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Sample records for surgical task performance

  1. Emotional intelligence and stress in medical students performing surgical tasks.

    Science.gov (United States)

    Arora, Sonal; Russ, Stephanie; Petrides, K V; Sirimanna, Pramudith; Aggarwal, Rajesh; Darzi, Ara; Sevdalis, Nick

    2011-10-01

    Poor stress management skills can compromise performance in the operating room, particularly in inexperienced trainees. Little is known about individual differences in managing stress. This study aimed to explore the relationship between trait emotional intelligence (EI) and objective and subjective measures of stress in medical students faced with unfamiliar surgical tasks. Seventeen medical undergraduates completed an unfamiliar laparoscopic task on a simulator during January to April 2008. Subjective stress before, during (retrospectively), and after the task was measured using the self-report State-Trait Anxiety Inventory. Objective stress was measured using continuous heart rate (HR) monitoring. Participants also completed the Trait Emotional Intelligence Questionnaire short form (TEIQue-SF). The authors computed scores for global trait EI and the TEIQue-SF four factors and carried out descriptive and correlational analyses. The highest levels of subjective stress were reported during the task and correlated positively with trait EI as well as with the trait EI factors of well-being and emotionality. Objective stress (mean HR) during the task was positively related to the sociability factor of trait EI. Higher trait EI scores were also associated with better after-task recovery from stress experienced during the task. Students with higher trait EI are more likely to experience stress during unfamiliar surgical scenarios but are also more likely to recover better compared with their lower-trait-EI peers. Trait EI has implications for the design of effective stress management training tailored to individual needs and potential applications to surgical trainee selection and development.

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

    Science.gov (United States)

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

    2010-04-01

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

  3. The Mozart effect on task performance in a laparoscopic surgical simulator.

    Science.gov (United States)

    Wiseman, Michael C

    2013-10-01

    The Mozart Effect is a phenomenon whereby certain pieces of music induce temporary enhancement in "spatial temporal reasoning." To determine whether the Mozart Effect can improve surgical performance, 55 male volunteers (mean age = 20.6 years, range = 16-27), novice to surgery, were timed as they completed an activity course on a laparoscopic simulator. Subjects were then randomized for exposure to 1 of 2 musical pieces by Mozart (n = 21) and Dream Theater (n = 19), after which they repeated the course. Following a 15-minute exposure to a nonmusical piece, subjects were exposed to one of the pieces and performed the activity course a third time. An additional group (n = 15) that was not corandomized performed the tasks without any exposure to music. The percent improvements in completion time between 3 successive trials were calculated for each subject and group means compared. In 2 of the tasks, subjects exposed to the Dream Theater piece achieved approximately 30% more improvement (26.7 ± 8.3%) than those exposed to the Mozart piece (20.2 ± 7.8%, P = .021) or to no music (20.4 ± 9.1%, P = .049). Distinct patterns of covariance between baseline performance and subsequent improvement were observed for the different musical conditions and tasks. The data confirm the existence of a Mozart Effect and demonstrate for the first time its practical applicability. Prior exposure to certain pieces may enhance performance in practical skills requiring spatial temporal reasoning.

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

    NARCIS (Netherlands)

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

    2009-01-01

    Background. Surgeons perform complex tasks while exposed to multiple distracting sources that may increase stress in the operating room (e.g., music, conversation, and unadapted use of sophisticated technologies). This study aimed to examine whether such realistic social and technological distractin

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

    NARCIS (Netherlands)

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

    2009-01-01

    Background. Surgeons perform complex tasks while exposed to multiple distracting sources that may increase stress in the operating room (e.g., music, conversation, and unadapted use of sophisticated technologies). This study aimed to examine whether such realistic social and technological

  6. Performance of language tasks in patients with ruptured aneurysm of the left hemisphere worses in the post-surgical evaluation

    Directory of Open Access Journals (Sweden)

    Ana Cláudia C. Vieira

    2016-08-01

    Full Text Available ABSTRACT Sub-arachnoid hemorrhage (SAH promotes impairment of upper cortical functions. However, few information is available emphasizing changes in language after aneurismal SAH and aneurysm location influence. Objective To assess the language and verbal fluency performance in aneurismal SAH pre- and post-surgery in patients caused by an aneurysm of the anterior communicating artery (AcomA, left middle cerebral artery (L-MCA and left posterior comunicating artery (L-PcomA. Methods Assessment in 79 patients with SAH, on two occasions: pre- and post surgical treatment. They were divided into three groups by the aneurysms’ location. Results Deterioration is detected in the performance of all patients during the post-surgical period; L-MCA aneurysm patients displayed a reduction in verbal naming and fluency; L-PcomA patients deteriorated in the written language and fluency tasks. Conclusion After the surgical procedure the patients decreased in various language tasks and these differences in performance being directly related to the location of the aneurysm.

  7. Development of a Cognitive Robotic System for Simple Surgical Tasks

    Directory of Open Access Journals (Sweden)

    Riccardo Muradore

    2015-04-01

    Full Text Available The introduction of robotic surgery within the operating rooms has significantly improved the quality of many surgical procedures. Recently, the research on medical robotic systems focused on increasing the level of autonomy in order to give them the possibility to carry out simple surgical actions autonomously. This paper reports on the development of technologies for introducing automation within the surgical workflow. The results have been obtained during the ongoing FP7 European funded project Intelligent Surgical Robotics (I-SUR. The main goal of the project is to demonstrate that autonomous robotic surgical systems can carry out simple surgical tasks effectively and without major intervention by surgeons. To fulfil this goal, we have developed innovative solutions (both in terms of technologies and algorithms for the following aspects: fabrication of soft organ models starting from CT images, surgical planning and execution of movement of robot arms in contact with a deformable environment, designing a surgical interface minimizing the cognitive load of the surgeon supervising the actions, intra-operative sensing and reasoning to detect normal transitions and unexpected events. All these technologies have been integrated using a component-based software architecture to control a novel robot designed to perform the surgical actions under study. In this work we provide an overview of our system and report on preliminary results of the automatic execution of needle insertion for the cryoablation of kidney tumours.

  8. Development of a Cognitive Robotic System for Simple Surgical Tasks

    Directory of Open Access Journals (Sweden)

    Riccardo Muradore

    2015-04-01

    Full Text Available The introduction of robotic surgery within the operating rooms has significantly improved the quality of many surgical procedures. Recently, the research on medical robotic systems focused on increasing the level of autonomy in order to give them the possibility to carry out simple surgical actions autonomously. This paper reports on the development of technologies for introducing automation within the surgical workflow. The results have been obtained during the ongoing FP7 European funded project Intelligent Surgical Robotics (I-SUR. The main goal of the project is to demonstrate that autonomous robotic surgical systems can carry out simple surgical tasks effectively and without major intervention by surgeons. To fulfil this goal, we have developed innovative solutions (both in terms of technologies and algorithms for the following aspects: fabrication of soft organ models starting from CT images, surgical planning and execution of movement of robot arms in contact with a deformable environment, designing a surgical interface minimizing the cognitive load of the surgeon supervising the actions, intra-operative sensing and reasoning to detect normal transitions and unexpected events. All these technologies have been integrated using a component-based software architecture to control a novel robot designed to perform the surgical actions under study. In this work we provide an overview of our system and report on preliminary results of the automatic execution of needle insertion for the cryoablation of kidney tumours.

  9. Board Task Performance

    DEFF Research Database (Denmark)

    Minichilli, Alessandro; Zattoni, Alessandro; Nielsen, Sabina

    2012-01-01

    This paper addresses recent calls to narrow the micro–macro gap in management research (Bamberger, 2008), by incorporating a macro-level context variable (country) in exploring micro-level determinants of board effectiveness. Following the integrated model proposed by Forbes and Milliken (1999), we...... 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...... influence board tasks, and how the context moderates the relationship between processes and tasks. Our hypotheses are tested on a survey-based dataset of 535 medium-sized and large industrial firms in Italy and Norway, which are considered to substantially differ along legal and cultural dimensions...

  10. Providing surgical care in Somalia: A model of task shifting

    Directory of Open Access Journals (Sweden)

    Ford Nathan P

    2011-07-01

    Full Text Available Abstract Background Somalia is one of the most political unstable countries in the world. Ongoing insecurity has forced an inconsistent medical response by the international community, with little data collection. This paper describes the "remote" model of surgical care by Medecins Sans Frontieres, in Guri-El, Somalia. The challenges of providing the necessary prerequisites for safe surgery are discussed as well as the successes and limitations of task shifting in this resource-limited context. Methods In January 2006, MSF opened a project in Guri-El located between Mogadishu and Galcayo. The objectives were to reduce mortality due to complications of pregnancy and childbirth and from violent and non-violent trauma. At the start of the program, expatriate surgeons and anesthesiologists established safe surgical practices and performed surgical procedures. After January 2008, expatriates were evacuated due to insecurity and surgical care has been provided by local Somalian doctors and nurses with periodic supervisory visits from expatriate staff. Results Between October 2006 and December 2009, 2086 operations were performed on 1602 patients. The majority (1049, 65% were male and the median age was 22 (interquartile range, 17-30. 1460 (70% of interventions were emergent. Trauma accounted for 76% (1585 of all surgical pathology; gunshot wounds accounted for 89% (584 of violent injuries. Operative mortality (0.5% of all surgical interventions was not higher when Somalian staff provided care compared to when expatriate surgeons and anesthesiologists. Conclusions The delivery of surgical care in any conflict-settings is difficult, but in situations where international support is limited, the challenges are more extreme. In this model, task shifting, or the provision of services by less trained cadres, was utilized and peri-operative mortality remained low demonstrating that safe surgical practices can be accomplished even without the presence of fully

  11. Performing Task Integration

    DEFF Research Database (Denmark)

    Elkjaer, Bente; Nickelsen, Niels Christian Mossfeldt

    . 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......In the paper, we deal with how to organize work for cross-professional knowledge sharing. We do so inspired by relational coordination theory, which is affiliated with positive organizational scholarship. Relational coordination theory is constituted by a combination of relationships marked...... away with differences regarding task definitions and working conditions as well as professional knowledge hierarchies and responsibilities for parts and wholes....

  12. 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 individua...

  13. Development of a Cognitive Robotic System for Simple Surgical Tasks

    OpenAIRE

    Riccardo Muradore; Paolo Fiorini; Gokhan Akgun; Duygun Erol Barkana; Marcello Bonfe; Fabrizio Boriero; Andrea Caprara; Giacomo Rossi; Riccardo Dodi; Ole Jakob Elle; Federica Ferraguti; Lorenza Gasperotti; Roger Gassert; Kim Mathiassen; Dilla Handini

    2015-01-01

    ARTICLE International Journal of Advanced Robotic Systems Development of a Cognitive Robotic System for Simple Surgical Tasks Invited Feature Article Riccardo Muradore1*, Paolo Fiorini1, Gokhan Akgun2, Duygun Erol Barkana3, Marcello Bonfe4, Fabrizio Boriero1, Andrea Caprara11, Giacomo De Rossi1, Riccardo Dodi5, Ole Jakob Elle6, Federica Ferraguti7, Lorenza Gasperotti1, Roger Gassert8, Kim Mathiassen6, Dilla Handini9, Olivier Lambercy8, Lin Li10, Maarja Kruusmaa10, Aura...

  14. The effect of fasting on surgical performance

    DEFF Research Database (Denmark)

    Schefte, David Fenger; Rosenstock, Steffen Jais

    2016-01-01

    BACKGROUND: It is unknown whether fasting has any impact on surgical performance. This simulator-based study investigates whether fasting affects surgical performance. METHODS: Twelve healthy medical students [seven women, mean age 26.5 years (range 23-34)] with no prior experience with surgical...... simulators underwent a short course introduction to the LapSim(®) simulator. After having reached a predefined level, the participants performed five simulated salpingectomies on the LapSim(®) simulator 5-30 days after the initial introduction. The procedures took place at 9 a.m. and 2 p.m. after fasting...... in the longitudinal axis with the left hand. CONCLUSION: The simulator-based study suggests that 17 h of fasting does not deteriorate surgical performance. Further studies on the effect of fasting on surgical performance are needed....

  15. The effect of music on robot-assisted laparoscopic surgical performance.

    Science.gov (United States)

    Siu, Ka-Chun; Suh, Irene H; Mukherjee, Mukul; Oleynikov, Dmitry; Stergiou, Nick

    2010-12-01

    Music is often played in the operating room to increase the surgeon's concentration and to mask noise. It could have a beneficial effect on surgical performance. Ten participants with limited experience with the da Vinci robotic surgical system were recruited to perform two surgical tasks: suture tying and mesh alignment when classical, jazz, hip-hop, and Jamaican music were presented. Kinematics of the instrument tips of the surgical robot and surface electromyography of the subjects were recorded. Results revealed that a significant music effect was found for both tasks with decreased time to task completion (P = .005) and total travel distance (P = .021) as well as reduced muscle activations ( P = .016) and increased median muscle frequency (P = .034). Subjects improved their performance significantly when they listened to either hip-hop or Jamaican music. In conclusion, music with high rhythmicity has a beneficial effect on robotic surgical performance. Musical environment may benefit surgical training and make acquisition of surgical skills more efficient.

  16. Pre-task music improves swimming performance.

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    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.

  17. Individual Differences in Secondary Task Performance.

    Science.gov (United States)

    1980-09-01

    task similar to that used by Atkinson and Shiffrin (1968). The spatial task in- volved holding in memory a random pattern of plus signs. In all cases...may serve to attenuate the easy-to-hard correlation. I *1,~ __ __ _ Secondary Task Performance 33 References Atkinson , R. C., & Shiffrin , R. M. Human...aIde if nec.eaar, and Identify by block number) ability, attention, dual task, information processing, individual differences memory , secondary task

  18. Evaluation of input devices for teleoperation of concentric tube continuum robots for surgical tasks

    Science.gov (United States)

    Fellmann, Carolin; Kashi, Daryoush; Burgner-Kahrs, Jessica

    2015-03-01

    For those minimally invasive surgery where conventional surgical instruments cannot reach the surgical site due to their straight structure and rigidity, concentric tube continuum robots are a promising technology because of their small size (comparable to a needle) and maneuverability. These flexible, compliant manipulators can easily access hard to reach anatomical structures, e.g. by turning around corners. By teleoperating the robot the surgeon stays in direct control at any time. In this paper, three off-the-shelf input devices are considered for teleoperation of a concentric tube continuum robot: a 3D mouse, a gamepad, and a 3 degrees of freedom haptic input device. Three tasks which mimic relevant surgical maneuvers are performed by 12 subjects using each input device: reaching specific locations, picking and placing objects from one location to another, and approaching the surgical site through a restricted pathway. We present quantitative results (task completion time, accuracy, etc.), a statistical analysis, and empirical results (questionnaires). Overall, the performance of subjects using the 3D mouse was superior to the performance using the other input devices. The subjective ranking of the 3D mouse by the subjects confirms this result.

  19. Dexterity testing and residents' surgical performance.

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    Kirby, T J

    1979-01-01

    1. With some exceptions, those who choose ophthalmology as a career may approximate the general population in innate manual dexterity. 2. Many factors other than manual dexterity influence the development of surgical skills by residents. 3. If dexterity testing is to be used, the addition or inclusion of tests for spatial aptitudes may be more helpful than simple dexterity tests alone. The predictive value of such tests for surgical performance would need vertification. 4. The development of a special test directly related to handling surgical instruments, to cutting, and to sewing (the criteria) may be more practical than the ones used in this study.

  20. Real-time segmentation and recognition of surgical tasks in cataract surgery videos.

    Science.gov (United States)

    Quellec, Gwénolé; Lamard, Mathieu; Cochener, Béatrice; Cazuguel, Guy

    2014-12-01

    In ophthalmology, it is now common practice to record every surgical procedure and to archive the resulting videos for documentation purposes. In this paper, we present a solution to automatically segment and categorize surgical tasks in real-time during the surgery, using the video recording. The goal would be to communicate information to the surgeon in due time, such as recommendations to the less experienced surgeons. The proposed solution relies on the content-based video retrieval paradigm: it reuses previously archived videos to automatically analyze the current surgery, by analogy reasoning. Each video is segmented, in real-time, into an alternating sequence of idle phases, during which no clinically-relevant motions are visible, and action phases. As soon as an idle phase is detected, the previous action phase is categorized and the next action phase is predicted. A conditional random field is used for categorization and prediction. The proposed system was applied to the automatic segmentation and categorization of cataract surgery tasks. A dataset of 186 surgeries, performed by ten different surgeons, was manually annotated: ten possibly overlapping surgical tasks were delimited in each surgery. Using the content of action phases and the duration of idle phases as sources of evidence, an average recognition performance of Az = 0.832 ± 0.070 was achieved.

  1. [Study of tasks performed by nurses in a teaching hospital].

    Science.gov (United States)

    Costa, Rita de Almeida; Shimizu, Helena Eri

    2006-09-01

    The purpose of this study was to analyze tasks performed by nurses at hospitalization units (maternity, general medicine, surgical and pediatric) in a training hospital in order to better know which factors make it difficult to outline their role as well as the meaning of their actions. It's a descriptive-type qualitative research. Twenty nurses were interviewed following a half-structured script. Nurses perceive that they perform help-providing tasks more frequently, followed by administrative tasks, dealing with the information system and educational tasks. The lack of skilled human resources, essentially nurses, infrastructure, valorization of nursing care and its workers, work organization and integration among members of the multi-disciplinary staff were identified as work-hampering factors.

  2. The minimum entropy principle and task performance.

    Science.gov (United States)

    Guastello, Stephen J; Gorin, Hillary; Huschen, Samuel; Peters, Natalie E; Fabisch, Megan; Poston, Kirsten; Weinberger, Kelsey

    2013-07-01

    According to the minimum entropy principle, efficient cognitive performance is produced with a neurocognitive strategy that involves a minimum of degrees of freedom. Although high performance is often regarded as consistent performance as well, some variability in performance still remains which allows the person to adapt to changing goal conditions or fatigue. The present study investigated the connection between performance, entropy in performance, and four task-switching strategies. Fifty-one undergraduates performed 7 different computer-based cognitive tasks producing sets of 49 responses under instructional conditions requiring task quotas or no quotas. The temporal patterns of performance were analyzed using orbital decomposition to extract pattern types and lengths, which were then compared with regard to Shannon entropy, topological entropy, and overall performance. Task switching strategies from a previous study were available for the same participants as well. Results indicated that both topological entropy and Shannon entropy were negatively correlated with performance. Some task-switching strategies produced lower entropy in performance than others. Stepwise regression showed that the top three predictors of performance were Shannon entropy and arithmetic and spatial abilities. Additional implications for the prediction of work performance with cognitive ability measurements and the applicability of the minimum entropy principle to multidimensional performance criteria and team work are discussed.

  3. 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

  4. 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

  5. Teleoperation in surgical robotics--network latency effects on surgical performance.

    Science.gov (United States)

    Lum, Mitchell J H; Rosen, Jacob; King, Hawkeye; Friedman, Diana C W; Lendvay, Thomas S; Wright, Andrew S; Sinanan, Mika N; Hannaford, Blake

    2009-01-01

    A teleoperated surgical robotic system allows surgical procedures to be conducted across long distances while utilizing wired and wireless communication with a wide spectrum of performance that may affect the outcome. An open architecture portable surgical robotic system (Raven) was developed for both open and minimally invasive surgery. The system has been the subject of an intensive telesurgical experimental protocol aimed at exploring the boundaries of the system and surgeon performance during a series of field experiments in extreme environments (desert and underwater) teleportation between US, Europe, and Japan as well as lab experiments under synthetic fixed time delay. One standard task (block transfer emulating tissue manipulation) of the Fundamentals of Laparoscopic Surgery (FLS) training kit was used for the experimental protocol. Network characterization indicated a typical time delay in the range of 16-172 ms in field experiments. The results of the lab experiments showed that the completion time of the task as well as the length of the tool tip trajectory significantly increased (alphaerrors (block drooping) as well as the completion time and the tool tip path length at different time delays.

  6. Mobile task management tool that improves workflow of an acute general surgical service.

    Science.gov (United States)

    Foo, Elizabeth; McDonald, Rod; Savage, Earle; Floyd, Richard; Butler, Anthony; Rumball-Smith, Alistair; Connor, Saxon

    2015-10-01

    Understanding and being able to measure constraints within a health system is crucial if outcomes are to be improved. Current systems lack the ability to capture decision making with regard to tasks performed within a patient journey. The aim of this study was to assess the impact of a mobile task management tool on clinical workflow within an acute general surgical service by analysing data capture and usability of the application tool. The Cortex iOS application was developed to digitize patient flow and provide real-time visibility over clinical decision making and task performance. Study outcomes measured were workflow data capture for patient and staff events. Usability was assessed using an electronic survey. There were 449 unique patient journeys tracked with a total of 3072 patient events recorded. The results repository was accessed 7792 times. The participants reported that the application sped up decision making, reduced redundancy of work and improved team communication. The mode of the estimated time the application saved participants was 5-9 min/h of work. Of the 14 respondents, nine discarded their analogue methods of tracking tasks by the end of the study period. The introduction of a mobile task management system improved the working efficiency of junior clinical staff. The application allowed capture of data not previously available to hospital systems. In the future, such data will contribute to the accurate mapping of patient journeys through the health system. © 2015 Royal Australasian College of Surgeons.

  7. 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.

  8. 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 br

  9. 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…

  10. [Tasks performed by nurses at inpatient units in a training hospital].

    Science.gov (United States)

    Costa, Rita de Almeida; Shimizu, Helena Eri

    2005-01-01

    The purpose of this study was to identify and analyze tasks performed by nurses at inpatient units in a large general hospital in Brasilia, Federal District, which also functions as a training hospital. A quantitative, exploratory, descriptive study was carried out and involved a total of 612 hours of direct observation of the activities performed by 18 nurses at the General Medicine, Surgical, Pediatric and Maternity units. The tasks observed were classified as: administration, nursing care delivery, education and related to information system. Nurses dedicate a large part of their time to administrative tasks, followed by tasks related to nursing care delivery and information system, performing almost no educative tasks.

  11. Mechanical performance of gamma irradiated surgical sutures

    Energy Technology Data Exchange (ETDEWEB)

    Pino, Eddy S.; Rela, Paulo P. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2000-07-01

    Surgical sutures are medical devices made of natural or synthetic polymeric materials that, due to its end-use, have to be sterilized. Historically, the sterilization by heat or using ethylene oxide had presented so numerous drawbacks that today the non-pollutant radiation sterilization has become a well established sterilization process, that brings, environmental, technical, and economical advantages. The amount of irradiation doses required for sterilization of health care products is 25 kGy in most instances to achieve the necessary sterility assurance level. As high energy radiation produces modifications in the molecular structure of organic materials with changes in its mechanical properties, the aim of this work was to evaluate the mechanical behavior of surgical sutures under irradiation. Silk, polyamide and catgut sutures were gamma irradiated up to doses of 50 kGy in an industrial irradiation sterilization plant. Afterwards, these sutures were mechanical tested for tensile strength under knot following the specifications of the NBR13904 draft standard, using the CTRD-INSTRON at IPEN. The mechanical lab results show that sutures made of Silk and Polyamide do not present any change in their mechanical performance up to the dose of 50 kGy. On the other hand, Catgut present mechanical stability up to 30 kGy and afterwards, a slight decrease in its tensile strength was detected. (author)

  12. A quality improvement study on avoidable stressors and countermeasures affecting surgical motor performance and learning.

    Science.gov (United States)

    Conrad, Claudius; Konuk, Yusuf; Werner, Paul D; Cao, Caroline G; Warshaw, Andrew L; Rattner, David W; Stangenberg, Lars; Ott, Harald C; Jones, Daniel B; Miller, Diane L; Gee, Denise W

    2012-06-01

    To explore how the 2 most important components of surgical performance--speed and accuracy-are influenced by different forms of stress and what the impact of music is on these factors. On the basis of a recently published pilot study on surgical experts, we designed an experiment examining the effects of auditory stress, mental stress, and music on surgical performance and learning and then correlated the data psychometric measures to the role of music in a novice surgeon's life. Thirty-one surgeons were recruited for a crossover study. Surgeons were randomized to 4 simple standardized tasks to be performed on the SurgicalSIM VR laparoscopic simulator (Medical Education Technologies, Inc, Sarasota, FL), allowing exact tracking of speed and accuracy. Tasks were performed under a variety of conditions, including silence, dichotic music (auditory stress), defined classical music (auditory relaxation), and mental loading (mental arithmetic tasks). Tasks were performed twice to test for memory consolidation and to accommodate for baseline variability. Performance was correlated to the brief Musical Experience Questionnaire (MEQ). Mental loading influences performance with respect to accuracy, speed, and recall more negatively than does auditory stress. Defined classical music might lead to minimally worse performance initially but leads to significantly improved memory consolidation. Furthermore, psychologic testing of the volunteers suggests that surgeons with greater musical commitment, measured by the MEQ, perform worse under the mental loading condition. Mental distraction and auditory stress negatively affect specific components of surgical learning and performance. If used appropriately, classical music may positively affect surgical memory consolidation. It also may be possible to predict surgeons' performance and learning under stress through psychological tests on the role of music in a surgeon's life. Further investigation is necessary to determine the

  13. Effects of a no-go Task 2 on Task 1 performance in dual - tasking: From benefits to costs.

    Science.gov (United States)

    Janczyk, Markus; Huestegge, Lynn

    2017-04-01

    When two tasks are combined in a dual-task experiment, characteristics of Task 2 can influence Task 1 performance, a phenomenon termed the backward crosstalk effect (BCE). Besides instances depending on the (spatial) compatibility of both responses, a particularly interesting example was introduced by Miller (2006): If Task 2 was a no-go task (i.e., one not requiring any action at all), responses were slowed in Task 1. Subsequent work, however, also reported the opposite result-that is, faster Task 1 responses in cases of no-go Task 2 trials. We report three experiments aiming to more precisely identify the conditions under which a no-go Task 2 facilitates or impedes Task 1 performance. The results suggest that an adverse no-go BCE is only observed when the Task 2 response(s) are sufficiently prepared in advance, yielding strong inhibitory control demands for Task 2 that eventually hamper Task 1 processing as well (i.e., inhibitory costs). If this is not the case, encountering a no-go Task 2 trial facilitates Task 1 performance, suggesting that the underlying task representation is reduced to a single - task. These results are discussed in the context of other recent work on BCEs and of recently suggested accounts of the no-go BCE.

  14. Investigating Effects of Task Structure on EFL Learner's Oral Performance

    Science.gov (United States)

    Rahimpour, Massoud; Mehrang, Faezeh

    2010-01-01

    It is argued that tasks with different structures yield different performances in terms of accuracy, fluency and complexity. The present study is thus an attempt to investigate the impact of task structure on second language task performance. Thirty two upper-intermediate Iranian learners of English performed two narrative tasks (Structured vs.…

  15. Emotional priming effects during Stroop task performance.

    Science.gov (United States)

    Hart, Sarah J; Green, Steven R; Casp, Michael; Belger, Aysenil

    2010-02-01

    The ability to make decisions within an emotional context requires a balance between two functionally integrated neural systems that primarily support executive control and affective processing. Several studies have demonstrated effects of emotional interference presented during an ongoing cognitive task, but it is unclear how activating the emotional circuitry prior to a cognitive task may enhance or disrupt the executive system. In this study we used fMRI to examine the effects of emotional priming on executive processing during a number Stroop task. Our results indicated that during trials with less executive requirements, there was a greater aversive emotional attenuation effect in a network of regions including the ventrolateral prefrontal cortex (vlPFC), insula and cingulate gyrus. This attenuation effect was counteracted during trials with increased executive demand, suggesting that while pre-activation of the emotional system may lead to an automatic attenuation of activity in multiple regions, requirements for executive function may override the aversive emotional attenuation effect. Furthermore, this override effect was found to be associated with faster reaction times during executive processing. These findings demonstrate that activity in the vlPFC, cingulate and insula is dynamically adjusted in order to optimize performance, and illustrate the importance of the timing of each system's engagement in determining how competing cognitive and emotional information is processed.

  16. Musical expertise has minimal impact on dual task performance

    OpenAIRE

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

    2017-01-01

    Studies investigating effect of practice on dual task performance have yielded conflicting findings, thus supporting different theoretical accounts about the organization 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. \\ud \\ud Our study compared...

  17. The harder the task, the more inconsistent the performance: a PPT analysis on task difficulty.

    Science.gov (United States)

    Rice, Stephen; Geels, Kasha; Hackett, Holly Raye; Trafimow, David; McCarley, Jason S; Schwark, Jeremy; Hunt, Gayle

    2012-01-01

    Previous research has demonstrated that as task difficulty increases, task performance subsequently decreases. These decrements in task performance as difficulty increases have been attributed to the processes individuals use to complete tasks. Over a series of three experiments, Potential Performance Theory (PPT; Trafimow & Rice, 2008 ; 2009), was used to test the hypothesis that decreases in task performance are, in part, due to inconsistency rather than only systematic factors. Task difficulty was manipulated in three visual search tasks by increasing set size (Experiment 1), decreasing contrast (Experiment 2), and increasing background distracters (Experiment 3). Findings over the three studies indicated that decreases in observed task performance as task difficulty increases are primarily due to a decrease of consistency rather than systematic factors. The theoretical implications of these findings are discussed.

  18. Children's construction task performance and spatial ability: controlling task complexity and predicting mathematics performance.

    Science.gov (United States)

    Richardson, Miles; Hunt, Thomas E; Richardson, Cassandra

    2014-12-01

    This paper presents a methodology to control construction task complexity and examined the relationships between construction performance and spatial and mathematical abilities in children. The study included three groups of children (N = 96); ages 7-8, 10-11, and 13-14 years. Each group constructed seven pre-specified objects. The study replicated and extended previous findings that indicated that the extent of component symmetry and variety, and the number of components for each object and available for selection, significantly predicted construction task difficulty. Results showed that this methodology is a valid and reliable technique for assessing and predicting construction play task difficulty. Furthermore, construction play performance predicted mathematical attainment independently of spatial ability.

  19. 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.

  20. The assessment and management of older cancer patients : A SIOG surgical task force survey on surgeons' attitudes

    NARCIS (Netherlands)

    Ghignone, F; van Leeuwen, B. L.; Montroni, I; Huisman, M G; Somasundar, P; Cheung, K L; Audisio, R A; Ugolini, G

    Aim: The Surgical Task Force at SIOG (International Society of Geriatric Oncology) designed this survey to explore the surgical oncologists' approach toward elderly cancer patients. Methods: A web-based survey was sent to all members of ESSO (European Society of Surgical Oncology) and SSO (Society

  1. 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

  2. Performance assessment task team progress report

    Energy Technology Data Exchange (ETDEWEB)

    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. [and others

    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 Management{close_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.

  3. 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.

  4. Cohesiveness and Performance on an Additive Task: Evidence for Multidimensionality.

    Science.gov (United States)

    Zaccaro, Stephen J.; Lowe, Charles A.

    1988-01-01

    Presents a study designed to contrast the effects of task-based and interpersonal cohesiveness on group performance of students. Concludes that high task cohesion helped group performance, while interpersonal attraction had no apparent effect. Finding that increased interpersonal cohesion improved task commitment, the authors suggest that…

  5. Aging and Concurrent Task Performance: Cognitive Demand and Motor Control

    Science.gov (United States)

    Albinet, Cedric; Tomporowski, Phillip D.; Beasman, Kathryn

    2006-01-01

    A motor task that requires fine control of upper limb movements and a cognitive task that requires executive processing--first performing them separately and then concurrently--was performed by 18 young and 18 older adults. The motor task required participants to tap alternatively on two targets, the sizes of which varied systematically. The…

  6. Physicists' Information Tasks: Structure, Length and Retrieval Performance

    DEFF Research Database (Denmark)

    Lykke, Marianne; Ingwersen, Peter; Bogers, Toine;

    2010-01-01

    to describe the tasks, 3) what semantic categories were used to express the search facets, and 4) retrieval performance. Results show variety in structure and length across task descriptions and task purposes. The results indicate effect of length and, in particular, of task purpose on retrieval performance......In this poster, we describe central aspects of 65 natural information tasks from 23 senior researchers, PhDs, and experienced MSc students from three different university departments of physics. We analyze 1) the main purpose of the information task, 2) which and how many search facets were used...

  7. Physicists' Information Tasks: Structure, Length and Retrieval Performance

    DEFF Research Database (Denmark)

    Lykke, Marianne; Ingwersen, Peter; Bogers, Toine

    2010-01-01

    to describe the tasks, 3) what semantic categories were used to express the search facets, and 4) retrieval performance. Results show variety in structure and length across task descriptions and task purposes. The results indicate effect of length and, in particular, of task purpose on retrieval performance......In this poster, we describe central aspects of 65 natural information tasks from 23 senior researchers, PhDs, and experienced MSc students from three different university departments of physics. We analyze 1) the main purpose of the information task, 2) which and how many search facets were used...

  8. 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…

  9. Lucid dreaming and ventromedial versus dorsolateral prefrontal task performance.

    Science.gov (United States)

    Neider, Michelle; Pace-Schott, Edward F; Forselius, Erica; Pittman, Brian; Morgan, Peter T

    2011-06-01

    Activity in the prefrontal cortex may distinguish the meta-awareness experienced during lucid dreams from its absence in normal dreams. To examine a possible relationship between dream lucidity and prefrontal task performance, we carried out a prospective study in 28 high school students. Participants performed the Wisconsin Card Sort and Iowa Gambling tasks, then for 1 week kept dream journals and reported sleep quality and lucidity-related dream characteristics. Participants who exhibited a greater degree of lucidity performed significantly better on the task that engages the ventromedial prefrontal cortex (the Iowa Gambling Task), but degree of lucidity achieved did not distinguish performance on the task that engages the dorsolateral prefrontal cortex (the Wisconsin Card Sort Task), nor did it distinguish self-reported sleep quality or baseline characteristics. The association between performance on the Iowa Gambling Task and lucidity suggests a connection between lucid dreaming and ventromedial prefrontal function. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Cognitive Correlates of Hemispheric Performance on Dichotic Tasks.

    Science.gov (United States)

    Johnson, Ronald C.; And Others

    1984-01-01

    Examined the relationship between performance on left and right hemisphere dominant measures of cognition and performance on dichotic memory tasks in 53 adults age 50 and older. Right hemisphere performance on dichotic and cognitive tasks showed a negative association with age while left hemisphere performance showed no decline. (JAC)

  11. Instituting a Surgical Skills Competition Increases Technical Performance of Surgical Clerkship Students Over Time.

    Science.gov (United States)

    Leraas, Harold J; Cox, Morgan L; Bendersky, Victoria A; Sprinkle, Shanna S; Gilmore, Brian F; Gunasingha, Rathnayaka M; Tracy, Elisabeth T; Sudan, Ranjan

    2017-10-04

    Surgical skills training varies greatly between institutions and is often left to students to approach independently. Although many studies have examined single interventions of skills training, no data currently exists about the implementation of surgical skills assessment as a component of the medical student surgical curriculum. We created a technical skills competition and evaluated its effect on student surgical skill development. Second-year medical students enrolled in the surgery clerkship voluntarily participated in a surgical skills competition consisting of knot tying, laparoscopic peg transfer, and laparoscopic pattern cut. Winning students were awarded dinner with the chair of surgery and a resident of their choice. Individual event times and combined times were recorded and compared for students who completed without disqualification. Disqualification included compromising cutting pattern, dropping a peg out of the field of vision, and incorrect knot tying technique. Timed performance was compared for 2 subsequent academic years using Mann-Whitney U test. Overall, 175 students competed and 71 students met qualification criteria. When compared by academic year, 2015 to 2016 students (n = 34) performed better than 2014 to 2015 students (n = 37) in pattern cut (133s vs 167s, p = 0.040), peg transfer (66s vs 101s, p skills competition improves student technical performance. Further research is needed regarding long-term benefits of surgical competitions for medical students. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  12. Human Performance in Time-Shared Verbal and Tracking Tasks.

    Science.gov (United States)

    1979-04-01

    performance of both a one-dimensional compensatory tracking task and a continuous absoluzte difference digit- proceseing task. As mentioned above, the... parts : 1) What combination of input and output (I/O) channels for the discrete information processing task provides optimum information transmission

  13. 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…

  14. Performance improvement initiative: prevention of surgical site infection (SSI).

    Science.gov (United States)

    Ng, Wai Khuan; Awad, Nawal

    2015-01-01

    Mafraq Hospital performs an average of 10,000 surgeries every year. The impact of having high volume high risk surgical procedures calls for the need to ensure safe surgery and a prevention of surgical site infection (SSI). SSI represents a significant portion of healthcare-associated infections (HAIs). The impact on morbidity, mortality, and cost of care has resulted in identifying the need to reduce SSI as a top priority to prevent healthcare associated infections. The good news is that the majority of SSIs are preventable. Mafraq Hospital performs a range of surgical procedures that covers 14 surgical specialties. The infection prevention and control team performs surveillance for SSI for all patients who undergo operative procedure included in Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) Operative Procedure Category (40 surgical procedures). Out of the 40 CDC NHSN listed, 33 operative procedures were performed at Mafraq Hospital, of which 17 were reported with SSI for 2013 and 2014. Surgical site infection has implicated an increase average length of stay from seven to 10 additional postoperative hospital days and additional costs of AED 10,000 to AED 100,000/SSI depending on procedure and pathogen. A multidisciplinary team was formed to develop and implement measures to reduce/eliminate surgical site infection, as well as evaluate and monitor compliance. Hence a group of multidisciplinary teams were initiated to analyse the results, find out the gaps, and implement a quality improvement project to correct the deficits. Recommendations for appropriate improvement measures were formed on evidence-based international guidelines from the Institute for Healthcare Improvement (IHI) and CDC. Evidence based practice supports that many of the causes of surgical site infection can be prevented with proper medical attention and care.

  15. How important tasks are performed: peer review

    CERN Document Server

    Hartonen, T; 10.1038/srep01679

    2013-01-01

    The advancement of various fields of science depends on the actions of individual scientists via the peer review process. The referees' work patterns and stochastic nature of decision making both relate to the particular features of refereeing and to the universal aspects of human behavior. Here, we show that the time a referee takes to write a report on a scientific manuscript depends on the final verdict. The data is compared to a model, where the review takes place in an ongoing competition of completing an important composite task with a large number of concurrent ones - a Deadline -effect. In peer review human decision making and task completion combine both long-range predictability and stochastic variation due to a large degree of ever-changing external "friction".

  16. How important tasks are performed: peer review

    Science.gov (United States)

    Hartonen, T.; Alava, M. J.

    2013-04-01

    The advancement of various fields of science depends on the actions of individual scientists via the peer review process. The referees' work patterns and stochastic nature of decision making both relate to the particular features of refereeing and to the universal aspects of human behavior. Here, we show that the time a referee takes to write a report on a scientific manuscript depends on the final verdict. The data is compared to a model, where the review takes place in an ongoing competition of completing an important composite task with a large number of concurrent ones - a Deadline -effect. In peer review human decision making and task completion combine both long-range predictability and stochastic variation due to a large degree of ever-changing external ``friction''.

  17. Characterization of task-free and task-performance brain states via functional connectome patterns.

    Science.gov (United States)

    Zhang, Xin; Guo, Lei; Li, Xiang; Zhang, Tuo; Zhu, Dajiang; Li, Kaiming; Chen, Hanbo; Lv, Jinglei; Jin, Changfeng; Zhao, Qun; Li, Lingjiang; Liu, Tianming

    2013-12-01

    Both resting state fMRI (R-fMRI) and task-based fMRI (T-fMRI) have been widely used to study the functional activities of the human brain during task-free and task-performance periods, respectively. However, due to the difficulty in strictly controlling the participating subject's mental status and their cognitive behaviors during R-fMRI/T-fMRI scans, it has been challenging to ascertain whether or not an R-fMRI/T-fMRI scan truly reflects the participant's functional brain states during task-free/task-performance periods. This paper presents a novel computational approach to characterizing and differentiating the brain's functional status into task-free or task-performance states, by which the functional brain activities can be effectively understood and differentiated. Briefly, the brain's functional state is represented by a whole-brain quasi-stable connectome pattern (WQCP) of R-fMRI or T-fMRI data based on 358 consistent cortical landmarks across individuals, and then an effective sparse representation method was applied to learn the atomic connectome patterns (ACPs) of both task-free and task-performance states. Experimental results demonstrated that the learned ACPs for R-fMRI and T-fMRI datasets are substantially different, as expected. A certain portion of ACPs from R-fMRI and T-fMRI data were overlapped, suggesting some subjects with overlapping ACPs were not in the expected task-free/task-performance brain states. Besides, potential outliers in the T-fMRI dataset were further investigated via functional activation detections in different groups, and our results revealed unexpected task-performances of some subjects. This work offers novel insights into the functional architectures of the brain.

  18. Influence of Force and Torque Feedback on Operator Performance in a VR-Based Suturing Task

    Directory of Open Access Journals (Sweden)

    L. Santos-Carreras

    2010-01-01

    Full Text Available The introduction of Minimally Invasive Surgery (MIS has revolutionised surgical care, considerably improving the quality of many surgical procedures. Technological advances, particularly in robotic surgery systems, have reduced the complexity of such an approach, paving the way for even less invasive surgical trends. However, the fact that haptic feedback has been progressively lost through this transition is an issue that to date has not been solved. Whereas traditional open surgery provides full haptic feedback, the introduction of MIS has eliminated the possibility of direct palpation and tactile exploration. Nevertheless, these procedures still provide a certain amount of force feedback through the rigid laparoscopic tool. Many of the current telemanipulated robotic surgical systems in return do not provide full haptic feedback, which to a certain extent can be explained by the requirement of force sensors integrated into the tools of the slave robot and actuators in the surgeon’s master console. In view of the increased complexity and cost, the benefit of haptic feedback is open to dispute. Nevertheless, studies have shown the importance of haptic feedback, especially when visual feedback is unreliable or absent. In order to explore the importance of haptic feedback for the surgeon’s master console of a novel teleoperated robotic surgical system, we have identified a typical surgical task where performance could potentially be improved by haptic feedback, and investigate performance with and without this feedback. Two rounds of experiments are performed with 10 subjects, six of them with a medical background. Results show that feedback conditions, including force feedback, significantly improve task performance independently of the operator’s suturing experience. There is, however, no further significant improvement when torque feedback is added. Consequently, it is deduced that force feedback in translations improves subject

  19. Lost ability to automatize task performance in old age.

    Science.gov (United States)

    Maquestiaux, François; Didierjean, André; Ruthruff, Eric; Chauvel, Guillaume; Hartley, Alan

    2013-12-01

    Can elderly adults automatize a new task? To address this question, 10 older adults each performed 10,080 training trials over 12 sessions on an easy but novel task. The psychological refractory period (PRP) procedure was then used to evaluate whether this highly practiced task, when presented as task 2 along with an unpracticed task 1, could proceed automatically. If automatic, task 2 processing should bypass the bottleneck and, therefore, not be delayed while central attention is devoted to task 1, yielding little dual-task interference. This is exactly what Maquestiaux, Laguë-Beauvais, Ruthruff, and Bherer (Memory and Cognition 36:1262-1282, 2008) previously observed for almost all younger adults, even with half the training on a more difficult task. Although extensive training reduced older adults' reaction times to only 307 ms, a value virtually identical to that attained by Maquestiaux et al.'s (Memory and Cognition 36:1262-1282, 2008) younger adults, the highly practiced task 2 was slowed by 485 ms in the dual-task PRP procedure. Such a large slowing in older adults is striking given the easy tasks and massive amounts of practice. These findings demonstrate a qualitative change with age, in which older adults lose the ability to automatize novel tasks, which cannot be attributed merely to generalized cognitive slowing.

  20. Task-free MRI predicts individual differences in brain activity during task performance.

    Science.gov (United States)

    Tavor, I; Parker Jones, O; Mars, R B; Smith, S M; Behrens, T E; Jbabdi, S

    2016-04-01

    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects.

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

    Science.gov (United States)

    van der Geer, Eric; van Tuijl, Harrie F J M; Rutte, Christel G

    2009-11-01

    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 performance indicators. We report findings from a field study in a medical rehabilitation centre in The Netherlands, where four low task uncertain teams ('hand trauma', 'heart failure', 'amputation', 'chronic pain'), and four high task uncertain teams ('children with developmental coordination disorders (DCD)', 'parkinson's disease', 'young children (0-4 years) with developmental disorders', and 'acquired brain injuries') participated in the development of performance indicators using the Productivity Measurement and Enhancement System (ProMES) method. Results show that teams higher on task uncertainty developed relatively more process indicators compared to outcome indicators, whereas the reverse was true for teams lower on task uncertainty. Additionally, process indicators developed by high task uncertain teams were more of a problem solving nature than process indicators developed by low task uncertain teams, which had a more procedural character. The study expands existing knowledge by providing a framework which explicates the task processes to be executed under different levels of task uncertainty, and in line with that appropriate performance indicators for healthcare teams.

  2. Sex Differences in Group Interaction and Task Performance.

    Science.gov (United States)

    Wood, Wendy; And Others

    Research on gender differences in group performance suggests that males excel at brainstorming while females excel at human relations and integration. To investigate the relations among gender, interaction style, and task performance, 264 college students (130 female, 134 male) worked in three person same sex groups on a production task which…

  3. Objective evaluation of the effect of noise on the performance of a complex laparoscopic task.

    Science.gov (United States)

    Moorthy, K; Munz, Y; Undre, S; Darzi, A

    2004-07-01

    Noise in operating rooms has been found to be much higher than the recommended level of 45 dB. The aim of this study was to objectively evaluate the effect of noise and music on the performance of a complex surgical task. Twelve surgeons with varying experience in laparoscopic suturing undertook 3 sutures in a laparoscopic trainer under 3 conditions: quiet, noise at 80 to 85 dB, and music. Other than the test conditions, all other conditions were standardized. A validated motion analysis system was used to assess performance. The tasks were recorded by video and played back to 2 blinded observers who rated the surgeons' performance on a global rating scale by observing the tasks for accuracy, knot quality, and number of nonpurposeful movements. Time taken for the tasks (P=.78), total number of movements (P=.78), total path length (P=.47), global score (P=.54), accuracy, and knot quality remained unchanged across the 3 conditions. The main study measures had a high test-retest reliability and internal consistency. No learning effect was seen across the 3 conditions. Surgeons can effectively "block out" noise and music. This is probably due to the high levels of concentration required for the performance of a complex surgical task. Future research should focus on the effect of these conditions on communication in the operating room.

  4. Emotional reactivity and awareness of task performance in Alzheimer's disease.

    Science.gov (United States)

    Mograbi, Daniel C; Brown, Richard G; Salas, Christian; Morris, Robin G

    2012-07-01

    Lack of awareness about performance in tasks is a common feature of Alzheimer's disease. Nevertheless, clinical anecdotes have suggested that patients may show emotional or behavioural responses to the experience of failure despite reporting limited awareness, an aspect which has been little explored experimentally. The current study investigated emotional reactions to success or failure in tasks despite unawareness of performance in Alzheimer's disease. For this purpose, novel computerised tasks which expose participants to systematic success or failure were used in a group of Alzheimer's disease patients (n=23) and age-matched controls (n=21). Two experiments, the first with reaction time tasks and the second with memory tasks, were carried out, and in each experiment two parallel tasks were used, one in a success condition and one in a failure condition. Awareness of performance was measured comparing participant estimations of performance with actual performance. Emotional reactivity was assessed with a self-report questionnaire and rating of filmed facial expressions. In both experiments the results indicated that, relative to controls, Alzheimer's disease patients exhibited impaired awareness of performance, but comparable differential reactivity to failure relative to success tasks, both in terms of self-report and facial expressions. This suggests that affective valence of failure experience is processed despite unawareness of task performance, which might indicate implicit processing of information in neural pathways bypassing awareness. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. 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

    2014-07-01

    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, after a short or long interval, by a digit to which 1 of 2 responses was required. In a tasks condition, participants were (as usual) directed to interpret the cue as an instruction to perform either an odd/even or a high/low classification task. In a cue + stimulus → response (CSR) condition, to induce learning of mappings between cue-stimulus compound and response, participants were, in Experiment 1, given standard task instructions and additionally encouraged to learn the CSR mappings; in Experiment 2, informed of all the CSR mappings and asked to learn them, without standard task instructions; in Experiment 3, required to learn the mappings by trial and error. The effects of a task switch, response congruence, preparation, and transfer to a new set of stimuli differed substantially between the conditions in ways indicative of classification according to task rules in the tasks condition, and retrieval of responses specific to stimulus-cue combinations in the CSR conditions. Qualitative features of the latter could be captured by an associative learning network. Hence associatively based compound retrieval can serve as the basis for performance with a small stimulus set. But when organization by tasks is apparent, control via task set selection is the natural and efficient strategy.

  6. Task-free MRI predicts individual differences in brain activity during task performance

    NARCIS (Netherlands)

    Tavor, I.; Jones, O.P.; Mars, R.B.; Smith, S.M.; Behrens, T.E.J.; Jbabdi, S.

    2016-01-01

    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent

  7. The curvilinear relationship between state neuroticism and momentary task performance.

    Directory of Open Access Journals (Sweden)

    Jonas Debusscher

    Full Text Available 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.

  8. 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.

  9. 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.

  10. 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.

  11. Task Performance and Interpersonal Attraction in Children.

    Science.gov (United States)

    Levine, John M.; And Others

    1982-01-01

    Reports two studies investigating how performance information affects interpersonal attraction in children. In both experiments children worked on perceptual problems in simulated groups, received feedback about their own and other group members' performance, and then indicated their desire to interact with selected group members in various…

  12. 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...

  13. Dual task performance in normal aging: a comparison of choice reaction time tasks.

    Directory of Open Access Journals (Sweden)

    Eleftheria Vaportzis

    Full Text Available This study examined dual task performance in 28 younger (18-30 years and 28 older (>60 years adults using two sets of choice reaction time (RT tasks paired with digit tasks. Set one paired simple choice RT with digit forward; set two paired complex choice RT with digit backward. Each task within each set had easy and hard conditions. For the simple choice RT, participants viewed single letters and pressed a specified keyboard key if the letter was X or Z or a different key for other letters (easy. For the hard condition, there were 4 target letters (X, Z, O, Y. Digit forward consisted of 4 (easy or 5 (hard digits. For the complex choice RT, participants viewed 4×4 matrices of Xs and Os, and indicated whether four Xs (easy or four Xs or four Os (hard appeared in a row. Digit backward consisted of 3 (easy or 4 (hard digits. Within each set, participants performed every possible combination of tasks. We found that in the simple choice RT tasks older adults were significantly slower than, but as accurate as younger adults. In the complex choice RT tasks, older adults were significantly less accurate, but as fast as younger adults. For both age groups and both dual task sets, RT decreased and error rates increased with greater task difficulty. Older adults had greater dual task costs for error rates in the simple choice RT, whereas in the complex choice RT, it was the younger group that had greater dual task costs. Findings suggest that younger and older adults may adopt differential behavioral strategies depending on complexity and difficulty of dual tasks.

  14. Effect of Redundant Haptic Information on Task Performance during Visuo-Tactile Task Interruption and Recovery.

    Science.gov (United States)

    Moon, Hee-Seung; Baek, Jongsoo; Seo, Jiwon

    2016-01-01

    Previous studies have revealed that interruption induces disruptive influences on the performance of cognitive tasks. While much research has focused on the use of multimodal channels to reduce the cost of interruption, few studies have utilized haptic information as more than an associative cue. In the present study, we utilized a multimodal task interruption scenario involving the simultaneous presentation of visual information and haptic stimuli in order to investigate how the combined stimuli affect performance on the primary task (cost of interruption). Participants were asked to perform a two-back visuo-tactile task, in which visual and haptic stimuli were presented simultaneously, which was interrupted by a secondary task that also utilized visual and haptic stimuli. Four experimental conditions were evaluated: (1) paired information (visual stimulus + paired haptic stimulus) with interruption; (2) paired information without interruption; (3) non-paired information (visual stimulus + non-paired haptic stimulus) with interruption; and (4) non-paired information without interruption. Our findings indicate that, within a visuo-tactile task environment, redundant haptic information may not only increase accuracy on the primary task but also reduce the cost of interruption in terms of accuracy. These results suggest a new way of understanding the task recovery process within a multimodal environment.

  15. Effect of Redundant Haptic Information on Task Performance During Visuo-Tactile Task Interruption and Recovery

    Directory of Open Access Journals (Sweden)

    Hee-Seung Moon

    2016-12-01

    Full Text Available Previous studies have revealed that interruption induces disruptive influences on the performance of cognitive tasks. While much research has focused on the use of multimodal channels to reduce the cost of interruption, few studies have utilized haptic information as more than an associative cue. In the present study, we utilized a multimodal task interruption scenario involving the simultaneous presentation of visual information and haptic stimuli in order to investigate how the combined stimuli affect performance on the primary task (cost of interruption. Participants were asked to perform a two-back visuo-tactile task, in which visual and haptic stimuli were presented simultaneously, which was interrupted by a secondary task that also utilized visual and haptic stimuli. Four experimental conditions were evaluated: (1 paired information (visual stimulus + paired haptic stimulus with interruption; (2 paired information without interruption; (3 non-paired information (visual stimulus + non-paired haptic stimulus with interruption; and (4 non-paired information without interruption. Our findings indicate that, within a visuo-tactile task environment, redundant haptic information may not only increase accuracy on the primary task but also reduce the cost of interruption in terms of accuracy. These results suggest a new way of understanding the task recovery process within a multimodal environment.

  16. Performance of machine learning methods for classification tasks

    OpenAIRE

    B. Krithika; Dr. V. Ramalingam; Rajan, K

    2013-01-01

    In this paper, the performance of various machine learning methods on pattern classification and recognition tasks are proposed. The proposed method for evaluating performance will be based on the feature representation, feature selection and setting model parameters. The nature of the data, the methods of feature extraction and feature representation are discussed. The results of the Machine Learning algorithms on the classification task are analysed. The performance of Machine Learning meth...

  17. 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.

  18. Modeling Cognitive Strategies during Complex Task Performing Process

    Science.gov (United States)

    Mazman, Sacide Guzin; Altun, Arif

    2012-01-01

    The purpose of this study is to examine individuals' computer based complex task performing processes and strategies in order to determine the reasons of failure by cognitive task analysis method and cued retrospective think aloud with eye movement data. Study group was five senior students from Computer Education and Instructional Technologies…

  19. Effects of a Coactor's Focus of Attention on Task Performance

    Science.gov (United States)

    Bockler, Anne; Knoblich, Gunther; Sebanz, Natalie

    2012-01-01

    Coactors take into account certain aspects of each other's tasks even when this is not required to perform their own task. The present experiments investigated whether the way a coactor allocates attention affects one's own attentional relation to stimuli that are attended jointly (Experiment 1), individually (Experiment 2), or in parallel…

  20. Criterion-based (proficiency) training to improve surgical performance.

    Science.gov (United States)

    Fried, Marvin P; Kaye, Rachel J; Gibber, Marc J; Jackman, Alexis H; Paskhover, Boris P; Sadoughi, Babak; Schiff, Bradley; Fraioli, Rebecca E; Jacobs, Joseph B

    2012-11-01

    OBJECTIVE To investigate whether training otorhinolaryngology residents to criterion performance levels (proficiency) on the Endoscopic Sinus Surgery Simulator produces individuals whose performance in the operating room is at least equal to those who are trained by performing a fixed number of surgical procedures. DESIGN Prospective cohort. SETTING Two academic medical centers in New York City. PARTICIPANTS Otorhinolaryngology junior residents composed of 8 experimental subjects and 6 control subjects and 6 attending surgeons. INTERVENTION Experimental subjects achieved benchmark proficiency criteria on the Endoscopic Sinus Surgery Simulator; control subjects repeated the surgical procedure twice. MAIN OUTCOME MEASURES Residents completed validated objective tests to assess baseline abilities. All subjects were videotaped performing an initial standardized surgical procedure. Residents were videotaped performing a final surgery. Videotapes were assessed for metrics by an expert panel. RESULTS Attendings outperformed the residents in most parameters on the initial procedure. Experimental and attending groups outperformed controls in some parameters on the final procedure. There was no difference between resident groups in initial performance, but the experimental subjects outperformed the control subjects in navigation in the final procedure. Most important, there was no difference in final performance between subgroups of the experimental group on the basis of the number of trials needed to attain proficiency. CONCLUSIONS Simulator training can improve resident technical skills so that each individual attains a proficiency level, despite the existence of an intrinsic range of abilities. This proficiency level translates to at least equal, if not superior, operative performance compared with that of current conventional training with finite repetition of live surgical procedures.

  1. Nicotine improves antisaccade task performance without affecting prosaccades.

    Science.gov (United States)

    Larrison, Abigail L; Briand, Kevin A; Sereno, Anne B

    2004-08-01

    Although there is ample evidence for a cognitive-attentional benefit of the stimulant nicotine, the source of this benefit is not as well understood. One approach is to address what aspects of performance nicotine affects at a functional systems level. It is currently debated whether the benefits produced by nicotine are the effect of enhanced higher cognitive function or reflect an overall increase in general arousal. In order to address this question, the effects of nicotine on two simple eye movement tasks were studied: the saccade (S) and antisaccade (AS) tasks. Because the S and AS tasks utilize identical sensory stimuli (peripheral targets) and require identical motor responses (eye movements) but differ significantly in their cognitive demands, the use of these two tasks should enable a parsing of nicotine effects on cognitive versus sensory-motor processes. In this study, the S and AS tasks were performed by two experimental groups, task naïve subjects and highly practised subjects. For the first group, that of the task naïve subjects, nicotine gum administration resulted in a decrease in AS errors. For the second group, that of two experienced subjects tested repeatedly over a 3 week period, nicotine also produced a significant decrease in AS task errors, as well as resulting in a significant decrease in AS response times. Neither task naïve nor experienced subjects showed any effects of nicotine on the S task. Examining the effects of nicotine on highly controlled and constrained tasks such as the S and AS task may provide another level of insight into the mechanisms underlying the beneficial cognitive effects of nicotine. Copyright 2004 John Wiley & Sons, Ltd.

  2. LED Surgical Task Lighting Scoping Study: A Hospital Energy Alliance Project

    Energy Technology Data Exchange (ETDEWEB)

    Tuenge, Jason R.

    2011-01-17

    Tungsten-halogen (halogen) lamps have traditionally been used to light surgical tasks in hospitals, even though they are in many respects ill-suited to the application due to the large percentage of radiant energy outside the visible spectrum and issues with color rendering/quality. Light-emitting diode (LED) technology offers potential for adjustable color and improved color rendition/quality, while simultaneously reducing side-effects from non-visible radiant energy. It also has the potential for significant energy savings, although this is a fairly narrow application in the larger commercial building energy use sector. Based on analysis of available products and Hospital Energy Alliance member interest, it is recommended that a product specification and field measurement procedure be developed for implementation in demonstration projects.

  3. An assessment of the physical impact of complex surgical tasks on surgeon errors and discomfort: a comparison between robot-assisted, laparoscopic and open approaches.

    Science.gov (United States)

    Elhage, Oussama; Challacombe, Ben; Shortland, Adam; Dasgupta, Prokar

    2015-02-01

    To evaluate, in a simulated suturing task, individual surgeons’ performance using three surgical approaches: open, laparoscopic and robot-assisted. subjects and methods: Six urological surgeons made an in vitro simulated vesico-urethral anastomosis. All surgeons performed the simulated suturing task using all three surgical approaches (open, laparoscopic and robot-assisted). The time taken to perform each task was recorded. Participants were evaluated for perceived discomfort using the self-reporting Borg scale. Errors made by surgeons were quantified by studying the video recording of the tasks. Anastomosis quality was quantified using scores for knot security, symmetry of suture, position of suture and apposition of anastomosis. The time taken to complete the task by the laparoscopic approach was on average 221 s, compared with 55 s for the open approach and 116 s for the robot-assisted approach (anova, P errors and the level of self-reported discomfort were highest for the laparoscopic approach (anova, P robot-assisted surgery combines the accuracy of open surgery while causing lesser surgeon discomfort than laparoscopy and maintaining minimal access.

  4. 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.

  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

    2016-08-31

    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. 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.

  7. 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.

  8. Physical Activity Predicts Performance in an Unpracticed Bimanual Coordination Task

    Science.gov (United States)

    Boisgontier, Matthieu P.; Serbruyns, Leen; Swinnen, Stephan P.

    2017-01-01

    Practice of a given physical activity is known to improve the motor skills related to this activity. However, whether unrelated skills are also improved is still unclear. To test the impact of physical activity on an unpracticed motor task, 26 young adults completed the international physical activity questionnaire and performed a bimanual coordination task they had never practiced before. Results showed that higher total physical activity predicted higher performance in the bimanual task, controlling for multiple factors such as age, physical inactivity, music practice, and computer games practice. Linear mixed models allowed this effect of physical activity to be generalized to a large population of bimanual coordination conditions. This finding runs counter to the notion that generalized motor abilities do not exist and supports the existence of a “learning to learn” skill that could be improved through physical activity and that impacts performance in tasks that are not necessarily related to the practiced activity. PMID:28265253

  9. 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.; Phillips, T.; Ploutz-Snyder, L. L.; Reschke, M. F.; Ryder, J. W.; Spiering, B. A.; Stenger, M. B.; Taylor, L. C.; Wickwire, P. J.; Wood, S. J.

    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.

  10. 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. 

  11. Coupling of postural and manual tasks in expert performers.

    Science.gov (United States)

    Amado, A C; Palmer, C J; Hamill, J; van Emmerik, R E A

    2016-04-01

    The purpose of this study was to investigate the integration of bimanual rhythmic movements and posture in expert marching percussionists. Participants (N=11) performed three rhythmic manual tasks [1:1, 2:3, and 2:3-F (2:3 rhythm played faster at a self-selected tempo)] in one of three postures: sitting, standing on one foot, and standing on two feet. Discrete relative phase, postural time-to-contact, and coherence analysis were used to analyze the performance of the manual task, postural control, and the integration between postural and manual performance. Across all three rhythms, discrete relative phase mean and variability results showed no effects of posture on rhythmic performance. The complexity of the manual task (1:1 vs. 2:3) had no effect on postural time-to-contact. However, increasing the tempo of the manual task (2:3 vs. 2:3-F) did result in a decreased postural time-to-contact in the two-footed posture. Coherence analysis revealed that the coupling between the postural and manual task significantly decreased as a function of postural difficulty (going from a two-footed to a one-footed posture) and rhythmic complexity (1:1 vs. 2:3). Taken together, these results demonstrate that expert marching percussionists systematically decouple postural and manual fluctuations in order to preserve the performance of the rhythmic movement task.

  12. Luminance controlled pupil size affects Landolt C task performance. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Berman, S.M. [Lawrence Berkeley Lab., CA (United States); Fein, G. [Neurobehavioral Lab. Software, San Rafael, CA (United States); Jewett, D.L.; Ashford, F. [ABRATech Corp., Mill Valley, CA (United States)

    1993-02-01

    Subjects judged the orientation of a 2 min. gap Landolt C located at a distance of 2.4 m. The stimuli were presented in central vision on a CRT, at low to medium contrast. The effects of varying the spectrum and luminance of surround lighting were assessed on both pupil size (measured using infrared pupillometry during task performance) and task accuracy. The task display was protected from the surround lighting, so that its luminance and contrast could be varied independently of the changes in the surround lighting. Indirect surround illumination was provided by either two illuminants of very different scotopic spectral content but with the same photopic luminance (Experiments 1 and 3), or by using the same illuminant at two different luminance levels (Experiment 2). In Experiment 3, the effect of changing surround spectrum was compared to the effect of varying task background luminance between 12 cd/m{sup 2} and 73 cd/m{sup 2}. In all experiments, scotopically enhanced surround lighting produced pupil areas which were reduced by almost 50% in comparison with surround lighting with relatively less scotopic luminance. Concomitantly there was improvement in Landolt C task performance with the scotopically enhanced surround lighting at all contrast and luminance levels. In these experiments, smaller pupil sizes were associated with significantly better visual-task performance in spite of lower task retinal illuminance when compared to the condition with larger pupils. These results suggest that changes in surround spectrum can compensate for the effect on task performance of a reduction in task luminance and supports the hypothesis that lighting energy savings could accrue in the workplace by shifting lamp spectra to obtain greater scotopic efficacy.

  13. Luminance controlled pupil size affects Landolt C task performance

    Energy Technology Data Exchange (ETDEWEB)

    Berman, S.M. (Lawrence Berkeley Lab., CA (United States)); Fein, G. (Neurobehavioral Lab. Software, San Rafael, CA (United States)); Jewett, D.L.; Ashford, F. (ABRATech Corp., Mill Valley, CA (United States))

    1993-02-01

    Subjects judged the orientation of a 2 min. gap Landolt C located at a distance of 2.4 m. The stimuli were presented in central vision on a CRT, at low to medium contrast. The effects of varying the spectrum and luminance of surround lighting were assessed on both pupil size (measured using infrared pupillometry during task performance) and task accuracy. The task display was protected from the surround lighting, so that its luminance and contrast could be varied independently of the changes in the surround lighting. Indirect surround illumination was provided by either two illuminants of very different scotopic spectral content but with the same photopic luminance (Experiments 1 and 3), or by using the same illuminant at two different luminance levels (Experiment 2). In Experiment 3, the effect of changing surround spectrum was compared to the effect of varying task background luminance between 12 cd/m[sup 2] and 73 cd/m[sup 2]. In all experiments, scotopically enhanced surround lighting produced pupil areas which were reduced by almost 50% in comparison with surround lighting with relatively less scotopic luminance. Concomitantly there was improvement in Landolt C task performance with the scotopically enhanced surround lighting at all contrast and luminance levels. In these experiments, smaller pupil sizes were associated with significantly better visual-task performance in spite of lower task retinal illuminance when compared to the condition with larger pupils. These results suggest that changes in surround spectrum can compensate for the effect on task performance of a reduction in task luminance and supports the hypothesis that lighting energy savings could accrue in the workplace by shifting lamp spectra to obtain greater scotopic efficacy.

  14. 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.

  15. Building surgical capacity in low-resource countries: a qualitative analysis of task shifting from surgeon volunteers' perspectives.

    Science.gov (United States)

    Aliu, Oluseyi; Corlew, Scott D; Heisler, Michele E; Pannucci, Christopher J; Chung, Kevin C

    2014-01-01

    Surgical volunteer organizations (SVOs) focus considerable resources on addressing the backlog of cases in low-resource countries. This model of service may perpetuate dependency. Efforts should focus on models that establish independence in providing surgical care. Independence could be achieved through surgical capacity building. However, there has been scant discussion in literature on SVO involvement in surgical capacity building. Using qualitative methods, we evaluated the perspectives of surgeons with extensive volunteer experience in low-resource countries. We collected data through in-depth interviews that centered on SVOs using task shifting as a tool for surgical capacity building. Some of the key themes from our analysis include the ethical ramifications of task shifting, the challenges of addressing technical and clinical education in capacity building for low-resource settings, and the allocation of limited volunteer resources toward surgical capacity building. These themes will be the foundation of subsequent studies that will focus on other stakeholders in surgical capacity building including host communities and SVO administrators.

  16. 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.

  17. 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...

  18. Effects of task repetition on L2 oral performance

    OpenAIRE

    Finardi, Kyria Rebeca

    2008-01-01

    This study departs from the assumption that speaking an L2 is a complex cognitive ability (FORTKAMP, 2000) whose execution seems to involve tradeoff effects among the different goals of speech production, mainly among fluency, accuracy and complexity (BYGATE, 1998, 1999, 2001b; FOSTER e SKEHAN, 1996; SKEHAN e FOSTER, 1995, 2001; SKEHAN, 1998). Bygate (2001b) studied the effects of task familiarity on L2 speech performance. He found that in repeating a narrative task there were gains in terms ...

  19. 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

  20. Ergonomic factors on task performance in laparoscopic surgery training.

    Science.gov (United States)

    Xiao, D J; Jakimowicz, Jack J; Albayrak, A; Goossens, R H M

    2012-05-01

    This paper evaluates the effect of ergonomic factors on task performance and trainee posture during laparoscopic surgery training. Twenty subjects without laparoscopic experience were allotted into 2 groups. Group 1 was trained under the optimal ergonomic simulation setting according to current ergonomic guidelines (Condition A). Group 2 was trained under non-optimal ergonomic simulation setting that can often be observed during training in a skills lab (Condition B). Posture analysis showed that the subjects held a much more neutral posture under Condition A than under Condition B (poptimal ergonomic simulation setting leads to better task performance. In addition, no significant differences of task performance, for Groups 1 and 2 using the same test setting were found. However, better performance was observed for Group 1. It can be concluded that the optimal and non-optimal training setting have different learning effects on trainees' skill learning.

  1. Background music for repetitive task performance of severely retarded individuals.

    Science.gov (United States)

    Richman, J S

    1976-11-01

    Environmental manipulation in the form of specific tempo background music was used to assist in the habilitation of severely retarded persons. Thirty institutionalized retarded males were tested on a repetitive manual performance task judged to be similar to the type of tasks found in sheltered workshops. Each subject received each of the background treatments noncontingently: no music, slow tempo music, regular tempo music, fast tempo music. The results indicated that the regular tempo of background music facilitated the greatest improvement in performance, suggesting that the effect of music on performance is more complex than the issue of contingent presentation.

  2. Computer task performance by subjects with Duchenne muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Malheiros SRP

    2015-12-01

    Full Text Available Silvia Regina Pinheiro Malheiros,1 Talita Dias da Silva,2 Francis Meire Favero,2 Luiz Carlos de Abreu,1 Felipe Fregni,3 Denise Cardoso Ribeiro,4 Carlos Bandeira de Mello Monteiro1,4,5 1School of Medicine of ABC, Santo Andre, Brazil; 2Department of Medicine, Paulista School of Medicine, Federal University of São Paulo, São Paulo, Brazil; 3Center for Neurosciences, University of São Paulo, São Paulo, Brazil; 4Post-graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of São Paulo, São Paulo, Brazil; 5School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil Aims: 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.Method: 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.Results: 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.Conclusion: DMD participants improved their performance after practicing

  3. Compensatory mechanisms underlie intact task-switching performance in schizophrenia.

    Science.gov (United States)

    Jamadar, S; Michie, P; Karayanidis, F

    2010-04-01

    Individuals with schizophrenia tend to perform poorly on many measures of cognitive control. However, recent task-switching studies suggest that they show intact task-switching performance, despite the fact that the regions involved in task-switching are known to be structurally and functionally impaired in the disorder. Behavioral, event-related potential (ERP) and functional magnetic resonance imaging (fMRI) measures were used to compare the temporal and spatial dynamics of task-switching performance in individuals with schizophrenia and controls. Consistent with previous studies, reaction time (RT) switch cost and its reduction with anticipatory preparation did not differ between groups. There were also no group differences on cue-locked ERP components associated with anticipatory preparation processes. However, both stimulus- and response-locked ERPs were significantly disrupted in schizophrenia, suggesting difficulty with task-set implementation. fMRI analyses indicated that individuals with schizophrenia showed hyperactivity in the dorsolateral prefrontal cortex and posterior parietal cortex. RT-fMRI and ERP-fMRI associations suggested that individuals with schizophrenia employ compensatory mechanisms to overcome difficulties in task-set implementation and thereby achieve the same behavioral outcomes as controls.

  4. Surgical tracheotomy performed with and without dual antiplatelet therapy.

    Science.gov (United States)

    Markota, Andrej; Sinkovič, Andreja; Čizmarević, Bogdan

    2015-01-01

    Some patients who need dual antiplatelet therapy sometimes require tracheotomy. Aim of this study was to compare the rate of complications during and after surgical tracheotomy between patients requiring dual antiplatelet therapy and those without dual antiplatelet therapy. We retrospectively included 79 patients (62% men, mean age 64 ± 14 years) in the period 2007-2011. The following complications were analyzed: need for surgical revision within 24 hours after tracheotomy, need for bronchoscopy within 24 hour after tracheotomy, need for blood transfusion within 24 hours after tracheotomy, death attributed to tracheotomy and any complication attributed to tracheotomy. We compared patients where tracheotomy was performed while receiving dual antiplatelet therapy (n=27, 34%) to patients where tracheotomy was performed without dual antiplatelet therapy (n=52, 66%). Nonsignificant differences between the two groups were observed general characteristics. There were no statistically significant differences in complications after tracheotomy (surgical revision after tracheotomy p=0.63, bronchoscopy after tracheotomy p=0.74, blood transfusion after tracheotomy p=0.59, death attributed to tracheotomy p=1.00 and any complication attributed to tracheotomy p=1.00). The study shows that tracheotomy is safe in cardiac patients on dual antiplatelet therapy.

  5. Situation awareness and driving performance in a simulated navigation task.

    Science.gov (United States)

    Ma, R; Kaber, D B

    2007-08-01

    The objective of this study was to identify task and vehicle factors that may affect driver situation awareness (SA) and its relationship to performance, particularly in strategic (navigation) tasks. An experiment was conducted to assess the effects of in-vehicle navigation aids and reliability on driver SA and performance in a simulated navigation task. A total of 20 participants drove a virtual car and navigated a large virtual suburb. They were required to follow traffic signs and navigation directions from either a human aid via a mobile phone or an automated aid presented on a laptop. The navigation aids operated under three different levels of information reliability (100%, 80% and 60%). A control condition was used in which each aid presented a telemarketing survey and participants navigated using a map. Results revealed perfect navigation information generally improved driver SA and performance compared to unreliable navigation information and the control condition (task-irrelevant information). In-vehicle automation appears to mediate the relationship of driver SA to performance in terms of operational and strategic (navigation) behaviours. The findings of this work support consideration of driver SA in the design of future vehicle automation for navigation tasks.

  6. Human task animation from performance models and natural language input

    Science.gov (United States)

    Esakov, Jeffrey; Badler, Norman I.; Jung, Moon

    1989-01-01

    Graphical manipulation of human figures is essential for certain types of human factors analyses such as reach, clearance, fit, and view. In many situations, however, the animation of simulated people performing various tasks may be based on more complicated functions involving multiple simultaneous reaches, critical timing, resource availability, and human performance capabilities. One rather effective means for creating such a simulation is through a natural language description of the tasks to be carried out. Given an anthropometrically-sized figure and a geometric workplace environment, various simple actions such as reach, turn, and view can be effectively controlled from language commands or standard NASA checklist procedures. The commands may also be generated by external simulation tools. Task timing is determined from actual performance models, if available, such as strength models or Fitts' Law. The resulting action specification are animated on a Silicon Graphics Iris workstation in real-time.

  7. Stress and the Measurement of Task Performance. I. Decision Making in Complex Tasks.

    Science.gov (United States)

    1981-05-01

    P. R. The effect of crowding on human task performance. Journal of Applied Social Psychology , 1971, 1, 7-25. Higbee, K. L. Expression of "Walter...uncontrollable and unpredictable noise. Journal of Applied Social Psychology , 1971, 1, 44-56 Schroder, H. M., Driver, M. J. and Streufert, S. Human

  8. 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...

  9. Beyond task performance: the concept of organizational citizenship performance

    Directory of Open Access Journals (Sweden)

    Walter C. Borman

    2008-01-01

    Full Text Available In this paper, we describe the construct of citizenship performance and briefly review some of the industrial and organizational psychology research on organizational citizenship. We discuss the history, the dimensionality, the antecedents, consequences and implications for practice, and also provide a critical analysis. The conclusions of this review are that citizenship performance is important for contemporary organizations and contemporary trends suggest it will continue to be important in the future. We encourage further research in the area of citizenship performance in other cultures beyond the US.

  10. 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.

  11. Notes From the Field: Secondary Task Precision for Cognitive Load Estimation During Virtual Reality Surgical Simulation Training.

    Science.gov (United States)

    Rasmussen, Sebastian R; Konge, Lars; Mikkelsen, Peter T; Sørensen, Mads S; Andersen, Steven A W

    2016-03-01

    Cognitive load (CL) theory suggests that working memory can be overloaded in complex learning tasks such as surgical technical skills training, which can impair learning. Valid and feasible methods for estimating the CL in specific learning contexts are necessary before the efficacy of CL-lowering instructional interventions can be established. This study aims to explore secondary task precision for the estimation of CL in virtual reality (VR) surgical simulation and also investigate the effects of CL-modifying factors such as simulator-integrated tutoring and repeated practice. Twenty-four participants were randomized for visual assistance by a simulator-integrated tutor function during the first 5 of 12 repeated mastoidectomy procedures on a VR temporal bone simulator. Secondary task precision was found to be significantly lower during simulation compared with nonsimulation baseline, p precision. This finding suggests that even though considerable changes in CL are reflected in secondary task precision, it lacks sensitivity. In contrast, secondary task reaction time could be more sensitive, but requires substantial postprocessing of data. Therefore, future studies on the effect of CL modifying interventions should weigh the pros and cons of the various secondary task measurements.

  12. Dynamic Task Performance, Cohesion, and Communications in Human Groups.

    Science.gov (United States)

    Giraldo, Luis Felipe; Passino, Kevin M

    2016-10-01

    In the study of the behavior of human groups, it has been observed that there is a strong interaction between the cohesiveness of the group, its performance when the group has to solve a task, and the patterns of communication between the members of the group. Developing mathematical and computational tools for the analysis and design of task-solving groups that are not only cohesive but also perform well is of importance in social sciences, organizational management, and engineering. In this paper, we model a human group as a dynamical system whose behavior is driven by a task optimization process and the interaction between subsystems that represent the members of the group interconnected according to a given communication network. These interactions are described as attractions and repulsions among members. We show that the dynamics characterized by the proposed mathematical model are qualitatively consistent with those observed in real-human groups, where the key aspect is that the attraction patterns in the group and the commitment to solve the task are not static but change over time. Through a theoretical analysis of the system we provide conditions on the parameters that allow the group to have cohesive behaviors, and Monte Carlo simulations are used to study group dynamics for different sets of parameters, communication topologies, and tasks to solve.

  13. Rules and development in triad classification task performance.

    NARCIS (Netherlands)

    Raijmakers, M.E.J.; Jansen, B.R.J.; van der Maas, H.L.J.

    2004-01-01

    Rule use in perceptual classification was investigated in adults and in 4- to 12-year-old children. Two studies of performance on triad classification tasks with large samples (N=226 and N= 328) are presented to (a) contrast theoretical predictions from the holistic-to-analytic-shift theory (Smith &

  14. Music and Spatial Task Performance: A Causal Relationship.

    Science.gov (United States)

    Rauscher, Frances H.; And Others

    This research paper reports on testing the hypothesis that music and spatial task performance are causally related. Two complementary studies are presented that replicate and explore previous findings. One study of college students showed that listening to a Mozart sonata induces subsequent short-term spatial reasoning facilitation and tested the…

  15. THE ROLE OF PREPARATION IN OVERLAPPING-TASK PERFORMANCE

    NARCIS (Netherlands)

    de Jong, Robert (Rob)

    1995-01-01

    We examined how performance of two overlapping discrete tasks is organized and controlled. Experiment 1 showed that when stimuli were presented in an unexpected order, expectations rather than actual presentation order determined the order in which the two stimuli were processed. In Experiment 2, wh

  16. gender differences in job ability perception and task performance ...

    African Journals Online (AJOL)

    Elizabeth

    Key words: Gender differences; Job ability perception; Task performance. ... Historically, women have been differently integrated into the social and ... some professions make it difficult for several women to interact well with .... Hypothesis One: .... primary schools to choose whatever professions they want as long as they.

  17. Changes in Relevance Criteria and Problem Stages in Task Performance.

    Science.gov (United States)

    Vakkari, Pertti; Hakala, Nanna

    2000-01-01

    This study of students at the University of Tampere (Finland) analyzes how changes in relevance criteria are related to changes in problem stages during the task performance process in information retrieval. Provides a conceptual framework, including Kuhlthau's information search process model and prior knowledge; and compares bibliographic…

  18. 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...

  19. 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...

  20. 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

  1. Monitoring user-system performance in interactive retrieval tasks

    NARCIS (Netherlands)

    L. Boldareva; A.P. de Vries (Arjen); D. Hiemstra

    2004-01-01

    textabstractMonitoring 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

  2. Monitoring user-system performance in interactive retrieval tasks

    NARCIS (Netherlands)

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

    2004-01-01

    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 measur

  3. Performance of machine learning methods for classification tasks

    Directory of Open Access Journals (Sweden)

    B. Krithika

    2013-06-01

    Full Text Available In this paper, the performance of various machine learning methods on pattern classification and recognition tasks are proposed. The proposed method for evaluating performance will be based on the feature representation, feature selection and setting model parameters. The nature of the data, the methods of feature extraction and feature representation are discussed. The results of the Machine Learning algorithms on the classification task are analysed. The performance of Machine Learning methods on classifying Tamil word patterns, i.e., classification of noun and verbs are analysed.The software WEKA (data mining tool is used for evaluating the performance. WEKA has several machine learning algorithms like Bayes, Trees, Lazy, Rule based classifiers.

  4. 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…

  5. 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.

  6. Evaluation of high-definition television for remote task performance

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. 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.

  8. Some Reflections on Task-Based Language Performance Assessment.

    Science.gov (United States)

    Bachman, Lyle F.

    2002-01-01

    Discusses problems in task-based language assessment, including the definition and sampling of tasks, generalizations across tasks, interpretations about broad ability and language use domains, and the notion of task difficulty. (Author/VWL)

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

    Science.gov (United States)

    Lee, Woogul; Reeve, Johnmarshall

    2017-06-21

    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.

  10. Observer analysis and its impact on task performance modeling

    Science.gov (United States)

    Jacobs, Eddie L.; Brown, Jeremy B.

    2014-05-01

    Fire fighters use relatively low cost thermal imaging cameras to locate hot spots and fire hazards in buildings. This research describes the analyses performed to study the impact of thermal image quality on fire fighter fire hazard detection task performance. Using human perception data collected by the National Institute of Standards and Technology (NIST) for fire fighters detecting hazards in a thermal image, an observer analysis was performed to quantify the sensitivity and bias of each observer. Using this analysis, the subjects were divided into three groups representing three different levels of performance. The top-performing group was used for the remainder of the modeling. Models were developed which related image quality factors such as contrast, brightness, spatial resolution, and noise to task performance probabilities. The models were fitted to the human perception data using logistic regression, as well as probit regression. Probit regression was found to yield superior fits and showed that models with not only 2nd order parameter interactions, but also 3rd order parameter interactions performed the best.

  11. Hospital resources are associated with value-based surgical performance.

    Science.gov (United States)

    Hoehn, Richard S; Hanseman, Dennis J; Go, Derek; Wima, Koffi; Chang, Alex; Ertel, Audrey E; Shah, Shimul A; Abbott, Daniel E

    2016-07-01

    We have previously shown that inferior outcomes at safety-net hospitals are largely dependent on hospital factors. We hypothesized that hospitals providing "high value" care (low cost and better outcomes) would have advantages in human and financial resources. The University HealthSystems Consortium Clinical Database and the American Hospital Association Annual Survey were used to examine hospitals performing eight complex surgical procedures from 2009 to 2013. Hospitals in the lowest quartiles of both mortality rate and cost were characterized as high value (n = 45), whereas those in the highest quartiles of both cost and mortality were low value (n = 45). Hospital size, staffing, and financial characteristics were compared between these two groups. On average, high-value hospitals had lower proportions of Medicaid patient days (17% versus 30%; P < 0.01), higher proportions of outpatient surgery (63% versus 53%; P < 0.01), and spent more on capital expenditures per bed ($155,710 versus $62,434; P < 0.05). Also, high-value hospitals employed more hospitalists (0.08 versus 0.04 per bed; P < 0.01), had more privileged physicians (2.04 versus 1.25 per bed; P < 0.01), and had more full-time equivalent personnel (8.48 versus 6.79 per bed; all P < 0.05). As a result, these hospitals appeared to be more efficient; high-value hospitals had more total admissions per bed (46 versus 38; P < 0.01), fewer days per admission (5.20 versus 5.77; P < 0.01), and more inpatient surgeries per bed (15.7 versus 12.6; all P < 0.05). Hospitals that invest in more human resources and demonstrate increased throughput perform complex surgery at higher "value" (i.e., lower costs and mortality). Value-based purchasing initiatives that link hospital reimbursement to unadjusted surgical outcomes may exacerbate, rather than improve, disparities in surgical care that currently exist. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Task complexity and interaction: (combined) effects on task-based performance in Dutch as a second language

    NARCIS (Netherlands)

    Michel, M.C.; Kuiken, F.; Vedder, I.

    2012-01-01

    This paper presents the overarching conclusions of three consecutive investigations into task-based L2 performance. It aims at giving a better understanding of how changes in the number of elements referred to in a task affect L2 production, and how this relates to cognitive task complexity. Further

  13. 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.

  14. Visual Motor and Perceptual Task Performance in Astigmatic Students.

    Science.gov (United States)

    Harvey, Erin M; Twelker, J Daniel; Miller, Joseph M; Leonard-Green, Tina K; Mohan, Kathleen M; Davis, Amy L; Campus, Irene

    2017-01-01

    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 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.

  15. 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.

  16. 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.

  17. Temporal prediction errors modulate task-switching performance

    Directory of Open Access Journals (Sweden)

    Roberto eLimongi

    2015-08-01

    Full Text Available We have previously shown that temporal prediction errors (PEs, the differences between the expected and the actual stimulus’ onset times modulate the effective connectivity between the anterior cingulate cortex and the right anterior insular cortex (rAI, causing the activity of the rAI to decrease. The activity of the rAI is associated with efficient performance under uncertainty (e.g., changing a prepared behavior when a change demand is not expected, which leads to hypothesize that temporal PEs might disrupt behavior-change performance under uncertainty. This hypothesis has not been tested at a behavioral level. In this work, we evaluated this hypothesis within the context of task switching and concurrent temporal predictions. Our participants performed temporal predictions while observing one moving ball striking a stationary ball which bounced off with a variable temporal gap. Simultaneously, they performed a simple color comparison task. In some trials, a change signal made the participants change their behaviors. Performance accuracy decreased as a function of both the temporal PE and the delay. Explaining these results without appealing to ad-hoc concepts such as executive control is a challenge for cognitive neuroscience. We provide a predictive coding explanation. We hypothesize that exteroceptive and proprioceptive minimization of PEs would converge in a fronto-basal ganglia network which would include the rAI. Both temporal gaps (or uncertainty and temporal PEs would drive and modulate this network respectively. Whereas the temporal gaps would drive the activity of the rAI, the temporal PEs would modulate the endogenous excitatory connections of the fronto-striatal network. We conclude that in the context of perceptual uncertainty, the system is not able to minimize perceptual PE, causing the ongoing behavior to finalize and, in consequence, disrupting task switching.

  18. The Effect of Audio and Visual Aids on Task Performance in Distributed Collaborative Virtual Environments

    Science.gov (United States)

    Ullah, Sehat; Richard, Paul; Otman, Samir; Mallem, Malik

    2009-03-01

    Collaborative virtual environments (CVE) has recently gained the attention of many researchers due to its numerous potential application domains. Cooperative virtual environments, where users simultaneously manipulate objects, is one of the subfields of CVEs. In this paper we present a framework that enables two users to cooperatively manipulate objects in virtual environment, while setting on two separate machines connected through local network. In addition the article presents the use of sensory feedback (audio and visual) and investigates their effects on the cooperation and user's performance. Six volunteers subject had to cooperatively perform a peg-in-hole task. Results revealed that visual and auditory aid increase users' performance. However majority of the users preferred visual feedback to audio. We hope this framework will greatly help in the development of CAD systems that allow the designers to collaboratively design while being distant. Similarly other application domains may be cooperative assembly, surgical training and rehabilitation systems.

  19. 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,…

  20. 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.

  1. High-definition television evaluation for remote handling task performance

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. 3D straight-stick laparoscopy versus 3D robotics for task performance in novice surgeons: a randomised crossover trial.

    Science.gov (United States)

    Shakir, Fevzi; Jan, Haider; Kent, Andrew

    2016-12-01

    The advent of three-dimensional passive stereoscopic imaging has led to the development of 3D laparoscopy. In simulation tasks, a reduction in error rate and performance time is seen with 3D compared to two-dimensional (2D) laparoscopy with both novice and expert surgeons. Robotics utilises 3D and instrument articulation through a console interface. Robotic trials have demonstrated that tasks performed in 3D produced fewer errors and quicker performance times compared with those in 2D. It was therefore perceived that the main advantage of robotic surgery was in fact 3D. Our aim was to compare 3D straight-stick laparoscopic task performance (3D) with robotic 3D (Robot), to determine whether robotic surgery confers additional benefit over and above 3D visualisation. We randomised 20 novice surgeons to perform four validated surgical tasks, either with straight-stick 3D laparoscopy followed by 3D robotic surgery or in the reverse order. The trial was conducted in two fully functional operating theatres. The primary outcome of the study was the error rate as defined for each task, and the secondary outcome was the time taken to complete each task. The participants were asked to perform the tasks as quickly and as accurately as possible. Data were analysed using SPSS version 21. The median error rate for completion of all four tasks with the robot was 2.75 and 5.25 for 3D with a P value robot was 157.1 and 342.5 s for 3D with a P value robotic systems over 3D straight-stick laparoscopy, in terms of reduced error rate and quicker task performance time.

  3. Surgical virtual reality - highlights in developing a high performance surgical haptic device.

    Science.gov (United States)

    Custură-Crăciun, D; Cochior, D; Constantinoiu, S; Neagu, C

    2013-01-01

    Just like simulators are a standard in aviation and aerospace sciences, we expect for surgical simulators to soon become a standard in medical applications. These will correctly instruct future doctors in surgical techniques without there being a need for hands on patient instruction. Using virtual reality by digitally transposing surgical procedures changes surgery in are volutionary manner by offering possibilities for implementing new, much more efficient, learning methods, by allowing the practice of new surgical techniques and by improving surgeon abilities and skills. Perfecting haptic devices has opened the door to a series of opportunities in the fields of research,industry, nuclear science and medicine. Concepts purely theoretical at first, such as telerobotics, telepresence or telerepresentation,have become a practical reality as calculus techniques, telecommunications and haptic devices evolved,virtual reality taking a new leap. In the field of surgery barrier sand controversies still remain, regarding implementation and generalization of surgical virtual simulators. These obstacles remain connected to the high costs of this yet fully sufficiently developed technology, especially in the domain of haptic devices.

  4. 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.

  5. 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.

  6. A cross-sectional survey of clinicians performing periodontal surgical crown lengthening.

    Science.gov (United States)

    Wyatt, Gillian; Grey, Nick; Deery, Chris

    2004-09-01

    The aim of this study was to conduct a survey of surgical crown lengthening practice performed by dental specialists and general dental practitioners using a cross-sectional questionnaire. One hundred general dental practitioners and 100 specialists from each of the following specialties: prosthodontics, periodontics, restorative dentistry and surgical dentistry. There were fewer surgical dentists performing surgical crown lengthening than the other specialists. The specialists in periodontics were significantly more likely to perform surgical crown lengthening than not. The respondents predominantly considered that periodontal surgical crown lengthening is within the remit of periodontics. 33% of the respondents performing more than 50 PSCL procedures in one year thought that the gingival margin was stable after three months. 33% thought that it was stable after six months and 33% declined to state a post-operative marginal stability time period.

  7. Randomized clinical trial to evaluate mental practice in enhancing advanced laparoscopic surgical performance.

    Science.gov (United States)

    Louridas, M; Bonrath, E M; Sinclair, D A; Dedy, N J; Grantcharov, T P

    2015-01-01

    Mental practice, the cognitive rehearsal of a task without physical movement, is known to enhance performance in sports and music. Investigation of this technique in surgery has been limited to basic operations. The purpose of this study was to develop mental practice scripts, and to assess their effect on advanced laparoscopic skills and surgeon stress levels in a crisis scenario. Twenty senior surgical trainees were randomized to either conventional training or mental practice groups, the latter being trained by an expert performance psychologist. Participants' skills were assessed while performing a porcine laparoscopic jejunojejunostomy as part of a crisis scenario in a simulated operating room, using the Objective Structured Assessment of Technical Skill (OSATS) and bariatric OSATS (BOSATS) instruments. Objective and subjective stress parameters were measured, as well as non-technical skills using the Non-Technical Skills for Surgeons rating tool. An improvement in OSATS (P = 0.003) and BOSATS (P = 0.003) scores was seen in the mental practice group compared with the conventional training group. Seven of ten trainees improved their technical performance during the crisis scenario, whereas four of the ten conventionally trained participants deteriorated. Mental imagery ability improved significantly following mental practice training (P = 0.011), but not in the conventional group (P = 0.083). No differences in objective or subjective stress levels or non-technical skills were evident. Mental practice improves technical performance for advanced laparoscopic tasks in the simulated operating room, and allows trainees to maintain or improve their performance despite added stress. © 2014 BJS Society Ltd. Published by John Wiley & Sons Ltd.

  8. 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)…

  9. Determinants of Learning and Performance in an Associative Memory/Substitution Task: Task Constraints, Individual Differences, Volition, and Motivation.

    Science.gov (United States)

    Ackerman, Philip L.; Woltz, Dan J.

    1994-01-01

    Five experiments with 586 college students investigated how ability differences, learning task characteristics, and motivational and volitional processes combine to explain performance differences in an associative memory or substitution task. Results are discussed in terms of developing a more comprehensive understanding of learner differences.…

  10. Usage of fMRI for pre-surgical planning in brain tumor and vascular lesion patients: Task and statistical threshold effects on language lateralization

    Directory of Open Access Journals (Sweden)

    Tanvi N. Nadkarni

    2015-01-01

    Conclusion: Our results suggest that the type of task and the applied statistical threshold influence LI and that the threshold effects on LI may be task-specific. Thus identifying critical functional regions and computing LIs should be conducted on an individual subject basis, using a continuum of threshold values with different tasks to provide the most accurate information for surgical planning to minimize post-operative language deficits.

  11. Characterizing "fibrofog": Subjective appraisal, objective performance, and task-related brain activity during a working memory task.

    Science.gov (United States)

    Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L; Rayhan, Rakib; VanMeter, John W; Gracely, Richard H

    2016-01-01

    The subjective experience of cognitive dysfunction ("fibrofog") is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, "fibrofog" appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks.

  12. Recoding low-level simulator data into a record of meaningful task performance: the integrated task modeling environment (ITME).

    Science.gov (United States)

    King, Robert; Parker, Simon; Mouzakis, Kon; Fletcher, Winston; Fitzgerald, Patrick

    2007-11-01

    The Integrated Task Modeling Environment (ITME) is a user-friendly software tool that has been developed to automatically recode low-level data into an empirical record of meaningful task performance. The present research investigated and validated the performance of the ITME software package by conducting complex simulation missions and comparing the task analyses produced by ITME with taskanalyses produced by experienced video analysts. A very high interrater reliability (> or = .94) existed between experienced video analysts and the ITME for the task analyses produced for each mission. The mean session time:analysis time ratio was 1:24 using video analysis techniques and 1:5 using the ITME. It was concluded that the ITME produced task analyses that were as reliable as those produced by experienced video analysts, and significantly reduced the time cost associated with these analyses.

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

    National Research Council Canada - National Science Library

    Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

    2015-01-01

    ...‐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...

  14. Influence of gender on psychomotor vigilance task performance by adolescents

    Directory of Open Access Journals (Sweden)

    F. Beijamini

    2008-08-01

    Full Text Available During adolescence, the sleep phase delay associated with early school times increases daytime sleepiness and reduces psychomotor performance. Some studies have shown an effect of gender on psychomotor performance in adults and children. Males present faster reaction times (RT compared with females. The aim of the present study was to evaluate the influence of gender on Palm psychomotor vigilance task (PVT performance in adolescents. Thirty-four adolescents (19 girls, 13 to 16 years old attending morning school classes of a public school in Curitiba, PR, Brazil, participated in the study. Sleep patterns were measured using actigraphy and sleepiness data were accessed with the Karolinska Sleepiness Scale (KSS. KSS and PVT measurements were collected at two times in the morning (8:00 and 11:00 h. The data were compared using one-way ANOVA, considering gender as a factor. ANOVA indicated that gender did not affect sleep patterns and subjective somnolence; however, a statistically significant effect of gender was detected for PVT performance. Boys presented faster RT (RT-PVT1: 345.51 ms, F = 6.08, P < 0.05; RT-PVT2: 343.30 ms, F = 6.35, P < 0.05 and fewer lapses (lapses-PVT1: 8.71, F = 4.45, P < 0.05; lapses-PVT2: 7.82, F = 7.06, P < 0.05 compared with girls (RT-PVT1: 402.96; RT-PVT2: 415.70; lapses-PVT1: 16.33; lapses-PVT2: 17.80. These results showed that this effect of gender, already reported in adults and children, is also observed in adolescents. The influence of gender should be taken into account in studies that use Palm PVT to evaluate psychomotor performance in this age range.

  15. Self-regulation, engagement, motivation, and performance in a simulated quality control task.

    Science.gov (United States)

    Schell, Kraig L; Melton, Ellen C; Woodruff, Abbie; Corbin, G Brandon

    2004-06-01

    This study examined how self-regulation and task-related motivation were related to the accuracy of error detection and task engagement in a simulated quality control task that mimicked prescription-checking behavior in a pharmacy. Ninety-one participants completed measures of self-regulation, task engagement, and task-related motivation and then checked 80 simulated scripts with inserted error ratios ranging from 26% to 38%. Motivation and task engagement were assessed at the beginning of the task, the midpoint of the task, and after the task was over. Performance was measured in terms of sensitivity (error detections) and specificity (false alarm responses). Results indicated that motivation was correlated with higher sensitivity, while self-regulation was correlated with lower specificity. Higher mid-task motivation and higher self-regulation were also predictive of greater task engagement at the midpoint of the task only. Results are discussed and future research directions are proposed.

  16. 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…

  17. Vision and task assistance using modular wireless in vivo surgical robots.

    Science.gov (United States)

    Platt, Stephen R; Hawks, Jeff A; Rentschler, Mark E

    2009-06-01

    Minimally invasive abdominal surgery (laparoscopy) results in superior patient outcomes compared to conventional open surgery. However, the difficulty of manipulating traditional laparoscopic tools from outside the body of the patient generally limits these benefits to patients undergoing relatively low complexity procedures. The use of tools that fit entirely inside the peritoneal cavity represents a novel approach to laparoscopic surgery. Our previous work demonstrated that miniature mobile and fixed-based in vivo robots using tethers for power and data transmission can successfully operate within the abdominal cavity. This paper describes the development of a modular wireless mobile platform for in vivo sensing and manipulation applications. Design details and results of ex vivo and in vivo tests of robots with biopsy grasper, staple/clamp, video, and physiological sensor payloads are presented. These types of self-contained surgical devices are significantly more transportable and lower in cost than current robotic surgical assistants. They could ultimately be carried and deployed by nonmedical personnel at the site of an injury to allow a remotely located surgeon to provide critical first response medical intervention irrespective of the location of the patient.

  18. Learners Performing Tasks in a Japanese EFL Classroom: A Multimodal and Interpersonal Approach to Analysis

    Science.gov (United States)

    Stone, Paul

    2012-01-01

    In this paper I describe and analyse learner task-based interactions from a multimodal perspective with the aim of better understanding how learners' interpersonal relationships might affect task performance. Task-based pedagogy is focused on classroom interaction between learners, yet analysis of tasks has often neglected the analysis of this…

  19. Young L2 learners' performance on a novel morpheme task.

    Science.gov (United States)

    Kohnert, Kathryn; Danahy, Kerry

    2007-07-01

    The teaching of an invented language rule has been proposed as a possible non-biased, language-independent assessment technique useful in differentiating young L2 learners with specific language impairment from their typically developing peers. The current study explores these notions by testing typically developing sequential bilingual children's ability to learn an invented language rule in either L1 (Spanish) or L2 (English). Participants were 20 children, age 3:6-5:8, who attended a Head Start programme. For all children, Spanish was the primary language spoken in the home and English was the primary language of instruction. Children were randomly assigned two groups. Group L1 was taught the novel language rule in Spanish; Group L2 was taught the novel language rule in English. Performance was better for the L1 group than for the L2 group. Moreover, not all of these typical language learners were able to learn the new rule, even in their strongest language. These findings suggest that even for typically developing children, specific language proficiency as well as individual differences are closely linked to performance on this novel morpheme learning task.

  20. Transformation of OODT CAS to Perform Larger Tasks

    Science.gov (United States)

    Mattmann, Chris; Freeborn, Dana; Crichton, Daniel; Hughes, John; Ramirez, Paul; Hardman, Sean; Woollard, David; Kelly, Sean

    2008-01-01

    A computer program denoted OODT CAS has been transformed to enable performance of larger tasks that involve greatly increased data volumes and increasingly intensive processing of data on heterogeneous, geographically dispersed computers. Prior to the transformation, OODT CAS (also alternatively denoted, simply, 'CAS') [wherein 'OODT' signifies 'Object-Oriented Data Technology' and 'CAS' signifies 'Catalog and Archive Service'] was a proven software component used to manage scientific data from spaceflight missions. In the transformation, CAS was split into two separate components representing its canonical capabilities: file management and workflow management. In addition, CAS was augmented by addition of a resource-management component. This third component enables CAS to manage heterogeneous computing by use of diverse resources, including high-performance clusters of computers, commodity computing hardware, and grid computing infrastructures. CAS is now more easily maintainable, evolvable, and reusable. These components can be used separately or, taking advantage of synergies, can be used together. Other elements of the transformation included addition of a separate Web presentation layer that supports distribution of data products via Really Simple Syndication (RSS) feeds, and provision for full Resource Description Framework (RDF) exports of metadata.

  1. Rate of learning and asymptotic performance in an automatization task and the relation to reading.

    Science.gov (United States)

    Hecht, Rozalia; Crewther, David; Crewther, Sheila

    2004-12-01

    In the present study, direct evidence was sought linking cognitive automatic processing with reading in the general adult population. Reading speed on single-task performance and dual-task performance were compared. A total of 18 adults without dyslexia participated (7 men and 11 women, age M=25.3 yr., SD=2.7). Participants initially were trained in single-task mode on two types of tasks. The first was a central alphanumeric equation task (true or false), which comprised 3 subtests of increasing difficulty, ranging from an easily automated task to a varied and unpredictable mathematical operation. The second task was a peripheral pattern subitization task for which stimulus exposure time was related to performance. Finally, participants received dual-task training, which required simultaneous processing of both tasks. Slower reading speed was significantly related to rate of learning and speed of performance on predictable alphanumeric operations in dual-task conditions. There was no effect of reading speed on performance in the varied alphanumeric task. Faster readers were no better than slower readers on the pattern-subitization task. These findings suggest that faster readers automatized the predictable alphanumeric task more rapidly than slower readers and hence were better able to cope with the dual-task condition.

  2. Cardiac data increase association between self-report and both expert ratings of task load and task performance in flight simulator tasks: An exploratory study.

    Science.gov (United States)

    Lehrer, Paul; Karavidas, Maria; Lu, Shou-En; Vaschillo, Evgeny; Vaschillo, Bronya; Cheng, Andrew

    2010-05-01

    Seven professional airplane pilots participated in a one-session test in a Boeing 737-800 simulator. Mental workload for 18 flight tasks was rated by experienced test pilots (hereinafter called "expert ratings") and by study participants' self-report on NASA's Task Load Index (TLX) scale. Pilot performance was rated by a check pilot. The standard deviation of R-R intervals (SDNN) significantly added 3.7% improvement over the TLX in distinguishing high from moderate-load tasks and 2.3% improvement in distinguishing high from combined moderate and low-load tasks. Minimum RRI in the task significantly discriminated high- from medium- and low-load tasks, but did not add significant predictive variance to the TLX. The low-frequency/high-frequency (LF:HF) RRI ratio based on spectral analysis of R-R intervals, and ventricular relaxation time were each negatively related to pilot performance ratings independently of TLX values, while minimum and average RRI were positively related, showing added contribution of these cardiac measures for predicting performance. Cardiac results were not affected by controlling either for respiration rate or motor activity assessed by accelerometry. The results suggest that cardiac assessment can be a useful addition to self-report measures for determining flight task mental workload and risk for performance decrements. Replication on a larger sample is needed to confirm and extend the results. Copyright 2010 Elsevier B.V. All rights reserved.

  3. Virtual reality robotic surgery warm-up improves task performance in a dry laboratory environment: a prospective randomized controlled study.

    Science.gov (United States)

    Lendvay, Thomas S; Brand, Timothy C; White, Lee; Kowalewski, Timothy; Jonnadula, Saikiran; Mercer, Laina D; Khorsand, Derek; Andros, Justin; Hannaford, Blake; Satava, Richard M

    2013-06-01

    Preoperative simulation warm-up has been shown to improve performance and reduce errors in novice and experienced surgeons, yet existing studies have only investigated conventional laparoscopy. We hypothesized that a brief virtual reality (VR) robotic warm-up would enhance robotic task performance and reduce errors. In a 2-center randomized trial, 51 residents and experienced minimally invasive surgery faculty in General Surgery, Urology, and Gynecology underwent a validated robotic surgery proficiency curriculum on a VR robotic simulator and on the da Vinci surgical robot (Intuitive Surgical Inc). Once they successfully achieved performance benchmarks, surgeons were randomized to either receive a 3- to 5-minute VR simulator warm-up or read a leisure book for 10 minutes before performing similar and dissimilar (intracorporeal suturing) robotic surgery tasks. The primary outcomes compared were task time, tool path length, economy of motion, technical, and cognitive errors. Task time (-29.29 seconds, p = 0.001; 95% CI, -47.03 to -11.56), path length (-79.87 mm; p = 0.014; 95% CI, -144.48 to -15.25), and cognitive errors were reduced in the warm-up group compared with the control group for similar tasks. Global technical errors in intracorporeal suturing (0.32; p = 0.020; 95% CI, 0.06-0.59) were reduced after the dissimilar VR task. When surgeons were stratified by earlier robotic and laparoscopic clinical experience, the more experienced surgeons (n = 17) demonstrated significant improvements from warm-up in task time (-53.5 seconds; p = 0.001; 95% CI, -83.9 to -23.0) and economy of motion (0.63 mm/s; p = 0.007; 95% CI, 0.18-1.09), and improvement in these metrics was not statistically significantly appreciated in the less-experienced cohort (n = 34). We observed significant performance improvement and error reduction rates among surgeons of varying experience after VR warm-up for basic robotic surgery tasks. In addition, the VR warm-up reduced errors on

  4. 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…

  5. Training or non-surgical factors-what determines a good surgical performance? A randomised controlled trial.

    Science.gov (United States)

    Lindlohr, Cornelia; Lefering, R; Saad, S; Heiss, M M; Pape-Köhler, C

    2017-06-01

    Acquiring laparoscopic skills is a necessity for every young surgeon. Whether it is a talent or a non-surgical skill that determines the surgical performance of an endoscopic operation has been discussed for years. In other disciplines aptitude testing has become the norm. Airlines, for example, have implemented assessments to test the natural aptitude of future pilots to predict their performance later on. In the medical field, especially surgery, there are no similar comparable tests implemented or even available. This study investigates the influence of potential factors that may predict the successful performance of a complex laparoscopic operation, such as the surgeon's age, gender or learning method. This study focussed 70 surgical trainees. It was designed as a secondary analysis of data derived from a 2 × 2 factorial randomised controlled trial of practical training and/or multimedia training (four groups) in an experimental exercise. Both before and then after the training sessions, the participating trainees performed a laparoscopic cholecystectomy in a pelvitrainer. Surgical performance was then evaluated using a modified objective structured assessment of technical skills (OSATS). Participants were classified as 'Skilled' (high score in the pre-test), 'Good Learner' (increase from pre- to post-test) or 'Others' based on the OSATS results. Based on the results of the recorded performance, the training methods as well as non-surgical skills were eventually evaluated in a univariate and in a multivariate analysis. In the pre-training performance 11 candidates were categorised as 'Skilled' (15.7%), 35 participants as 'Good Learners' (50.0%) and 24 participants were classified as 'Others'. The univariate analysis showed that the age, a residency in visceral surgery, and participation in a multimedia training were significantly associated with this grouping. Multivariate analyses revealed that residency in visceral surgery was the most predictive factor

  6. 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 inducti

  7. Working memory capacity predicts conflict-task performance

    NARCIS (Netherlands)

    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 co

  8. The significance of task significance: Job performance effects, relational mechanisms, and boundary conditions.

    Science.gov (United States)

    Grant, Adam M

    2008-01-01

    Does task significance increase job performance? Correlational designs and confounded manipulations have prevented researchers from assessing the causal impact of task significance on job performance. To address this gap, 3 field experiments examined the performance effects, relational mechanisms, and boundary conditions of task significance. In Experiment 1, fundraising callers who received a task significance intervention increased their levels of job performance relative to callers in 2 other conditions and to their own prior performance. In Experiment 2, task significance increased the job dedication and helping behavior of lifeguards, and these effects were mediated by increases in perceptions of social impact and social worth. In Experiment 3, conscientiousness and prosocial values moderated the effects of task significance on the performance of new fundraising callers. The results provide fresh insights into the effects, relational mechanisms, and boundary conditions of task significance, offering noteworthy implications for theory, research, and practice on job design, social information processing, and work motivation and performance.

  9. 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.

  10. Use of Performance Measures to Evaluate, Document Competence and Deterioration of ASSET Surgical Skills

    Science.gov (United States)

    2016-05-01

    fielding of data collection tool. 15. SUBJECT TERMS Performance evaluation, ASSET, vascular trauma , surgical training, medical education 16...33 Appendix 9: Management of Vascular Trauma by Senior Surgical Residents: Perception Does Not Equal Reality...69 Appendix 30: Perception Does Not Equal Reality for Resident Vascular Trauma

  11. 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.

  12. The Effect of Task Repetition on Fluency and Accuracy of EFL Saudi Female Learners' Oral Performance

    Science.gov (United States)

    Gashan, Amani K.; Almohaisen, Fahad M.

    2014-01-01

    This study aimed to examine the effect of task repetition on foreign language output. Twenty eight Saudi female students in the Preparatory Year (PY) at King Saud university, were randomly selected to conduct an oral information-gap task. The participants were asked to perform the task two times with two-week interval between the two performances.…

  13. 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…

  14. 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…

  15. A framework for the recognition of high-level surgical tasks from video images for cataract surgeries.

    Science.gov (United States)

    Lalys, F; Riffaud, L; Bouget, D; Jannin, P

    2012-04-01

    The need for a better integration of the new generation of computer-assisted-surgical systems has been recently emphasized. One necessity to achieve this objective is to retrieve data from the operating room (OR) with different sensors, then to derive models from these data. Recently, the use of videos from cameras in the OR has demonstrated its efficiency. In this paper, we propose a framework to assist in the development of systems for the automatic recognition of high-level surgical tasks using microscope videos analysis. We validated its use on cataract procedures. The idea is to combine state-of-the-art computer vision techniques with time series analysis. The first step of the framework consisted in the definition of several visual cues for extracting semantic information, therefore, characterizing each frame of the video. Five different pieces of image-based classifiers were, therefore, implemented. A step of pupil segmentation was also applied for dedicated visual cue detection. Time series classification algorithms were then applied to model time-varying data. Dynamic time warping and hidden Markov models were tested. This association combined the advantages of all methods for better understanding of the problem. The framework was finally validated through various studies. Six binary visual cues were chosen along with 12 phases to detect, obtaining accuracies of 94%.

  16. Enhancing Surgical Team Performance with Game-Based training

    Directory of Open Access Journals (Sweden)

    Christine Kreutzer

    2016-03-01

    Full Text Available  Poor team communication has been attributed to many patient safety issues in healthcare. Efficacious team training methods are needed. The present study examines the use of a game-based training approach for enhancing surgical team communication skills. Participants who played the game achieved improved declarative knowledge, and had greater levels of training transfer relative to the control group. These results suggest that game-based training may to be a promising mechanism for improving teamwork in the healthcare industry.  

  17. THE EFFECTS OF TASK INTERDEPENDENCE, TEAM COOPERATION, AND TEAM CONFLICT ON JOB PERFORMANCE

    National Research Council Canada - National Science Library

    Chun-Chang Lee; Yu-Hsin Lin; Hsin-Chung Huang; Wei-Wen Huang; Hsu-Hung Teng

    2015-01-01

      Using a linear structural model, we investigated the impact of task interdependence, task and relationship conflict in a team, and team cooperation on job performance of real estate brokers in Kaohsiung, Taiwan...

  18. Multitasking and aging: do older adults benefit from performing a highly practiced task?

    Science.gov (United States)

    Allen, Philip A; Lien, Mei-Ching; Ruthruff, Eric; Voss, Andreas

    2014-01-01

    BACKGROUND/STUDY CONTEXT: The present study examined the effect of training on age differences in performing a highly practiced task using the psychological refractory period (PRP) paradigm (Pashler, 1984, Journal of Experimental Psychology: Human Perception and Performance, 10, 358-377). Earlier training studies have concentrated on tasks that are not already overlearned. The present question of interest is whether task dual-task integration will be more efficient when single-task performance is approaching asymptotic levels. Task 1 was red/green signal discrimination (green = "go" and red = "wait"; analogous to pedestrian signals) and Task 2 was tone discrimination (white noise vs. a horn "honk"; analogous to traffic sound). The stimulus onset asynchrony (SOA) between Task 1 and Task 2 was varied (50, 150, 600, and 1000 ms). All individuals participated in eight sessions spread over 8 weeks (one session per week). Participants completed a dual-task pretest (Week 1), followed by 6 weeks of single-task testing (Weeks 2-7), followed by a dual-task posttest (Week 8). Although older adults showed larger overall dual-task costs (i.e., PRP effects), they were able to reduce the costs with practice as much as younger adults. However, even when training on Task 1 results in asymptotic performance, this still did not lead to an appreciable reduction in dual-task costs. Also, older adults, but not younger adults, responded more rapidly to green stimuli than to red stimuli in the Task 1 training latency data. The authors confirmed this green/go bias using diffusion modeling, which takes into account response time and error rates at the same time. This green/go bias is potentially dangerous at crosswalks, especially when combined with large dual-task interference, and might contribute to the high rate of crosswalk accidents in the elderly.

  19. Impaired Object Handling during Bimanual Task Performance in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Stacey L. Gorniak

    2014-01-01

    Full Text Available We investigated the kinetic features of manual dexterity and fine motor control during a task that resembles an activity of daily living in 30 persons with relapsing-remitting multiple sclerosis (PwMS. Specifically, a novel two-transducer system was used to measure time and grip-load forces during a bimanual task that is similar to opening and closing a jar. We hypothesized that PwMS would have increased grip force production, deteriorations in kinetic timing, and preserved grip-load coupling indices compared to healthy controls (i.e., young and older adults. Increased grip force production and deterioration in timing indices were confirmed in PwMS. Abnormal grip-load coupling was exhibited by PwMS, in contrast to healthy participants. The correlation between task time and self-reported disability scores suggests that objective measurement of impaired upper-extremity movements relates to perception of overall function.

  20. Task scheduling for high performance low power embedded computing

    Science.gov (United States)

    Deniziak, Stanislaw; Dzitkowski, Albert

    2016-12-01

    In this paper we present a method of task scheduling for low-power real-time embedded systems. We assume that the system is specified as a task graph, then it is implemented using multi-core embedded processor with low-power processing capabilities. We propose a new scheduling method to create the optimal schedule. The goal of optimization is to minimize the power consumption while all time constraints will be satisfied. We present experimental results, obtained for some standard benchmarks, showing advantages of our method.

  1. On the link between mind wandering and task performance over time.

    Science.gov (United States)

    Thomson, David R; Seli, Paul; Besner, Derek; Smilek, Daniel

    2014-07-01

    Here we test the hypothesis that fluctuations in subjective reports of mind wandering over time-on-task are associated with fluctuations in performance over time-on-task. In Study 1, we employed a singleton search task and found that performance did not differ prior to on- and off-task reports, nor did individual differences in mind wandering predict differences in performance (so-called standard analytic methods). Importantly however, we find that fluctuations in mind wandering over time are strongly associated with fluctuations in behavior. In Study 2, we provide a replication of the relation between mind wandering and performance over time found in Study 1, using a Flanker interference task. These data indicate (1) a tight coupling between mind wandering and performance over time and (2) that a temporal-analytic approach can reveal effects of mind wandering on performance in tasks where standard analyses fail to do so. The theoretical and methodological implications of these findings are discussed.

  2. Differences in dual-task performance and prefrontal cortex activation between younger and older adults

    Directory of Open Access Journals (Sweden)

    Ohsugi Hironori

    2013-01-01

    Full Text Available Abstract Background The purpose of this study was to examine task-related changes in prefrontal cortex (PFC activity during a dual-task in both healthy young and older adults and compare patterns of activation between the age groups. We also sought to determine whether brain activation during a dual-task relates to executive/attentional function and how measured factors associated with both of these functions vary between older and younger adults. Results Thirty-five healthy volunteers (20 young and 15 elderly participated in this study. Near-infrared spectroscopy (NIRS was employed to measure PFC activation during a single-task (performing calculations or stepping and dual-task (performing both single-tasks at once. Cognitive function was assessed in the older patients with the Trail-making test part B (TMT-B. Major outcomes were task performance, brain activation during task (oxygenated haemoglobin: Oxy-Hb measured by NIRS, and TMT-B score. Mixed ANOVAs were used to compare task factors and age groups in task performance. Mixed ANOVAs also compared task factors, age group and time factors in task-induced changes in measured Oxy-Hb. Among the older participants, correlations between the TMT-B score and Oxy-Hb values measured in each single-task and in the dual-task were examined using a Pearson correlation coefficient. Oxy-Hb values were significantly increased in both the calculation task and the dual-task within patients in both age groups. However, the Oxy-Hb values associated with there were higher in the older group during the post-task period for the dual-task. Also, there were significant negative correlations between both task-performance accuracy and Oxy-Hb values during the dual-task and participant TMT-B scores. Conclusions Older adults demonstrated age-specific PFC activation in response to dual-task challenge. There was also a significant negative correlation between PFC activation during dual-task and executive

  3. 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…

  4. Conjunctive Continuous Performance Task (CCPT)--A Pure Measure of Sustained Attention

    Science.gov (United States)

    Shalev, Lilach; Ben-Simon, Anat; Mevorach, Carmel; Cohen, Yoav; Tsal, Yehoshua

    2011-01-01

    Among the large variety of attentional tasks that have been used to study sustained attention, the Continuous Performance Task (CPT) is perhaps the most widely used. Despite substantial differences in task characteristics and demands, all CPT paradigms have been referred to as measures of sustained attention. In the present study we introduce a…

  5. Group Motivation and Group Task Performance: The Expectancy-Valence Theory Approach.

    Science.gov (United States)

    Nakanishi, Masayuki

    1988-01-01

    Investigated effects of group motivation on group task performance. Created two levels of valence, expectancy and instrumentality. Valence variable reflected on group productivity on unstructured and task persistence measures. Expectancy variable's effect was on task persistence measure. Instrumentality affected group productivity on structured…

  6. Extending the body to virtual tools using a robotic surgical interface: evidence from the crossmodal congruency task.

    Directory of Open Access Journals (Sweden)

    Ali Sengül

    Full Text Available The effects of real-world tool use on body or space representations are relatively well established in cognitive neuroscience. Several studies have shown, for example, that active tool use results in a facilitated integration of multisensory information in peripersonal space, i.e. the space directly surrounding the body. However, it remains unknown to what extent similar mechanisms apply to the use of virtual-robotic tools, such as those used in the field of surgical robotics, in which a surgeon may use bimanual haptic interfaces to control a surgery robot at a remote location. This paper presents two experiments in which participants used a haptic handle, originally designed for a commercial surgery robot, to control a virtual tool. The integration of multisensory information related to the virtual-robotic tool was assessed by means of the crossmodal congruency task, in which subjects responded to tactile vibrations applied to their fingers while ignoring visual distractors superimposed on the tip of the virtual-robotic tool. Our results show that active virtual-robotic tool use changes the spatial modulation of the crossmodal congruency effects, comparable to changes in the representation of peripersonal space observed during real-world tool use. Moreover, when the virtual-robotic tools were held in a crossed position, the visual distractors interfered strongly with tactile stimuli that was connected with the hand via the tool, reflecting a remapping of peripersonal space. Such remapping was not only observed when the virtual-robotic tools were actively used (Experiment 1, but also when passively held the tools (Experiment 2. The present study extends earlier findings on the extension of peripersonal space from physical and pointing tools to virtual-robotic tools using techniques from haptics and virtual reality. We discuss our data with respect to learning and human factors in the field of surgical robotics and discuss the use of new

  7. An Analysis of Tasks Performed in the Ornamental Horticulture Industry.

    Science.gov (United States)

    Berkey, Arthur L.; Drake, William E.

    This publication is the result of a detailed task analysis study of the ornamental horticulture industry in New York State. Nine types of horticulture businesses identified were: (1) retail florists, (2) farm and garden supply store, (3) landscape services, (4) greenhouse production, (5) nursery production, (6) turf production, (7) arborist…

  8. Performance of Healthy Participants on the Iowa Gambling Task

    Science.gov (United States)

    Steingroever, Helen; Wetzels, Ruud; Horstmann, Annette; Neumann, Jane; Wagenmakers, Eric-Jan

    2013-01-01

    The Iowa Gambling Task (IGT; Bechara, Damasio, Damasio, & Anderson, 1994) is often used to assess decision-making deficits in clinical populations. The interpretation of the results hinges on 3 key assumptions: (a) healthy participants learn to prefer the good options over the bad options; (b) healthy participants show homogeneous choice behavior;…

  9. Task Dissociation in Prospective Memory Performance in Individuals With ADHD

    NARCIS (Netherlands)

    Altgassen, A.M.; Kretschmer, A.; Kliegel, M.

    2014-01-01

    OBJECTIVE: The present study investigated, for the first time, event- and time-based prospective memory (PM) in the same sample of adults with ADHD within one paradigm using parallel task constraints. METHOD: A total of 25 individuals with ADHD and 25 matched neurotypical controls completed a comput

  10. The Relationship between Bilingualism and the Performance of Spatial Tasks

    Science.gov (United States)

    McLeay, Heather

    2003-01-01

    The well-documented evidence that bilinguals demonstrate cognitive advantages over monolinguals is used as a foundation for the hypothesis that bilinguals will be better able to solve certain spatial tasks, and a theoretical framework for this hypothesis is constructed. The paper describes an experiment to explore this hypothesis. A series of…

  11. Effect of Posthypnotic Dissociation on the Performance of Interfering Tasks

    Science.gov (United States)

    Stevenson, James H.

    1976-01-01

    Builds upon earlier experiments in an attempt to measure the interferences between simultaneous tasks and the effects of hypnotic dissociation in increasing or decreasing this interference, thus testing the validity of one or the other of two theoretical models. (Author/RK)

  12. 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.

  13. Live-social-video reward maintains joystick task performance in bonnet macaques.

    Science.gov (United States)

    Andrews, M W; Rosenblum, L A

    1993-12-01

    A number of studies have now indicated that monkeys of several species will perform hundreds of food-rewarded joystick tasks on a daily basis. Our goal in this study was to identify the level of joystick task performance that could be maintained by 10 sec. of live, color video of a conspecific social group contingent upon the completion of a joystick task. The subjects were five individually housed bonnet macaques that were highly experienced on joystick tasks. Performance with social-video reward was compared to that maintained by a 190-mg banana-flavored pellet reward and to a nonreward condition. Comparable levels of task activity were maintained by both video and pellet reward, whereas task activity nearly ceased in the absence of reward. Four of the five monkeys increased their levels of task activity between the first and second weeks of social-video reward.

  14. 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 p

  15. 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.

  16. 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.

  17. 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...

  18. The effect of a performance-based intra-procedural checklist on a simulated emergency laparoscopic task in novice surgeons.

    Science.gov (United States)

    El Boghdady, Michael; Tang, Benjie; Alijani, Afshin

    2016-09-01

    Surgical checklists are in use as means to reduce errors. Checklists are infrequently applied during emergency situations in surgery. We aimed to study the effect of a simple self-administered performance-based checklist on the laparoscopic task when applied during an emergency-simulated scenario. The aviation checklist for unexpected situations is commonly used for simulated training of pilots to handle emergency during flights. This checklist was adopted for use as a standardised-performance-based checklist during emergency surgical tasks. Thirty consented laparoscopic novices were exposed unexpectedly to a bleeding vessel in a laparoscopic virtual reality simulator as an emergency scenario. The task consisted of using laparoscopic clips to achieve haemostasis. Subjects were randomly allocated into two equal groups; those using the checklist that was applied once every 20 s (checklist group) and those without (control group). The checklist group performed significantly better in 5 out of 7 technical factors when compared to the control group: right instrument path length (m), median (IQR) 1.44 [1.22] versus 2.06 [1.70] (p = 0.029), right instrument angular path (degree) 312.10 (269.44 versus 541.80 [455.16] (p = 0.014), left instrument path length (m) 1.20 [0.60] versus 2.08 [2.02] (p = 0.004), and left instrument angular path (degree) 277.62 [132.11] versus 385.88 [428.42] (p = 0.017). The checklist group committed significantly fewer number of errors in the application of haemostatic clips, 3 versus 28 (p = 0.006). Although statistically not significant, total blood loss (lit) decreased in the checklist group from 0.83 [1.23] to 0.78 [0.28] (p = 0.724) and total time (sec) from 186.51 [145.69] to 125.14 [101.46] (p = 0.165). The performance-based intra-procedural checklist significantly enhanced the surgical task performance of novices in an emergency-simulated scenario.

  19. 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…

  20. Argumentative and narrative written task performance: Differential effects of critical thinking

    OpenAIRE

    Azizollah DABAGHI; Zabihi, Reza; Rezazadeh, Mohsen

    2013-01-01

    This study compares the differential role of critical thinking in learners’ performance on argumentative and narrative written tasks. The study involved the measurement of 70 upper-intermediate learners’ critical thinking using the Watson-Glaser Critical Thinking Appraisal (WGCTA) as well as the elicitation of their performance on the written narrative and argumentative tasks. While the argumentative task required that learners write an argumentative essay giving their opinions concerning the...

  1. Investigating graphesthesia task performance in the biological relatives of schizophrenia patients.

    Science.gov (United States)

    Chang, Bernard P; Lenzenweger, Mark F

    2004-01-01

    This study compared the performance of 39 biological relatives of persons with schizophrenia to that of 30 normal adult controls on graphesthesia processing, a complex somatosensory processing task. The relatives performed significantly worse on the graphesthesia task compared to the healthy controls. The relatives and control subjects, however, did not differ on two neurocognitive control tasks. These data are interpreted within the context of a somatosensory deficit linked to schizophrenia liability.

  2. 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.

  3. Performance on a virtual reality angled laparoscope task correlates with spatial ability of trainees.

    Science.gov (United States)

    Rosenthal, Rachel; Hamel, Christian; Oertli, Daniel; Demartines, Nicolas; Gantert, Walter A

    2010-08-01

    The aim of the present study was to investigate whether trainees' performance on a virtual reality angled laparoscope navigation task correlates with scores obtained on a validated conventional test of spatial ability. 56 participants of a surgery workshop performed an angled laparoscope navigation task on the Xitact LS 500 virtual reality Simulator. Performance parameters were correlated with the score of a validated paper-and-pencil test of spatial ability. Performance at the conventional spatial ability test significantly correlated with performance at the virtual reality task for overall task score (p travel speed (p = 0.947). In conclusion, trainees' performance in a standardized virtual reality camera navigation task correlates with their innate spatial ability. This VR session holds potential to serve as an assessment tool for trainees.

  4. Do we perform surgical programming well? How can we improve it?

    Science.gov (United States)

    Albareda, J; Clavel, D; Mahulea, C; Blanco, N; Ezquerra, L; Gómez, J; Silva, J M

    2017-09-07

    The objective is to establish the duration of our interventions, intermediate times and surgical performance. This will create a virtual waiting list to apply a mathematical programme that performs programming with maximum performance. Retrospective review of 49 surgical sessions obtaining the delay in start time, intermediate time and surgical performance. Retrospective review of 4,045 interventions performed in the last 3 years to obtain the average duration of each type of surgery. Creation of a virtual waiting list of 700 patients in order to perform virtual programming through the MIQCP-P until achieving optimal performance. Our surgical performance with manual programming was 75.9%, ending 22.4% later than 3pm. The performance in the days without suspensions was 78.4%. The delay at start time was 9.7min. The optimum performance was 77.5% with a confidence of finishing before 15h of 80.6%. The waiting list has been scheduled in 254 sessions. Our manual surgical performance without suspensions (78.4%) was superior to the optimal (77.5%), generating days finished later than 3pm and suspensions. The possibilities for improvement are to achieve punctuality at the start time and adjust the schedule to the ideal performance. The virtual programming has allowed us to obtain our ideal performance and to establish the number of operating rooms necessary to solve the waiting list created. The data obtained in virtual mathematical programming are reliable enough to implement this model with guarantees. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Development and Validation of an Admission Test Designed to Assess Samples of Performance on Academic Tasks

    Science.gov (United States)

    Tanilon, Jenny; Segers, Mien; Vedder, Paul; Tillema, Harm

    2009-01-01

    This study illustrates the development and validation of an admission test, labeled as Performance Samples on Academic Tasks in Educational Sciences (PSAT-Ed), designed to assess samples of performance on academic tasks characteristic of those that would eventually be encountered by examinees in an Educational Sciences program. The test was based…

  6. 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…

  7. Task complexity and linguistic performance in L2 writing and speaking: the effect of mode

    NARCIS (Netherlands)

    Kuiken, F.; Vedder, I.; Robinson, P.

    2011-01-01

    The chapter discusses the question to what extent the effect of task complexity on linguistic performance in L2 writing and speaking is influenced by the mode in which the tasks have to be performed (oral versus written). The majority of studies which have been conducted so far in the framework of

  8. 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)

  9. Effects of transportation noise and attitudes on noise annoyance and task performance

    NARCIS (Netherlands)

    White, K.; Meeter, M.; Bronkhorst, A.

    2012-01-01

    In this study, effects on task performance and annoyance by aircraft and road traffic noise and attitudes towards these noise sources were addressed in a lab-setting. On day 1 of the study, participants performed a 3-back working memory task in silence and with noise samples played over a headphone

  10. Cross-Lagged Relations between Task Motivation and Performance in Arithmetic and Literacy in Kindergarten

    Science.gov (United States)

    Viljaranta, Jaana; Lerkkanen, Marja-Kristiina; Poikkeus, Anna-Maija; Aunola, Kaisa; Nurmi, Jari-Erik

    2009-01-01

    To examine the cross-lagged relationships between children's task motivation in mathematics and literacy, and their related performance, 139 children aged 5-6 years were examined twice during their kindergarten year. The results showed that only math-related task motivation and arithmetic performance showed cross-lagged relationship: the higher…

  11. The effect of caffeine on cognitive task performance and motor fatigue

    NARCIS (Netherlands)

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

    2005-01-01

    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 a

  12. Task Performance Using the Library and Internet To Acquire Business Intelligence.

    Science.gov (United States)

    Christensen, Edward W.; Bailey, James R.

    1998-01-01

    Describes a study that compared performance differences (perceived, actual, and temporal) for a strategic business information acquisition experimental task when subjects used a library versus using the Internet. It was found that task performance decreased and time to completion increased when using the Internet. (Author/LRW)

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    pollution levels created by placing or removing a pollution source (i.e. a used carpet) behind a screen. During the exposure, the subjects performed four different office tasks presented on a computer monitor. The tasks were performed at two paces: normal and maximum. When the pollution source was present...

  14. Working memory and acquisition of implicit knowledge by imagery training, without actual task performance.

    Science.gov (United States)

    Helene, A F; Xavier, G F

    2006-04-28

    This study investigated acquisition of a mirror-reading skill via imagery training, without the actual performance of a mirror-reading task. In experiment I, healthy volunteers simulated writing on an imaginary, transparent screen placed at eye level, which could be read by an experimenter facing the subject. Performance of this irrelevant motor task required the subject to imagine the letters inverted, as if seen in a mirror from their own point of view (imagery training). A second group performed the same imagery training interspersed with a complex, secondary spelling and counting task. A third, control, group simply wrote the words as they would normally appear from their own point of view. After training with 300 words, all subjects were tested in a mirror-reading task using 60 non-words, constructed according to acceptable letter combinations of the Portuguese language. Compared with control subjects, those exposed to imagery training, including those who switched between imagery and the complex task, exhibited shorter reading times in the mirror-reading task. Experiment II employed a 2 x 3 design, including two training conditions (imagery and actual mirror-reading) and three competing task conditions (a spelling and counting switching task, a visual working memory concurrent task, and no concurrent task). Training sessions were interspersed with mirror-reading testing sessions for non-words, allowing evaluation of the mirror-reading acquisition process during training. The subjects exposed to imagery training acquired the mirror-reading skill as quickly as those exposed to the actual mirror-reading task. Further, performance of concurrent tasks together with actual mirror-reading training severely disrupted mirror-reading skill acquisition; this interference effect was not seen in subjects exposed to imagery training and performance of the switching and the concurrent tasks. These results unequivocally show that acquisition of implicit skills by top

  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 (p< 0.02) of hypoxia. Furthermore, in EEG, there was a significant decrease in mid-level beta (15.19-18.37Hz) during the hypoxic condition in thirteen of sixteen sites across the scalp. Task 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

  16. Examination of the Role of Expectancies on Task Performance in College Students Concerned about ADHD.

    Science.gov (United States)

    Wei, Christina; Suhr, Julie A

    2015-01-01

    Prior research has shown that performance on cognitive tasks can be influenced by expectations (Smith & Sullivan, 2003 ; Suhr & Gunstad, 2002 , 2005 ). The current study examined whether cuing a belief about the diagnostic saliency of a cognitive task among young adults who expressed concern about having attention-deficit hyperactivity disorder (ADHD) influenced task performance. Participants were randomly assigned to either receive neutral directions or be cued to a belief that the task had diagnostic saliency prior to completing a working-memory task. Supporting our hypothesis, college students with higher prestudy report of ADHD symptoms who were cued with a belief about the diagnostic saliency of the task performed worse compared with students who received neutral instructions. As many researchers and clinicians currently rely exclusively on self-reported symptoms and neuropsychological tests to diagnose ADHD, our findings highlight the importance of comprehensive assessment for provision of appropriate clinical services to adults presenting with ADHD concerns.

  17. Lateralized increases in cerebral blood flow during performance of verbal and spatial tasks: relationship with performance level.

    Science.gov (United States)

    Gur, R C; Ragland, J D; Resnick, S M; Skolnick, B E; Jaggi, J; Muenz, L; Gur, R E

    1994-03-01

    Physiologic neuroimaging studies have shown lateralized regional increase in brain activity during cognitive tasks, but the hypothesis that such changes are correlated with task performance has not been tested directly. We examined cerebral blood flow (CBF) changes induced by cognitive tasks in relation to performance. CBF was measured with the 133Xenon clearance method in 34 normal right-handed young (age verbal analogies and a spatial line orientation test. Performance measures included "speed" and "power" estimates of both activation tasks. Resting CBF was moderately correlated with performance. The correlations were slightly higher with activated CBF for verbal but not spatial performance. The degree of increase (task-baseline) did not correlate with performance for either task. The highest and topographically specific correlations were obtained between laterality of CBF and verbal performance. Higher left hemispheric activation was correlated with verbal performance, and this correlation was significantly higher in the angular gyrus region. For the spatial task the correlations were with relatively higher right hemispheric activation but without regional specificity. The results underscore the importance of integrating behavioral performance data with physiologic measures in neuroimaging activation studies.

  18. Effects of an indoor plant on creative task performance and mood.

    Science.gov (United States)

    Shibata, Seiji; Suzuki, Naoto

    2004-11-01

    In this study, we investigated the effect of an indoor plant on task performance and on mood. Three room arrangements were used as independent variables: a room with (1) a plant, or (2) a magazine rack with magazines placed in front of the participants, or (3) a room with neither of these objects. Undergraduate students (M= 35, F= 55) performed a task of associating up to 30 words with each of 20 specified words in a room with one of the three room arrangements. Task performance scores showed that female participants performed better in view of the plant in comparison to the magazine rack (p plant or the magazine rack in the room compared to the no object condition (p plant or the magazine rack. It is suggested that the compatibility between task demand and the environment is an important factor in facilitating task performances.

  19. 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.

  20. 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 tea

  1. 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

  2. An action-incongruent secondary task modulates prediction accuracy in experienced performers: evidence for motor simulation.

    Science.gov (United States)

    Mulligan, Desmond; Lohse, Keith R; Hodges, Nicola J

    2016-07-01

    We provide behavioral evidence that the human motor system is involved in the perceptual decision processes of skilled performers, directly linking prediction accuracy to the (in)ability of the motor system to activate in a response-specific way. Experienced and non-experienced dart players were asked to predict, from temporally occluded video sequences, the landing position of a dart thrown previously by themselves (self) or another (other). This prediction task was performed while additionally performing (a) an action-incongruent secondary motor task (right arm force production), (b) a congruent secondary motor task (mimicking) or (c) an attention-matched task (tone-monitoring). Non-experienced dart players were not affected by any of the secondary task manipulations, relative to control conditions, yet prediction accuracy decreased for the experienced players when additionally performing the force-production, motor task. This interference effect was present for 'self' as well as 'other' decisions, reducing the accuracy of experienced participants to a novice level. The mimicking (congruent) secondary task condition did not interfere with (or facilitate) prediction accuracy for either group. We conclude that visual-motor experience moderates the process of decision making, such that a seemingly visual-cognitive prediction task relies on activation of the motor system for experienced performers. This fits with a motor simulation account of action prediction in sports and other tasks, and alerts to the specificity of these simulative processes.

  3. The complexity of the Latin Square task and its influ-ence on children's performance

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; XIN ZiQiang; LIN ChongDe; LI Hong

    2009-01-01

    Prior studies analyzed the complexity of the Latin Square task solely based on the relational complexity theory, which, with the relational complexity defined by the complexity of relations processed in paral-lel, could not fully predict children's performance on the task. So we developed an alternative method to analyze the task complexity by the relational complexity and the necessary processing steps to find a solution. The present study tested the validity of the new method applying to the Latin Square task and investigated how the task complexity influenced children's performance on the task. 195 pupils from Grade 2-5 were recruited to perform computerized Latin Square task of 15 items. The results showed that: (i) The children's performance on the Latin Square task fitted perfectly to the predictions by the Rasch measurement model. The relational complexity and the necessary processing steps both validly predicted the children's reaction time for correct answers and the item difficulty levels assessed by the Rasch analysis. This validated our method for task complexity analysis. (ii) Generally, all the 2nd-5th graders performed well on the items whose relational complexity was binary or ternary. However, they had difficulties in solving the quaternary items, although there was improvement from grade 2 to grade 5.

  4. 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.

  5. The assessment of risky decision making: a factor analysis of performance on the Iowa Gambling Task, Balloon Analogue Risk Task, and Columbia Card Task.

    Science.gov (United States)

    Buelow, Melissa T; Blaine, Amber L

    2015-09-01

    Researchers and clinicians frequently use behavioral measures to assess decision making. The most common task that is marketed to clinicians is the Iowa Gambling Task (IGT), thought to assess risky decision making. How does performance on the IGT relate to performance on other common measures of decision making? The present study sought to examine relationships between the IGT, the Balloon Analogue Risk Task (BART), and the Columbia Card Task (CCT). Participants were 390 undergraduate students who completed the IGT, BART, and either the "hot" or "cold" CCT. Principal components factor analysis on the IGT, BART, and CCT-cold (n = 112) indicated that the IGT measures a different component of decision making than the BART, and the CCT-cold weakly correlated with early IGT trials. Results of the exploratory factor analysis on the IGT, BART, and CCT-hot (n = 108) revealed a similar picture: the IGT and BART assessed different types of decision making, and the BART and CCT-hot were weakly correlated. A confirmatory factor analysis (n = 170) indicated that a 3-factor model without the CCT-cold (Factor 1: later IGT trials; Factor 2: BART; and Factor 3: early IGT trials) was a better fitting model than one that included the CCT-cold and early IGT trials on the same factor. Collectively, the present results suggest that the IGT, BART, and CCT all measure unique, nonoverlapping decision making processes. Further research is needed to more fully understand the neuropsychological construct of decision making.

  6. Delays and user performance in human-computer-network interaction tasks.

    Science.gov (United States)

    Caldwell, Barrett S; Wang, Enlie

    2009-12-01

    This article describes a series of studies conducted to examine factors affecting user perceptions, responses, and tolerance for network-based computer delays affecting distributed human-computer-network interaction (HCNI) tasks. HCNI tasks, even with increasing computing and network bandwidth capabilities, are still affected by human perceptions of delay and appropriate waiting times for information flow latencies. Conducted were 6 laboratory studies with university participants in China (Preliminary Experiments 1 through 3) and the United States (Experiments 4 through 6) to examine users' perceptions of elapsed time, effect of perceived network task performance partners on delay tolerance, and expectations of appropriate delays based on task, situation, and network conditions. Results across the six experiments indicate that users' delay tolerance and estimated delay were affected by multiple task and expectation factors, including task complexity and importance, situation urgency and time availability, file size, and network bandwidth capacity. Results also suggest a range of user strategies for incorporating delay tolerance in task planning and performance. HCNI user experience is influenced by combinations of task requirements, constraints, and understandings of system performance; tolerance is a nonlinear function of time constraint ratios or decay. Appropriate user interface tools providing delay feedback information can help modify user expectations and delay tolerance. These tools are especially valuable when delay conditions exceed a few seconds or when task constraints and system demands are high. Interface designs for HCNI tasks should consider assistant-style presentations of delay feedback, information freshness, and network characteristics. Assistants should also gather awareness of user time constraints.

  7. Effects of mental resource availability on looming task performance.

    Science.gov (United States)

    McGuire, Austen B; Gillath, Omri; Vitevitch, Michael S

    2016-01-01

    Past research has shown that the looming bias-the tendency to judge one's distance to an approaching object as shorter than in actuality-is stronger among people who are physically weak or vulnerable. The current study examined whether the looming bias would also be stronger among people who are mentally weak or vulnerable. We tested that hypothesis by subjecting 46 young adults to cognitive load and examining their perceptions of approaching objects distance. Participants completed two blocks of the looming task, once under high cognitive load (memorizing a seven-digit number) and once under low load (memorizing a two-digit number). Participants exhibited a stronger looming bias under high load than under low load. These findings support the hypothesis that the looming bias will be stronger when people are weak or vulnerable-either physically or mentally-and in need of a larger margin-of-safety.

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

    Science.gov (United States)

    Tops, Mattie; Boksem, Maarten A S

    2010-12-01

    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 predicted self-reported persistence. We hypothesized that, during a prolonged monotonous task, absorption would predict initial ERN amplitudes, constraint would delay declines in ERN amplitudes and deterioration of performance, and drive for reward would predict left RFA when a reward could be obtained. Study 2, employing EEG recordings, confirmed our predictions. The results showed that most traits that have in previous research been related to ERN amplitudes have a relationship with the motivational trait persistence in common. In addition, trait-context combinations that are likely associated with increased engagement predict larger ERN amplitudes and RFA. Together, these results support the hypothesis that engagement may be a common underlying factor predicting ERN amplitude.

  9. The mechanical master-slave manipulator: an instrument improving the performance in standardized tasks for endoscopic surgery.

    Science.gov (United States)

    Diks, J; Jaspers, J E N; Wisselink, W; de Mol, B A M J; Grimbergen, C A

    2007-06-01

    This study aimed to evaluate the feasibility and efficacy of a mechanical minimally invasive manipulator for endoscopic surgery. In contrast to currently available motorized master-slave manipulators, this mechanical manipulator consists of two purely mechanical, hand-controlled endoscopic arms with joints that allow seven degrees of freedom (DOF). For the study, 30 medical students performed four different tasks in a pelvic trainer box using either two conventional endoscopic needleholders or a set of mechanical manipulators. The exercise consisted of four different tasks: repositioning of coins, rope passing, passing of a suture through rings, and tying of a surgical knot. All experiments were recorded on videotape (S-VHS), and the data were analyzed afterwards by an independent observer using a quantitative time-action analysis. A significant difference in the number of total actions (including failures) favoring the mechanical manipulator group was shown in most exercises. A significant difference in failures per task was shown in favor of the mechanical manipulator group as well. There was no significant difference shown in the total time per exercise. The tasks clearly demonstrated the efficacy of the mechanical manipulator, although some technical flaws emerged during the experiments. Considering the fact that a first prototype of the mechanical manipulator was tested, modifications are to be expected in a next model. These experiments show the potential of the mechanical manipulator, and it is expected to be a competitive and economical instrument for endoscopic surgery in the near future.

  10. Gamification in thoracic surgical education: Using competition to fuel performance.

    Science.gov (United States)

    Mokadam, Nahush A; Lee, Richard; Vaporciyan, Ara A; Walker, Jennifer D; Cerfolio, Robert J; Hermsen, Joshua L; Baker, Craig J; Mark, Rebecca; Aloia, Lauren; Enter, Dan H; Carpenter, Andrea J; Moon, Marc R; Verrier, Edward D; Fann, James I

    2015-11-01

    In an effort to stimulate residents and trainers to increase their use of simulation training and the Thoracic Surgery Curriculum, a gamification strategy was developed in a friendly but competitive environment. "Top Gun." Low-fidelity simulators distributed annually were used for the technical competition. Baseline and final video assessments were performed, and 5 finalists were invited to compete in a live setting from 2013 to 2015. "Jeopardy." A screening examination was devised to test knowledge contained in the Thoracic Surgery Curriculum. The top 6 2-member teams were invited to compete in a live setting structured around the popular game show Jeopardy. "Top Gun." Over 3 years, there were 43 baseline and 34 final submissions. In all areas of assessment, there was demonstrable improvement. There was increasing evidence of simulation as seen by practice and ritualistic behavior. "Jeopardy." Sixty-eight individuals completed the screening examination, and 30 teams were formed. The largest representation came from the second-year residents in traditional programs. Contestants reported an average in-training examination percentile of 72.9. Finalists reported increased use of the Thoracic Surgery Curriculum by an average of 10 hours per week in preparation. The live competition was friendly, engaging, and spirited. This gamification approach focused on technical and cognitive skills, has been successfully implemented, and has encouraged the use of simulators and the Thoracic Surgery Curriculum. This framework may capitalize on the competitive nature of our trainees and can provide recognition of their achievements. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  11. Performance assessment in complex individual and team tasks

    Science.gov (United States)

    Eddy, Douglas R.

    1992-01-01

    Described here is an eclectic, performance based approach to assessing cognitive performance from multiple perspectives. The experience gained from assessing the effects of antihistamines and scenario difficulty on C (exp 2) decision making performance in Airborne Warning and Control Systems (AWACS) weapons director (WD) teams can serve as a model for realistic simulations in space operations. Emphasis is placed on the flexibility of measurement, hierarchical organization of measurement levels, data collection from multiple perspectives, and the difficulty of managing large amounts of data.

  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. Effects of age, task performance, and structural brain development on face processing.

    Science.gov (United States)

    Cohen Kadosh, Kathrin; Johnson, Mark H; Dick, Frederic; Cohen Kadosh, Roi; Blakemore, Sarah-Jayne

    2013-07-01

    In this combined structural and functional MRI developmental study, we tested 48 participants aged 7-37 years on 3 simple face-processing tasks (identity, expression, and gaze task), which were designed to yield very similar performance levels across the entire age range. The same participants then carried out 3 more difficult out-of-scanner tasks, which provided in-depth measures of changes in performance. For our analysis we adopted a novel, systematic approach that allowed us to differentiate age- from performance-related changes in the BOLD response in the 3 tasks, and compared these effects to concomitant changes in brain structure. The processing of all face aspects activated the core face-network across the age range, as well as additional and partially separable regions. Small task-specific activations in posterior regions were found to increase with age and were distinct from more widespread activations that varied as a function of individual task performance (but not of age). Our results demonstrate that activity during face-processing changes with age, and these effects are still observed when controlling for changes associated with differences in task performance. Moreover, we found that changes in white and gray matter volume were associated with changes in activation with age and performance in the out-of-scanner tasks.

  14. 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.

  15. 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.

  16. Spatial Reasoning Influences Students' Performance on Mathematics Tasks

    Science.gov (United States)

    Lowrie, Tom; Logan, Tracy; Ramful, Ajay

    2016-01-01

    Although the psychological literature has demonstrated that spatial reasoning and mathematics performance are correlated, there is scant research on these relationships in the middle years. The current study examined the commonalities and differences in students' performance on instruments that measured three spatial reasoning constructs and two…

  17. Great Performances: Creating Classroom-Based Assessment Tasks.

    Science.gov (United States)

    Lewin, Larry; Shoemaker, Betty Jean

    This book presents an approach to developing performance assessments. It begins with four steps for "Info In" and moves to four "Info Out" modes through which students can make their content understanding explicit for evaluation purposes. The first chapter is an overview of performance assessment in the classroom. Chapter 2 discusses the "Info In"…

  18. 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.

  19. 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.

  20. Machine Learning Based Online Performance Prediction for Runtime Parallelization and Task Scheduling

    Energy Technology Data Exchange (ETDEWEB)

    Li, J; Ma, X; Singh, K; Schulz, M; de Supinski, B R; McKee, S A

    2008-10-09

    With the emerging many-core paradigm, parallel programming must extend beyond its traditional realm of scientific applications. Converting existing sequential applications as well as developing next-generation software requires assistance from hardware, compilers and runtime systems to exploit parallelism transparently within applications. These systems must decompose applications into tasks that can be executed in parallel and then schedule those tasks to minimize load imbalance. However, many systems lack a priori knowledge about the execution time of all tasks to perform effective load balancing with low scheduling overhead. In this paper, we approach this fundamental problem using machine learning techniques first to generate performance models for all tasks and then applying those models to perform automatic performance prediction across program executions. We also extend an existing scheduling algorithm to use generated task cost estimates for online task partitioning and scheduling. We implement the above techniques in the pR framework, which transparently parallelizes scripts in the popular R language, and evaluate their performance and overhead with both a real-world application and a large number of synthetic representative test scripts. Our experimental results show that our proposed approach significantly improves task partitioning and scheduling, with maximum improvements of 21.8%, 40.3% and 22.1% and average improvements of 15.9%, 16.9% and 4.2% for LMM (a real R application) and synthetic test cases with independent and dependent tasks, respectively.

  1. Attentional capture by spoken language: effects on netballers' visual task performance.

    Science.gov (United States)

    Bishop, Daniel Tony; Moore, Sarah; Horne, Sara; Teszka, Robert

    2014-01-01

    In two experiments, participants performed visual detection, visual discrimination and decision-making tasks, in which a binary (left/right) response was required. In all experimental conditions, a spoken word ("left"/"right") was presented monaurally (left or right ear) at the onset of the visual stimulus. In Experiment 1, 26 non-athletes located a target amongst an array of distractors as quickly as possible, in both the presence and absence of spoken cues. Participants performed superiorly in the presence of valid cues, relative to invalid-cue and control conditions. In Experiment 2, 42 skilled netballers completed three tasks, in randomised order: a visual detection task, a visual discrimination task and a netball decision-making task - all in the presence of spoken cues. Our data showed that spoken auditory cues affected not only target detection, but also performance on more complex decision-making tasks: cues that were either spatially or semantically invalid slowed target detection time; spatially invalid cues impaired discrimination task accuracy; and cues that were either spatially or semantically valid improved accuracy and speeded decision-making time in the netball task. When studying visual perception and attention in sport, the impact of concomitant auditory information should be taken into account in order to achieve a more representative task design.

  2. Performance assessment of the risk index category for surgical site infection after colorectal surgery.

    Science.gov (United States)

    Watanabe, Masanori; Suzuki, Hideyuki; Nomura, Satoshi; Hanawa, Hidetsugu; Chihara, Naoto; Mizutani, Satoshi; Yoshino, Masanori; Uchida, Eiji

    2015-02-01

    The traditional National Healthcare Safety Network (previously National Nosocomial Infections Surveillance) risk index is used to predict the risk of surgical site infection across many operative procedures. However, this index may be too simple to predict risk in the various procedures performed in colorectal surgery. The aim of this study was to evaluate the usefulness of the risk index by analyzing the impact of the risk index factors on surgical site infection after abdominal colorectal surgery. Using our surgical site infection surveillance database, we analyzed retrospectively 538 consecutive patients who underwent abdominal colorectal surgery between 2005 and 2010. Correlations between surgical site infection and the following risk index factors were analyzed: length of operation, American Society of Anesthesiologists score, wound classification, and use of laparoscopy. The 75th percentile for length of operation was determined separately for open and laparoscopic surgery in the study model. Univariate analyses showed that surgical site infection was more strongly associated with a >75th percentile length of operation in the study model (odds ratio [OR], 2.07) than in the traditional risk index model (OR, 1.64). Multivariable analysis found that surgical site infection was independently associated with a >75th percentile length of operation in the study model (OR, 2.75; 95% confidence interval [CI], 1.66-4.55), American Society of Anesthesiologists score ≥3 (OR, 2.22; 95% CI, 1.10-4.34), wound classification ≥III (OR, 5.29; 95% CI, 2.62-10.69), and open surgery (OR, 2.21; 95% CI, 1.07-5.17). Performance of the risk index category was improved in the study model compared with the traditional model. The risk index category is sufficiently useful for predicting the risk of surgical site infection after abdominal colorectal surgery. However, the 75th percentile length of operation should be set separately for open and laparoscopic surgery.

  3. Task-Specific Motor Rehabilitation Therapy After Stroke Improves Performance in a Different Motor Task: Translational Evidence.

    Science.gov (United States)

    El Amki, M; Baumgartner, P; Bracko, O; Luft, A R; Wegener, S

    2017-01-14

    While the stroke survivor with a motor deficit strives for recovery of all aspects of daily life movements, neurorehabilitation training is often task specific and does not generalize to movements other than the ones trained. In rodent models of post-stroke recovery, this problem is poorly investigated as the training task is often the same as the one that measures motor function. The present study investigated whether motor training by pellet reaching translates into enhancement of different motor functions in rats after stroke. Adult rats were subjected to 60-min middle cerebral artery occlusion (MCAO). Five days after stroke, animals received either training consisting of 7 days of pellet reaching with the affected forelimb (n = 18) or no training (n = 18). Sensorimotor deficits were assessed using the sticky tape test and a composite neuroscore. Infarct volumes were measured by T2-weighted MRI on day 28. Both groups of rats showed similar lesion volume and forelimb impairment after stroke. Trained animals improved in the sticky tape test after day 7 post-stroke reaching peak performance on day 14. More reaching attempts during rehabilitation were associated with a better performance in the sticky tape removal time. Task-oriented motor training generalizes to other motor functions after experimental stroke. Training intensity correlates with recovery.

  4. 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...... demands affect young and elderly women differently. Thus the mentally demanding computer task had a more pronounced effect on the elderly than on the young. In contrast to the results in the reference task, the same level of muscle activity for most muscles and the same level of self-reported difficulty...... 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...

  5. 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.

  6. Experimental evaluation of the influence of various rests on task performance

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-01-01

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

  7. Effect of Water Immersion on Dual-task Performance: Implications for Aquatic Therapy.

    Science.gov (United States)

    Schaefer, Sydney Y; Louder, Talin J; Foster, Shayla; Bressel, Eadric

    2016-09-01

    Much is known about cardiovascular and biomechanical responses to exercise during water immersion, yet an understanding of the higher-order neural responses to water immersion is unclear. The purpose of this study was to compare cognitive and motor performance between land and water environments using a dual-task paradigm, which served as an indirect measure of cortical processing. A quasi-experimental crossover research design is used. Twenty-two healthy participants (age = 24.3 ± 5.24 years) and a single-case patient (age = 73) with mild cognitive impairment performed a cognitive (auditory vigilance) and motor (standing balance) task separately (single-task condition) and simultaneously (dual-task condition) on land and in chest-deep water. Listening errors from the auditory vigilance task and centre of pressure (CoP) area for the balance task measured cognitive and motor performance, respectively. Listening errors for the single-task and dual-task conditions were 42% and 45% lower for the water than land condition, respectively (effect size [ES] = 0.38 and 0.55). CoP area for the single-task and dual-task conditions, however, were 115% and 164% lower on land than in water, respectively, and were lower (≈8-33%) when balancing concurrently with the auditory vigilance task compared with balancing alone, regardless of environment (ES = 0.23-1.7). This trend was consistent for the single-case patient. Participants tended to make fewer 'cognitive' errors while immersed chest-deep in water than on land. These same participants also tended to display less postural sway under dual-task conditions, but more in water than on land. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  8. 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......Many stroke patients are prescribed canes or other mobility assistive devices. Once taken home, these mobility assistive devices are often abandoned or misused. A means for assessing the use of the cane in the home and community settings is required to assist clinicians in the prescription...

  9. The Effect of Background Music and Background Noise on the Task Performance of Introverts and Extraverts

    Science.gov (United States)

    Cassidy, Gianna; MacDonald, Raymond A. R.

    2007-01-01

    The study investigated the effects of music with high arousal potential and negative affect (HA), music with low arousal potential and positive affect (LA), and everyday noise, on the cognitive task performance of introverts and extraverts. Forty participants completed five cognitive tasks: immediate recall, free recall, numerical and delayed…

  10. Self-Reported Stickiness of Mind-Wandering Affects Task Performance

    NARCIS (Netherlands)

    van Vugt, Marieke K; Broers, Nico

    2016-01-01

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

  11. Age, Gender, and Training in Children's Performance of Piaget's Horizontality Task.

    Science.gov (United States)

    Parameswaran, Gowri

    2003-01-01

    Presents a study in which children (n=600), ages five to nine, completed Jean Piaget's horizontality task using a square water bottle. Finds a significant sex difference in the pretest performance of the horizontality task beginning with eight year olds. Includes references. (CMK)

  12. Self-Reported Stickiness of Mind-Wandering Affects Task Performance

    NARCIS (Netherlands)

    van Vugt, Marieke K; Broers, Nico

    2016-01-01

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

  13. Effects of a standing and three dynamic workstations on computer task performance and cognitive function tests

    NARCIS (Netherlands)

    Commissaris, D.A.C.M.; Könemann, R.; Hiemstra-van Mastrigt, S.; Burford, E.M.; Botter, J.; Douwes, M.; Ellegast, R.P.

    2014-01-01

    Sedentary work entails health risks. Dynamic (or active) workstations, at which computer tasks can be combined with physical activity, may reduce the risks of sedentary behaviour. The aim of this study was to evaluate short term task performance while working on three dynamic workstations: a treadmi

  14. Gender and Performance in Mathematical Tasks: Does the Context Make a Difference?

    Science.gov (United States)

    Zohar, Anat; Gershikov, Anna

    2008-01-01

    This study investigates how the context of mathematical tasks affects the performance of young children (ages 5-11). Subjects were 523 children from age 5 to 11. Three contexts of mathematical tasks (stereotypically boys' contexts, stereotypically girls' contexts and neutral contexts) are examined in three age groups (young, medium, and old).…

  15. Age, Gender, and Training in Children's Performance of Piaget's Horizontality Task.

    Science.gov (United States)

    Parameswaran, Gowri

    2003-01-01

    Presents a study in which children (n=600), ages five to nine, completed Jean Piaget's horizontality task using a square water bottle. Finds a significant sex difference in the pretest performance of the horizontality task beginning with eight year olds. Includes references. (CMK)

  16. Gender and Performance in Mathematical Tasks: Does the Context Make a Difference?

    Science.gov (United States)

    Zohar, Anat; Gershikov, Anna

    2008-01-01

    This study investigates how the context of mathematical tasks affects the performance of young children (ages 5-11). Subjects were 523 children from age 5 to 11. Three contexts of mathematical tasks (stereotypically boys' contexts, stereotypically girls' contexts and neutral contexts) are examined in three age groups (young, medium, and old).…

  17. The Effect of Background Music and Background Noise on the Task Performance of Introverts and Extraverts

    Science.gov (United States)

    Cassidy, Gianna; MacDonald, Raymond A. R.

    2007-01-01

    The study investigated the effects of music with high arousal potential and negative affect (HA), music with low arousal potential and positive affect (LA), and everyday noise, on the cognitive task performance of introverts and extraverts. Forty participants completed five cognitive tasks: immediate recall, free recall, numerical and delayed…

  18. The performance of college students on piaget-type tasks dealing with distance, time, and speed

    Science.gov (United States)

    Poduska, Ervin; Phillips, Darrell G.

    Research was done to probe and extend Piaget's theory of the conception of speed. Specifically tested was the hypothesis that there is no hierarchical relationship in performance on the following Piaget-type tasks: conservation of distance, asymmetric series of speeds, one-to-many (circular) speeds, symmetric speeds, time, and proportional reasoning. The research also tested the gender-related performance on these six tasks. One hundred freshman and sophomore college students were shown demonstrations of equipment individually for each of the six tasks. A set of open-ended questions based on the demonstrations was administered to each subject in a 45-minute interview. Subjects were scored as pass on a given task if they manipulated objects in certain ways and gave specific types of explanations. A scalogram analysis of the data yielded a z-score of - 3.7 which indicated that subjects passed the task in a certain sequence. The tasks were found to form a unidimensional scale and to be increasingly difficult in the order listed above. A chi-square test for two independent samples showed a significant difference (alpha = 0.05) in performance between males and females on all speed tasks. No significant differences in performance between males and females were found for the distance and time tasks.

  19. Does previous presentation of verbal fluency tasks affect verb fluency performance?

    Directory of Open Access Journals (Sweden)

    Bárbara Costa Beber

    Full Text Available Background : Performance on the verb fluency (VF task may be influenced by administration procedures and demographic factors of each population. Objective : The aim of this study was to verify whether the previous administration of semantic and phonemic verbal fluency tasks can influence performance on VF; and to analyze the correlation of VF performance with education, age and type of errors in Brazilian healthy elderly. Methods : Sixty-two participants were subdivided into experimental (semantic and the phonemic fluency tasks were administered before the VF and control groups (VF only. The total score and the types of errors on the VF task were determined. Additional information was computed for the correlational analysis. Results : VF performance did not differ statistically between experimental and control groups, but correlated positively with education and negatively with intrusions. Conclusion : The lack of influence of other verbal fluency tasks on performance of the VF task in elderly individuals allows the use of this order of administration. A strong influence of educational level on VF task performance reinforces the need for further studies in different populations.

  20. 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

    2016-01-01

    OBJECTIVE: 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 wi......-task performance was associated with better cognitive performance. CONCLUSION: 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.......OBJECTIVE: 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. METHODS: Baseline results from 185 participants (50-90 years old) in the single...

  1. Toward a mathematical formalism of performance, task difficulty, and activation

    Science.gov (United States)

    Samaras, George M.

    1988-01-01

    The rudiments of a mathematical formalism for handling operational, physiological, and psychological concepts are developed for use by the man-machine system design engineer. The formalism provides a framework for developing a structured, systematic approach to the interface design problem, using existing mathematical tools, and simplifying the problem of telling a machine how to measure and use performance.

  2. Mental Workload Manipulation Using Multiple Homogeneous Tasks: Performance Effects

    Science.gov (United States)

    2010-09-03

    interval, as they were in Colle and Reid (2005) and in Calkin (2007). These accomplishment curves also were related to the SWAT ratings. Performance and...4.0. Aberdeen Proving Ground, MD: U.S. Army Research Laboratory. Calkin , B. (2007). Parameters affecting mental workload and the number of simulated

  3. Arousal and Task Performance: The Ubiquitous U-Curve,

    Science.gov (United States)

    1979-08-01

    UNCLASSIFIED ARL/SYS-NOTE-68 N L U /ll/// EEEEEEEL ,. I go .1 8 I1.25 _ . MICROCOPY RESOLUTION TESI CHART NAIJONAL BUREAU (Of STANDARIUS 1b64 A ARL-SYS...McGraw Hill Book Company. N.Y. 5. Corcoran, D. W. J. (1963). Individual differences in performance after loss of sleep. Un- published doctoral dissertation

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

    Science.gov (United States)

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

    2016-10-01

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

  5. Imaging "brain strain" in youth athletes with mild traumatic brain injury during dual-task performance.

    Science.gov (United States)

    Sinopoli, Katia J; Chen, Jen-Kai; Wells, Greg; Fait, Philippe; Ptito, Alain; Taha, Tim; Keightley, Michelle

    2014-11-15

    Mild traumatic brain injury (mTBI) is a common cause of injury in youth athletes. Much of what is known about the sequelae of mTBI is yielded from the adult literature, and it appears that it is mainly those with persistent post-injury symptoms who have ongoing cognitive and neural abnormalities. However, most studies have employed single-task paradigms, which may not be challenging enough to uncover subtle deficits. We sought to examine the neural correlates of dual-task performance in male athletes aged 9-15 years using a functional neuroimaging protocol. Participants included 13 youths with a history of mTBI three to six months prior to testing and 14 typically-developing controls. All participants completed a working memory task in isolation (single-task) and while completing a concurrent motor task (dual-task); neural activity during performance was then compared between groups. Although working memory performance was similar during the single-task condition, increased working memory load resulted in an altered pattern of neural activation in key working memory areas (i.e., dorsolateral prefrontal and parietal cortices) in youth with mTBI relative to controls. During the dual-task condition, accuracy was similar between groups but injured youth performed slower than typically-developing controls, suggesting a speed-accuracy tradeoff in the mTBI group only. The injured youths also exhibited abnormal recruitment of brain structures involved in both working memory and dual-tasking. These data show that the dual-task paradigm can uncover functional impairments in youth with mTBI who are not highly symptomatic and who do not exhibit neuropsychological dysfunction. Moreover, neural recruitment abnormalities were noted in both task conditions, which we argue suggests mTBI-related disruptions in achieving efficient cognitive control and allocation of processing resources.

  6. Indications and results of emergency surgical airways performed by a physician-staffed helicopter emergency service

    NARCIS (Netherlands)

    Peters, J.; Bruijstens, L.; Ploeg, J. van der; Tan, E.; Hoogerwerf, N.; Edwards, M.J.

    2015-01-01

    BACKGROUND: Airway management is essential in critically ill or injured patients. In a "can't intubate, can't oxygenate" scenario, an emergency surgical airway (ESA), similar to a cricothyroidotomy, is the final step in airway management. This procedure is infrequently performed in the prehospital

  7. How to train surgical residents to perform laparoscopic roux-en-Y gastric bypass safely

    NARCIS (Netherlands)

    G.I.T. Iordens (Gijs); R.A. Klaassen (René); E.M.M. van Lieshout (Esther); B.I. Cleffken (Berry); E. van der Harst (Erwin)

    2012-01-01

    textabstractBackground As a result of increasing numbers of patients with morbid obesity there is a worldwide demand for bariatric surgeons. The Roux-en-Y gastric bypass, nowadays performed mostly laparoscopically (LRYGB), has been proven to be a highly effective surgical treatment for morbid

  8. 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…

  9. 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.

  10. Effect of the survival judgment task on memory performance in subclinically depressed people

    Directory of Open Access Journals (Sweden)

    Rui eNouchi

    2012-04-01

    Full Text Available Many reports have described that a survival judgment task that requires participants to judge words according to their relevance to a survival situation can engender better recall than that obtained in other judgment tasks such as semantic or self-judgment tasks. We investigated whether memory enhancement related to the survival judgment task is elicited or not in subclinically depressed participants. Based on the BDI Score, participants were classified as either depressed or non-depressed participants. Then 20 depressed participants and 24 non-depressed participants performed a survival judgment task and an autobiographical recall task. Results showed memory enhancement related to the survival judgment task in both depressed and non-depressed participants, but showed lower memory enhancement related to the survival judgment task in depressed participants than in non-depressed participants. These results suggest that the survival judgment task benefit is a robust phenomenon. Moreover, that benefit was reduced by depressed emotion. The combination hypothesis better explains the mechanism of memory enhancement related to the survival judgment task than the functional, emotional and arousal or congruency hypothesis does.

  11. 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

    at task level, which can be performed with fewer resources than a more detailed analysis of specific errors for each task. The generic tasks are presented with estimated Human Error Probabili-ties (HEPs) based on and extrapolated from the HRA literature, and estimates are compared with samples of measures...... on estimates derived from industries other than rail and the general warning that a task-based analysis is less precise than an error-based one. The authors recommend that estimates be adjusted to actual measures of task failures when feasible....... collaboration with Banedanmark. The estimates provided are based on HRA literature and primarily the HEART method, being recently been adapted for railway tasks by the British Rail Safety and Stan-dards Board (RSSB). The method presented in this report differs from the RSSB tool by supporting an analysis...

  12. Anticipatory affect during action preparation: evidence from backward compatibility in dual-task performance.

    Science.gov (United States)

    Eder, Andreas B; Pfister, Roland; Dignath, David; Hommel, Bernhard

    2016-07-14

    Upcoming responses in the second of two subsequently performed tasks can speed up compatible responses in the temporally preceding first task. Two experiments extend previous demonstration of such backward compatibility to affective features: responses to affective stimuli were faster in Task 1 when an affectively compatible response effect was anticipated for Task 2. This emotional backward-compatibility effect demonstrates that representations of the affective consequences of the Task 2 response were activated before the selection of a response in Task 1 was completed. This finding is problematic for the assumption of a serial stimulus-response translation stage. It also shows that the affective consequence of a response is anticipated during, and has an impact on stimulus-response translation, which implies that action planning considers codes representing and predicting the emotional consequences of actions. Implications for the control of emotional actions are discussed.

  13. A meta-analysis of reinforcement sensitivity theory: on performance parameters in reinforcement tasks.

    Science.gov (United States)

    Leue, Anja; Beauducel, André

    2008-11-01

    J. A. Gray's Reinforcement Sensitivity Theory (RST) has produced a wealth of quasi-experimental studies in more than 35 years of research on personality and reinforcement sensitivity. The present meta-analysis builds on this literature by investigating RST in conflict and nonconflict reinforcement tasks in humans. Based on random-effects meta-analysis, we confirmed RST predictions of performance parameters (e.g., number of responses, reaction time) in reinforcement tasks for impulsivity- and anxiety-related traits. In studies on anxiety-related traits, the effect size variance was smaller for conflict tasks than for nonconflict tasks. A larger mean effect size and a larger variability of effect sizes were found for conflict compared to nonconflict tasks in studies on impulsivity-related traits. Our results suggest that problems with RST confirmation in reinforcement tasks are at least partly caused by insufficient statistical power of primary studies, and thus, encourage future research on RST.

  14. Goal Setting and Task Performance: 1969-1980

    Science.gov (United States)

    1980-06-01

    Organizatioral Effectivene ss Program, office of Naval Research(Code 452),under Contract No.1 Nh7-C-FT APPROVED FOR PUBLIC RELIASE : DISTRIBUTION UNL...to set goals in the participative goal conditions than in the assigned conditions which may have accounted for the higher performance of this groc"p...goal acceptance and choice. (b) Values . When the perceived value of attaining or trying for a goal is higher, the goal is more likely to be accepted

  15. Emotional reactivity and cognitive performance in aversively motivated tasks: a comparison between four rat strains

    Directory of Open Access Journals (Sweden)

    van Reenen Cornelis G

    2009-12-01

    Full Text Available Abstract Background Cognitive function might be affected by the subjects' emotional reactivity. We assessed whether behavior in different tests of emotional reactivity is correlated with performance in aversively motivated learning tasks, using four strains of rats generally considered to have a different emotional reactivity. Methods The performance of male Brown Norway, Lewis, Fischer 344, and Wistar Kyoto rats in open field (OF, elevated plus-maze (EPM, and circular light-dark preference box (cLDB tasks, which are believed to provide measures of emotional reactivity, was evaluated. Spatial working and reference memory were assessed in two aversively motivated learning and memory tasks: the standard and the "repeated acquisition" versions of the Morris water maze escape task, respectively. All rats were also tested in a passive avoidance task. At the end of the study, levels of serotonin (5-HT and 5-hydroxyindoleacetic acid, and 5-HT turnover in the hippocampus and frontal cortex were determined. Results Strain differences showed a complex pattern across behavioral tests and serotonergic measures. Fischer 344 rats had the poorest performance in both versions of the Morris water escape task, whereas Brown Norway rats performed these tasks very well but the passive avoidance task poorly. Neither correlation analysis nor principal component analysis provided convincing support for the notion that OF, EPM, and cLDB tasks measure the same underlying trait. Conclusions Our findings do not support the hypothesis that the level of emotional reactivity modulates cognitive performance in aversively motivated tasks. Concepts such as "emotional reactivity" and "learning and memory" cannot adequately be tapped with only one behavioral test. Our results emphasize the need for multiple testing.

  16. Performance study involving a force-reflecting joystick for spastic individuals performing two types of tracking tasks.

    Science.gov (United States)

    Repperger, D W; Phillips, C A; Chelette, T L

    1995-10-01

    10 upper-extremity spastic subjects and 10 normal subjects were studied with a force-reflecting joystick in the performance of a continuous time-tracking task as well as an acquisition task termed, "Fitts' Law." Certain force-reflection paradigms, in a spatial sense, allowed the spastic subjects to obtain performance proficiency near levels of the normal subjects as measured by a capacity metric.

  17. Trunk muscle activity during the simultaneous performance of two motor tasks.

    Science.gov (United States)

    Farley, B G; Koshland, G F

    2000-12-01

    A unique feature of trunk muscles is that they can be activated to meet functional requirements for combined behaviors, including those related to posture and breathing. Trunk muscles therefore may have developed mechanisms for dealing with simultaneous inputs for different task requirements. This study was designed to test the hypothesis that a linear addition in trunk muscle activities would occur when an isometric trunk task and a pulsed expiration task was performed simultaneously. Surface electromyograms (EMG) were recorded from four trunk regions (medial and lateral back, upper and lower lateral abdomen) in sitting during the performance of the individual isometric trunk task, the individual pressure task, and the combined task (isometric trunk and pressure task). The direction of static holding for the isometric trunk task was varied between flexion and extension positions. For the pressure task subjects produced two consecutive pressure pulses (2/s) to a target oral pressure. For each muscle recording, a linear prediction was calculated from the mathematical addition of the EMG recorded from the individual trunk and pressure tasks. This linear prediction was compared to the actual muscle activity recorded during the combined task. Typically the EMG from two muscles showed linear addition, such that the relative contribution of muscle activity did not change for the combined task. This suggests that the motor commands for each task reached these motor neuron pools essentially unmodified. The other two muscles showed nonlinear combination of two EMG patterns. That is, qualitatively both EMG patterns, specific to each command, were evident in the measured EMG traces for the combined task, but quantitatively the muscle did not meet all criteria for linear addition. Linear addition may provide a simple mechanism for combining breathing-related behaviors (expiratory efforts) with other trunk behaviors (holding against gravity). This suggests that some muscles can

  18. Argumentative and narrative written task performance: Differential effects of critical thinking

    Directory of Open Access Journals (Sweden)

    Dabaghi, Azizollah

    2013-01-01

    Full Text Available This study compares the differential role of critical thinking in learners’ performance on argumentative and narrative written tasks. The study involved the measurement of 70 upper-intermediate learners’ critical thinking using the Watson-Glaser Critical Thinking Appraisal (WGCTA as well as the elicitation of their performance on the written narrative and argumentative tasks. While the argumentative task required that learners write an argumentative essay giving their opinions concerning the effect of technology on human’s life, the narrative task involved learners in narrating a story based on a picture as a visual cue. Concerning the narrative task, only a significant negative correlation was observed between drawing inferences and the two accuracy measures of the narrative task. With regards to the argumentative task, the correlation analysis showed negative relationships between the three measures of argumentative task fluency and students’ score on the Drawing Inferences subscale. Results of the complexity measures revealed that the syntactic complexity of produced argumentations was affected by learners’ ability to make deductions, interpreting evidence, and evaluating arguments. Finally, with regards to the accuracy of the performances, it was found that only Recognizing Assumptions had a significant, but negative, relationship with error-free clauses percentage and error-free T-unit percentage.

  19. Age-Related Changes in Brain Activation Underlying Single- and Dual-Task Performance: Visuomanual Drawing and Mental Arithmetic

    Science.gov (United States)

    Van Impe, A.; Coxon, J. P.; Goble, D. J.; Wenderoth, N.; Swinnen, S. P.

    2011-01-01

    Depending on task combination, dual-tasking can either be performed successfully or can lead to performance decrements in one or both tasks. Interference is believed to be caused by limitations in central processing, i.e. structural interference between the neural activation patterns associated with each task. In the present study, single- and…

  20. Formal Derivation of Lotka-Volterra-Haken Amplitude Equations of Task-Related Brain Activity in Multiple, Consecutively Performed Tasks

    Science.gov (United States)

    Frank, T. D.

    The Lotka-Volterra-Haken equations have been frequently used in ecology and pattern formation. Recently, the equations have been proposed by several research groups as amplitude equations for task-related patterns of brain activity. In this theoretical study, the focus is on the circular causality aspect of pattern formation systems as formulated within the framework of synergetics. Accordingly, the stable modes of a pattern formation system inhibit the unstable modes, whereas the unstable modes excite the stable modes. Using this circular causality principle it is shown that under certain conditions the Lotka-Volterra-Haken amplitude equations can be derived from a general model of brain activity akin to the Wilson-Cowan model. The model captures the amplitude dynamics for brain activity patterns in experiments involving several consecutively performed multiple-choice tasks. This is explicitly demonstrated for two-choice tasks involving grasping and walking. A comment on the relevance of the theoretical framework for clinical psychology and schizophrenia is given as well.

  1. Task-dependent modulation of primary afferent depolarization in cervical spinal cord of monkeys performing an instructed delay task.

    Science.gov (United States)

    Seki, Kazuhiko; Perlmutter, Steve I; Fetz, Eberhard E

    2009-07-01

    Task-dependent modulation of primary afferent depolarization (PAD) was studied in the cervical spinal cord of two monkeys performing a wrist flexion and extension task with an instructed delay period. We implanted two nerve cuff electrodes on proximal and distal parts of the superficial radial nerve (SR) and a recording chamber over a hemi-laminectomy in the lower cervical vertebrae. Antidromic volleys (ADVs) in the SR were evoked by intraspinal microstimuli (ISMS, 3-10 Hz, 3-30 microA) applied through a tungsten microelectrode, and the area of each ADV was measured. In total, 434 ADVs were evoked by ISMS in two monkeys, with onset latency consistently shorter in the proximal than distal cuffs. Estimated conduction velocity suggest that most ADVs were caused by action potentials in cutaneous fibers originating from low-threshold tactile receptors. Modulation of the size of ADVs as a function of the task was examined in 281 ADVs induced by ISMS applied at 78 different intraspinal sites. The ADVs were significantly facilitated during active movement in both flexion and extension (Pmodulation of PAD. This facilitation started 400-900 ms before the onset of EMG activity. Such pre-EMG modulation is hard to explain by movement-induced reafference and probably is associated with descending motor commands.

  2. Performance comparison of heuristic algorithms for task scheduling in IaaS cloud computing environment.

    Science.gov (United States)

    Madni, Syed Hamid Hussain; Abd Latiff, Muhammad Shafie; Abdullahi, Mohammed; Abdulhamid, Shafi'i Muhammad; Usman, Mohammed Joda

    2017-01-01

    Cloud computing infrastructure is suitable for meeting computational needs of large task sizes. Optimal scheduling of tasks in cloud computing environment has been proved to be an NP-complete problem, hence the need for the application of heuristic methods. Several heuristic algorithms have been developed and used in addressing this problem, but choosing the appropriate algorithm for solving task assignment problem of a particular nature is difficult since the methods are developed under different assumptions. Therefore, six rule based heuristic algorithms are implemented and used to schedule autonomous tasks in homogeneous and heterogeneous environments with the aim of comparing their performance in terms of cost, degree of imbalance, makespan and throughput. First Come First Serve (FCFS), Minimum Completion Time (MCT), Minimum Execution Time (MET), Max-min, Min-min and Sufferage are the heuristic algorithms considered for the performance comparison and analysis of task scheduling in cloud computing.

  3. State of the practice for pediatric surgery--career satisfaction and concerns. A report from the American Pediatric Surgical Association Task Force on Family Issues.

    Science.gov (United States)

    Katz, Aviva; Mallory, Baird; Gilbert, James C; Bethel, Colin; Hayes-Jordan, Andrea A; Saito, Jacqueline M; Tomita, Sandra S; Walsh, Danielle S; Shin, Cathy E; Wesley, John R; Farmer, Diana

    2010-10-01

    There has been increasing interest and concern raised in the surgical literature regarding changes in the culture of surgical training and practice, and the impact these changes may have on surgeon stress and the appeal of a career in surgery. We surveyed pediatric surgeons and their partners to collect information on career satisfaction and work-family balance. The American Pediatric Surgical Association Task Force on Family Issues developed separate survey instruments for both pediatric surgeons and their partners that requested demographic data and information regarding the impact of surgical training and practice on the surgeon's opportunity to be involved with his/her family. We found that 96% of pediatric surgeons were satisfied with their career choice. Of concern was the lack of balance, with little time available for family, noted by both pediatric surgeons and their partners. The issues of work-family balance and its impact on surgeon stress and burnout should be addressed in both pediatric surgery training and practice. The American Pediatric Surgical Association is positioned to play a leading role in this effort. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Influence of stereoscopic vision on task performance with an operating microscope

    NARCIS (Netherlands)

    Nibourg, Lisanne M.; Wanders, Wouter; Cornelissen, Frans W.; Koopmans, Steven A.

    PURPOSE: To determine the extent to which stereoscopic depth perception influences the performance of tasks executed under an operating microscope. SETTING: Laboratory of Experimental Ophthalmology, University Medical Center Groningen, the Netherlands. DESIGN: Experimental study. METHODS: Medical

  5. Performance in a planning task: The (ir)relevance of interface style and users’ cognitive style

    NARCIS (Netherlands)

    Van Nimwegen, Christof; Burgos, Daniel

    2005-01-01

    This research investigates whether interface style (internalization or externalization) influences performance in a problem solving task. Assistance from a user interface during problem solving is often thought to make interactions easier. Interfaces often display relevant information, making recall

  6. Dual-task performance under acute stress in female adolescents with borderline personality disorder.

    Science.gov (United States)

    Kaess, Michael; Parzer, Peter; Koenig, Julian; Resch, Franz; Brunner, Romuald

    2016-09-01

    Research to elucidate early alterations of higher cognitive processes in adolescents with BPD is rare. This study investigated differences in dual-task performance in adolescents with BPD during stress and non-stress conditions. The study sample comprised 30 female adolescents with BPD and 34 healthy controls. The impact of stress on dual-task performance was measured using a standardized stressor. Self-reports of distress and measures of heart rate (HR) were obtained to measure stress reactivity. There were no group differences in task performance. Under stress conditions, the performance on the auditory task decreased in both groups but without significant group differences. Healthy controls showed an increase of mean HR after stress induction compared to no change in the BPD group. The finding of attenuated HR response to acute stress in adolescent patients with BPD may contradict current theories that the affective hyperresponsivity in BPD is based on a biologically determined mechanism.

  7. INFLUENCE OF SEPARATED HOMES ON TASK PERFORMANCE AND PERSONALITY DEVELOPMENT OF SCHOOL CHILDREN IN ONDO METROPOLIS

    National Research Council Canada - National Science Library

    Akindele Oluwafemi; Iwayemi Ayodeji; Idoko O Joseph

    2017-01-01

    The study looked into the influence of separated homes on task performance and personality development of school children in Ondo State metropolis with particular focus on the Okitipupa Local Government Area...

  8. Influence of stereoscopic vision on task performance with an operating microscope

    NARCIS (Netherlands)

    Nibourg, Lisanne M.; Wanders, Wouter; Cornelissen, Frans W.; Koopmans, Steven A.

    2015-01-01

    PURPOSE: To determine the extent to which stereoscopic depth perception influences the performance of tasks executed under an operating microscope. SETTING: Laboratory of Experimental Ophthalmology, University Medical Center Groningen, the Netherlands. DESIGN: Experimental study. METHODS: Medical st

  9. Fostering complex learning-task performance through scripting student use of computer supported representational tools

    NARCIS (Netherlands)

    Slof, Bert; Erkens, Gijs; Kirschner, Paul A.; Janssen, Jeroen; Phielix, Chris

    2010-01-01

    Slof, B., Erkens, G., Kirschner, P. A., Janssen, J., & Phielix, C. (2010). Fostering complex learning-task performance through scripting student use of computer supported representational tools. Computers & Education, 55(4), 1707-1720.

  10. 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.

  11. Dual-task motor performance with a tongue-operated assistive technology compared with hand operations

    Directory of Open Access Journals (Sweden)

    Johnson Ashley N

    2012-01-01

    Full Text Available Abstract Background To provide an alternative motor modality for control, navigation, and communication in individuals suffering from impairment or disability in hand functions, a Tongue Drive System (TDS has been developed that allows for real time tracking of tongue motion in an unobtrusive, wireless, and wearable device that utilizes the magnetic field generated by a miniature disk shaped magnetic tracer attached to the tip of the tongue. The purpose of the study was to compare the influence of a concurrent motor or cognitive task on various aspects of simple movement control between hand and tongue using the TDS technology. Methods Thirteen young able-bodied adults performed rapid and slow goal-directed movements of hand and tongue (with TDS with and without a concurrent motor (hand or tongue or cognitive (arithmetic and memory task. Changes in reaction time, completion time, speed, correctness, accuracy, variability of displacement, and variability of time due to the addition of a concurrent task were compared between hand and tongue. Results The influence of an additional concurrent task on motor performance was similar between the hand and tongue for slow movement in controlling their displacement. In rapid movement with a concurrent motor task, most aspects of motor performance were degraded in hand, while tongue speed during rapid continuous task was maintained. With a concurrent cognitive task, most aspects of motor performance were degraded in tongue, while hand accuracy during the rapid discrete task and hand speed during the rapid continuous task were maintained. Conclusion Rapid goal-directed hand and tongue movements were more consistently susceptible to interference from concurrent motor and cognitive tasks, respectively, compared with the other movement.

  12. Visual task performance using a monocular see-through head-mounted display (HMD) while walking.

    Science.gov (United States)

    Mustonen, Terhi; Berg, Mikko; Kaistinen, Jyrki; Kawai, Takashi; Häkkinen, Jukka

    2013-12-01

    A monocular see-through head-mounted display (HMD) allows the user to view displayed information while simultaneously interacting with the surrounding environment. This configuration lets people use HMDs while they are moving, such as while walking. However, sharing attention between the display and environment can compromise a person's performance in any ongoing task, and controlling one's gait may add further challenges. In this study, the authors investigated how the requirements of HMD-administered visual tasks altered users' performance while they were walking. Twenty-four university students completed 3 cognitive tasks (high- and low-working memory load, visual vigilance) on an HMD while seated and while simultaneously performing a paced walking task in a controlled environment. The results show that paced walking worsened performance (d', reaction time) in all HMD-administered tasks, but visual vigilance deteriorated more than memory performance. The HMD-administered tasks also worsened walking performance (speed, path overruns) in a manner that varied according to the overall demands of the task. These results suggest that people's ability to process information displayed on an HMD may worsen while they are in motion. Furthermore, the use of an HMD can critically alter a person's natural performance, such as their ability to guide and control their gait. In particular, visual tasks that involve constant monitoring of the HMD should be avoided. These findings highlight the need for careful consideration of the type and difficulty of information that can be presented through HMDs while still letting the user achieve an acceptable overall level of performance in various contexts of use. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  13. Self-reported stickiness of mind-wandering affects task performance

    Directory of Open Access Journals (Sweden)

    Marieke Karlijn Van Vugt

    2016-05-01

    Full Text Available When asked to perform a certain task, we typically spend a decent amount of time thinking thoughts unrelated to that task--a phenomenon referred to as 'mind-wandering.' It is thought that this mind-wandering is driven at least in part by our unfinished goals and concerns. Previous studies have shown that just after presenting a participant with their own concerns, their reports of task-unrelated thinking increased somewhat. However, effects of these concerns on task performance were somewhat inconsistent. In this study we take the opposite approach, and examine whether task performance depends on the self-reported thought content. Specifically, a particularly intriguing aspect of mind-wandering that has hitherto received little attention is the difficulty of disengaging from it, in other words, the ''stickiness'' of the thoughts. While presenting participants with their own concerns was not associated with clear effects on task performance, we showed that the reports of off-task thinking and variability of response times increased with the amount of self-reported stickiness of thoughts. This suggests that the stickiness of mind-wandering is a relevant variable, and participants are able to meaningfully report on it.

  14. Self-Reported Stickiness of Mind-Wandering Affects Task Performance.

    Science.gov (United States)

    van Vugt, Marieke K; Broers, Nico

    2016-01-01

    When asked to perform a certain task, we typically spend a decent amount of time thinking thoughts unrelated to that task-a phenomenon referred to as "mind-wandering." It is thought that this mind-wandering is driven at least in part by our unfinished goals and concerns. Previous studies have shown that just after presenting a participant with their own concerns, their reports of task-unrelated thinking increased somewhat. However, effects of these concerns on task performance were somewhat inconsistent. In this study we take the opposite approach, and examine whether task performance depends on the self-reported thought content. Specifically, a particularly intriguing aspect of mind-wandering that has hitherto received little attention is the difficulty of disengaging from it, in other words, the "stickiness" of the thoughts. While presenting participants with their own concerns was not associated with clear effects on task performance, we showed that the reports of off-task thinking and variability of response times increased with the amount of self-reported stickiness of thoughts. This suggests that the stickiness of mind-wandering is a relevant variable, and participants are able to meaningfully report on it.

  15. Cognitive performance in senile dementia of the Alzheimer's type: the Kitchen Task Assessment.

    Science.gov (United States)

    Baum, C; Edwards, D F

    1993-05-01

    The Kitchen Task Assessment (KTA) is a functional measure that records the level of cognitive support required by a person with Senile Dementia of the Alzheimer's Type (SDAT) to complete a cooking task successfully. The results allow the clinician to help caregivers understand the level of support the impaired person needs to perform daily living tasks. This paper presents the validity and internal consistency of the KTA. Data were collected from 106 persons diagnosed with SDAT. Construct validity was established by examining the relationship between subjects' performance on the KTA and standard neuropsychological measures.

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

    Science.gov (United States)

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

    2011-01-01

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

  17. Time-on-task decrements in "steer clear" performance of patients with sleep apnea and narcolepsy

    Science.gov (United States)

    Findley, L. J.; Suratt, P. M.; Dinges, D. F.

    1999-01-01

    Loss of attention with time-on-task reflects the increasing instability of the waking state during performance in experimentally induced sleepiness. To determine whether patients with disorders of excessive sleepiness also displayed time-on-task decrements indicative of wake state instability, visual sustained attention performance on "Steer Clear," a computerized simple RT driving simulation task, was compared among 31 patients with untreated sleep apnea, 16 patients with narcolepsy, and 14 healthy control subjects. Vigilance decrement functions were generated by analyzing the number of collisions in each of six four-minute periods of Steer Clear task performance in a mixed-model analysis of variance and linear regression equations. As expected, patients had more Steer Clear collisions than control subjects (p=0.006). However, the inter-subject variability in errors among the narcoleptic patients was four-fold that of the apnea patients, and 100-fold that of the controls volunteers; the variance in errors among untreated apnea patients was 27-times that of controls. The results of transformed collision data revealed main effects for group (p=0.006), time-on-task (p=0.001), and a significant interaction (p=0.022). Control subjects showed no clear evidence of increasing collision errors with time-on-task (adjusted R2=0.22), while apnea patients showed a trend toward vigilance decrement (adjusted R2=0.42, p=0.097), and narcolepsy patients evidenced a robust linear vigilance decrement (adjusted R2=0.87, p=0.004). The association of disorders of excessive somnolence with escalating time-on-task decrements makes it imperative that when assessment of neurobehavioral performance is conducted in patients, it involves task durations and analyses that will evaluate the underlying vulnerability of potentially sleepy patients to decrements over time in tasks that require sustained attention and timely responses, both of which are key components in safe driving performance.

  18. Evaluating the Relationship between Change in Performance on Training Tasks and on Untrained Outcomes

    Directory of Open Access Journals (Sweden)

    Elizabeth M Zelinski

    2014-08-01

    Full Text Available Training interventions for older adults are designed to remediate performance on trained tasks and to generalize, or transfer, to untrained tasks. Evidence for transfer is typically based on the trained group showing greater improvement than controls on untrained tasks, or on a correlation between gains in training and in transfer tasks. However, this ignores potential correlational relationships between trained and untrained tasks that exist before training. By accounting for crossed (trained and untrained and lagged (pretraining and posttraining and cross-lagged relationships between trained and untrained scores in structural equation models, the training-transfer gain relationship can be independently estimated. Transfer is confirmed if only the trained but not control participants’ gain correlation is significant. Modeling data from the Improvement in Memory with Plasticity-based Adaptive Cognitive Training (IMPACT study (Smith, et al., 2009, transfer from speeded auditory discrimination and syllable span to list and text memory and to working memory was demonstrated in 487 adults aged 65-93. Evaluation of age, sex, and education on pretest scores and on change did not alter this. The overlap of the training with transfer measures was also investigated to evaluate the hypothesis that performance gains in a nonverbal speeded auditory discrimination task may be associated with gains on fewer tasks than gains in a verbal working memory task. Gains in speeded processing were associated with gains on one list memory measure. Syllable span gains were associated with improvement in difficult list recall, story recall, and working memory factor scores. Findings confirmed that more overlap with task demands was associated with gains to more of the tasks assessed, suggesting that transfer effects are related to task overlap in multimodal training.

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

    Science.gov (United States)

    Cardis, Marco; Casadio, Maura; Ranganathan, Rajiv

    2017-09-27

    Motor variability plays an important role in motor learning, although the exact mechanisms of how variability affects learning is 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). Here 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 towards 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 to 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. Copyright © 2017, Journal of Neurophysiology.

  20. THE EFFECTS OF SEX, TOPOLOGICAL STRUCTURE, AND TASK TYPE ON HYPERTEXT NAVIGATIONAL PERFORMANCE.

    Science.gov (United States)

    Chang, Wen-Te; Chien, Yu-Hung

    2015-06-01

    Currently, almost all online materials use hyperlinks to provide users access to background, supplemental, or alternative information presented in context, greatly increasing the potential integration of information. However, a major problem is that people do not navigate hyperlinks effectively when the links become more topologically complex. Thus, identification of the variables that lead to navigational errors is necessary for the effective design of hyperlinks. Ninety-one participants (45 women, 46 men) were recruited for this experiment. All were college students and ranged in age from 19 to 23 yr. (M = 20.87, SD = 1.02). Navigational performance was examined in relation to sex, topological structure, and task type. A network topology with single-node task was superior to one with a linear topology under a single-node task condition, but equal to one with a linear topology under a multi-node task condition. Men navigated the linear topology with multi-node task and a network topology with a single-node task significantly faster than women, whereas no significant differences were observed under the other conditions. Sex interacted with topological structure and task type. This study extended the research in this domain by demonstrating an interactive effect among sex, topological structure, and task type on the navigational performance of users and can contribute to research regarding web page design.

  1. Central as well as peripheral attentional bottlenecks in dual-task performance activate lateral prefrontal cortices

    Directory of Open Access Journals (Sweden)

    Andre J Szameitat

    2016-03-01

    Full Text Available Human information processing suffers from severe limitations in parallel processing. In particular, when required to respond to two stimuli in rapid succession, processing bottlenecks may appear at central and peripheral stages of task processing. Importantly, it has been suggested that executive functions are needed to resolve the interference arising at such bottlenecks. The aims of the present study were to test whether central attentional limitations (i.e., bottleneck at the decisional response selection stage as well as peripheral limitations (i.e., bottleneck at response initiation both demand executive functions located in the lateral prefrontal cortex. For this, we re-analysed two previous studies, in which a total of 33 participants performed a dual-task according to the paradigm of the psychological refractory period (PRP during fMRI. In one study (N=17, the PRP task consisted of two two-choice response tasks known to suffer from a central bottleneck (CB group. In the other study (N=16, the PRP task consisted of two simple-response tasks known to suffer from a peripheral bottleneck (PB group. Both groups showed considerable dual-task costs in form of slowing of the second response in the dual-task (PRP effect. Imaging results are based on the subtraction of both single-tasks from the dual-task within each group. In the CB group, the bilateral middle frontal gyri and inferior frontal gyri were activated. Higher activation in these areas was associated with lower dual-task costs. In the PB group, the right middle frontal and inferior frontal gyrus were activated. Here, higher activation was associated with higher dual-task costs. In conclusion we suggest that central and peripheral bottlenecks both demand executive functions located in lateral prefrontal cortices. Differences between the CB and PB groups with respect to the exact prefrontal areas activated and the correlational patterns suggest that the executive functions resolving

  2. The Effect of Performance-Contingent Incentives when Task Complexity is Manipulated through Instruction

    Directory of Open Access Journals (Sweden)

    Monte Wynder

    2010-12-01

    Full Text Available When, and how, performance-contingent incentives improve performance is an important question fororganisations. Empirical results have been mixed – performance-contingent incentives sometimes increaseperformance, sometimes decrease performance, and sometimes have no effect. Theorists have called forfurther research to identify the effect of various moderating variables, including knowledge and taskcomplexity. This study responds by considering the role of instruction in providing the necessary knowledgeto reduce task complexity. The results suggest that a performance-contingent penalty can be a particularlyeffective means of directing effort for a simple task. For a complex task, performance can be improvedthrough instruction. The type of instruction is important – with rule-based instruction effectively directingeffort – however principle-based instruction is necessary to facilitate problem investigation and problemsolving.

  3. 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 ca...

  4. Effect of Task Constraint on Reaching Performance in Children with Spastic Diplegic Cerebral Palsy

    Science.gov (United States)

    Ju, Yun-Huei; You, Jia-Yuan; Cherng, Rong-Ju

    2010-01-01

    The purposes of the study were to examine the effect of task constraint on the reaching performance in children with spastic cerebral palsy (CP) and to examine the correlations between the reaching performance and postural control. Eight children with CP and 16 typically developing (TD) children participated in the study. They performed a…

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

    DEFF Research Database (Denmark)

    Nielsen, Kristina Tomra; Wæhrens, Eva

    2014-01-01

    reported (figure 1 and 2) and demonstrated increased effort and/or fatigue, increased use of time, need for assistance and safety problems. 85% had AMPS ADL motor ability measures below cut-off indicating clumsiness, fatigue, increased effort, safety risk and/or need of assistance during ADL task...... on self-report and observation to some extent provide similar information related to quality of ADL task performance in adults with depression. Thus, at group level problems in terms of increased physical effort and/or fatigue, inefficient use of time, some safety risk and/or need for assistance were both......Introduction Limited relationship between measures of self-reported and observed quality of ADL task performance has been revealed in a rheumatologic population, stressing the need to apply both self-report and observation in that population when evaluating ADL task performance. As occupational...

  6. The Impact of Precaution and Practice on the Performance of a Risky Motor Task

    Directory of Open Access Journals (Sweden)

    David Eilam

    2013-06-01

    Full Text Available The association between threat perception and motor execution, mediated by evolved precaution systems, often results in ritual-like behavior, including many idiosyncratic acts that seem irrelevant to the task at hand. This study tested the hypothesis that threat-detection during performance of a risky motor task would result in idiosyncratic activity that is not necessary for task completion. We asked biology students to follow a particular set of instructions in mixing three solutions labeled “bio-hazardous” and then repeat this operation with “non-hazardous” substances (or vice versa. We observed a longer duration of the overall performance, a greater repertoire of acts, longer maximal act duration, and longer mean duration of acts in the “risky” task when it was performed before the “non-risky” task. Some, but not all, of these differences were eliminated when a “non-risky” task preceded the “risky” one. The increased performance of idiosyncratic unnecessary activity is in accordance with the working hypothesis of the present study: ritualized idiosyncratic activities are performed in response to a real or illusionary threat, as a means to alleviate anxiety.

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

    Science.gov (United States)

    File, S E

    1992-01-01

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

  8. Signal detection theory and methods for evaluating human performance in decision tasks

    Science.gov (United States)

    Obrien, Kevin; Feldman, Evan M.

    1993-01-01

    Signal Detection Theory (SDT) can be used to assess decision making performance in tasks that are not commonly thought of as perceptual. SDT takes into account both the sensitivity and biases in responding when explaining the detection of external events. In the standard SDT tasks, stimuli are selected in order to reveal the sensory capabilities of the observer. SDT can also be used to describe performance when decisions must be made as to the classification of easily and reliably sensed stimuli. Numbers are stimuli that are minimally affected by sensory processing and can belong to meaningful categories that overlap. Multiple studies have shown that the task of categorizing numbers from overlapping normal distributions produces performance predictable by SDT. These findings are particularly interesting in view of the similarity between the task of the categorizing numbers and that of determining the status of a mechanical system based on numerical values that represent sensor readings. Examples of the use of SDT to evaluate performance in decision tasks are reviewed. The methods and assumptions of SDT are shown to be effective in the measurement, evaluation, and prediction of human performance in such tasks.

  9. Increasing optimism abolishes pain-induced impairments in executive task performance.

    Science.gov (United States)

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

    2014-02-01

    Coping with the demands of pain diminishes self-regulatory capacity and causes self-regulatory fatigue, which then leads to deteriorated executive task performance. It has been suggested that optimism can counteract the depletion of self-regulatory capacity. This study employed a 2 (optimism/no optimism)×2 (pain/no pain) between-subjects design to explore whether (1) experimentally induced pain (cold pressor task) deteriorates subsequent executive task performance, and (2) whether an optimism induction can counteract this sustained deteriorating effect of pain on executive task performance. Results indicated that although pain led to significantly worse performance on the executive functioning task in the no optimism condition, this sustained deteriorating effect of pain on task performance was abolished in the optimism condition. This finding is imperative because it suggests that optimism may be an important factor to implement in current psychological treatment approaches to diminish the negative impact of chronic pain on the ability to function in daily life.

  10. Effects of Local-Lag Mechanism on Task Performance in a Desktop CVE System

    Institute of Scientific and Technical Information of China (English)

    Hong Chen; Ling Chen; Gen-Cai Chen

    2005-01-01

    Consistency maintenance is a kernel problem in Collaborative Virtual Environment (CVE) research. The approaches used in Networked Virtual Environments (e.g., DR algorithm) could not be used in CVEs, for they could not prevent short-term inconsistency. Therefore, local-lag mechanism has been proposed to eliminate short-term inconsistency in CVEs. Choosing a proper lag value is a key problem in local-lag mechanism. This paper studied the effects of lag value (0ms-900ms) on task performance in a desktop CVE system. Experimental results indicate that the effect of lag value on task performance is not linear. The effect could be separated into four segments by three dividing points: 150ms, 300ms and 600ms. Lag has no effect on task performance while ranging from 0ms to 150ms. From 150ms to 300ms, lag slightly affects task performance. Lag deteriorates task performance seriously while ranging from 300ms to 600ms. When lag is longer than 600ms, the task cannot be accomplished sometimes.

  11. Sex differences in verbal working memory performance emerge at very high loads of common neuroimaging tasks.

    Science.gov (United States)

    Reed, Jessica L; Gallagher, Natalie M; Sullivan, Marie; Callicott, Joseph H; Green, Adam E

    2017-04-01

    Working memory (WM) supports a broad range of intelligent cognition and has been the subject of rich cognitive and neural characterization. However, the highest ranges of WM have not been fully characterized, especially for verbal information. Tasks developed to test multiple levels of WM demand (load) currently predominate brain-based WM research. These tasks are typically used at loads that allow most healthy participants to perform well, which facilitates neuroimaging data collection. Critically, however, high performance at lower loads may obscure differences that emerge at higher loads. A key question not yet addressed at high loads concerns the effect of sex. Thoroughgoing investigation of high-load verbal WM is thus timely to test for potential hidden effects, and to provide behavioral context for effects of sex observed in WM-related brain structure and function. We tested 111 young adults, matched on genotype for the WM-associated COMT-Val(108/158)Met polymorphism, on three classic WM tasks using verbal information. Each task was tested at four WM loads, including higher loads than those used in previous studies of sex differences. All tasks loaded on a single factor, enabling comparison of verbal WM ability at a construct level. Results indicated sex effects at high loads across tasks and within each task, such that males had higher accuracy, even among groups that were matched for performance at lower loads.

  12. Performance study on touch-pens size in three screen tasks.

    Science.gov (United States)

    Wu, Fong-Gong; Luo, Shuyi

    2006-03-01

    Experiments were aimed at investigating the performance of various sizes of touch-pens. The touch-pens were of three different lengths (80, 110 and 140 mm) and four different diameters (5.5, 8, 11 and 15 mm). Three screen tasks were used for determining a reference of ideal dimensions of a pen-based product. Sixteen subjects used 12 touch-pens to perform pointing-and-clicking, writing and drawing tasks. The subjects were asked to rank their preference after each task in the test. The results showed that the length of touch-pens should be designed to extend beyond the handbreadth when gripped. A touch-pen that facilitates natural pointing-and-clicking, writing and drawing tasks each requires a suitable diameter size. However, these tasks are typically performed together, in particular, the pointing-and-clicking and writing tasks. The recommended diameter for all three combined tasks is 8 mm. This finding indicates that selecting a touch-pen with a diameter of 8 mm and a length of 100 mm or longer is suitable for all pen-based devices.

  13. Use of Performance Measures to Evaluate, Document Competence and Deterioration of Advanced Surgical Skills Exposure for Trauma (ASSET) Surgical Skills

    Science.gov (United States)

    2015-03-01

    University, Melbourne , Australia; 3USUHS Bethesda USA; 4USAF C-STARS Baltimore Background: We developed surgical technical skills assessment metrics...scene.- He was initially taken to a small community hospital without an in- house surgeon where his blood pressure was 80/50 and his heart rate was...Bethesda USA, The Alfred Hospital and Swinburne University, Melbourne , Australia • 6) THE ASSETS OF ASSET: IMPROVING SURGICAL PERFROMANCE

  14. The influence of sex differences and individual task performance on brain activation during planning.

    Science.gov (United States)

    Unterrainer, J M; Ruff, C C; Rahm, B; Kaller, C P; Spreer, J; Schwarzwald, R; Halsband, U

    2005-01-15

    Several studies have attempted to identify the neuronal basis of sex differences in cognition. However, group differences in cognitive ability rather than genuine neurocognitive differences between the sexes may account for their results. Here, we compare with functional magnetic resonance imaging the relation between gender, individual task performance, and planning-related brain activation. Men and women preselected to display identical performance scores showed a strong relation between individual task performance and activation of the right dorsolateral prefrontal and right inferior parietal cortex activation during a visuospatial planning task. No gender-specific activations were found. However, a different pattern emerged when subjects had to execute the motor responses to the problems. Better performance was associated with right dorsolateral prefrontal and right parahippocampal activations, and females exhibited a stronger right hippocampal activation than males. These findings underline that an individual's performance level rather than his or her sex largely determines the neuronal activation patterns during higher-level cognition.

  15. Quantifying warfighter performance in a target acquisition and aiming task using wireless inertial sensors.

    Science.gov (United States)

    Davidson, Steven P; Cain, Stephen M; McGinnis, Ryan S; Vitali, Rachel R; Perkins, Noel C; McLean, Scott G

    2016-09-01

    An array of inertial measurement units (IMUS) was experimentally employed to analyze warfighter performance on a target acquisition task pre/post fatigue. Eleven participants (5M/6F) repeated an exercise circuit carrying 20 kg of equipment until fatigued. IMUs secured to the sacrum, sternum, and a rifle quantified peak angular velocity magnitude (PAVM) and turn time (TT) on a target acquisition task (three aiming events with two 180° turns) within the exercise circuit. Turning performance of two turns was evaluated pre/post fatigue. Turning performance decreased with fatigue. PAVMs decreased during both turns for the sternum (p performance after fatigue. Similar methodologies can be applied to many movement tasks, including quantifying movement performance for load, fatigue, and equipment conditions.

  16. Thinking about the weather: How display salience and knowledge affect performance in a graphic inference task.

    Science.gov (United States)

    Hegarty, Mary; Canham, Matt S; Fabrikant, Sara I

    2010-01-01

    Three experiments examined how bottom-up and top-down processes interact when people view and make inferences from complex visual displays (weather maps). Bottom-up effects of display design were investigated by manipulating the relative visual salience of task-relevant and task-irrelevant information across different maps. Top-down effects of domain knowledge were investigated by examining performance and eye fixations before and after participants learned relevant meteorological principles. Map design and knowledge interacted such that salience had no effect on performance before participants learned the meteorological principles; however, after learning, participants were more accurate if they viewed maps that made task-relevant information more visually salient. Effects of display design on task performance were somewhat dissociated from effects of display design on eye fixations. The results support a model in which eye fixations are directed primarily by top-down factors (task and domain knowledge). They suggest that good display design facilitates performance not just by guiding where viewers look in a complex display but also by facilitating processing of the visual features that represent task-relevant information at a given display location. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  17. 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

  18. The effects of sleep and sleep deprivation on task-switching performance.

    Science.gov (United States)

    Couyoumdjian, Alessandro; Sdoia, Stefano; Tempesta, Daniela; Curcio, Giuseppe; Rastellini, Elisabetta; DE Gennaro, Luigi; Ferrara, Michele

    2010-03-01

    Neural systems of the prefrontal cortex (PFC) involved in executive functions are particularly vulnerable to sleep deprivation (SD). In this study, we investigated whether SD selectively affects specific components of the executive control processes involved in task-switching performance. Two different tasks are performed in rapid and random succession in this procedure, so that the to-be-executed task may change from one trial to the next (switch trial), or may be repeated (repetition trial). Task-switches are usually slower than task repetitions, giving way to the 'switch cost'. One hundred and eight university students were assigned randomly to the sleep (S) or the SD group. Each of them was tested on a task-switching paradigm before and after an experimental night (S or SD), and after one recovery night. SD impaired both task-switching accuracy and speed. A higher proportion of errors and increased switch costs after SD have been observed, compared to normal sleep. Control analyses on switch and repetition trials showed that the SD group was significantly worse only on the switch trials. The effects of SD are reverted by one night of recovery sleep. It is concluded that the ability to adjust behaviour rapidly and flexibly to changing environmental demands, which relies on the functional integrity of the PFC, is impacted negatively by sleep loss.

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

    Science.gov (United States)

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

    2017-04-01

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

  20. "Binary" and "non-binary" detection tasks: are current performance measures optimal?

    Science.gov (United States)

    Gur, David; Rockette, Howard E; Bandos, Andriy I

    2007-07-01

    We have observed that a very large fraction of responses for several detection tasks during the performance of observer studies are in the extreme ranges of lower than 11% or higher than 89% regardless of the actual presence or absence of the abnormality in question or its subjectively rated "subtleness." This observation raises questions regarding the validity and appropriateness of using multicategory rating scales for such detection tasks. Monte Carlo simulation of binary and multicategory ratings for these tasks demonstrate that the use of the former (binary) often results in a less biased and more precise summary index and hence may lead to a higher statistical power for determining differences between modalities.

  1. Still under the microscope: can a surgical aptitude test predict otolaryngology resident performance?

    Science.gov (United States)

    Moore, Eric J; Price, Daniel L; Van Abel, Kathryn M; Carlson, Matthew L

    2015-02-01

    Application to otolaryngology-head and neck surgery residency is highly competitive, and the interview process strives to select qualified applicants with a high aptitude for the specialty. Commonly employed criteria for applicant selection have failed to show correlation with proficiency during residency training. We evaluate the correlation between the results of a surgical aptitude test administered to otolaryngology resident applicants and their performance during residency. Retrospective study at an academic otolaryngology-head and neck surgery residency program. Between 2007 and 2013, 224 resident applicants participated in a previously described surgical aptitude test administered at a microvascular surgical station. The composite score and attitudinal scores for 24 consecutive residents who matched at our institution were recorded, and their residency performance was analyzed by faculty survey on a five-point scale. The composite and attitudinal scores were analyzed for correlation with residency performance score by regression analysis. Twenty-four residents were evaluated for overall quality as a clinician by eight faculty members who were blinded to the results of surgical aptitude testing. The results of these surveys showed good inter-rater reliability. Both the overall aptitude test scores and the subset attitudinal score showed reliability in predicting performance during residency training. The goal of the residency selection process is to evaluate the candidate's potential for success in residency and beyond. The results of this study suggest that a simple-to-administer clinical skills test may have predictive value for success in residency and clinician quality. 4. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  2. Using nature-based soundscapes to support task performance and mood

    OpenAIRE

    Newbold, J. W.; Luton, J.; Cox, A L; Gould, S. J. J.

    2017-01-01

    Smartphone apps that enable workers to listen to nature soundscapes are increasingly popular. There is, however, little evidence that these soundscapes have the effects that they claim to have. Previous research exploring the effect of listening to background music during tasks has shown that while such music may have a positive effect on emotional state, it can disrupt reading and memory-based tasks. This paper explores the effects of nature soundscapes on mood and performance. A diary study...

  3. Effect of postural angle on back muscle activities in aging female workers performing computer tasks

    OpenAIRE

    Kamil, Nabilla Sofia Mohd; Dawal, Siti Zawiah Md

    2015-01-01

    [Purpose] This study investigated the effects of postural angle on back muscle activity during a computer task in aging women. [Subjects] Seventeen women ≥50 years old participated. [Methods] The participants were instructed to perform computer-related tasks for 20 minutes on a workstation that simulated typical office working conditions. Back posture was measured from the measured trunk and pelvic angles. Electromyography activities were recorded simultaneously from the cervical erector spin...

  4. 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.

  5. The neurocognitive basis for impaired dual-task performance in senior fallers

    Directory of Open Access Journals (Sweden)

    Lindsay S. Nagamatsu

    2016-02-01

    Full Text Available 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 behavioural, 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. 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.

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

    Directory of Open Access Journals (Sweden)

    Grace Vincent

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

  7. Word search performance for diagnoses of equine surgical colics in free-text electronic patient records.

    Science.gov (United States)

    Estberg, L; Case, J T; Walters, R F; Cardiff, R D; Galuppo, L D

    1998-02-27

    The objectives of the current project were to: (1) identify limitations of search sensitivity and positive predictive value (PPV) for free-text surgical diagnoses included in electronic patient records maintained at the University of California, Davis, Veterinary Medical Teaching Hospital (VMTH), (2) develop procedural or programmable recommendations for removing these limitations, and (3) provide guidelines for effective search strategies for users performing aggregate searches using the VMTH clinical information system. Search sensitivity corresponds to detection sensitivity (the capacity of a search term to 'identify' a relevant document) and search PPV indicates the proportion of retrieved documents that are relevant. All horses submitted to the VMTH for a gastrointestinal (GI) disorder requiring surgical intervention in 1995 were identified using procedure codes for billing purposes and stored in the electronic patient record. Patient records and surgical reports were reviewed for causes of GI disorders, and variation in naming of these disorders. Key word searches were performed for four GI disorders, and search performance was evaluated by estimating search sensitivity and PPV. Search sensitivity ranged from 33% to 98%, and PPV ranged from 2% to 74%. The procedural recommendation that would likely have the greatest influence on minimizing these search limitations would be more uniform naming of GI disorders. This would free searchers from having to anticipate all of the exact word combinations that could be used in the relevant documents, and also minimize retrieval of irrelevant documents.

  8. Flight tests for the assessment of task performance and control activity

    Science.gov (United States)

    Pausder, H. J.; Hummes, D.

    1982-01-01

    The tests were performed with the helicopters BO 105 and UH-1D. Closely connected with tactical demands the six test pilots' task was to minimize the time and the altitude over the obstacles. The data reduction yields statistical evaluation parameters describing the control activity of the pilots and the achieved task performance. The results are shown in form of evaluation diagrams. Additionally dolphin tests with varied control strategy were performed to get more insight into the influence of control techniques. From these test results recommendations can be derived to emphasize the direct force control and to reduce the collective to pitch crosscoupling for the dolphin.

  9. Trait Anxiety Modulates Brain Activity during Performance of Verbal Fluency Tasks.

    Science.gov (United States)

    Gawda, Barbara; Szepietowska, Ewa

    2016-01-01

    Trait anxiety is thought to be associated with pathological anxiety, and a risk factor for psychiatric disorders. The present study examines the brain mechanisms associated with trait anxiety during the performing of verbal fluency tasks. The aim is to show how trait anxiety modulates executive functions as measured by verbal fluency, and to explore the link between verbal fluency and anxiety due to the putative negative biases in high-anxious individuals. Seven tasks of verbal fluency were used: letter "k," "f," verbs, "animals," "vehicles," "joy," and "fear." The results of 35 subjects (whole sample), and 17 subjects (nine men, eight women) selected from the whole sample for the low/high-anxious groups on the basis of Trait Anxiety scores were analyzed. The subjects were healthy, Polish speaking, right-handed and aged from 20 to 35 years old. fMRI (whole-brain analysis with FWE corrections) was used to show the neural signals under active participation in verbal fluency tasks. The results confirm that trait anxiety slightly modulates neural activation during the performance of verbal fluency tasks, especially in the more difficult tasks. Significant differences were found in brain activation during the performance of more complex tasks between individuals with low anxiety and those with high anxiety. Greater activation in the right hemisphere, frontal gyri, and cerebellum was found in people with low anxiety. The results reflect better integration of cognitive and affective capacities in individuals with low anxiety.

  10. Sensitivity of negative subsequent memory and task-negative effects to age and associative memory performance.

    Science.gov (United States)

    de Chastelaine, Marianne; Mattson, Julia T; Wang, Tracy H; Donley, Brian E; Rugg, Michael D

    2015-07-01

    The present fMRI experiment employed associative recognition to investigate the relationships between age and encoding-related negative subsequent memory effects and task-negative effects. Young, middle-aged and older adults (total n=136) were scanned while they made relational judgments on visually presented word pairs. In a later memory test, the participants made associative recognition judgments on studied, rearranged (items studied on different trials) and new pairs. Several regions, mostly localized to the default mode network, demonstrated negative subsequent memory effects in an across age-group analysis. All but one of these regions also demonstrated task-negative effects, although there was no correlation between the size of the respective effects. Whereas negative subsequent memory effects demonstrated a graded attenuation with age, task-negative effects declined markedly between the young and the middle-aged group, but showed no further reduction in the older group. Negative subsequent memory effects did not correlate with memory performance within any age group. By contrast, in the older group only, task-negative effects predicted later memory performance. The findings demonstrate that negative subsequent memory and task-negative effects depend on dissociable neural mechanisms and likely reflect distinct cognitive processes. The relationship between task-negative effects and memory performance in the older group might reflect the sensitivity of these effects to variations in amount of age-related neuropathology. This article is part of a Special Issue entitled SI: Memory.

  11. The effect of task complexity and task conditions on foreign language development and performance: three empirical studies

    OpenAIRE

    Sercu, L.; Wachter, L; Peters, E.; Kuiken, F.; Vedder, I.

    2006-01-01

    It has been argued that tasks constitute a valid alternative unit to sequence the language learning process, as opposed to linguistically defined syllabuses. Implementing this claim presupposes that it is possible to access the cognitive and linguistic demands of tasks, so that they can be sequenced in such a way that they optimally support and promote the L2 learning process. Knowing what demands a task will make opens up the possibility of using task design to manipulate the learner's atten...

  12. Relationships Among Lower Body Strength, Power and Performance of Functional Tasks

    Science.gov (United States)

    Ploutz-Snyder, Lori

    2010-01-01

    There is a large degree of variability among crewmembers with respect to decrements in muscle strength and power following long duration spaceflight, ranging from 0 to approx.30% reductions. The purpose of this study was to investigate the influence of varying decrements in lower body muscle strength and power (relative to body weight) on the performance of 2 occupationally relevant tasks (ladder climb and supine egress & walk). Seventeen participants with leg strength similar to US crewmembers performed a leg press power test, an isokinetic knee extension strength test and they were asked to complete the 2 functional tasks as quickly as possible. On additional test days the participants were asked to repeat the functional tasks under 3 conditions where a different external load was applied each time using a weighted suit in order to experimentally manipulate participants strength/body weight and power/body weight ratios. The weight in the suit ranged from 20-120% of body weight and was distributed in proportion to limb segment weights to minimize changes in center of gravity. The ladder task consisted of climbing 40 rungs on a ladder treadmill as fast as possible. The supine egress & walk task consisted of rising from a supine position and walking through an obstacle course. Results show a relatively linear relationship between strength/body weight and task time and power/body weight with task time such that the fastest performance times are associated with higher strength and power with about half the variance in task time is accounted for by a single variable (either strength or power). For the average person, a 20% reduction in power/body weight (from 18 to 14.4 W/kg) induces an increase (slowing) of about 10 seconds in the ladder climb task from 14 to 24 seconds (approx.70%) and a slowing of the supine egress & walk task from 14 to 21 seconds (approx.50%). Similar relationships were observed with strength/body weight and task performance. For the average

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

    Science.gov (United States)

    Schiff, Rachel; Katan, Pesia

    2014-01-01

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

  14. Does Complexity Matter? Meta-Analysis of Learner Performance in Artificial Grammar Tasks

    Directory of Open Access Journals (Sweden)

    Rachel eSchiff

    2014-09-01

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

  15. Effects of Attentional Focus and Age on Suprapostural Task Performance and Postural Control

    Science.gov (United States)

    McNevin, Nancy; Weir, Patricia; Quinn, Tiffany

    2013-01-01

    Purpose: Suprapostural task performance (manual tracking) and postural control (sway and frequency) were examined as a function of attentional focus, age, and tracking difficulty. Given the performance benefits often found under external focus conditions, it was hypothesized that external focus instructions would promote superior tracking and…

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...

  17. The Effect of Various Instructional Modes on Children's Performance of Music Concept Tasks.

    Science.gov (United States)

    Taebel, Donald K.

    The development of certain concepts of music in kindergarten, first, and second grade children was researched. Objectives of the study were: (1) To measure the effect of four instructional modes on the performance of tasks which embodied certain musical concepts; (2) To measure the performance differences between age levels; and (3) To measure and…

  18. Introducing artificial depth cues to improve task performance in ITER maintenance actions

    NARCIS (Netherlands)

    Heemskerk, C. J. M.; Eendebak, P. T.; Schropp, G. Y. R.; Hermes, H. V.; Elzendoorn, B. S. Q.; Magielsen, A. J.

    2013-01-01

    Maintenance operations on ITER tokamak components will be largely performed by remote handling. In previous work it was shown that representative maintenance tasks could be performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indica

  19. Introducing artificial depth cues to improve task performance in ITER maintenance actions

    NARCIS (Netherlands)

    Heemskerk, C.J.M.; Eendebak, P.T.; Schropp, G.Y.R.; Hermes, H.V.; Elzendoorn, B.S.Q.; Magielsen, A.J.

    2013-01-01

    Maintenance operations on ITER tokamak components will be largely performed by remote handling. In previous work it was shown that representative maintenance tasks could be performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indica

  20. Oral-Performance Language Tasks for CSL Beginners in Second Life

    Science.gov (United States)

    Lan, Yu-Ju; Kan, Yu-Hsuan; Sung, Yao-Ting; Chang, Kuo-En

    2016-01-01

    The aim of this study was to determine the effects of different types of language tasks performed in Second Life (SL) on the oral performance of beginners of Chinese as a Second Language (CSL), focusing on oral accuracy. The 30 CSL beginners who participated in this study were randomly divided into two groups (n = 15 per group), required to…

  1. Performance of children and adolescents with Asperger syndrome or high-functioning autism on advanced theory of mind tasks.

    Science.gov (United States)

    Kaland, Nils; Callesen, Kirsten; Møller-Nielsen, Annette; Mortensen, Erik Lykke; Smith, Lars

    2008-07-01

    Although a number of advanced theory of mind tasks have been developed, there is a dearth of information on whether performances on different tasks are associated. The present study examined the performance of 21 children and adolescents with diagnoses of Asperger syndrome (AS) and 20 typically developing controls on three advanced theory of mind tasks: The Eyes Task, the Strange Stories, and the Stories from Everyday Life. The participants in the clinical group demonstrated lower performance than the controls on all the three tasks. The pattern of findings, however, indicates that these tasks may share different information-processing requirements in addition to tapping different mentalizing abilities.

  2. Real-time performance modelling of a Sustained Attention to Response Task.

    Science.gov (United States)

    Larue, Grégoire S; Rakotonirainy, Andry; Pettitt, Anthony N

    2010-10-01

    Vigilance declines when exposed to highly predictable and uneventful tasks. Monotonous tasks provide little cognitive and motor stimulation and contribute to human errors. This paper aims to model and detect vigilance decline in real time through participants' reaction times during a monotonous task. A laboratory-based experiment adapting the Sustained Attention to Response Task (SART) is conducted to quantify the effect of monotony on overall performance. Relevant parameters are then used to build a model detecting hypovigilance throughout the experiment. The accuracy of different mathematical models is compared to detect in real time - minute by minute - the lapses in vigilance during the task. It is shown that monotonous tasks can lead to an average decline in performance of 45%. Furthermore, vigilance modelling enables the detection of vigilance decline through reaction times with an accuracy of 72% and a 29% false alarm rate. Bayesian models are identified as a better model to detect lapses in vigilance as compared with neural networks and generalised linear mixed models. This modelling could be used as a framework to detect vigilance decline of any human performing monotonous tasks. STATEMENT OF RELEVANCE: Existing research on monotony is largely entangled with endogenous factors such as sleep deprivation, fatigue and circadian rhythm. This paper uses a Bayesian model to assess the effects of a monotonous task on vigilance in real time. It is shown that the negative effects of monotony on the ability to sustain attention can be mathematically modelled and predicted in real time using surrogate measures, such as reaction times. This allows the modelling of vigilance fluctuations.

  3. An application-dependent framework for the recognition of high-level surgical tasks in the OR.

    Science.gov (United States)

    Lalys, Florent; Riffaud, Laurent; Bouget, David; Jannin, Pierre

    2011-01-01

    Surgical process analysis and modeling is a recent and important topic aiming at introducing a new generation of computer-assisted surgical systems. Among all of the techniques already in use for extracting data from the Operating Room, the use of image videos allows automating the surgeons' assistance without altering the surgical routine. We proposed in this paper an application-dependent framework able to automatically extract the phases of the surgery only by using microscope videos as input data and that can be adaptable to different surgical specialties. First, four distinct types of classifiers based on image processing were implemented to extract visual cues from video frames. Each of these classifiers was related to one kind of visual cue: visual cues recognizable through color were detected with a color histogram approach, for shape-oriented visual cues we trained a Haar classifier, for texture-oriented visual cues we used a bag-of-word approach with SIFT descriptors, and for all other visual cues we used a classical image classification approach including a feature extraction, selection, and a supervised classification. The extraction of this semantic vector for each video frame then permitted to classify time series using either Hidden Markov Model or Dynamic Time Warping algorithms. The framework was validated on cataract surgeries, obtaining accuracies of 95%.

  4. Ten-year audit of Lichtenstein hernioplasty under local anaesthesia performed by surgical residents

    Directory of Open Access Journals (Sweden)

    Paajanen Hannu

    2010-08-01

    Full Text Available Abstract Background To analyse in a prospective trial the long-term results of Lichtenstein hernioplasty performed by surgical trainees. Methods Training of tension-free Lichtenstein hernia operation was started in our ambulatory unit as an outpatient procedure under local anaesthesia in 1996. After performing 36 teaching operations together with residents and their supervising specialist, 281 patients were operated during 1996-2000 either by one senior consultant (n = 141 or by 12 surgical trainees (n = 140. After 10 years, 247 (88% patients were available for the long-term assessment. Results After one month postoperatively, the rate of wound infections (consultant 1.1%, residents 0.7% and hematomas (consultant 1.1%, residents 3.0% were low and not related to surgeon's training level (ns. Only 6 (2.1% clinically evident recurrences were found after 10 years: two after specialist repair and four after trainee repair (ns. Although one third of the patients reported some discomfort after 3 and 10 years, 93-95% of the patients were very satisfied with the operation, with no statistical difference between the surgeons. Conclusion Ambulatory open mesh repair under local anaesthesia was a safe operation and the long-term results were acceptable among the patients operated by surgical trainees.

  5. Investigation of Performance Task Studies Applied by Turkish Teachers for the Purpose of Consolidation and Evaluation

    Directory of Open Access Journals (Sweden)

    Ali GÖÇER

    2014-04-01

    Full Text Available The aim of this study is to provide an overview of the applications of task performance as they are used to determine the status of the development in process and acquire the senior mental, linguistic, and social skills of students in secondary school Turkish lessons. In this study which adapted action research design in qualitative research approach, the data were obtained through interviews and document analysis method. The study was conducted on a study group consisting of 13 Turkish teachers. The data were obtained using the main form of the interview as a means of data collection. Additionally, were collected as examined document that products made by the task performance of students. The data were examined with content analysis method. According to the results of the data, almost all of the teachers in the study group have implemented performance tasks in accordance with the decisions of branch and the curriculum of the course.

  6. Performance monitoring and analysis of task-based OpenMP.

    Science.gov (United States)

    Ding, Yi; Hu, Kai; Wu, Kai; Zhao, Zhenlong

    2013-01-01

    OpenMP, a typical shared memory programming paradigm, has been extensively applied in high performance computing community due to the popularity of multicore architectures in recent years. The most significant feature of the OpenMP 3.0 specification is the introduction of the task constructs to express parallelism at a much finer level of detail. This feature, however, has posed new challenges for performance monitoring and analysis. In particular, task creation is separated from its execution, causing the traditional monitoring methods to be ineffective. This paper presents a mechanism to monitor task-based OpenMP programs with interposition and proposes two demonstration graphs for performance analysis as well. The results of two experiments are discussed to evaluate the overhead of monitoring mechanism and to verify the effects of demonstration graphs using the BOTS benchmarks.

  7. Effects of acceptance-based coping on task performance and subjective stress.

    Science.gov (United States)

    Kishita, Naoko; Shimada, Hironori

    2011-03-01

    This paper examines the interactive effects of acceptance-based coping and job control on task performance, subjective stress, and perceived control. Forty-eight undergraduate and graduate students first participated in brief educational programs based on either acceptance or control coping strategies. They then participated in a 30-min high workload task under either high or low job control conditions. The results demonstrated a significant interactive effect of acceptance-based coping and job control on perceived control and task performance. No such effect was found for subjective stress. We conclude that to improve employees' perceived control and job performance, there should be an increase not only in job control through work redesign, but also in psychological acceptance.

  8. The effect of self-management strategies on improving task performance in students with learning disabilities

    Directory of Open Access Journals (Sweden)

    Leila Bahri

    2016-02-01

    Full Text Available Introduction: Behavioral self-management approach offers some promising implications for improving independent task performance in all students particularly ones with learning disabilities. The purpose of this study was to investigate the effects of self-management training on task performance in students diagnosed as learning disabled. Methods: The participants were five students with learning disabilities attending in sub-specialty psychological clinics in Tabriz, Iran. Changing criterion design as a type of single-subject design applied, and data were gathered during each baseline and treatment sessions. Results: Training in self-management strategies was conducted in 12 sessions of 45 minutes. The self-management training improved students’ task performance and increased their academic productivity and accuracy. Conclusion: Practical implications and recommendations for school psychologists, teachers, and clinicians for appropriate application of self-management strategies are discussed.

  9. 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 approach points to structural organization at the level of the interaction-such as complementary patterns straddling speech turns and interlocutors. We develop a general, quantitative method to assess lexical, prosodic, and speech/pause patterns related to the two approaches 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.

  10. Performance monitoring and analysis of task-based OpenMP.

    Directory of Open Access Journals (Sweden)

    Yi Ding

    Full Text Available OpenMP, a typical shared memory programming paradigm, has been extensively applied in high performance computing community due to the popularity of multicore architectures in recent years. The most significant feature of the OpenMP 3.0 specification is the introduction of the task constructs to express parallelism at a much finer level of detail. This feature, however, has posed new challenges for performance monitoring and analysis. In particular, task creation is separated from its execution, causing the traditional monitoring methods to be ineffective. This paper presents a mechanism to monitor task-based OpenMP programs with interposition and proposes two demonstration graphs for performance analysis as well. The results of two experiments are discussed to evaluate the overhead of monitoring mechanism and to verify the effects of demonstration graphs using the BOTS benchmarks.

  11. An evaluation of performance by older persons on a simulated telecommuting task.

    Science.gov (United States)

    Sharit, Joseph; Czaja, Sara J; Hernandez, Mario; Yang, Yulong; Perdomo, Dolores; Lewis, John E; Lee, Chin Chin; Nair, Sankaran

    2004-11-01

    Telecommuting work represents a strategy for managing the growing number of older people in the workforce. This study involved a simulated customer service telecommuting task that used e-mail to answer customer queries about media-related products and company policies. Participants included 27 "younger" older adults (50-65 years) and 25 "older" older adults (66-80 years). The participants performed the task for two 2-hr sessions a day over 4 consecutive days. Although both age groups showed significant improvement across sessions on many of the performance criteria, in general the improvements were more marked for the older age-group participants. However, the participants from both age groups had difficulty meeting some of the task performance requirements. These results are discussed in terms of training strategies for older workers.

  12. How tree shrews (Tupaia belangeri) perform in a searching task: evidence for strategy use.

    Science.gov (United States)

    Bartolomucci, A; de Biurrun, G; Fuchs, E

    2001-12-01

    This study investigated how male tree shrews (Tupaia belangen) performed in a searching task while in their home cages and assessed whether different food distributions affected their performance. The animals were faced with a holeboard containing 9 food sources arranged in a 3 x 3 matrix or in 3 clusters, each containing 3 sources. Animals tended to start and end the trials from preferred locations, thereafter solving the task by strategically organizing the reward collection according to a minimum-distance principle. In the cluster configuration, they visited the sources hierarchically. Food distribution did not affect the performance. Comparison with data from mice and capuchin monkeys revealed that tree shrews and capuchins solved the task in a similar strategic way, whereas mice did not. These findings attract particular attention because of the phylogenetic position of tree shrews, which are regarded as closely related to primates.

  13. 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

  14. Sources of performance on theory of mind tasks in right hemisphere-damaged patients.

    Science.gov (United States)

    Surian, L; Siegal, M

    2001-08-01

    Patients with right hemisphere (RHD) or left hemisphere brain damage (LHD) were tested on Theory of Mind (ToM) tasks presented with visual aids that illustrated the relevant premises. As a measure of pragmatic ability, patients were also asked to judge replies in conversation that violated Gricean maxims. Both RHD and LHD patients performed well on the ToM tasks presented with visual aids, but RHD patients displayed difficulty when the same tasks were presented only verbally. In addition, RHD patients showed reduced sensitivity to pragmatic violations. These findings point to the role of right hemisphere structures in processing information relevant to conversations. They indicate that a crucial source of RHD patients' errors in ToM tasks may involve difficulties in utterance interpretation owing to impairments of visuospatial processing required for the representation of textual information.

  15. Measuring teaching ability with the Rasch model by scaling a series of product and performance tasks.

    Science.gov (United States)

    Wilkerson, Judy R; Lang, William Steve

    2006-01-01

    Rasch measurement can provide a much needed solution to scaling teacher ability. Typically, decisions about teacher ability are based on dichotomously scored certification tests focused on knowledge of content or pedagogy. This paper presents early developmental work of a partial-credit teacher-ability scale of 42 tasks (performances and products) with 348 rated items or criteria. The tasks and criteria are aligned with national and state standards for expected teacher knowledge and skills. These tasks are being used in about two-thirds of Florida school districts and are spreading to colleges of education. Over time there will be many variations in both tasks and criteria, but here we focus on the initial system and the Rasch model as part of the plan for development of the system.

  16. Variability and Variation of L2 Grammar: A Cross-Sectional Analysis of German Learners' Performance on Two Tasks

    Science.gov (United States)

    Abrams, Zsuzsanna; Rott, Susanne

    2017-01-01

    Research on second language (L2) grammar in task-based language learning has yielded inconsistent results regarding the effects of task-complexity, prompting calls for more nuanced analyses of L2 development and task performance. The present cross-sectional study contributes to this discussion by comparing the performance of 245 learners of German…

  17. Worms under cover: relationships between performance in learning tasks and personality in great tits (Parus major).

    Science.gov (United States)

    Amy, Mathieu; van Oers, Kees; Naguib, Marc

    2012-09-01

    In animals, individual differences in learning ability are common and are in part explained by genetic differences, developmental conditions and by general experience. Yet, not all variations in learning are well understood. Individual differences in learning may be associated with elementary individual characteristics that are consistent across situations and over time, commonly referred to as personality or temperament. Here, we tested whether or not male great tits (Parus major) from two selection lines for fast or slow exploratory behaviour, an operational measure for avian personality, vary in their learning performance in two related consecutive tasks. In the first task, birds had to associate a colour with a reward whereas in the second task, they had to associate a new colour with a reward ignoring the previously rewarded colour. Slow explorers had shorter latencies to approach the experimental device compared with fast explorers in both tasks, but birds from the two selection lines did not differ in accomplishing the first task, that is, to associate a colour with a reward. However, in the second task, fast explorers had longer latencies to solve the trials than slow explorers. Moreover, relative to the number of trials needed to reach the learning criteria in the first task, birds from the slow selection line took more trials to associate a new colour with a reward while ignoring the previously learned association compared with birds from the fast selection line. Overall, the experiments suggest that personality in great tits is not strongly related to learning per se in such an association task, but that birds from different selection lines might express different learning strategies as birds from the different selection lines were differently affected by their previous learning performance.

  18. The effect of the external regulator's absence on children's speech use, manifested self-regulation, and task performance during learning tasks

    NARCIS (Netherlands)

    Agina, Adel M.; Agina, Adel Masaud; Kommers, Petrus A.M.; Steehouder, M.F.

    2011-01-01

    The present study was conducted to explore the effect of the absence of the external regulators on children’s use of speech (private/social), task performance, and self-regulation during learning tasks. A novel methodology was employed through a computer-based learning environment that proposed

  19. The effect of the external regulator’s absence on children’s speech use, manifested self-regulation, and task performance during learning tasks

    NARCIS (Netherlands)

    Agina, Adel M.; Kommers, Piet A.M.; Steehouder, Michael F.

    2011-01-01

    The present study was conducted to explore the effect of the absence of the external regulators on children’s use of speech (private/social), task performance, and self-regulation during learning tasks. A novel methodology was employed through a computer-based learning environment that proposed thre

  20. Training Sequences and their Effects on Task Performance and User Outcomes

    DEFF Research Database (Denmark)

    Sanford, Clive Carlton

    2007-01-01

    This article introduces the concept of information technology (IT) training sequencesand examines how sequencing of conceptual and procedural training impact IT task performance, user satisfaction and users' self-efficacy. Using assimilation theory, we develop four hypotheses related to training...... sequences. These hypotheses were then tested in a database design context using a quasi-experimental study involving student subjects. Empirical results demonstrate improved far-transfer andnear-transfer task performance and higher self-efficacy for subjects trained in the conceptual-procedural sequence vs...

  1. 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.

  2. Effects of stimulus color, pattern, and practice on sex differences in mental rotations task performance.

    Science.gov (United States)

    Alington, D E; Leaf, R C; Monaghan, J R

    1992-09-01

    Redundant color information improved performance for both sexes on the Shepard Mental Rotations Task (MRT; Shepard & Metzler, 1971). Absolute score gains for women were larger than those for men; therefore, relative improvement was greater. Substantial practice effects, also favoring women, were apparent in both studies. Study 1 showed that redundant color improved performance by 0.25 SD. Study 2 demonstrated that redundant black-and-white pattern information did not have any effect; a second visuospatial channel, redundant color, was a critical factor in improving scores of men and women on difficult mental rotations tasks.

  3. Performance indicators for quality in surgical and laboratory services at Muhimbili National Hospital (MNH) in Tanzania.

    Science.gov (United States)

    Mbembati, Naboth A; Mwangu, Mugwira; Muhondwa, Eustace P Y; Leshabari, Melkizedek M

    2008-04-01

    Muhimbili National Hospital (MNH), a teaching and national referral hospital, is undergoing major reforms to improve the quality of health care. We performed a retrospective descriptive study using a set of performance indicators for the surgical and laboratory services of MNH in years 2001 and 2002, to help monitor and evaluate the impact of reforms on the quality of health care during and after the reform process. Hospital records were reviewed and information recorded for planned and postponed operations, laboratory equipment, reagents, laboratory tests and quality assurance programmes. In the year 2001 a total of 4332 non-emergency operations were planned, 3313 operations were performed and 1019 (23.5%) operations were postponed. In the year 2002, 4301 non-emergency operations were planned, 3046 were performed and 1255 (29%) were postponed. The most common reasons for operation postponement were "time-barred", interference by emergency operations, no show of patients and inoperable anaesthetic machines. Equipment problems and supply and staff shortages together accounted for one quarter of postponements. In the laboratory, a lack of equipment prevented some tests, but quality assurance was performed for most tests. Current surgical services at MNH are inadequate; operating theatres require modern, functioning equipment and adequate supplies of consumables to provide satisfactory care.

  4. The effect of surgical approach on performance of lymphadenectomy and perioperative morbidity for radical nephroureterectomy.

    Science.gov (United States)

    Pearce, Shane M; Pariser, Joseph J; Patel, Sanjay G; Steinberg, Gary D; Shalhav, Arieh L; Smith, Norm D

    2016-03-01

    To examine the effect of surgical approach on regional lymphadenectomy (LND) performance and inpatient complications for radical nephroureterectomy (NU) using a national administrative database. The National Inpatient Sample (2009-2012) was used to identify patients who underwent NU for urothelial carcinoma. Cohorts were stratified by performance of LND. Covariates included patient demographics, comorbidity, hospital characteristics, hospital volume, performance of LND, surgical approach (open [ONU], laparoscopic [LNU], or robotic [RNU]), and complications. Multivariable logistic regression was used to identify factors associated with LND performance and complications. A weighted population of 14,059 (85%) without LND and 2,560 (15%) with LND was identified. LND was more common in RNU (27%) compared with ONU (15%) and LNU (10%) (PONU, RNU was associated with increased odds of LND performance (odds ratio [OR] = 1.9, 95% CI: [1.3-2.8]; P = 0.001), whereas LNU was associated with decreased odds of LND performance (OR = 0.6, 95% CI: [0.4-0.8]; P = 0.004). Multivariable analysis of risk factors for complications demonstrated lower odds of complications with RNU (OR = 0.6, 95% CI: [0.4-0.8]; P = 0.001), whereas performance of LND increased the risk of complications (OR = 1.3, 95% CI: [1.001-1.7]; P = 0.049). When compared with ONU, RNU increased the odds of LND performance and had a lower inpatient complication rate, whereas LNU reduced the odds of LND performance and had no significant effect on inpatient complication rates. Performance of LND was independently associated with higher inpatient complication rates. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Comparing the Predictive Value of Task Performance and Task-Specific Sensitivity During Physical Function Testing Among People With Knee Osteoarthritis.

    Science.gov (United States)

    Wideman, Timothy H; Edwards, Robert R; Finan, Patrick H; Haythornthwaite, Jennifer A; Smith, Michael T

    2016-05-01

    Study Design Cross-sectional cohort. Background Knee osteoarthritis (OA) is a leading cause of pain and mobility restriction. Past research has advocated the use of brief, functional tasks to evaluate these restrictions, such as the six-minute-walk test and the timed up-and-go test. Typically, only task performance (ie, walking distance, completion time) is used to inform clinical practice. Recent research, however, suggests that individual variance in how people feel while completing these tasks (ie, task sensitivity) might also have important clinical value. Objective To compare the predictive value of task performance and task-specific sensitivity in determining OA-related physical function (measured by the Western Ontario and McMaster Universities Osteoarthritis Index) and pain-related interference (measured by the Multidimensional Pain Inventory). Methods One hundred eight participants with chronic knee OA completed the six-minute-walk test and the timed up-and-go test, and reported levels of discomfort and affective response (mood) associated with each test. Results In separate regression models, both task performance and task-specific sensitivity predicted OA-related physical function and pain-related interference. A final regression model including all significant predictors showed that task-specific sensitivity (specifically, post-six-minute-walk discomfort) emerged as a unique predictor of both outcomes. Conclusion These findings highlight the value of a novel clinical assessment strategy for patients with knee OA. While clinicians commonly focus on how patients perform on standardized functional tasks, these results highlight the value of also considering levels of posttask sensitivity. Measures of task-specific sensitivity relate to Maitland's concept of pain irritability, which may be a useful framework for future research on sensitizing factors and pain-related disability. J Orthop Sports Phys Ther 2016;46(5):346-356. Epub 21 Mar 2016. doi:10

  6. Conjoint influence of mind-wandering and sleepiness on task performance.

    Science.gov (United States)

    Stawarczyk, David; D'Argembeau, Arnaud

    2016-10-01

    Recent research suggests that sleepiness and mind-wandering-the experience of thoughts that are both stimulus-independent and task-unrelated-frequently co-occur and are both associated with poorer cognitive functioning. Whether these two phenomena have distinguishable effects on task performance remains unknown, however. To investigate this question, we used the online experience sampling of mind-wandering episodes and subjective sleepiness during a laboratory task (the Sustained Attention to Response Task; SART), and also assessed mind-wandering frequency and sleep-related disturbances in daily life using self-report questionnaires. The results revealed that the tendency to experience mind-wandering episodes during the SART and daily life was associated with higher levels of daytime sleepiness and sleep-related disturbances. More important, however, mind-wandering and sleepiness were independent predictors of SART performance at both the within- and between-individuals levels. These findings demonstrate that, although mind-wandering and sleepiness frequently co-occur, these two phenomena have distinguishable and additive effects on task performance. (PsycINFO Database Record

  7. Sex differences in spatial task performance of patients with and without unilateral cerebral lesions.

    Science.gov (United States)

    Lewis, R S; Kamptner, N L

    1987-04-01

    Two visuospatial tasks, the WAIS Block Design and the Street Gestalt Completion Test, were administered to men and women with and without unilateral cerebral lesions. These two tasks represent different categories of visuospatial functions. The Street test is a visual-perceptual gestalt task, requiring the closure of fragmented pictures, whereas Block Design is an analytical, manipulospatial task requiring rotation of spatial coordinates. For the non-brain-damaged group, the men showed a nonsignificant trend toward better Block Design performance relative to the women, whereas there was no sex-related difference in Street performance. For the brain-damaged groups, patients with right hemisphere lesions performed significantly worse than patients with left hemisphere lesions on both the Street test and Block Design, indicating that both tasks were more sensitive to right hemisphere functioning. There was, however, a significant sex X side of lesion interaction on Block Design only, with the men showing a more asymmetrical pattern of scores. These results suggest that sex differences in functional lateralization may underlie sex differences in visuospatial ability, and that sex differences in functional lateralization may be present for only certain visuospatial processes.

  8. An investigation on task-technology fit of mobile nursing information systems for nursing performance.

    Science.gov (United States)

    Hsiao, Ju-Ling; Chen, Rai-Fu

    2012-05-01

    This study investigates factors affecting the fit between nursing tasks and mobile nursing information systems and the relationships between the task-technology fit of mobile nursing information systems and nurse performance from the perspective of task-technology fit. Survey research recruited nursing staffs as subjects from selected case hospital. A total of 310 questionnaires were sent out, and 219 copies were obtained, indicating a valid response rate of 70.6%. Collected data were analyzed using the structural equation modeling technique. Our study found that dependence tasks have positive effects on information acquisition (γ=0.234, Pmobile nursing information systems in assisting nursing practices can help facilitate both independent and dependent nursing tasks. Our study discovered that the supporting functions of mobile nursing information systems have positive effects on information integration and interpretation (γ=0.365, Pmobile nursing information systems have positive effects on information acquisition (γ=0.318, Pmobile nursing information systems have positive effects on nursing performance, indicating 83.2% of totally explained variance. As shown, the use of mobile nursing information systems could provide nursing staffs with real-time and accurate information to increase efficiency and effectiveness in patient-care duties, further improving nursing performance.

  9. Cycling in the Absence of Task-related Feedback: Effects on Pacing and Performance

    Directory of Open Access Journals (Sweden)

    Benjamin Smits

    2016-08-01

    Full Text Available Introduction. To achieve personal goals in exercise task completion, exercisers have to regulate, distribute and manage their effort. In endurance sports, it has become very commonplace for athletes to consult task-related feedback on external devices to do so. The aim of the present study was to explore the importance of the presence of this information by examining the influence of the absence of commonly available task-related feedback on effort distribution and performance in experienced endurance athletes.Methods. A 20-km cycling time trial was performed. 20 Participants from a homogenous cyclist population were appointed to a group that did not receive any feedback (NoF, or a group that could consult task-related feedback (i.e., speed, heart rate, power output, cadence, elapsed time and elapsed distance continuously during their trial (FF.Results. The distribution of power output (PO differed between groups. Most evident is the spurt at the end of the trial of FF, which was not incorporated by NoF. Nevertheless, no between-group differences were found in performance time (FF: 28.86 +/- 3.68 min vs. NoF: 30.95 +/- 2.77 min and mean PO controlled by body mass (FF: 3.61 +/- .60 W/kg vs. NoF: 3.43 +/- .38 W/kg. Also, no differences in rating of perceived exertion scores were found.Conclusion. The current study provides a first indication that prior knowledge of task demands together with reliance on bodily and environmental information can be sufficient for experienced athletes to come to comparable time trial performances. This questions the necessity of the presence of in-race instantaneous task-related feedback via external devices for maximising performance. Moreover, it seems that different pacing strategies emerge depending on sources of information available to experienced athletes.

  10. 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

  11. The relationship between task conflict, task performance and team member satisfaction: the mediating role of relationship conflict

    OpenAIRE

    Hansen, Rebecca

    2015-01-01

    Task conflict and its potential positive effect on team outcomes has been questioned over the years. The findings have been inconsistent, with different studies indicating that task conflict can be positively related, negatively related or unrelated to measures of team outcomes. This study is a response to the request presented in de Wit, Greer and Jehn s (2012) recent meta-analysis, to further investigate the effect relationship conflict can have on the association between task conflict and...

  12. The role of spatial abilities and age in performance in an auditory computer navigation task.

    Science.gov (United States)

    Pak, Richard; Czaja, Sara J; Sharit, Joseph; Rogers, Wendy A; Fisk, Arthur D

    2006-01-01

    Age-related differences in spatial ability have been suggested as a mediator of age-related differences in computer-based task performance. However, the vast majority of tasks studied have primarily used a visual display (e.g., graphical user interfaces). In the current study, the relationship between spatial ability and performance in a non-visual computer-based navigation task was examined in a sample of 196 participants ranging in age from 18 to 91. Participants called into a simulated interactive voice response system and carried out a variety of transactions. They also completed measures of attention, working memory, and spatial abilities. The results showed that age-related differences in spatial ability predicted a significant amount of variance in performance in the non-visual computer task, even after controlling for other abilities. Understanding the abilities that influence performance with technology may provide insight into the source of age-related performance differences in the successful use of technology.

  13. Combined effects of attention and motivation on visual task performance: transient and sustained motivational effects

    Directory of Open Access Journals (Sweden)

    Jan B Engelmann

    2009-03-01

    Full Text Available We investigated how the brain integrates motivational and attentional signals by using a neuroimaging paradigm that provided separate estimates for transient cue- and target-related signals, in addition to sustained block-related responses. Participants performed a Posner-type task in which an endogenous cue predicted target location on 70% of trials, while motivation was manipulated by varying magnitude and valence of a cash incentive linked to task performance. Our findings revealed increased detection performance (d’ as a function of incentive value. In parallel, brain signals revealed that increases in absolute incentive magnitude led to cue- and target-specific response modulations that were independent of sustained state effects across visual cortex, fronto-parietal regions, and subcortical regions. Interestingly, state-like effects of incentive were observed in several of these brain regions, too, suggesting that both transient and sustained fMRI signals may contribute to task performance. For both cue and block periods, the effects of administering incentives were correlated with individual trait measures of reward sensitivity. Taken together, our findings support the notion that motivation improves behavioral performance in a demanding attention task by enhancing evoked responses across a distributed set of anatomical sites, many of which have been previously implicated in attentional processing. However, the effect of motivation was not simply additive as the impact of absolute incentive was greater during invalid than valid trials in several brain regions, possibly because motivation had a larger effect on reorienting than orienting attentional mechanisms at these sites.

  14. A methodological note on evaluating performance in a sustained-attention-to-response task.

    Science.gov (United States)

    Seli, Paul; Jonker, Tanya R; Solman, Grayden J F; Cheyne, James Allan; Smilek, Daniel

    2013-06-01

    We evaluated the influence of speed-accuracy trade-offs on performance in the sustained attention to response task (SART), a task often used to evaluate the effectiveness of techniques designed to improve sustained attention. In the present study, we experimentally manipulated response delay in a variation of the SART and found that commission errors, which are commonly used as an index of lapses in sustained attention, were a systematic function of manipulated differences in response delay. Delaying responses to roughly 800 ms after stimulus onset reduced commission errors substantially. We suggest the possibility that any technique that affects response speed will indirectly alter error rates independently of improvements in sustained attention. Investigators therefore need to carefully explore, report, and correct for changes in response speed that accompany improvements in performance or, alternatively, to employ tasks that control for response speed.

  15. Equation-Free Multiscale Computation enabling microscopic simulators to perform system-level tasks

    CERN Document Server

    Kevrekidis, Yu G; Hyman, J M; Kevrekidis, P G; Runborg, O; Theodoropoulos, C; Kevrekidis, Ioannis G.; Hyman, James M.; Kevrekidis, Panagiotis G.; Runborg, Olof; Theodoropoulos, Constantinos

    2002-01-01

    We present and discuss a framework for computer-aided multiscale analysis, which enables models at a "fine" (microscopic/stochastic) level of description to perform modeling tasks at a "coarse" (macroscopic, systems) level. These macroscopic modeling tasks, yielding information over long time and large space scales, are accomplished through appropriately initialized calls to the microscopic simulator for only short times and small spatial domains. Our equation-free (EF) approach, when successful, can bypass the derivation of the macroscopic evolution equations when these equations conceptually exist but are not available in closed form. We discuss how the mathematics-assisted development of a computational superstructure may enable alternative descriptions of the problem physics (e.g. Lattice Boltzmann (LB), kinetic Monte Carlo (KMC) or Molecular Dynamics (MD) microscopic simulators, executed over relatively short time and space scales) to perform systems level tasks (integration over relatively large time an...

  16. Climate uniformity: its influence on team communication quality, task conflict, and team performance.

    Science.gov (United States)

    González-Romá, Vicente; Hernández, Ana

    2014-11-01

    We investigated whether climate uniformity (the pattern of climate perceptions of organizational support within the team) is related to task conflict, team communication quality, and team performance. We used a sample composed of 141 bank branches and collected data at 3 time points. The results obtained showed that, after controlling for aggregate team climate, climate strength, and their interaction, a type of nonuniform climate pattern (weak dissimilarity) was directly related to task conflict and team communication quality. Teams with weak dissimilarity nonuniform patterns tended to show higher levels of task conflict and lower levels of team communication quality than teams with uniform climate patterns. The relationship between weak dissimilarity patterns and team performance was fully mediated by team communication quality. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  17. Medical student clerkship performance and career selection after a junior medical student surgical mentorship program.

    Science.gov (United States)

    Day, K M; Schwartz, T M; Rao, V; Khokhar, M T; Miner, T J; Harrington, D T; Ryder, B A

    2016-02-01

    The impact of early medical school mentorship in students' clerkships performance and career selection is unknown. We administered Introduction to Surgery, a resident-directed, semester-long, preclinical elective to junior medical students who answered a Likert-type survey after residency application. Elective participants (EPs) were compared with nonparticipant applicants (EAs), medical school class (MS), and national match outcomes (USA). All 18 EPs (7 M1's, 11 M2's) completed the elective and survey. EP reported more confidence and improved surgical skills, especially attributed to resident mentorship (F(13,237) = 2.3, P = 8*10(-3)). EP "honored" the clerkship more than MS (P = .05); 55.6% of EP, 37.5% of EA, and 27.7% of MS chose surgical fields, yielding a relative risk of 2.0 for EP vs MS (95% confidence interval: 1.3 to 3.2, P = 4*10(-3)). EP "strongly agree" with future mentorship programs (4.6/5), and 1 EP reported the course to be the "main reason" for applying to general surgery. Introduction to Surgery provides a model for a multifaceted junior medical student mentorship program, which has the potential to retain interested students for surgical career selection. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. The impact of positive and negative intraoperative surgeons' leadership behaviors on surgical team performance.

    Science.gov (United States)

    Barling, Julian; Akers, Amy; Beiko, Darren

    2017-07-18

    The effects of surgeons' leadership on team performance are not well understood. The purpose of this study was to examine the simultaneous effects of transformational, passive, abusive supervision and over-controlling leadership behaviors by surgeons on surgical team performance. Trained observers attended 150 randomly selected operations at a tertiary care teaching hospital. Observers recorded instances of the four leadership behaviors enacted by the surgeon. Postoperatively, team members completed validated questionnaires rating team cohesion and collective efficacy. Multiple regression analyses were computed. Data were analyzed using the complex modeling function in MPlus. Surgeons' abusive supervision was negatively associated with psychological safety (unstandardized B = -0.352, p team performance. Significant effects only surfaced for negative leadership behaviors; transformational leadership did not positively influence team performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Utilization of central nervous system resources for preparation and performance of complex walking tasks in older adults

    Directory of Open Access Journals (Sweden)

    David J Clark

    2014-08-01

    Full Text Available IntroductionWalking in the home and community often involves performance of complex walking tasks. Understanding the control of such tasks is crucial to preserving independence and quality of life in older adults. However, very little research has been conducted in this area. Here we assess the extent to which two measures of central nervous system (CNS activity are responsive to the challenges posed by preparation and performance of complex walking tasks. Prefrontal cortical activity was measured by functional near infrared spectroscopy (fNIRS and sympathetic nervous system arousal was measured by skin conductance level (SCL.Materials and MethodsSixteen older men and women (age 77.2 ± 5.6 years with mild mobility deficits participated in this study. Participants walked at their preferred speed without distractions along an unobstructed, well-lit course (control task and also walked on the same course under five separate challenging conditions: performing a cognitive verbal fluency task (verbal task, dim lighting (dim task, carrying a tray (carry task, negotiating obstacles (obstacles task and wearing a weighted vest (vest task. Mean prefrontal activation and SCL were calculated during the preparation and performance phases of each task. Gait spatiotemporal measurements were acquired by an instrumented gait mat.ResultsPrefrontal cortical activity and SCL were elevated during the preparation phase of complex walking tasks relative to the control task. During the performance phase, prefrontal activity remained elevated to a similar level as during task preparation. In contrast, SCL continued to increase beyond the level observed during task preparation. A larger increase in prefrontal activity was found to be linked to preserved quality of gait during complex walking tasks.DiscussionThese findings indicate that availability and utilization of CNS resources are important for optimizing performance of complex walking tasks in older adults.

  20. EEG measures reveal dual-task interference in postural performance in young adults.

    Science.gov (United States)

    Little, C Elaine; Woollacott, Marjorie

    2015-01-01

    The study used a dual-task (DT) postural paradigm (two tasks performed at once) that included electroencephalography (EEG) to examine cortical interference when a visual working memory (VWM) task was paired with a postural task. The change detection task was used, as it requires storage of information without updating or manipulation and predicts VWM capacity. Ground reaction forces (GRFs) (horizontal and vertical), EMG, and EEG elements, time locked to support surface perturbations, were used to infer the active neural processes underlying the automatic control of balance in 14 young adults. A significant reduction was seen between single task (ST) and DT conditions in VWM capacity (F(1,13) = 6.175, p ERP) N1 component amplitude over the L motor (p ERP amplitude and pkcopx in DT conditions provided evidence of an interference pattern, suggesting that the two modalities shared a similar set of attentional resources. The results provide direct evidence of the competition for central processing attentional resources between the two modalities, through the reduction in amplitude of the ERP evoked by the postural perturbation.

  1. Exposure to Unsolvable Anagrams Impairs Performance on the Iowa Gambling Task

    Directory of Open Access Journals (Sweden)

    Katrin Starcke

    2017-06-01

    Full Text Available Recent research indicates that external manipulations, such as stress or mood induction, can affect decision-making abilities. In the current study, we investigated whether the exposure to an unsolvable task affected subsequent performance on the Iowa Gambling Task. Participants were randomly assigned to a condition in which they were exposed to unsolvable anagrams (n = 20, or a condition in which they worked on solvable anagrams (n = 22. Afterwards, all participants played the Iowa Gambling Task, a prominent task that measures decision making under uncertain conditions with no explicit rules for gains and losses. In this task, it is essential to process feedback from previous decisions. The results demonstrated that participants who worked on unsolvable anagrams made more disadvantageous decisions on the Iowa Gambling Task than the other participants. In addition, a significant gender effect was observed: Males who worked on unsolvable anagrams made a more disadvantageous decisions than the other male participants. Females who worked on unsolvable anagrams also made more disadvantageous decision than the other female participants, but differences were small and not significant. We conclude that the exposure to unsolvable anagrams induced the experience of uncontrollability which can elicit stress and learned helplessness. Stress and learned helplessness might have reduced the ability to learn from the given feedback, particularly in male participants. We assume that in real life, uncontrollable challenges that last longer than a single experimental manipulation can affect decision making severely, at least in males.

  2. Methylphenidate decreased the amount of glucose needed by the brain to perform a cognitive task.

    Directory of Open Access Journals (Sweden)

    Nora D Volkow

    Full Text Available The use of stimulants (methylphenidate and amphetamine as cognitive enhancers by the general public is increasing and is controversial. It is still unclear how they work or why they improve performance in some individuals but impair it in others. To test the hypothesis that stimulants enhance signal to noise ratio of neuronal activity and thereby reduce cerebral activity by increasing efficiency, we measured the effects of methylphenidate on brain glucose utilization in healthy adults. We measured brain glucose metabolism (using Positron Emission Tomography and 2-deoxy-2[18F]fluoro-D-glucose in 23 healthy adults who were tested at baseline and while performing an accuracy-controlled cognitive task (numerical calculations given with and without methylphenidate (20 mg, oral. Sixteen subjects underwent a fourth scan with methylphenidate but without cognitive stimulation. Compared to placebo methylphenidate significantly reduced the amount of glucose utilized by the brain when performing the cognitive task but methylphenidate did not affect brain metabolism when given without cognitive stimulation. Whole brain metabolism when the cognitive task was given with placebo increased 21% whereas with methylphenidate it increased 11% (50% less. This reflected both a decrease in magnitude of activation and in the regions activated by the task. Methylphenidate's reduction of the metabolic increases in regions from the default network (implicated in mind-wandering was associated with improvement in performance only in subjects who activated these regions when the cognitive task was given with placebo. These results corroborate prior findings that stimulant medications reduced the magnitude of regional activation to a task and in addition document a "focusing" of the activation. This effect may be beneficial when neuronal resources are diverted (i.e., mind-wandering or impaired (i.e., attention deficit hyperactivity disorder, but it could be detrimental when

  3. Type of learning task impacts performance and strategy selection in decision making.

    Science.gov (United States)

    Pachur, Thorsten; Olsson, Henrik

    2012-09-01

    In order to be adaptive, cognition requires knowledge about the statistical structure of the environment. We show that decision performance and the selection between cue-based and exemplar-based inference mechanisms can depend critically on how this knowledge is acquired. Two types of learning tasks are distinguished: learning by comparison, by which the decision maker learns which of two objects has a higher criterion value, and direct criterion learning, by which the decision maker learns an object's criterion value directly. In three experiments, participants were trained either with learning by comparison or with direct criterion learning and subsequently tested with paired-comparison, classification, and estimation tasks. Experiments 1 and 2 showed that although providing less information, learning by comparison led to better generalization (at test), both when generalizing to new objects and when the task format at test differed from the task format during training. Moreover, learning by comparison enabled participants to provide rather accurate continuous estimates. Computational modeling suggests that the advantage of learning by comparison is due to differences in strategy selection: whereas direct criterion learning fosters the reliance on exemplar processing, learning by comparison fosters cue-based mechanisms. The pattern in decision performance reversed when the task environment was changed from a linear (Experiments 1 and 2) to a nonlinear structure (Experiment 3), where direct criterion learning led to better decisions. Our results demonstrate the critical impact of learning conditions for the subsequent selection of decision strategies and highlight the key role of comparison processes in cognition.

  4. Household task demands for quiet and focused behavior facilitate performance by ADHD youth

    Directory of Open Access Journals (Sweden)

    Camila Guimarães Mendes

    2016-07-01

    Full Text Available ABSTRACT This study evaluated the associations among symptoms of attention-deficit/hyperactivity disorder (ADHD and of oppositional defiant disorder (ODD in children and adolescents’ performance in household tasks and assistance provided by caregivers. Parents of children from 6 to 14 years old with ADHD (n = 67 were interviewed with the Children Helping Out: Responsibilities, Expectations, and Supports (CHORES instrument. Significant correlations were found between symptoms of ODD and assistance in self-care tasks (r = −0.31; p = 0.01; symptoms of hyperactivity correlated with assistance in self-care (r = −0.30, p = 0.01; and family-care (r = −0.25, p = 0.04 tasks. Age was directly associated with the number of tasks performed by children and inversely related to the assistance provided by caregivers. A greater number of ODD symptoms resulted in more household assistance from caregivers. Characteristics of ODD symptoms, such as disobedience and hostility in the face of authority, may limit these children in accessing household tasks by their own initiative, requiring assistance from caregivers.

  5. Adaptation of task difficulty in rehabilitation exercises based on the user's motor performance and physiological responses.

    Science.gov (United States)

    Shirzad, Navid; Van der Loos, H F Machiel

    2013-06-01

    Although robot-assisted rehabilitation regimens are as effective, functionally, as conventional therapies, they still lack features to increase patients' engagement in the regimen. Providing rehabilitation tasks at a "desirable difficulty" is one of the ways to address this issue and increase the motivation of a patient to continue with the therapy program. Then the problem is to design a system that is capable of estimating the user's desirable difficulty, and ultimately, modifying the task based on this prediction. In this paper we compared the performance of three machine learning algorithms in predicting a user's desirable difficulty during a typical reaching motion rehabilitation task. Different levels of error amplification were used as different levels of task difficulty. We explored the usefulness of using participants' motor performance and physiological signals during the reaching task in prediction of their desirable difficulties. Results showed that a Neural Network approach gives higher prediction accuracy in comparison with models based on k-Nearest Neighbor and Discriminant Analysis methods.

  6. The effect of task complexity and task conditions on foreign language development and performance: three empirical studies

    NARCIS (Netherlands)

    Sercu, L.; de Wachter, L.; Peters, E.; Kuiken, F.; Vedder, I.

    2006-01-01

    It has been argued that tasks constitute a valid alternative unit to sequence the language learning process, as opposed to linguistically defined syllabuses. Implementing this claim presupposes that it is possible to access the cognitive and linguistic demands of tasks, so that they can be sequenced

  7. Effect of Assessment Task and Letter Writing Ability on Preschool Children's Spelling Performance

    Science.gov (United States)

    Puranik, Cynthia; Apel, Kenn

    2010-01-01

    The purpose of this study was to examine whether spelling performance in preschool children varied as a function of the method of assessment and letter writing ability. The authors manipulated the motoric element and memory demands of the task by having children spell single words using letter tiles, orally, and by writing. The authors also…

  8. 49 CFR 40.343 - What tasks may a service agent perform for an employer?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What tasks may a service agent perform for an employer? 40.343 Section 40.343 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Roles and Responsibilities of Service Agents § 40.343...

  9. How Are Task Reflexivity and Intercultural Sensitivity Related to the Academic Performance of MBA Students?

    Science.gov (United States)

    Lyubovnikova, Joanne; Napiersky, Uwe; Vlachopoulos, Panos

    2015-01-01

    Higher education in business school environments is increasingly focused on how to best equip students with the skills necessary for leadership in the global workplace. This paper examines the impact of two particularly important cognitive capabilities--task reflexivity and intercultural sensitivity, on academic performance in an MBA programme. It…

  10. A Bayesian Network Approach to Modeling Learning Progressions and Task Performance. CRESST Report 776

    Science.gov (United States)

    West, Patti; Rutstein, Daisy Wise; Mislevy, Robert J.; Liu, Junhui; Choi, Younyoung; Levy, Roy; Crawford, Aaron; DiCerbo, Kristen E.; Chappel, Kristina; Behrens, John T.

    2010-01-01

    A major issue in the study of learning progressions (LPs) is linking student performance on assessment tasks to the progressions. This report describes the challenges faced in making this linkage using Bayesian networks to model LPs in the field of computer networking. The ideas are illustrated with exemplar Bayesian networks built on Cisco…

  11. Inspired Carbon Dioxide During Hypoxia: Effects on Task Performance and Cerebral Oxygen Saturation

    NARCIS (Netherlands)

    Dorp, E. van; Los, M.; Dirven, P.; Sarton, E.; Valk, P.; Teppema, L.; Stienstra, R.; Dahan, A.

    2007-01-01

    Introduction: Exposure to a hypoxic environment has a deleterious effect on physiological and mental functions. We studied the effect of added inspired CO2 during artificially induced hypoxic normobaric hypoxia (oxygen saturation ∼80%) on complex task performance. Methods: In random order, 22 health

  12. 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 sour

  13. Cognitive task performance causes impaired maximum force production in human hand flexor muscles.

    Science.gov (United States)

    Bray, Steven R; Graham, Jeffrey D; Martin Ginis, Kathleen A; Hicks, Audrey L

    2012-01-01

    The purpose of this study was to investigate effects of demanding cognitive task performance on intermittent maximum voluntary muscle contraction (MVC) force production. Participants performed either a modified Stroop or control task for 22 min. After the first min and at 3-min intervals thereafter, participants rated fatigue, perceived mental exertion and performed a 4-s MVC handgrip squeeze. A mixed ANOVA showed a significant interaction, F(7, 259)=2.43, p=.02, with a significant linear reduction in MVC force production over time in the cognitively depleting condition (p=.01) and no change for controls. Ratings of perceived mental exertion, F(7, 252)=2.39, p<.05, mirrored the force production results with a greater linear increase over time in the cognitive depletion condition (p<.001) compared to controls. Findings support current views that performance of cognitively demanding tasks diminishes central nervous system resources that govern self-regulation of physical tasks requiring maximal voluntary effort. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Polarity Correspondence: A General Principle for Performance of Speeded Binary Classification Tasks

    Science.gov (United States)

    Proctor, Robert W.; Cho, Yang Seok

    2006-01-01

    Differences in performance with various stimulus-response mappings are among the most prevalent findings for binary choice reaction tasks. The authors show that perceptual or conceptual similarity is not necessary to obtain mapping effects; a type of structural similarity is sufficient. Specifically, stimulus and response alternatives are coded as…

  15. THE CAPABILITIES USING OF THREE-DIMENSIONAL MODELING SYSTEM AUTOCAD IN TEACHING TO PERFORM GRAPHICS TASKS

    Directory of Open Access Journals (Sweden)

    A. V. Krasnyuk

    2008-03-01

    Full Text Available Three-dimensional design possibilities of the AutoCAD system for performing graphic tasks are presented in the article. On the basis of the studies conducted the features of application of computer-aided design system are noted and the methods allowing to decrease considerably the quantity of errors at making the drawings are offered.

  16. In search of design principles for developing digital learning & performance support for a student design task

    NARCIS (Netherlands)

    Bollen, Lars; Van der Meij, Hans; Leemkuil, Henny; McKenney, Susan

    2016-01-01

    A digital learning and performance support environment for university student design tasks was developed. This paper describes on the design rationale, process, and the usage results to arrive at a core set of design principles for the construction of such an environment. We present a collection of

  17. In search of design principles for developing digital learning & performance support for a student design task

    NARCIS (Netherlands)

    Bollen, Lars; Meij, van der Hans; Leemkuil, Henny; McKenney, Susan

    2015-01-01

    A digital learning and performance support environment for university student design tasks was developed. This paper describes on the design rationale, process, and the usage results to arrive at a core set of design principles for the construction of such an environment. We present a collection of

  18. Vocal turn-taking patterns in groups of children performing collaborative tasks: an exploratory study

    NARCIS (Netherlands)

    Kim, Jaebok; Truong, Khiet Phuong; Charisi, Vasiliki; Zaga, Cristina; Lohse, M.; Heylen, Dirk K.J.; Evers, Vanessa

    Since children (5-9 years old) are still developing their emotional and social skills, their social interactional behaviors in small groups might differ from adults' interactional behaviors. In order to develop a robot that is able to support children performing collaborative tasks in small groups,

  19. Tower of Hanoi Disk-Transfer Task: Influences of Strategy Knowledge and Learning on Performance

    Science.gov (United States)

    Welsh, Marilyn C.; Huizinga, Mariette

    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 contributions to these individual differences, were…

  20. Performance of Children with Autism Spectrum Disorders on the Dimension-Change Card Sort Task

    Science.gov (United States)

    Dichter, Gabriel S.; Radonovich, Krestin J.; Turner-Brown, Lauren M.; Lam, Kristen S. L.; Holtzclaw, Tia N.; Bodfish, James W.

    2010-01-01

    Restricted and repetitive behaviors in autism spectrum disorders have been conceptualized to reflect impaired executive functions. In the present study, we investigated the performance of 6-17-year-old children with and without an autism spectrum disorder on a dimension-change card sort task that explicitly indicated sorting rules on every trial.…

  1. Effects of environmental enrichment on cognitive performance of pigs in a spatial holeboard discrimination task

    NARCIS (Netherlands)

    Grimberg-Henrici, C.G.E.; Vermaak, P.; Bolhuis, J.E.; Nordquist, R.E.; Staay, van der F.J.

    2016-01-01

    This study investigated the effects of environmental enrichment on the cognitive performance of female conventional farm (growing) pigs in a spatial holeboard task. Ten pairs of littermates matched for weight were used. From each litter, one piglet was randomly assigned to a barren environment; the

  2. Relations among Parental Causal Attributions and Children's Math Performance and Task Persistence

    Science.gov (United States)

    Tõeväli, Paula-Karoliina; Kikas, Eve

    2017-01-01

    The present longitudinal study examined the cross-lagged relations between parental causal attributions of children's math success to children's ability, parental help, children's math performance and task persistence. A total of 735 children, their mothers, fathers and teachers were assessed twice--at the end of the second and the third grades.…

  3. Detecting Stress Patterns Is Related to Children's Performance on Reading Tasks

    Science.gov (United States)

    Gutierrez-Palma, Nicolas; Raya-Garcia, Manuel; Palma-Reyes, Alfonso

    2009-01-01

    This paper investigates the relationship between the ability to detect changes in prosody and reading performance in Spanish. Participants were children aged 6-8 years who completed tasks involving reading words, reading pseudowords, stressing pseudowords, and reproducing pseudoword stress patterns. Results showed that the capacity to reproduce…

  4. Functional Equivalence of Imagined vs. Real Performance of an Inhibitory Task: An EEG/ERP Study

    Science.gov (United States)

    Galdo-Alvarez, Santiago; Bonilla, Fidel M.; González-Villar, Alberto J.; Carrillo-de-la-Peña, María T.

    2016-01-01

    Early neuroimaging and electrophysiological studies suggested that motor imagery recruited a different network than motor execution. However, several studies have provided evidence for the involvement of the same circuits in motor imagery tasks, in the absence of overt responses. The present study aimed to test whether imagined performance of a stop-signal task produces a similar pattern of motor-related EEG activity than that observed during real performance. To this end, mu and beta event-related desynchronization (ERD) and the Lateralized Readiness Potential (LRP) were analyzed. The study also aimed to clarify the functional significance of the Stop-N2 and Stop-P3 event-related potential (ERPs) components, which were also obtained during both real and imagined performance. The results showed a common pattern of brain electrical activity, and with a similar time course, during covert performance and overt execution of the stop-signal task: presence of LRP and Stop-P3 in the imagined condition and identical LRP onset, and similar mu and beta ERD temporal windows for both conditions. These findings suggest that a similar inhibitory network may be activated during both overt and covert execution of the task. Therefore, motor imagery may be useful to improve inhibitory skills and to develop new communicating systems for Brain-Computer Interface (BCI) devices based on inhibitory signals. PMID:27695410

  5. The Effects of Self-Esteem Success-Failure, and Self-Consciousness on Task Performance.

    Science.gov (United States)

    Brockner, Joel

    1979-01-01

    In order to reduce the negative effects on performance of low self-esteem subjects' (SEs) self-focused attention, an attempt was made to change the nature of the low SEs' self-focusing, rather than reduce their self-focusing, by providing them with success feedback from a previous task. Subjects were 60 female and 30 male undergraduate students.…

  6. Effects of environmental enrichment on cognitive performance of pigs in a spatial holeboard discrimination task

    NARCIS (Netherlands)

    Grimberg-Henrici, C.G.E.; Vermaak, P.; Bolhuis, J.E.; Nordquist, R.E.; Staay, van der F.J.

    2016-01-01

    This study investigated the effects of environmental enrichment on the cognitive performance of female conventional farm (growing) pigs in a spatial holeboard task. Ten pairs of littermates matched for weight were used. From each litter, one piglet was randomly assigned to a barren environment; the

  7. Predicting performance and situation awareness of robot operators in complex situations by unit task tests

    NARCIS (Netherlands)

    Mioch, T.; Smets, N.J.J.M.; Neerincx, M.A.

    2012-01-01

    Human-in-the-loop field tests of human-robot operations in high-demand situations provide serious constraints with respect to costs and control. A set of relatively simple unit tasks might be used to do part of the testing and to establish a benchmark for human-robot performance and situation awaren

  8. Autonomy and Task Performance: Explaining the Impact of Grades on Intrinsic Motivation

    Science.gov (United States)

    Pulfrey, Caroline; Darnon, Celine; Butera, Fabrizio

    2013-01-01

    The use of grades to motivate constitutes an unresolved theoretical controversy. In 2 experiments carried out with different age groups and academic tracks, a standard-grade condition was compared with a condition in which differential scoring engendered higher grades and with a no-grade condition. The relative power of task performance and task…

  9. 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…

  10. 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 LifeBalan

  11. The Impact of Feedback Frequency on Learning and Task Performance: Challenging the "More Is Better" Assumption

    Science.gov (United States)

    Lam, Chak Fu; DeRue, D. Scott; Karam, Elizabeth P.; Hollenbeck, John R.

    2011-01-01

    Previous research on feedback frequency suggests that more frequent feedback improves learning and task performance (Salmoni, Schmidt, & Walter, 1984). Drawing from resource allocation theory (Kanfer & Ackerman, 1989), we challenge the "more is better" assumption and propose that frequent feedback can overwhelm an individual's cognitive resource…

  12. Language Learners' Writing Task Representation and Its Effect on Written Performance in an EFL Context.

    Science.gov (United States)

    Zarei, Gholam Reza; Pourghasemian, Hossein; Jalali, Hassan

    2016-10-15

    The present study attempts to give an account of how students represent writing task in an EAP course. Further, the study is intended to discover if learners' mental representation of writing would contribute to their written performance. During a 16-week term, students were instructed to practice writing as a problem solving activity. At almost the end of the term, they were prompted to write on what they thought writing task was like and also an essay on an argumentative topic. The results revealed that students could conceptualize the instructed recursive model of writing as a process-based, multi-dimensional and integrated activity inducing self-direction and organization while holding in low regard the product view of writing. The findings also demonstrated that task representation was related to the students' writing performance, with process oriented students significantly outperforming the product-oriented ones. Also, it was found that task representation components (ideational, linguistic, textual, interpersonal) had a significant relationship with the written performance ([Formula: see text]; Sig.: 0.006). The study can have both theoretical and practical implications with regard to the factors involving the students' writing internal processes and their effects on written performance.

  13. In search of design principles for developing digital learning & performance support for a student design task

    NARCIS (Netherlands)

    Bollen, Lars; Van der Meij, Hans; Leemkuil, Henny; McKenney, Susan

    2016-01-01

    A digital learning and performance support environment for university student design tasks was developed. This paper describes on the design rationale, process, and the usage results to arrive at a core set of design principles for the construction of such an environment. We present a collection of

  14. In search of design principles for developing digital learning & performance support for a student design task

    NARCIS (Netherlands)

    Bollen, Lars; van der Meij, Hans; Leemkuil, Hendrik H.; McKenney-Jensh, Susan E.

    2015-01-01

    A digital learning and performance support environment for university student design tasks was developed. This paper describes on the design rationale, process, and the usage results to arrive at a core set of design principles for the construction of such an environment. We present a collection of

  15. How Are Task Reflexivity and Intercultural Sensitivity Related to the Academic Performance of MBA Students?

    Science.gov (United States)

    Lyubovnikova, Joanne; Napiersky, Uwe; Vlachopoulos, Panos

    2015-01-01

    Higher education in business school environments is increasingly focused on how to best equip students with the skills necessary for leadership in the global workplace. This paper examines the impact of two particularly important cognitive capabilities--task reflexivity and intercultural sensitivity, on academic performance in an MBA programme. It…

  16. 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 sour

  17. Task and person-focused leadership behaviors and team performance: A meta-analysis.

    NARCIS (Netherlands)

    Ceri-Booms, Meltem; Curseu, P.L.; Oerlemans, L.A.G.

    2017-01-01

    This paper reports the results of a meta-analytic review of the relationship between person and task oriented leader behaviors, on the one hand, and team performance, on the other hand. The results, based on 89 independent samples, show a moderate positive (ρ=.33) association between both types of l

  18. The Impact of Feedback Frequency on Learning and Task Performance: Challenging the "More Is Better" Assumption

    Science.gov (United States)

    Lam, Chak Fu; DeRue, D. Scott; Karam, Elizabeth P.; Hollenbeck, John R.

    2011-01-01

    Previous research on feedback frequency suggests that more frequent feedback improves learning and task performance (Salmoni, Schmidt, & Walter, 1984). Drawing from resource allocation theory (Kanfer & Ackerman, 1989), we challenge the "more is better" assumption and propose that frequent feedback can overwhelm an individual's cognitive resource…

  19. Functional equivalence of imagined vs. real performance of an inhibitory task: an EEG/ERP study.

    Directory of Open Access Journals (Sweden)

    Santiago Galdo-Alvarez

    2016-09-01

    Full Text Available Early neuroimaging and electrophysiological studies suggested motor imagery recruited a different network than motor execution. However, several studies have provided evidence for the involvement of the same circuits in motor imagery tasks, in the absence of overt responses. The present study aimed to test whether imagined performance of a stop-signal task produces a similar pattern of motor-related EEG activity than that observed during real performance. To this end, mu and beta event-related desynchronization (ERD and the Lateralized Readiness Potential (LRP were analyzed. The study also aimed to clarify the functional significance of the Stop-N2 and Stop-P3 ERP components, which were also obtained during both real and imagined performance. The results showed a common pattern of brain electrical activity, and with a similar time course, during covert performance and overt execution of the stop-signal task: presence of LRP and Stop-P3 in the imagined condition and identical LRP onset, and similar mu and beta ERD temporal windows for both conditions. These findings suggest that a similar inhibitory network may be activated during both overt and covert execution of the task. Therefore, motor imagery may be useful to improve inhibitory skills and to develop new communicating systems for Brain Computer Interface (BCI devices based on inhibitory signals.

  20. Assessing motor imagery using the hand rotation task: Does performance change across childhood?

    NARCIS (Netherlands)

    Butson, M.L.; Hyde, C.; Steenbergen, B.; Williams, J.

    2014-01-01

    This study examined at what age children can engage in the hand rotation task (as a measure of motor imagery); whether engagement changes across development and; the influence of age and motor skill on performance. Children were aged 5-12 years (N = 101; 52 girls), with no IQ or motor skill

  1. Predicting performance and situation awareness of robot operators in complex situations by unit task tests

    NARCIS (Netherlands)

    Mioch, T.; Smets, N.J.J.M.; Neerincx, M.A.

    2012-01-01

    Human-in-the-loop field tests of human-robot operations in high-demand situations provide serious constraints with respect to costs and control. A set of relatively simple unit tasks might be used to do part of the testing and to establish a benchmark for human-robot performance and situation awaren

  2. Effects of Violent Media on Verbal Task Performance in Gifted and General Cohort Children

    Science.gov (United States)

    Çetin, Yakup; Wai, Jonathan; Altay, Cengiz; Bushman, Brad J.

    2016-01-01

    Violent media immediately grab our attention. However, violent media also detract attention from other cues. A large body of research shows that violent media impair attention and memory, critical resources for academic performance, such as verbal tasks at school. The present study tested whether gifted children are more insulated or more…

  3. Teachers' Ability and Help Attributions and Children's Math Performance and Task Persistence

    Science.gov (United States)

    Tõeväli, Paula-Karoliina; Kikas, Eve

    2016-01-01

    The present longitudinal study examined the reciprocal relationships between teachers' causal attributions and children's math performance and task persistence. In total, 760 elementary school children and their teachers participated in this study. The children were tested in math twice, at the end of the second and third grades. At both time…

  4. Emotional reactivity and cognitive performance in aversively motivated tasks: a comparison between four rat strains

    NARCIS (Netherlands)

    Staay, van der F.J.; Schuurman, T.; Reenen, van C.G.; Korte, S.M.

    2009-01-01

    Background - Cognitive function might be affected by the subjects' emotional reactivity. We assessed whether behavior in different tests of emotional reactivity is correlated with performance in aversively motivated learning tasks, using four strains of rats generally considered to have a different

  5. The effects of physical threat on team processes during complex task performance

    NARCIS (Netherlands)

    Kamphuis, W.; Gaillard, A.W.K.; Vogelaar, A.L.W.

    2011-01-01

    Teams have become the norm for operating in dangerous and complex situations. To investigate how physical threat affects team performance, 27 threeperson teams engaged in a complex planning and problem-solving task, either under physical threat or under normal conditions. Threat consisted of the pos

  6. A meta-analysis of the impact of situationally induced achievement goals on task performance

    NARCIS (Netherlands)

    Van Yperen, Nico W.; Blaga, Monica; Postmes, Thomas

    2015-01-01

    The purpose of this research was to meta-analyze studies which experimentally induced an achieve- ment goal state to examine its causal effect on the individual’s performance at the task at hand, and to investigate the moderator effects of feedback anticipation and time pressure. The data set compri

  7. 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

  8. Examining the Relationship between Free Recall and Immediate Serial Recall: The Effect of Concurrent Task Performance

    Science.gov (United States)

    Bhatarah, Parveen; Ward, Geoff; Tan, Lydia

    2006-01-01

    In 3 experiments, participants saw lists of 16 words for free recall with or without a 6-digit immediate serial recall (ISR) task after each word. Free recall was performed under standard visual silent and spoken-aloud conditions (Experiment 1), overt rehearsal conditions (Experiment 2), and fixed rehearsal conditions (Experiment 3). The authors…

  9. Assessing motor imagery using the hand rotation task: Does performance change across childhood?

    NARCIS (Netherlands)

    Butson, M.L.; Hyde, C.; Steenbergen, B.; Williams, J.

    2014-01-01

    This study examined at what age children can engage in the hand rotation task (as a measure of motor imagery); whether engagement changes across development and; the influence of age and motor skill on performance. Children were aged 5-12years (N=101; 52 girls), with no IQ or motor skill impairment.

  10. Assessing motor imagery using the hand rotation task: Does performance change across childhood?

    NARCIS (Netherlands)

    Butson, M.L.; Hyde, C.; Steenbergen, B.; Williams, J.

    2014-01-01

    This study examined at what age children can engage in the hand rotation task (as a measure of motor imagery); whether engagement changes across development and; the influence of age and motor skill on performance. Children were aged 5-12 years (N = 101; 52 girls), with no IQ or motor skill impairme

  11. Task and person-focused leadership behaviors and team performance : A meta-analysis

    NARCIS (Netherlands)

    Ceri-Booms, Meltem; Curseu, P.L.; Oerlemans, L.A.G.

    2017-01-01

    This paper reports the results of a meta-analytic review of the relationship between person and task oriented leader behaviors, on the one hand, and team performance, on the other hand. The results, based on 89 independent samples, show a moderate positive (ρ=.33) association between both types of

  12. Implementation of a Performance Task for Developing the Value of Love of Nature

    Science.gov (United States)

    Aktepe, Vedat

    2015-01-01

    The purpose of this study is to determine the effects of the love of nature performance task on the opinions and attitudes of 4th grade primary school students at the Science and Art center towards their value of love of nature. The mixed method was used by means of both quantitative and qualitative research models. The experimental group…

  13. Interindividual Differences in Learning Performance: The Effects of Age, Intelligence, and Strategic Task Approach

    Science.gov (United States)

    Kliegel, Matthias; Altgassen, Mareike

    2006-01-01

    The present study investigated fluid and crystallized intelligence as well as strategic task approaches as potential sources of age-related differences in adult learning performance. Therefore, 45 young and 45 old adults were asked to learn pictured objects. Overall, young participants outperformed old participants in this learning test. However,…

  14. [Cortex biopotential coherence changes in men and women during performance of verbal creative task].

    Science.gov (United States)

    Tarasova, I V; Vol'f, N V; Razumnikova, O M

    2009-01-01

    Patterns of EEG coherence changes induced by performance of a verbal creative task were studied in 14 male and 13 female university students. EEG coherence was computed for six frequency bands in the range from 4 to 30 Hz. Experiment consisted of two series: in the first series, the task was performed under the instruction "to create sentences", in the second series under the instruction "to create original sentences". Independently of the instruction, coherence reactivity values (data of the experiment minus corresponding baseline data) were negative in the tetal and alpha2 ranges and positive in the beta2 range in all subjects. Sex differences related to the type of instruction were found in changes in the total reactivity values of intrahemispheric coherence (sum of intrahemispheric coherence reactivity values for the all frequency bands studied). The task performance under the instruction "to create original sentences" vs. the task performance under the instruction "to create sentences" was accompanied by changes of the right-hemispheric dominance (i.e. higher values of coherence in the right hemisphere than in the left hemisphere) to the left-hemispheric dominance in women and the opposite effect in men.

  15. Assessing motor imagery using the hand rotation task: Does performance change across childhood?

    NARCIS (Netherlands)

    Butson, M.L.; Hyde, C.; Steenbergen, B.; Williams, J.

    2014-01-01

    This study examined at what age children can engage in the hand rotation task (as a measure of motor imagery); whether engagement changes across development and; the influence of age and motor skill on performance. Children were aged 5-12years (N=101; 52 girls), with no IQ or motor skill impairment.

  16. Assessing motor imagery using the hand rotation task: Does performance change across childhood?

    NARCIS (Netherlands)

    Butson, M.L.; Hyde, C.; Steenbergen, B.; Williams, J.

    2014-01-01

    This study examined at what age children can engage in the hand rotation task (as a measure of motor imagery); whether engagement changes across development and; the influence of age and motor skill on performance. Children were aged 5-12 years (N = 101; 52 girls), with no IQ or motor skill impairme

  17. Measuring working memory is all fun and games: a four-dimensional spatial game predicts cognitive task performance.

    Science.gov (United States)

    Atkins, Sharona M; Sprenger, Amber M; Colflesh, Gregory J H; Briner, Timothy L; Buchanan, Jacob B; Chavis, Sydnee E; Chen, Sy-Yu; Iannuzzi, Gregory L; Kashtelyan, Vadim; Dowling, Eamon; Harbison, J Isaiah; Bolger, Donald J; Bunting, Michael F; Dougherty, Michael R

    2014-01-01

    We developed a novel four-dimensional spatial task called Shapebuilder and used it to predict performance on a wide variety of cognitive tasks. In six experiments, we illustrate that Shapebuilder: (1) Loads on a common factor with complex working memory (WM) span tasks and that it predicts performance on quantitative reasoning tasks and Ravens Progressive Matrices (Experiment 1), (2) Correlates well with traditional complex WM span tasks (Experiment 2), predicts performance on the conditional go/no go task (Experiment 3) and N-back (Experiment 4), and showed weak or nonsignificant correlations with the Attention Networks Task (Experiment 5), and task switching (Experiment 6). Shapebuilder shows that it exhibits minimal skew and kurtosis, and shows good reliability. We argue that Shapebuilder has many advantages over existing measures of WM, including the fact that it is largely language independent, is not prone to ceiling effects, and take less than 6 min to complete on average.

  18. Opinions of Students' Parents about Performance Task in Science and Technology Class

    Directory of Open Access Journals (Sweden)

    Cengiz TÜYSÜZ

    2010-06-01

    Full Text Available The aim of this study is to determine the students’ parents’ opinions and their confrontations problems about performance task of the alternative evaluation methods during Science and Technology courses. This new alternative evaluation method aims to remove students’ memorization in education. Performance task’ target is to make studies with their teachers, developing cognitive, sensitive, psycho-motor skills of students and revealing a product as solving problem, understanding what reads, researching. The study was applied to determine parents’ attitudes towards Science and Technology performance homework at two different Primary schools in Hatay. To examine the collected data One-Way ANOVA were used. Research results showed that parents’ have largely positive attitudes towards the performance task.

  19. A Bayesian hierarchical diffusion model decomposition of performance in Approach-Avoidance Tasks.

    Science.gov (United States)

    Krypotos, Angelos-Miltiadis; Beckers, Tom; Kindt, Merel; Wagenmakers, Eric-Jan

    2015-01-01

    Common methods for analysing response time (RT) tasks, frequently used across different disciplines of psychology, suffer from a number of limitations such as the failure to directly measure the underlying latent processes of interest and the inability to take into account the uncertainty associated with each individual's point estimate of performance. Here, we discuss a Bayesian hierarchical diffusion model and apply it to RT data. This model allows researchers to decompose performance into meaningful psychological processes and to account optimally for individual differences and commonalities, even with relatively sparse data. We highlight the advantages of the Bayesian hierarchical diffusion model decomposition by applying it to performance on Approach-Avoidance Tasks, widely used in the emotion and psychopathology literature. Model fits for two experimental data-sets demonstrate that the model performs well. The Bayesian hierarchical diffusion model overcomes important limitations of current analysis procedures and provides deeper insight in latent psychological processes of interest.

  20. Trait anxiety modulates brain activity during performance of verbal fluency tasks

    Directory of Open Access Journals (Sweden)

    Barbara eGawda

    2016-02-01

    Full Text Available Trait anxiety is thought to be associated with pathological anxiety, and a risk factor for psychiatric disorders. The present study examines the brain mechanisms associated with trait anxiety during the performing of verbal fluency tasks. The aim is to show how trait anxiety modulates executive functions as measured by verbal fluency, and to explore the link between verbal fluency and anxiety due to the putative negative biases in high-anxious individuals. Seven tasks of verbal fluency were used: letter ‘k’, ‘f’, verbs, ‘animals’, ‘vehicles’, ‘joy’ and ‘fear’. The results of 35 subjects (whole sample, and 17 subjects (9 men, 8 women selected from the whole sample for the low/high-anxious groups on the basis of Trait Anxiety scores were analyzed. The subjects were healthy, Polish speaking, right-handed and aged from 20 to 35 years old. fMRI (whole-brain analysis with FWE corrections was used to show the neural signals under active participation in verbal fluency tasks. The results confirm that trait anxiety slightly modulates neural activation during the performance of verbal fluency tasks, especially in the more difficult tasks. Significant differences were found in brain activation during the performance of more complex tasks between individuals with low anxiety and those with high anxiety. Greater activation in the right hemisphere, frontal gyri, and cerebellum was found in people with low anxiety. The results reflect better integration of cognitive and affective capacities in individuals with low anxiety.

  1. Values and attitudes related to career preference and performance in the surgical clerkship.

    Science.gov (United States)

    Linn, B S; Zeppa, R

    1982-10-01

    We investigated the values and attitudes of junior medical students in relation to career preference (particularly surgery), ward behavior, and cognitive performance in the surgical clerkship. Students choosing specialty surgery were more cynical and authoritarian than those selecting general surgery. Those choosing general surgery had more self-esteem, and along with those who selected specialty surgery, more intolerance for ambiguity than other students. None of the values or attitudes were associated with grades, but several were related to ward behavior as judged by faculty and house staff. Students who valued academic achievement more and independence and intellectualism less and those with more submissive authoritarian views and more ego strength were considered better ward performers. This raises the question of whether such values and attitudes should be reinforced in ward performance or whether such students are rated higher simply because they are less disruptive to busy ward routines.

  2. Opinions of Students' Parents about Performance Task in Science and Technology Class

    OpenAIRE

    Cengiz TÜYSÜZ; Yunus KARAKUYU; Erdal TATAR

    2010-01-01

    The aim of this study is to determine the students’ parents’ opinions and their confrontations problems about performance task of the alternative evaluation methods during Science and Technology courses. This new alternative evaluation method aims to remove students’ memorization in education. Performance task’ target is to make studies with their teachers, developing cognitive, sensitive, psycho-motor skills of students and revealing a product as solving problem, understanding what reads, re...

  3. Direction of an approaching stimulus on coincident timing performance of a ballistic striking task.

    Science.gov (United States)

    Coker, Cheryl A

    2005-06-01

    The purpose of this study was to explore the influence of stimulus direction and velocity on the coincident timing performance of a ballistic striking task. 26 subjects randomly performed 20 trials at each of two stimulus velocities (4 and 8 mph) and two striking variations (moving with an approaching stimulus or in opposition to it). Analysis indicated the direction of an approaching stimulus does not appear to influence the coincident timing of a ballistic striking action.

  4. Task Performance vs. Learning Outcomes: A Study of Tangible User Interface in Classroom Setting

    OpenAIRE

    Do-Lenh, Son; Jermann, Patrick; Cuendet, Sébastien; Zufferey, Guillaume; Dillenbourg, Pierre

    2010-01-01

    Tangible User Interfaces (TUIs) offer the potential to facilitate collaborative learning in new ways. This paper presents an empirical study that investigated the effects of a TUE in a classroom setting on task performance and learning outcomes. In the tangible condition, apprentices worked together around an interactive tabletop warehouse simulation using tangible inputs. In the paper condition, they performed the same activity with only paper and pens. Results showed that the tangible condi...

  5. Evaluating the subject-performed task effect in healthy older adults: relationship with neuropsychological tests

    Directory of Open Access Journals (Sweden)

    Ana Rita Silva

    2015-04-01

    Full Text Available Background: An enhancement in recall of simple instructions is found when actions are performed in comparison to when they are verbally presented – the subject-performed task (SPT effect. This enhancement has also been found with older adults. However, the reason why older adults, known to present a deficit in episodic memory, have a better performance for this type of information remains unclear. In this article, we explored this effect by comparing the performance on the SPT task with the performance on other tasks, in order to understand the underlying mechanisms that may explain this effect. Objective: We hypothesized that both young and older adult groups should show higher recall in SPT compared with the verbal learning condition, and that the differences between age groups should be lower in the SPT condition. We aimed to explore the correlations between these tasks and known neuropsychological tests, and we also measured source memory for the encoding condition. Design: A mixed design was used with 30 healthy older adults, comparing their performance with 30 healthy younger adults. Each participant was asked to perform 16 simple instructions (SPT condition and to only read the other 16 instructions (Verbal condition – VT. The test phase included a free recall task. Participants were also tested with a set of neuropsychological measures (speed of processing, working memory and verbal episodic memory. Results: The SPT effect was found for both age groups; but even for SPT materials, group differences in recall persisted. Source memory was found to be preserved for the two groups. Simple correlations suggested differences in correlates of SPT performance between the two groups. However, when controlling for age, the SPT and VT tasks correlate with each other, and a measure of episodic memory correlated moderately with both SPT and VT performance. Conclusions: A strong effect of SPT was observed for all but one, which still displayed the

  6. Classification Systems for Individual Differences in Multiple-task Performance and Subjective Estimates of Workload

    Science.gov (United States)

    Damos, D. L.

    1984-01-01

    Human factors practitioners often are concerned with mental workload in multiple-task situations. Investigations of these situations have demonstrated repeatedly that individuals differ in their subjective estimates of workload. These differences may be attributed in part to individual differences in definitions of workload. However, after allowing for differences in the definition of workload, there are still unexplained individual differences in workload ratings. The relation between individual differences in multiple-task performance, subjective estimates of workload, information processing abilities, and the Type A personality trait were examined.

  7. Investigating sentence processing and language segmentation in explaining children's performance on a sentence-span task.

    Science.gov (United States)

    Mainela-Arnold, Elina; Misra, Maya; Miller, Carol; Poll, Gerard H; Park, Ji Sook

    2012-01-01

    Children with poor language abilities tend to perform poorly on verbal working memory tasks. This result has been interpreted as evidence that limitations in working memory capacity may interfere with the development of a mature linguistic system. However, it is possible that language abilities, such as the efficiency of sentence processing and the ability to segment language, directly influence performance on common working memory tasks. This study investigated the possible roles of sentence-processing efficiency and the ability to segment language in children's performance on a verbal working memory task. Participants were 37 children (aged 6;2-13;7) with varying oral language and reading abilities. Children completed a sentence-span task to assess working memory: the Competing Language Processing Task (CLPT). In the CLPT, children determine the truth value of sentences while maintaining sentence final words in memory. Sentence-processing efficiency was evaluated by measuring response latencies to CLPT sentence veracity judgments outside the context of the CLPT. The Elision and Blending Words subtests of the Comprehensive Test of Phonological Processing were used to measure the ability to segment and combine units of language. Children's ability to segment words into smaller units (Elision) was a significant predictor of word recall on the CLPT, which is commonly assumed to reflect working memory capacity. Sentence processing latency did not reach significance as a unique predictor. Individual differences on the sentence-span task are partly explained by the ability to segment language into smaller units. Future studies should further consider the metalinguistic and metacognitive demands of tasks used to measure working memory. If metalinguistic abilities directly impact performance on working memory tasks, the utility of working memory theories in explaining individual differences in language abilities is reduced. Inferences that link 'working memory capacity

  8. Analogy versus explicit learning of a modified basketball shooting task: performance and kinematic outcomes.

    Science.gov (United States)

    Lam, W K; Maxwell, J P; Masters, R S W

    2009-01-15

    The effects of differential instructional sets on motor skill acquisition were investigated using performance outcome and kinematic measures. Participants were provided with a single analogical instruction (analogy learning), a set of eight explicit (technical) instructions (explicit learning), or were not instructed (control). During a learning phase, participants (n=9 for each condition) performed a modified basketball shooting task over 3 days (160 trials per day). On the fourth day, participants performed a test phase consisting of two 40-trial retention tests, separated by a 40-trial secondary task transfer test, and completed a verbal protocol describing in detail the techniques that they had used to perform the task. No performance differences were found during the two retention tests, indicating similar amounts of learning for all groups. During the transfer test, performance deteriorated for both the explicit and control conditions, but not for the analogy condition. Participants in the analogy condition reported significantly fewer technical rules. Although no group differences were reported for kinematic variables, identification of movement components supported the claim that explicit learners exert conscious control over their movements, whereas analogy learners use a more implicit (unconscious or automatic) mode of movement control.

  9. Effect of intrinsic rewards on task performance of employees: Mediating role of motivation

    Directory of Open Access Journals (Sweden)

    Rizwan Qaiser Danish

    2015-02-01

    Full Text Available The basic purpose of this study was to examine the effect of reward management system, especially intrinsic rewards on task performance with the mediating role of extrinsic and intrinsic motivation of employees working in the banks in the capital of Punjab, Lahore, Pakistan. The secondary purpose of this study was to explore what level of performance these employees demonstrate towards their organizations when they are rewarded intrinsically and when they are motivated due to these reward management system accordingly. In this study, we collected data through self-administered questionnaires applying correlational explanatory research design. We distributed 300 questionnaires among which 290 were returned resulting in a response rate of 96%. The analysis of the data revealed that intrinsic rewards have positive impact on task performance of employees working in banks and motivation and its dimensions, i.e., intrinsic motivation, extrinsic motivation, and job satisfaction mediated this relationship. Considering the importance of appreciations received by bankers in the form of rewards and their effect on extra role performance and sophisticated management, policy makers should take necessary steps for improving the reward management system which will increase the task performance of employees because they will be motivated by these performance appraisal techniques.

  10. Maintaining Gait Performance by Cortical Activation during Dual-Task Interference: A Functional Near-Infrared Spectroscopy Study.

    Directory of Open Access Journals (Sweden)

    Chia-Feng Lu

    Full Text Available In daily life, mobility requires walking while performing a cognitive or upper-extremity motor task. Although previous studies have evaluated the effects of dual tasks on gait performance, few studies have evaluated cortical activation and its association with gait disturbance during dual tasks. In this study, we simultaneously assessed gait performance and cerebral oxygenation in the bilateral prefrontal cortices (PFC, premotor cortices (PMC, and supplemental motor areas (SMA, using functional near-infrared spectroscopy, in 17 young adults performing dual tasks. Each participant was evaluated while performing normal-pace walking (NW, walking while performing a cognitive task (WCT, and walking while performing a motor task (WMT. Our results indicated that the left PFC exhibited the strongest and most sustained activation during WCT, and that NW and WMT were associated with minor increases in oxygenation levels during their initial phases. We observed increased activation in channels in the SMA and PMC during WCT and WMT. Gait data indicated that WCT and WMT both caused reductions in walking speed, but these reductions resulted from differing alterations in gait properties. WCT was associated with significant changes in cadence, stride time, and stride length, whereas WMT was associated with reductions in stride length only. During dual-task activities, increased activation of the PMC and SMA correlated with declines in gait performance, indicating a control mechanism for maintaining gait performance during dual tasks. Thus, the regulatory effects of cortical activation on gait behavior enable a second task to be performed while walking.

  11. Maintaining Gait Performance by Cortical Activation during Dual-Task Interference: A Functional Near-Infrared Spectroscopy Study.

    Science.gov (United States)

    Lu, Chia-Feng; Liu, Yan-Ci; Yang, Yea-Ru; Wu, Yu-Te; Wang, Ray-Yau

    2015-01-01

    In daily life, mobility requires walking while performing a cognitive or upper-extremity motor task. Although previous studies have evaluated the effects of dual tasks on gait performance, few studies have evaluated cortical activation and its association with gait disturbance during dual tasks. In this study, we simultaneously assessed gait performance and cerebral oxygenation in the bilateral prefrontal cortices (PFC), premotor cortices (PMC), and supplemental motor areas (SMA), using functional near-infrared spectroscopy, in 17 young adults performing dual tasks. Each participant was evaluated while performing normal-pace walking (NW), walking while performing a cognitive task (WCT), and walking while performing a motor task (WMT). Our results indicated that the left PFC exhibited the strongest and most sustained activation during WCT, and that NW and WMT were associated with minor increases in oxygenation levels during their initial phases. We observed increased activation in channels in the SMA and PMC during WCT and WMT. Gait data indicated that WCT and WMT both caused reductions in walking speed, but these reductions resulted from differing alterations in gait properties. WCT was associated with significant changes in cadence, stride time, and stride length, whereas WMT was associated with reductions in stride length only. During dual-task activities, increased activation of the PMC and SMA correlated with declines in gait performance, indicating a control mechanism for maintaining gait performance during dual tasks. Thus, the regulatory effects of cortical activation on gait behavior enable a second task to be performed while walking.

  12. Mind-wandering and task stimuli: Stimulus-dependent thoughts influence performance on memory tasks and are more often past- versus future-oriented.

    Science.gov (United States)

    Maillet, David; Seli, Paul; Schacter, Daniel L

    2017-07-01

    Although many studies have indicated that participants frequently mind-wander during experimental tasks, relatively little research has examined the extent to which such thoughts are triggered by task stimuli (stimulus-dependent thoughts; SDTs) versus internally triggered (stimulus-independent thoughts; SITs). In the current experiment, we assessed differences in the frequency and characteristics of SDTs and SITs, as well as their associations with subsequent memory in young adults. Whereas frequency of SDTs (but not SITs) increased in a task with more meaningful stimuli, frequency of SITs (but not SDTs) increased in an easier task. Furthermore, only SDTs were more likely to be past- versus future-oriented. Finally, frequency and vividness of SDTs during a shallow, but not a deep, incidental encoding task both correlated with later memory performance for word stimuli. These results suggest that SDTs differ from SITs in several important ways. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. 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.

  14. An Experimental Study of Team Size and Performance on a Complex Task.

    Science.gov (United States)

    Mao, Andrew; Mason, Winter; Suri, Siddharth; Watts, Duncan J

    2016-01-01

    The relationship between team size and productivity is a question of broad relevance across economics, psychology, and management science. For complex tasks, however, where both the potential benefits and costs of coordinated work increase with the number of workers, neither theoretical arguments nor empirical evidence consistently favor larger vs. smaller teams. Experimental findings, meanwhile, have relied on small groups and highly stylized tasks, hence are hard to generalize to realistic settings. Here we narrow the gap between real-world task complexity and experimental control, reporting results from an online experiment in which 47 teams of size ranging from n = 1 to 32 collaborated on a realistic crisis mapping task. We find that individuals in teams exerted lower overall effort than independent workers, in part by allocating their effort to less demanding (and less productive) sub-tasks; however, we also find that individuals in teams collaborated more with increasing team size. Directly comparing these competing effects, we find that the largest teams outperformed an equivalent number of independent workers, suggesting that gains to collaboration dominated losses to effort. Importantly, these teams also performed comparably to a field deployment of crisis mappers, suggesting that experiments of the type described here can help solve practical problems as well as advancing the science of collective intelligence.

  15. Go/No-Go task performance predicts differences in compulsivity but not in impulsivity personality traits.

    Science.gov (United States)

    Sánchez-Kuhn, Ana; León, José Juan; Gôngora, Karinna; Pérez-Fernández, Cristian; Sánchez-Santed, Fernando; Moreno, Margarita; Flores, Pilar

    2017-11-01

    Lack of inhibitory control is present in impulsive and compulsive personality traits. The Go/No-Go task is one of the most effective means to assess response inhibition measured by the ability to appropriately withhold responding to No-Go stimuli. The aim of this work was to study whether differences in performance of Go/No-Go task predicts differences in personality traits related to inhibitory control. For this purpose 63 healthy participants divided into two groups based on the median split of false alarms on the Go/No-Go task completed Barratt Impulsiveness Scale (BIS-11) and the Maudsley Obsessional Compulsive Questionnaire (MOCI). Results showed that participants with high false alarms (H-FA) displayed a high-risk strategy of responding, and higher scores in the MOCI Total and MOCI Checking subscale compared to participants with low false alarms (L-FA). The results show for the first time a relation between the execution of the Go/No-Go task and the MOCI scale. Surprisingly, no relation was found between the Go/No-Go task and the BIS-11 scale. Further studies are needed to define the heterogeneous constructs of compulsivity and impulsivity, and to improve the convergence of the clinical scales and the behavioral measures of these two personality traits. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

    Fusaroli, Riccardo; Tylén, Kristian

    2016-01-01

    interlocutors, the synergy approach points to structural organization at the level of the interaction - such as complementary patterns straddling speech-turns and interlocutors. We develop a general, quantitative method to assess lexical, prosodic and speech/pause patterns related to the two approaches......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...

  17. The influence of time management skill on the curvilinear relationship between organizational citizenship behavior and task performance.

    Science.gov (United States)

    Rapp, Adam A; Bachrach, Daniel G; Rapp, Tammy L

    2013-07-01

    In this research we integrate resource allocation and social exchange perspectives to build and test theory focusing on the moderating role of time management skill in the nonmonotonic relationship between organizational citizenship behavior (OCB) and task performance. Results from matching survey data collected from 212 employees and 41 supervisors and from task performance metrics collected several months later indicate that the curvilinear association between OCB and task performance is significantly moderated by employees' time management skill. Implications for theory and practice are discussed.

  18. Perceived difficulty with physical tasks, lifestyle, and physical performance in obese children.

    Science.gov (United States)

    Valerio, Giuliana; Gallarato, Valeria; D'Amico, Osvaldo; Sticco, Maura; Tortorelli, Paola; Zito, Eugenio; Nugnes, Rosa; Mozzillo, Enza; Franzese, Adriana

    2014-01-01

    We estimated perceived difficulty with physical tasks, lifestyle, and physical performance in 382 children and adolescents (163 obese, 54 overweight, and 165 normal-weight subjects) and the relationship between perceived physical difficulties and sports participation, sedentary behaviors, or physical performance. Perceived difficulty with physical tasks and lifestyle habits was assessed by interview using a structured questionnaire, while physical performance was assessed through the six-minute walking test (6 MWT). Obese children had higher perceived difficulty with several activities of daily living, were less engaged in sports, and had lower physical performance than normal-weight or overweight children; on the contrary, they did not differ with regard to time spent in sedentary behaviors. Perceived difficulty in running and hopping negatively predicted sports participation (P physical activities negatively predicted the 6 MWT, independently of BMI (P children. These findings may have practical implications for approaching physical activity in obese children. Exploring both the perception of a task's difficulty level and physical performance may be useful to design exercise programs that allow safe and successful participation.

  19. Optimization procedure for algorithms of task scheduling in high performance heterogeneous distributed computing systems

    Directory of Open Access Journals (Sweden)

    Nirmeen A. Bahnasawy

    2011-11-01

    Full Text Available In distributed computing, the schedule by which tasks are assigned to processors is critical to minimizing the execution time of the application. However, the problem of discovering the schedule that gives the minimum execution time is NP-complete. In this paper, a new task scheduling algorithm called Sorted Nodes in Leveled DAG Division (SNLDD is introduced and developed for HeDCSs with consider a bounded number of processors. The main principle of the developed algorithm is to divide the Directed Acyclic Graph (DAG into levels and sort the tasks in each level according to their computation size in descending order. To evaluate the performance of the developed SNLDD algorithm, a comparative study has been done between the developed SNLDD algorithm and the Longest Dynamic Critical Path (LDCP algorithm which is considered the most efficient existing algorithm. According to the comparative results, it is found that the performance of the developed algorithm provides better performance than the LDCP algorithm in terms of speedup, efficiency, complexity, and quality. Also, a new procedure called Superior Performance Optimization Procedure (SPOP has been introduced and implemented in the developed SNLDD algorithm and the LDCP algorithm to minimize the sleek time of the processors in the system. Again, the performance of the SNLDD algorithm outperforms the existing LDCP algorithm after adding the SPOP procedure.

  20. Impact of isolated clinical performance feedback on clinical productivity of an academic surgical faculty.

    Science.gov (United States)

    Paxton, E Scott; Hamilton, Barton H; Boyd, Vivian R; Hall, Bruce L

    2006-05-01

    There is increasing financial pressure to maximize clinical productivity for academic physicians. We examined whether clinical performance feedback alone could contribute to improving the clinical productivity of surgeons in an academic department of surgery. We implemented a clinical performance feedback program in January 2003. We then compared clinical productivity in terms of relative value units (RVUs) of surgeons for 18 months before and 18 months after this intervention, using each surgeon as his or her own control. Regression was performed with dependent variable ln (monthly RVUs) and independent variables "calendar month," "pre/post" January 2003, and "surgeon." The coefficient on "pre/post" reflected average change in RVUs. We also surveyed faculty on their use of and attitudes toward this feedback. There was a 58% survey response. Ninety-two percent of responding faculty reported that they viewed and used the performance feedback, and that it affected their practice. Ninety-two percent believed the information accurately reflected their performance, 89% thought that the comparisons were useful, and 79% desired more feedback information, specifically, comparisons with external benchmarks. When RVU data were examined, the coefficient on change pre- and postintervention indicated a 7.4% increase in productivity (p increase (p=0.003) after exclusion of outliers. Performance feedback was associated with a small (6.0%) but significant improvement in productivity in this academic surgical faculty group. Performance feedback can be useful and should be used in conjunction with other management tools for this population.

  1. Hand-opening feedback for myoelectric forearm prostheses: performance in virtual grasping tasks influenced by different levels of distraction.

    Science.gov (United States)

    Witteveen, Heidi J B; de Rond, Leonie; Rietman, Johan S; Veltink, Peter H

    2012-01-01

    Sensory feedback and the required attentional demands are important aspects in prosthesis acceptance. In this study, hand-opening feedback is provided and the performance in a virtual grasping task is investigated. Simultaneously, a secondary task was performed to investigate the attentional demands. Ten nondisabled subjects performed the tasks with and without feedback about the hand opening through an array of eight vibrotactile stimulators on the forearm. Activation of one stimulator corresponded to one hand-opening position. For the dual-task experiments, subjects simultaneously performed a secondary auditory counting task. The addition of vibrotactile feedback increased the performance (expressed in percentages of correct hand positions, mean absolute errors in position, and percentages of deviations up to one hand-opening position), but the duration of the tasks was also increased. Three levels of distraction (no distraction, counting task, count and subtract task) were applied, which did not influence the performance in the grasping tasks except for the highest level of distraction. We concluded that the proposed method to provide hand-opening feedback through an array of eight vibrotactile stimulators is successful because the performance in a grasping task increases but it is not significantly attention demanding.

  2. Structural hippocampal anomalies in a schizophrenia population correlate with navigation performance on a wayfinding task

    Directory of Open Access Journals (Sweden)

    Andrée-Anne eLedoux

    2014-03-01

    Full Text Available Episodic memory, related to the hippocampus, has been found to be impaired in schizophrenia. Further, hippocampal anomalies have also been observed in schizophrenia. This study investigated whether average hippocampal grey matter (GM would differentiate performance on a hippocampus-dependent memory task in patients with schizophrenia and healthy controls. Twenty-one patients with schizophrenia and twenty-two control participants were scanned with an MRI while being tested on a wayfinding task in a virtual town (e.g., find the grocery store from the school. Regressions were performed for both groups individually and together using GM and performance on the wayfinding task. Results indicate that controls successfully completed the task more often than patients, took less time, and made fewer errors. Additionally, controls had significantly more hippocampal GM than patients. Poor performance was associated with a GM decrease in the right hippocampus for both groups. Within group regressions found an association between right hippocampi GM and performance in controls and an association between the left hippocampi GM and performance in patients. A second analysis revealed that different anatomical GM regions, known to be associated with the hippocampus, such as the parahippocampal cortex, amygdala, medial and orbital prefrontal cortices, covaried with the hippocampus in the control group. Interestingly, the cuneus and cingulate gyrus also covaried with the hippocampus in the patient group but the orbital frontal cortex did not, supporting the hypothesis of impaired connectivity between the hippocampus and the frontal cortex in schizophrenia. These results present important implications for creating intervention programs aimed at measuring functional and structural changes in the hippocampus in schizophrenia.

  3. The joint effects of personality and workplace social exchange relationships in predicting task performance and citizenship performance.

    Science.gov (United States)

    Kamdar, Dishan; Van Dyne, Linn

    2007-09-01

    This field study examines the joint effects of social exchange relationships at work (leader-member exchange and team-member exchange) and employee personality (conscientiousness and agreeableness) in predicting task performance and citizenship performance. Consistent with trait activation theory, matched data on 230 employees, their coworkers, and their supervisors demonstrated interactions in which high quality social exchange relationships weakened the positive relationships between personality and performance. Results demonstrate the benefits of consonant predictions in which predictors and outcomes are matched on the basis of specific targets. We discuss theoretical and practical implications.

  4. Dual-Task Performance as a Measure of Mental Effort in Searching a Library System and the Web

    OpenAIRE

    Kim, Yong-Mi; Rieh, Soo Young

    2005-01-01

    This paper examines a dual-task method for the assessment of mental effort during online searching, having the users engage in two tasks simultaneously. Searching was assigned as a primary task and a visual observation was set up as a secondary task. The study participants were asked to perform two searches, one on the Web and the other in a webbased library system. Perceived search difficulty and mental effort for searching on the two types of systems were compared through participa...

  5. Low Complexity Performance Effective Task Scheduling Algorithm for Heterogeneous Computing Environments

    Directory of Open Access Journals (Sweden)

    E. Ilavarasan

    2007-01-01

    Full Text Available A heterogeneous computing environment is a suite of heterogeneous processors interconnected by high-speed networks, thereby promising high speed processing of computationally intensive applications with diverse computing needs. Scheduling of an application modeled by Directed Acyclic Graph (DAG is a key issue when aiming at high performance in this kind of environment. The problem is generally addressed in terms of task scheduling, where tasks are the schedulable units of a program. The task scheduling problems have been shown to be NP-complete in general as well as several restricted cases. In this study we present a simple scheduling algorithm based on list scheduling, namely, low complexity Performance Effective Task Scheduling (PETS algorithm for heterogeneous computing systems with complexity O (e (p+ log v, which provides effective results for applications represented by DAGs. The analysis and experiments based on both randomly generated graphs and graphs of some real applications show that the PETS algorithm substantially outperforms the existing scheduling algorithms such as Heterogeneous Earliest Finish Time (HEFT, Critical-Path-On a Processor (CPOP and Levelized Min Time (LMT, in terms of schedule length ratio, speedup, efficiency, running time and frequency of best results.

  6. Sleep-related offline improvements in gross motor task performance occur under free recall requirements

    Directory of Open Access Journals (Sweden)

    Andreas eMalangre

    2016-03-01

    Full Text Available Nocturnal sleep effects on memory consolidation following gross motor sequence learning were examined using a complex arm movement task. This task required participants to produce non-regular spatial patterns in the horizontal plane by successively fitting a small peg into different target-holes on an electronic pegboard. The respective reaching movements typically differed in amplitude and direction. Targets were visualized prior to each transport movement on a computer screen. With this task we tested 18 subjects (22.6 +/- 1.9 years; 8 female using a between-subjects design. Participants initially learned a 10-element arm movement sequence either in the morning or in the evening. Performance was retested under free recall requirements 15 minutes post training, as well as 12 hrs and 24 hrs later. Thus each group was provided with one sleep-filled and one wake retention interval. Dependent variables were error rate (number of erroneous sequences and average sequence execution time (correct sequences only. Performance improved during acquisition. Error rate remained stable across retention. Sequence execution time (inverse to execution speed significantly decreased again during the sleep-filled retention intervals, but remained stable during the respective wake intervals. These results corroborate recent findings on sleep-related enhancement consolidation in ecological valid, complex gross motor tasks. At the same time they suggest this effect to be truly memory-based and independent from repeated access to extrinsic sequence information during retests.

  7. Grip type and task goal modify reach-to-grasp performance in post-stroke hemiparesis

    Science.gov (United States)

    Schaefer, Sydney Y.; DeJong, Stacey L.; Cherry, Kendra M.; Lang, Catherine E.

    2011-01-01

    This study investigated whether grip type and/or task goal influenced reaching and grasping performance in post-stroke hemiparesis. Sixteen adults with post-stroke hemiparesis and twelve healthy adults reached to and grasped a cylindrical object using one of two grip types (3-finger or palmar) to achieve one of two task goals (hold or lift). Performance of the stroke group was characteristic of hemiparetic limb movement during reach-to-grasp, with more curved handpaths and slower velocities compared to the control group. These effects were present regardless of grip type or task goal. Other measures of reaching (reach time and reach velocity at object contact) and grasping (peak thumb-index finger aperture during the reach and peak grip force during the grasp) were differentially affected by grip type, task goal, or both, despite the presence of hemiparesis, providing new evidence that changes in motor patterns after stroke may occur to compensate for stroke-related motor impairment. PMID:22357103

  8. Non motor tasks improve adaptive brain-computer interface performance in users with severe motor impairment

    Directory of Open Access Journals (Sweden)

    Josef eFaller

    2014-10-01

    Full Text Available Individuals with severe motor impairment can use event-related desynchronization (ERD based BCIs as assistive technology. Auto-calibrating and adaptive ERD-based BCIs that users control with motor imagery tasks (SMR-AdBCI have proven effective for healthy users. We aim to find an improved configuration of such an adaptive ERD-based BCI for individuals with severe motor impairment as a result of spinal cord injury (SCI or stroke. We hypothesized that an adaptive ERD-based BCI, that automatically selects a user specific class-combination from motor-related and non motor-related mental tasks during initial auto-calibration (Auto-AdBCI could allow for higher control performance than a conventional SMR-AdBCI. To answer this question we performed offline analyses on two sessions (21 data sets total of cue-guided, five-class electroencephalography (EEG data recorded from individuals with SCI or stroke. On data from the twelve individuals in Session 1, we first identified three bipolar derivations for the SMR-AdBCI. In a similar way, we determined three bipolar derivations and four mental tasks for the Auto-AdBCI. We then simulated both, the SMR-AdBCI and the Auto-AdBCI configuration on the unseen data from the nine participants in Session 2 and compared the results. On the unseen data of Session 2 from individuals with SCI or stroke, we found that automatically selecting a user specific class-combination from motor-related and non motor-related mental tasks during initial auto-calibration (Auto-AdBCI significantly (p<0.01 improved classification performance compared to an adaptive ERD-based BCI that only used motor imagery tasks (SMR-AdBCI; average accuracy of 75.7 versus 66.3%.

  9. Performance Monitoring and Response Inhibition in a Saccadic Countermanding Task in High and Low proficient bilinguals.

    Directory of Open Access Journals (Sweden)

    Niharika eSingh

    2015-01-01

    Full Text Available We compared Hindi-English bilinguals differing in their L2 fluency on a saccadic countermanding task which taps inhibitory control as well as monitoring. We particularly explored whether response inhibition and performance monitoring within the oculomotor domain are affected by language proficiency in bilinguals. There were two different oculomotor redirect tasks: Visually Guided Redirect (VGR task (Experiment1 and Memory Guided Redirect (MGR task (Experiment 2. In this task typically a target is presented to which subject must make saccade (No step trials, unless a new target appears on the other location after some delay from the first target onset (Step trials. On such trials participants are required to inhibit and cancel the saccade to the first instead program a saccade to the new target. Using trial switch reaction time (TSRT, which is the time taken to inhibit the initiated saccade to the first target, as a measure of response inhibition, and post-stop slowing as a measure of performance monitoring, we observed two important results. It was found that high proficiency bilinguals showed more post-stop slowing on the no-step trials as compared to the low proficiency bilinguals for both VGR and MGR. Secondly, high and low proficiency bilingual exhibited comparable TSRT in both VGR and MGR, showing no altering effect of language proficiency on the response inhibition in bilinguals. These results suggest that bilingualism impacts performance monitoring which is modulated by language proficiency if not the inhibitory control system. Higher fluency may lead to superior cognitive flexibility, and ability to adjust behaviour that facilitates attainment of cognitive goal. These findings are in consonance with other current studies that suggest a top-down effect of bilingualism on action control systems.

  10. Acceptable weights and physiological costs of performing combined manual handling tasks in restricted postures

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, S. (US Bureau of Mines, Pittsburgh, PA (USA). Pittsburgh Research Center)

    1991-07-01

    Eight healthy, male underground coal miners (mean age 36.9 yrs [+-]4.5 SD) participated in a study examining psychophysically acceptable weights and physiological costs of performing combined lifting and lowering in restricted headroom conditions. Independent variables included posture (stooping or kneeling on two knees), task symmetry (symmetric or asymmetric), and vertical lift distance (35 cm or 60 cm). All tasks were 10 min in duration and were performed under a 1.22 m ceiling to restrict subject's posture. Subjects were required to raise and lower a lifting box every 10s, and asked to adjust the box weight to the maximum amount they could handle without undue strain or fatigue. During the final 5 min. of each test, data were collected to determine the energy expenditure requirements of the task. Results of this study demonstrated that pyschophysical lifting capacity averaged 11.3% lower when kneeling as compared to stooping. Subjects selected 3.5% more weight in asymmetric tasks, and lifted 5.0% less weight to the 60 cm shelf compared to the 35 cm shelf. Heart rate was not significantly affected by posture, but was increased an average of 4 beats/min in asymmetric conditions, and by 3.5 beats/min while lifting/lowering to/from the high shelf. Oxygen uptake was increased by 9% when stooped, by 10% when lifting/lowering asymmetrically, and by 8.2% when performing the task to the high shelf. Results of this study indicate that, wherever possible, materials that must be lifted manually in low-seam coal mines be designed in accordance with the decreased lifting capacity exhibited in a kneeling posture. 47 refs., 1 fig., 2 tabs.

  11. Keeping it steady: older adults perform more consistently on cognitive tasks than younger adults.

    Science.gov (United States)

    Schmiedek, Florian; Lövdén, Martin; Lindenberger, Ulman

    2013-09-01

    People often attribute poor performance to having bad days. Given that cognitive aging leads to lower average levels of performance and more moment-to-moment variability, one might expect that older adults should show greater day-to-day variability and be more likely to experience bad days than younger adults. However, both researchers and ordinary people typically sample only one performance per day for a given activity. Hence, the empirical basis for concluding that cognitive performance does substantially vary from day to day is inadequate. On the basis of data from 101 younger and 103 older adults who completed nine cognitive tasks in 100 daily sessions, we show that the contributions of systematic day-to-day variability to overall observed variability are reliable but small. Thus, the impression of good versus bad days is largely due to performance fluctuations at faster timescales. Despite having lower average levels of performance, older adults showed more consistent levels of performance across days.

  12. Jogging improved performance of a behavioral branching task: implications for prefrontal activation.

    Science.gov (United States)

    Harada, Taeko; Okagawa, Satoru; Kubota, Kisou

    2004-07-01

    We studied the effect of habitual jogging on the performance of a frontal lobe functioning test. Fourteen subjects were divided into a jogging trained group (TG) or a jogging untrained group (NG). The TG jogged for 12 weeks, for 30 min, 2.6 times per week, while the NG did not. We administered a prefrontal branching task (BR) combining a Spatial Delayed-Response Test (DR) and a Go/No-Go Test (GNG). Each test alone and a Simple Reaction Time Test (SR) were given as controls. All tests were given three times at 6 week intervals over 12 weeks in both groups. In the TG, the tests were given two times after termination of the jogging. The maximal oxygen uptake (VO2max) was measured in the TG during the 12 weeks. After 12 weeks, the correct performance rates in the BR task were more improved in the TG than in the NG. The control and reaction time tests were unchanged in both groups. The improved performance in the BR task in the TG decreased after stopping the jogging. The VO2max increased significantly during the 12 weeks of jogging in the TG. Thus, the habitual jogging improved performance in a prefrontal BR.

  13. Development of an Objective Space Suit Mobility Performance Metric Using Metabolic Cost and Functional Tasks

    Science.gov (United States)

    McFarland, Shane M.; Norcross, Jason

    2016-01-01

    Existing methods for evaluating EVA suit performance and mobility have historically concentrated on isolated joint range of motion and torque. However, these techniques do little to evaluate how well a suited crewmember can actually perform during an EVA. An alternative method of characterizing suited mobility through measurement of metabolic cost to the wearer has been evaluated at Johnson Space Center over the past several years. The most recent study involved six test subjects completing multiple trials of various functional tasks in each of three different space suits; the results indicated it was often possible to discern between different suit designs on the basis of metabolic cost alone. However, other variables may have an effect on real-world suited performance; namely, completion time of the task, the gravity field in which the task is completed, etc. While previous results have analyzed completion time, metabolic cost, and metabolic cost normalized to system mass individually, it is desirable to develop a single metric comprising these (and potentially other) performance metrics. This paper outlines the background upon which this single-score metric is determined to be feasible, and initial efforts to develop such a metric. Forward work includes variable coefficient determination and verification of the metric through repeated testing.

  14. Humans Integrate Monetary and Liquid Incentives to Motivate Cognitive Task Performance

    Directory of Open Access Journals (Sweden)

    Debbie Marianne Yee

    2016-01-01

    Full Text Available It is unequivocal that a wide variety of incentives can motivate behavior. However, few studies have explicitly examined whether and how different incentives are integrated in terms of their motivational influence. The current study examines the combined effects of monetary and liquid incentives on cognitive processing, and whether appetitive and aversive incentives have distinct influences. We introduce a novel task paradigm, in which participants perform cued task-switching for monetary rewards that vary parametrically across trials, with liquid incentives serving as post-trial performance feedback. Critically, the symbolic meaning of the liquid was held constant (indicating successful reward attainment, while liquid valence was blocked. In the first experiment, monetary rewards combined additively with appetitive liquid feedback to improve subject task performance. Aversive liquid feedback counteracted monetary reward effects in low monetary reward trials, particularly in a subset of participants who tended to avoid responding under these conditions. Self-report motivation ratings predicted behavioral performance above and beyond experimental effects. A follow-up experiment replicated the predictive power of motivation ratings even when only appetitive liquids were used, suggesting that ratings reflect idiosyncratic subjective values of, rather than categorical differences between, the liquid incentives. Together, the findings indicate an integrative relationship between primary and secondary incentives and potentially dissociable influences in modulating motivational value, while informing hypotheses regarding candidate neural mechanisms.

  15. Humans Integrate Monetary and Liquid Incentives to Motivate Cognitive Task Performance.

    Science.gov (United States)

    Yee, Debbie M; Krug, Marie K; Allen, Ariel Z; Braver, Todd S

    2015-01-01

    It is unequivocal that a wide variety of incentives can motivate behavior. However, few studies have explicitly examined whether and how different incentives are integrated in terms of their motivational influence. The current study examines the combined effects of monetary and liquid incentives on cognitive processing, and whether appetitive and aversive incentives have distinct influences. We introduce a novel task paradigm, in which participants perform cued task-switching for monetary rewards that vary parametrically across trials, with liquid incentives serving as post-trial performance feedback. Critically, the symbolic meaning of the liquid was held constant (indicating successful reward attainment), while liquid valence was blocked. In the first experiment, monetary rewards combined additively with appetitive liquid feedback to improve subject task performance. Aversive liquid feedback counteracted monetary reward effects in low monetary reward trials, particularly in a subset of participants who tended to avoid responding under these conditions. Self-report motivation ratings predicted behavioral performance above and beyond experimental effects. A follow-up experiment replicated the predictive power of motivation ratings even when only appetitive liquids were used, suggesting that ratings reflect idiosyncratic subjective values of, rather than categorical differences between, the liquid incentives. Together, the findings indicate an integrative relationship between primary and secondary incentives and potentially dissociable influences in modulating motivational value, while informing hypotheses regarding candidate neural mechanisms.

  16. The development of corpus callosum microstructure and associations with bimanual task performance in healthy adolescents.

    Science.gov (United States)

    Muetzel, Ryan L; Collins, Paul F; Mueller, Bryon A; M Schissel, Ann; Lim, Kelvin O; Luciana, Monica

    2008-02-15

    Cross-sectional and longitudinal volumetric studies suggest that the corpus callosum (CC) continues to mature structurally from infancy to adulthood. Diffusion tensor imaging (DTI) provides in vivo information about the directional organization of white matter microstructure and shows potential for elucidating even more subtle brain changes during adolescent development. We used DTI to examine CC microstructure in healthy right-handed adolescents (n=92, ages 9-24 years) and correlated the imaging data with motor task performance. The primary DTI variable was fractional anisotropy (FA), which reflects the degree of white matter's directional organization. Participants completed an alternating finger tapping test to assess interhemispheric transfer and motor speed. Task performance was significantly correlated with age. Analyses of variance indicated that 9- to 11-year-olds generally performed worse than each of the older groups. Males outperformed females. Significant positive correlations between age and FA were observed in the splenium of the CC, which interconnects posterior cortical regions. Analyses of variance indicated that individuals older than 18 years had significantly higher FA than 9- to 11-year-olds. FA levels in the genu and splenium correlated significantly with task performance. Regression analyses indicated that bimanual coordination was significantly predicted by age, gender, and splenium FA. Decreases in alternating finger tapping time and increases in FA likely reflect increased myelination in the CC and more efficient neuronal signal transmission. These findings expand upon existing neuroimaging reports of CC development by showing associations between bimanual coordination and white matter microstructural organization in an adolescent sample.

  17. Objective assessment of surgical performance and its impact on a national selection programme of candidates for higher surgical training in plastic surgery.

    LENUS (Irish Health Repository)

    Carroll, Sean M

    2012-02-01

    OBJECTIVE: The objective of this study was to develop and validate a transparent, fair and objective assessment programme for the selection of surgical trainees into higher surgical training (HST) in plastic surgery in the Republic of Ireland. METHODS: Thirty-four individuals applied for HST in plastic surgery at the Royal College of Surgeons in Ireland (RCSI) in the academic years 2005-2006 and 2006-2007. Eighteen were short-listed for interview and further assessment. All applicants were required to report on their undergraduate educational performance and their postgraduate professional development. Short-listed applicants completed validated objective assessment simulations of surgical skills, an interview and assessment of their suitability for a career in surgery. RESULTS: When applicants\\' short-listing scores were combined with their interview scores and assessment of their suitability for a career in surgery, individuals who were selected for HST in plastic surgery performed significantly better than those who were not (P<0.002). However, when the assessment of technical skills scores were added the significance level of this difference increased further (P<0.0001) as did the statistical power of the difference to 99.9%, thus increasing the robustness of the selection package. CONCLUSION: The results from this study suggest that the assessment protocol we used to select individuals for HST in plastic surgery reliably and statistically significantly discriminated between the performances of candidates.

  18. Self-reported Quality of ADL Task performance in Persons with Chronic Conditions

    DEFF Research Database (Denmark)

    Nielsen, Kristina Tomra; Wæhrens, Eva Ejlersen

    2016-01-01

    Background: Several studies have indicated that persons with chronic diseases perceive problems related to Activities of Daily Living (ADL), including Personal ADL (PADL) and Instrumental ADL (IADL). However, little is known about how persons with chronic diseases perceive the quality of their ADL...... groups with chronic diseases. Method: Persons with various chronic diseases including rheumatic diseases, cancer, chronic obstructive pulmonary disease and schizophrenia were included in the study. Data related to self-reported quality of ADL task performance were collected from 2007-2015 using the ADL...... in relation to selfreported quality of ADL task performance will be investigated both within and between diagnostic groups. Results and conclusion: Data extraction is in progress. We expect the results of the study to show both similarities and differences in relation to self-reported quality of both personal...

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

    Science.gov (United States)

    Washington, Gloria

    2012-01-01

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

  20. Voluntary exercise improves performance of a discrimination task through effects on the striatal dopamine system

    Science.gov (United States)

    Eddy, Meghan C.; Stansfield, Katherine J.; Green, John T.

    2014-01-01

    We have previously demonstrated that voluntary exercise facilitates discrimination learning in a modified T-maze. There is evidence implicating the dorsolateral striatum (DLS) as the substrate for this task. The present experiments examined whether changes in DLS dopamine receptors might underlie the exercise-associated facilitation. Infusing a D1R antagonist into the DLS prior to discrimination learning facilitated the performance of nonexercising rats but not exercising rats. Infusing a D2R antagonist impaired the performance of exercising rats but not nonexercising rats. Exercise-associated facilitation of this task may rely on an exercise-induced decrease in D1R and increase in D2R activation in the DLS. PMID:24934332

  1. Effects of gender, imagery ability, and sports practice on the performance of a mental rotation task.

    Science.gov (United States)

    Habacha, Hamdi; Molinaro, Corinne; Dosseville, Fabrice

    2014-01-01

    Mental rotation is one of the main spatial abilities necessary in the spatial transformation of mental images and the manipulation of spatial parameters. Researchers have shown that mental rotation abilities differ between populations depending on several variables. This study uses a mental rotation task to investigate effects of several factors on the spatial abilities of 277 volunteers. The results demonstrate that high and low imagers performed equally well on this tasks. Athletes outperformed nonathletes regardless of their discipline, and athletes with greater expertise outperformed those with less experience. The results replicate the previously reported finding that men exhibit better spatial abilities than women. However, with high amounts of practice, the women in the current study were able to perform as well as men.

  2. An exemplar model of performance in the artificial grammar task: holographic representation.

    Science.gov (United States)

    Jamieson, Randall K; Hauri, Brian R

    2012-06-01

    We apply a multitrace model of memory to explain performance in the artificial grammar task. The model blends the convolution method for representation from Jones and Mewhort's BEAGLE model (Jones, M. N., & Mewhort, D. J. K. (2007). Representing word meaning and order information in a composite holographic lexicon. Psychological Review, 114, 1-37) of semantic memory with the multitrace storage and retrieval model from Hintzman's MINERVA 2 model (Hintzman, D. L. (1986). "Schema abstraction" in a multiple-trace memory model. Psychological Review, 93, 411-428) of episodic memory. We report an artificial grammar experiment, and we fit the model to those data at the level of individual items. We argue that performance in the artificial grammar task is best understood as a process of retrospective inference from memory.

  3. Using mixed-initiative human-robot interaction to bound performance in a search task

    Energy Technology Data Exchange (ETDEWEB)

    Curtis W. Nielsen; Douglas A. Few; Devin S. Athey

    2008-12-01

    Mobile robots are increasingly used in dangerous domains, because they can keep humans out of harm’s way. Despite their advantages in hazardous environments, their general acceptance in other less dangerous domains has not been apparent and, even in dangerous environments, robots are often viewed as a “last-possible choice.” In order to increase the utility and acceptance of robots in hazardous domains researchers at the Idaho National Laboratory have both developed and tested novel mixed-initiative solutions that support the human-robot interactions. In a recent “dirty-bomb” experiment, participants exhibited different search strategies making it difficult to determine any performance benefits. This paper presents a method for categorizing the search patterns and shows that the mixed-initiative solution decreased the time to complete the task and decreased the performance spread between participants independent of prior training and of individual strategies used to accomplish the task.

  4. Architecture of a high-performance surgical guidance system based on C-arm cone-beam CT: software platform for technical integration and clinical translation

    Science.gov (United States)

    Uneri, Ali; Schafer, Sebastian; Mirota, Daniel; Nithiananthan, Sajendra; Otake, Yoshito; Reaungamornrat, Sureerat; Yoo, Jongheun; Stayman, J. Webster; Reh, Douglas; Gallia, Gary L.; Khanna, A. Jay; Hager, Gregory; Taylor, Russell H.; Kleinszig, Gerhard; Siewerdsen, Jeffrey H.

    2011-03-01

    Intraoperative imaging modalities are becoming more prevalent in recent years, and the need for integration of these modalities with surgical guidance is rising, creating new possibilities as well as challenges. In the context of such emerging technologies and new clinical applications, a software architecture for cone-beam CT (CBCT) guided surgery has been developed with emphasis on binding open-source surgical navigation libraries and integrating intraoperative CBCT with novel, application-specific registration and guidance technologies. The architecture design is focused on accelerating translation of task-specific technical development in a wide range of applications, including orthopaedic, head-and-neck, and thoracic surgeries. The surgical guidance system is interfaced with a prototype mobile C-arm for high-quality CBCT and through a modular software architecture, integration of different tools and devices consistent with surgical workflow in each of these applications is realized. Specific modules are developed according to the surgical task, such as: 3D-3D rigid or deformable registration of preoperative images, surgical planning data, and up-to-date CBCT images; 3D-2D registration of planning and image data in real-time fluoroscopy and/or digitally reconstructed radiographs (DRRs); compatibility with infrared, electromagnetic, and video-based trackers used individually or in hybrid arrangements; augmented overlay of image and planning data in endoscopic or in-room video; real-time "virtual fluoroscopy" computed from GPU-accelerated DRRs; and multi-modality image display. The platform aims to minimize offline data processing by exposing quantitative tools that analyze and communicate factors of geometric precision. The system was translated to preclinical phantom and cadaver studies for assessment of fiducial (FRE) and target registration error (TRE) showing sub-mm accuracy in targeting and video overlay within intraoperative CBCT. The work culminates in

  5. SURGICAL TREATMENT OF SEVERE (2-3 DEGREE DEFORMING ARTHROSIS OF FIRST METATARSOPHALANGEAL JOINT OF FOOT: TASKS, APPROACHES, TECHNIQUE

    Directory of Open Access Journals (Sweden)

    A. V. Mazalov

    2011-01-01

    Full Text Available Based on the experience of treating 67 patients (98 feet with deforming arthrosis of first metatarsophalangeal joint is shown that the treatment of this disease the distal decompressing osteotomy in combination with maximally radical the separation of the unions and cheilectomy possesses the significant health-improvement potential, which makes it possible to be turned to arthrodesis or arthroplasty only in the limiting cases of that the heavy cases of hallux rigidus. L-osteotomy 1-st metatarsus gives more than possibilities for the correction with the heavy deformations and the degenerate changes, the basic criterion of sufficiency of which is the volume of the intra-operating straightening of 1-st fingers reached. Optimum is reaching the straightening 1-st toes to 65° even above. An indispensable stage of complex operation is maximally radical of cheilectomy. During the formation of arthrodesis 1-st metatarsophalangeal joint in the horizontal plane the axis of 1 finger should be oriented in parallel to axis second metatarsal bones. The sagittal angle of the formation of arthrodesis depends on the manifestation of valgus of rear division. Active postoperative conducting essentially improves the distant results of the surgical treatment of deforming arthrosis of first metatarsophalangeal joint.

  6. Goal striving strategies and effort mobilization: When implementation intentions reduce effort-related cardiac activity during task performance.

    Science.gov (United States)

    Freydefont, Laure; Gollwitzer, Peter M; Oettingen, Gabriele

    2016-09-01

    Two experiments investigate the influence of goal and implementation intentions on effort mobilization during task performance. Although numerous studies have demonstrated the beneficial effects of setting goals and making plans on performance, the effects of goals and plans on effort-related cardiac activity and especially the cardiac preejection period (PEP) during goal striving have not yet been addressed. According to the Motivational Intensity Theory, participants should increase effort mobilization proportionally to task difficulty as long as success is possible and justified. Forming goals and making plans should allow for reduced effort mobilization when participants perform an easy task. However, when the task is difficult, goals and plans should differ in their effect on effort mobilization. Participants who set goals should disengage, whereas participants who made if-then plans should stay in the field showing high effort mobilization during task performance. As expected, using an easy task in Experiment 1, we observed a lower cardiac PEP in both the implementation intention and the goal intention condition than in the control condition. In Experiment 2, we varied task difficulty and demonstrated that while participants with a mere goal intention disengaged from difficult tasks, participants with an implementation intention increased effort mobilization proportionally with task difficulty. These findings demonstrate the influence of goal striving strategies (i.e., mere goals vs. if-then plans) on effort mobilization during task performance.

  7. Impact of Task Performance Fraud Risk Assessment on Forensic Skills and Mindsets: Experience from Nigeria

    OpenAIRE

    Popoola, Oluwatoyin Muse Johnson; Che-Ahmad, Ayoib; Samsudin, Rose Shamsiah

    2014-01-01

    This paper discusses the impact of task performance, fraud risk assessment and forensic accountants and auditors’ skills and mindsets in the Nigerian public sector. It also draws the attention of the users of public sector accountants and auditors such as the Economic and Financial Crimes Commission, the Independent Corrupt Practices Commission, Special Control Unit of Money Laundering, Terrorism Financing and White collar crimes. The objective of the study is to enhance the fraud risk ...

  8. The Impact of Task Performance Fraud Risk Assessment on Forensic Skills and Mindsets: A Conceptual Model

    OpenAIRE

    Popoola, Oluwatoyin Muse Johnson; Che-Ahmad, Ayoib; Samsudin, Rose Shamsiah; Yussof, Rushami Zien

    2013-01-01

    This paper discusses the impact of task performance, fraud risk assessment and forensic accountants and auditors’ skills and mindsets in the Nigerian public sector. It also draws the attention of the users of public sector accountants and auditors such as the Economic and Financial Crimes Commission, the Independent and Corrupt Practices Commission,Special Control Unit of Money Laundering, Terrorism Financing and white collar crimes. The objective of the study is to enhance the fraud risk ass...

  9. Performance of Children with Autism Spectrum Disorders on the Dimension-Change Card Sort Task

    OpenAIRE

    Dichter, Gabriel S.; Radonovich, Krestin J.; Turner-Brown, Lauren M.; LAM, KRISTEN S. L.; HOLTZCLAW, TIA N.; Bodfish, James W.

    2010-01-01

    Restricted and repetitive behaviors in autism spectrum disorders have been conceptualized to reflect impaired executive functions. In the present study, we investigated the performance of 6–17-year-old children with and without an autism spectrum disorder on a dimension-change card sort task that explicitly indicated sorting rules on every trial. Diagnostic groups did not differ in speed of responses after the first rule switch or in speed or accuracy on blocks with mixed versus single sort r...

  10. The potential impact of 3D telepresence technology on task performance in emergency trauma care

    DEFF Research Database (Denmark)

    Söderholm, Hanna M.; Sonnenwald, Diane H.; Cairns, Bruce

    2007-01-01

    Emergency trauma is a major health problem worldwide. To evaluate the potential of emerging 3D telepresence technology for facilitating paramedic - physician collaboration while providing emergency medical trauma care we conducted a between-subjects post-test experimental lab study. During...... proxy condition also reported higher levels of self-efficacy. These results indicate 3D telepresence technology has potential to improve paramedics' performance of complex emergency medical tasks and improve emergency trauma health care when designed appropriately. © 2007 ACM....

  11. Improvements of task performance in daily life after acquired brain injury using commonly available everyday technology.

    OpenAIRE

    Lindén, Anita; Lexell, Jan; Larsson Lund, Maria

    2011-01-01

    Purpose. To investigate how individualised occupation-based interventions with commonly available everyday technology (ET) can compensate for perceived difficulties with daily life tasks after an aquired brain injury (ABI) and improve satisfaction with occupational performance. Method. This intervention study was designed as a multiple case study according to Yin. Ten men and women with an ABI (traumatic or non-traumatic) participated. Data were collected through interviews, observations and ...

  12. The effects of color scheme on the appraisal of an office environment and task performance

    OpenAIRE

    Öztürk, Elif

    2010-01-01

    Ankara : The Department of Interior Architecture and Environmental Design and the Institute of Economics and Social Sciences of Bilkent University, 2010. Thesis (Master's) -- Bilkent University, 2010. Includes bibliographical references leaves 86-90. The purpose of this study is to explore the differences between achromatic and chromatic schemes in the appraisal of an office environment and task performance. To investigate only the hue effect on the subjective impressions of ...

  13. Is performance on probed serial recall tasks in schizophrenia related to duration of Attentional Blink?

    Directory of Open Access Journals (Sweden)

    David P. McAllindon

    2017-03-01

    Full Text Available Schizophrenia is associated with a deficit in working memory, with the degree of working memory impairment related to the level of social and occupational functioning. This study tests the hypothesis that the working memory deficits in individuals with schizophrenia can be explained by slow processing of visual stimuli, as measured by the attentional blink (AB task. Individuals with schizophrenia (SC and controls (HC were recruited from an early intervention service for psychosis and the local community. Data from 16 SC (11M/5F, mean = 26.4 yo and 20 age-matched HC (11M/9F, mean = 25.8 yo were analyzed. Each subject performed an AB task to determine their AB duration, defined as the lag to reach their plateau performance (ltpp. As expected, mean AB duration in the SC group (575 ms was significantly slower than HC (460 ms; p = 0.007. Recall accuracy of the SC group on a working memory task, a 6-item probed serial recall task (PSR, was reduced compared to the HC group at a standard interstimulus interval (ISI (p = 0.002. When the individual's AB duration was then used to adjust the ISI on the PSR task to three relative ISI rates (Slow (2 × ltpp, Medium (ltpp and Fast (1/2 × ltpp, performance on the PSR task was affected by group, position and ISI and qualified by an ISI ∗ position (p = 0.001 and a trend to a triple interaction (p = 0.054. There was main effect of group at all ISIs, but group ∗ position interaction only at Slow ISI (p = 0.01. Our interpretation of the results is that absolute ISI, rather than ISI relative to AB duration, affected performance.

  14. Effects of state anxiety on performance using a task-switching paradigm: an investigation of attentional control theory.

    Science.gov (United States)

    Derakshan, Nazanin; Smyth, Sinéad; Eysenck, Michael W

    2009-12-01

    Low- and high-anxious participants performed arithmetical tasks under task-switching or nontask-switching conditions. These tasks were low or high in complexity. The task on each trial was either explicitly cued or not cued. We assumed that demands on attentional control would be greater in the task-switching condition than in the nontask-switching condition, and would be greater with high-complexity tasks than with low-complexity ones. We also assumed that demands on attentional control would be greater when cues were absent rather than present. According to attentional control theory (Eysenck, Derakshan, Santos, & Calvo, 2007), anxiety impairs attentional control processes required to shift attention optimally within and between tasks. We predicted that there would be greater negative effects of high state anxiety in the task-switching condition than in the nontask-switching condition. Our theoretical predictions were supported, suggesting that state anxiety reduces attentional control.

  15. Integrating a novel shape memory polymer into surgical meshes to improve device performance during laparoscopic hernia surgery

    Science.gov (United States)

    Zimkowski, Michael M.

    About 600,000 hernia repair surgeries are performed each year. The use of laparoscopic minimally invasive techniques has become increasingly popular in these operations. Use of surgical mesh in hernia repair has shown lower recurrence rates compared to other repair methods. However in many procedures, placement of surgical mesh can be challenging and even complicate the procedure, potentially leading to lengthy operating times. Various techniques have been attempted to improve mesh placement, including use of specialized systems to orient the mesh into a specific shape, with limited success and acceptance. In this work, a programmed novel Shape Memory Polymer (SMP) was integrated into commercially available polyester surgical meshes to add automatic unrolling and tissue conforming functionalities, while preserving the intrinsic structural properties of the original surgical mesh. Tensile testing and Dynamic Mechanical Analysis was performed on four different SMP formulas to identify appropriate mechanical properties for surgical mesh integration. In vitro testing involved monitoring the time required for a modified surgical mesh to deploy in a 37°C water bath. An acute porcine model was used to test the in vivo unrolling of SMP integrated surgical meshes. The SMP-integrated surgical meshes produced an automated, temperature activated, controlled deployment of surgical mesh on the order of several seconds, via laparoscopy in the animal model. A 30 day chronic rat model was used to test initial in vivo subcutaneous biocompatibility. To produce large more clinical relevant sizes of mesh, a mold was developed to facilitate manufacturing of SMP-integrated surgical mesh. The mold is capable of manufacturing mesh up to 361 cm2, which is believed to accommodate the majority of clinical cases. Results indicate surgical mesh modified with SMP is capable of laparoscopic deployment in vivo, activated by body temperature, and possesses the necessary strength and

  16. Pupil responses to task requirement in goal-directed movements

    OpenAIRE

    Jiang, Xianta

    2014-01-01

    Objectively measuring the operators’ task workload in goal-directed motor tasks such as surgical operations, is important for performance and safety. This thesis presents an approach for objectively measuring task workload in goal-directed movements using an important eye response: the pupil diameter. We demonstrate how to capture movement-related pupil size changes during motor tasks, investigate how the pupil responds to task requirement, and show that the pupil diameter can be employed a...

  17. Task-sharing or public finance for the expansion of surgical access in rural Ethiopia: an extended cost-effectiveness analysis.

    Science.gov (United States)

    Shrime, Mark G; Verguet, Stéphane; Johansson, Kjell Arne; Desalegn, Dawit; Jamison, Dean T; Kruk, Margaret E

    2016-07-01

    Despite a high burden of surgical disease, access to surgical services in low- and middle-income countries is often limited. In line with the World Health Organization's current focus on universal health coverage and equitable access to care, we examined how policies to expand access to surgery in rural Ethiopia would impact health, impoverishment and equity. An extended cost-effectiveness analysis was performed. Deterministic and stochastic models of surgery in rural Ethiopia were constructed, utilizing pooled estimates of costs and probabilities from national surveys and published literature. Model calibration and validation were performed against published estimates, with sensitivity analyses on model assumptions to check for robustness. Outcomes of interest were the number of deaths averted, the number of cases of poverty averted and the number of cases of catastrophic expenditure averted for each policy, divided across wealth quintiles. Health benefits, financial risk protection and equity appear to be in tension in the expansion of access to surgical care in rural Ethiopia. Health benefits from each of the examined policies accrued primarily to the poor. However, without travel vouchers, many policies also induced impoverishment in the poor while providing financial risk protection to the rich, calling into question the equitable distribution of benefits by these policies. Adding travel vouchers removed the impoverishing effects of a policy but decreased the health benefit that could be bought per dollar spent. These results were robust to sensitivity analyses.

  18. Effect of nicotine on brain activation during performance of a working memory task.

    Science.gov (United States)

    Ernst, M; Matochik, J A; Heishman, S J; Van Horn, J D; Jons, P H; Henningfield, J E; London, E D

    2001-04-10

    Nicotine influences cognition and behavior, but the mechanisms by which these effects occur are unclear. By using positron emission tomography, we measured cognitive activation (increases in relative regional cerebral blood flow) during a working memory task [2-back task (2BT)] in 11 abstinent smokers and 11 ex-smokers. Assays were performed both after administration of placebo gum and 4-mg nicotine gum. Performance on the 2BT did not differ between groups in either condition, and the pattern of brain activation by the 2BT was consistent with reports in the literature. However, in the placebo condition, activation in ex-smokers predominated in the left hemisphere, whereas in smokers, it occurred in the right hemisphere. When nicotine was administered, activation was reduced in smokers but enhanced in ex-smokers. The lateralization of activation as a function of nicotine dependence suggests that chronic exposure to nicotine or withdrawal from nicotine affects cognitive strategies used to perform the memory task. Furthermore, the lack of enhancement of activation after nicotine administration in smokers likely reflects tolerance.

  19. Investigating the Effects of Concurrent Performance of Physical and Cognitive Demanding Task in Paced Assembly Lines

    Directory of Open Access Journals (Sweden)

    Shakil Ahmed Shaikh

    2013-07-01

    Full Text Available The study was undertaken to investigate the effects of pacing on aspects of performance at an assembly task and on the operators' responses related to work behaviour, perceived workload and perceived stress. A particular objective of the study was to investigate whether physical and cognitive demands may interact in their influences on these effects. An assembly task was simulated in the laboratory and the level of pacing imposed, work height and memory load within the task were all varied. The results showed that the type of pacing commonly imposed (as is common with a lean manufacturing Takt time system in industry can significantly affect both performance and perceived workload and stress. Physical demands (through work height affecting posture and mental demand (through memory load were also found to have significant effects, as would be expected from the many studies of these in the literature. More importantly, some interactions were found between pacing and work height in their effects on quality of assembly and the operator's own rating of performance, and between work height and memory load in their effects on errors. These findings will need to be taken into account by companies when implementing Takt time systems.

  20. Through gendered lens:explaining Chinese caregivers' task performance and care reward.

    Science.gov (United States)

    Zhan, Heying Jenny

    2004-01-01

    The Chinese cultural norm of xiao, or filial piety, has long been held responsible for the practice of familial caregiving for older parents. Yet few explore the gendered nature of such a cultural practice in the current changing economic dynamics. Using data collected in 1997-1999 from 110 Chinese caregivers who were caring for physically dependent elder parents, this researcher explores the influence of changing economic conditions and Chinese cultural values in caregiver task performance and reward. Findings suggest that Chinese caregiving is highly gendered: Women are more likely to be unemployed and provide more personal care than men; sons are not more likely than daughters to provide financial assistance for parents. Chinese cultural values are playing an important role sanctioning caregiver task performance. Caregivers who believed in patrilocal norms provided more financial assistance; caregivers who reported higher social pressure provided more personal care. While the caregivers' report of social pressure is positively related to the caregivers' performance in personal care tasks, it is negatively related to caregiver reward. The author further explores the gendered implications for the changing economy and culture in China.