of cognitive and academic tasks that have been related to insufficient sleep. A series of studies is described that relates sleep parameters to the Woodcock-Johnson® III Tests of Cognitive Abilities and other, similar measures. Implications for educators and psychologists who work with children are discussed.

  10. Children's Sleep, Sleepiness, and Performance on Cognitive Tasks

    OpenAIRE

    Buckhalt, Joseph A.

    2011-01-01

    While causal connections between sleep deprivation and attention, learning, and memory have been well established in adults, much less research has been done with children. Relations between the amount and quality of sleep and daytime sleepiness have been found for a number of cognitive and academic tasks in several groups of children. These relations have been found for children who have sleep disorders, for children with disorders involving cognitive impairment, and for typically developing...

  11. Effect of a Body Model on Performance in a Virtual Environment Search Task

    National Research Council Canada - National Science Library

    Singer, Michael

    1998-01-01

    ...) in training dismounted soldiers. This experiment investigated full body representation (generic) versus a hand linked pointer on movement performance in an office building interior during a search task...

  12. Associations between physical function, dual-task performance and cognition in patients with mild Alzheimer's disease

    DEFF Research Database (Denmark)

    Sobol, Nanna Aue; Hoffmann, Kristine; Vogel, Asmus Mejling

    2016-01-01

    blinded multicenter RCT 'ADEX' (Alzheimer's disease: the effect of physical exercise) were used. Assessments included tests of physical function: 400-m walk test, 10-m walk test, Timed Up and Go test and 30-s chair stand test; dual-task performance, i.e., 10-m walk while counting backwards from 50...... or naming the months backwards; and cognition, i.e., Mini Mental State Examination, Symbol Digit Modalities Test, the Stroop Color and Word Test, and Lexical verbal fluency test. RESULTS: Results in the 30-s chair stand test correlated significantly with all tests of cognition (r = .208-.242) while...

  13. Assessment of driving after stroke--a pluridisciplinary task.

    Science.gov (United States)

    Ponsford, A-S; Viitanen, M; Lundberg, C; Johansson, K

    2008-03-01

    The aim of the study was to analyze the assessment procedure and identify predictors for the team decision when assessing fitness to drive a car after stroke. The material used was a retrospective data set with 200 stroke clients from Queen Elisabeth's Foundation Mobility Centre at Banstead UK. Fifty-four percent of clients were considered fit to continue driving where 9% could resume driving after car adaptation and training. Important factors for the outcome were vision (acuity and field), neuropsychological functions (divided attention), and track and/or on road test (reaction time, anticipation, speed, and positioning). Cognitive impairment was the main problem in those who failed the driving test and judged not fit for continued driving. Car adaptation, mainly comprising infrared transmitted secondary controls together with automatic transmission was recommended in 35% of the cases. The contribution of different specialist groups appears to be necessary for an effective evaluation, but the assessment procedure can be done more cost-effectively by dividing it into two separate parts and removing certain subtests. The in-car track test is an important part of the assessment procedure with a high face validity and could in many cases make it unnecessary to perform in-traffic tests with unsafe drivers. Car adaptation is often necessary for a client with pronounced hemi-paresis and a full road test can for those only be performed after training the use of car controls.

  14. Assessing Mental Models of Emergencies Through Two Knowledge Elicitation Tasks.

    Science.gov (United States)

    Whitmer, Daphne E; Sims, Valerie K; Torres, Michael E

    2017-05-01

    The goals of this study were to assess the risk identification aspect of mental models using standard elicitation methods and how university campus alerts were related to these mental models. People fail to follow protective action recommendations in emergency warnings. Past research has yet to examine cognitive processes that influence emergency decision-making. Study 1 examined 2 years of emergency alerts distributed by a large southeastern university. In Study 2, participants listed emergencies in a thought-listing task. Study 3 measured participants' time to decide if a situation was an emergency. The university distributed the most alerts about an armed person, theft, and fire. In Study 2, participants most frequently listed fire, car accident, heart attack, and theft. In Study 3, participants quickly decided a bomb, murder, fire, tornado, and rape were emergencies. They most slowly decided that a suspicious package and identify theft were emergencies. Recent interaction with warnings was only somewhat related to participants' mental models of emergencies. Risk identification precedes decision-making and applying protective actions. Examining these characteristics of people's mental representations of emergencies is fundamental to further understand why some emergency warnings go ignored. Someone must believe a situation is serious to categorize it as an emergency before taking the protective action recommendations in an emergency warning. Present-day research must continue to examine the problem of people ignoring warning communication, as there are important cognitive factors that have not yet been explored until the present research.

  15. 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)

  16. Staff Performance Analysis: A Method for Identifying Brigade Staff Tasks

    National Research Council Canada - National Science Library

    Ford, Laura

    1997-01-01

    ... members of conventional mounted brigade staff. Initial analysis of performance requirements in existing documentation revealed that the performance specifications were not sufficiently detailed for brigade battle staffs...

  17. Depressive symptoms and poorer performance on the Stroop Task are associated with weight gain.

    Science.gov (United States)

    Stinson, Emma J; Krakoff, Jonathan; Gluck, Marci E

    2018-03-15

    Executive function impairments and depression are associated with obesity but whether they predict weight gain is unclear. Forty-six individuals (35m, 37±10y) completed the Stroop Task, Iowa Gambling Task (IGT), Wisconsin Card Sorting Task (WCST), Inventory for Depressive Symptomatology (IDS-SR), Physical Anhedonia Scale (PAS), and Perceived Stress Scale (PSS). Body composition (DXA) and fasting glucose were also measured. Data from return visits were used to assess changes in weight. Poorer Stroop and WCST performance associated with higher BMI whereas poorer IGT and WCST performance associated with higher body fat (%; all p's≤0.05). Stroop interference (p=0.04; p=0.05) and IDS-SR (p=0.06; p=0.02) associated with increased BMI and weight gain (%/yr). In a multivariate linear model Stroop interference (β=0.40, p<0.01; β=0.35, p<0.01) and IDS-SR (β=0.38, p<0.01; β=0.37, p<0.01) independently predicted increased BMI and weight gain (%/yr) even after controlling for baseline weight and glucose levels. Poorer response inhibition and depressive symptoms, but not glucose levels, predicted weight gain. Evaluating neurocognitive and mood deficits could improve current treatment strategies for weight loss. Clinical Trial Registration Numbers NCT00523627, NCT00342732, NCT01224704. clinicaltrials.gov. Published by Elsevier Inc.

  18. Methodology for NDA performance assessment

    International Nuclear Information System (INIS)

    Cuypers, M.; Franklin, M.; Guardini, S.

    1986-01-01

    In the framework of the RandD programme of the Joint Research Centre of the Commission of the European Communities, a considerable effort is being dedicated to performance assessment of NDA techniques taking account of field conditions. By taking account of field conditions is meant measurement samples of the size encountered in practice and training which allows inspectors to design cost efficient verification plans for the real situations encountered in the field. Special laboratory facilities referred to as PERLA are being constructed for this purpose. These facilities will be used for measurement experiments and for training. In this paper, performance assessment is discussed under the headings of measurement capability and in-field effectiveness. Considerable emphasis is given to the role of method specific measurement error models. The authors outline the advantages of giving statistical error models a sounder basis in the physical phenomenology of the measurement method

  19. The effect analysis of mediation variable of task productivity on the self-efficacy and employees’ performance

    Directory of Open Access Journals (Sweden)

    Annissa Chairum Soebandono

    2016-11-01

    Full Text Available This research was conducted for analyzing the effect of mediating variable that is individual task proactivity as one of the proactivities of behavior towards the relationship between self-efficacy and the employees’ performance in the logistics companies of shipping the goods. It uses convenience sampling, which is a non-probability sampling method for getting the sample of 52 employees. They were divided into two divisions, namely infrastructure and quality assurance. The questionnaire consists of two parts, in which some were assessed by themselves and others that were assessed by the supervisor. They were analyzed using path analysis using analytical tools developed by Hayes, Preacher-Hayes with the simple mediation models. It was found that employees have self-efficacy, individual task proactivity, and relatively high performance, in which individual task proactivity can be a mediating variable on the effect self-efficacy on performance.

  20. Preliminary melter performance assessment report

    International Nuclear Information System (INIS)

    Elliott, M.L.; Eyler, L.L.; Mahoney, L.A.; Cooper, M.F.; Whitney, L.D.; Shafer, P.J.

    1994-08-01

    The Melter Performance Assessment activity, a component of the Pacific Northwest Laboratory's (PNL) Vitrification Technology Development (PVTD) effort, was designed to determine the impact of noble metals on the operational life of the reference Hanford Waste Vitrification Plant (HWVP) melter. The melter performance assessment consisted of several activities, including a literature review of all work done with noble metals in glass, gradient furnace testing to study the behavior of noble metals during the melting process, research-scale and engineering-scale melter testing to evaluate effects of noble metals on melter operation, and computer modeling that used the experimental data to predict effects of noble metals on the full-scale melter. Feed used in these tests simulated neutralized current acid waste (NCAW) feed. This report summarizes the results of the melter performance assessment and predicts the lifetime of the HWVP melter. It should be noted that this work was conducted before the recent Tri-Party Agreement changes, so the reference melter referred to here is the Defense Waste Processing Facility (DWPF) melter design

  1. Performance Assessment Institute-NV

    Energy Technology Data Exchange (ETDEWEB)

    Lombardo, Joesph [Univ. of Nevada, Las Vegas, NV (United States)

    2012-12-31

    The National Supercomputing Center for Energy and the Environment’s intention is to purchase a multi-purpose computer cluster in support of the Performance Assessment Institute (PA Institute). The PA Institute will serve as a research consortium located in Las Vegas Nevada with membership that includes: national laboratories, universities, industry partners, and domestic and international governments. This center will provide a one-of-a-kind centralized facility for the accumulation of information for use by Institutions of Higher Learning, the U.S. Government, and Regulatory Agencies and approved users. This initiative will enhance and extend High Performance Computing (HPC) resources in Nevada to support critical national and international needs in "scientific confirmation". The PA Institute will be promoted as the leading Modeling, Learning and Research Center worldwide. The program proposes to utilize the existing supercomputing capabilities and alliances of the University of Nevada Las Vegas as a base, and to extend these resource and capabilities through a collaborative relationship with its membership. The PA Institute will provide an academic setting for interactive sharing, learning, mentoring and monitoring of multi-disciplinary performance assessment and performance confirmation information. The role of the PA Institute is to facilitate research, knowledge-increase, and knowledge-sharing among users.

  2. 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.

  3. 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...

  4. Temporal Distinctiveness in Task Switching: Assessing the Mixture-Distribution Assumption

    Directory of Open Access Journals (Sweden)

    James A Grange

    2016-02-01

    Full Text Available In task switching, increasing the response--cue interval has been shown to reduce the switch cost. This has been attributed to a time-based decay process influencing the activation of memory representations of tasks (task-sets. Recently, an alternative account based on interference rather than decay has been successfully applied to this data (Horoufchin et al., 2011. In this account, variation of the RCI is thought to influence the temporal distinctiveness (TD of episodic traces in memory, thus affecting their retrieval probability. This can affect performance as retrieval probability influences response time: If retrieval succeeds, responding is fast due to positive priming; if retrieval fails, responding is slow, due to having to perform the task via a slow algorithmic process. This account---and a recent formal model (Grange & Cross, 2015---makes the strong prediction that all RTs are a mixture of one of two processes: a fast process when retrieval succeeds, and a slow process when retrieval fails. The present paper assesses the evidence for this mixture-distribution assumption in TD data. In a first section, statistical evidence for mixture-distributions is found using the fixed-point property test. In a second section, a mathematical process model with mixture-distributions at its core is fitted to the response time distribution data. Both approaches provide good evidence in support of the mixture-distribution assumption, and thus support temporal distinctiveness accounts of the data.

  5. Task-oriented quality assessment and adaptation in real-time mission critical video streaming applications

    Science.gov (United States)

    Nightingale, James; Wang, Qi; Grecos, Christos

    2015-02-01

    In recent years video traffic has become the dominant application on the Internet with global year-on-year increases in video-oriented consumer services. Driven by improved bandwidth in both mobile and fixed networks, steadily reducing hardware costs and the development of new technologies, many existing and new classes of commercial and industrial video applications are now being upgraded or emerging. Some of the use cases for these applications include areas such as public and private security monitoring for loss prevention or intruder detection, industrial process monitoring and critical infrastructure monitoring. The use of video is becoming commonplace in defence, security, commercial, industrial, educational and health contexts. Towards optimal performances, the design or optimisation in each of these applications should be context aware and task oriented with the characteristics of the video stream (frame rate, spatial resolution, bandwidth etc.) chosen to match the use case requirements. For example, in the security domain, a task-oriented consideration may be that higher resolution video would be required to identify an intruder than to simply detect his presence. Whilst in the same case, contextual factors such as the requirement to transmit over a resource-limited wireless link, may impose constraints on the selection of optimum task-oriented parameters. This paper presents a novel, conceptually simple and easily implemented method of assessing video quality relative to its suitability for a particular task and dynamically adapting videos streams during transmission to ensure that the task can be successfully completed. Firstly we defined two principle classes of tasks: recognition tasks and event detection tasks. These task classes are further subdivided into a set of task-related profiles, each of which is associated with a set of taskoriented attributes (minimum spatial resolution, minimum frame rate etc.). For example, in the detection class

  6. Gaze training enhances laparoscopic technical skill acquisition and multi-tasking performance: a randomized, controlled study.

    Science.gov (United States)

    Wilson, Mark R; Vine, Samuel J; Bright, Elizabeth; Masters, Rich S W; Defriend, David; McGrath, John S

    2011-12-01

    The operating room environment is replete with stressors and distractions that increase the attention demands of what are already complex psychomotor procedures. Contemporary research in other fields (e.g., sport) has revealed that gaze training interventions may support the development of robust movement skills. This current study was designed to examine the utility of gaze training for technical laparoscopic skills and to test performance under multitasking conditions. Thirty medical trainees with no laparoscopic experience were divided randomly into one of three treatment groups: gaze trained (GAZE), movement trained (MOVE), and discovery learning/control (DISCOVERY). Participants were fitted with a Mobile Eye gaze registration system, which measures eye-line of gaze at 25 Hz. Training consisted of ten repetitions of the "eye-hand coordination" task from the LAP Mentor VR laparoscopic surgical simulator while receiving instruction and video feedback (specific to each treatment condition). After training, all participants completed a control test (designed to assess learning) and a multitasking transfer test, in which they completed the procedure while performing a concurrent tone counting task. Not only did the GAZE group learn more quickly than the MOVE and DISCOVERY groups (faster completion times in the control test), but the performance difference was even more pronounced when multitasking. Differences in gaze control (target locking fixations), rather than tool movement measures (tool path length), underpinned this performance advantage for GAZE training. These results suggest that although the GAZE intervention focused on training gaze behavior only, there were indirect benefits for movement behaviors and performance efficiency. Additionally, focusing on a single external target when learning, rather than on complex movement patterns, may have freed-up attentional resources that could be applied to concurrent cognitive tasks.

  7. The effect of simultaneously performed cognitive task and physical exercise on pressure pain threshold and tolerance in athletes

    Directory of Open Access Journals (Sweden)

    Aliye GÜNDOĞDU

    2014-08-01

    Full Text Available The aim of the study was to investigate the alterations of the pain threshold and tolerance after single, or dual task in athletes. Twenty male athletes and twenty non - athletic, recreationally active college students were participated in the study. Subjects w ere asked to perform Harvard step test (single task, and cognitive task was concurrent performance of an arithmetic task while performing Harvard step test. Pressure pain threshold (PPT and pressure pain tolerance (PPTO were assessed from muscle, tendon , bone and myofascial region from the dominant thigh by using a digital algometer. All measurements were repeated at rest, or following single and dual task. Results are presented as mean + standart deviation. Data were analyzed by using repeated measures of ANOVA test. A level of p<0.05 was accepted statistical significant. Athletes had higher PPT and PPTO measurements from muscle and myofascial region of thigh at rest. PPT and PPTO values were increased after single, or dual task in sedentary subjects, w hile athletic subjects had increased muscle and myofascial PPT and PPTO values after dual task. In conclusion, our results supports the notion that cognitive functions may interact the pain processing at rest, or following exercise in athletes.

  8. Exploring the Performance Differences on the Flicker Task and the Conners' Continuous Performance Test in Adults with ADHD

    Science.gov (United States)

    Cohen, Andrew L.; Shapiro, Steven K.

    2007-01-01

    Objective: To examine the ability of the flicker task to demonstrate greater utility in discriminating performance in young adults with and without ADHD compared to the Conners' CPT (CCPT). Method: Flicker task and CCPT performance were compared between an ADHD (n = 28) and control (n = 30) group of college students. Results: This study replicated…

  9. Current status of the tasks performed by the Nuclear Fuel Department for the CAREM project

    International Nuclear Information System (INIS)

    Kaufmann, Federico; Perez, Lidia E.; Perez, Aaldo; Marchi, Daniel E.

    2009-01-01

    CAREM Project required to the Nuclear Fuels Department to perform the necessary tasks to define the powder characteristics and natural UO 2 -Gd 2 O 3 , UO 2 -1.8 and 3.1 % enrichment fuel pellets manufacturing and control parameters. To start with these tasks it was necessary to hire and train staff, begin the licensing process of the facilities, update infrastructure works and equipment of existing facilities. A brief description of the tasks performed is shown. (author)

  10. Effects of Gait Self-Efficacy and Lower-Extremity Physical Function on Dual-Task Performance in Older Adults

    Science.gov (United States)

    Banducci, Sarah E.; Daugherty, Ana M.; Fanning, Jason; Awick, Elizabeth A.; Porter, Gwenndolyn C.; Burzynska, Agnieszka; Shen, Sa; Kramer, Arthur F.; McAuley, Edward

    2017-01-01

    Objectives. Despite evidence of self-efficacy and physical function's influences on functional limitations in older adults, few studies have examined relationships in the context of complex, real-world tasks. The present study tested the roles of self-efficacy and physical function in predicting older adults' street-crossing performance in single- and dual-task simulations. Methods. Lower-extremity physical function, gait self-efficacy, and street-crossing success ratio were assessed in 195 older adults (60–79 years old) at baseline of a randomized exercise trial. During the street-crossing task, participants walked on a self-propelled treadmill in a virtual reality environment. Participants crossed the street without distraction (single-task trials) and conversed on a cell phone (dual-task trials). Structural equation modeling was used to test hypothesized associations independent of demographic and clinical covariates. Results. Street-crossing performance was better on single-task trials when compared with dual-task trials. Direct effects of self-efficacy and physical function on success ratio were observed in dual-task trials only. The total effect of self-efficacy was significant in both conditions. The indirect path through physical function was evident in the dual-task condition only. Conclusion. Physical function can predict older adults' performance on high fidelity simulations of complex, real-world tasks. Perceptions of function (i.e., self-efficacy) may play an even greater role. The trial is registered with United States National Institutes of Health ClinicalTrials.gov (ID: NCT01472744; Fit & Active Seniors Trial). PMID:28255557

  11. Is the Use of Information and Communication Technology Related to Performance in Working Memory Tasks? Evidence from Seventh-Grade Students

    Science.gov (United States)

    Garcia, Lucy; Nussbaum, Miguel; Preiss, David D.

    2011-01-01

    The main purpose of this study was to assess whether seventh-grade students use of information and communication technology (ICT) was related to performance on working memory tasks. In addition, the study tested whether the relationship between ICT use and performance on working memory tasks interacted with seventh-grade students' socioeconomic…

  12. Effect of aging on performance, muscle activation and perceived stress during mentally demanding computer tasks

    DEFF Research Database (Denmark)

    Alkjaer, Tine; Pilegaard, Marianne; Bakke, Merete

    2005-01-01

    OBJECTIVES: This study examined the effects of age on performance, muscle activation, and perceived stress during computer tasks with different levels of mental demand. METHODS: Fifteen young and thirteen elderly women performed two computer tasks [color word test and reference task] with different...... levels of mental demand but similar physical demands. The performance (clicking frequency, percentage of correct answers, and response time for correct answers) and electromyography from the forearm, shoulder, and neck muscles were recorded. Visual analogue scales were used to measure the participants......' perception of the stress and difficulty related to the tasks. RESULTS: Performance decreased significantly in both groups during the color word test in comparison with performance on the reference task. However, the performance reduction was more pronounced in the elderly group than in the young group...

  13. Understanding the Effects of Long-duration Space Flight on Astronant Functional Task Performance

    Science.gov (United States)

    Bloomberg, Jacob J.; Batson, Crystal D.; Buxton, Roxanne E.; Feiveson, Al H.; Kofman, Igor S.; Lee, Stuart M. C.; Miller, Chris A.; Mulavara, Ajitkumar P.; Peters, Brian T.; Phillips, Tiffany; hide

    2014-01-01

    Space flight is known to cause alterations in multiple physiological systems including changes in sensorimotor, cardiovascular, and neuromuscular systems. These physiological changes cause balance, gait and visual disturbances, cardiovascular deconditioning, and loss of muscle mass and strength. These changes may affect a crewmember's ability to perform critical mission tasks immediately after landing on a planetary surface. To understand how changes in physiological function affect functional performance, an interdisciplinary pre- and postflight testing regimen, Functional Task Test (FTT), was developed to systematically evaluate both astronaut functional performance and related physiological changes. Ultimately this information will be used to assess performance risks and inform the design of countermeasures for exploration class missions. We are currently conducting the FTT study on International Space Station (ISS) crewmembers before and after 6-month expeditions. Additionally, in a corresponding study we are using the FTT protocol on subjects before and after 70 days of 6deg head-down bed-rest as an analog for space flight. Bed-rest provides the opportunity for us to investigate the role of prolonged axial body unloading in isolation from the other physiological effects produced by exposure to the microgravity environment of space flight. Therefore, the bed rest analog allows us to investigate the impact of body unloading on both functional tasks and on the underlying physiological factors that lead to decrement in performance and then compare them with the results obtained in our space flight study. Functional tests included ladder climbing, hatch opening, jump down, manual manipulation of objects and tool use, seat egress and obstacle avoidance, recovery from a fall and object translation tasks. Physiological measures included assessments of postural and gait control, dynamic visual acuity, fine motor control, plasma volume, heart rate, blood pressure

  14. 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.

  15. 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.

  16. 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.

  17. The effects of bedrest on crew performance during simulated shuttle reentry. Volume 2: Control task performance

    Science.gov (United States)

    Jex, H. R.; Peters, R. A.; Dimarco, R. J.; Allen, R. W.

    1974-01-01

    A simplified space shuttle reentry simulation performed on the NASA Ames Research Center Centrifuge is described. Anticipating potentially deleterious effects of physiological deconditioning from orbital living (simulated here by 10 days of enforced bedrest) upon a shuttle pilot's ability to manually control his aircraft (should that be necessary in an emergency) a comprehensive battery of measurements was made roughly every 1/2 minute on eight military pilot subjects, over two 20-minute reentry Gz vs. time profiles, one peaking at 2 Gz and the other at 3 Gz. Alternate runs were made without and with g-suits to test the help or interference offered by such protective devices to manual control performance. A very demanding two-axis control task was employed, with a subcritical instability in the pitch axis to force a high attentional demand and a severe loss-of-control penalty. The results show that pilots experienced in high Gz flying can easily handle the shuttle manual control task during 2 Gz or 3 Gz reentry profiles, provided the degree of physiological deconditioning is no more than induced by these 10 days of enforced bedrest.

  18. 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)

  19. Cognitive Load Theory: An Empirical Study of Anxiety and Task Performance in Language Learning

    Science.gov (United States)

    Chen, I-Jung; Chang, Chi-Cheng

    2009-01-01

    Introduction: This study explores the relationship among three variables--cognitive load, foreign language anxiety, and task performance. Cognitive load refers to the load imposed on working memory while performing a particular task. The authors hypothesized that anxiety consumes the resources of working memory, leaving less capacity for cognitive…

  20. Effects of Mindfulness-Based Intervention to Improve Task Performance for Children with Intellectual Disabilities

    Science.gov (United States)

    Kim, Jeongil; Kwon, Miyoung

    2018-01-01

    Background: Task performance is a critical factor for learning in individuals with intellectual disabilities. This study aimed to examine mindfulness-based intervention (MBI) to improve task performance for children with intellectual disability (ID). Methods: Three elementary school children with ID participated in the study. A multiple baseline…

  1. 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

  2. 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.

  3. Decision criterion dynamics in animals performing an auditory detection task.

    Directory of Open Access Journals (Sweden)

    Robert W Mill

    Full Text Available Classical signal detection theory attributes bias in perceptual decisions to a threshold criterion, against which sensory excitation is compared. The optimal criterion setting depends on the signal level, which may vary over time, and about which the subject is naïve. Consequently, the subject must optimise its threshold by responding appropriately to feedback. Here a series of experiments was conducted, and a computational model applied, to determine how the decision bias of the ferret in an auditory signal detection task tracks changes in the stimulus level. The time scales of criterion dynamics were investigated by means of a yes-no signal-in-noise detection task, in which trials were grouped into blocks that alternately contained easy- and hard-to-detect signals. The responses of the ferrets implied both long- and short-term criterion dynamics. The animals exhibited a bias in favour of responding "yes" during blocks of harder trials, and vice versa. Moreover, the outcome of each single trial had a strong influence on the decision at the next trial. We demonstrate that the single-trial and block-level changes in bias are a manifestation of the same criterion update policy by fitting a model, in which the criterion is shifted by fixed amounts according to the outcome of the previous trial and decays strongly towards a resting value. The apparent block-level stabilisation of bias arises as the probabilities of outcomes and shifts on single trials mutually interact to establish equilibrium. To gain an intuition into how stable criterion distributions arise from specific parameter sets we develop a Markov model which accounts for the dynamic effects of criterion shifts. Our approach provides a framework for investigating the dynamics of decisions at different timescales in other species (e.g., humans and in other psychological domains (e.g., vision, memory.

  4. Salt site performance assessment activities

    International Nuclear Information System (INIS)

    Kircher, J.F.; Gupta, S.K.

    1983-01-01

    During this year the first selection of the tools (codes) for performance assessments of potential salt sites have been tentatively selected and documented; the emphasis has shifted from code development to applications. During this period prior to detailed characterization of a salt site, the focus is on bounding calculations, sensitivity and with the data available. The development and application of improved methods for sensitivity and uncertainty analysis is a focus for the coming years activities and the subject of a following paper in these proceedings. Although the assessments to date are preliminary and based on admittedly scant data, the results indicate that suitable salt sites can be identified and repository subsystems designed which will meet the established criteria for protecting the health and safety of the public. 36 references, 5 figures, 2 tables

  5. Assessment Engineering Task Model Maps, Task Models and Templates as a New Way to Develop and Implement Test Specifications

    Science.gov (United States)

    Luecht, Richard M.

    2013-01-01

    Assessment engineering is a new way to design and implement scalable, sustainable and ideally lower-cost solutions to the complexities of designing and developing tests. It represents a merger of sorts between cognitive task modeling and engineering design principles--a merger that requires some new thinking about the nature of score scales, item…

  6. 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.

  7. Why Do Students Choose Not to Follow All Instructions When Completing Assessment Tasks?

    Science.gov (United States)

    Fleet, Wendy

    2013-01-01

    As academics we often assume that allocating marks to a task will influence student decision-making when it comes to completing that task. Marks are used by lecturers to indicate the relative importance of each of the criteria used for marking the assessment task and we expect the student to respond to the marks' allocation. This Postcard suggests…

  8. Assessing and Increasing Staff Preference for Job Tasks Using Concurrent-Chains Schedules and Probabilistic Outcomes

    Science.gov (United States)

    Reed, Derek D.; DiGennaro Reed, Florence D.; Campisano, Natalie; Lacourse, Kristen; Azulay, Richard L.

    2012-01-01

    The assessment and improvement of staff members' subjective valuation of nonpreferred work tasks may be one way to increase the quality of staff members' work life. The Task Enjoyment Motivation Protocol (Green, Reid, Passante, & Canipe, 2008) provides a process for supervisors to identify the aversive qualities of nonpreferred job tasks.…

  9. Merging assistance function with task distribution model to enhance user performance in collaborative virtual environment

    International Nuclear Information System (INIS)

    Khalid, S.; Alam, A.

    2016-01-01

    Collaborative Virtual Environments (CVEs) falls under Virtual Reality (VR) where two or more users manipulate objects collaboratively. In this paper we have made some experiments to make assembly from constituents parts scattered in Virtual Environment (VE) based on task distribution model using assistance functions for checking and enhancing user performance. The CVEs subjects setting on distinct connected machines via local area network. In this perspective, we consider the effects of assistance function with oral communication on collaboration, co-presence and users performance. Twenty subjects performed collaboratively an assembly task on static and dynamic based task distribution. We examine the degree of influence of assistance function with oral communications on user's performance based on task distribution model. The results show that assistance functions with oral communication based on task distribution model not only increase user performance but also enhance the sense of copresence and awareness. (author)

  10. 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.

  11. ASSESSING INDIVIDUAL PERFORMANCE ON INFORMATION TECHNOLOGY ADOPTION: A NEW MODEL

    OpenAIRE

    Diah Hari Suryaningrum

    2012-01-01

    This paper aims to propose a new model in assessing individual performance on information technology adoption. The new model to assess individual performance was derived from two different theories: decomposed theory of planned behavior and task-technology fit theory. Although many researchers have tried to expand these theories, some of their efforts might lack of theoretical assumptions. To overcome this problem and enhance the coherence of the integration, I used a theory from social scien...

  12. Effect of temperature on task performance in officeenvironment

    Energy Technology Data Exchange (ETDEWEB)

    Seppanen, Olli; Fisk, William J.; Lei, Q.H.

    2006-07-01

    Indoor temperature is one of the fundamental characteristics of the indoor environment. It can be controlled with a degree of accuracy dependent on the building and its HVAC system. The indoor temperature affects several human responses, including thermal comfort, perceived air quality, sick building syndrome symptoms and performance at work. In this study, we focused on the effects of temperature on performance at office work. We included those studies that had used objective indicators of performance that are likely to be relevant in office type work, such as text processing, simple calculations (addition, multiplication), length of telephone customer service time, and total handling time per customer for call-center workers. We excluded data from studies of industrial work performance. We calculated from all studies the percentage of performance change per degree increase in temperature, and statistically analyzed measured work performance with temperature. The results show that performance increases with temperature up to 21-22 C, and decreases with temperature above 23-24 C. The highest productivity is at temperature of around 22 C. For example, at the temperature of 30 C, the performance is only 91.1% of the maximum i.e. the reduction in performance is 8.9%

  13. The DECADE performance assessment program

    International Nuclear Information System (INIS)

    Weber, B.V.; Ottinger, P.F.; Commisso, R.J.; Thompson, J.; Rowley, J.E.; Filios, P.; Babineau, M.A.

    1996-01-01

    Previous analyses of DECADE Module 1 experiments indicated significant current loss between the plasma opening switch (POS) and an electron-beam load. A program was initiated to diagnose and improve the power flow to assess the performance of a multi-module DECADE system. Power flow measurements between the POS and load indicate high vacuum flow, distributed current loss and azimuthal asymmetries. A decreased load impedance reduces the fraction of the load current flowing in vacuum. Improved plasma source symmetry reduces losses near the load for long conduction times. Increased POS impedance is required to significantly improve the power coupling to the load. (author). 6 figs., 9 refs

  14. The DECADE performance assessment program

    Energy Technology Data Exchange (ETDEWEB)

    Weber, B V; Ottinger, P F; Commisso, R J [Naval Research Lab., Washington, DC (United States). Plasma Physics Div.; Goyer, J R; Kortbawi, D [Physics International Co., Berkeley, CA (United States); Thompson, J [Maxwell Labs., San Diego, CA (United States); Rowley, J E; Filios, P [Defense Nuclear Agency, Alexandria, VA (United States); Babineau, M A [Sverdlup Technology, Tullahoma, TN (United States)

    1997-12-31

    Previous analyses of DECADE Module 1 experiments indicated significant current loss between the plasma opening switch (POS) and an electron-beam load. A program was initiated to diagnose and improve the power flow to assess the performance of a multi-module DECADE system. Power flow measurements between the POS and load indicate high vacuum flow, distributed current loss and azimuthal asymmetries. A decreased load impedance reduces the fraction of the load current flowing in vacuum. Improved plasma source symmetry reduces losses near the load for long conduction times. Increased POS impedance is required to significantly improve the power coupling to the load. (author). 6 figs., 9 refs.

  15. Performance assessment of coupled processes

    International Nuclear Information System (INIS)

    Pigford, T.H.

    1987-01-01

    The author considers all processes to be coupled. For example, a waste package heats the surrounding rock and its pore water, creating gradients in density and pressure that result in increased water flow. That process can be described as coupled, in that the flow is a consequence of heating. In a narrower sense, one speaks also of the more weakly coupled transport processes, expressed by the Onsager reciprocal relations, that state that a transport current, i.e., flux, of heat is accompanied by a small transport current of material, as evidenced in isotope separation by thermal diffusion, the Thompson effect in thermoelectricity, etc. This paper presents a performance assessment of coupled processes

  16. Age-related neural correlates of cognitive task performance under increased postural load

    NARCIS (Netherlands)

    Van Impe, A; Bruijn, S M; Coxon, J P; Wenderoth, N; Sunaert, S; Duysens, J; Swinnen, S P

    2013-01-01

    Behavioral studies suggest that postural control requires increased cognitive control and visuospatial processing with aging. Consequently, performance can decline when concurrently performing a postural and a demanding cognitive task. We aimed to identify the neural substrate underlying this

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

    NARCIS (Netherlands)

    de Dreu, C.K.W.; Weingart, L.R.

    2003-01-01

    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, resultsrevealed strong and negative correlations between relationship conflict, team performance, and

  18. Detection of auditory signals in quiet and noisy backgrounds while performing a visuo-spatial task

    Directory of Open Access Journals (Sweden)

    Vishakha W Rawool

    2016-01-01

    Full Text Available Context: The ability to detect important auditory signals while performing visual tasks may be further compounded by background chatter. Thus, it is important to know how task performance may interact with background chatter to hinder signal detection. Aim: To examine any interactive effects of speech spectrum noise and task performance on the ability to detect signals. Settings and Design: The setting was a sound-treated booth. A repeated measures design was used. Materials and Methods: Auditory thresholds of 20 normal adults were determined at 0.5, 1, 2 and 4 kHz in the following conditions presented in a random order: (1 quiet with attention; (2 quiet with a visuo-spatial task or puzzle (distraction; (3 noise with attention and (4 noise with task. Statistical Analysis: Multivariate analyses of variance (MANOVA with three repeated factors (quiet versus noise, visuo-spatial task versus no task, signal frequency. Results: MANOVA revealed significant main effects for noise and signal frequency and significant noise–frequency and task–frequency interactions. Distraction caused by performing the task worsened the thresholds for tones presented at the beginning of the experiment and had no effect on tones presented in the middle. At the end of the experiment, thresholds (4 kHz were better while performing the task than those obtained without performing the task. These effects were similar across the quiet and noise conditions. Conclusion: Detection of auditory signals is difficult at the beginning of a distracting visuo-spatial task but over time, task learning and auditory training effects can nullify the effect of distraction and may improve detection of high frequency sounds.

  19. Measuring treatment effects on dual-task performance: a framework for research and clinical practice

    Directory of Open Access Journals (Sweden)

    Prudence ePlummer

    2015-04-01

    Full Text Available The relevance of dual-task walking to everyday ambulation is widely acknowledged, and numerous studies have demonstrated that dual-task interference can significantly impact recovery of functional walking in people with neurological disorders. The magnitude and direction of dual-task interference is influenced by the interaction between the two tasks, including how individuals spontaneously prioritize their attention. Therefore, to accurately interpret and characterize dual-task interference and identify changes over time, it is imperative to evaluate single and dual-task performance in both tasks, as well as the tasks relative to each other. Yet, reciprocal dual-task effects are frequently ignored. The purpose of this perspective paper is to present a framework for measuring treatment effects on dual-task interference, specifically taking into account the interactions between the two tasks and how this can provide information on whether overall dual-task capacity has improved or a different attentional strategy has been adopted. In discussing the clinical implications of using this framework, we provide specific examples of using this method and provide some explicit recommendations for research and clinical practice.

  20. Goal Setting and Task Performance: 1969-1980

    Science.gov (United States)

    1980-06-01

    self - esteem showed greater performance improvement than individuals with low self - esteem ...There was no self - esteem effect when instrumentality was high. When self - esteem was low , typists who perceived high goal instrumentality showed greater...performance improvement than M. 49 those with low goal instrumentality; when self - esteem was high, there was no instrumentality effect.

  1. Work Functioning Among Firefighters: A Comparison Between Self-Reported Limitations and Functional Task Performance.

    Science.gov (United States)

    MacDermid, Joy C; Tang, Kenneth; Sinden, Kathryn E; D'Amico, Robert

    2018-05-25

    Purpose Performance-based and disease indicators have been widely studied in firefighters; self-reported work role limitations have not. The aim of this study was to describe the distributions and correlations of a generic self-reported Work Limitations Questionnaire (WLQ-26) and firefighting-specific task performance-based tests. Methods Active firefighters from the City of Hamilton Fire Services (n = 293) were recruited. Participants completed the WLQ-26 to quantify on-the-job difficulties over five work domains: work scheduling (4 items), output demands (7 items), physical demands (8 items), mental demands (4 items), and social demands (3 items). A subset of participants (n = 149) were also assessed on hose drag and stair climb with a high-rise pack performance-based tests. Descriptive statistics and correlations were used to compare item/subscale performance; and to describe the inter-relationships between tests. Results The mean WLQ-26 item scores (/5) ranged from 4.1 to 4.4 (median = 5 for all items); most firefighters (54.5-80.5%) selected "difficult none of the time" response option on all items. A substantial ceiling effect was observed across all five WLQ-26 subscales as 44.0-55.6% were in the highest category. Subscale means ranged from 61.8 (social demands) to 78.7 (output demands and physical demands). Internal consistency exceeded 0.90 on all subscales. For the hose drag task, the mean time-to-completion was 48.0 s (SD = 14.5; range 20.4-95.0). For the stair climb task, the mean time-to-completion was 76.7 s (SD = 37.2; range 21.0-218.0). There were no significant correlations between self-report work limitations and performance of firefighting tasks. Conclusions The WLQ-26 measured five domains, but had ceiling effects in firefighters. Performance-based testing showed wider score range, lacked ceiling effects and did not correlate to the WLQ-26. A firefighter-specific, self-report role functioning scale may be needed to identify

  2. DECOVALEX III PROJECT. Thermal-Hydro-Mechanical Coupled Processes in Safety Assessments. Report of Task 4

    International Nuclear Information System (INIS)

    Andersson, Johan

    2005-02-01

    A part (Task 4) of the International DECOVALEX III project on coupled thermo-hydro-mechanical (T-H-M) processes focuses on T-H-M modelling applications in safety and performance assessment of deep geological nuclear waste repositories. A previous phase, DECOVALEX II, saw a need to improve such modelling. In order to address this need Task 4 of DECOVALEX III has: Analysed two major T-H-M experiments (Task 1 and Task 2) and three different Bench Mark Tests (Task 3) set-up to explore the significance of T-H-M in some potentially important safety assessment applications. Compiled and evaluated the use of T-H-M modelling in safety assessments at the time of the year 2000. Organised a forum a forum of interchange between PA-analysts and THM modelers at each DECOVALEX III workshop. Based on this information the current report discusses the findings and strives for reaching recommendations as regards good practices in addressing coupled T-H-M issues in safety assessments. The full development of T-H-M modelling is still at an early stage and it is not evident whether current codes provide the information that is required. However, although the geosphere is a system of fully coupled processes, this does not directly imply that all existing coupled mechanisms must be represented numerically. Modelling is conducted for specific purposes and the required confidence level should be considered. It is necessary to match the confidence level with the modelling objective. Coupled THM modelling has to incorporate uncertainties. These uncertainties mainly concern uncertainties in the conceptual model and uncertainty in data. Assessing data uncertainty is important when judging the need to model coupled processes. Often data uncertainty is more significant than the coupled effects. The emphasis on the need for THM modelling differs among disciplines. For geological radioactive waste disposal in crystalline and other similar hard rock formations DECOVALEX III shows it is essential to

  3. DECOVALEX III PROJECT. Thermal-Hydro-Mechanical Coupled Processes in Safety Assessments. Report of Task 4

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan [JA Streamflow AB, Aelvsjoe (Sweden)

    2005-02-15

    A part (Task 4) of the International DECOVALEX III project on coupled thermo-hydro-mechanical (T-H-M) processes focuses on T-H-M modelling applications in safety and performance assessment of deep geological nuclear waste repositories. A previous phase, DECOVALEX II, saw a need to improve such modelling. In order to address this need Task 4 of DECOVALEX III has: Analysed two major T-H-M experiments (Task 1 and Task 2) and three different Bench Mark Tests (Task 3) set-up to explore the significance of T-H-M in some potentially important safety assessment applications. Compiled and evaluated the use of T-H-M modelling in safety assessments at the time of the year 2000. Organised a forum a forum of interchange between PA-analysts and THM modelers at each DECOVALEX III workshop. Based on this information the current report discusses the findings and strives for reaching recommendations as regards good practices in addressing coupled T-H-M issues in safety assessments. The full development of T-H-M modelling is still at an early stage and it is not evident whether current codes provide the information that is required. However, although the geosphere is a system of fully coupled processes, this does not directly imply that all existing coupled mechanisms must be represented numerically. Modelling is conducted for specific purposes and the required confidence level should be considered. It is necessary to match the confidence level with the modelling objective. Coupled THM modelling has to incorporate uncertainties. These uncertainties mainly concern uncertainties in the conceptual model and uncertainty in data. Assessing data uncertainty is important when judging the need to model coupled processes. Often data uncertainty is more significant than the coupled effects. The emphasis on the need for THM modelling differs among disciplines. For geological radioactive waste disposal in crystalline and other similar hard rock formations DECOVALEX III shows it is essential to

  4. Human footprint variation while performing load bearing tasks.

    Directory of Open Access Journals (Sweden)

    Cara M Wall-Scheffler

    Full Text Available Human footprint fossils have provided essential evidence about the evolution of human bipedalism as well as the social dynamics of the footprint makers, including estimates of speed, sex and group composition. Generally such estimates are made by comparing footprint evidence with modern controls; however, previous studies have not accounted for the variation in footprint dimensions coming from load bearing activities. It is likely that a portion of the hominins who created these fossil footprints were carrying a significant load, such as offspring or foraging loads, which caused variation in the footprint which could extend to variation in any estimations concerning the footprint's maker. To identify significant variation in footprints due to load-bearing tasks, we had participants (N = 30, 15 males and 15 females walk at a series of speeds carrying a 20kg pack on their back, side and front. Paint was applied to the bare feet of each participant to create footprints that were compared in terms of foot length, foot width and foot area. Female foot length and width increased during multiple loaded conditions. An appreciation of footprint variability associated with carrying loads adds an additional layer to our understanding of the behavior and morphology of extinct hominin populations.

  5. 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

  6. Uncovering the relationship between transformational leaders and followers' task performance.

    NARCIS (Netherlands)

    Breevaart, K.; Bakker, A. B.; Demerouti, E.; Sleebos, D. M.; Maduro, V.

    2015-01-01

    The purpose of the present study was to unravel the mechanisms underlying the relationship between transformational leadership, follower work engagement, and follower job performance and to investigate a possible boundary condition of transformational leadership. We used structural equation modeling

  7. Computational Modeling of Human Multiple-Task Performance

    National Research Council Canada - National Science Library

    Kieras, David E; Meyer, David

    2005-01-01

    This is the final report for a project that was a continuation of an earlier, long-term project on the development and validation of the EPIC cognitive architecture for modeling human cognition and performance...

  8. An initial test of a normative Figure Of Merit for the quality of overall task performance

    Science.gov (United States)

    Lemay, Moira; Comstock, J. R., Jr.

    1990-01-01

    An overall indicator, or Figure Of Merit (FOM), of the quality of crew/vehicle system performance is needed to establish the effect of workload on efficiency and to identify overload conditions. A normative FOM is proposed in which performance is measured on a representative task and a normative data base obtained. FOMs for subsequent executions of the task are then reported in terms of weighted deviations from average task performance. Performance of discrete tasks is measured primarily in terms of subtask time and errors. Discrete task performance is then combined with a measure of continuous vehicle control. In order to test the normative FOM procedure, the technique was applied to an existing set of data from a simulated landing task in which standard communications with ATC was compared with a data link communications system. The results indicated that while mean task performance was not affected, task variability, as measured by the FOM, was significantly higher when data link communications were used. In order to establish the sensitivity of the normative FOM method, further testing of the measure is recommended.

  9. Modeling Operator Performance in Low Task Load Supervisory Domains

    Science.gov (United States)

    2011-06-01

    important to model the best and 65 worst performers separately. It is easy to see that the best performers were better multitaskers and more directed...the expected population this research will influence is expected to contain men and women between the ages of 18 and 50 with an interest in using...for your patience and great sense of humor. I could not ask for a better thesis reader. Thank you, Amy D’Agostino, for taking the time to read my

  10. Designing Second Language Performance Assessments. Technical Report.

    Science.gov (United States)

    Norris, John M.; Brown, James Dean; Hudson, Thom; Yoshioka, Jim

    This technical report focuses on the decision-making potential provided by second language performance assessments. First, performance assessment is situated within the broader discussion of alternatives in language assessment and in educational assessment in general. Next, issues in performance assessment design, implementation, reliability, and…

  11. 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.

  12. Task-focused behavior mediates the associations between supportive interpersonal environments and students' academic performance.

    Science.gov (United States)

    Kiuru, Noona; Pakarinen, Eija; Vasalampi, Kati; Silinskas, Gintautas; Aunola, Kaisa; Poikkeus, Anna-Maija; Metsäpelto, Riitta-Leena; Lerkkanen, Marja-Kristiina; Nurmi, Jari-Erik

    2014-04-01

    In the longitudinal study presented here, we tested the theoretical assumption that children's task-focused behavior in learning situations mediates the associations between supportive interpersonal environments and academic performance. The sample consisted of 2,137 Finnish-speaking children. Data on supportive interpersonal environments (characterized by authoritative parenting, positive teacher affect toward the child, and peer acceptance) were gathered in Grade 1. The children's task-focused behavior was measured in Grades 2 and 3, and academic performance was measured in Grades 1 and 4. The results supported our assumption by showing that all three supportive environments were positively associated with children's subsequent academic performance via increased task-focused behavior in learning situations. These findings suggest that students' academic performance can be promoted by increasing the support they receive from peers, parents, and teachers because such increased support leads to better task focus in learning tasks.

  13. Quality assurance in performance assessments

    International Nuclear Information System (INIS)

    Maul, P.R.; Watkins, B.M.; Salter, P.; Mcleod, R

    1999-01-01

    Following publication of the Site-94 report, SKI wishes to review how Quality Assurance (QA) issues could be treated in future work both in undertaking their own Performance Assessment (PA) calculations and in scrutinising documents supplied by SKB (on planning a repository for spent fuels in Sweden). The aim of this report is to identify the key QA issues and to outline the nature and content of a QA plan which would be suitable for SKI, bearing in mind the requirements and recommendations of relevant standards. Emphasis is on issues which are specific to Performance Assessments for deep repositories for radioactive wastes, but consideration is also given to issues which need to be addressed in all large projects. Given the long time over which the performance of a deep repository system must be evaluated, the demonstration that a repository is likely to perform satisfactorily relies on the use of computer-generated model predictions of system performance. This raises particular QA issues which are generally not encountered in other technical areas (for instance, power station operations). The traceability of the arguments used is a key QA issue, as are conceptual model uncertainty, and code verification and validation; these were all included in the consideration of overall uncertainties in the Site-94 project. Additionally, issues which are particularly relevant to SKI include: How QA in a PA fits in with the general QA procedures of the organisation undertaking the work. The relationship between QA as applied by the regulator and the implementor of a repository development programme. Section 2 introduces the discussion of these issues by reviewing the standards and guidance which are available from national and international organisations. This is followed in Section 3 by a review of specific issues which arise from the Site-94 exercise. An outline procedure for managing QA issues in SKI is put forward as a basis for discussion in Section 4. It is hoped that

  14. Quality assurance in performance assessments

    Energy Technology Data Exchange (ETDEWEB)

    Maul, P.R.; Watkins, B.M.; Salter, P.; Mcleod, R [QuantiSci Ltd, Henley-on-Thames (United Kingdom)

    1999-01-01

    Following publication of the Site-94 report, SKI wishes to review how Quality Assurance (QA) issues could be treated in future work both in undertaking their own Performance Assessment (PA) calculations and in scrutinising documents supplied by SKB (on planning a repository for spent fuels in Sweden). The aim of this report is to identify the key QA issues and to outline the nature and content of a QA plan which would be suitable for SKI, bearing in mind the requirements and recommendations of relevant standards. Emphasis is on issues which are specific to Performance Assessments for deep repositories for radioactive wastes, but consideration is also given to issues which need to be addressed in all large projects. Given the long time over which the performance of a deep repository system must be evaluated, the demonstration that a repository is likely to perform satisfactorily relies on the use of computer-generated model predictions of system performance. This raises particular QA issues which are generally not encountered in other technical areas (for instance, power station operations). The traceability of the arguments used is a key QA issue, as are conceptual model uncertainty, and code verification and validation; these were all included in the consideration of overall uncertainties in the Site-94 project. Additionally, issues which are particularly relevant to SKI include: How QA in a PA fits in with the general QA procedures of the organisation undertaking the work. The relationship between QA as applied by the regulator and the implementor of a repository development programme. Section 2 introduces the discussion of these issues by reviewing the standards and guidance which are available from national and international organisations. This is followed in Section 3 by a review of specific issues which arise from the Site-94 exercise. An outline procedure for managing QA issues in SKI is put forward as a basis for discussion in Section 4. It is hoped that

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

    Science.gov (United States)

    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.

  16. Impulsivity modulates performance under response uncertainty in a reaching task.

    Science.gov (United States)

    Tzagarakis, C; Pellizzer, G; Rogers, R D

    2013-03-01

    We sought to explore the interaction of the impulsivity trait with response uncertainty. To this end, we used a reaching task (Pellizzer and Hedges in Exp Brain Res 150:276-289, 2003) where a motor response direction was cued at different levels of uncertainty (1 cue, i.e., no uncertainty, 2 cues or 3 cues). Data from 95 healthy adults (54 F, 41 M) were analysed. Impulsivity was measured using the Barratt Impulsiveness Scale version 11 (BIS-11). Behavioral variables recorded were reaction time (RT), errors of commission (referred to as 'early errors') and errors of precision. Data analysis employed generalised linear mixed models and generalised additive mixed models. For the early errors, there was an interaction of impulsivity with uncertainty and gender, with increased errors for high impulsivity in the one-cue condition for women and the three-cue condition for men. There was no effect of impulsivity on precision errors or RT. However, the analysis of the effect of RT and impulsivity on precision errors showed a different pattern for high versus low impulsives in the high uncertainty (3 cue) condition. In addition, there was a significant early error speed-accuracy trade-off for women, primarily in low uncertainty and a 'reverse' speed-accuracy trade-off for men in high uncertainty. These results extend those of past studies of impulsivity which help define it as a behavioural trait that modulates speed versus accuracy response styles depending on environmental constraints and highlight once more the importance of gender in the interplay of personality and behaviour.

  17. The cognitive complexity of concurrent cognitive-motor tasks reveals age-related deficits in motor performance

    DEFF Research Database (Denmark)

    Oliveira, Anderson Souza; Reiche, Mikkel Staall; Vinescu, Cristina Ioana

    2018-01-01

    Aging reduces cognitive functions, and such impairments have implications in mental and motor performance. Cognitive function has been recently linked to the risk of falls in older adults. Physical activities have been used to attenuate the declines in cognitive functions and reduce fall incidence......, but little is known whether a physically active lifestyle can maintain physical performance under cognitively demanding conditions. The aim of this study was to verify whether physically active older adults present similar performance deficits during upper limb response time and precision stepping walking...... tasks when compared to younger adults. Both upper limb and walking tasks involved simple and complex cognitive demands through decision-making. For both tasks, decision-making was assessed by including a distracting factor to the execution. The results showed that older adults were substantially slower...

  18. 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

  19. The developmental dynamics of task-avoidant behavior and math performance in kindergarten and elementary school

    OpenAIRE

    Hirvonen, Riikka; Tolvanen, Asko; Aunola, Kaisa; Nurmi, Jari-Erik

    2012-01-01

    Besides cognitive factors, children's learning at school may be influenced by more dynamic phenomena, such as motivation and achievement-related task-avoidant behavior. The present study examined the developmental dynamics of task-avoidant behavior and math performance from kindergarten to Grade 4. A total of 225 children were tested for their arithmetic skills in kindergarten and in Grades 1, 2, and 4 of elementary school. Children's task-avoidant behavior in learning situations was rated by...

  20. Communicating Performance Assessments Results - 13609

    International Nuclear Information System (INIS)

    Layton, Mark

    2013-01-01

    The F-Area Tank Farms (FTF) and H-Area Tank Farm (HTF) are owned by the U.S. Department of Energy (DOE) and operated by Savannah River Remediation LLC (SRR), Liquid Waste Operations contractor at DOE's Savannah River Site (SRS). The FTF and HTF are active radioactive waste storage and treatment facilities consisting of 51 carbon steel waste tanks and ancillary equipment such as transfer lines, evaporators and pump tanks. Performance Assessments (PAs) for each Tank Farm have been prepared to support the eventual closure of the underground radioactive waste tanks and ancillary equipment. PAs provide the technical bases and results to be used in subsequent documents to demonstrate compliance with the pertinent requirements for final closure of the Tank Farms. The Tank Farms are subject to a number of regulatory requirements. The State regulates Tank Farm operations through an industrial waste water permit and through a Federal Facility Agreement approved by the State, DOE and the Environmental Protection Agency (EPA). Closure documentation will include State-approved Tank Farm Closure Plans and tank-specific closure modules utilizing information from the PAs. For this reason, the State of South Carolina and the EPA must be involved in the performance assessment review process. The residual material remaining after tank cleaning is also subject to reclassification prior to closure via a waste determination pursuant to Section 3116 of the Ronald W. Reagan National Defense Authorization Act of Fiscal Year 2005. PAs are performance-based, risk-informed analyses of the fate and transport of FTF and HTF residual wastes following final closure of the Tank Farms. Since the PAs serve as the primary risk assessment tools in evaluating readiness for closure, it is vital that PA conclusions be communicated effectively. In the course of developing the FTF and HTF PAs, several lessons learned have emerged regarding communicating PA results. When communicating PA results it is

  1. Evaluation of workers' perceived sense of slip and effect of prior knowledge of slipperiness during task performance on slippery surfaces.

    Science.gov (United States)

    Chiou, S; Bhattacharya, A; Succop, P A

    2000-01-01

    Forty healthy industrial workers (age: 41.0+/-14.9 years) were tested for postural stability for three simulated tasks: (1) standing upright; (2) rapid trunk movement; and (3) lateral reach during lifting. These tasks were performed on four levels of slippery surfaces under different environmental lighting with new or workers' own old shoes. Prior to postural stability tests, each subject was given the opportunity to assess the surface slipperiness that he or she would encounter in the subsequent postural stability tests. A perceived sense of slip (PSOS) scale was administrated immediately after each test to determine subjects' PSOS. Subjects' postural sway and instability during task performance was determined by using a strain gauge type force platform. Results from this study indicate that subjects who were cautious in assessing surface slipperiness had less postural instability during task performance. Subjects could perceive the likely slips due to the change in task (p=0.0001) and surface slipperiness (p=0.0001). The PSOS scale is reproducible, easy to use, and provides a simple way to evaluate potential slip hazards in the workplace. Results from this study should aid understanding of the factors critical to maintaining postural stability on slippery surfaces, and will help to develop guidelines for safety training and identify slip hazards in the workplace.

  2. 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.

  3. 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.

  4. Structural Design of HRA Database using generic task for Quantitative Analysis of Human Performance

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Hwan; Kim, Yo Chan; Choi, Sun Yeong; Park, Jin Kyun; Jung Won Dea [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    This paper describes a design of generic task based HRA database for quantitative analysis of human performance in order to estimate the number of task conductions. The estimation method to get the total task conduction number using direct counting is not easy to realize and maintain its data collection framework. To resolve this problem, this paper suggests an indirect method and a database structure using generic task that enables to estimate the total number of conduction based on instructions of operating procedures of nucle