Flexible Modeling of Latent Task Structures in Multitask Learning

DTIC Science & Technology

2012-06-26

Flexible Modeling of Latent Task Structures in Multitask Learning Alexandre Passos† apassos@cs.umass.edu Computer Science Department, University of...of Maryland, College Park, MD USA Abstract Multitask learning algorithms are typically designed assuming some fixed, a priori known latent structure...shared by all the tasks. However, it is usually unclear what type of latent task structure is the most ap- propriate for a given multitask learning prob

Scaffolding Interaction in Parent-Child Dyads: Multimodal Analysis of Parental Scaffolding with Task and Non-Task Oriented Children

ERIC Educational Resources Information Center

Salonen, Pekka; Lepola, Janne; Vauras, Marja

2007-01-01

In this exploratory study we conceptualized and explored socio-cognitive, emotional and motivational regulatory processes displayed in scaffolding interaction between parents and their non-task and task-oriented children. Based on the dynamic systems view and findings from developmental research, we assumed that parents with non-task oriented and…

Brief Report: Impaired Flexible Item Selection Task (FIST) in School-Age Children with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Yerys, Benjamin E.; Wolff, Brian C.; Moody, Eric; Pennington, Bruce F.; Hepburn, Susan L.

2012-01-01

Cognitive flexibility has been measured with inductive reasoning or explicit rule tasks in individuals with autism spectrum disorders (ASD). The "Flexible Item Selection Task" (FIST) differs from previous cognitive flexibility tasks in ASD research by giving children an abstract, ambiguous rule to switch. The ASD group (N = 22; Mean age = 8.28…

Thin film with oriented cracks on a flexible substrate

DOEpatents

Feng, Bao; McGilvray, Andrew; Shi, Bo

2010-07-27

A thermoelectric film is disclosed. The thermoelectric film includes a substrate that is substantially electrically non-conductive and flexible and a thermoelectric material that is deposited on at least one surface of the substrate. The thermoelectric film also includes multiple cracks oriented in a predetermined direction.

ERP evidence for flexible adjustment of retrieval orientation and its influence on familiarity.

PubMed

Ecker, Ullrich K H; Zimmer, Hubert D

2009-10-01

The assumption was tested that familiarity memory as indexed by a mid-frontal ERP old-new effect is modulated by retrieval orientation. A randomly cued category-based versus exemplar-specific recognition memory test, requiring flexible adjustment of retrieval orientation, was conducted. Results show that the mid-frontal ERP old-new effect is sensitive to the manipulation of study-test congruency-that is, whether the same object is repeated identically or a different category exemplar is presented at test. Importantly, the effect pattern depends on subjects' retrieval orientation. With a specific orientation, only same items elicited an early old-new effect (same > different = new), whereas in the general condition, the old-new effect was graded (same > different > new). This supports the view that both perceptual and conceptual processes can contribute to familiarity memory and demonstrates that the rather automatic process of familiarity is not only data driven but influenced by top-down retrieval orientation, which subjects are able to adjust on a flexible basis.

The Relationships among Students' Future-Oriented Goals and Subgoals, Perceived Task Instrumentality, and Task-Oriented Self-Regulation Strategies in an Academic Environment

ERIC Educational Resources Information Center

Tabachnick, Sharon E.; Miller, Raymond B.; Relyea, George E.

2008-01-01

The authors performed path analysis, followed by a bootstrap procedure, to test the predictions of a model explaining the relationships among students' distal future goals (both extrinsic and intrinsic), their adoption of a middle-range subgoal, their perceptions of task instrumentality, and their proximal task-oriented self-regulation strategies.…

Flexible medical image management using service-oriented architecture.

PubMed

Shaham, Oded; Melament, Alex; Barak-Corren, Yuval; Kostirev, Igor; Shmueli, Noam; Peres, Yardena

2012-01-01

Management of medical images increasingly involves the need for integration with a variety of information systems. To address this need, we developed Content Management Offering (CMO), a platform for medical image management supporting interoperability through compliance with standards. CMO is based on the principles of service-oriented architecture, implemented with emphasis on three areas: clarity of business process definition, consolidation of service configuration management, and system scalability. Owing to the flexibility of this platform, a small team is able to accommodate requirements of customers varying in scale and in business needs. We describe two deployments of CMO, highlighting the platform's value to customers. CMO represents a flexible approach to medical image management, which can be applied to a variety of information technology challenges in healthcare and life sciences organizations.

The Multidimensional Card Selection Task: A new way to measure concurrent cognitive flexibility in preschoolers.

PubMed

Podjarny, Gal; Kamawar, Deepthi; Andrews, Katherine

2017-07-01

Most executive function research examining preschoolers' cognitive flexibility, the ability to think about something in more than one way, has focused on preschoolers' facility for sequentially switching their attention from one dimension to another (e.g., sorting bivalent cards first by color and then by shape). We know very little about preschoolers' ability to coordinate more than one dimension simultaneously (concurrent cognitive flexibility). Here we report on a new task, the Multidimensional Card Selection Task, which was designed to measure children's ability to consider two dimensions, and then three dimensions, concurrently (e.g., shape and size, and then shape, size, and color). More than half of the preschoolers in our sample of 107 (50 3-year-olds and 57 4-year-olds) could coordinate three dimensions simultaneously and consistently across three test trials. Furthermore, performance on the Multidimensional Card Selection Task was related, but not identical, to performance on other cognitive tasks, including a widely used measure of switching cognitive flexibility (the Dimensional Change Card Sort). The Multidimensional Card Selection Task provides a new way to measure concurrent cognitive flexibility in preschoolers, and opens another avenue for exploring the emergence of early cognitive flexibility development. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of reading-oriented tasks on students' reading comprehension of geometry proof

NASA Astrophysics Data System (ADS)

Yang, Kai-Lin; Lin, Fou-Lai

2012-06-01

This study compared the effects of reading-oriented tasks and writing-oriented tasks on students' reading comprehension of geometry proof (RCGP). The reading-oriented tasks were designed with reading strategies and the idea of problem posing. The writing-oriented tasks were consistent with usual proof instruction for writing a proof and applying it. Twenty-two classes of ninth-grade students ( N = 683), aged 14 to 15 years, and 12 mathematics teachers participated in this quasi-experimental classroom study. While the experimental group was instructed to read and discuss the reading tasks in two 45-minute lessons, the control group was instructed to prove and apply the same propositions. Generalised estimating equation (GEE) method was used to compare the scores of the post-test and the delayed post-test with the pre-test scores as covariates. Results showed that the total scores of the delayed post-test of the experimental group were significantly higher than those of the control group. Furthermore, the scores of the experimental group on all facets of reading comprehension except the application facet were significantly higher than those of the control group for both the post-test and delayed post-test.

Motivational orientations and task autonomy fit: effects on organizational attraction.

PubMed

Wu, Yu-Chi

2012-02-01

The main purpose of this study was to investigate whether there is congruence between applicant needs (i.e., motivational orientations) and what is available (i.e., task autonomy) from an organizational perspective based on the fit between needs and supply. The fit between work motivation and task autonomy was examined to see whether it was associated with organizational attraction. This experimental study included two phases. Phase 1 participants consisted of 446 undergraduate students, of whom 228 were recruited to participate in Phase 2. The fit relations between task autonomy and intrinsic motivation and between task control and extrinsic motivation were characterized. Findings indicated that the fit between work motivation and task autonomy was positively associated with organizational attraction. Based on these results, it may be inferred that employers should emphasize job characteristics such as autonomy or control orientations to attract individuals, and focus on the most suitable work motivations for their organizations.

Task-Oriented Spoken Dialog System for Second-Language Learning

ERIC Educational Resources Information Center

Kwon, Oh-Woog; Kim, Young-Kil; Lee, Yunkeun

2016-01-01

This paper introduces a Dialog-Based Computer Assisted second-Language Learning (DB-CALL) system using task-oriented dialogue processing technology. The system promotes dialogue with a second-language learner for a specific task, such as purchasing tour tickets, ordering food, passing through immigration, etc. The dialog system plays a role of a…

Dual-task results and the lateralization of spatial orientation: artifact of test selection?

PubMed

Bowers, C A; Milham, L M; Price, C

1998-01-01

An investigation was conducted to identify the degree to which results regarding the lateralization of spatial orientation among men and women are artifacts of test selection. A dual-task design was used to study possible lateralization differences, providing baseline and dual-task measures of spatial-orientation performance, right- and left-hand tapping, and vocalization of "cat, dog, horse." The Guilford-Zimmerman Test (Guilford & Zimmerman, 1953), the Eliot-Price Test (Eliot & Price, 1976), and the Stumpf-Fay Cube Perspectives Test (Stumpf & Fay, 1983) were the three spatial-orientation tests used to investigate possible artifacts of test selection. Twenty-eight right-handed male and 39 right-handed female undergraduates completed random baseline and dual-task sessions. Analyses indicated no significant sex-related differences in spatial-orientation ability for all three tests. Furthermore, there was no evidence of differential lateralization of spatial orientation between the sexes.

High-Frequency Binaural Beats Increase Cognitive Flexibility: Evidence from Dual-Task Crosstalk.

PubMed

Hommel, Bernhard; Sellaro, Roberta; Fischer, Rico; Borg, Saskia; Colzato, Lorenza S

2016-01-01

Increasing evidence suggests that cognitive-control processes can be configured to optimize either persistence of information processing (by amplifying competition between decision-making alternatives and top-down biasing of this competition) or flexibility (by dampening competition and biasing). We investigated whether high-frequency binaural beats, an auditory illusion suspected to act as a cognitive enhancer, have an impact on cognitive-control configuration. We hypothesized that binaural beats in the gamma range bias the cognitive-control style toward flexibility, which in turn should increase the crosstalk between tasks in a dual-task paradigm. We replicated earlier findings that the reaction time in the first-performed task is sensitive to the compatibility between the responses in the first and the second task-an indication of crosstalk. As predicted, exposing participants to binaural beats in the gamma range increased this effect as compared to a control condition in which participants were exposed to a continuous tone of 340 Hz. These findings provide converging evidence that the cognitive-control style can be systematically biased by inducing particular internal states; that high-frequency binaural beats bias the control style toward more flexibility; and that different styles are implemented by changing the strength of local competition and top-down bias.

Task oriented training improves the balance outcome & reducing fall risk in diabetic population.

PubMed

Ghazal, Javeria; Malik, Arshad Nawaz; Amjad, Imran

2016-01-01

The objective was to determine the balance impairments and to compare task oriented versus traditional balance training in fall reduction among diabetic patients. The randomized control trial with descriptive survey and 196 diabetic patients were recruited to assess balance impairments through purposive sampling technique. Eighteen patients were randomly allocated into two groups; task oriented balance training group TOB (n=8) and traditional balance training group TBT (n=10). The inclusion criteria were 30-50 years age bracket and diagnosed cases of Diabetes Mellitus with neuropathy. The demographics were taken through standardized & valid assessment tools include Berg Balance Scale and Functional Reach Test. The measurements were obtained at baseline, after 04 and 08 weeks of training. The mean age of the participants was 49 ±6.79. The result shows that 165(84%) were at moderate risk of fall and 31(15%) were at mild risk of fall among total 196 diabetic patients. There was significant improvement (p <0.05) in task oriented balance training group for dynamic balance, anticipatory balance and reactive balance after 8 weeks of training as compare to traditional balance training. Task oriented balance training is effective in improving the dynamic, anticipator and reactive balance. The task oriented training reduces the risk of falling through enhancing balance outcome.

Cognitive Flexibility in ASD; Task Switching with Emotional Faces

ERIC Educational Resources Information Center

de Vries, Marieke; Geurts, Hilde M.

2012-01-01

Children with autism spectrum disorders (ASDs) show daily cognitive flexibility deficits, but laboratory data are unconvincing. The current study aimed to bridge this gap. Thirty-one children with ASD (8-12 years) and 31 age- and IQ-matched typically developing children performed a gender emotion switch task. Unannounced switches and complex…

Self-Presentation in Task-Oriented Leadership Situations.

ERIC Educational Resources Information Center

Leary, Mark R.; Schlenker, Barry R.

To examine tactical self-presentations (images persons display publicly) in task-oriented leadership situations, 128 subjects (56 male and 72 female) were assigned leadership positions in groups that did very well or very poorly. The leaders learned that either they or the group-at-large were responsible for the performance and that the other…

Differentiation of rodent behavioral phenotypes and methylphenidate action in sustained and flexible attention tasks.

PubMed

Chu, Richard; Shumsky, Jed; Waterhouse, Barry D

2016-06-15

Methyphenidate (MPH) is the primary drug treatment of choice for ADHD. It is also frequently used off-label as a cognitive enhancer by otherwise healthy individuals from all age groups and walks of life. Military personnel, students, and health professionals use MPH illicitly to increase attention and improve workplace performance over extended periods of work activity. Despite the frequency of its use, the efficacy of MPH to enhance cognitive function across individuals and in a variety of circumstances is not well characterized. We sought to better understand MPH׳s cognitive enhancing properties in two different rodent models of attention. We found that MPH could enhance performance in a sustained attention task, but that its effects in this test were subject dependent. More specifically, MPH increased attention in low baseline performing rats but had little to no effect on high performing rats. MPH exerted a similar subject specific effect in a test of flexible attention, i.e. the attention set shifting task. In this test MPH increased behavioral flexibility in animals with poor flexibility but impaired performance in more flexible animals. Overall, our results indicate that the effects of MPH are subject-specific and depend on the baseline level of performance. Furthermore, good performance in in the sustained attention task was correlated with good performance in the flexible attention task; i.e. animals with better vigilance exhibited greater behavioral flexibility. The findings are discussed in terms of potential neurobiological substrates, in particular noradrenergic mechanisms, that might underlie subject specific performance and subject specific responses to MPH. This article is part of a Special Issue entitled SI: Noradrenergic System. Copyright © 2016 Elsevier B.V. All rights reserved.

Task oriented training improves the balance outcome & reducing fall risk in diabetic population

PubMed Central

Ghazal, Javeria; Malik, Arshad Nawaz; Amjad, Imran

2016-01-01

Objectives: The objective was to determine the balance impairments and to compare task oriented versus traditional balance training in fall reduction among diabetic patients. Methods: The randomized control trial with descriptive survey and 196 diabetic patients were recruited to assess balance impairments through purposive sampling technique. Eighteen patients were randomly allocated into two groups; task oriented balance training group TOB (n=8) and traditional balance training group TBT (n=10). The inclusion criteria were 30-50 years age bracket and diagnosed cases of Diabetes Mellitus with neuropathy. The demographics were taken through standardized & valid assessment tools include Berg Balance Scale and Functional Reach Test. The measurements were obtained at baseline, after 04 and 08 weeks of training. Results: The mean age of the participants was 49 ±6.79. The result shows that 165(84%) were at moderate risk of fall and 31(15%) were at mild risk of fall among total 196 diabetic patients. There was significant improvement (p <0.05) in task oriented balance training group for dynamic balance, anticipatory balance and reactive balance after 8 weeks of training as compare to traditional balance training. Conclusion: Task oriented balance training is effective in improving the dynamic, anticipator and reactive balance. The task oriented training reduces the risk of falling through enhancing balance outcome. PMID:27648053

The Influence of Achievement Goal Orientations and Task Concreteness on Situational Interest

ERIC Educational Resources Information Center

Tapola, Anna; Jaakkola, Tomi; Niemivirta, Markku

2014-01-01

This study investigated changes in elementary school students' (n = 140) situational interest as a function of achievement goal orientation profiles and task characteristics. The authors repeatedly measured situational interest during a simulated science learning task in 2 task conditions that differed in the concreteness of the task elements. The…

High-Frequency Binaural Beats Increase Cognitive Flexibility: Evidence from Dual-Task Crosstalk

PubMed Central

Hommel, Bernhard; Sellaro, Roberta; Fischer, Rico; Borg, Saskia; Colzato, Lorenza S.

2016-01-01

Increasing evidence suggests that cognitive-control processes can be configured to optimize either persistence of information processing (by amplifying competition between decision-making alternatives and top-down biasing of this competition) or flexibility (by dampening competition and biasing). We investigated whether high-frequency binaural beats, an auditory illusion suspected to act as a cognitive enhancer, have an impact on cognitive-control configuration. We hypothesized that binaural beats in the gamma range bias the cognitive-control style toward flexibility, which in turn should increase the crosstalk between tasks in a dual-task paradigm. We replicated earlier findings that the reaction time in the first-performed task is sensitive to the compatibility between the responses in the first and the second task—an indication of crosstalk. As predicted, exposing participants to binaural beats in the gamma range increased this effect as compared to a control condition in which participants were exposed to a continuous tone of 340 Hz. These findings provide converging evidence that the cognitive-control style can be systematically biased by inducing particular internal states; that high-frequency binaural beats bias the control style toward more flexibility; and that different styles are implemented by changing the strength of local competition and top-down bias. PMID:27605922

The Role of Learning Tasks on Attitude Change Using Cognitive Flexibility Hypertext Systems

ERIC Educational Resources Information Center

Godshalk, Veronica M.; Harvey, Douglas M.; Moller, Leslie

2004-01-01

In this study, the authors examined the impact of task assignment on the effectiveness of a Web-based experiential exercise based on cognitive flexibility theory to enlighten learner attitudes toward the ill-structured topic of sexual harassment. In the research study, we sought to shed light on the use of a cognitive flexibility approach when…

Effects of virtual reality-based training and task-oriented training on balance performance in stroke patients.

PubMed

Lee, Hyung Young; Kim, You Lim; Lee, Suk Min

2015-06-01

[Purpose] This study aimed to investigate the clinical effects of virtual reality-based training and task-oriented training on balance performance in stroke patients. [Subjects and Methods] The subjects were randomly allocated to 2 groups: virtual reality-based training group (n = 12) and task-oriented training group (n = 12). The patients in the virtual reality-based training group used the Nintendo Wii Fit Plus, which provided visual and auditory feedback as well as the movements that enabled shifting of weight to the right and left sides, for 30 min/day, 3 times/week for 6 weeks. The patients in the task-oriented training group practiced additional task-oriented programs for 30 min/day, 3 times/week for 6 weeks. Patients in both groups also underwent conventional physical therapy for 60 min/day, 5 times/week for 6 weeks. [Results] Balance and functional reach test outcomes were examined in both groups. The results showed that the static balance and functional reach test outcomes were significantly higher in the virtual reality-based training group than in the task-oriented training group. [Conclusion] This study suggested that virtual reality-based training might be a more feasible and suitable therapeutic intervention for dynamic balance in stroke patients compared to task-oriented training.

Effects of virtual reality-based training and task-oriented training on balance performance in stroke patients

PubMed Central

Lee, Hyung Young; Kim, You Lim; Lee, Suk Min

2015-01-01

[Purpose] This study aimed to investigate the clinical effects of virtual reality-based training and task-oriented training on balance performance in stroke patients. [Subjects and Methods] The subjects were randomly allocated to 2 groups: virtual reality-based training group (n = 12) and task-oriented training group (n = 12). The patients in the virtual reality-based training group used the Nintendo Wii Fit Plus, which provided visual and auditory feedback as well as the movements that enabled shifting of weight to the right and left sides, for 30 min/day, 3 times/week for 6 weeks. The patients in the task-oriented training group practiced additional task-oriented programs for 30 min/day, 3 times/week for 6 weeks. Patients in both groups also underwent conventional physical therapy for 60 min/day, 5 times/week for 6 weeks. [Results] Balance and functional reach test outcomes were examined in both groups. The results showed that the static balance and functional reach test outcomes were significantly higher in the virtual reality-based training group than in the task-oriented training group. [Conclusion] This study suggested that virtual reality-based training might be a more feasible and suitable therapeutic intervention for dynamic balance in stroke patients compared to task-oriented training. PMID:26180341

Determination of helix orientations in a flexible DNA by multi-frequency EPR spectroscopy.

PubMed

Grytz, C M; Kazemi, S; Marko, A; Cekan, P; Güntert, P; Sigurdsson, S Th; Prisner, T F

2017-11-15

Distance measurements are performed between a pair of spin labels attached to nucleic acids using Pulsed Electron-Electron Double Resonance (PELDOR, also called DEER) spectroscopy which is a complementary tool to other structure determination methods in structural biology. The rigid spin label Ç, when incorporated pairwise into two helical parts of a nucleic acid molecule, allows the determination of both the mutual orientation and the distance between those labels, since Ç moves rigidly with the helix to which it is attached. We have developed a two-step protocol to investigate the conformational flexibility of flexible nucleic acid molecules by multi-frequency PELDOR. In the first step, a library with a broad collection of conformers, which are in agreement with topological constraints, NMR restraints and distances derived from PELDOR, was created. In the second step, a weighted structural ensemble of these conformers was chosen, such that it fits the multi-frequency PELDOR time traces of all doubly Ç-labelled samples simultaneously. This ensemble reflects the global structure and the conformational flexibility of the two-way DNA junction. We demonstrate this approach on a flexible bent DNA molecule, consisting of two short helical parts with a five adenine bulge at the center. The kink and twist motions between both helical parts were quantitatively determined and showed high flexibility, in agreement with a Förster Resonance Energy Transfer (FRET) study on a similar bent DNA motif. The approach presented here should be useful to describe the relative orientation of helical motifs and the conformational flexibility of nucleic acid structures, both alone and in complexes with proteins and other molecules.

Flexible attention allocation to visual and auditory working memory tasks: manipulating reward induces a trade-off.

PubMed

Morey, Candice Coker; Cowan, Nelson; Morey, Richard D; Rouder, Jeffery N

2011-02-01

Prominent roles for general attention resources are posited in many models of working memory, but the manner in which these can be allocated differs between models or is not sufficiently specified. We varied the payoffs for correct responses in two temporally-overlapping recognition tasks, a visual array comparison task and a tone sequence comparison task. In the critical conditions, an increase in reward for one task corresponded to a decrease in reward for the concurrent task, but memory load remained constant. Our results show patterns of interference consistent with a trade-off between the tasks, suggesting that a shared resource can be flexibly divided, rather than only fully allotted to either of the tasks. Our findings support a role for a domain-general resource in models of working memory, and furthermore suggest that this resource is flexibly divisible.

Task oriented nonlinear control laws for telerobotic assembly operations

NASA Technical Reports Server (NTRS)

Walker, R. A.; Ward, L. S.; Elia, C. F.

1987-01-01

The goal of this research is to achieve very intelligent telerobotic controllers which are capable of receiving high-level commands from the human operator and implementing them in an adaptive manner in the object/task/manipulator workspace. Initiatives by the authors at Integrated Systems, Inc. to identify and develop the key technologies necessary to create such a flexible, highly programmable, telerobotic controller are presented. The focus of the discussion is on the modeling of insertion tasks in three dimensions and nonlinear implicit force feedback control laws which incorporate tool/workspace constraints. Preliminary experiments with dual arm beam assembly in 2-D are presented.

Italian version of the task and ego orientation in sport questionnaire.

PubMed

Bortoli, Laura; Robazza, Claudio

2005-02-01

The 1992 Task and Ego Orientation in Sport Questionnaire developed by Duda and Nicholls was translated into Italian and administered to 802 young athletes, 248 girls and 554 boys aged 8 to 14 years, drawn from a range of individual and team sports, to examine its factor structure. Data sets of a calibration sample (boys 12-14 years) and of four cross-validation samples (boys 8-11 years, girls 8-11 years, boys 12-14 years, and girls 12-14 years) were subjected to confirmatory factor analysis specifying, as in the original questionnaire, an Ego Orientation scale (6 items) and a Task Orientation scale (7 items). Results across sex and age yielded chi2/df ratios ranging from 1.95 to 3.57, GFI indices above .90, AGFI indices ranging from .90 to .92, and RMSEA values not above .10. Findings provided acceptable support for the two-dimension structure of the test. In the whole sample, the Ego factor accounted for the 27.2% of variance and the Task factor accounted for the 33.5% of variance. Acceptable internal consistency of the two scales was also shown, with Cronbach alpha values ranging from .73 to .85.

Interaction between Task Oriented and Affective Information Processing in Cognitive Robotics

NASA Astrophysics Data System (ADS)

Haazebroek, Pascal; van Dantzig, Saskia; Hommel, Bernhard

There is an increasing interest in endowing robots with emotions. Robot control however is still often very task oriented. We present a cognitive architecture that allows the combination of and interaction between task representations and affective information processing. Our model is validated by comparing simulation results with empirical data from experimental psychology.

Ground/Air Task Oriented Radar (G/ATOR)

DTIC Science & Technology

2015-12-01

Selected Acquisition Report ( SAR ) RCS: DD-A&T(Q&A)823-386 Ground/Air Task Oriented Radar (G/ATOR) As of FY 2017 President’s Budget Defense...Acquisition Management Information Retrieval (DAMIR) March 18, 2016 06:47:59 UNCLASSIFIED G/ATOR December 2015 SAR March 18, 2016 06:47:59 UNCLASSIFIED 2...Document OSD - Office of the Secretary of Defense O&S - Operating and Support PAUC - Program Acquisition Unit Cost G/ATOR December 2015 SAR March 18

Task Oriented Evaluation of Module Extraction Techniques

NASA Astrophysics Data System (ADS)

Palmisano, Ignazio; Tamma, Valentina; Payne, Terry; Doran, Paul

Ontology Modularization techniques identify coherent and often reusable regions within an ontology. The ability to identify such modules, thus potentially reducing the size or complexity of an ontology for a given task or set of concepts is increasingly important in the Semantic Web as domain ontologies increase in terms of size, complexity and expressivity. To date, many techniques have been developed, but evaluation of the results of these techniques is sketchy and somewhat ad hoc. Theoretical properties of modularization algorithms have only been studied in a small number of cases. This paper presents an empirical analysis of a number of modularization techniques, and the modules they identify over a number of diverse ontologies, by utilizing objective, task-oriented measures to evaluate the fitness of the modules for a number of statistical classification problems.

Task-oriented aerobic exercise in chronic hemiparetic stroke: training protocols and treatment effects.

PubMed

Macko, R F; Ivey, F M; Forrester, L W

2005-01-01

Stroke is the leading cause of disability in older Americans. Each year 750,000 Americans suffer a stroke, two thirds of whom are left with neurological deficits that persistently impair function. Principal among them is hemiparetic gait that limits mobility and increases fall risk, promoting a sedentary lifestyle. These events propagate disability by physical deconditioning and "learned non-use," with further functional declines accelerated by the sarcopenia and fitness decrements of advancing age. Conventional rehabilitation care typically provides little or no structured therapeutic exercise beyond the subacute stroke recovery period, based on natural history studies showing little or no further functional motor recovery beyond 6 months after stroke. Emerging evidence suggests that new models of task-oriented exercise have the potential to improve motor function even years after stroke. This article presents treadmill as a task-oriented training paradigm to optimize locomotor relearning while eliciting cardiovascular conditioning in chronic stroke patients. Protocols for exercise testing and longitudinal aerobic training progression are presented that provide fundamental formulas that safely approach the complex task of customizing aerobic training to gait deficit severity in the high CVD risk stroke population. The beneficial effects of 6 months task-oriented treadmill exercise on cardiovascular-metabolic fitness, energy cost of hemiparetic gait, ADL mobility task performance, and leg strength are discussed with respect to the central and peripheral neuromuscular adaptations targeted by the training. Collectively, these findings constitute one initial experience in a much broader neuroscience and exercise rehabilitation development of task-oriented training paradigms that offer a multisystems approach to improving both neurological and cardiovascular health outcomes in the chronic stroke population.

Cognitive caching promotes flexibility in task switching: evidence from event-related potentials.

PubMed

Lange, Florian; Seer, Caroline; Müller, Dorothea; Kopp, Bruno

2015-12-08

Time-consuming processes of task-set reconfiguration have been shown to contribute to the costs of switching between cognitive tasks. We describe and probe a novel mechanism serving to reduce the costs of task-set reconfiguration. We propose that when individuals are uncertain about the currently valid task, one task set is activated for execution while other task sets are maintained at a pre-active state in cognitive cache. We tested this idea by assessing an event-related potential (ERP) index of task-set reconfiguration in a three-rule task-switching paradigm involving varying degrees of task uncertainty. In high-uncertainty conditions, two viable tasks were equally likely to be correct whereas in low-uncertainty conditions, one task was more likely than the other. ERP and performance measures indicated substantial costs of task-set reconfiguration when participants were required to switch away from a task that had been likely to be correct. In contrast, task-set-reconfiguration costs were markedly reduced when the previous task set was chosen under high task uncertainty. These results suggest that cognitive caching of alternative task sets adds to human cognitive flexibility under high task uncertainty.

Cognitive caching promotes flexibility in task switching: evidence from event-related potentials

PubMed Central

Lange, Florian; Seer, Caroline; Müller, Dorothea; Kopp, Bruno

2015-01-01

Time-consuming processes of task-set reconfiguration have been shown to contribute to the costs of switching between cognitive tasks. We describe and probe a novel mechanism serving to reduce the costs of task-set reconfiguration. We propose that when individuals are uncertain about the currently valid task, one task set is activated for execution while other task sets are maintained at a pre-active state in cognitive cache. We tested this idea by assessing an event-related potential (ERP) index of task-set reconfiguration in a three-rule task-switching paradigm involving varying degrees of task uncertainty. In high-uncertainty conditions, two viable tasks were equally likely to be correct whereas in low-uncertainty conditions, one task was more likely than the other. ERP and performance measures indicated substantial costs of task-set reconfiguration when participants were required to switch away from a task that had been likely to be correct. In contrast, task-set-reconfiguration costs were markedly reduced when the previous task set was chosen under high task uncertainty. These results suggest that cognitive caching of alternative task sets adds to human cognitive flexibility under high task uncertainty. PMID:26643146

Children's Performance in Mental Rotation Tasks: Orientation-Free Features Flatten the Slope

ERIC Educational Resources Information Center

Perrucci, Vittore; Agnoli, Franca; Albiero, Paolo

2008-01-01

Studies of the development of mental rotation have yielded conflicting results, apparently because different mental rotation tasks draw on different cognitive abilities. Children may compare two stimuli at different orientations without mental rotation if the stimuli contain orientation-free features. Two groups of children (78 6-year-olds and 92…

Feature-selective Attention in Frontoparietal Cortex: Multivoxel Codes Adjust to Prioritize Task-relevant Information.

PubMed

Jackson, Jade; Rich, Anina N; Williams, Mark A; Woolgar, Alexandra

2017-02-01

Human cognition is characterized by astounding flexibility, enabling us to select appropriate information according to the objectives of our current task. A circuit of frontal and parietal brain regions, often referred to as the frontoparietal attention network or multiple-demand (MD) regions, are believed to play a fundamental role in this flexibility. There is evidence that these regions dynamically adjust their responses to selectively process information that is currently relevant for behavior, as proposed by the "adaptive coding hypothesis" [Duncan, J. An adaptive coding model of neural function in prefrontal cortex. Nature Reviews Neuroscience, 2, 820-829, 2001]. Could this provide a neural mechanism for feature-selective attention, the process by which we preferentially process one feature of a stimulus over another? We used multivariate pattern analysis of fMRI data during a perceptually challenging categorization task to investigate whether the representation of visual object features in the MD regions flexibly adjusts according to task relevance. Participants were trained to categorize visually similar novel objects along two orthogonal stimulus dimensions (length/orientation) and performed short alternating blocks in which only one of these dimensions was relevant. We found that multivoxel patterns of activation in the MD regions encoded the task-relevant distinctions more strongly than the task-irrelevant distinctions: The MD regions discriminated between stimuli of different lengths when length was relevant and between the same objects according to orientation when orientation was relevant. The data suggest a flexible neural system that adjusts its representation of visual objects to preferentially encode stimulus features that are currently relevant for behavior, providing a neural mechanism for feature-selective attention.

Trajectory-Oriented Approach to Managing Traffic Complexity: Trajectory Flexibility Metrics and Algorithms and Preliminary Complexity Impact Assessment

NASA Technical Reports Server (NTRS)

Idris, Husni; Vivona, Robert A.; Al-Wakil, Tarek

2009-01-01

This document describes exploratory research on a distributed, trajectory oriented approach for traffic complexity management. The approach is to manage traffic complexity based on preserving trajectory flexibility and minimizing constraints. In particular, the document presents metrics for trajectory flexibility; a method for estimating these metrics based on discrete time and degree of freedom assumptions; a planning algorithm using these metrics to preserve flexibility; and preliminary experiments testing the impact of preserving trajectory flexibility on traffic complexity. The document also describes an early demonstration capability of the trajectory flexibility preservation function in the NASA Autonomous Operations Planner (AOP) platform.

An Efficient Framework for Development of Task-Oriented Dialog Systems in a Smart Home Environment.

PubMed

Park, Youngmin; Kang, Sangwoo; Seo, Jungyun

2018-05-16

In recent times, with the increasing interest in conversational agents for smart homes, task-oriented dialog systems are being actively researched. However, most of these studies are focused on the individual modules of such a system, and there is an evident lack of research on a dialog framework that can integrate and manage the entire dialog system. Therefore, in this study, we propose a framework that enables the user to effectively develop an intelligent dialog system. The proposed framework ontologically expresses the knowledge required for the task-oriented dialog system's process and can build a dialog system by editing the dialog knowledge. In addition, the framework provides a module router that can indirectly run externally developed modules. Further, it enables a more intelligent conversation by providing a hierarchical argument structure (HAS) to manage the various argument representations included in natural language sentences. To verify the practicality of the framework, an experiment was conducted in which developers without any previous experience in developing a dialog system developed task-oriented dialog systems using the proposed framework. The experimental results show that even beginner dialog system developers can develop a high-level task-oriented dialog system.

An Efficient Framework for Development of Task-Oriented Dialog Systems in a Smart Home Environment

PubMed Central

Park, Youngmin; Kang, Sangwoo; Seo, Jungyun

2018-01-01

In recent times, with the increasing interest in conversational agents for smart homes, task-oriented dialog systems are being actively researched. However, most of these studies are focused on the individual modules of such a system, and there is an evident lack of research on a dialog framework that can integrate and manage the entire dialog system. Therefore, in this study, we propose a framework that enables the user to effectively develop an intelligent dialog system. The proposed framework ontologically expresses the knowledge required for the task-oriented dialog system’s process and can build a dialog system by editing the dialog knowledge. In addition, the framework provides a module router that can indirectly run externally developed modules. Further, it enables a more intelligent conversation by providing a hierarchical argument structure (HAS) to manage the various argument representations included in natural language sentences. To verify the practicality of the framework, an experiment was conducted in which developers without any previous experience in developing a dialog system developed task-oriented dialog systems using the proposed framework. The experimental results show that even beginner dialog system developers can develop a high-level task-oriented dialog system. PMID:29772668

Uncertainty Modeling and Evaluation of CMM Task Oriented Measurement Based on SVCMM

NASA Astrophysics Data System (ADS)

Li, Hongli; Chen, Xiaohuai; Cheng, Yinbao; Liu, Houde; Wang, Hanbin; Cheng, Zhenying; Wang, Hongtao

2017-10-01

Due to the variety of measurement tasks and the complexity of the errors of coordinate measuring machine (CMM), it is very difficult to reasonably evaluate the uncertainty of the measurement results of CMM. It has limited the application of CMM. Task oriented uncertainty evaluation has become a difficult problem to be solved. Taking dimension measurement as an example, this paper puts forward a practical method of uncertainty modeling and evaluation of CMM task oriented measurement (called SVCMM method). This method makes full use of the CMM acceptance or reinspection report and the Monte Carlo computer simulation method (MCM). The evaluation example is presented, and the results are evaluated by the traditional method given in GUM and the proposed method, respectively. The SVCMM method is verified to be feasible and practical. It can help CMM users to conveniently complete the measurement uncertainty evaluation through a single measurement cycle.

Temporal Effects of Alignment in Text-Based, Task-Oriented Discourse

ERIC Educational Resources Information Center

Foltz, Anouschka; Gaspers, Judith; Meyer, Carolin; Thiele, Kristina; Cimiano, Philipp; Stenneken, Prisca

2015-01-01

Communicative alignment refers to adaptation to one's communication partner. Temporal aspects of such alignment have been little explored. This article examines temporal aspects of lexical and syntactic alignment (i.e., tendencies to use the interlocutor's lexical items and syntactic structures) in task-oriented discourse. In particular, we…

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

NASA Astrophysics Data System (ADS)

Nightingale, James; Wang, Qi; Grecos, Christos

2015-02-01

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

Dynamic Trial-by-Trial Recoding of Task-Set Representations in the Frontoparietal Cortex Mediates Behavioral Flexibility

PubMed Central

Qiao, Lei; Zhang, Lijie

2017-01-01

Cognitive flexibility forms the core of the extraordinary ability of humans to adapt, but the precise neural mechanisms underlying our ability to nimbly shift between task sets remain poorly understood. Recent functional magnetic resonance imaging (fMRI) studies employing multivoxel pattern analysis (MVPA) have shown that a currently relevant task set can be decoded from activity patterns in the frontoparietal cortex, but whether these regions support the dynamic transformation of task sets from trial to trial is not clear. Here, we combined a cued task-switching protocol with human (both sexes) fMRI, and harnessed representational similarity analysis (RSA) to facilitate a novel assessment of trial-by-trial changes in neural task-set representations. We first used MVPA to define task-sensitive frontoparietal and visual regions and found that neural task-set representations on switch trials are less stably encoded than on repeat trials. We then exploited RSA to show that the neural representational pattern dissimilarity across consecutive trials is greater for switch trials than for repeat trials, and that the degree of this pattern dissimilarity predicts behavior. Moreover, the overall neural pattern of representational dissimilarities followed from the assumption that repeating sets, compared with switching sets, results in stronger neural task representations. Finally, when moving from cue to target phase within a trial, pattern dissimilarities tracked the transformation from previous-trial task representations to the currently relevant set. These results provide neural evidence for the longstanding assumptions of an effortful task-set reconfiguration process hampered by task-set inertia, and they demonstrate that frontoparietal and stimulus processing regions support “dynamic adaptive coding,” flexibly representing changing task sets in a trial-by-trial fashion. SIGNIFICANCE STATEMENT Humans can fluently switch between different tasks, reflecting an ability

Alpha-power modulation reflects the balancing of task requirements in a selective attention task.

PubMed

Limbach, Katharina; Corballis, Paul M

2017-02-01

Recent research has related the orienting of selective attention to the lateralization of posterior EEG alpha power (∼8 to 12 Hz). Typically, alpha power decreases over the side of the head contralateral to the cued side of space. However, it is not clear how this lateralization affects behavior. We recorded EEG from 20 participants while they performed a cued visual discrimination task under three different response-deadline conditions to investigate the effect of alpha-power modulation on behavioral performance in more detail. Although all participants benefited from the cue behaviorally and adjusted their performance according to the response deadlines, we found the cue-related alpha-power modulation to depend on the general alpha-power level at baseline: Only participants with high baseline alpha power showed significant cue-related alpha-power lateralization that was, however, strikingly similar across response-deadline conditions. On the other hand, participants with low alpha power at baseline did not show any lateralization, but adjusted their alpha levels according to the response-deadline instructions and, more importantly, showed a stronger influence of the task instructions on behavioral performance and adapted their response accuracies to the task requirements more flexibly. These findings challenge the often-assumed role of alpha-power lateralization for attentional deployment. While alpha power seems to be related to behavioral performance and the orienting of attention, this relationship is rather complex and, at least under the current task requirements, the general alpha-power state seems to be more strongly related to behavioral performance (in our case, the flexible adjustment to task requirements) than the cue-related lateralization. © 2016 Society for Psychophysiological Research.

Mechanism Design for Task Procurement with Flexible Quality of Service

NASA Astrophysics Data System (ADS)

Gerding, Enrico H.; Larson, Kate; Rogers, Alex; Jennings, Nicholas R.

In this paper, we consider the problem where an agent wishes to complete a single computational task, but lacks the required resources. Instead, it must contract self-interested service providers, who are able to flexibly manipulate the quality of service they deliver, in order to maximise their own utility. We extend an existing model to allow for multiple such service providers to be contracted for the same task, and derive optimal task procurement mechanisms in the setting where the agent has full knowledge of the cost functions of these service providers (considering both simultaneous and sequential procurement). We then extend these results to the incomplete information setting where the agent must elicit cost information from the service providers, and we characterise a family of incentive-compatible and individually-rational mechanisms. We show empirically that sequential procurement always generates greater utility for the agent compared to simultaneous procurement, and that over a range of settings, contracting multiple providers is preferable to contracting just one.

The influence of visual and vestibular orientation cues in a clock reading task.

PubMed

Davidenko, Nicolas; Cheong, Yeram; Waterman, Amanda; Smith, Jacob; Anderson, Barrett; Harmon, Sarah

2018-05-23

We investigated how performance in the real-life perceptual task of analog clock reading is influenced by the clock's orientation with respect to egocentric, gravitational, and visual-environmental reference frames. In Experiment 1, we designed a simple clock-reading task and found that observers' reaction time to correctly tell the time depends systematically on the clock's orientation. In Experiment 2, we dissociated egocentric from environmental reference frames by having participants sit upright or lie sideways while performing the task. We found that both reference frames substantially contribute to response times in this task. In Experiment 3, we placed upright or rotated participants in an upright or rotated immersive virtual environment, which allowed us to further dissociate vestibular from visual cues to the environmental reference frame. We found evidence of environmental reference frame effects only when visual and vestibular cues were aligned. We discuss the implications for the design of remote and head-mounted displays. Copyright © 2018 Elsevier Inc. All rights reserved.

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

PubMed

Olfers, Kerwin J F; Band, Guido P H

2018-01-01

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

Children's Task Oriented Patterns in Early Childhood: A Latent Transition Analysis

ERIC Educational Resources Information Center

Wang, Feihong; Algina, James; Snyder, Patricia; Cox, Martha; Vernon-Feagans, Lynne; Cox, Martha; Blair, Clancy; Burchinal, Margaret; Burton, Linda; Crnic, Keith; Crouter, Ann; Garrett-Peters, Patricia; Greenberg, Mark; Lanza, Stephanie; Mills-Koonce, Roger; Werner, Emily; Willoughby, Michael

2017-01-01

We examined individual differences and predictions of children's patterns in behavioral, emotional and attentional efforts toward challenging puzzle tasks at 24 and 35 months using data from a large longitudinal rural representative sample. Using latent transition analysis, we found four distinct task-oriented patterns in problem-solving tasks…

Bilateral robotic priming before task-oriented approach in subacute stroke rehabilitation: a pilot randomized controlled trial.

PubMed

Hsieh, Yu-Wei; Wu, Ching-Yi; Wang, Wei-En; Lin, Keh-Chung; Chang, Ku-Chou; Chen, Chih-Chi; Liu, Chien-Ting

2017-02-01

To investigate the treatment effects of bilateral robotic priming combined with the task-oriented approach on motor impairment, disability, daily function, and quality of life in patients with subacute stroke. A randomized controlled trial. Occupational therapy clinics in medical centers. Thirty-one subacute stroke patients were recruited. Participants were randomly assigned to receive bilateral priming combined with the task-oriented approach (i.e., primed group) or to the task-oriented approach alone (i.e., unprimed group) for 90 minutes/day, 5 days/week for 4 weeks. The primed group began with the bilateral priming technique by using a bimanual robot-aided device. Motor impairments were assessed by the Fugal-Meyer Assessment, grip strength, and the Box and Block Test. Disability and daily function were measured by the modified Rankin Scale, the Functional Independence Measure, and actigraphy. Quality of life was examined by the Stroke Impact Scale. The primed and unprimed groups improved significantly on most outcomes over time. The primed group demonstrated significantly better improvement on the Stroke Impact Scale strength subscale ( p = 0.012) and a trend for greater improvement on the modified Rankin Scale ( p = 0.065) than the unprimed group. Bilateral priming combined with the task-oriented approach elicited more improvements in self-reported strength and disability degrees than the task-oriented approach by itself. Further large-scale research with at least 31 participants in each intervention group is suggested to confirm the study findings.

Career-Oriented Performance Tasks: Effects on Students' Interest in Chemistry

ERIC Educational Resources Information Center

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

2013-01-01

The study was conducted to assess the effectiveness of Career-Oriented Performance Task (COPT) approach against the traditional teaching approach (TTA) in enhancing students' interest in Chemistry. Specifically, it sought to find out if students exposed to COPT have higher interest in Chemistry than those students exposed to the traditional…

Sexual orientation differences in cerebral asymmetry and in the performance of sexually dimorphic cognitive and motor tasks.

PubMed

Sanders, G; Wright, M

1997-10-01

With each of the tasks in the present studies we expected to find the reported sex difference between heterosexual women and heterosexual men and we predicted a sexual orientation effect with the performance of homosexual men being similar to that of heterosexual women and different from that of heterosexual men. Study 1 aimed to replicate earlier findings by recording the performance of a group of homosexual men on a visuospatial task, the Vincent Mechanical Diagrams Test (VMDT), a dot detection divided visual field measure of functional cerebral asymmetry, and on five subtests of the Wechsler Adult Intelligence Scale (WAIS). For each task the profile of scores obtained for the homosexual men was similar to that of heterosexual women in that they scored lower than heterosexual men on the VMDT, they showed less asymmetry, and they recorded a higher Verbal than Performance IQ on the WAIS. In Study 2, a male-biased targeted throwing task favored heterosexual men while, in contrast, on the female-biased Purdue Pegboard single peg condition heterosexual men were outperformed by heterosexual women and homosexual men. On neither of these two tasks did the performances of homosexual men and heterosexual women differ. One task, manual speed, yielded neither sex nor sexual orientation differences. Another, the Purdue Pegboard assemblies condition, revealed a sex difference but no sexual orientation difference. Failure to obtain a sexual orientation difference in the presence of a sex difference suggests that the sexual orientation effect may be restricted to a subset of sexually dimorphic tasks.

Flexibility of orthographic and graphomotor coordination during a handwritten copy task: effect of time pressure

PubMed Central

Sausset, Solen; Lambert, Eric; Olive, Thierry

2013-01-01

The coordination of the various processes involved in language production is a subject of keen debate in writing research. Some authors hold that writing processes can be flexibly coordinated according to task demands, whereas others claim that process coordination is entirely inflexible. For instance, orthographic planning has been shown to be resource-dependent during handwriting, but inflexible in typing, even under time pressure. The present study therefore went one step further in studying flexibility in the coordination of orthographic processing and graphomotor execution, by measuring the impact of time pressure during a handwritten copy task. Orthographic and graphomotor processes were observed via syllable processing. Writers copied out two- and three-syllable words three times in a row, with and without time pressure. Latencies and letter measures at syllable boundaries were analyzed. We hypothesized that if coordination is flexible and varies according to task demands, it should be modified by time pressure, affecting both latency before execution and duration of execution. We therefore predicted that the extent of syllable processing before execution would be reduced under time pressure and, as a consequence, syllable effects during execution would be more salient. Results showed, however, that time pressure interacted neither with syllable number nor with syllable structure. Accordingly, syllable processing appears to remain the same regardless of time pressure. The flexibility of process coordination during handwriting is discussed, as is the operationalization of time pressure constraints. PMID:24319435

Flexible and inflexible task sets: asymmetric interference when switching between emotional expression, sex, and age classification of perceived faces.

PubMed

Schuch, Stefanie; Werheid, Katja; Koch, Iring

2012-01-01

The present study investigated whether the processing characteristics of categorizing emotional facial expressions are different from those of categorizing facial age and sex information. Given that emotions change rapidly, it was hypothesized that processing facial expressions involves a more flexible task set that causes less between-task interference than the task sets involved in processing age or sex of a face. Participants switched between three tasks: categorizing a face as looking happy or angry (emotion task), young or old (age task), and male or female (sex task). Interference between tasks was measured by global interference and response interference. Both measures revealed patterns of asymmetric interference. Global between-task interference was reduced when a task was mixed with the emotion task. Response interference, as measured by congruency effects, was larger for the emotion task than for the nonemotional tasks. The results support the idea that processing emotional facial expression constitutes a more flexible task set that causes less interference (i.e., task-set "inertia") than processing the age or sex of a face.

Semiconductor-based, large-area, flexible, electronic devices on {110}<100> oriented substrates

DOEpatents

Goyal, Amit

2014-08-05

Novel articles and methods to fabricate the same resulting in flexible, oriented, semiconductor-based, electronic devices on {110}<100> textured substrates are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

Italian version of the Task and Ego Orientation in physical education questionnaire.

PubMed

Bortoli, Laura; Robazza, Claudio

2005-12-01

The 1992 Task and Ego Orientation in Sport Questionnaire developed by Duda and Nicholls was modified by Walling and Duda in 1995 to assess task and ego orientation in physical education. The modified version was translated into Italian and administered to 1,547 students, 786 girls and 761 boys ages 14 to 19 years, to examine the factor structure. To evaluate the goodness of fit of the expected two-factor solution as in the original questionnaire, confirmatory factor analysis was conducted on four samples of boys and girls of two classes of age (14-16 and 17-19 years). Across sex and age, chi-squared/df ratios were less than 5.0, fit indices (GFI, NNFI, and CFI) not less than .90, and root mean square error of approximation (RMSEA) below .10. Thus, the two-factor solution of the questionnaire was supported. In the total sample, the two scales showed good internal consistency, with Cronbach alpha values of .92 for the Ego factor and .83 for the Task factor. The Ego factor accounted for 34.1% of variance and the Task factor accounted for 21.0% of variance.

The Opposites Task: Using General Rules to Test Cognitive Flexibility in Preschoolers

ERIC Educational Resources Information Center

Baker, Sara T.; Friedman, Ori; Leslie, Alan M.

2010-01-01

Executive functions play an important role in cognitive development, and during the preschool years especially, children's performance is limited in tasks that demand flexibility in their behavior. We asked whether preschoolers would exhibit limitations when they are required to apply a general rule in the context of novel stimuli on every trial…

No role of beta receptors in cognitive flexibility: Evidence from a task-switching paradigm in a randomized controlled trial.

PubMed

Steenbergen, L; Sellaro, R; de Rover, M; Hommel, B; Colzato, L S

2015-06-04

There is evidence that noradrenergic coeruleo-cortical projections are involved in different forms of cognitive flexibility. So far, no studies in humans have investigated the involvement of beta receptors on task-switching performance, a well-established measure of cognitive flexibility. The present study investigated whether the administration of propranolol (a central and peripheral beta-adrenergic antagonist) affected switching costs (i.e., the increase of reaction time in task-switching trials relative to task-repetition trials). Sixteen healthy adult human subjects performed a global-local task-switching paradigm in a double-blind, within-subjects design study investigating the effects of 80mg of propranolol hydrochloride (a β1 and β2 adrenergic receptor antagonist) vs. an oral dose of microcrystalline cellulose (placebo pill). The acute administration of propranolol did not affect the size of switching costs compared to the intake of the neutral placebo. Our results, corroborated by Bayesian inference, suggest that beta receptors do not modulate cognitive flexibility as measured by task-switching performance. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Web-Based Seamless Migration for Task-Oriented Mobile Distance Learning

ERIC Educational Resources Information Center

Zhang, Degan; Li, Yuan-chao; Zhang, Huaiyu; Zhang, Xinshang; Zeng, Guangping

2006-01-01

As a new kind of computing paradigm, pervasive computing will meet the requirements of human being that anybody maybe obtain services in anywhere and at anytime, task-oriented seamless migration is one of its applications. Apparently, the function of seamless mobility is suitable for mobile services, such as mobile Web-based learning. In this…

A flexible influence of affective feelings on creative and analytic performance.

PubMed

Huntsinger, Jeffrey R; Ray, Cara

2016-09-01

Considerable research shows that positive affect improves performance on creative tasks and negative affect improves performance on analytic tasks. The present research entertained the idea that affective feelings have flexible, rather than fixed, effects on cognitive performance. Consistent with the idea that positive and negative affect signal the value of accessible processing inclinations, the influence of affective feelings on performance on analytic or creative tasks was found to be flexibly responsive to the relative accessibility of different styles of processing (i.e., heuristic vs. systematic, global vs. local). When a global processing orientation was accessible happy participants generated more creative uses for a brick (Experiment 1), successfully solved more remote associates and insight problems (Experiment 2) and displayed broader categorization (Experiment 3) than those in sad moods. When a local processing orientation was accessible this pattern reversed. When a heuristic processing style was accessible happy participants were more likely to commit the conjunction fallacy (Experiment 3) and showed less pronounced anchoring effects (Experiment 4) than sad participants. When a systematic processing style was accessible this pattern reversed. Implications of these results for relevant affect-cognition models are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A Flexible Question-and-Answer Task for Measuring Speech Understanding

PubMed Central

Streeter, Timothy; Roverud, Elin; Mason, Christine R.; Kidd, Gerald

2016-01-01

This report introduces a new speech task based on simple questions and answers. The task differs from a traditional sentence recall task in that it involves an element of comprehension and can be implemented in an ongoing fashion. It also contains two target items (the question and the answer) that may be associated with different voices and locations to create dynamic listening scenarios. A set of 227 questions was created, covering six broad categories (days of the week, months of the year, numbers, colors, opposites, and sizes). All questions and their one-word answers were spoken by 11 female and 11 male talkers. In this study, listeners were presented with question-answer pairs and asked to indicate whether the answer was true or false. Responses were given as simple button or key presses, which are quick to make and easy to score. Two preliminary experiments are presented that illustrate different ways of implementing the basic task. In the first experiment, question-answer pairs were presented in speech-shaped noise, and performance was compared across subjects, question categories, and time, to examine the different sources of variability. In the second experiment, sequences of question-answer pairs were presented amidst competing conversations in an ongoing, spatially dynamic listening scenario. Overall, the question-and-answer task appears to be feasible and could be implemented flexibly in a number of different ways. PMID:27888257

Task Delegation Based Access Control Models for Workflow Systems

NASA Astrophysics Data System (ADS)

Gaaloul, Khaled; Charoy, François

e-Government organisations are facilitated and conducted using workflow management systems. Role-based access control (RBAC) is recognised as an efficient access control model for large organisations. The application of RBAC in workflow systems cannot, however, grant permissions to users dynamically while business processes are being executed. We currently observe a move away from predefined strict workflow modelling towards approaches supporting flexibility on the organisational level. One specific approach is that of task delegation. Task delegation is a mechanism that supports organisational flexibility, and ensures delegation of authority in access control systems. In this paper, we propose a Task-oriented Access Control (TAC) model based on RBAC to address these requirements. We aim to reason about task from organisational perspectives and resources perspectives to analyse and specify authorisation constraints. Moreover, we present a fine grained access control protocol to support delegation based on the TAC model.

A simple method for orienting silk and other flexible fibres in transmission electron microscopy specimens.

PubMed

Trancik, J E; Czernuszka, J T; Merriman, C; Viney, C

2001-09-01

When microstructures are characterized by transmission electron microscopy (TEM), the interpretation of results is facilitated if the material can be sectioned in defined orientations. In the case of fibres, it is especially useful if transverse and longitudinal sections can be obtained reliably. Here we describe a procedure for orienting spider silk and other flexible fibres for TEM investigation. Prior to embedding in epoxy resin, the silk is wound around a notched support made from polyester film. No glue is required. After the silk and its supporting film have been embedded and the resin has been cured the film can be peeled away to reveal nearly perfectly orientated silk threads. Both transverse and longitudinal sections can then be cut with a microtome. The method can be extended to obtain sections at any intermediate orientation.

Optogenetic silencing of locus coeruleus activity in mice impairs cognitive flexibility in an attentional set-shifting task

PubMed Central

Janitzky, Kathrin; Lippert, Michael T.; Engelhorn, Achim; Tegtmeier, Jennifer; Goldschmidt, Jürgen; Heinze, Hans-Jochen; Ohl, Frank W.

2015-01-01

The locus coeruleus (LC) is the sole source of noradrenergic projections to the cortex and essential for attention-dependent cognitive processes. In this study we used unilateral optogenetic silencing of the LC in an attentional set-shifting task (ASST) to evaluate the influence of the LC on prefrontal cortex-dependent functions in mice. We expressed the halorhodopsin eNpHR 3.0 to reversibly silence LC activity during task performance, and found that silencing selectively impaired learning of those parts of the ASST that most strongly rely on cognitive flexibility. In particular, extra-dimensional set-shifting (EDS) and reversal learning was impaired, suggesting an involvement of the medial prefrontal cortex (mPFC) and the orbitofrontal cortex. In contrast, those parts of the task that are less dependent on cognitive flexibility, i.e., compound discrimination (CD) and the intra-dimensional shifts (IDS) were not affected. Furthermore, attentional set formation was unaffected by LC silencing. Our results therefore suggest a modulatory influence of the LC on cognitive flexibility, mediated by different frontal networks. PMID:26582980

Small, Task-Oriented Groups: Conflict, Conflict Management, Satisfaction, and Decision Quality.

ERIC Educational Resources Information Center

Wall, Victor D., Jr.; And Others

1987-01-01

Examined relationship among amount of conflict experienced, the style of its management, individual satisfaction, and decision quality of small, task-oriented groups using 129 college student subjects in 24 groups. Data suggest a curvilinear relationship between the number of conflict episodes experienced by group members and the subsequent…

Mirror Therapy and Task-Oriented Training for People With a Paretic Upper Extremity.

PubMed

Bondoc, Salvador; Booth, Julie; Budde, Grace; Caruso, Katelyn; DeSousa, Michelle; Earl, Brittany; Hammerton, Kaitlynn; Humphreys, Jill

This study investigates the effect of mirror therapy and task-oriented training on the paretic upper extremity function and occupational performance of people with stroke. This study used a repeated-measures, case-series design in which 4 participants completed a 4-wk intervention consisting of mirror therapy and task-specific training. The intervention was conducted 2×/wk in the clinic and 4×/wk at home. All participants displayed clinically meaningful improvements in self-identified goals at the end of the intervention and at follow-up. Three participants showed clinically meaningful changes in motor function. Although only 1 participant improved in his reported amount of use, all participants showed clinically meaningful improvements in perceived movement quality at varying points of assessment. Mirror therapy, when used as priming for task-oriented training, can produce clinical improvements in upper extremity function and occupational performance in people with hemiparesis. Copyright © 2018 by the American Occupational Therapy Association, Inc.

Cognitive structure, flexibility, and plasticity in human multitasking-An integrative review of dual-task and task-switching research.

PubMed

Koch, Iring; Poljac, Edita; Müller, Hermann; Kiesel, Andrea

2018-06-01

Numerous studies showed decreased performance in situations that require multiple tasks or actions relative to appropriate control conditions. Because humans often engage in such multitasking activities, it is important to understand how multitasking affects performance. In the present article, we argue that research on dual-task interference and sequential task switching has proceeded largely separately using different experimental paradigms and methodology. In our article we aim at organizing this complex set of research in terms of three complementary research perspectives on human multitasking. One perspective refers to structural accounts in terms of cognitive bottlenecks (i.e., critical processing stages). A second perspective refers to cognitive flexibility in terms of the underlying cognitive control processes. A third perspective emphasizes cognitive plasticity in terms of the influence of practice on human multitasking abilities. With our review article we aimed at highlighting the value of an integrative position that goes beyond isolated consideration of a single theoretical research perspective and that broadens the focus from single experimental paradigms (dual task and task switching) to favor instead a view that emphasizes the fundamental similarity of the underlying cognitive mechanisms across multitasking paradigms. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

An Agent-Based Simulation for Investigating the Impact of Stereotypes on Task-Oriented Group Formation

NASA Astrophysics Data System (ADS)

Maghami, Mahsa; Sukthankar, Gita

In this paper, we introduce an agent-based simulation for investigating the impact of social factors on the formation and evolution of task-oriented groups. Task-oriented groups are created explicitly to perform a task, and all members derive benefits from task completion. However, even in cases when all group members act in a way that is locally optimal for task completion, social forces that have mild effects on choice of associates can have a measurable impact on task completion performance. In this paper, we show how our simulation can be used to model the impact of stereotypes on group formation. In our simulation, stereotypes are based on observable features, learned from prior experience, and only affect an agent's link formation preferences. Even without assuming stereotypes affect the agents' willingness or ability to complete tasks, the long-term modifications that stereotypes have on the agents' social network impair the agents' ability to form groups with sufficient diversity of skills, as compared to agents who form links randomly. An interesting finding is that this effect holds even in cases where stereotype preference and skill existence are completely uncorrelated.

A Flexible Question-and-Answer Task for Measuring Speech Understanding.

PubMed

Best, Virginia; Streeter, Timothy; Roverud, Elin; Mason, Christine R; Kidd, Gerald

2016-11-24

This report introduces a new speech task based on simple questions and answers. The task differs from a traditional sentence recall task in that it involves an element of comprehension and can be implemented in an ongoing fashion. It also contains two target items (the question and the answer) that may be associated with different voices and locations to create dynamic listening scenarios. A set of 227 questions was created, covering six broad categories (days of the week, months of the year, numbers, colors, opposites, and sizes). All questions and their one-word answers were spoken by 11 female and 11 male talkers. In this study, listeners were presented with question-answer pairs and asked to indicate whether the answer was true or false. Responses were given as simple button or key presses, which are quick to make and easy to score. Two preliminary experiments are presented that illustrate different ways of implementing the basic task. In the first experiment, question-answer pairs were presented in speech-shaped noise, and performance was compared across subjects, question categories, and time, to examine the different sources of variability. In the second experiment, sequences of question-answer pairs were presented amidst competing conversations in an ongoing, spatially dynamic listening scenario. Overall, the question-and-answer task appears to be feasible and could be implemented flexibly in a number of different ways. © The Author(s) 2016.

Indirect Measurement of Sexual Orientation: Comparison of the Implicit Relational Assessment Procedure, Viewing Time, and Choice Reaction Time Tasks.

PubMed

Rönspies, Jelena; Schmidt, Alexander F; Melnikova, Anna; Krumova, Rosina; Zolfagari, Asadeh; Banse, Rainer

2015-07-01

The present study was conducted to validate an adaptation of the Implicit Relational Assessment Procedure (IRAP) as an indirect latency-based measure of sexual orientation. Furthermore, reliability and criterion validity of the IRAP were compared to two established indirect measures of sexual orientation: a Choice Reaction Time task (CRT) and a Viewing Time (VT) task. A sample of 87 heterosexual and 35 gay men completed all three indirect measures in an online study. The IRAP and the VT predicted sexual orientation nearly perfectly. Both measures also showed a considerable amount of convergent validity. Reliabilities (internal consistencies) reached satisfactory levels. In contrast, the CRT did not tap into sexual orientation in the present study. In sum, the VT measure performed best, with the IRAP showing only slightly lower reliability and criterion validity, whereas the CRT did not yield any evidence of reliability or criterion validity in the present research. The results were discussed in the light of specific task properties of the indirect latency-based measures (task-relevance vs. task-irrelevance).

Expertise with unfamiliar objects is flexible to changes in task but not changes in class

PubMed Central

Tangen, Jason M.

2017-01-01

Perceptual expertise is notoriously specific and bound by familiarity; generalizing to novel or unfamiliar images, objects, identities, and categories often comes at some cost to performance. In forensic and security settings, however, examiners are faced with the task of discriminating unfamiliar images of unfamiliar objects within their general domain of expertise (e.g., fingerprints, faces, or firearms). The job of a fingerprint expert, for instance, is to decide whether two unfamiliar fingerprint images were left by the same unfamiliar finger (e.g., Smith’s left thumb), or two different unfamiliar fingers (e.g., Smith and Jones’s left thumb). Little is known about the limits of this kind of perceptual expertise. Here, we examine fingerprint experts’ and novices’ ability to distinguish fingerprints compared to inverted faces in two different tasks. Inverted face images serve as an ideal comparison because they vary naturally between and within identities, as do fingerprints, and people tend to be less accurate or more novice-like at distinguishing faces when they are presented in an inverted or unfamiliar orientation. In Experiment 1, fingerprint experts outperformed novices in locating categorical fingerprint outliers (i.e., a loop pattern in an array of whorls), but not inverted face outliers (i.e., an inverted male face in an array of inverted female faces). In Experiment 2, fingerprint experts were more accurate than novices at discriminating matching and mismatching fingerprints that were presented very briefly, but not so for inverted faces. Our data show that perceptual expertise with fingerprints can be flexible to changing task demands, but there can also be abrupt limits: fingerprint expertise did not generalize to an unfamiliar class of stimuli. We interpret these findings as evidence that perceptual expertise with unfamiliar objects is highly constrained by one’s experience. PMID:28574998

Polyaniline-Modified Oriented Graphene Hydrogel Film as the Free-Standing Electrode for Flexible Solid-State Supercapacitors.

PubMed

Du, Pengcheng; Liu, Huckleberry C; Yi, Chao; Wang, Kai; Gong, Xiong

2015-11-04

In this study, we report polyaniline (PANI)-modified oriented graphene hydrogel (OGH) films as the free-standing electrode for flexible solid-state supercapacitors (SCs). The OGH films are prepared by a facile filtration method using chemically converted graphene sheets and then introduced to PANI on the surface of OGH films by in situ chemical polymerization. The PANI-modified OGH films possess high flexibility, high electrical conductivity, and mechanical robustness. The flexible solid-state SCs based on the PANI-modified OGH films exhibit a specific capacitance of 530 F/g, keeping 80% of its original value up to 10 000 charge-discharge cycles at the current density of 10 A/g. Remarkably, the flexible solid-state SCs maintain ∼100% capacitance retention bent at 180° for 250 cycles. Moreover, the flexible solid-state SCs are further demonstrated to be able to light up a red-light-emitting diode. These results indicate that the flexible solid-state SCs based on PANI-modified OGH films as the free-standing electrode have potential applications as energy-storage devices.

Flexible explicit but rigid implicit learning in a visuomotor adaptation task

PubMed Central

Bond, Krista M.

2015-01-01

There is mounting evidence for the idea that performance in a visuomotor rotation task can be supported by both implicit and explicit forms of learning. The implicit component of learning has been well characterized in previous experiments and is thought to arise from the adaptation of an internal model driven by sensorimotor prediction errors. However, the role of explicit learning is less clear, and previous investigations aimed at characterizing the explicit component have relied on indirect measures such as dual-task manipulations, posttests, and descriptive computational models. To address this problem, we developed a new method for directly assaying explicit learning by having participants verbally report their intended aiming direction on each trial. While our previous research employing this method has demonstrated the possibility of measuring explicit learning over the course of training, it was only tested over a limited scope of manipulations common to visuomotor rotation tasks. In the present study, we sought to better characterize explicit and implicit learning over a wider range of task conditions. We tested how explicit and implicit learning change as a function of the specific visual landmarks used to probe explicit learning, the number of training targets, and the size of the rotation. We found that explicit learning was remarkably flexible, responding appropriately to task demands. In contrast, implicit learning was strikingly rigid, with each task condition producing a similar degree of implicit learning. These results suggest that explicit learning is a fundamental component of motor learning and has been overlooked or conflated in previous visuomotor tasks. PMID:25855690

How far will a behaviourally flexible invasive bird go to innovate?

PubMed Central

Logan, Corina J.

2016-01-01

Behavioural flexibility is considered a key factor in the ability to adapt to changing environments. A traditional way of characterizing behavioural flexibility is to determine whether individuals invent solutions to novel problems, termed innovativeness. Great-tailed grackles are behaviourally flexible in that they can change their preferences when a task changes using existing behaviours; however, it is unknown how far they will go to invent solutions to novel problems. To begin to answer this question, I gave grackles two novel tests that a variety of other species can perform: stick tool use and string pulling. No grackle used a stick to access out-of-reach food, even after seeing a human demonstrate the solution. No grackle spontaneously pulled a vertically oriented string, but one did pull a horizontally oriented string twice. Additionally, a third novel test was previously conducted on these individuals and it was found that no grackle spontaneously dropped stones down a platform apparatus to release food, but six out of eight did become proficient after training. These results support the idea that behavioural flexibility is a multi-faceted trait because grackles are flexible, but not particularly innovative. This contradicts the idea that behavioural flexibility and innovativeness are interchangeable terms. PMID:27429781

An Investigation of Task and Ego Oriented Goals of the Students Majoring at the Faculty of Sport Sciences

ERIC Educational Resources Information Center

Belli, Emre

2015-01-01

The aim of this study is to explore the task and ego oriented goals of the students majoring at the Faculty of Sports Sciences at Ataturk University. For data collection, "The Task and Ego Orientation in Sport Questionnaire", which was developed by Duda (1) and adapted into Turkish by Toros and Yetim (2), was used in the current study to…

MSFC personnel management tasks: Recruitment and orientation of new employees

NASA Technical Reports Server (NTRS)

Brindley, T. A.

1980-01-01

In order to encourage highly motivated young students to learn about NASA and consider it for a career, a formal program is to be initiated whereby selected students can work on a voluntary basis at Marshall Space Flight Center (MSFC). The first task was to develop the working plan and procedures for this program, called Student Volunteer Service Program, in the writing of MSFC official guidelines, the Marshall Management Instruction (the MMI) which is a binding document that defines policy and establishes procedures and guidelines. Particular considerations written into the MMI after numerous consultations, interviews, and discussions about a satisfactory policy, include: arrangements to be made between the student, the school authorities, and concerned MSFC employees; management of the work assignments; and procedures for the student's welfare and safety. The second task was the development of a recruitment brochure for the attraction of new employees, especially scientists and engineers. The third task assigned was to develop a plan called Orientation of New Employees.

Effect of hamstring flexibility on hip and lumbar spine joint excursions during forward-reaching tasks in participants with and without low back pain.

PubMed

Johnson, Erica N; Thomas, James S

2010-07-01

To examine the correlation between hamstring flexibility and hip and lumbar spine joint excursions during standardized reaching and forward-bending tasks. Retrospective analysis of data obtained during 2 previous prospective studies that examined kinematics and kinetics during forward-reaching tasks in participants with and without low back pain (LBP). The 2 previous studies were conducted in the Motor Control Lab at Ohio University and the Orthopaedic Ergonomics Laboratory at The Ohio State University. Data from a total of 122 subjects from 2 previous studies: study 1: 86 subjects recovered from an episode of acute LBP (recovered) and study 2 (A.I. McCallum, unpublished data): 18 chronic LBP subjects and 18 healthy-matched controls (healthy). Not applicable. Correlation values between hamstring flexibility as measured by straight leg raise (SLR) and amount of hip and lumbar spine joint excursions used during standardized reaching and forward-bending tasks. No significant correlation was found between hamstring flexibility and hip and lumbar joint excursions during forward-bending tasks in the LBP or recovered groups. The SLR had a significant negative correlation with lumbar spine excursions during reaching tasks to a low target in the healthy group (right SLR: P=.011, left SLR: P=.004). Hamstring flexibility is not strongly related to the amount of lumbar flexion used to perform forward-reaching tasks in participants who have chronic LBP or who have recovered from LBP. More research needs to be conducted to examine the influence of hamstring flexibility on observed movement patterns to further evaluate the efficacy of flexibility training in the rehabilitation of patients with LBP. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Task path planning, scheduling and learning for free-ranging robot systems

NASA Technical Reports Server (NTRS)

Wakefield, G. Steve

1987-01-01

The development of robotics applications for space operations is often restricted by the limited movement available to guided robots. Free ranging robots can offer greater flexibility than physically guided robots in these applications. Presented here is an object oriented approach to path planning and task scheduling for free-ranging robots that allows the dynamic determination of paths based on the current environment. The system also provides task learning for repetitive jobs. This approach provides a basis for the design of free-ranging robot systems which are adaptable to various environments and tasks.

It's All about Baxter: Task Orientation in the Effective Teaching of Writing

ERIC Educational Resources Information Center

Gadd, Murray; Parr, Judy M.

2016-01-01

This New Zealand-based study of the classroom practice of nine exemplary teachers of writing to upper primary-age students explored the significance of task orientation as a component of effective teacher instruction and the instructional strategies or actions that effective teachers utilise to promote such. Effectiveness pertains to teachers…

Effects of task-oriented robot training on arm function, activity, and quality of life in chronic stroke patients: a randomized controlled trial.

PubMed

Timmermans, Annick A A; Lemmens, Ryanne J M; Monfrance, Maurice; Geers, Richard P J; Bakx, Wilbert; Smeets, Rob J E M; Seelen, Henk A M

2014-03-31

Over fifty percent of stroke patients experience chronic arm hand performance problems, compromising independence in daily life activities and quality of life. Task-oriented training may improve arm hand performance after stroke, whereby augmented therapy may lead to a better treatment outcome. Technology-supported training holds opportunities for increasing training intensity. However, the effects of robot-supported task-oriented training with real life objects in stroke patients are not known to date. The aim of the present study was to investigate the effectiveness and added value of the Haptic Master robot combined with task-oriented arm hand training in chronic stroke patients. In a single-blind randomized controlled trial, 22 chronic stroke patients were randomly allocated to receive either task-oriented robot-assisted arm-hand training (experimental group) or task-oriented non-robotic arm-hand training (control group). For training, the T-TOAT (Technology-supported Task-Oriented Arm Training) method was applied. Training was provided during 8 weeks, 4 times/week, 2 × 30 min/day. A significant improvement after training on the Action Research Arm Test (ARAT) was demonstrated in the experimental group (p = 0.008). Results were maintained until 6 months after cessation of the training. On the perceived performance measure (Motor Activity Log (MAL)), both, the experimental and control group improved significantly after training (control group p = 0.008; experimental group p = 0.013). The improvements on MAL in both groups were maintained until 6 months after cessation of the training. With regard to quality of life, only in the control group a significant improvement after training was found (EuroQol-5D p = 0.015, SF-36 physical p = 0.01). However, the improvement on SF-36 in the control group was not maintained (p = 0.012). No between-group differences could be demonstrated on any of the outcome measures. Arm hand performance improved in chronic stroke

The effects of proportional representation and gender orientation of the task on emergent leadership behavior in mixed-gender work groups.

PubMed

Karakowsky, L; Siegel, J P

1999-08-01

Much of the research that has examined the behavioral consequences of membership in mixed-gender work groups suggests that men are more participative and influential in task-related behavior. Drawing from elements of sociological, structural, and psychological perspectives, this study examined the effects of group gender composition and gender orientation of the group's task on patterns of emergent leadership behavior. Participants were assigned to male-dominated, female-dominated, or balanced-gender groups for the purpose of discussing and generating solutions for two business-related cases--each case emphasized either male-oriented or female-oriented expertise. The findings suggest that the proportional representation of men and women in a work group, along with the gender orientation of the group's task, can significantly influence the level of leadership behavior exhibited in group activity.

Converging Work-Talk Patterns in Online Task-Oriented Communities.

PubMed

Xuan, Qi; Devanbu, Premkumar; Filkov, Vladimir

2016-01-01

Much of what we do is accomplished by working collaboratively with others, and a large portion of our lives are spent working and talking; the patterns embodied in the alternation of working and talking can provide much useful insight into task-oriented social behaviors. The available electronic traces of the different kinds of human activities in online communities are an empirical goldmine that can enable the holistic study and understanding of these social systems. Open Source Software (OSS) projects are prototypical examples of collaborative, task-oriented communities, depending on volunteers for high-quality work. Here, we use sequence analysis methods to identify the work-talk patterns of software developers in online communities of Open Source Software projects. We find that software developers prefer to persist in same kinds of activities, i.e., a string of work activities followed by a string of talk activities and so forth, rather than switch them frequently; this tendency strengthens with time, suggesting that developers become more efficient, and can work longer with fewer interruptions. This process is accompanied by the formation of community culture: developers' patterns in the same communities get closer with time while different communities get relatively more different. The emergence of community culture is apparently driven by both "talk" and "work". Finally, we also find that workers with good balance between "work" and "talk" tend to produce just as much work as those that focus strongly on "work"; however, the former appear to be more likely to continue to be active contributors in the communities.

The Acute Effects of Aerobic Exercise on Cognitive Flexibility and Task-Related Heart Rate Variability in Children With ADHD and Healthy Controls.

PubMed

Ludyga, Sebastian; Gerber, Markus; Mücke, Manuel; Brand, Serge; Weber, Peter; Brotzmann, Mark; Pühse, Uwe

2018-02-01

To investigate cognitive flexibility and task-related heart rate variability following moderately intense aerobic exercise and after watching a video in both children with ADHD and healthy controls. Using a cross-over design, participants completed cognitive assessments following exercise and a physically inactive control condition. Behavioral performance was assessed using the Alternate Uses task. Heart rate variability was recorded via electrocardiography during the cognitive task. The statistical analysis revealed that in comparison with the control condition, both groups showed higher cognitive flexibility following aerobic exercise. Moreover, decreased low frequency and high frequency power was observed in the exercise condition. The findings suggest that exercise elicits similar benefits for cognitive flexibility in children with ADHD and healthy controls, partly due to an increase in arousal induced by parasympathetic withdrawal.

Does practicing a wide range of joint angle configurations lead to higher flexibility in a manual obstacle-avoidance target-pointing task?

PubMed Central

Bootsma, Reinoud J.; Schoemaker, Marina M.; Otten, Egbert; Mouton, Leonora J.; Bongers, Raoul M.

2017-01-01

Flexibility in motor actions can be defined as variability in the use of degrees of freedom (e.g., joint angles in the arm) over repetitions while keeping performance (e.g., fingertip position) stabilized. We examined whether flexibility can be increased through enlarging the joint angle range during practice in a manual obstacle-avoidance target-pointing task. To establish differences in flexibility we partitioned the variability in joint angles over repetitions in variability within (GEV) and variability outside the solution space (NGEV). More GEV than NGEV reflects flexibility; when the ratio of the GEV and NGEV is higher, flexibility is higher. The pretest and posttest consisted of 30 repetitions of manual pointing to a target while moving over a 10 cm high obstacle. To enlarge the joint angle range during practice participants performed 600 target-pointing movements while moving over obstacles of different heights (5–9 cm, 11–15 cm). The results indicated that practicing movements over obstacles of different heights led participants to use enlarged range of joint angles compared to the range of joint angles used in movements over the 10 cm obstacle in the pretest. However, for each individual obstacle neither joint angle variance nor flexibility were higher during practice. We also did not find more flexibility after practice. In the posttest, joint angle variance was in fact smaller than before practice, primarily in GEV. The potential influences of learning effects and the task used that could underlie the results obtained are discussed. We conclude that with this specific type of practice in this specific task, enlarging the range of joint angles does not lead to more flexibility. PMID:28700695

Effect of Delay on Search Decisions in a Task-Oriented Reading Environment

ERIC Educational Resources Information Center

Mañá, Amelia; Vidal-Abarca, Eduardo; Salmerón, Ladislao

2017-01-01

The goal of this study was to determine the effect of setting a delay between reading a text and answering comprehension questions on "when"-to-search and "what"-to-search decisions in a task-oriented reading environment. Fifty-five eighth-grade students were randomly divided into two groups. One group read one text, answered…

The relation of locus-of-control orientation and task structure to problem-solving performance of sixth-grade student pairs

NASA Astrophysics Data System (ADS)

Main, June Dewey; Budd Rowe, Mary

This study investigated the relationship of locus-of-control orientations and task structure to the science problem-solving performance of 100 same-sex, sixth-grade student pairs. Pairs performed a four-variable problem-solving task, racing cylinders down a ramp in a series of trials to determine the 3 fastest of 18 different cylinders. The task was completed in one of two treatment conditions: the structured condition with moderate cuing and the unstructured condition with minimal cuing. Pairs completed an after-task assessment, predicting the results of proposed cylinder races, to measure the ability to understand and apply task concepts. Overall conclusions were: (1) There was no relationship between locus-of-control orientation and effectiveness of problem-solving strategy; (2) internality was significantly related to higher accuracy on task solutions and on after-task predictions; (3) there was no significant relationship between task structure and effectiveness of problem-solving strategy; (4) solutions to the task were more accurate in the unstructured task condition; (5) internality related to more accurate solutions in the unstructured task condition.

Rapid instructed task learning: A new window into the human brain’s unique capacity for flexible cognitive control

PubMed Central

Cole, Michael W.; Laurent, Patryk; Stocco, Andrea

2012-01-01

The human ability to flexibly adapt to novel circumstances is extraordinary. Perhaps the most illustrative yet underappreciated form of this cognitive flexibility is rapid instructed task learning (RITL) – the ability to rapidly reconfigure our minds to perform new tasks from instruction. This ability is important for everyday life (e.g., learning to use new technologies), and is used to instruct participants in nearly every study of human cognition. We review the development of RITL as a circumscribed domain of cognitive neuroscience investigation, culminating in recent demonstrations that RITL is implemented via brain circuits centered on lateral prefrontal cortex. We then build on this and other insights to develop an integrative theory of cognitive flexibility and cognitive control, identifying theoretical principles and mechanisms that may make RITL possible in the human brain. Insights gained from this new theoretical account have important implications for further developments and applications of RITL research. PMID:23065743

Vertically Oriented and Interpenetrating CuSe Nanosheet Films with Open Channels for Flexible All-Solid-State Supercapacitors

DOE PAGES

Li, Lingzhi; Gong, Jiangfeng; Liu, Chunyan; ...

2017-03-22

As a p-type multifunctional semiconductor, CuSe nanostructures show great promise in optoelectronic, sensing, and photocatalytic fields. Although great progress has been achieved, controllable synthesis of CuSe nanosheets (NSs) with a desirable spacial orientation and open frameworks remains a challenge, and their use in supercapacitors (SCs) has not been explored. Herein, a highly vertically oriented and interpenetrating CuSe NS film with open channels is deposited on an Au-coated polyethylene terephthalate substrate. Such CuSe NS films exhibit high specific capacitance (209 F g–1) and can be used as a carbon black- and binder-free electrode to construct flexible, symmetric all-solid-state SCs, using polyvinylmore » alcohol–LiCl gel as the solid electrolyte. A device fabricated with such CuSe NS films exhibits high volumetric specific capacitance (30.17 mF cm–3), good cycling stability, excellent flexibility, and desirable mechanical stability. The excellent performance of such devices results from the vertically oriented and interpenetrating configuration of CuSe NS building blocks, which can increase the available surface and facilitate the diffusion of electrolyte ions. Moreover, as a prototype for application, three such solid devices in series can be used to light up a red light-emitting diode.« less

Vertically Oriented and Interpenetrating CuSe Nanosheet Films with Open Channels for Flexible All-Solid-State Supercapacitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Lingzhi; Gong, Jiangfeng; Liu, Chunyan

As a p-type multifunctional semiconductor, CuSe nanostructures show great promise in optoelectronic, sensing, and photocatalytic fields. Although great progress has been achieved, controllable synthesis of CuSe nanosheets (NSs) with a desirable spacial orientation and open frameworks remains a challenge, and their use in supercapacitors (SCs) has not been explored. Herein, a highly vertically oriented and interpenetrating CuSe NS film with open channels is deposited on an Au-coated polyethylene terephthalate substrate. Such CuSe NS films exhibit high specific capacitance (209 F g–1) and can be used as a carbon black- and binder-free electrode to construct flexible, symmetric all-solid-state SCs, using polyvinylmore » alcohol–LiCl gel as the solid electrolyte. A device fabricated with such CuSe NS films exhibits high volumetric specific capacitance (30.17 mF cm–3), good cycling stability, excellent flexibility, and desirable mechanical stability. The excellent performance of such devices results from the vertically oriented and interpenetrating configuration of CuSe NS building blocks, which can increase the available surface and facilitate the diffusion of electrolyte ions. Moreover, as a prototype for application, three such solid devices in series can be used to light up a red light-emitting diode.« less

Use of the Occupational Therapy Task-Oriented Approach to optimize the motor performance of a client with cognitive limitations.

PubMed

Preissner, Katharine

2010-01-01

This case report describes the use of the Occupational Therapy Task-Oriented Approach with a client with occupational performance limitations after a cerebral vascular accident. The Occupational Therapy Task-Oriented Approach is often suggested as a preferred neurorehabilitation intervention to improve occupational performance by optimizing motor behavior. One common critique of this approach, however, is that it may seem inappropriate or have limited application for clients with cognitive deficits. This case report demonstrates how an occupational therapist working in an inpatient rehabilitation setting used the occupational therapy task-oriented evaluation framework and treatment principles described by Mathiowetz (2004) with a person with significant cognitive limitations. This approach was effective in assisting the client in meeting her long-term goals, maximizing her participation in meaningful occupations, and successfully transitioning to home with her daughter.

Flexible Visual Processing in Young Adults with Autism: The Effects of Implicit Learning on a Global-Local Task

ERIC Educational Resources Information Center

Hayward, Dana A.; Shore, David I.; Ristic, Jelena; Kovshoff, Hanna; Iarocci, Grace; Mottron, Laurent; Burack, Jacob A.

2012-01-01

We utilized a hierarchical figures task to determine the default level of perceptual processing and the flexibility of visual processing in a group of high-functioning young adults with autism (n = 12) and a typically developing young adults, matched by chronological age and IQ (n = 12). In one task, participants attended to one level of the…

Task-oriented evaluation of electronic medical records systems: development and validation of a questionnaire for physicians

PubMed Central

2004-01-01

Background Evaluation is a challenging but necessary part of the development cycle of clinical information systems like the electronic medical records (EMR) system. It is believed that such evaluations should include multiple perspectives, be comparative and employ both qualitative and quantitative methods. Self-administered questionnaires are frequently used as a quantitative evaluation method in medical informatics, but very few validated questionnaires address clinical use of EMR systems. Methods We have developed a task-oriented questionnaire for evaluating EMR systems from the clinician's perspective. The key feature of the questionnaire is a list of 24 general clinical tasks. It is applicable to physicians of most specialties and covers essential parts of their information-oriented work. The task list appears in two separate sections, about EMR use and task performance using the EMR, respectively. By combining these sections, the evaluator may estimate the potential impact of the EMR system on health care delivery. The results may also be compared across time, site or vendor. This paper describes the development, performance and validation of the questionnaire. Its performance is shown in two demonstration studies (n = 219 and 80). Its content is validated in an interview study (n = 10), and its reliability is investigated in a test-retest study (n = 37) and a scaling study (n = 31). Results In the interviews, the physicians found the general clinical tasks in the questionnaire relevant and comprehensible. The tasks were interpreted concordant to their definitions. However, the physicians found questions about tasks not explicitly or only partially supported by the EMR systems difficult to answer. The two demonstration studies provided unambiguous results and low percentages of missing responses. In addition, criterion validity was demonstrated for a majority of task-oriented questions. Their test-retest reliability was generally high, and the non

Task-oriented evaluation of electronic medical records systems: development and validation of a questionnaire for physicians.

PubMed

Laerum, Hallvard; Faxvaag, Arild

2004-02-09

Evaluation is a challenging but necessary part of the development cycle of clinical information systems like the electronic medical records (EMR) system. It is believed that such evaluations should include multiple perspectives, be comparative and employ both qualitative and quantitative methods. Self-administered questionnaires are frequently used as a quantitative evaluation method in medical informatics, but very few validated questionnaires address clinical use of EMR systems. We have developed a task-oriented questionnaire for evaluating EMR systems from the clinician's perspective. The key feature of the questionnaire is a list of 24 general clinical tasks. It is applicable to physicians of most specialties and covers essential parts of their information-oriented work. The task list appears in two separate sections, about EMR use and task performance using the EMR, respectively. By combining these sections, the evaluator may estimate the potential impact of the EMR system on health care delivery. The results may also be compared across time, site or vendor. This paper describes the development, performance and validation of the questionnaire. Its performance is shown in two demonstration studies (n = 219 and 80). Its content is validated in an interview study (n = 10), and its reliability is investigated in a test-retest study (n = 37) and a scaling study (n = 31). In the interviews, the physicians found the general clinical tasks in the questionnaire relevant and comprehensible. The tasks were interpreted concordant to their definitions. However, the physicians found questions about tasks not explicitly or only partially supported by the EMR systems difficult to answer. The two demonstration studies provided unambiguous results and low percentages of missing responses. In addition, criterion validity was demonstrated for a majority of task-oriented questions. Their test-retest reliability was generally high, and the non-standard scale was found symmetric and

Effects of Communication Apprehension on Perceptions of Leadership and Intragroup Attraction in Small Task-Oriented Groups.

ERIC Educational Resources Information Center

Hawkins, Katherine; Stewart, Robert A.

1991-01-01

Examines the impact of communication apprehension (CA) on perceptions of leadership and intragroup attraction in small task-oriented groups, using 68 undergraduates working on a class project. Finds high CA students were rated by themselves (and by others) to be lower in emerged leadership and social and task attraction than those with lower CA.…

Mind-wandering and task stimuli: Stimulus-dependent thoughts influence performance on memory tasks and are more often past- versus future-oriented.

PubMed

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.

Directional learning, but no spatial mapping by rats performing a navigational task in an inverted orientation

PubMed Central

Valerio, Stephane; Clark, Benjamin J.; Chan, Jeremy H. M.; Frost, Carlton P.; Harris, Mark J.; Taube, Jeffrey S.

2010-01-01

Previous studies have identified neurons throughout the rat limbic system that fire as a function of the animal's head direction (HD). This HD signal is particularly robust when rats locomote in the horizontal and vertical planes, but is severely attenuated when locomoting upside-down (Calton & Taube, 2005). Given the hypothesis that the HD signal represents an animal's sense of its directional heading, we evaluated whether rats could accurately navigate in an inverted (upside-down) orientation. The task required the animals to find an escape hole while locomoting inverted on a circular platform suspended from the ceiling. In experiment 1, Long-Evans rats were trained to navigate to the escape hole by locomoting from either one or four start points. Interestingly, no animals from the 4-start point group reached criterion, even after 30 days of training. Animals in the 1-start point group reached criterion after about 6 training sessions. In Experiment 2, probe tests revealed that animals navigating from either 1- or 2-start points utilized distal visual landmarks for accurate orientation. However, subsequent probe tests revealed that their performance was markedly attenuated when required to navigate to the escape hole from a novel starting point. This absence of flexibility while navigating upside-down was confirmed in experiment 3 where we show that the rats do not learn to reach a place, but instead learn separate trajectories to the target hole(s). Based on these results we argue that inverted navigation primarily involves a simple directional strategy based on visual landmarks. PMID:20109566

Testing Cross-Cultural Generalizability of the Task and Ego Orientation in Sport Questionnaire across American and Chinese Samples

PubMed Central

Monsma, Eva

2016-01-01

This paper examines the factor structure and measurement invariance of the Task and Ego Orientation in Sport Questionnaire (TEOSQ) across American and Chinese samples. Results based on the mean and covariance structure analyses supported configural invariance, metric invariance and scalar invariance across groups. Latent means analyses revealed that American sample had significantly higher mean scores on task and ego orientations than the Chinese sample. The findings suggest that the TEOSQ is a valid and reliable instrument in assessing achievement motivation across these two diverse populations. PMID:27399869

Enhancing Learning Management Systems Utility for Blind Students: A Task-Oriented, User-Centered, Multi-Method Evaluation Technique

ERIC Educational Resources Information Center

Babu, Rakesh; Singh, Rahul

2013-01-01

This paper presents a novel task-oriented, user-centered, multi-method evaluation (TUME) technique and shows how it is useful in providing a more complete, practical and solution-oriented assessment of the accessibility and usability of Learning Management Systems (LMS) for blind and visually impaired (BVI) students. Novel components of TUME…

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

PubMed

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

2017-09-01

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

Effect of task-oriented activities on hand functions, cognitive functions and self-expression of elderly patients with dementia.

PubMed

Son, Bo-Young; Bang, Yo-Soon; Hwang, Min-Ji; Oh, Eun-Ju

2017-08-01

[Purpose] This study investigates the effects of task-oriented activities on hand function, cognitive function, and self-expression of the elderly with dementia, and then identify the influencing factors on self-expression in sub-factors of dependent variables. [Subjects and Methods] Forty elderly persons were divided into two groups: intervention group (n=20) and control group (n=20). The interventions were applied to the subjects 3 times a week, 50 minutes per each time, for a total of five weeks. We measured the jamar hand dynamometer test for grip strength, the jamar hydraulic pinch gauge test for prehension test, nine-hole pegboard test for coordination test, and Loewenstein Occupational Therapy Cognitive Assessment-Geriatric Population for cognitive function, and self-expression rating scale for self-expression test. [Results] The task-oriented activities promoted hand function, cognitive function (visual perception, spatial perception, visuomotor organization, attention & concentration) and self-expression of the elderly with early dementia, and the factors influencing the self-expression were cognitive function (visual perception) and hand function (coordination). The study showed that the task-oriented program enabled self-expression by improving hand function and cognitive function. [Conclusion] This study suggested that there should be provided the task-oriented program for prevention and treatment of the elderly with early dementia in the clinical settings and it was considered that results have a value as basic data that can be verified relationship of hand function, cognitive function, and self-expression.

Effect of task-oriented activities on hand functions, cognitive functions and self-expression of elderly patients with dementia

PubMed Central

Son, Bo-Young; Bang, Yo-Soon; Hwang, Min-Ji; Oh, Eun-Ju

2017-01-01

[Purpose] This study investigates the effects of task-oriented activities on hand function, cognitive function, and self-expression of the elderly with dementia, and then identify the influencing factors on self-expression in sub-factors of dependent variables. [Subjects and Methods] Forty elderly persons were divided into two groups: intervention group (n=20) and control group (n=20). The interventions were applied to the subjects 3 times a week, 50 minutes per each time, for a total of five weeks. We measured the jamar hand dynamometer test for grip strength, the jamar hydraulic pinch gauge test for prehension test, nine-hole pegboard test for coordination test, and Loewenstein Occupational Therapy Cognitive Assessment-Geriatric Population for cognitive function, and self-expression rating scale for self-expression test. [Results] The task-oriented activities promoted hand function, cognitive function (visual perception, spatial perception, visuomotor organization, attention & concentration) and self-expression of the elderly with early dementia, and the factors influencing the self-expression were cognitive function (visual perception) and hand function (coordination). The study showed that the task-oriented program enabled self-expression by improving hand function and cognitive function. [Conclusion] This study suggested that there should be provided the task-oriented program for prevention and treatment of the elderly with early dementia in the clinical settings and it was considered that results have a value as basic data that can be verified relationship of hand function, cognitive function, and self-expression. PMID:28878462

The paradox of managing a project-oriented matrix: establishing coherence within chaos.

PubMed

Greiner, L E; Schein, V E

1981-01-01

Projects that require the flexible coordination of multidisciplinary teams have tended to adopt a matrix structure to accomplish complex tasks. Yet these project-oriented matrix structures themselves require careful coordination if they are to realize the objectives set for them. The authors identify the basic organizational questions that project-oriented matrix organizations must face. They examine the relationship between responsibility and authority; the tradeoffs between economic efficiency and the technical quality of the work produced; and the sensitive issues of managing individualistic, highly trained professionals while also maintaining group cohesiveness.

Effects of aging and job demands on cognitive flexibility assessed by task switching.

PubMed

Gajewski, Patrick D; Wild-Wall, Nele; Schapkin, Sergei A; Erdmann, Udo; Freude, Gabriele; Falkenstein, Michael

2010-10-01

In a cross-sectional, electrophysiological study 91 workers of a big car factory performed a series of switch tasks to assess their cognitive control functions. Four groups of workers participated in the study: 23 young and 23 middle aged assembly line employees and 22 young and 23 middle aged employees with flexible job demands like service and maintenance. Participants performed three digit categorisation tasks. In addition to single task blocks, a cue-based (externally guided) and a memory-based (internally guided) task switch block was administered. Compared to young participants, older ones showed the typical RT-decline. No differences between younger and older participants regarding the local switch costs could be detected despite the source of the current task information. In contrast, whereas the groups did not differ in mixing costs in the cued condition, clear performance decrements in the memory-based mixing block were observed in the group of older employees with repetitive work demands. These findings were corroborated by a number of electrophysiological results showing a reduced CNV suggesting an impairment of task specific preparation, an attenuated P3b suggesting reduced working memory capacity and a decreased Ne suggesting deficits in error monitoring in older participants with repetitive job demands. The results are compatible with the assumption that long lasting, unchallenging job demands may induce several neurocognitive impairments which are already evident in the early fifties. Longitudinal studies are needed to confirm this assumption. Copyright © 2010 Elsevier B.V. All rights reserved.

Canonical Correlational Models of Students' Perceptions of Assessment Tasks, Motivational Orientations, and Learning Strategies

ERIC Educational Resources Information Center

Alkharusi, Hussain

2013-01-01

The present study aims at deriving correlational models of students' perceptions of assessment tasks, motivational orientations, and learning strategies using canonical analyses. Data were collected from 198 Omani tenth grade students. Results showed that high degrees of authenticity and transparency in assessment were associated with positive…

Task-Oriented Gaming for Transfer to Prosthesis Use.

PubMed

van Dijk, Ludger; van der Sluis, Corry K; van Dijk, Hylke W; Bongers, Raoul M

2016-12-01

The aim of this study is to establish the effect of task-oriented video gaming on using a myoelectric prosthesis in a basic activity of daily life (ADL). Forty-one able-bodied right-handed participants were randomly assigned to one of four groups. In three of these groups the participants trained to control a video game using the myosignals of the flexors and extensors of the wrist: in the Adaptive Catching group participants needed to catch falling objects by opening and closing a grabber and received ADL-relevant feedback during performance. The Free Catching group used the same game, but without augmented feedback. The Interceptive Catching group trained a game where the goal was to intercept a falling object by moving a grabber to the left and right. They received no additional feedback. The control group played a regular Mario computer game. All groups trained 20 minutes a day for four consecutive days. Two tests were conducted before and after training: one level of the training game was performed, and participants grasped objects with a prosthesis simulator. Results showed all groups improved their game performance over controls. In the prosthesis-simulator task, after training the Adaptive Catching group outperformed the other groups in their ability to adjust the hand aperture to the size of the objects and the degree of compression of compressible objects. This study is the first to demonstrate transfer effects from a serious game to a myoelectric prosthesis task. The specificity of the learning effects suggests that research into serious gaming will benefit from placing ADL-specific constraints on game development.

Flexible, task-dependent use of sensory feedback to control hand movements

PubMed Central

Knill, David C.; Bondada, Amulya; Chhabra, Manu

2011-01-01

We tested whether changing accuracy demands for simple pointing movements leads humans to adjust the feedback control laws that map sensory signals from the moving hand to motor commands. Subjects made repeated pointing movements in a virtual environment to touch a button whose shape varied randomly from trial-to-trial – between squares, rectangles oriented perpendicular to the movement path and rectangles oriented parallel to the movement path. Subjects performed the task on a horizontal table, but saw the target configuration and a virtual rendering of their pointing finger through a mirror mounted between a monitor and the table. On a one-third of trials, the position of the virtual finger was perturbed by ±1 cm either in the movement direction or perpendicular to the movement direction when the finger passed behind an occluder. Subjects corrected quickly for the perturbations despite not consciously noticing them; however, they corrected almost twice as much for perturbations aligned with the narrow dimension of a target than for perturbations aligned with the long dimension. These changes in apparent feedback gain appeared in the kinematic trajectories soon after the time of the perturbations, indicating that they reflect differences in the feedback control law used throughout the duration of movements. The results indicate that the brain adjusts its feedback control law for individual movements “on-demand” to fit task demands. Simulations of optimal control laws for a two-joint arm show that accuracy demands alone, coupled with signal dependent noise lead to qualitatively the same behavior. PMID:21273407

Hand and Grasp Selection in a Preferential Reaching Task: The Effects of Object Location, Orientation, and Task Intention.

PubMed

Scharoun, Sara M; Scanlan, Kelly A; Bryden, Pamela J

2016-01-01

As numerous movement options are available in reaching and grasping, of particular interest are what factors influence an individual's choice of action. In the current study a preferential reaching task was used to assess the propensity for right handers to select their preferred hand and grasp a coffee mug by the handle in both independent and joint action object manipulation contexts. Mug location (right-space, midline, and left-space) and handle orientation (toward, away, to left, and to right of the participant) varied in four tasks that differed as a function of intention: (1) pick-up (unimanual, independent); (2) pick-up and pour (bimanual, independent); (3) pick-up and pass (unimanual, joint action); and (4) pick-up, pour and pass (bimanual, joint action). In line with previous reports, a right-hand preference for unimanual tasks was observed. Furthermore, extending existing literature to a preferential reaching task, role differentiation between the hands in bimanual tasks (i.e., preferred hand mobilizing, non-preferred hand stabilizing) was displayed. Finally, right-hand selection was greatest in right space, albeit lower in bimanual tasks compared to what is typically reported in unimanual tasks. Findings are attributed to the desire to maximize biomechanical efficiency in reaching. Grasp postures were also observed to reflect consideration of efficiency. More specifically, within independent object manipulation (pick-up; pick-up and pour) participants only grasped the mug by the handle when it afforded a comfortable posture. Furthermore, in joint action (pick-up and pass; pick-up, pour and pass), the confederate was only offered the handle if the intended action of the confederate was similar or required less effort than that of the participant. Together, findings from the current study add to our knowledge of hand and grasp selection in unimanual and bimanual object manipulation, within the context of both independent and joint action tasks.

Object oriented development of engineering software using CLIPS

NASA Technical Reports Server (NTRS)

Yoon, C. John

1991-01-01

Engineering applications involve numeric complexity and manipulations of a large amount of data. Traditionally, numeric computation has been the concern in developing an engineering software. As engineering application software became larger and more complex, management of resources such as data, rather than the numeric complexity, has become the major software design problem. Object oriented design and implementation methodologies can improve the reliability, flexibility, and maintainability of the resulting software; however, some tasks are better solved with the traditional procedural paradigm. The C Language Integrated Production System (CLIPS), with deffunction and defgeneric constructs, supports the procedural paradigm. The natural blending of object oriented and procedural paradigms has been cited as the reason for the popularity of the C++ language. The CLIPS Object Oriented Language's (COOL) object oriented features are more versatile than C++'s. A software design methodology based on object oriented and procedural approaches appropriate for engineering software, and to be implemented in CLIPS was outlined. A method for sensor placement for Space Station Freedom is being implemented in COOL as a sample problem.

Orienting in virtual environments: How are surface features and environmental geometry weighted in an orientation task?

PubMed

Kelly, Debbie M; Bischof, Walter F

2008-10-01

We investigated how human adults orient in enclosed virtual environments, when discrete landmark information is not available and participants have to rely on geometric and featural information on the environmental surfaces. In contrast to earlier studies, where, for women, the featural information from discrete landmarks overshadowed the encoding of the geometric information, Experiment 1 showed that when featural information is conjoined with the environmental surfaces, men and women encoded both types of information. Experiment 2 showed that, although both types of information are encoded, performance in locating a goal position is better if it is close to a geometrically or featurally distinct location. Furthermore, although features are relied upon more strongly than geometry, initial experience with an environment influences the relative weighting of featural and geometric cues. Taken together, these results show that human adults use a flexible strategy for encoding spatial information.

The Challenge of Induction! Introducing Engineering Students to Higher Education: A Task-Oriented Approach.

ERIC Educational Resources Information Center

Edward, Norrie; Middleton, June

2002-01-01

First-year engineering students at Robert Gordon University (Scotland) were presented with a task-oriented induction program. Students were divided into groups and assigned a facilitator, later personal tutor, to whom they could refer. Student reaction to the experience was very favorable. Effect on progression rates is yet to be determined. (AEF)

Cognitive deficits in obese persons with and without binge eating disorder. Investigation using a mental flexibility task.

PubMed

Mobbs, Olivia; Iglesias, Katia; Golay, Alain; Van der Linden, Martial

2011-08-01

Studies suggest that cognitive deficits and attentional biases play a role in the development and maintenance of obesity and eating disorders. In this study, we simultaneously examine attentional biases, as well as inhibitory control and mental flexibility, which are keys to controlling unwanted behaviors and thoughts in obese patients with and without binge eating disorder. 16 obese patients with binge eating disorder and 16 patients without binge eating disorder were compared with 16 normal-weight controls on a "food/body-mental flexibility task", which allows the investigation of inhibitory control, mental flexibility and attention for stimuli related to the body and food. All obese patients made significantly more errors (i.e., pressing a key when a distracter displayed) and more omissions (i.e., not pressing a key when a target displayed) than controls in both food and body sections of the task. Obese participants with binge eating disorder made significantly more errors and omissions than those without binge eating disorder. No difference between groups was found concerning mental flexibility and cognitive biases for food- and body-related targets. These results suggest that obese patients have a general inhibition problem and difficulty focusing attention, which do not depend on the types of stimuli processed. The results also suggest that these cognitive deficits are more severe in obese patients with binge eating disorder, which indicates that there is a continuum of increasing inhibition and cognitive problems with increasingly disordered eating. These cognitive deficits may contribute to problematic eating behaviors. Copyright © 2011 Elsevier Ltd. All rights reserved.

A psychotherapeutic approach to task-oriented groups of severely ill patients.

PubMed Central

Wilson, W. H.; Diamond, R. J.; Factor, R. M.

1985-01-01

This paper presents a conceptual approach for leading various types of groups of chronically mentally ill patients. Although these groups may have a concrete, task-oriented purpose, with skillful leadership they also function as psychotherapy groups. The developmental deficits in ego functions, object relations, and social skills that severely impair such groups can be compensated by non-interpretative actions of the therapists. The group leader must actively work to provide for the structure, stability, and safety of the group when group members are unable to provide these for themselves. PMID:4049917

Task-oriented lossy compression of magnetic resonance images

NASA Astrophysics Data System (ADS)

Anderson, Mark C.; Atkins, M. Stella; Vaisey, Jacques

1996-04-01

A new task-oriented image quality metric is used to quantify the effects of distortion introduced into magnetic resonance images by lossy compression. This metric measures the similarity between a radiologist's manual segmentation of pathological features in the original images and the automated segmentations performed on the original and compressed images. The images are compressed using a general wavelet-based lossy image compression technique, embedded zerotree coding, and segmented using a three-dimensional stochastic model-based tissue segmentation algorithm. The performance of the compression system is then enhanced by compressing different regions of the image volume at different bit rates, guided by prior knowledge about the location of important anatomical regions in the image. Application of the new system to magnetic resonance images is shown to produce compression results superior to the conventional methods, both subjectively and with respect to the segmentation similarity metric.

Test-retest stability of the Task and Ego Orientation Questionnaire.

PubMed

Lane, Andrew M; Nevill, Alan M; Bowes, Neal; Fox, Kenneth R

2005-09-01

Establishing stability, defined as observing minimal measurement error in a test-retest assessment, is vital to validating psychometric tools. Correlational methods, such as Pearson product-moment, intraclass, and kappa are tests of association or consistency, whereas stability or reproducibility (regarded here as synonymous) assesses the agreement between test-retest scores. Indexes of reproducibility using the Task and Ego Orientation in Sport Questionnaire (TEOSQ; Duda & Nicholls, 1992) were investigated using correlational (Pearson product-moment, intraclass, and kappa) methods, repeated measures multivariate analysis of variance, and calculating the proportion of agreement within a referent value of +/-1 as suggested by Nevill, Lane, Kilgour, Bowes, and Whyte (2001). Two hundred thirteen soccer players completed the TEOSQ on two occasions, 1 week apart. Correlation analyses indicated a stronger test-retest correlation for the Ego subscale than the Task subscale. Multivariate analysis of variance indicated stability for ego items but with significant increases in four task items. The proportion of test-retest agreement scores indicated that all ego items reported relatively poor stability statistics with test-retest scores within a range of +/-1, ranging from 82.7-86.9%. By contrast, all task items showed test-retest difference scores ranging from 92.5-99%, although further analysis indicated that four task subscale items increased significantly. Findings illustrated that correlational methods (Pearson product-moment, intraclass, and kappa) are influenced by the range in scores, and calculating the proportion of agreement of test-retest differences with a referent value of +/-1 could provide additional insight into the stability of the questionnaire. It is suggested that the item-by-item proportion of agreement method proposed by Nevill et al. (2001) should be used to supplement existing methods and could be especially helpful in identifying rogue items in the

Effects of Task-oriented Approach on Affected Arm Function in Children with Spastic Hemiplegia Due to Cerebral Palsy.

PubMed

Song, Chiang-Soon

2014-06-01

[Purpose] The purpose of the present study was to examine the effects of task-oriented approach on motor function of the affected arm in children with spastic hemiplegia due to cerebral palsy. [Subjects] Twelve children were recruited by convenience sampling from 2 local rehabilitation centers. The present study utilized a one-group pretest-posttest design. All of children received task-oriented training for 6 weeks (40 min/day, 5 days/week) and also underwent regular occupational therapy. Three clinical tests, Box and Block Test (BBT), Manual Ability Measure (MAM-16), and Wee Functional Independence Measure (WeeFIM) were performed 1 day before and after training to evaluate the effects of the training. [Results] Compared with the pretest scores, there was a significant increase in the BBT, MAM-16, and WeeFIM scores of the children after the 6-week practice period. [Conclusion] The results of this study suggest that a task-oriented approach to treatment of the affected arm improves functional activities, such as manual dexterity and fine motor performance, as well as basic daily activities of patients with spastic hemiplegia due to cerebral palsy.

Orienting task effects on EDR and free recall in three age groups.

PubMed

Zelinski, E M; Walsh, D A; Thompson, L W

1978-03-01

The present investigation was designed to examine the effects of orienting task-controlled processing on electrodermal response and free recall at two delay intervals for 94 young, 49 young-old (age 55 to 70), and 61 old-old (age 71 to 85) individuals. Subjects were presented with a list of 25 words and performed one of the following tasks: semantic, nonsemantic, or passive listening, presented in an incidental memory paradigm, or intentional memorization. Recall was obtained 2 min or 48 hours after list presentation. At the 2-min delay, the pattern of recall across tasks for the young-old and old-old subjects was similar to that of college students. Overall, the old-old recalled fewer words than the young and young-old, while the young-old recalled as many words as the young. After 48 hours, the task-related recall pattern was observed only in the young group. The skin conductance data indicated that task effects were similar across the three age groups and that response magnitude was lower in the old-old than the two younger groups. No differences in skin conductance were found between the young and young-old. Age differences in memory processing suggest that difficulties in delayed retrieval of semantically encoded words may increase during late adult years. Differences in electrodermal responses in the old-old compared to the young and young-old suggest that the range of autonomic responsivitiy to task demands may become restricted in advanced age.

Temporal motifs reveal collaboration patterns in online task-oriented networks

NASA Astrophysics Data System (ADS)

Xuan, Qi; Fang, Huiting; Fu, Chenbo; Filkov, Vladimir

2015-05-01

Real networks feature layers of interactions and complexity. In them, different types of nodes can interact with each other via a variety of events. Examples of this complexity are task-oriented social networks (TOSNs), where teams of people share tasks towards creating a quality artifact, such as academic research papers or software development in commercial or open source environments. Accomplishing those tasks involves both work, e.g., writing the papers or code, and communication, to discuss and coordinate. Taking into account the different types of activities and how they alternate over time can result in much more precise understanding of the TOSNs behaviors and outcomes. That calls for modeling techniques that can accommodate both node and link heterogeneity as well as temporal change. In this paper, we report on methodology for finding temporal motifs in TOSNs, limited to a system of two people and an artifact. We apply the methods to publicly available data of TOSNs from 31 Open Source Software projects. We find that these temporal motifs are enriched in the observed data. When applied to software development outcome, temporal motifs reveal a distinct dependency between collaboration and communication in the code writing process. Moreover, we show that models based on temporal motifs can be used to more precisely relate both individual developer centrality and team cohesion to programmer productivity than models based on aggregated TOSNs.

Temporal motifs reveal collaboration patterns in online task-oriented networks.

PubMed

Xuan, Qi; Fang, Huiting; Fu, Chenbo; Filkov, Vladimir

2015-05-01

Real networks feature layers of interactions and complexity. In them, different types of nodes can interact with each other via a variety of events. Examples of this complexity are task-oriented social networks (TOSNs), where teams of people share tasks towards creating a quality artifact, such as academic research papers or software development in commercial or open source environments. Accomplishing those tasks involves both work, e.g., writing the papers or code, and communication, to discuss and coordinate. Taking into account the different types of activities and how they alternate over time can result in much more precise understanding of the TOSNs behaviors and outcomes. That calls for modeling techniques that can accommodate both node and link heterogeneity as well as temporal change. In this paper, we report on methodology for finding temporal motifs in TOSNs, limited to a system of two people and an artifact. We apply the methods to publicly available data of TOSNs from 31 Open Source Software projects. We find that these temporal motifs are enriched in the observed data. When applied to software development outcome, temporal motifs reveal a distinct dependency between collaboration and communication in the code writing process. Moreover, we show that models based on temporal motifs can be used to more precisely relate both individual developer centrality and team cohesion to programmer productivity than models based on aggregated TOSNs.

Motor planning flexibly optimizes performance under uncertainty about task goals.

PubMed

Wong, Aaron L; Haith, Adrian M

2017-03-03

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

Life cycle assessment of flexibly fed biogas processes for an improved demand-oriented biogas supply.

PubMed

Ertem, Funda Cansu; Martínez-Blanco, Julia; Finkbeiner, Matthias; Neubauer, Peter; Junne, Stefan

2016-11-01

This paper analyses concepts to facilitate a demand oriented biogas supply at an agricultural biogas plant of a capacity of 500kWhel, operated with the co-digestion of maize, grass, rye silage and chicken manure. In contrast to previous studies, environmental impacts of flexible and the traditional baseload operation are compared. Life Cycle Assessment (LCA) was performed to detect the environmental impacts of: (i) variety of feedstock co-digestion scenarios by substitution of maize and (ii) loading rate scenarios with a focus on flexible feedstock utilization. Demand-driven biogas production is critical for an overall balanced power supply to the electrical grid. It results in lower amounts of emissions; feedstock loading rate scenarios resulted in 48%, 20%, 11% lower global warming (GWP), acidification (AP) and eutrophication potentials, and a 16% higher cumulative energy demand. Substitution of maize with biogenic-waste regarding to feedstock substitution scenarios could create 10% lower GWP and AP. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Role of Motivating Tasks and Personal Goal Orientations in Students' Coping Strategies in Science

ERIC Educational Resources Information Center

Subasi, Münevver; Tas, Yasemin

2016-01-01

This study aims to investigate coping strategies of middle school students in science classes in relation to students' goal orientations and motivating tasks conducted in the classroom environment. The study was conducted in spring semester of 2015-2016 academic year. Sample of the study consists of 316 middle school students receiving education…

Sustained selective attention predicts flexible switching in preschoolers

PubMed Central

Benitez, Viridiana L.; Vales, Catarina; Hanania, Rima; Smith, Linda B.

2016-01-01

Stability and flexibility are fundamental to an intelligent cognitive system. Here, we examine the relationship between stability in selective attention and explicit control of flexible attention. Preschoolers were tested on the Dimension-Preference (DP) task, a task that measures the stability of selective attention to an implicitly primed dimension, and the Dimension-Change Card Sort Task (DCCS), a task that measures flexible attention switching between dimensions. Children who successfully switched on the DCCS task were more likely than those who perseverated to sustain attention to the primed dimension on the DP task across trials. We propose that perseverators have less stable attention and distribute their attention between dimensions, while switchers can successfully stabilize attention to individual dimensions and thus show more enduring priming effects. Flexible attention may emerge, in part, from implicit processes that stabilize attention even in tasks not requiring switching. PMID:28024178

Relationships between child-reported activity level and task orientation and parental attention-deficit/hyperactivity disorder symptom ratings.

PubMed

Bell, Lindsay; Kellison, Ida; Garvan, Cynthia W; Bussing, Regina

2010-04-01

This study examines whether elementary school-aged children can report behaviors relevant to assessing symptoms of attention-deficit/hyperactivity disorder (ADHD). Interviews were conducted with 120 children aged 6 to 12 years and their parents across 3 waves as part of a longitudinal cohort study of ADHD detection and service use. Child self-reports obtained through the Dimensions of Temperament Scale-Revised-Child (DOTS-R-C) were correlated with parent-reported ADHD symptoms, which were assessed through DSM-IV-based instrument ratings obtained concurrently and 5 years later. The Dimensions of Temperament Scale-Revised-Child subscales Activity Level and Task Orientation demonstrate adequate internal consistency after eliminating items requiring reverse scoring. Children's self-reports of Task Orientation Problems correlate with their parents' concurrent reports of inattention, r(117) = .23, p < .05, and with parents' Wave 3 reports of inattention, r(118) = .25, p < .01 as well as hyperactivity, r(118) = .25, p < .01. Children's self-reports of Activity Level correlate with their parents' concurrent reports of hyperactivity, r(117) = .21, p < .05, as well as Wave 3 reports of hyperactivity/impulsivity, r(118) = .37, p < .001 and inattention, r(118) = .23, p < .05. Findings suggest that children may be capable of producing meaningful self-reports of Activity Level and Task Orientation. We propose that the development of child-friendly self-report instruments targeting ADHD symptoms is merited to facilitate the collection of child input during ADHD assessments.

Sex differences in young children's use of tools in a problem-solving task : The role of object-oriented play.

PubMed

Gredlein, Jeffrey M; Bjorklund, David F

2005-06-01

Three-year-old children were observed in two free-play sessions and participated in a toy-retrieval task, in which only one of six tools could be used to retrieve an out-of-reach toy. Boys engaged in more object-oriented play than girls and were more likely to use tools to retrieve the toy during the baseline tool-use task. All children who did not retrieve the toy during the baseline trials did so after being given a hint, and performance on a transfer-of-training tool-use task approached ceiling levels. This suggests that the sex difference in tool use observed during the baseline phase does not reflect a difference in competency, but rather a sex difference in motivation to interact with objects. Amount of time boys, but not girls, spent in object-oriented play during the free-play sessions predicted performance on the tool-use task. The findings are interpreted in terms of evolutionary theory, consistent with the idea that boys' and girls' play styles evolved to prepare them for adult life in traditional environments.

Measuring implicit gender-role orientation: the gender initial preference task.

PubMed

Stieger, Stefan; Burger, Christoph; Schiller, Franziska R; Schulze, Esther K; Voracek, Martin

2014-01-01

Individuals prefer their name letters over nonname letters, which is known as the name-letter effect (NLE). This research aimed to examine a possible NLE for gender-role orientation (GRO) by rating letters for their gender-typicality in an initial preference task (Gender-IPT). Indeed, a clear NLE appeared: Men rated their initials as more male-typical, whereas women rated them as more female-typical. The Gender-IPT showed good convergent validity with other direct and indirect (Gender Implicit Association Test) measures of GRO as well as predictive validity with sensation seeking and gender-typical everyday life behaviors. The Gender-IPT seems to be a useful and practical indirect measure to assess GRO in a short, convenient, and computer-independent way, complementing other indirect measures of GRO.

Foreign Language Learning Using E-Mail in a Task-Oriented Perspective: Interuniversity Experiments in Communication and Collaboration.

ERIC Educational Resources Information Center

Barson, John; And Others

1993-01-01

Describes collaborations of college French classes using electronic mail. Suggests that this type of task-oriented learning through distance-communication is applicable at many different course levels and has considerable merit as an approach to teaching and learning. (PR)

Task-Oriented Training with Computer Games for People with Rheumatoid Arthritis or Hand Osteoarthritis: A Feasibility Randomized Controlled Trial.

PubMed

Srikesavan, Cynthia Swarnalatha; Shay, Barbara; Szturm, Tony

2016-09-13

To examine the feasibility of a clinical trial on a novel, home-based task-oriented training with conventional hand exercises in people with rheumatoid arthritis or hand osteoarthritis. To explore the experiences of participants who completed their respective home exercise programmes. Thirty volunteer participants aged between 30 and 60 years and diagnosed with rheumatoid arthritis or hand osteoarthritis were proposed for a single-center, assessor-blinded, randomized controlled trial ( ClinicalTrials.gov : NCT01635582). Participants received task-oriented training with interactive computer games and objects of daily life or finger mobility and strengthening exercises. Both programmes were home based and were done four sessions per week with 20 minutes each session for 6 weeks. Major feasibility outcomes were number of volunteers screened, randomized, and retained; completion of blinded assessments, exercise training, and home exercise sessions; equipment and data management; and clinical outcomes of hand function. Reaching the recruitment target in 18 months and achieving exercise compliance >80% were set as success criteria. Concurrent with the trial, focus group interviews explored experiences of those participants who completed their respective programmes. After trial initiation, revisions in inclusion criteria were required to promote recruitment. A total of 17 participants were randomized and 15 were retained. Completion of assessments, exercise training, and home exercise sessions; equipment and data collection and management demonstrated excellent feasibility. Both groups improved in hand function outcomes and exercise compliance was above 85%. Participants perceived both programmes as appropriate and acceptable. Participants who completed task-oriented training also agreed that playing different computer games was enjoyable, engaging, and motivating. Findings demonstrate initial evidence on recruitment, feasibility of trial procedures, and acceptability of

Object-oriented design for accelerator control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stok, P.D.V. van der; Berk, F. van den; Deckers, R.

1994-02-01

An object-oriented design for the distributed computer control system of the accelerator ring EUTERPE is presented. Because of the experimental nature of the ring, flexibility is of the utmost importance. The object-oriented principles have contributed considerably to the flexibility of the design incorporating multiple views, multi-level access and distributed surveillance.

Individual variation in foraging behavior reveals a trade-off between flexibility and performance of a top predator

PubMed Central

McGhee, Katie E.; Roche, Daniel P.; Bell, Alison M.

2017-01-01

There is increasing evidence that behavioral flexibility is associated with the ability to adaptively respond to environmental change. Flexibility can be advantageous in some contexts such as exploiting novel resources, but it may come at a cost of accuracy or performance in ecologically relevant tasks, such as foraging. Such trade-offs may, in part, explain why individuals within a species are not equally flexible. Here, we conducted a reversal learning task and predation experiment on a top fish predator, the Northern pike (Esox lucius), to examine individual variation in flexibility and test the hypothesis that an individual’s behavioral flexibility is negatively related with its foraging performance. Pikes were trained to receive a food reward from either a red or blue cup and then the color of the rewarded cup was reversed. We found that pike improved over time in how quickly they oriented to the rewarded cup, but there was a bias toward the color red. Moreover, there was substantial variation among individuals in their ability to overcome this red bias and switch from an unrewarded red cup to the rewarded blue cup, which we interpret as consistent variation among individuals in behavioral flexibility. Furthermore, individual differences in behavioral flexibility were negatively associated with foraging performance on ecologically relevant stickleback prey. Our data indicate that individuals cannot be both behaviorally flexible and efficient predators, suggesting a trade-off between these two traits. PMID:29046598

Motivation and Performance within a Collaborative Computer-Based Modeling Task: Relations between Students' Achievement Goal Orientation, Self-Efficacy, Cognitive Processing, and Achievement

ERIC Educational Resources Information Center

Sins, Patrick H. M.; van Joolingen, Wouter R.; Savelsbergh, Elwin R.; van Hout-Wolters, Bernadette

2008-01-01

Purpose of the present study was to test a conceptual model of relations among achievement goal orientation, self-efficacy, cognitive processing, and achievement of students working within a particular collaborative task context. The task involved a collaborative computer-based modeling task. In order to test the model, group measures of…

Task-Based Teaching of English-Chinese Translation under "Caliber-Oriented Education to Success" Based on Web

NASA Astrophysics Data System (ADS)

Duan, Zhongyan

This paper, under 3-using principle in the philosophy of caliber-oriented education to success (CETS), makes a tentative qualitative study on the application of task-based approach in the teaching of English-Chinese translation based on the web. Translation teaching is characterized by its practicality. Therefore, the task-based approach can be employed to guide the web-based content collection and the process of English translation teaching. In this way, the prospect for enhancing student's translation ability is quite encouraging, which has been verified by one year's teaching.

Flow theory – goal orientation theory: positive experience is related to athlete’s goal orientation

PubMed Central

Stavrou, Nektarios A. M.; Psychountaki, Maria; Georgiadis, Emmanouil; Karteroliotis, Konstantinos; Zervas, Yannis

2015-01-01

The main purpose of this study was to examine the relationship between flow experience and goal orientation theory, as well as, the differences in flow experience based on the orthogonal model of goal orientation theory. Two hundred and seventy eight athletes completed the Task and Ego Orientation Sport Questionnaire based on how they usually feel. The challenge and skills ratings were completed 1 h before the competition, based on how they felt at the exact time of answering. In the following, the Flow State Scale-2 was completed up to 30 min after the competition they just participated, along with the challenge-skill ratings, based on how athletes felt during the competition. The results indicated that the athletes’ task orientation may be an important factor for attaining flow in competitive sport, feeling more skillful and estimating the upcoming competition as challenging, while low ego and low task oriented athletes lack these elements, which are important for them to get into flow. Additionally, not the level of task and ego orientation per se, but the balance between athletes’ goal orientation preferences seems important for the formation of flow experience, indicating that high task – high ego and high task – low ego athletes are experiencing the most positive mental state. PMID:26500577

A novel task-oriented optimal design for P300-based brain-computer interfaces.

PubMed

Zhou, Zongtan; Yin, Erwei; Liu, Yang; Jiang, Jun; Hu, Dewen

2014-10-01

Objective. The number of items of a P300-based brain-computer interface (BCI) should be adjustable in accordance with the requirements of the specific tasks. To address this issue, we propose a novel task-oriented optimal approach aimed at increasing the performance of general P300 BCIs with different numbers of items. Approach. First, we proposed a stimulus presentation with variable dimensions (VD) paradigm as a generalization of the conventional single-character (SC) and row-column (RC) stimulus paradigms. Furthermore, an embedding design approach was employed for any given number of items. Finally, based on the score-P model of each subject, the VD flash pattern was selected by a linear interpolation approach for a certain task. Main results. The results indicate that the optimal BCI design consistently outperforms the conventional approaches, i.e., the SC and RC paradigms. Specifically, there is significant improvement in the practical information transfer rate for a large number of items. Significance. The results suggest that the proposed optimal approach would provide useful guidance in the practical design of general P300-based BCIs.

A novel task-oriented optimal design for P300-based brain-computer interfaces

NASA Astrophysics Data System (ADS)

Zhou, Zongtan; Yin, Erwei; Liu, Yang; Jiang, Jun; Hu, Dewen

2014-10-01

Objective. The number of items of a P300-based brain-computer interface (BCI) should be adjustable in accordance with the requirements of the specific tasks. To address this issue, we propose a novel task-oriented optimal approach aimed at increasing the performance of general P300 BCIs with different numbers of items. Approach. First, we proposed a stimulus presentation with variable dimensions (VD) paradigm as a generalization of the conventional single-character (SC) and row-column (RC) stimulus paradigms. Furthermore, an embedding design approach was employed for any given number of items. Finally, based on the score-P model of each subject, the VD flash pattern was selected by a linear interpolation approach for a certain task. Main results. The results indicate that the optimal BCI design consistently outperforms the conventional approaches, i.e., the SC and RC paradigms. Specifically, there is significant improvement in the practical information transfer rate for a large number of items. Significance. The results suggest that the proposed optimal approach would provide useful guidance in the practical design of general P300-based BCIs.

Effect of task-oriented training and high-variability practice on gross motor performance and activities of daily living in children with spastic diplegia.

PubMed

Kwon, Hae-Yeon; Ahn, So-Yoon

2016-10-01

[Purpose] This study investigates how a task-oriented training and high-variability practice program can affect the gross motor performance and activities of daily living for children with spastic diplegia and provides an effective and reliable clinical database for future improvement of motor performances skills. [Subjects and Methods] This study randomly assigned seven children with spastic diplegia to each intervention group including that of a control group, task-oriented training group, and a high-variability practice group. The control group only received neurodevelopmental treatment for 40 minutes, while the other two intervention groups additionally implemented a task-oriented training and high-variability practice program for 8 weeks (twice a week, 60 min per session). To compare intra and inter-relationships of the three intervention groups, this study measured gross motor performance measure (GMPM) and functional independence measure for children (WeeFIM) before and after 8 weeks of training. [Results] There were statistically significant differences in the amount of change before and after the training among the three intervention groups for the gross motor performance measure and functional independence measure. [Conclusion] Applying high-variability practice in a task-oriented training course may be considered an efficient intervention method to improve motor performance skills that can tune to movement necessary for daily livelihood through motor experience and learning of new skills as well as change of tasks learned in a complex environment or similar situations to high-variability practice.

Effects of peripheral sensory nerve stimulation plus task-oriented training on upper extremity function in patients with subacute stroke: a pilot randomized crossover trial.

PubMed

Ikuno, Koki; Kawaguchi, Saori; Kitabeppu, Shinsuke; Kitaura, Masaki; Tokuhisa, Kentaro; Morimoto, Shigeru; Matsuo, Atsushi; Shomoto, Koji

2012-11-01

To investigate the feasibility of peripheral sensory nerve stimulation combined with task-oriented training in patients with stroke during inpatient rehabilitation. A pilot randomized crossover trial. Two rehabilitation hospitals. Twenty-two patients with subacute stroke. Participants were randomly assigned to two groups and underwent two weeks of training in addition to conventional inpatient rehabilitation. The immediate group underwent peripheral sensory nerve stimulation combined with task-oriented training in the first week, followed by another week with task-oriented training alone. The delayed group underwent the same training in reverse order. Outcome measures were the level of fatigue and Wolf Motor Function Test. Patients were assessed at baseline, one and two weeks. All participants completed the study with no adverse events. There was no significant difference in level of fatigue between each treatment. From baseline to one week, the immediate group showed larger improvements than the delayed groups in the Wolf Motor Function Test (decrease in mean time (± SD) from 41.9 ± 16.2 seconds to 30.6 ± 11.4 seconds versus from 46.8 ± 19.4 seconds to 42.9 ± 14.7 seconds, respectively) but the difference did not reach significance after Bonferroni correction (P = 0.041). Within-group comparison showed significant improvements in the Wolf Motor Function Test mean time after the peripheral sensory nerve stimulation combined with task-oriented training periods in each group (P < 0.01). Peripheral sensory nerve stimulation is feasible in clinical settings and may enhance the effects of task-oriented training in patients with subacute stroke.

Visuo-spatial orienting during active exploratory behavior: Processing of task-related and stimulus-related signals.

PubMed

Macaluso, Emiliano; Ogawa, Akitoshi

2018-05-01

Functional imaging studies have associated dorsal and ventral fronto-parietal regions with the control of visuo-spatial attention. Previous studies demonstrated that the activity of both the dorsal and the ventral attention systems can be modulated by many different factors, related both to the stimuli and the task. However, the vast majority of this work utilized stereotyped paradigms with simple and repeated stimuli. This is at odd with any real life situation that instead involve complex combinations of different types of co-occurring signals, thus raising the question of the ecological significance of the previous findings. Here we investigated how the brain responds to task-related and stimulus-related signals using an innovative approach that involved active exploration of a virtual environment. This enabled us to study visuo-spatial orienting in conditions entailing a dynamic and coherent flow of visual signals, to some extent analogous to real life situations. The environment comprised colored/textured spheres and cubes, which allowed us to implement a standard feature-conjunction search task (task-related signals), and included one physically salient object that served to track the processing of stimulus-related signals. The imaging analyses showed that the posterior parietal cortex (PPC) activated when the participants' gaze was directed towards the salient-objects. By contrast, the right inferior partial cortex was associated with the processing of the target-objects and of distractors that shared the target-color and shape, consistent with goal-directed template-matching operations. The study highlights the possibility of combining measures of gaze orienting and functional imaging to investigate the processing of different types of signals during active behavior in complex environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mapping of MPEG-4 decoding on a flexible architecture platform

NASA Astrophysics Data System (ADS)

van der Tol, Erik B.; Jaspers, Egbert G.

2001-12-01

In the field of consumer electronics, the advent of new features such as Internet, games, video conferencing, and mobile communication has triggered the convergence of television and computers technologies. This requires a generic media-processing platform that enables simultaneous execution of very diverse tasks such as high-throughput stream-oriented data processing and highly data-dependent irregular processing with complex control flows. As a representative application, this paper presents the mapping of a Main Visual profile MPEG-4 for High-Definition (HD) video onto a flexible architecture platform. A stepwise approach is taken, going from the decoder application toward an implementation proposal. First, the application is decomposed into separate tasks with self-contained functionality, clear interfaces, and distinct characteristics. Next, a hardware-software partitioning is derived by analyzing the characteristics of each task such as the amount of inherent parallelism, the throughput requirements, the complexity of control processing, and the reuse potential over different applications and different systems. Finally, a feasible implementation is proposed that includes amongst others a very-long-instruction-word (VLIW) media processor, one or more RISC processors, and some dedicated processors. The mapping study of the MPEG-4 decoder proves the flexibility and extensibility of the media-processing platform. This platform enables an effective HW/SW co-design yielding a high performance density.

Relationships between Task-Oriented Postural Control and Motor Ability in Children and Adolescents with Down Syndrome

ERIC Educational Resources Information Center

Wang, Hui-Yi; Long, I-Man; Liu, Mei-Fang

2012-01-01

Individuals with Down syndrome (DS) have been characterized by greater postural sway in quiet stance and insufficient motor ability. However, there is a lack of studies to explore the properties of dynamic postural sway, especially under conditions of task-oriented movement. The purpose of this study was to investigate the relationships between…

Sustained selective attention predicts flexible switching in preschoolers.

PubMed

Benitez, Viridiana L; Vales, Catarina; Hanania, Rima; Smith, Linda B

2017-04-01

Stability and flexibility are fundamental to an intelligent cognitive system. Here, we examined the relationship between stability in selective attention and explicit control of flexible attention. Preschoolers were tested on the Dimension Preference (DP) task, which measures the stability of selective attention to an implicitly primed dimension, and the Dimension Change Card Sort (DCCS) task, which measures flexible attention switching between dimensions. Children who successfully switched on the DCCS task were more likely than those who perseverated to sustain attention to the primed dimension on the DP task across trials. We propose that perseverators have less stable attention and distribute their attention between dimensions, whereas switchers can successfully stabilize attention to individual dimensions and, thus, show more enduring priming effects. Flexible attention may emerge, in part, from implicit processes that stabilize attention even in tasks not requiring switching. Copyright © 2016 Elsevier Inc. All rights reserved.

Core stability exercise is as effective as task-oriented motor training in improving motor proficiency in children with developmental coordination disorder: a randomized controlled pilot study.

PubMed

Au, Mei K; Chan, Wai M; Lee, Lin; Chen, Tracy Mk; Chau, Rosanna Mw; Pang, Marco Yc

2014-10-01

To compare the effectiveness of a core stability program with a task-oriented motor training program in improving motor proficiency in children with developmental coordination disorder (DCD). Randomized controlled pilot trial. Outpatient unit in a hospital. Twenty-two children diagnosed with DCD aged 6-9 years were randomly allocated to the core stability program or the task-oriented motor program. Both groups underwent their respective face-to-face training session once per week for eight consecutive weeks. They were also instructed to carry out home exercises on a daily basis during the intervention period. Short Form of the Bruininks-Oseretsky Test of Motor Proficiency (Second Edition) and Sensory Organization Test at pre- and post-intervention. Intention-to-treat analysis revealed no significant between-group difference in the change of motor proficiency standard score (P=0.717), and composite equilibrium score derived from the Sensory Organization Test (P=0.100). Further analysis showed significant improvement in motor proficiency in both the core stability (mean change (SD)=6.3(5.4); p=0.008) and task-oriented training groups (mean change(SD)=5.1(4.0); P=0.007). The composite equilibrium score was significantly increased in the task-oriented training group (mean change (SD)=6.0(5.5); P=0.009), but not in the core stability group (mean change(SD) =0.0(9.6); P=0.812). In the task-oriented training group, compliance with the home program was positively correlated with change in motor proficiency (ρ=0.680, P=0.030) and composite equilibrium score (ρ=0.638, P=0.047). The core stability exercise program is as effective as task-oriented training in improving motor proficiency among children with DCD. © The Author(s) 2014.

Let it go: the flexible engagement and disengagement of monitoring processes in a non-focal prospective memory task.

PubMed

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

2017-03-01

Remembering to perform a delayed intention is referred to as prospective memory (PM). In two studies, participants performed an Eriksen flanker task with an embedded PM task (they had to remember to press F1 if a pre-specified cue appeared). In study 1, participants performed a flanker task with either a concurrent PM task or a delayed PM task (instructed to carry out the intention in a later different task). In the delayed PM condition, the PM cues appeared unexpectedly early and we examined whether attention would be captured by the PM cue even though they were not relevant. Results revealed ongoing task costs solely in the concurrent PM condition but no significant task costs in the delayed PM condition showing that attention was not captured by the PM cue when it appeared in an irrelevant context. In study 2, we compared a concurrent PM condition (exactly as in Study 1) to a PM forget condition in which participants were told at a certain point during the flanker task that they no longer had to perform the PM task. Analyses revealed that participants were able to switch off attending to PM cues when instructed to forget the PM task. Results from both studies demonstrate the flexibility of monitoring as evidenced by the presence versus absence of costs in the ongoing flanker task implying that selective attention, like a lens, can be adjusted to attend or ignore, depending on intention relevance.

Central beta-adrenergic modulation of cognitive flexibility.

PubMed

Beversdorf, David Q; White, Dawn M; Chever, Daquesha C; Hughes, John D; Bornstein, Robert A

2002-12-20

Situational stressors and anxiety impede performance on creativity tests requiring cognitive flexibility. Preliminary research revealed better performance on a task requiring cognitive flexibility, the anagram task, after propranolol (beta-adrenergic antagonist) than after ephedrine (beta-adrenergic agonist). However, propranolol and ephedrine have both peripheral and central beta-adrenergic effects. In order to determine whether noradrenergic modulation of cognitive flexibility is a centrally or peripherally mediated phenomenon, we compared the effects of propranolol (peripheral and central beta-blocker), nadolol (peripheral beta-blocker), and placebo on anagram task performance. Solution latency scores for each subject were compared across the drug conditions. Anagram solution latency scores after propranolol were significantly lower than after nadolol. This suggests a centrally mediated modulatory influence of the noradrenergic system on cognitive flexibility.

Effects of activity repetition training with Salat (prayer) versus task oriented training on functional outcomes of stroke.

PubMed

Ghous, Misbah; Malik, Arshad Nawaz; Amjad, Mian Imran; Kanwal, Maria

2017-07-01

Stroke is one of most disabling condition which directly affects quality of life. The objective of this study was to compare the effect of activity repetition training with salat (prayer) versus task oriented training on functional outcomes of stroke. The study design was randomized control trial and 32 patients were randomly assigned into two groups'. The stroke including infarction or haemorrhagic, age bracket 30-70 years was included. The demographics were recorded and standardized assessment tool included Berg Balance Scale (BBS), Motor assessment scale (MAS) and Time Up and Go Test (TUG). The measurements were obtained at baseline, after four and six weeks. The mean age of the patients was 54.44±10.59 years with 16 (59%) male and 11(41%) female patients. Activity Repetition Training group showed significant improvement (p<0.05) and is effective in enhancing the functional status as compare to task oriented training group. The repetition with motivation and concentration is the key in re-learning process of neural plasticity.

Effect of a Task-Oriented Rehabilitation Program on Upper Extremity Recovery Following Motor Stroke

PubMed Central

Winstein, Carolee J.; Wolf, Steven L.; Dromerick, Alexander W.; Lane, Christianne J.; Nelsen, Monica A.; Lewthwaite, Rebecca; Cen, Steven Yong; Azen, Stanley P.

2016-01-01

IMPORTANCE Clinical trials suggest that higher doses of task-oriented training are superior to current clinical practice for patients with stroke with upper extremity motor deficits. OBJECTIVE To compare the efficacy of a structured, task-oriented motor training program vs usual and customary occupational therapy (UCC) during stroke rehabilitation. DESIGN, SETTING, AND PARTICIPANTS Phase 3, pragmatic, single-blind randomized trial among 361 participants with moderate motor impairment recruited from 7 US hospitals over 44 months, treated in the outpatient setting from June 2009 to March 2014. INTERVENTIONS Structured, task-oriented upper extremity training (Accelerated Skill Acquisition Program[ASAP]; n = 119); dose-equivalent occupational therapy (DEUCC; n = 120); or monitoring-only occupational therapy (UCC; n = 122). The DEUCC group was prescribed 30 one-hour sessions over 10 weeks; the UCC group was only monitored, without specification of dose. MAIN OUTCOMES AND MEASURES The primary outcome was 12-month change in log-transformed Wolf Motor Function Test time score (WMFT, consisting of a mean of 15 timed arm movements and hand dexterity tasks). Secondary outcomes were change in WMFT time score (minimal clinically important difference [MCID] = 19 seconds) and proportion of patients improving ≥25 points on the Stroke Impact Scale (SIS) hand function score (MCID = 17.8 points). RESULTS Among the 361 randomized patients (mean age, 60.7 years; 56% men; 42% African American; mean time since stroke onset, 46 days), 304 (84%) completed the 12-month primary outcome assessment; in intention-to-treat analysis, mean group change scores (log WMFT, baseline to 12 months) were, for the ASAP group, 2.2 to 1.4 (difference, 0.82); DEUCC group, 2.0 to 1.2 (difference, 0.84); and UCC group, 2.1 to 1.4 (difference, 0.75), with no significant between-group differences (ASAP vs DEUCC:0.14; 95% CI, −0.05 to 0.33; P = .16; ASAP vs UCC: −0.01; 95% CI, −0.22 to 0.21; P = .94; and

Science Motivation across Asian Countries: Links among Future-Oriented Motivation, Self-Efficacy, Task Values, and Achievement Outcomes

ERIC Educational Resources Information Center

Chang, Yuwen

2015-01-01

The relationships among future-oriented motivation, self-efficacy, task values of science, and achievement outcomes were investigated among 15-year-olds across four Asian nations who participated in the Program for International Student Assessment (PISA) of the Organization for Economic Cooperation and Development (OECD). The factor structure of…

[Action-oriented versus state-oriented reactions to experimenter-induced failures].

PubMed

Brunstein, J C

1989-01-01

The present study assessed different effects of action-oriented versus state-oriented styles of coping with failure on achievement-related performance and cognition. In a learned helplessness experiment, students were exposed to an academic failure situation and were then tested on a series of problem-solving tasks, either immediately after the pretreatment or after a delay of 24 hours. Performance and cognitive concomitants were measured during both experimental periods. Results demonstrated that action orientation was associated with self-immunizing cognitions during helplessness training. Action-oriented participants improved their performance level even after repeated failure feedbacks. Moreover, action-oriented students assigned to the delayed test condition responded with increased striving for success and showed performance increments, even in comparison with control subjects. In contrast, state-oriented participants developed symptoms of helplessness and showed impaired performance during failure inductions. In later tests on problem-solving tasks, state-oriented groups responded with increased fear of failure. Independent of immediate or delayed test conditions, they soon lapsed into new performance decrements.

Single-crystal-like, c-axis oriented BaTiO3 thin films with high-performance on flexible metal templates for ferroelectric applications

NASA Astrophysics Data System (ADS)

Shin, Junsoo; Goyal, Amit; Jesse, Stephen; Kim, Dae Ho

2009-06-01

Epitaxial, c-axis oriented BaTiO3 thin films were deposited using pulsed laser ablation on flexible, polycrystalline Ni alloy tape with biaxially textured oxide buffer multilayers. The high quality of epitaxial BaTiO3 thin films with P4mm group symmetry was confirmed by x-ray diffraction. The microscopic ferroelectric domain structure and the piezoelectric domain switching in these films were confirmed via spatially resolved piezoresponse mapping and local hysteresis loops. Macroscopic measurements demonstrate that the films have well-saturated hysteresis loops with a high remanent polarization of ˜11.5 μC/cm2. Such high-quality, single-crystal-like BaTiO3 films on low-cost, polycrystalline, flexible Ni alloy substrates are attractive for applications in flexible lead-free ferroelectric devices.

Flexible Description Language for HPC based Processing of Remote Sense Data

NASA Astrophysics Data System (ADS)

Nandra, Constantin; Gorgan, Dorian; Bacu, Victor

2016-04-01

When talking about Big Data, the most challenging aspect lays in processing them in order to gain new insight, find new patterns and gain knowledge from them. This problem is likely most apparent in the case of Earth Observation (EO) data. With ever higher numbers of data sources and increasing data acquisition rates, dealing with EO data is indeed a challenge [1]. Geoscientists should address this challenge by using flexible and efficient tools and platforms. To answer this trend, the BigEarth project [2] aims to combine the advantages of high performance computing solutions with flexible processing description methodologies in order to reduce both task execution times and task definition time and effort. As a component of the BigEarth platform, WorDeL (Workflow Description Language) [3] is intended to offer a flexible, compact and modular approach to the task definition process. WorDeL, unlike other description alternatives such as Python or shell scripts, is oriented towards the description topologies, using them as abstractions for the processing programs. This feature is intended to make it an attractive alternative for users lacking in programming experience. By promoting modular designs, WorDeL not only makes the processing descriptions more user-readable and intuitive, but also helps organizing the processing tasks into independent sub-tasks, which can be executed in parallel on multi-processor platforms in order to improve execution times. As a BigEarth platform [4] component, WorDeL represents the means by which the user interacts with the system, describing processing algorithms in terms of existing operators and workflows [5], which are ultimately translated into sets of executable commands. The WorDeL language has been designed to help in the definition of compute-intensive, batch tasks which can be distributed and executed on high-performance, cloud or grid-based architectures in order to improve the processing time. Main references for further

Thinking in Orienteering.

ERIC Educational Resources Information Center

Johansen, Bjorn Tore

1997-01-01

A think-aloud technique, in which 20 orienteers verbalized their exact thoughts during orienteering, was used to examine the phenomenon of cognition during orienteering. Results indicate that orienteering is experienced as a task to be accomplished, a physical movement, and a dynamic process, and that thinking involves attuning perceptions to…

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

PubMed

Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Impaired orienting in youth with Internet Addiction: Evidence from the Attention Network Task (ANT).

PubMed

Fu, Jia; Xu, Peng; Zhao, Lun; Yu, Guoming

2018-06-01

An important theory of attention suggests that there are three separate networks that execute discrete cognitive functions: alerting, orienting and conflict networks. Recent studies showed that there was a dysfunction of attention in Internet Addiction. In order to investigate the underlying mechanism of attention dysfunction in Internet Addiction, we recorded performance related to the Attentional Network Test (ANT) in youth. The ANT, a behavioral assay of the functional integrity of attention networks, was used to examine the performance in Internet Addiction and healthy controls. Performance on the ANT clearly differentiated the participants with and without Internet Addiction in terms of mean reaction times (RTs). Compared with control group, the Internet Addiction group detected targets more slowly and this effect was evident only for spatial cue condition. The Internet Addiction group demonstrated deficits in the orienting network in terms of slower RT. There was no demonstration of a deficit in both the alerting and conflict network in Internet Addiction on this task. The youth with Internet Addiction demonstrated deficits in the orienting network but normal functioning of the alerting and conflict attention networks. Copyright © 2017 Elsevier B.V. All rights reserved.

Pilot modeling and closed-loop analysis of flexible aircraft in the pitch tracking task

NASA Technical Reports Server (NTRS)

Schmidt, D. K.

1983-01-01

The issue addressed in the appropriate modeling technique for pilot vehicle analysis of large flexible aircraft, when the frequency separation between the rigid-body mode and the dynamic aeroelastic modes is reduced. This situation was shown to have significant effects on pitch-tracking performance and subjective rating of the task, obtained via fixed base simulation. Further, the dynamics in these cases are not well modeled with a rigid-body-like model obtained by including only 'static elastic' effects, for example. It is shown that pilot/vehicle analysis of this data supports the hypothesis that an appropriate pilot-model structure is an optimal-control pilot model of full order. This is in contrast to the contention that a representative model is of reduced order when the subject is controlling high-order dynamics as in a flexible vehicle. The key appears to be in the correct assessment of the pilot's objective of attempting to control 'rigid-body' vehicle response, a response that must be estimated by the pilot from observations contaminated by aeroelastic dynamics. Finally, a model-based metric is shown to correlate well with the pilot's subjective ratings.

A task-oriented circuit training in multiple sclerosis: a feasibility study

PubMed Central

2014-01-01

Background The aim of this study was to evaluate the safety, feasibility and preliminary effects of a high-intensity rehabilitative task-oriented circuit training (TOCT) in a sample of multiple sclerosis (MS) subjects on walking competency, mobility, fatigue and health-related quality of life (HRQoL). Methods 24 MS subjects (EDSS 4.89 ± 0.54, 17 female and 7 male, 52.58 ± 11.21 years, MS duration 15.21 ± 8.68 years) have been enrolled and randomly assigned to 2 treatment groups: (i) experimental group received 10 TOCT sessions over 2 weeks (2 hours/each session) followed by a 3 months home exercise program, whereas control group did not receive any specific rehabilitation intervention. A feasibility patient-reported questionnaire was administered after TOCT. Functional outcome measures were: walking endurance (Six Minute Walk Test), gait speed (10 Meter Walk Test), mobility (Timed Up and Go test) and balance (Dynamic Gait Index). Furthermore, self-reported questionnaire of motor fatigue (Fatigue Severity Scale), walking ability (Multiple Sclerosis Walking Scale – 12) and health-related quality of life (Multiple Sclerosis Impact Scale – 29) were included. Subjects’ assessments were delivered at baseline (T0), after TOCT (T1) and 3 months of home-based exercise program (T2). Results After TOCT subjects reported a positive global rating on the received treatment. At 3 months, we found a 58.33% of adherence to the home-exercise program. After TOCT, walking ability and health-related quality of life were improved (p < 0.05) with minor retention after 3 months. The control group showed no significant changes in any variables. Conclusions This two weeks high-intensity task-oriented circuit class training followed by a three months home-based exercise program seems feasible and safe in MS people with moderate mobility impairments; moreover it might improve walking abilities. Trial registration NCT01464749 PMID:24906545

Task-set inertia and memory-consolidation bottleneck in dual tasks.

PubMed

Koch, Iring; Rumiati, Raffaella I

2006-11-01

Three dual-task experiments examined the influence of processing a briefly presented visual object for deferred verbal report on performance in an unrelated auditory-manual reaction time (RT) task. RT was increased at short stimulus-onset asynchronies (SOAs) relative to long SOAs, showing that memory consolidation processes can produce a functional processing bottleneck in dual-task performance. In addition, the experiments manipulated the spatial compatibility of the orientation of the visual object and the side of the speeded manual response. This cross-task compatibility produced relative RT benefits only when the instruction for the visual task emphasized overlap at the level of response codes across the task sets (Experiment 1). However, once the effective task set was in place, it continued to produce cross-task compatibility effects even in single-task situations ("ignore" trials in Experiment 2) and when instructions for the visual task did not explicitly require spatial coding of object orientation (Experiment 3). Taken together, the data suggest a considerable degree of task-set inertia in dual-task performance, which is also reinforced by finding costs of switching task sequences (e.g., AC --> BC vs. BC --> BC) in Experiment 3.

Chimpanzees (Pan troglodytes) display limited behavioural flexibility when faced with a changing foraging task requiring tool use

PubMed Central

Harrison, Rachel A.

2018-01-01

Behavioural flexibility, the ability to alter behaviour in response to environmental feedback, and to relinquish previously successful solutions to problems, is a crucial ability in allowing organisms to adapt to novel environments and environmental change; it is essential to cumulative cultural change. To explore this ability in chimpanzees, 18 individuals (Pan troglodytes) were presented with an artificial foraging task consisting of a tube partially filled with juice that could be reached by hand or retrieved using tool materials to hand. Effective solutions were then restricted in the second phase of the study by narrowing the diameter of the tube, necessitating the abandonment of previously successful solutions. Chimpanzees showed limited behavioural flexibility in comparison to some previous studies, increasing their use of effective techniques, but also continuing to attempt solutions that had been rendered ineffective. This adds to a literature reporting divergent evidence for flexibility (the ability to alter behaviour in response to environmental feedback, and to relinquish previously successful solutions to problems) versus conservatism (a reluctance or inability to explore or adopt novel solutions to problems when a solution is already known) in apes. PMID:29479495

Environmental enrichment enhances cognitive flexibility in C57BL/6 mice on a touchscreen reversal learning task.

PubMed

Zeleznikow-Johnston, Ariel; Burrows, Emma L; Renoir, Thibault; Hannan, Anthony J

2017-05-01

Environmental enrichment (EE) is any positive modification of the 'standard housing' (SH) conditions in which laboratory animals are typically held, usually involving increased opportunity for cognitive stimulation and physical activity. EE has been reported to enhance baseline performance of wild-type animals on traditional cognitive behavioural tasks. Recently, touchscreen operant testing chambers have emerged as a way of performing rodent cognitive assays, providing greater reproducibility, translatability and automatability. Cognitive tests in touchscreen chambers are performed over numerous trials and thus experimenters have the power to detect subtle enhancements in performance. We used touchscreens to analyse the effects of EE on reversal learning, visual discrimination and hippocampal-dependent spatial pattern separation and working memory. We hypothesized that EE would enhance the performance of mice on cognitive touchscreen tasks. Our hypothesis was partially supported in that EE induced enhancements in cognitive flexibility as observed in visual discrimination and reversal learning improvements. However, no other significant effects of EE on cognitive performance were observed. EE decreased the activity level of mice in the touchscreen chambers, which may influence the enrichment level of the animals. Although we did not see enhancements on all hypothesized parameters, our testing paradigm is capable of detecting EE-induced improved cognitive flexibility in mice, which has implications for both understanding the mechanisms of EE and improving screening of putative cognitive-enhancing therapeutics. Copyright © 2017 Elsevier Ltd. All rights reserved.

A cross-cultural comparison of children's imitative flexibility.

PubMed

Clegg, Jennifer M; Legare, Cristine H

2016-09-01

Recent research with Western populations has demonstrated that children use imitation flexibly to engage in both instrumental and conventional learning. Evidence for children's imitative flexibility in non-Western populations is limited, however, and has only assessed imitation of instrumental tasks. This study (N = 142, 6- to 8-year-olds) demonstrates both cultural continuity and cultural variation in imitative flexibility. Children engage in higher imitative fidelity for conventional tasks than for instrumental tasks in both an industrialized, Western culture (United States), and a subsistence-based, non-Western culture (Vanuatu). Children in Vanuatu engage in higher imitative fidelity of instrumental tasks than in the United States, a potential consequence of cultural variation in child socialization for conformity. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Ultrahigh-rate supercapacitors with large capacitance based on edge oriented graphene coated carbonized cellulous paper as flexible freestanding electrodes

NASA Astrophysics Data System (ADS)

Ren, Guofeng; Li, Shiqi; Fan, Zhao-Xia; Hoque, Md Nadim Ferdous; Fan, Zhaoyang

2016-09-01

Large-capacitance and ultrahigh-rate electrochemical supercapacitors (UECs) with frequency response up to kilohertz (kHz) range are reported using light, thin, and flexible freestanding electrodes. The electrode is formed by perpendicularly edge oriented multilayer graphene/thin-graphite (EOG) sheets grown radially around individual fibers in carbonized cellulous paper (CCP), with cellulous carbonization and EOG deposition implemented in one step. The resulted ∼10 μm thick EOG/CCP electrode is light and flexible. The oriented porous structure of EOG with large surface area, in conjunction with high conductivity of the electrode, ensures ultrahigh-rate performance of the fabricated cells, with large areal capacitance of 0.59 mF cm-2 and 0.53 mF cm-2 and large phase angle of -83° and -80° at 120 Hz and 1 kHz, respectively. Particularly, the hierarchical EOG/CCP sheet structure allows multiple sheets stacked together for thick electrodes with almost linearly increased areal capacitance while maintaining the volumetric capacitance nearly no degradation, a critical merit for developing practical faraday-scale UECs. 3-layers of EOG/CCP electrode achieved an areal capacitance of 1.5 mF cm-2 and 1.4 mF cm-2 at 120 Hz and 1 kHz, respectively. This demonstration moves a step closer to the goal of bridging the frequency/capacitance gap between supercapacitors and electrolytic capacitors.

Error affect inoculation for a complex decision-making task.

PubMed

Tabernero, Carmen; Wood, Robert E

2009-05-01

Individuals bring knowledge, implicit theories, and goal orientations to group meetings. Group decisions arise out of the exchange of these orientations. This research explores how a trainee's exploratory and deliberate process (an incremental theory and learning goal orientation) impacts the effectiveness of individual and group decision-making processes. The effectiveness of this training program is compared with another program that included error affect inoculation (EAI). Subjects were 40 Spanish Policemen in a training course. They were distributed in two training conditions for an individual and group decision-making task. In one condition, individuals received the Self-Guided Exploration plus Deliberation Process instructions, which emphasised exploring the options and testing hypotheses. In the other condition, individuals also received instructions based on Error Affect Inoculation (EAI), which emphasised positive affective reactions to errors and mistakes when making decisions. Results show that the quality of decisions increases when the groups share their reasoning. The AIE intervention promotes sharing information, flexible initial viewpoints, and improving the quality of group decisions. Implications and future directions are discussed.

Comparative life cycle assessment of biogas plant configurations for a demand oriented biogas supply for flexible power generation.

PubMed

Hahn, Henning; Hartmann, Kilian; Bühle, Lutz; Wachendorf, Michael

2015-03-01

The environmental performance of biogas plant configurations for a demand - oriented biogas supply for flexible power generation is comparatively assessed in this study. Those configurations indicate an increased energy demand to operate the operational enhancements compared to conventional biogas plants supplying biogas for baseload power generation. However, findings show that in contrast to an alternative supply of power generators with natural gas, biogas supplied on demand by adapted biogas plant configurations saves greenhouse gas emissions by 54-65 g CO(2-eq) MJ(-1) and primary energy by about 1.17 MJ MJ(-1). In this regard, configurations with flexible biogas production profit from reduced biogas storage requirements and achieve higher savings compared to configurations with continuous biogas production. Using thicker biogas storage sheeting material reduces the methane permeability of up to 6m(3) d(-1) which equals a reduction of 8% of the configuration's total methane emissions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Moderation of nicotine effects on covert orienting of attention tasks by poor placebo performance and cue validity.

PubMed

Hammersley, Jonathan J; Gilbert, David G; Rzetelny, Adam; Rabinovich, Norka E

2016-10-01

Given baseline-dependent effects of nicotine on other forms of attention, there is reason to believe that inconsistent findings for the effects of nicotine on attentional orienting may be partly due to individual differences in baseline (abstinence state) functioning. Individuals with low baseline attention may benefit more from nicotine replacement. The effects of nicotine as a function of baseline performance (bottom, middle, and top third of mean reaction times during placebo) were assessed in 52 habitual abstinent smokers (26 females/26 males) utilizing an arrow-cued covert orienting of attention task. Compared to a placebo patch, a 14mg nicotine patch produced faster overall reaction times (RTs). In addition, individuals with slower RTs during the placebo condition benefitted more from nicotine on cued trials than did those who had shorter (faster) RTs during placebo. Nicotine also enhanced the validity effect (shorter RTs to validly vs. invalidly cued targets), but this nicotine benefit did not differ as a function of overall placebo-baseline performance. These findings support the view that nicotine enhances cued spatial attentional orienting in individuals who have slower RTs during placebo (nicotine-free) conditions; however, baseline-dependent effects may not generalize to all aspects of spatial attention. These findings are consistent with findings indicating that nicotine's effects vary as a function of task parameters rather than simple RT speeding or cognitive enhancement. Copyright © 2016 Elsevier Inc. All rights reserved.

Moderation of Nicotine Effects on Covert Orienting of Attention Tasks by Poor Placebo Performance and Cue Validity

PubMed Central

Gilbert, David G.; Rzetelny, Adam; Rabinovich, Norka E.

2016-01-01

Introduction and Rationale Given baseline-dependent effects of nicotine on other forms of attention, there is reason to believe that inconsistent findings for the effects of nicotine on attentional orienting may be partly due to individual differences in baseline (abstinence state) functioning. Individuals with low baseline attention may benefit more from nicotine replacement. Method The effects of nicotine as a function of baseline performance (bottom, middle, and top third of mean reaction times during placebo) were assessed in 52 habitual abstinent smokers (26 females/26 males) utilizing an arrow-cued covert orienting of attention task. Results Compared to a placebo patch, a 14 mg nicotine patch produced faster overall reaction times (RTs). In addition, individuals with slower RTs during the placebo condition benefitted more from nicotine on cued trials than did those who had shorter (faster) RTs during placebo. Nicotine also enhanced the validity effect (shorter RTs to validly vs. invalidly cued targets), but this nicotine benefit did not differ as a function of overall placebo-baseline performance. Conclusions These findings support the view that nicotine enhances cued spatial attentional orienting in individuals who have slower RTs during placebo (nicotine-free) conditions; however, baseline-dependent effects may not generalize to all aspects of spatial attention. These findings are consistent with findings indicating that nicotine’s effects vary as a function of task parameters rather than simple RT speeding or cognitive enhancement. PMID:27461547

Investigating the Relationship between the Perceptions of Taekwondo Athletes towards Coach-Athlete Relationship, Task and Ego Orientation in Sports, and Motivation in Sports

ERIC Educational Resources Information Center

Bezci, Sakir

2016-01-01

This research aims to determine the effect of tasks and egos of taekwondo athletes on the coach-athlete relationship and the effect of coach-athlete relationship on motivation in sports. Thus, "Coach-Athlete Relationship", "Task and Ego Orientation in Sports" and "Motivation in Sports" scales have been applied to the…

Object-oriented sequence analysis: SCL--a C++ class library.

PubMed

Vahrson, W; Hermann, K; Kleffe, J; Wittig, B

1996-04-01

SCL (Sequence Class Library) is a class library written in the C++ programming language. Designed using object-oriented programming principles, SCL consists of classes of objects performing tasks typically needed for analyzing DNA or protein sequences. Among them are very flexible sequence classes, classes accessing databases in various formats, classes managing collections of sequences, as well as classes performing higher-level tasks like calculating a pairwise sequence alignment. SCL also includes classes that provide general programming support, like a dynamically growing array, sets, matrices, strings, classes performing file input/output, and utilities for error handling. By providing these components, SCL fosters an explorative programming style: experimenting with algorithms and alternative implementations is encouraged rather than punished. A description of SCL's overall structure as well as an overview of its classes is given. Important aspects of the work with SCL are discussed in the context of a sample program.

Task Analysis Strategies and Practices. Practice Application Brief.

ERIC Educational Resources Information Center

Brown, Bettina Lankard

Worker-oriented, job-oriented, and cognitive task analyses have all been used as tools for closing the gap between what curriculum teaches and what workers do. Although they share a commonality of purpose, the focus, cost, and practicality of task analysis techniques vary. Worker-oriented task analysis focuses on general human behaviors required…

Task-based learning versus problem-oriented lecture in neurology continuing medical education.

PubMed

Vakani, Farhan; Jafri, Wasim; Ahmad, Amina; Sonawalla, Aziz; Sheerani, Mughis

2014-01-01

To determine whether general practitioners learned better with task-based learning or problem-oriented lecture in a Continuing Medical Education (CME) set-up. Quasi-experimental study. The Aga Khan University, Karachi campus, from April to June 2012. Fifty-nine physicians were given a choice to opt for either Task-based Learning (TBL) or Problem Oriented Lecture (PBL) in a continuing medical education set-up about headaches. The TBL group had 30 participants divided into 10 small groups, and were assigned case-based tasks. The lecture group had 29 participants. Both groups were given a pre and a post-test. Pre/post assessment was done using one-best MCQs. The reliability coefficient of scores for both the groups was estimated through Cronbach's alpha. An item analysis for difficulty and discriminatory indices was calculated for both the groups. Paired t-test was used to determine the difference between pre- and post-test scores of both groups. Independent t-test was used to compare the impact of the two teaching methods in terms of learning through scores produced by MCQ test. Cronbach's alpha was 0.672 for the lecture group and 0.881 for TBL group. Item analysis for difficulty (p) and discriminatory indexes (d) was obtained for both groups. The results for the lecture group showed pre-test (p) = 42% vs. post-test (p) = 43%; pre- test (d) = 0.60 vs. post-test (d) = 0.40. The TBL group showed pre -test (p) = 48% vs. post-test (p) = 70%; pre-test (d) = 0.69 vs. post-test (d) = 0.73. Lecture group pre-/post-test mean scores were (8.52 ± 2.95 vs. 12.41 ± 2.65; p < 0.001), where TBL group showed (9.70 ± 3.65 vs. 14 ± 3.99; p < 0.001). Independent t-test exhibited an insignificant difference at baseline (lecture 8.52 ± 2.95 vs. TBL 9.70 ± 3.65; p = 0.177). The post-scores were not statistically different lecture 12.41 ± 2.65 vs. TBL 14 ± 3.99; p = 0.07). Both delivery methods were found to be equally effective, showing statistically insignificant differences

Staying with the Text: The Contribution of Gender, Achievement Orientations, and Interest to Students' Performance on a Literacy Task

ERIC Educational Resources Information Center

Graham, Jedda; Tisher, Ruth; Ainley, Mary; Kennedy, Gregor

2008-01-01

This study addresses concerns about boys' underperformance on literacy tasks compared to girls, by investigating male and females students' responses to narrative texts. Participants were 142 Grade 9 and 10 students. Achievement orientations, including goals, self-efficacy, and self-handicapping, were measured and approach and avoidance factors…

Task-oriented treadmill exercise training in chronic hemiparetic stroke

PubMed Central

Ivey, Frederick M.; Hafer-Macko, Charlene E.; Macko, Richard F.

2010-01-01

Patients with stroke have elevated hemiparetic gait costs secondary to low activity levels and are often severely deconditioned. Decrements in peak aerobic capacity affect functional ability and cardiovascular-metabolic health and may be partially mediated by molecular changes in hemiparetic skeletal muscle. Conventional rehabilitation is time delimited in the subacute stroke phase and does not provide adequate aerobic intensity to reverse the profound detriments to fitness and function that result from stroke. Hence, we have studied progressive full body weight-support treadmill (TM) training as an adjunct therapy in the chronic stroke phase. Task-oriented TM training has produced measurable changes in fitness, function, and indices of cardiovascular-metabolic health after stroke, but the precise mechanisms for these changes remain under investigation. Further, the optimal dose of this therapy has yet to be identified for individuals with stroke and may vary as a function of deficit severity and outcome goals. This article summarizes the functional and metabolic decline caused by inactivity after stroke and provides current evidence that supports the use of TM training during the chronic stroke phase, with protocols and inclusion/exclusion criteria described. Our research findings are discussed in relation to associated research. PMID:18566943

Self-determination and goal orientation in track and field.

PubMed

Chin, Ngien-Siong; Khoo, Selina; Low, Wah-Yun

2012-06-01

This study investigated gender, age group and locality differences in adolescent athletes' self-determination motivation and goal orientations in track and field. It also examined the relationship between the self-determination theory and achievement goal theory. A total of 632 (349 boys, 283 girls) adolescent athletes (aged 13-18 years) completed the Sports Motivation Scale and Task and Ego Orientation in Sport Questionnaire. Results indicated significant differences between gender on intrinsic motivation, extrinsic motivation, amotivation (t(630) = 4.10, p < 0.05) and ego orientation (t(630) = 2.48, p < 0.05). Male students reported higher intrinsic motivation, extrinsic motivation, amotivation and ego orientation. A significant difference was found between age groups on task orientation (t(630) = 1.94, p < 0.05) and locality on ego orientation (t(630) = 1.94, p < 0.05). Older athletes showed significantly higher task orientation. Rural athletes had higher ego orientation whereas urban athletes have higher intrinsic motivation. Task orientation was related to intrinsic motivation (r = 0.55, p < 0.01), extrinsic motivation (r = 0.55, p < 0.01), but weakly related to amotivation (r = 0.10, p < 0.01). Ego orientation was related to intrinsic motivation (r = 0.30, p < 0.01), extrinsic motivation (r = 0.36, p < 0.01) and amotivaion (r = 0.36, p < 0.01). Task orientation was related to ego orientation (r = 0.29, p < 0.01). Multiple regression analysis showed intrinsic motivation, extrinsic motivation and amotivation accounted for 30.5% of the variances in task orientation.

Self-Determination and Goal Orientation in Track and Field

PubMed Central

Chin, Ngien-Siong; Khoo, Selina; Low, Wah-Yun

2012-01-01

This study investigated gender, age group and locality differences in adolescent athletes’ self-determination motivation and goal orientations in track and field. It also examined the relationship between the self-determination theory and achievement goal theory. A total of 632 (349 boys, 283 girls) adolescent athletes (aged 13–18 years) completed the Sports Motivation Scale and Task and Ego Orientation in Sport Questionnaire. Results indicated significant differences between gender on intrinsic motivation, extrinsic motivation, amotivation (t(630) = 4.10, p < 0.05) and ego orientation (t(630) = 2.48, p < 0.05). Male students reported higher intrinsic motivation, extrinsic motivation, amotivation and ego orientation. A significant difference was found between age groups on task orientation (t(630) = 1.94, p < 0.05) and locality on ego orientation (t(630) = 1.94, p < 0.05). Older athletes showed significantly higher task orientation. Rural athletes had higher ego orientation whereas urban athletes have higher intrinsic motivation. Task orientation was related to intrinsic motivation (r = 0.55, p < 0.01), extrinsic motivation (r = 0.55, p < 0.01), but weakly related to amotivation (r = 0.10, p < 0.01). Ego orientation was related to intrinsic motivation (r = 0.30, p < 0.01), extrinsic motivation (r = 0.36, p < 0.01) and amotivaion (r = 0.36, p < 0.01). Task orientation was related to ego orientation (r = 0.29, p < 0.01). Multiple regression analysis showed intrinsic motivation, extrinsic motivation and amotivation accounted for 30.5% of the variances in task orientation. PMID:23486244

FSD- FLEXIBLE SPACECRAFT DYNAMICS

NASA Technical Reports Server (NTRS)

Fedor, J. V.

1994-01-01

The Flexible Spacecraft Dynamics and Control program (FSD) was developed to aid in the simulation of a large class of flexible and rigid spacecraft. FSD is extremely versatile and can be used in attitude dynamics and control analysis as well as in-orbit support of deployment and control of spacecraft. FSD has been used to analyze the in-orbit attitude performance and antenna deployment of the RAE and IMP class satellites, and the HAWKEYE, SCATHA, EXOS-B, and Dynamics Explorer flight programs. FSD is applicable to inertially-oriented spinning, earth oriented, or gravity gradient stabilized spacecraft. The spacecraft flexibility is treated in a continuous manner (instead of finite element) by employing a series of shape functions for the flexible elements. Torsion, bending, and three flexible modes can be simulated for every flexible element. FSD can handle up to ten tubular elements in an arbitrary orientation. FSD is appropriate for studies involving the active control of pointed instruments, with options for digital PID (proportional, integral, derivative) error feedback controllers and control actuators such as thrusters and momentum wheels. The input to FSD is in four parts: 1) Orbit Construction FSD calculates a Keplerian orbit with environmental effects such as drag, magnetic torque, solar pressure, thermal effects, and thruster adjustments; or the user can supply a GTDS format orbit tape for a particular satellite/time-span; 2) Control words - for options such as gravity gradient effects, control torques, and integration ranges; 3) Mathematical descriptions of spacecraft, appendages, and control systems- including element geometry, properties, attitudes, libration damping, tip mass inertia, thermal expansion, magnetic tracking, and gimbal simulation options; and 4) Desired state variables to output, i.e., geometries, bending moments, fast Fourier transform plots, gimbal rotation, filter vectors, etc. All FSD input is of free format, namelist construction. FSD

Task-oriented training with computer gaming in people with rheumatoid arthritisor osteoarthritis of the hand: study protocol of a randomized controlled pilot trial.

PubMed

Srikesavan, Cynthia Swarnalatha; Shay, Barbara; Robinson, David B; Szturm, Tony

2013-03-09

Significant restriction in the ability to participate in home, work and community life results from pain, fatigue, joint damage, stiffness and reduced joint range of motion and muscle strength in people with rheumatoid arthritis or osteoarthritis of the hand. With modest evidence on the therapeutic effectiveness of conventional hand exercises, a task-oriented training program via real life object manipulations has been developed for people with arthritis. An innovative, computer-based gaming platform that allows a broad range of common objects to be seamlessly transformed into therapeutic input devices through instrumentation with a motion-sense mouse has also been designed. Personalized objects are selected to target specific training goals such as graded finger mobility, strength, endurance or fine/gross dexterous functions. The movements and object manipulation tasks that replicate common situations in everyday living will then be used to control and play any computer game, making practice challenging and engaging. The ongoing study is a 6-week, single-center, parallel-group, equally allocated and assessor-blinded pilot randomized controlled trial. Thirty people with rheumatoid arthritis or osteoarthritis affecting the hand will be randomized to receive either conventional hand exercises or the task-oriented training. The purpose is to determine a preliminary estimation of therapeutic effectiveness and feasibility of the task-oriented training program. Performance based and self-reported hand function, and exercise compliance are the study outcomes. Changes in outcomes (pre to post intervention) within each group will be assessed by paired Student t test or Wilcoxon signed-rank test and between groups (control versus experimental) post intervention using unpaired Student t test or Mann-Whitney U test. The study findings will inform decisions on the feasibility, safety and completion rate and will also provide preliminary data on the treatment effects of the task-oriented

Task-oriented training with computer gaming in people with rheumatoid arthritisor osteoarthritis of the hand: study protocol of a randomized controlled pilot trial

PubMed Central

2013-01-01

Background Significant restriction in the ability to participate in home, work and community life results from pain, fatigue, joint damage, stiffness and reduced joint range of motion and muscle strength in people with rheumatoid arthritis or osteoarthritis of the hand. With modest evidence on the therapeutic effectiveness of conventional hand exercises, a task-oriented training program via real life object manipulations has been developed for people with arthritis. An innovative, computer-based gaming platform that allows a broad range of common objects to be seamlessly transformed into therapeutic input devices through instrumentation with a motion-sense mouse has also been designed. Personalized objects are selected to target specific training goals such as graded finger mobility, strength, endurance or fine/gross dexterous functions. The movements and object manipulation tasks that replicate common situations in everyday living will then be used to control and play any computer game, making practice challenging and engaging. Methods/Design The ongoing study is a 6-week, single-center, parallel-group, equally allocated and assessor-blinded pilot randomized controlled trial. Thirty people with rheumatoid arthritis or osteoarthritis affecting the hand will be randomized to receive either conventional hand exercises or the task-oriented training. The purpose is to determine a preliminary estimation of therapeutic effectiveness and feasibility of the task-oriented training program. Performance based and self-reported hand function, and exercise compliance are the study outcomes. Changes in outcomes (pre to post intervention) within each group will be assessed by paired Student t test or Wilcoxon signed-rank test and between groups (control versus experimental) post intervention using unpaired Student t test or Mann–Whitney U test. Discussion The study findings will inform decisions on the feasibility, safety and completion rate and will also provide preliminary

The Conflict between On-Task and Off-Task Actions in the Classroom and Its Consequences for Motivation and Achievement

ERIC Educational Resources Information Center

Kilian, Britta; Hofer, Manfred; Fries, Stefan; Kuhnle, Claudia

2010-01-01

The relations between students' value orientations, decisions in conflicts between on-task and off-task actions in the classroom, and experiences of motivational interference following these conflicts were investigated. It was expected that well-being value orientation was positively linked and achievement value orientation was negatively linked…

SYFSA: A Framework for Systematic Yet Flexible Systems Analysis

PubMed Central

Johnson, Todd R.; Markowitz, Eliz; Bernstam, Elmer V.; Herskovic, Jorge R.; Thimbleby, Harold

2013-01-01

Although technological or organizational systems that enforce systematic procedures and best practices can lead to improvements in quality, these systems must also be designed to allow users to adapt to the inherent uncertainty, complexity, and variations in healthcare. We present a framework, called Systematic Yet Flexible Systems Analysis (SYFSA) that supports the design and analysis of Systematic Yet Flexible (SYF) systems (whether organizational or technical) by formally considering the tradeoffs between systematicity and flexibility. SYFSA is based on analyzing a task using three related problem spaces: the idealized space, the natural space, and the system space. The idealized space represents the best practice—how the task is to be accomplished under ideal conditions. The natural space captures the task actions and constraints on how the task is currently done. The system space specifies how the task is done in a redesigned system, including how it may deviate from the idealized space, and how the system supports or enforces task constraints. The goal of the framework is to support the design of systems that allow graceful degradation from the idealized space to the natural space. We demonstrate the application of SYFSA for the analysis of a simplified central line insertion task. We also describe several information-theoretic measures of flexibility that can be used to compare alternative designs, and to measure how efficiently a system supports a given task, the relative cognitive workload, and learnability. PMID:23727053

Multiplexer/demultiplexer flexibility enhancement program

NASA Technical Reports Server (NTRS)

1978-01-01

This final report summarizes the accomplishments of the NASA/JSC MDM Flexibility Enhancement Program, Contract NAS9-15359 as carried out by Sperry Flight Systems from April through December 1977. Included are discussions of major statement of work tasks and the results, conclusions and recommended actions. All tasks called out in the amended SOW were carried out. Significant development tasks which were completed included the following: (1) Development, breadboard and test of a Pulse Output 28-volt Module. (2) Development and test of a 32-channel DC Analog Input (DCIN) Differential Module. (3) Development and test of a sequence memory module using an M2708 EPROM which can be programmed in the unit. (4) Development and test of a radiator top cover for a radiation-cooled Flexible MDM.

Task-Induced Development of Hinting Behaviors in Online Task-Oriented L2 Interaction

ERIC Educational Resources Information Center

Balaman, Ufuk

2018-01-01

Technology-mediated task settings are rich interactional domains in which second language (L2) learners manage a multitude of interactional resources for task accomplishment. The affordances of these settings have been repeatedly addressed in computer-assisted language learning (CALL) literature mainly based on theory-informed task design…

Facilitating Goal-Oriented Behaviour in the Stroop Task: When Executive Control Is Influenced by Automatic Processing

PubMed Central

Parris, Benjamin A.; Bate, Sarah; Brown, Scott D.; Hodgson, Timothy L.

2012-01-01

A portion of Stroop interference is thought to arise from a failure to maintain goal-oriented behaviour (or goal neglect). The aim of the present study was to investigate whether goal- relevant primes could enhance goal maintenance and reduce the Stroop interference effect. Here it is shown that primes related to the goal of responding quickly in the Stroop task (e.g. fast, quick, hurry) substantially reduced Stroop interference by reducing reaction times to incongruent trials but increasing reaction times to congruent and neutral trials. No effects of the primes were observed on errors. The effects on incongruent, congruent and neutral trials are explained in terms of the influence of the primes on goal maintenance. The results show that goal priming can facilitate goal-oriented behaviour and indicate that automatic processing can modulate executive control. PMID:23056553

Education, Training and the Flexible Labour Market.

ERIC Educational Resources Information Center

Merson, Martin

1996-01-01

The British government's policy of flexible labor market may be interpreted as either flexibility of conditions, which encourages temporary, contingent work, or flexibility of skills, a repertoire that enables workers to undertake a range of tasks as needed. The challenge for educators is to help workers understand and engage in an uncertain world…

Differences in perceptual learning transfer as a function of training task.

PubMed

Green, C Shawn; Kattner, Florian; Siegel, Max H; Kersten, Daniel; Schrater, Paul R

2015-01-01

A growing body of research--including results from behavioral psychology, human structural and functional imaging, single-cell recordings in nonhuman primates, and computational modeling--suggests that perceptual learning effects are best understood as a change in the ability of higher-level integration or association areas to read out sensory information in the service of particular decisions. Work in this vein has argued that, depending on the training experience, the "rules" for this read-out can either be applicable to new contexts (thus engendering learning generalization) or can apply only to the exact training context (thus resulting in learning specificity). Here we contrast learning tasks designed to promote either stimulus-specific or stimulus-general rules. Specifically, we compare learning transfer across visual orientation following training on three different tasks: an orientation categorization task (which permits an orientation-specific learning solution), an orientation estimation task (which requires an orientation-general learning solution), and an orientation categorization task in which the relevant category boundary shifts on every trial (which lies somewhere between the two tasks above). While the simple orientation-categorization training task resulted in orientation-specific learning, the estimation and moving categorization tasks resulted in significant orientation learning generalization. The general framework tested here--that task specificity or generality can be predicted via an examination of the optimal learning solution--may be useful in building future training paradigms with certain desired outcomes.

Object-oriented Approach to High-level Network Monitoring and Management

NASA Technical Reports Server (NTRS)

Mukkamala, Ravi

2000-01-01

An absolute prerequisite for the management of large investigating methods to build high-level monitoring computer networks is the ability to measure their systems that are built on top of existing monitoring performance. Unless we monitor a system, we cannot tools. Due to the heterogeneous nature of the hope to manage and control its performance. In this underlying systems at NASA Langley Research Center, paper, we describe a network monitoring system that we use an object-oriented approach for the design, we are currently designing and implementing. Keeping, first, we use UML (Unified Modeling Language) to in mind the complexity of the task and the required model users' requirements. Second, we identify the flexibility for future changes, we use an object-oriented existing capabilities of the underlying monitoring design methodology. The system is built using the system. Third, we try to map the former with the latter. APIs offered by the HP OpenView system.

Innovation and behavioral flexibility in wild redfronted lemurs (Eulemur rufifrons).

PubMed

Huebner, Franziska; Fichtel, Claudia

2015-05-01

Innovations and problem-solving abilities can provide animals with important ecological advantages as they allow individuals to deal with novel social and ecological challenges. Innovation is a solution to a novel problem or a novel solution to an old problem, with the latter being especially difficult. Finding a new solution to an old problem requires individuals to inhibit previously applied solutions to invent new strategies and to behave flexibly. We examined the role of experience on cognitive flexibility to innovate and to find new problem-solving solutions with an artificial feeding task in wild redfronted lemurs (Eulemur rufifrons). Four groups of lemurs were tested with feeding boxes, each offering three different techniques to extract food, with only one technique being available at a time. After the subjects learned a technique, this solution was no longer successful and subjects had to invent a new technique. For the first transition between task 1 and 2, subjects had to rely on their experience of the previous technique to solve task 2. For the second transition, subjects had to inhibit the previously learned technique to learn the new task 3. Tasks 1 and 2 were solved by most subjects, whereas task 3 was solved by only a few subjects. In this task, besides behavioral flexibility, especially persistence, i.e., constant trying, was important for individual success during innovation. Thus, wild strepsirrhine primates are able to innovate flexibly, suggesting a general ecological relevance of behavioral flexibility and persistence during innovation and problem solving across all primates.

Functional Specialization and Flexibility in Human Association Cortex

PubMed Central

Yeo, B. T. Thomas; Krienen, Fenna M.; Eickhoff, Simon B.; Yaakub, Siti N.; Fox, Peter T.; Buckner, Randy L.; Asplund, Christopher L.; Chee, Michael W.L.

2015-01-01

The association cortex supports cognitive functions enabling flexible behavior. Here, we explored the organization of human association cortex by mathematically formalizing the notion that a behavioral task engages multiple cognitive components, which are in turn supported by multiple overlapping brain regions. Application of the model to a large data set of neuroimaging experiments (N = 10 449) identified complex zones of frontal and parietal regions that ranged from being highly specialized to highly flexible. The network organization of the specialized and flexible regions was explored with an independent resting-state fMRI data set (N = 1000). Cortical regions specialized for the same components were strongly coupled, suggesting that components function as partially isolated networks. Functionally flexible regions participated in multiple components to different degrees. This heterogeneous selectivity was predicted by the connectivity between flexible and specialized regions. Functionally flexible regions might support binding or integrating specialized brain networks that, in turn, contribute to the ability to execute multiple and varied tasks. PMID:25249407

Sex differences on the judgment of line orientation task: a function of landmark presence and hormonal status.

PubMed

Goyette, Sharon Ramos; McCoy, John G; Kennedy, Ashley; Sullivan, Meghan

2012-02-28

It has been well-established that men outperform women on some spatial tasks. The tools commonly used to demonstrate this difference (e.g. The Mental Rotations Task) typically involve problems and solutions that are presented in a context devoid of referents. The study presented here assessed whether the addition of referents (or "landmarks") would attenuate the well-established sex difference on the judgment of line orientation task (JLOT). Three versions of the JLOT were presented in a within design. The first iteration contained the original JLOT (JLOT 1). JLOT 2 contained three "landmarks" or referents and JLOT 3 contained only one landmark. The sex difference on JLOT 1 was completely negated by the addition of three landmarks on JLOT 2 or the addition of one landmark on JLOT3. In addition, salivary testosterone was measured. In men, gains in performance on the JLOT due to the addition of landmarks were positively correlated with testosterone levels. This suggests that men with the highest testosterone levels benefited the most from the addition of landmarks. These data help to highlight different strategies used by men and women to solve spatial tasks. Copyright © 2011 Elsevier Inc. All rights reserved.

Input-output oriented computation algorithms for the control of large flexible structures

NASA Technical Reports Server (NTRS)

Minto, K. D.

1989-01-01

An overview is given of work in progress aimed at developing computational algorithms addressing two important aspects in the control of large flexible space structures; namely, the selection and placement of sensors and actuators, and the resulting multivariable control law design problem. The issue of sensor/actuator set selection is particularly crucial to obtaining a satisfactory control design, as clearly a poor choice will inherently limit the degree to which good control can be achieved. With regard to control law design, the researchers are driven by concerns stemming from the practical issues associated with eventual implementation of multivariable control laws, such as reliability, limit protection, multimode operation, sampling rate selection, processor throughput, etc. Naturally, the burden imposed by dealing with these aspects of the problem can be reduced by ensuring that the complexity of the compensator is minimized. Our approach to these problems is based on extensions to input/output oriented techniques that have proven useful in the design of multivariable control systems for aircraft engines. In particular, researchers are exploring the use of relative gain analysis and the condition number as a means of quantifying the process of sensor/actuator selection and placement for shape control of a large space platform.

Object-Oriented Design for Sparse Direct Solvers

NASA Technical Reports Server (NTRS)

Dobrian, Florin; Kumfert, Gary; Pothen, Alex

1999-01-01

We discuss the object-oriented design of a software package for solving sparse, symmetric systems of equations (positive definite and indefinite) by direct methods. At the highest layers, we decouple data structure classes from algorithmic classes for flexibility. We describe the important structural and algorithmic classes in our design, and discuss the trade-offs we made for high performance. The kernels at the lower layers were optimized by hand. Our results show no performance loss from our object-oriented design, while providing flexibility, case of use, and extensibility over solvers using procedural design.

The Effect of Positive Mood on Flexible Processing of Affective Information.

PubMed

Grol, Maud; De Raedt, Rudi

2017-07-17

Recent efforts have been made to understand the cognitive mechanisms underlying psychological resilience. Cognitive flexibility in the context of affective information has been related to individual differences in resilience. However, it is unclear whether flexible affective processing is sensitive to mood fluctuations. Furthermore, it remains to be investigated how effects on flexible affective processing interact with the affective valence of information that is presented. To fill this gap, we tested the effects of positive mood and individual differences in self-reported resilience on affective flexibility, using a task switching paradigm (N = 80). The main findings showed that positive mood was related to lower task switching costs, reflecting increased flexibility, in line with previous findings. In line with this effect of positive mood, we showed that greater resilience levels, specifically levels of acceptance of self and life, also facilitated task set switching in the context of affective information. However, the effects of resilience on affective flexibility seem more complex. Resilience tended to relate to more efficient task switching when negative information was preceded by positive information, possibly because the presentation of positive information, as well as positive mood, can facilitate task set switching. Positive mood also influenced costs associated with switching affective valence of the presented information. This latter effect was indicative of a reduced impact of no longer relevant negative information and more impact of no longer relevant positive information. Future research should confirm these effects of individual differences in resilience on affective flexibility, considering the affective valence of the presented information. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Action versus Result-Oriented Schemes in a Grassland Agroecosystem: A Dynamic Modelling Approach

PubMed Central

Sabatier, Rodolphe; Doyen, Luc; Tichit, Muriel

2012-01-01

Effects of agri-environment schemes (AES) on biodiversity remain controversial. While most AES are action-oriented, result-oriented and habitat-oriented schemes have recently been proposed as a solution to improve AES efficiency. The objective of this study was to compare action-oriented, habitat-oriented and result-oriented schemes in terms of ecological and productive performance as well as in terms of management flexibility. We developed a dynamic modelling approach based on the viable control framework to carry out a long term assessment of the three schemes in a grassland agroecosystem. The model explicitly links grazed grassland dynamics to bird population dynamics. It is applied to lapwing conservation in wet grasslands in France. We ran the model to assess the three AES scenarios. The model revealed the grazing strategies respecting ecological and productive constraints specific to each scheme. Grazing strategies were assessed by both their ecological and productive performance. The viable control approach made it possible to obtain the whole set of viable grazing strategies and therefore to quantify the management flexibility of the grassland agroecosystem. Our results showed that habitat and result-oriented scenarios led to much higher ecological performance than the action-oriented one. Differences in both ecological and productive performance between the habitat and result-oriented scenarios were limited. Flexibility of the grassland agroecosystem in the result-oriented scenario was much higher than in that of habitat-oriented scenario. Our model confirms the higher flexibility as well as the better ecological and productive performance of result-oriented schemes. A larger use of result-oriented schemes in conservation may also allow farmers to adapt their management to local conditions and to climatic variations. PMID:22496746

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

PubMed

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

2010-09-01

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

Task-dependent recurrent dynamics in visual cortex

PubMed Central

Tajima, Satohiro; Koida, Kowa; Tajima, Chihiro I; Suzuki, Hideyuki; Aihara, Kazuyuki; Komatsu, Hidehiko

2017-01-01

The capacity for flexible sensory-action association in animals has been related to context-dependent attractor dynamics outside the sensory cortices. Here, we report a line of evidence that flexibly modulated attractor dynamics during task switching are already present in the higher visual cortex in macaque monkeys. With a nonlinear decoding approach, we can extract the particular aspect of the neural population response that reflects the task-induced emergence of bistable attractor dynamics in a neural population, which could be obscured by standard unsupervised dimensionality reductions such as PCA. The dynamical modulation selectively increases the information relevant to task demands, indicating that such modulation is beneficial for perceptual decisions. A computational model that features nonlinear recurrent interaction among neurons with a task-dependent background input replicates the key properties observed in the experimental data. These results suggest that the context-dependent attractor dynamics involving the sensory cortex can underlie flexible perceptual abilities. DOI: http://dx.doi.org/10.7554/eLife.26868.001 PMID:28737487

Second-order motor planning in children: insights from a cup-manipulation-task.

PubMed

Wunsch, Kathrin; Weiss, Daniel J; Schack, Thomas; Weigelt, Matthias

2015-07-01

The present study examined the development of anticipatory motor planning in an object manipulation task that has been used to successfully demonstrate motor planning in non-human primates (Weiss et al. in Psychol Sci 18:1063-1068, 2007). Seventy-five participants from four different age groups participated in a cup-manipulation task. One group was preschool children (average age of 5.1 years), two groups were primary school children (7.7 and 9.8 years old respectively) and the final group was comprised of adults. The experimental task entailed reaching for a plastic cup that was vertically suspended in an apparatus in either upright or inverted orientation, removing the cup by its stem and then retrieving a small toy from the inside of the cup. When the cup was inverted in the apparatus, evidence for anticipatory motor planning could be achieved by initially gripping the stem using an inverted (thumb-down) grip posture. We found that when the cup was in upright orientation, all participants reached for the cup using an upright grip (i.e., thumb-up posture). However, when the cup was inverted in the apparatus, only adults consistently used an inverted grasping posture, though the percentage of inverted grips among participants did increase with age. These results suggest a protracted development for anticipatory motor planning abilities in children. Surprisingly, the performance of adults on this task more closely resembles the performance of several nonhuman primate species as opposed to children even at approximately 10 years of age. We discuss how morphological constraints on flexibility may help account for these findings.

The Negative Impact of Goal-Oriented Instructions

ERIC Educational Resources Information Center

Shatz, Itamar

2015-01-01

The phrasing of task instructions can facilitate or hinder the learning process. In this study, three groups of participants (N = 526) performed a foreign vocabulary memorization task, with modified instructions for each group. The instructions were either learning oriented, encouraging participants to improve their abilities; outcome oriented,…

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

PubMed

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

2016-05-15

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

Task Effects Reveal Cognitive Flexibility Responding to Frequency and Predictability: Evidence from Eye Movements in Reading and Proofreading

PubMed Central

Schotter, Elizabeth R.; Bicknell, Klinton; Howard, Ian; Levy, Roger; Rayner, Keith

2014-01-01

It is well-known that word frequency and predictability affect processing time. These effects change magnitude across tasks, but studies testing this use tasks with different response types (e.g., lexical decision, naming, and fixation time during reading; Schilling, Rayner & Chumbley, 1998), preventing direct comparison. Recently, Kaakinen and Hyönä (2010) overcame this problem, comparing fixation times in reading for comprehension and proofreading, showing that the frequency effect was larger in proofreading than in reading. This result could be explained by readers exhibiting substantial cognitive flexibility, and qualitatively changing how they process words in the proofreading task in a way that magnifies effects of word frequency. Alternatively, readers may not change word processing so dramatically, and instead may perform more careful identification generally, increasing the magnitude of many word processing effects (e.g., both frequency and predictability). We tested these possibilities with two experiments: subjects read for comprehension and then proofread for spelling errors (letter transpositions) that produce nonwords (e.g., trcak for track as in Kaakinen & Hyönä) or that produce real but unintended words (e.g., trial for trail) to compare how the task changes these effects. Replicating Kaakinen and Hyönä, frequency effects increased during proofreading. However, predictability effects only increased when integration with the sentence context was necessary to detect errors (i.e., when spelling errors produced words that were inappropriate in the sentence; trial for trail). The results suggest that readers adopt sophisticated word processing strategies to accommodate task demands. PMID:24434024

Flexible ligand docking using a genetic algorithm

NASA Astrophysics Data System (ADS)

Oshiro, C. M.; Kuntz, I. D.; Dixon, J. Scott

1995-04-01

Two computational techniques have been developed to explore the orientational and conformational space of a flexible ligand within an enzyme. Both methods use the Genetic Algorithm (GA) to generate conformationally flexible ligands in conjunction with algorithms from the DOCK suite of programs to characterize the receptor site. The methods are applied to three enzyme-ligand complexes: dihydrofolate reductase-methotrexate, thymidylate synthase-phenolpthalein and HIV protease-thioketal haloperidol. Conformations and orientations close to the crystallographically determined structures are obtained, as well as alternative structures with low energy. The potential for the GA method to screen a database of compounds is also examined. A collection of ligands is evaluated simultaneously, rather than docking the ligands individually into the enzyme.

A flexible, high-performance magnetoelectric heterostructure of (001) oriented Pb(Zr0.52Ti0.48)O3 film grown on Ni foil

NASA Astrophysics Data System (ADS)

Palneedi, Haribabu; Yeo, Hong Goo; Hwang, Geon-Tae; Annapureddy, Venkateswarlu; Kim, Jong-Woo; Choi, Jong-Jin; Trolier-McKinstry, Susan; Ryu, Jungho

2017-09-01

In this study, a flexible magnetoelectric (ME) heterostructure of PZT/Ni was fabricated by depositing a (001) oriented Pb(Zr0.52Ti0.48)O3 (PZT) film on a thin, flexible Ni foil buffered with LaNiO3/HfO2. Excellent ferroelectric properties and large ME voltage coefficient of 3.2 V/cmṡOe were realized from the PZT/Ni heterostructure. The PZT/Ni composite's high performance was attributed to strong texturing of the PZT film, coupled with the compressive stress in the piezoelectric film. Besides, reduced substrate clamping in the PZT film due to the film on the foil structure and strong interfacial bonding in the PZT/LaNiO3/HfO2/Ni heterostructure could also have contributed to the high ME performance of PZT/Ni.

Contingency theoretic methodology for agent-based web-oriented manufacturing systems

NASA Astrophysics Data System (ADS)

Durrett, John R.; Burnell, Lisa J.; Priest, John W.

2000-12-01

The development of distributed, agent-based, web-oriented, N-tier Information Systems (IS) must be supported by a design methodology capable of responding to the convergence of shifts in business process design, organizational structure, computing, and telecommunications infrastructures. We introduce a contingency theoretic model for the use of open, ubiquitous software infrastructure in the design of flexible organizational IS. Our basic premise is that developers should change in the way they view the software design process from a view toward the solution of a problem to one of the dynamic creation of teams of software components. We postulate that developing effective, efficient, flexible, component-based distributed software requires reconceptualizing the current development model. The basic concepts of distributed software design are merged with the environment-causes-structure relationship from contingency theory; the task-uncertainty of organizational- information-processing relationships from information processing theory; and the concept of inter-process dependencies from coordination theory. Software processes are considered as employees, groups of processes as software teams, and distributed systems as software organizations. Design techniques already used in the design of flexible business processes and well researched in the domain of the organizational sciences are presented. Guidelines that can be utilized in the creation of component-based distributed software will be discussed.

Flexible Composite-Material Pressure Vessel

NASA Technical Reports Server (NTRS)

Brown, Glen; Haggard, Roy; Harris, Paul A.

2003-01-01

A proposed lightweight pressure vessel would be made of a composite of high-tenacity continuous fibers and a flexible matrix material. The flexibility of this pressure vessel would render it (1) compactly stowable for transport and (2) more able to withstand impacts, relative to lightweight pressure vessels made of rigid composite materials. The vessel would be designed as a structural shell wherein the fibers would be predominantly bias-oriented, the orientations being optimized to make the fibers bear the tensile loads in the structure. Such efficient use of tension-bearing fibers would minimize or eliminate the need for stitching and fill (weft) fibers for strength. The vessel could be fabricated by techniques adapted from filament winding of prior composite-material vessels, perhaps in conjunction with the use of dry film adhesives. In addition to the high-bias main-body substructure described above, the vessel would include a low-bias end substructure to complete coverage and react peak loads. Axial elements would be overlaid to contain damage and to control fiber orientation around side openings. Fiber ring structures would be used as interfaces for connection to ancillary hardware.

Flexibility in data interpretation: effects of representational format.

PubMed

Braithwaite, David W; Goldstone, Robert L

2013-01-01

Graphs and tables differentially support performance on specific tasks. For tasks requiring reading off single data points, tables are as good as or better than graphs, while for tasks involving relationships among data points, graphs often yield better performance. However, the degree to which graphs and tables support flexibility across a range of tasks is not well-understood. In two experiments, participants detected main and interaction effects in line graphs and tables of bivariate data. Graphs led to more efficient performance, but also lower flexibility, as indicated by a larger discrepancy in performance across tasks. In particular, detection of main effects of variables represented in the graph legend was facilitated relative to detection of main effects of variables represented in the x-axis. Graphs may be a preferable representational format when the desired task or analytical perspective is known in advance, but may also induce greater interpretive bias than tables, necessitating greater care in their use and design.

Flexibility in data interpretation: effects of representational format

PubMed Central

Braithwaite, David W.; Goldstone, Robert L.

2013-01-01

Graphs and tables differentially support performance on specific tasks. For tasks requiring reading off single data points, tables are as good as or better than graphs, while for tasks involving relationships among data points, graphs often yield better performance. However, the degree to which graphs and tables support flexibility across a range of tasks is not well-understood. In two experiments, participants detected main and interaction effects in line graphs and tables of bivariate data. Graphs led to more efficient performance, but also lower flexibility, as indicated by a larger discrepancy in performance across tasks. In particular, detection of main effects of variables represented in the graph legend was facilitated relative to detection of main effects of variables represented in the x-axis. Graphs may be a preferable representational format when the desired task or analytical perspective is known in advance, but may also induce greater interpretive bias than tables, necessitating greater care in their use and design. PMID:24427145

NMDA and D2-like receptors modulate cognitive flexibility in a color discrimination reversal task in pigeons.

PubMed

Herold, Christina

2010-06-01

Reversal and extinction learning represent forms of cognitive flexibility that refer to the ability of an animal to alter behavior in response to unanticipated changes on environmental demands. A role for dopamine and glutamate in modulating this behavior has been implicated. Here, we determined the effects of intracerebroventricular injections in pigeons' forebrain of the D2-like receptor agonist quinpirole, the D2-like receptor antagonist sulpiride and the N-methyl-d-aspartate receptor antagonist AP-5 on initial acquisition and reversal of a color discrimination task. On day one, pigeons had to learn to discriminate two color keys. On day two, pigeons first performed a retention test, which was followed by a reversal of the reward contingencies of the two color keys. None of the drugs altered performance in the initial acquisition of color discrimination or affected the retention of the learned color key. In contrast, all drugs impaired reversal learning by increasing trials and incorrect responses in the reversal session. Our data support the hypothesis that D2-like receptor mechanisms, like N-methyl-d-aspartate receptor modulations, are involved in cognitive flexibility and relearning processes, but not in initial learning of stimulus-reward association.

Stochastic Dynamics Underlying Cognitive Stability and Flexibility

PubMed Central

Ueltzhöffer, Kai; Armbruster-Genç, Diana J. N.; Fiebach, Christian J.

2015-01-01

Cognitive stability and flexibility are core functions in the successful pursuit of behavioral goals. While there is evidence for a common frontoparietal network underlying both functions and for a key role of dopamine in the modulation of flexible versus stable behavior, the exact neurocomputational mechanisms underlying those executive functions and their adaptation to environmental demands are still unclear. In this work we study the neurocomputational mechanisms underlying cue based task switching (flexibility) and distractor inhibition (stability) in a paradigm specifically designed to probe both functions. We develop a physiologically plausible, explicit model of neural networks that maintain the currently active task rule in working memory and implement the decision process. We simplify the four-choice decision network to a nonlinear drift-diffusion process that we canonically derive from a generic winner-take-all network model. By fitting our model to the behavioral data of individual subjects, we can reproduce their full behavior in terms of decisions and reaction time distributions in baseline as well as distractor inhibition and switch conditions. Furthermore, we predict the individual hemodynamic response timecourse of the rule-representing network and localize it to a frontoparietal network including the inferior frontal junction area and the intraparietal sulcus, using functional magnetic resonance imaging. This refines the understanding of task-switch-related frontoparietal brain activity as reflecting attractor-like working memory representations of task rules. Finally, we estimate the subject-specific stability of the rule-representing attractor states in terms of the minimal action associated with a transition between different rule states in the phase-space of the fitted models. This stability measure correlates with switching-specific thalamocorticostriatal activation, i.e., with a system associated with flexible working memory updating and

A flexible object-oriented software framework for developing complex multimedia simulations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sydelko, P. J.; Dolph, J. E.; Christiansen, J. H.

Decision makers involved in brownfields redevelopment and long-term stewardship must consider environmental conditions, future-use potential, site ownership, area infrastructure, funding resources, cost recovery, regulations, risk and liability management, community relations, and expected return on investment in a comprehensive and integrated fashion to achieve desired results. Successful brownfields redevelopment requires the ability to assess the impacts of redevelopment options on multiple interrelated aspects of the ecosystem, both natural and societal. Computer-based tools, such as simulation models, databases, and geographical information systems (GISs) can be used to address brownfields planning and project execution. The transparent integration of these tools into a comprehensivemore » and dynamic decision support system would greatly enhance the brownfields assessment process. Such a system needs to be able to adapt to shifting and expanding analytical requirements and contexts. The Dynamic Information Architecture System (DIAS) is a flexible, extensible, object-oriented framework for developing and maintaining complex multidisciplinary simulations of a wide variety of application domains. The modeling domain of a specific DIAS-based simulation is determined by (1) software objects that represent the real-world entities that comprise the problem space (atmosphere, watershed, human), and (2) simulation models and other data processing applications that express the dynamic behaviors of the domain entities. Models and applications used to express dynamic behaviors can be either internal or external to DIAS, including existing legacy models written in various languages (FORTRAN, C, etc.). The flexible design framework of DIAS makes the objects adjustable to the context of the problem without a great deal of recoding. The DIAS Spatial Data Set facility allows parameters to vary spatially depending on the simulation context according to any of a number of 1-D

There's more to care than tasks.

PubMed

O'Dwyer, Sheena

2009-07-09

Task orientation is a phrase that is used to demonstrate how not to give care. It is the antithesis of person-centred treatment. I care for people with dementia, working on a ward that is often severely understaffed (sound familiar?) and sometimes I go home wondering how my team and I could have done anything other than be task orientated.

A crystalline germanium flexible thin-film transistor

NASA Astrophysics Data System (ADS)

Higashi, H.; Nakano, M.; Kudo, K.; Fujita, Y.; Yamada, S.; Kanashima, T.; Tsunoda, I.; Nakashima, H.; Hamaya, K.

2017-11-01

We experimentally demonstrate a flexible thin-film transistor (TFT) with (111)-oriented crystalline germanium (Ge) layers grown by a gold-induced crystallization method. Accumulation-mode metal source/drain p-channel Ge TFTs are fabricated on a polyimide film at ≤ 400 ° C . A field-effect mobility (μFE) of 10.7 cm2/Vs is obtained, meaning the highest μFE in the p-TFTs fabricated at ≤ 400 ° C on flexible plastic substrates. This study will lead to high-performance flexible electronics based on an inorganic-semiconductor channel.

Effects of mirror therapy integrated with task-oriented exercise on the balance function of patients with poststroke hemiparesis: a randomized-controlled pilot trial.

PubMed

Cha, Hyun-Gyu; Oh, Duck-Won

2016-03-01

This study aimed to explore the effects of mirror therapy integrated with task-oriented exercise on balance function in poststroke hemiparesis. Twenty patients with poststroke hemiparesis were assigned randomly to an experimental group (EG) and a control group (CG), with 10 individuals each. Participants of the EG and CG received a task-oriented exercise program with a focus on the strengthening of the lower limb and the practice of balance-related functional tasks. An additional option for the EG was front and side wall mirrors to provide visual feedback for their own movements while performing the exercise. The program was performed for 30 min, twice a day, five times per week for 4 weeks. Outcome measures included the Berg balance scale, the timed up-and-go test, and quantitative data (balance index and dynamic limits of stability). In the EG and CG, all variables showed significant differences between pretest and post-test (P<0.05), and post-test values of all variables appeared to be significantly different between two groups (P<0.05). Furthermore, in the EG, the change values between pretest and post-test values of Berg balance scale (13.00±3.20 vs. 6.60±4.55 scores), and timed up-and-go test (6.45±3.00 vs. 3.61±1.84 s), balance index (2.29±0.51 vs. 0.96±0.65 scores), dynamic limits of stability (7.70±3.83 vs. 3.70±4.60 scores) were significantly higher than those of the CG (P<0.05). The findings suggest that a mirror therapy may be used as a beneficial therapeutic option to facilitate the effects of a task-oriented exercise on balance function of patients with poststroke hemiparesis.

The Use of Music to Increase Task-Oriented Behaviors in Preschool Children with Autism Spectrum Disorders in a Gross Motor Setting

ERIC Educational Resources Information Center

Dieringer, Shannon M.

2012-01-01

The purpose of this study is to determine the effect of music and music + instruction on task-oriented behaviors in preschool children with ASD within individual gross motor movement settings. Five preschool children (four boys; one girl) diagnosed with ASD attending a Midwestern private preschool for children with ASD served as participants. The…

Self-Handicapping Prior to Academic-Oriented Tasks in Children with Attention Deficit/Hyperactivity Disorder (ADHD): Medication Effects and Comparisons with Controls

ERIC Educational Resources Information Center

Waschbusch, Daniel A.; Craig, Rebecca; Pelham, William E., Jr.; King, Sara

2007-01-01

The authors examined self-handicapping prior to academic-oriented tasks in children with and without ADHD and examined whether stimulant medication influenced self-handicapping. Participants were 61 children ages 6 to 13, including 22 children with ADHD tested after taking a placebo, 21 children with ADHD tested after taking stimulant medication,…

Auditory orienting of attention: Effects of cues and verbal workload with children and adults.

PubMed

Phélip, Marion; Donnot, Julien; Vauclair, Jacques

2016-01-01

The use of tone cues has an improving effect on the auditory orienting of attention for children as for adults. Verbal cues, on the contrary, do not seem to orient attention as efficiently before the age of 9 years. However, several studies have reported inconsistent effects of orienting attention on ear asymmetries. Multiple factors are questioned, such as the role of verbal workload. Indeed, the semantic nature of the dichotic pairs and their load of processing may explain orienting of attention performance. Thus, by controlling for the role of verbal workload, the present experiment aimed to evaluate the development of capacities for the auditory orienting of attention. Right-handed, 6- to 12-year-olds and adults were recruited to complete either a tone cue or a verbal cue dichotic listening task in the identification of familiar words or nonsense words. A factorial design analysis of variance showed a significant right-ear advantage for all the participants and for all the types of stimuli. A major developmental effect was observed in which verbal cues played an important role: they allowed the 6- to 8-year-olds to improve their performance of identification in the left ear. These effects were taken as evidence of the implication of top-down processes in cognitive flexibility across development.

Brain Signal Variability Differentially Affects Cognitive Flexibility and Cognitive Stability.

PubMed

Armbruster-Genç, Diana J N; Ueltzhöffer, Kai; Fiebach, Christian J

2016-04-06

Recent research yielded the intriguing conclusion that, in healthy adults, higher levels of variability in neuronal processes are beneficial for cognitive functioning. Beneficial effects of variability in neuronal processing can also be inferred from neurocomputational theories of working memory, albeit this holds only for tasks requiring cognitive flexibility. However, cognitive stability, i.e., the ability to maintain a task goal in the face of irrelevant distractors, should suffer under high levels of brain signal variability. To directly test this prediction, we studied both behavioral and brain signal variability during cognitive flexibility (i.e., task switching) and cognitive stability (i.e., distractor inhibition) in a sample of healthy human subjects and developed an efficient and easy-to-implement analysis approach to assess BOLD-signal variability in event-related fMRI task paradigms. Results show a general positive effect of neural variability on task performance as assessed by accuracy measures. However, higher levels of BOLD-signal variability in the left inferior frontal junction area result in reduced error rate costs during task switching and thus facilitate cognitive flexibility. In contrast, variability in the same area has a detrimental effect on cognitive stability, as shown in a negative effect of variability on response time costs during distractor inhibition. This pattern was mirrored at the behavioral level, with higher behavioral variability predicting better task switching but worse distractor inhibition performance. Our data extend previous results on brain signal variability by showing a differential effect of brain signal variability that depends on task context, in line with predictions from computational theories. Recent neuroscientific research showed that the human brain signal is intrinsically variable and suggested that this variability improves performance. Computational models of prefrontal neural networks predict differential

Monetary rewards influence retrieval orientations.

PubMed

Halsband, Teresa M; Ferdinand, Nicola K; Bridger, Emma K; Mecklinger, Axel

2012-09-01

Reward anticipation during learning is known to support memory formation, but its role in retrieval processes is so far unclear. Retrieval orientations, as a reflection of controlled retrieval processing, are one aspect of retrieval that might be modulated by reward. These processes can be measured using the event-related potentials (ERPs) elicited by retrieval cues from tasks with different retrieval requirements, such as via changes in the class of targeted memory information. To determine whether retrieval orientations of this kind are modulated by reward during learning, we investigated the effects of high and low reward expectancy on the ERP correlates of retrieval orientation in two separate experiments. The reward manipulation at study in Experiment 1 was associated with later memory performance, whereas in Experiment 2, reward was directly linked to accuracy in the study task. In both studies, the participants encoded mixed lists of pictures and words preceded by high- or low-reward cues. After 24 h, they performed a recognition memory exclusion task, with words as the test items. In addition to a previously reported material-specific effect of retrieval orientation, a frontally distributed, reward-associated retrieval orientation effect was found in both experiments. These findings suggest that reward motivation during learning leads to the adoption of a reward-associated retrieval orientation to support the retrieval of highly motivational information. Thus, ERP retrieval orientation effects not only reflect retrieval processes related to the sought-for materials, but also relate to the reward conditions with which items were combined during encoding.

Modular C3 Interface Analysis (Flexible Intraconnect). Volume 1, Part 1

DTIC Science & Technology

1980-04-01

was prepared in parallel with a separate Flexible^ Intraconnect design definition study conducted by Hughes Aircraft Company under F19628-77-O-0261...reported herein consists of Task I, Task II, and Task III of Phase I of an on-going study being conducted by the Air Force to develop a Flexible...Intraconnect for tactical C^ tivity. equipment connec- As evidenced by the quantity of analyses performed and docu- mented during the period of this study

Flexible thermal apparatus for mounting of thermoelectric cooler

NASA Technical Reports Server (NTRS)

Jones, Jack A. (Inventor); Petrick, S. Walter (Inventor); Bard, Steven (Inventor)

1991-01-01

A flexible heat transfer apparatus used to flexibly connect and thermally couple a thermoelectric cooler to an object to be cooled is disclosed. The flexible heat transfer apparatus consists of a pair of flexible corrugated sheets made from high thermal conductivity materials such as copper, aluminum, gold, or silver. The ridges of the corrugated sheets are oriented perpendicular to one another and bonded sandwich-fashion between three plates to define an upper section and a lower section. The upper section provides X flexure, the lower section provides Y flexure, and both sections together provide Z flexure.

Task effects reveal cognitive flexibility responding to frequency and predictability: evidence from eye movements in reading and proofreading.

PubMed

Schotter, Elizabeth R; Bicknell, Klinton; Howard, Ian; Levy, Roger; Rayner, Keith

2014-04-01

It is well-known that word frequency and predictability affect processing time. These effects change magnitude across tasks, but studies testing this use tasks with different response types (e.g., lexical decision, naming, and fixation time during reading; Schilling, Rayner, & Chumbley, 1998), preventing direct comparison. Recently, Kaakinen and Hyönä (2010) overcame this problem, comparing fixation times in reading for comprehension and proofreading, showing that the frequency effect was larger in proofreading than in reading. This result could be explained by readers exhibiting substantial cognitive flexibility, and qualitatively changing how they process words in the proofreading task in a way that magnifies effects of word frequency. Alternatively, readers may not change word processing so dramatically, and instead may perform more careful identification generally, increasing the magnitude of many word processing effects (e.g., both frequency and predictability). We tested these possibilities with two experiments: subjects read for comprehension and then proofread for spelling errors (letter transpositions) that produce nonwords (e.g., trcak for track as in Kaakinen & Hyönä) or that produce real but unintended words (e.g., trial for trail) to compare how the task changes these effects. Replicating Kaakinen and Hyönä, frequency effects increased during proofreading. However, predictability effects only increased when integration with the sentence context was necessary to detect errors (i.e., when spelling errors produced words that were inappropriate in the sentence; trial for trail). The results suggest that readers adopt sophisticated word processing strategies to accommodate task demands. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Deep Thinking Increases Task-Set Shielding and Reduces Shifting Flexibility in Dual-Task Performance

ERIC Educational Resources Information Center

Fischer, Rico; Hommel, Bernhard

2012-01-01

Performing two tasks concurrently is difficult, which has been taken to imply the existence of a structural processing bottleneck. Here we sought to assess whether and to what degree one's multitasking abilities depend on the cognitive-control style one engages in. Participants were primed with creativity tasks that either called for divergent…

Parietal and frontal object areas underlie perception of object orientation in depth.

PubMed

Niimi, Ryosuke; Saneyoshi, Ayako; Abe, Reiko; Kaminaga, Tatsuro; Yokosawa, Kazuhiko

2011-05-27

Recent studies have shown that the human parietal and frontal cortices are involved in object image perception. We hypothesized that the parietal/frontal object areas play a role in differentiating the orientations (i.e., views) of an object. By using functional magnetic resonance imaging, we compared brain activations while human observers differentiated between two object images in depth-orientation (orientation task) and activations while they differentiated the images in object identity (identity task). The left intraparietal area, right angular gyrus, and right inferior frontal areas were activated more for the orientation task than for the identity task. The occipitotemporal object areas, however, were activated equally for the two tasks. No region showed greater activation for the identity task. These results suggested that the parietal/frontal object areas encode view-dependent visual features and underlie object orientation perception. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Mental-orientation: A new approach to assessing patients across the Alzheimer's disease spectrum.

PubMed

Peters-Founshtein, Gregory; Peer, Michael; Rein, Yanai; Kahana Merhavi, Shlomzion; Meiner, Zeev; Arzy, Shahar

2018-05-21

This study aims to assess the role of mental-orientation in the diagnosis of mild cognitive impairment and Alzheimer's disease using a novel task. A behavioral study (Experiment 1) compared the mental-orientation task to standard neuropsychological tests in patients across the Alzheimer's disease spectrum. A functional MRI study (Experiment 2) in young adults compared activations evoked by the mental-orientation and standard-orientation tasks as well as their overlap with brain regions susceptible to Alzheimer's disease pathology. The mental-orientation task differentiated mild cognitively impaired and healthy controls at 95% accuracy, while the Addenbrooke's Cognitive Examination, Mini-Mental State Examination and standard-orientation achieved 74%, 70% and 50% accuracy, respectively. Functional MRI revealed the mental-orientation task to preferentially recruit brain regions exhibiting early Alzheimer's-related atrophy, unlike the standard-orientation test. Mental-orientation is suggested to play a key role in Alzheimer's disease, and consequently in early detection and follow-up of patients along the Alzheimer's disease spectrum. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Cognitive Flexibility in Drawings of Bilingual Children

ERIC Educational Resources Information Center

Adi-Japha, Esther; Berberich-Artzi, Jennie; Libnawi, Afaf

2010-01-01

A. Karmiloff-Smith's (1990) task of drawing a nonexistent object is considered to be a measure of cognitive flexibility. The notion of earlier emergence of cognitive flexibility in bilingual children motivated the current researchers to request 4- and 5-year-old English-Hebrew and Arabic-Hebrew bilingual children and their monolingual peers to…

Task switching costs in preschool children and adults.

PubMed

Peng, Anna; Kirkham, Natasha Z; Mareschal, Denis

2018-08-01

Past research investigating cognitive flexibility has shown that preschool children make many perseverative errors in tasks that require switching between different sets of rules. However, this inflexibility might not necessarily hold with easier tasks. The current study investigated the developmental differences in cognitive flexibility using a task-switching procedure that compared reaction times and accuracy in 4- and 6-year-olds with those in adults. The experiment involved simple target detection tasks and was intentionally designed in a way that the stimulus and response conflicts were minimal together with a long preparation window. Global mixing costs (performance costs when multiple tasks are relevant in a context), and local switch costs (performance costs due to switching to an alternative task) are typically thought to engage endogenous control processes. If this is the case, we should observe developmental differences with both of these costs. Our results show, however, that when the accuracy was good, there were no age differences in cognitive flexibility (i.e., the ability to manage multiple tasks and to switch between tasks) between children and adults. Even though preschool children had slower reaction times and were less accurate, the mixing and switch costs associated with task switching were not reliably larger for preschool children. Preschool children did, however, show more commission errors and greater response repetition effects than adults, which may reflect differences in inhibitory control. Copyright © 2018 Elsevier Inc. All rights reserved.

The equivalent internal orientation and position noise for contour integration.

PubMed

Baldwin, Alex S; Fu, Minnie; Farivar, Reza; Hess, Robert F

2017-10-12

Contour integration is the joining-up of local responses to parts of a contour into a continuous percept. In typical studies observers detect contours formed of discrete wavelets, presented against a background of random wavelets. This measures performance for detecting contours in the limiting external noise that background provides. Our novel task measures contour integration without requiring any background noise. This allowed us to perform noise-masking experiments using orientation and position noise. From these we measure the equivalent internal noise for contour integration. We found an orientation noise of 6° and position noise of 3 arcmin. Orientation noise was 2.6x higher in contour integration compared to an orientation discrimination control task. Comparing against a position discrimination task found position noise in contours to be 2.4x lower. This suggests contour integration involves intermediate processing that enhances the quality of element position representation at the expense of element orientation. Efficiency relative to the ideal observer was lower for the contour tasks (36% in orientation noise, 21% in position noise) compared to the controls (54% and 57%).

The paradox of cognitive flexibility in autism

PubMed Central

Geurts, Hilde M.; Corbett, Blythe; Solomon, Marjorie

2017-01-01

We present an overview of current literature addressing cognitive flexibility in autism spectrum disorders. Based on recent studies at multiple sites, using diverse methods and participants of different autism subtypes, ages and cognitive levels, no consistent evidence for cognitive flexibility deficits was found. Researchers and clinicians assume that inflexible everyday behaviors in autism are directly related to cognitive flexibility deficits as assessed by clinical and experimental measures. However, there is a large gap between the day-to-day behavioral flexibility and that measured with these cognitive flexibility tasks. To advance the field, experimental measures must evolve to reflect mechanistic models of flexibility deficits. Moreover, ecologically valid measures are required to be able to resolve the paradox between cognitive and behavioral inflexibility. PMID:19138551

Relationship among achievement goal orientations and multidimensional situational motivation in physical education.

PubMed

Standage, Martyn; Treasure, Darren C

2002-03-01

Contemporary research suggests that task and ego achievement goal orientations affect students' intrinsic motivation in physical education. This research has assessed intrinsic motivation as a unidimensional contruct, however, which is inconsistent with the more contemporary postulates of self-determination theory (Deci & Ryan, 1985, 1991) which states that intrinsic motivation is only one type of motivation. To date, research has not addressed whether different types of motivation at the situational level are influenced by the proneness to adopt task or ego involvement. To examine the relationship between achievement goal orientations and multidimensional situational motivation in PE. Middle school children (182 male, 136 female; M age = 13.2 years). Responded to questionnaires assessing their dispositional goal orientation (POSQ; Roberts, Treasure, & Balague, 1998) and situational motivation (SIMS; Guay, Vallerand, & Blanchard, 2000) in PE. Task orientation was found to be positively associated with more self-determined types of situational motivation. Ego orientation was weakly related to less self-determined motivation. An extreme group split was conducted to create four goal groups and goal profile analyses conducted. A significant MANOVA was followed by univariate analyses, post hoc comparisons, and calculated effect sizes, which revealed that groups high in task orientation reported more motivationally adaptive responses than groups low in task orientation. The results suggest that a high level of task orientation singularly or in combination with ego orientation fosters self-determined situational motivation in the context of PE.

Retention-Oriented Curricular Design

ERIC Educational Resources Information Center

Milanovic, Ivana; Eppes, Tom A.; Girouard, Janice; Townsend, Lee

2010-01-01

This paper presents a retention-oriented approach to the educational value stream within the STEM undergraduate area. Faced with several strategic challenges and opportunities, a Flex Advantage Plan was developed to enhance the undergraduate engineering technology programs and better utilize the curricular flexibilities inherent in the current…

System and method for seamless task-directed autonomy for robots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nielsen, Curtis; Bruemmer, David; Few, Douglas

Systems, methods, and user interfaces are used for controlling a robot. An environment map and a robot designator are presented to a user. The user may place, move, and modify task designators on the environment map. The task designators indicate a position in the environment map and indicate a task for the robot to achieve. A control intermediary links task designators with robot instructions issued to the robot. The control intermediary analyzes a relative position between the task designators and the robot. The control intermediary uses the analysis to determine a task-oriented autonomy level for the robot and communicates targetmore » achievement information to the robot. The target achievement information may include instructions for directly guiding the robot if the task-oriented autonomy level indicates low robot initiative and may include instructions for directing the robot to determine a robot plan for achieving the task if the task-oriented autonomy level indicates high robot initiative.« less

Effect of a Task-Oriented Rehabilitation Program on Upper Extremity Recovery Following Motor Stroke: The ICARE Randomized Clinical Trial.

PubMed

Winstein, Carolee J; Wolf, Steven L; Dromerick, Alexander W; Lane, Christianne J; Nelsen, Monica A; Lewthwaite, Rebecca; Cen, Steven Yong; Azen, Stanley P

2016-02-09

Clinical trials suggest that higher doses of task-oriented training are superior to current clinical practice for patients with stroke with upper extremity motor deficits. To compare the efficacy of a structured, task-oriented motor training program vs usual and customary occupational therapy (UCC) during stroke rehabilitation. Phase 3, pragmatic, single-blind randomized trial among 361 participants with moderate motor impairment recruited from 7 US hospitals over 44 months, treated in the outpatient setting from June 2009 to March 2014. Structured, task-oriented upper extremity training (Accelerated Skill Acquisition Program [ASAP]; n = 119); dose-equivalent occupational therapy (DEUCC; n = 120); or monitoring-only occupational therapy (UCC; n = 122). The DEUCC group was prescribed 30 one-hour sessions over 10 weeks; the UCC group was only monitored, without specification of dose. The primary outcome was 12-month change in log-transformed Wolf Motor Function Test time score (WMFT, consisting of a mean of 15 timed arm movements and hand dexterity tasks). Secondary outcomes were change in WMFT time score (minimal clinically important difference [MCID] = 19 seconds) and proportion of patients improving ≥25 points on the Stroke Impact Scale (SIS) hand function score (MCID = 17.8 points). Among the 361 randomized patients (mean age, 60.7 years; 56% men; 42% African American; mean time since stroke onset, 46 days), 304 (84%) completed the 12-month primary outcome assessment; in intention-to-treat analysis, mean group change scores (log WMFT, baseline to 12 months) were, for the ASAP group, 2.2 to 1.4 (difference, 0.82); DEUCC group, 2.0 to 1.2 (difference, 0.84); and UCC group, 2.1 to 1.4 (difference, 0.75), with no significant between-group differences (ASAP vs DEUCC: 0.14; 95% CI, -0.05 to 0.33; P = .16; ASAP vs UCC: -0.01; 95% CI, -0.22 to 0.21; P = .94; and DEUCC vs UCC: -0.14; 95% CI, -0.32 to 0.05; P = .15). Secondary outcomes for the ASAP

Attention orienting and inhibitory control across the different mood states in bipolar disorder: an emotional antisaccade task.

PubMed

García-Blanco, Ana C; Perea, Manuel; Salmerón, Ladislao

2013-12-01

An antisaccade experiment, using happy, sad, and neutral faces, was conducted to examine the effect of mood-congruent information on inhibitory control (antisaccade task) and attentional orienting (prosaccade task) during the different episodes of bipolar disorder (BD) - manic (n=22), depressive (n=25), and euthymic (n=24). A group of 28 healthy controls was also included. Results revealed that symptomatic patients committed more antisaccade errors than healthy individuals, especially with mood-congruent faces. The manic group committed more antisaccade errors in response to happy faces, while the depressed group tended to commit more antisaccade errors in response to sad faces. Additionally, antisaccade latencies were slower in BD patients than in healthy individuals, whereas prosaccade latencies were slower in symptomatic patients. Taken together, these findings revealed the following: (a) slow inhibitory control in BD patients, regardless of their episode (i.e., a trait), and (b) impaired inhibitory control restricted to symptomatic patients (i.e., a state). Copyright © 2013 Elsevier B.V. All rights reserved.

Relationships among goal orientations, motivational climate and flow in adolescent athletes: differences by gender.

PubMed

Moreno Murcia, Juan Antonio; Cervelló Gimeno, Eduardo; González-Cutre Coll, David

2008-05-01

The purpose of this investigation was to examine the relationships among perceived motivational climate, individuals' goal orientations, and dispositional flow, with attention to possible gender differences. A sample of 413 young athletes, ages 12 to 16 years, completed the Perceived Motivational Climate in Sport Questionnaire-2 (PMCSQ-2) and Perception of Success Questionnaire (POSQ), as well as the Dispositional Flow Scale. Task orientation was positively and significantly related to a perceived task-involving motivational climate and to the disposition to experience flow in the sport. Ego orientation was positively and significantly associated with a perceived ego-involving motivational climate and with dispositional flow. The perceptions of task-involving and ego-involving motivational climates were positively and significantly linked to general dispositional flow. Multiple regression analysis indicated that both task and ego goal orientations and perceived task- and ego-oriented climates predicted dispositional flow. Males displayed a stronger ego orientation, and were more likely to report that they participated in an ego-oriented climate, than did females. To the contrary, the females were more likely to perceive a task-oriented climate than did the males. No meaningful differences were found between males and females in general dispositional flow.

Mechanisms underlying flexible adaptation of cognitive control: behavioral and neuroimaging evidence in a flanker task.

PubMed

Zurawska Vel Grajewska, Blandyna; Sim, Eun-Jin; Hoenig, Klaus; Herrnberger, Bärbel; Kiefer, Markus

2011-11-03

Cognitive control can be adapted flexibly according to the conflict level in a given situation. In the Eriksen flanker task, interference evoked by flankers is larger in conditions with a higher, rather than a lower proportion of compatible trials. Such compatibility ratio effects also occur for stimuli presented at two spatial locations suggesting that different cognitive control settings can be simultaneously maintained. However, the conditions and the neural correlates of this flexible adaptation of cognitive control are only poorly understood. In the present study, we further elucidated the mechanisms underlying the simultaneous maintenance of two cognitive control settings. In behavioral experiments, stimuli were presented centrally above and below fixation and hence processed by both hemispheres or lateralized to stimulate hemispheres differentially. The different compatibility ratio at two stimulus locations had a differential influence on the flanker effect in both experiments. In an fMRI experiment, blocks with an identical compatibility ratio at two central spatial locations elicited stronger activity in a network of prefrontal and parietal brain areas, which are known to be involved in conflict resolution and cognitive control, as compared with blocks with a different compatibility ratio at the same spatial locations. This demonstrates that the simultaneous maintenance of two conflicting control settings vs. one single setting does not recruit additional neural circuits suggesting the involvement of one single cognitive control system. Instead a crosstalk between multiple control settings renders adaptation of cognitive control more efficient when only one uniform rather than two different control settings has to be simultaneously maintained. Copyright © 2011 Elsevier B.V. All rights reserved.

A Cross-Cultural Comparison of Children's Imitative Flexibility

ERIC Educational Resources Information Center

Clegg, Jennifer M.; Legare, Cristine H.

2016-01-01

Recent research with Western populations has demonstrated that children use imitation flexibly to engage in both instrumental and conventional learning. Evidence for children's imitative flexibility in non-Western populations is limited, however, and has only assessed imitation of instrumental tasks. This study (N = 142, 6- to 8-year-olds)…

One night of sleep loss impairs innovative thinking and flexible decision making.

PubMed

Harrison, Y; Horne, J A

1999-05-01

Recent findings with clinically oriented neuropsychological tests suggest that one night without sleep causes particular impairment to tasks requiring flexible thinking and the updating of plans in the light of new information. This relatively little investigated field of sleep deprivation research has real-world implications for decision makers having lost a night's sleep. To explore this latter perspective further, we adapted a dynamic and realistic marketing decision making "game" embodying the need for these skills, and whereby such performance could be measured. As the task relied on the comprehension of a large amount of written information, a critical reasoning test was also administered to ascertain whether any failure at the marketing game might lie with information acquisition rather than with failures in decision making. Ten healthy highly motivated and trained participants underwent two counterbalanced 36 h trials, sleep vs no sleep. The critical reasoning task was unaffected by sleep loss, whereas performance at the game significantly deteri orated after 32-36 h of sleep loss, when sleep deprivation led to more rigid thinking, increased perseverative errors, and marked difficulty in appreciating an updated situation. At this point, and despite the sleep-deprived participants' best efforts to do well, their play collapsed, unlike that of the nonsleep-deprived participants. Copyright 1999 Academic Press.

Object-oriented models of cognitive processing.

PubMed

Mather, G

2001-05-01

Information-processing models of vision and cognition are inspired by procedural programming languages. Models that emphasize object-based representations are closely related to object-oriented programming languages. The concepts underlying object-oriented languages provide a theoretical framework for cognitive processing that differs markedly from that offered by procedural languages. This framework is well-suited to a system designed to deal flexibly with discrete objects and unpredictable events in the world.

Test Plans. Lightweight Durable TPS: Tasks 1,2,4,5, and 6

NASA Technical Reports Server (NTRS)

Greenberg, H. S.; Tu, Tina

1994-01-01

The objective of this task is to develop the fluted core flexible blankets, also referred to as the Tailorable Advanced Blanket Insulation (TABI), to a technology readiness level (TRL) of 6. This task is one of the six tasks under TA 3, Lightweight Durable TPS study, of the Single Stage to Orbit (SSTO) program. The purpose of this task is to develop a durable and low maintenance flexible TPS blanket material to be implemented on the SSTO vehicle.

Effects of orientation on Rey complex figure performance.

PubMed

Ferraro, F Richard; Grossman, Jennifer; Bren, Amy; Hoverson, Allysa

2002-10-01

An experiment was performed that examined the impact of stimulus orientation on performance on the Rey complex figure. A total of 48 undergraduates (24 men, 24 women) were randomly assigned to one of four Rey figure orientation groups (0 degrees, 90 degrees, 180 degrees, and 270 degrees ). Participants followed standard procedures for the Rey figure, initially copying it in whatever orientation group they were assigned to. Next, all participants performed a 15-20 min lexical decision experiment, used as a filler task. Finally, and unbeknownest to them, participants were asked to recall as much of the figure as they could. As expected, results revealed a main effect of Task (F = 83.92, p < .01), in which copy performance was superior to recall performance. However, the main effect for orientation was not significant, nor did orientation interact with task (Fs < .68, ps > .57). The results are important from an applied setting, especially if testing conditions are less than optimal and a fixed stimulus position is not possible (e.g., testing at the bedside).

The Degree of Early Life Stress Predicts Decreased Medial Prefrontal Activations and the Shift from Internally to Externally Guided Decision Making: An Exploratory NIRS Study during Resting State and Self-Oriented Task

PubMed Central

Nakao, Takashi; Matsumoto, Tomoya; Morita, Machiko; Shimizu, Daisuke; Yoshimura, Shinpei; Northoff, Georg; Morinobu, Shigeru; Okamoto, Yasumasa; Yamawaki, Shigeto

2013-01-01

Early life stress (ELS), an important risk factor for psychopathology in mental disorders, is associated neuronally with decreased functional connectivity within the default mode network (DMN) in the resting state. Moreover, it is linked with greater deactivation in DMN during a working memory task. Although DMN shows large amplitudes of very low-frequency oscillations (VLFO) and strong involvement during self-oriented tasks, these features’ relation to ELS remains unclear. Therefore, our preliminary study investigated the relationship between ELS and the degree of frontal activations during a resting state and self-oriented task using near-infrared spectroscopy (NIRS). From 22 healthy participants, regional hemodynamic changes in 43 front-temporal channels were recorded during 5 min resting states, and execution of a self-oriented task (color-preference judgment) and a control task (color-similarity judgment). Using a child abuse and trauma scale, ELS was quantified. We observed that ELS showed a negative correlation with medial prefrontal cortex (MPFC) activation during both resting state and color-preference judgment. In contrast, no significant correlation was found between ELS and MPFC activation during color-similarity judgment. Additionally, we observed that ELS and the MPFC activation during color-preference judgment were associated behaviorally with the rate of similar color choice in preference judgment, which suggests that, for participants with higher ELS, decisions in the color-preference judgment were based on an external criterion (color similarity) rather than an internal criterion (subjective preference). Taken together, our neuronal and behavioral findings show that high ELS is related to lower MPFC activation during both rest and self-oriented tasks. This is behaviorally manifest in an abnormal shift from internally to externally guided decision making, even under circumstances where internal guidance is required. PMID:23840186

Flexible statistical modelling detects clinical functional magnetic resonance imaging activation in partially compliant subjects.

PubMed

Waites, Anthony B; Mannfolk, Peter; Shaw, Marnie E; Olsrud, Johan; Jackson, Graeme D

2007-02-01

Clinical functional magnetic resonance imaging (fMRI) occasionally fails to detect significant activation, often due to variability in task performance. The present study seeks to test whether a more flexible statistical analysis can better detect activation, by accounting for variance associated with variable compliance to the task over time. Experimental results and simulated data both confirm that even at 80% compliance to the task, such a flexible model outperforms standard statistical analysis when assessed using the extent of activation (experimental data), goodness of fit (experimental data), and area under the operator characteristic curve (simulated data). Furthermore, retrospective examination of 14 clinical fMRI examinations reveals that in patients where the standard statistical approach yields activation, there is a measurable gain in model performance in adopting the flexible statistical model, with little or no penalty in lost sensitivity. This indicates that a flexible model should be considered, particularly for clinical patients who may have difficulty complying fully with the study task.

The role of verbal labels on flexible memory retrieval at 12-months of age.

PubMed

Taylor, Gemma; Liu, Hao; Herbert, Jane S

2016-11-01

The provision of verbal labels enhances 12-month-old infants' memory flexibility across a form change in a puppet imitation task (Herbert, 2011), although the mechanisms for this effect remain unclear. Here we investigate whether verbal labels can scaffold flexible memory retrieval when task difficulty increases and consider the mechanism responsible for the effect of language cues on early memory flexibility. Twelve-month-old infants were provided with English, Chinese, or empty language cues during a difficult imitation task, a combined change in the puppet's colour and form at the test (Hayne et al., 1997). Imitation performance by infants in the English language condition only exceeded baseline performance after the 10-min delay. Thus, verbal labels facilitated flexible memory retrieval on this task. There were no correlations between infants' language comprehension and imitation performance. Thus, it is likely that verbal labels facilitate both attention and categorisation during encoding and retrieval. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Transfer of perceptual learning between different visual tasks

PubMed Central

McGovern, David P.; Webb, Ben S.; Peirce, Jonathan W.

2012-01-01

Practice in most sensory tasks substantially improves perceptual performance. A hallmark of this ‘perceptual learning' is its specificity for the basic attributes of the trained stimulus and task. Recent studies have challenged the specificity of learned improvements, although transfer between substantially different tasks has yet to be demonstrated. Here, we measure the degree of transfer between three distinct perceptual tasks. Participants trained on an orientation discrimination, a curvature discrimination, or a ‘global form' task, all using stimuli comprised of multiple oriented elements. Before and after training they were tested on all three and a contrast discrimination control task. A clear transfer of learning was observed, in a pattern predicted by the relative complexity of the stimuli in the training and test tasks. Our results suggest that sensory improvements derived from perceptual learning can transfer between very different visual tasks. PMID:23048211

Transfer of perceptual learning between different visual tasks.

PubMed

McGovern, David P; Webb, Ben S; Peirce, Jonathan W

2012-10-09

Practice in most sensory tasks substantially improves perceptual performance. A hallmark of this 'perceptual learning' is its specificity for the basic attributes of the trained stimulus and task. Recent studies have challenged the specificity of learned improvements, although transfer between substantially different tasks has yet to be demonstrated. Here, we measure the degree of transfer between three distinct perceptual tasks. Participants trained on an orientation discrimination, a curvature discrimination, or a 'global form' task, all using stimuli comprised of multiple oriented elements. Before and after training they were tested on all three and a contrast discrimination control task. A clear transfer of learning was observed, in a pattern predicted by the relative complexity of the stimuli in the training and test tasks. Our results suggest that sensory improvements derived from perceptual learning can transfer between very different visual tasks.

Flexible automation of cell culture and tissue engineering tasks.

PubMed

Knoll, Alois; Scherer, Torsten; Poggendorf, Iris; Lütkemeyer, Dirk; Lehmann, Jürgen

2004-01-01

Until now, the predominant use cases of industrial robots have been routine handling tasks in the automotive industry. In biotechnology and tissue engineering, in contrast, only very few tasks have been automated with robots. New developments in robot platform and robot sensor technology, however, make it possible to automate plants that largely depend on human interaction with the production process, e.g., for material and cell culture fluid handling, transportation, operation of equipment, and maintenance. In this paper we present a robot system that lends itself to automating routine tasks in biotechnology but also has the potential to automate other production facilities that are similar in process structure. After motivating the design goals, we describe the system and its operation, illustrate sample runs, and give an assessment of the advantages. We conclude this paper by giving an outlook on possible further developments.

Effects of Causal Attributions Following Mathematics Tasks on Student Cognitions about a Subsequent Task

ERIC Educational Resources Information Center

Seegers, Gerard; Van Putten, Cornelis M.; Vermeer, Harriet J.

2004-01-01

The authors investigated the effects of former learning experiences on how students adapt to challenging mathematics tasks. A distinction has been made between domain-specific variables (goal orientation, self-concept of mathematics ability) and task- (or context-) specific appraisals (estimated competence for, attractiveness and relevance of the…

Differential effects of social and novelty enrichment on individual differences in impulsivity and behavioral flexibility

PubMed Central

Wang, Maya Zhe; Marshall, Andrew T.; Kirkpatrick, Kimberly

2017-01-01

Early life experience profoundly impacts behavior and cognitive functions in rats. The present study investigated how the presence of conspecifics and/or novel objects, could independently influence individual differences in impulsivity and behavioral flexibility. Twenty-four rats were reared in an isolated condition, an isolated condition with a novel object, a pair-housed social condition, or a pair-housed social condition with a novel object. The rats were then tested on an impulsive choice task, a behavioral flexibility task, and an impulsive action task. Novelty enrichment produced an overall increase in impulsive choice, while social enrichment decreased impulsive choice in the absence of novelty enrichment and also produced an overall increase in impulsive action. In the behavioral flexibility task, social enrichment increased regressive errors, whereas both social and novelty enrichment reduced never reinforced errors. Individual differences analyses indicated a significant relationship between performance in the behavioral flexibility and impulsive action tasks, which may reflect a common psychological correlate of action inhibition. Moreover, there was a relationship between delay sensitivity in the impulsive choice task and performance on the DRL and behavioral flexibility tasks, suggesting a dual role for timing and inhibitory processes in driving the interrelationship between these tasks. Overall, these results indicate that social and novelty enrichment produce distinct effects on impulsivity and adaptability, suggesting the need to parse out the different elements of enrichment in future studies. Further research is warranted to better understand how individual differences in sensitivity to enrichment affect individuals’ interactions with and the resulting consequences of the rearing environment. PMID:28341610

The relation of saturated fats and dietary cholesterol to childhood cognitive flexibility.

PubMed

Khan, Naiman A; Raine, Lauren B; Drollette, Eric S; Scudder, Mark R; Hillman, Charles H

2015-10-01

Identification of health behaviors and markers of physiological health associated with childhood cognitive function has important implications for public health policy targeted toward cognitive health throughout the life span. Although previous studies have shown that aerobic fitness and obesity exert contrasting effects on cognitive flexibility among prepubertal children, the extent to which diet plays a role in cognitive flexibility has received little attention. Accordingly, this study examined associations between saturated fats and cholesterol intake and cognitive flexibility, assessed using a task switching paradigm, among prepubertal children between 7 and 10 years (N = 150). Following adjustment of confounding variables (age, sex, socioeconomic status, IQ, VO2max, and BMI), children consuming diets higher in saturated fats exhibited longer reaction time during the task condition requiring greater amounts of cognitive flexibility. Further, increasing saturated fat intake and dietary cholesterol were correlated with greater switch costs, reflecting impaired ability to maintain multiple task sets in working memory and poorer efficiency of cognitive control processes involved in task switching. These data are among the first to indicate that children consuming diets higher in saturated fats and cholesterol exhibit compromised ability to flexibly modulate their cognitive operations, particularly when faced with greater cognitive challenge. Future longitudinal and intervention studies are necessary to comprehensively characterize the interrelationships between diet, aerobic fitness, obesity, and children's cognitive abilities. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of tool handle dimension and workpiece orientation and size on wrist ulnar/radial torque strength, usability and discomfort in a wrench task.

PubMed

Dianat, Iman; Rahimi, Soleyman; Nedaei, Moein; Asghari Jafarabadi, Mohammad; Oskouei, Ali E

2017-03-01

The effects of tool handle dimension (three modified designs of wrenches with 30-50 mm diameter cylindrical handles and traditional design with rectangular cross-sectional (5 mm × 25 mm) handle), workpiece orientation (vertical/horizontal) and workpiece size (small/large) as well as user's hand size on wrist ulnar/radial (U/R) torque strength, usability and discomfort, and also the relationship between these variables were evaluated in a maximum torque task using wrenches. The highest and lowest levels of maximal wrist U/R torque strength were recorded for the 30 mm diameter handle and traditional wrench design, respectively. The prototype handle with 30 mm diameter, together with 40 mm diameter handle, was also better than other designs as they received higher usability ratings and caused less discomfort. The mean wrist torque strength exerted on a vertically oriented workpiece (in the sagittal plane) was 23.8% higher than that exerted on a horizontally oriented one (in the transverse plane). The user's hand size had no effect on torque exertions. The wrist torque strength and usability were negatively correlated with hand and finger discomfort ratings. The results are also discussed in terms of their implications for hand tool and workstation configuration in torque tasks involving wrenches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Flexible Coding of Visual Working Memory Representations during Distraction.

PubMed

Lorenc, Elizabeth S; Sreenivasan, Kartik K; Nee, Derek E; Vandenbroucke, Annelinde R E; D'Esposito, Mark

2018-06-06

Visual working memory (VWM) recruits a broad network of brain regions, including prefrontal, parietal, and visual cortices. Recent evidence supports a "sensory recruitment" model of VWM, whereby precise visual details are maintained in the same stimulus-selective regions responsible for perception. A key question in evaluating the sensory recruitment model is how VWM representations persist through distracting visual input, given that the early visual areas that putatively represent VWM content are susceptible to interference from visual stimulation.To address this question, we used a functional magnetic resonance imaging inverted encoding model approach to quantitatively assess the effect of distractors on VWM representations in early visual cortex and the intraparietal sulcus (IPS), another region previously implicated in the storage of VWM information. This approach allowed us to reconstruct VWM representations for orientation, both before and after visual interference, and to examine whether oriented distractors systematically biased these representations. In our human participants (both male and female), we found that orientation information was maintained simultaneously in early visual areas and IPS in anticipation of possible distraction, and these representations persisted in the absence of distraction. Importantly, early visual representations were susceptible to interference; VWM orientations reconstructed from visual cortex were significantly biased toward distractors, corresponding to a small attractive bias in behavior. In contrast, IPS representations did not show such a bias. These results provide quantitative insight into the effect of interference on VWM representations, and they suggest a dynamic tradeoff between visual and parietal regions that allows flexible adaptation to task demands in service of VWM. SIGNIFICANCE STATEMENT Despite considerable evidence that stimulus-selective visual regions maintain precise visual information in working

Synthetic Synchronisation: From Attention and Multi-Tasking to Negative Capability and Judgment

ERIC Educational Resources Information Center

Stables, Andrew

2013-01-01

Educational literature has tended to focus, explicitly and implicitly, on two kinds of task orientation: the ability either to focus on a single task, or to multi-task. A third form of orientation characterises many highly successful people. This is the ability to combine several tasks into one: to "kill two (or more) birds with one…

On the Flexibility of Basic Risk Attitudes in Monkeys.

PubMed

Farashahi, Shiva; Azab, Habiba; Hayden, Benjamin; Soltani, Alireza

2018-05-02

Monkeys and other animals appear to share with humans two risk attitudes predicted by prospect theory: an inverse-S-shaped probability-weighting (PW) function and a steeper utility curve for losses than for gains. These findings suggest that such preferences are stable traits with common neural substrates. We hypothesized instead that animals tailor their preferences to subtle changes in task contexts, making risk attitudes flexible. Previous studies used a limited number of outcomes, trial types, and contexts. To gain a broader perspective, we examined two large datasets of male macaques' risky choices: one from a task with real (juice) gains and another from a token task with gains and losses. In contrast to previous findings, monkeys were risk seeking for both gains and losses (i.e., lacked a reflection effect) and showed steeper gain than loss curves (loss seeking). Utility curves for gains were substantially different in the two tasks. Monkeys showed nearly linear PWs in one task and S-shaped ones in the other; neither task produced a consistent inverse-S-shaped curve. To account for these observations, we developed and tested various computational models of the processes involved in the construction of reward value. We found that adaptive differential weighting of prospective gamble outcomes could partially account for the observed differences in the utility functions across the two experiments and thus provide a plausible mechanism underlying flexible risk attitudes. Together, our results support the idea that risky choices are constructed flexibly at the time of elicitation and place important constraints on neural models of economic choice. SIGNIFICANCE STATEMENT We respond in reliable ways to risk, but are our risk preferences stable traits or ephemeral states? Using various computational models, we examined two large datasets of macaque risky choices in two different tasks. We observed several deviations from "classic" risk preferences seen in humans and

Taking Aim at the Cognitive Side of Learning in Sensorimotor Adaptation Tasks.

PubMed

McDougle, Samuel D; Ivry, Richard B; Taylor, Jordan A

2016-07-01

Sensorimotor adaptation tasks have been used to characterize processes responsible for calibrating the mapping between desired outcomes and motor commands. Research has focused on how this form of error-based learning takes place in an implicit and automatic manner. However, recent work has revealed the operation of multiple learning processes, even in this simple form of learning. This review focuses on the contribution of cognitive strategies and heuristics to sensorimotor learning, and how these processes enable humans to rapidly explore and evaluate novel solutions to enable flexible, goal-oriented behavior. This new work points to limitations in current computational models, and how these must be updated to describe the conjoint impact of multiple processes in sensorimotor learning. Copyright © 2016 Elsevier Ltd. All rights reserved.

Concentration of Swiss Elite Orienteers.

ERIC Educational Resources Information Center

Seiler, Roland; Wetzel, Jorg

1997-01-01

A visual discrimination task was used to measure concentration among 43 members of Swiss national orienteering teams. Subjects were above average in the number of target objects dealt with and in duration of continuous concentration. For females only, ranking in orienteering performance was related to quality of concentration (ratio of correct to…

Sex differences in a landmark environmental re-orientation task only during the learning phase.

PubMed

Piccardi, Laura; Bianchini, Filippo; Iasevoli, Luigi; Giannone, Gianluca; Guariglia, Cecilia

2011-10-10

Sex differences are consistently reported in human navigation. Indeed, to orient themselves during navigation women are more likely to use landmark-based strategies and men Euclidean-based strategies. The difference could be due to selective social pressure, which fosters greater spatial ability in men, or biological factors. And the great variability of the results reported in the literature could be due to the experimental setting more than real differences in ability. In this study, navigational behaviour was assessed by means of a place-learning task in which a modified version of the Morris water maze for humans was used to evaluate sex differences. In using landmarks, sex differences emerged only during the learning phase. Although the men were faster than the women in locating the target position, the differences between the sexes disappeared in delayed recall. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Working memory load affects repetitive behaviour but not cognitive flexibility in adolescent autism spectrum disorder.

PubMed

Wolff, Nicole; Chmielewski, Witold X; Beste, Christian; Roessner, Veit

2017-03-16

Autism spectrum disorder (ASD) is associated with repetitive and stereotyped behaviour, suggesting that cognitive flexibility may be deficient in ASD. A central, yet not examined aspect to understand possible deficits in flexible behaviour in ASD relates (i) to the role of working memory and (ii) to neurophysiological mechanisms underlying behavioural modulations. We analysed behavioural and neurophysiological (EEG) correlates of cognitive flexibility using a task-switching paradigm with and without working memory load in adolescents with ASD and typically developing controls (TD). Adolescents with ASD versus TD show similar performance in task switching with no memory load, indicating that 'pure' cognitive flexibility is not in deficit in adolescent ASD. However performance during task repetition decreases with increasing memory load. Neurophysiological data reflect the pattern of behavioural effects, showing modulations in P2 and P3 event-related potentials. Working memory demands affect repetitive behaviour while processes of cognitive flexibility are unaffected. Effects emerge due to deficits in preparatory attentional processes and deficits in task rule activation, organisation and implementation of task sets when repetitive behaviour is concerned. It may be speculated that the habitual response mode in ASD (i.e. repetitive behaviour) is particularly vulnerable to additional demands on executive control processes.

Tapping Into Rate Flexibility: Musical Training Facilitates Synchronization Around Spontaneous Production Rates

PubMed Central

Scheurich, Rebecca; Zamm, Anna; Palmer, Caroline

2018-01-01

The ability to flexibly adapt one’s behavior is critical for social tasks such as speech and music performance, in which individuals must coordinate the timing of their actions with others. Natural movement frequencies, also called spontaneous rates, constrain synchronization accuracy between partners during duet music performance, whereas musical training enhances synchronization accuracy. We investigated the combined influences of these factors on the flexibility with which individuals can synchronize their actions with sequences at different rates. First, we developed a novel musical task capable of measuring spontaneous rates in both musicians and non-musicians in which participants tapped the rhythm of a familiar melody while hearing the corresponding melody tones. The novel task was validated by similar measures of spontaneous rates generated by piano performance and by the tapping task from the same pianists. We then implemented the novel task with musicians and non-musicians as they synchronized tapping of a familiar melody with a metronome at their spontaneous rates, and at rates proportionally slower and faster than their spontaneous rates. Musicians synchronized more flexibly across rates than non-musicians, indicated by greater synchronization accuracy. Additionally, musicians showed greater engagement of error correction mechanisms than non-musicians. Finally, differences in flexibility were characterized by more recurrent (repetitive) and patterned synchronization in non-musicians, indicative of greater temporal rigidity. PMID:29681872

Psychophysiological responses of junior orienteers under competitive pressure.

PubMed

Robazza, Claudio; Izzicupo, Pascal; D'Amico, Maria Angela; Ghinassi, Barbara; Crippa, Maria Chiara; Di Cecco, Vincenzo; Ruiz, Montse C; Bortoli, Laura; Di Baldassarre, Angela

2018-01-01

The purpose of the study was to examine psychobiosocial states, cognitive functions, endocrine responses (i.e., salivary cortisol and chromogranin A), and performance under competitive pressure in orienteering athletes. The study was grounded in the individual zones of optimal functioning (IZOF) and biopsychosocial models. Fourteen junior orienteering athletes (7 girls and 7 boys), ranging in age from 15 to 20 years (M = 16.93, SD = 1.77) took part in a two-day competitive event. To enhance competitive pressure, emphasis was placed on the importance of the competition and race outcome. Psychophysiological and performance data were collected at several points before, during, and after the races. Results showed that an increase in cortisol levels was associated with competitive pressure and reflected in higher perceived exertion (day 1, r = .32; day 2, r = .46), higher intensity of dysfunctional states (day 1, r = .59; day 2, r = .55), lower intensity of functional states (day 1, r = -.36; day 2, r = -.33), and decay in memory (day 1, r = -.27; day 2, r = -.35), visual attention (day 1, r = -.56; day 2, r = -.35), and attention/mental flexibility (day 1, r = .16; day 2, r = .26) tasks. The second day we observed better performance times, lower intensity of dysfunctional states, lower cortisol levels, improved visual attention and attention/mental flexibility (p < .050). Across the two competition days, chromogranin A levels were higher (p < .050) on the most difficult loops of the race in terms of both physical and psychological demands. Findings suggest emotional, cognitive, psychophysiological, and performance variables to be related and to jointly change across different levels of cognitive and physical load. Overall results are discussed in light of the IZOF and biopsychosocial models. The procedure adopted in the study also supports the feasibility of including additional cognitive load for possible practical applications.

Psychophysiological responses of junior orienteers under competitive pressure

PubMed Central

Izzicupo, Pascal; D’Amico, Maria Angela; Ghinassi, Barbara; Crippa, Maria Chiara; Di Cecco, Vincenzo; Ruiz, Montse C.; Bortoli, Laura; Di Baldassarre, Angela

2018-01-01

The purpose of the study was to examine psychobiosocial states, cognitive functions, endocrine responses (i.e., salivary cortisol and chromogranin A), and performance under competitive pressure in orienteering athletes. The study was grounded in the individual zones of optimal functioning (IZOF) and biopsychosocial models. Fourteen junior orienteering athletes (7 girls and 7 boys), ranging in age from 15 to 20 years (M = 16.93, SD = 1.77) took part in a two-day competitive event. To enhance competitive pressure, emphasis was placed on the importance of the competition and race outcome. Psychophysiological and performance data were collected at several points before, during, and after the races. Results showed that an increase in cortisol levels was associated with competitive pressure and reflected in higher perceived exertion (day 1, r = .32; day 2, r = .46), higher intensity of dysfunctional states (day 1, r = .59; day 2, r = .55), lower intensity of functional states (day 1, r = -.36; day 2, r = -.33), and decay in memory (day 1, r = -.27; day 2, r = -.35), visual attention (day 1, r = -.56; day 2, r = -.35), and attention/mental flexibility (day 1, r = .16; day 2, r = .26) tasks. The second day we observed better performance times, lower intensity of dysfunctional states, lower cortisol levels, improved visual attention and attention/mental flexibility (p < .050). Across the two competition days, chromogranin A levels were higher (p < .050) on the most difficult loops of the race in terms of both physical and psychological demands. Findings suggest emotional, cognitive, psychophysiological, and performance variables to be related and to jointly change across different levels of cognitive and physical load. Overall results are discussed in light of the IZOF and biopsychosocial models. The procedure adopted in the study also supports the feasibility of including additional cognitive load for possible practical applications. PMID:29698498

Endogenous orienting in the archer fish.

PubMed

Saban, William; Sekely, Liora; Klein, Raymond M; Gabay, Shai

2017-07-18

The literature has long emphasized the neocortex's role in volitional processes. In this work, we examined endogenous orienting in an evolutionarily older species, the archer fish, which lacks neocortex-like cells. We used Posner's classic endogenous cuing task, in which a centrally presented, spatially informative cue is followed by a target. The fish responded to the target by shooting a stream of water at it. Interestingly, the fish demonstrated a human-like "volitional" facilitation effect: their reaction times to targets that appeared on the side indicated by the precue were faster than their reaction times to targets on the opposite side. The fish also exhibited inhibition of return, an aftermath of orienting that commonly emerges only in reflexive orienting tasks in human participants. We believe that this pattern demonstrates the acquisition of an arbitrary connection between spatial orienting and a nonspatial feature of a centrally presented stimulus in nonprimate species. In the literature on human attention, orienting in response to such contingencies has been strongly associated with volitional control. We discuss the implications of these results for the evolution of orienting, and for the study of volitional processes in all species, including humans.

Endogenous orienting in the archer fish

PubMed Central

Sekely, Liora; Klein, Raymond M.; Gabay, Shai

2017-01-01

The literature has long emphasized the neocortex’s role in volitional processes. In this work, we examined endogenous orienting in an evolutionarily older species, the archer fish, which lacks neocortex-like cells. We used Posner’s classic endogenous cuing task, in which a centrally presented, spatially informative cue is followed by a target. The fish responded to the target by shooting a stream of water at it. Interestingly, the fish demonstrated a human-like “volitional” facilitation effect: their reaction times to targets that appeared on the side indicated by the precue were faster than their reaction times to targets on the opposite side. The fish also exhibited inhibition of return, an aftermath of orienting that commonly emerges only in reflexive orienting tasks in human participants. We believe that this pattern demonstrates the acquisition of an arbitrary connection between spatial orienting and a nonspatial feature of a centrally presented stimulus in nonprimate species. In the literature on human attention, orienting in response to such contingencies has been strongly associated with volitional control. We discuss the implications of these results for the evolution of orienting, and for the study of volitional processes in all species, including humans. PMID:28673997

Switching between Tasks and Responses: A Developmental Study

ERIC Educational Resources Information Center

Crone, Eveline A.; Bunge, Silvia A.; van der Molen, Maurits W.; Ridderinkhof, K. Richard

2006-01-01

Task switching requires the ability to flexibly switch between task rules and responses, and is sensitive to developmental change. We tested the hypothesis that developmental changes in task switch performance are associated with changes in the facilitating or interfering effect of the previously retrieved stimulus-response (S-R) association.…

A Chaotic Particle Swarm Optimization-Based Heuristic for Market-Oriented Task-Level Scheduling in Cloud Workflow Systems.

PubMed

Li, Xuejun; Xu, Jia; Yang, Yun

2015-01-01

Cloud workflow system is a kind of platform service based on cloud computing. It facilitates the automation of workflow applications. Between cloud workflow system and its counterparts, market-oriented business model is one of the most prominent factors. The optimization of task-level scheduling in cloud workflow system is a hot topic. As the scheduling is a NP problem, Ant Colony Optimization (ACO) and Particle Swarm Optimization (PSO) have been proposed to optimize the cost. However, they have the characteristic of premature convergence in optimization process and therefore cannot effectively reduce the cost. To solve these problems, Chaotic Particle Swarm Optimization (CPSO) algorithm with chaotic sequence and adaptive inertia weight factor is applied to present the task-level scheduling. Chaotic sequence with high randomness improves the diversity of solutions, and its regularity assures a good global convergence. Adaptive inertia weight factor depends on the estimate value of cost. It makes the scheduling avoid premature convergence by properly balancing between global and local exploration. The experimental simulation shows that the cost obtained by our scheduling is always lower than the other two representative counterparts.

Demand-driven biogas production by flexible feeding in full-scale - Process stability and flexibility potentials.

PubMed

Mauky, Eric; Weinrich, Sören; Jacobi, Hans-Fabian; Nägele, Hans-Joachim; Liebetrau, Jan; Nelles, Michael

2017-08-01

For future energy supply systems with high proportions from renewable energy sources, biogas plants are a promising option to supply demand-driven electricity to compensate the divergence between energy demand and energy supply by uncontrolled sources like wind and solar. Apart expanding gas storage capacity a demand-oriented feeding with the aim of flexible gas production can be an effective alternative. The presented study demonstrated a high degree of intraday flexibility (up to 50% compared to the average) and a potential for an electricity shutdown of up to 3 days (decreasing gas production by more than 60%) by flexible feeding in full-scale. Furthermore, the long-term process stability was not affected negatively due to the flexible feeding. The flexible feeding resulted in a variable rate of gas production and a dynamic progression of individual acids and the respective pH-value. In consequence, a demand-driven biogas production may enable significant savings in terms of the required gas storage volume (up to 65%) and permit far greater plant flexibility compared to constant gas production. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Demystifying cognitive flexibility: Implications for clinical and developmental neuroscience

PubMed Central

Dajani, Dina R.; Uddin, Lucina Q.

2015-01-01

Cognitive flexibility, the readiness with which one can selectively switch between mental processes to generate appropriate behavioral responses, develops in a protracted manner and is compromised in several prevalent neurodevelopmental disorders. It is unclear whether cognitive flexibility arises from neural substrates distinct from the executive control network, or from the interplay of nodes within this and other networks. Here we review neuroimaging studies of cognitive flexibility, focusing on set shifting and task switching. We propose that more consistent operationalization and study of cognitive flexibility is required in clinical and developmental neuroscience. We suggest that an important avenue for future research is the characterization of the relationship between neural flexibility and cognitive flexibility in typical and atypical development. PMID:26343956

The scaling behavior of hand motions reveals self-organization during an executive function task

NASA Astrophysics Data System (ADS)

Anastas, Jason R.; Stephen, Damian G.; Dixon, James A.

2011-05-01

Recent approaches to cognition explain cognitive phenomena in terms of interaction-dominant dynamics. In the current experiment, we extend this approach to executive function, a construct used to describe flexible, goal-oriented behavior. Participants were asked to perform a widely used executive function task, card sorting, under two conditions. In one condition, participants were given a rule with which to sort the cards. In the other condition, participants had to induce the rule from experimenter feedback. The motion of each participant’s hand was tracked during the sorting task. Detrended fluctuation analysis was performed on the inter-point time series using a windowing strategy to capture changes over each trial. For participants in the induction condition, the Hurst exponent sharply increased and then decreased. The Hurst exponents for the explicit condition did not show this pattern. Our results suggest that executive function may be understood in terms of changes in stability that arise from interaction-dominant dynamics.

Differential effects of social and novelty enrichment on individual differences in impulsivity and behavioral flexibility.

PubMed

Wang, Maya Zhe; Marshall, Andrew T; Kirkpatrick, Kimberly

2017-06-01

Early life experience profoundly impacts behavior and cognitive functions in rats. The present study investigated how the presence of conspecifics and/or novel objects, could independently influence individual differences in impulsivity and behavioral flexibility. Twenty-four rats were reared in an isolated condition, an isolated condition with a novel object, a pair-housed social condition, or a pair-housed social condition with a novel object. The rats were then tested on an impulsive choice task, a behavioral flexibility task, and an impulsive action task. Novelty enrichment produced an overall increase in impulsive choice, while social enrichment decreased impulsive choice in the absence of novelty enrichment and also produced an overall increase in impulsive action. In the behavioral flexibility task, social enrichment increased regressive errors, whereas both social and novelty enrichment reduced never-reinforced errors. Individual differences analyses indicated a significant relationship between performance in the behavioral flexibility and impulsive action tasks, which may reflect a common psychological correlate of action inhibition. Moreover, there was a relationship between delay sensitivity in the impulsive choice task and performance on the DRL and behavioral flexibility tasks, suggesting a dual role for timing and inhibitory processes in driving the interrelationship between these tasks. Overall, these results indicate that social and novelty enrichment produce distinct effects on impulsivity and adaptability, suggesting the need to parse out the different elements of enrichment in future studies. Further research is warranted to better understand how individual differences in sensitivity to enrichment affect individuals' interactions with and the resulting consequences of the rearing environment. Copyright © 2017 Elsevier B.V. All rights reserved.

Linking Task Analysis with Student Learning.

ERIC Educational Resources Information Center

Sherman, Thomas M.; Wildman, Terry M.

An examination of task analysis from several perspectives in order to identify some of its purposes and advantages reveals that, as the interest in learning theory has shifted from a predominately behavioral perspective to a more cognitive orientation, the purpose of task analysis has also shifted. Formerly the purpose of task analysis was to aid…

Attention improves encoding of task-relevant features in the human visual cortex

PubMed Central

Jehee, Janneke F.M.; Brady, Devin K.; Tong, Frank

2011-01-01

When spatial attention is directed towards a particular stimulus, increased activity is commonly observed in corresponding locations of the visual cortex. Does this attentional increase in activity indicate improved processing of all features contained within the attended stimulus, or might spatial attention selectively enhance the features relevant to the observer’s task? We used fMRI decoding methods to measure the strength of orientation-selective activity patterns in the human visual cortex while subjects performed either an orientation or contrast discrimination task, involving one of two laterally presented gratings. Greater overall BOLD activation with spatial attention was observed in areas V1-V4 for both tasks. However, multivariate pattern analysis revealed that orientation-selective responses were enhanced by attention only when orientation was the task-relevant feature, and not when the grating’s contrast had to be attended. In a second experiment, observers discriminated the orientation or color of a specific lateral grating. Here, orientation-selective responses were enhanced in both tasks but color-selective responses were enhanced only when color was task-relevant. In both experiments, task-specific enhancement of feature-selective activity was not confined to the attended stimulus location, but instead spread to other locations in the visual field, suggesting the concurrent involvement of a global feature-based attentional mechanism. These results suggest that attention can be remarkably selective in its ability to enhance particular task-relevant features, and further reveal that increases in overall BOLD amplitude are not necessarily accompanied by improved processing of stimulus information. PMID:21632942

Attention improves encoding of task-relevant features in the human visual cortex.

PubMed

Jehee, Janneke F M; Brady, Devin K; Tong, Frank

2011-06-01

When spatial attention is directed toward a particular stimulus, increased activity is commonly observed in corresponding locations of the visual cortex. Does this attentional increase in activity indicate improved processing of all features contained within the attended stimulus, or might spatial attention selectively enhance the features relevant to the observer's task? We used fMRI decoding methods to measure the strength of orientation-selective activity patterns in the human visual cortex while subjects performed either an orientation or contrast discrimination task, involving one of two laterally presented gratings. Greater overall BOLD activation with spatial attention was observed in visual cortical areas V1-V4 for both tasks. However, multivariate pattern analysis revealed that orientation-selective responses were enhanced by attention only when orientation was the task-relevant feature and not when the contrast of the grating had to be attended. In a second experiment, observers discriminated the orientation or color of a specific lateral grating. Here, orientation-selective responses were enhanced in both tasks, but color-selective responses were enhanced only when color was task relevant. In both experiments, task-specific enhancement of feature-selective activity was not confined to the attended stimulus location but instead spread to other locations in the visual field, suggesting the concurrent involvement of a global feature-based attentional mechanism. These results suggest that attention can be remarkably selective in its ability to enhance particular task-relevant features and further reveal that increases in overall BOLD amplitude are not necessarily accompanied by improved processing of stimulus information.

Goal orientation: effects on backing up behavior, performance, efficacy, and commitment in teams.

PubMed

Porter, Christopher O L H

2005-07-01

The author examined the predictive validity of goal orientation in teams on both team process and outcome variables. Results indicate that when mean goal orientation scores were used as a way of describing team members' inputs, learning orientation was related to backing up behavior, efficacy, and commitment. The relationships between performance orientation and efficacy and commitment, however, were more complex and were clarified when task performance was also taken into account. Performance orientation had a negative effect on efficacy when task performance was low and a positive effect on commitment when task performance was high. The implications of these findings for theory and research on goal orientation in teams and team staffing are discussed. Copyright 2005 APA, all rights reserved.

Flexible Volumetric Structure

NASA Technical Reports Server (NTRS)

Cagle, Christopher M. (Inventor); Schlecht, Robin W. (Inventor)

2014-01-01

A flexible volumetric structure has a first spring that defines a three-dimensional volume and includes a serpentine structure elongatable and compressible along a length thereof. A second spring is coupled to at least one outboard edge region of the first spring. The second spring is a sheet-like structure capable of elongation along an in-plane dimension thereof. The second spring is oriented such that its in-plane dimension is aligned with the length of the first spring's serpentine structure.

Effects of high-dose ethanol intoxication and hangover on cognitive flexibility.

PubMed

Wolff, Nicole; Gussek, Philipp; Stock, Ann-Kathrin; Beste, Christian

2018-01-01

The effects of high-dose ethanol intoxication on cognitive flexibility processes are not well understood, and processes related to hangover after intoxication have remained even more elusive. Similarly, it is unknown in how far the complexity of cognitive flexibility processes is affected by intoxication and hangover effects. We performed a neurophysiological study applying high density electroencephalography (EEG) recording to analyze event-related potentials (ERPs) and perform source localization in a task switching paradigm which varied the complexity of task switching by means of memory demands. The results show that high-dose ethanol intoxication only affects task switching (i.e. cognitive flexibility processes) when memory processes are required to control task switching mechanisms, suggesting that even high doses of ethanol compromise cognitive processes when they are highly demanding. The EEG and source localization data show that these effects unfold by modulating response selection processes in the anterior cingulate cortex. Perceptual and attentional selection processes as well as working memory processes were only unspecifically modulated. In all subprocesses examined, there were no differences between the sober and hangover states, thus suggesting a fast recovery of cognitive flexibility after high-dose ethanol intoxication. We assume that the gamma-aminobutyric acid (GABAergic) system accounts for the observed effects, while they can hardly be explained by the dopaminergic system. © 2016 Society for the Study of Addiction.

Implications of flexible work systems for work studies.

PubMed

Kogi, K

1997-12-01

The relationship between changing work systems and work study methods is discussed by focusing on a recent trend toward more flexible work systems in different countries. These systems are commonly characterized by (a) uncoupling of working hours from business hours, (b) combining different atypical work forms and (c) individualized work patterns. Increased flexibility in working patterns is demanded because business hours may be covered by different workers and because special arrangements become necessary for unpopular shifts or linking separate jobs. Changes in work systems seem more successful when they are associated with (a) multiskilled work, (b) independent task implementation, (c) networked communication, (d) balanced or adjusted workload, and (e) accommodation of workers' preferences. Special attention is drawn to safety and health concerns and work-life effects. Many intervention studies done for work improvement are paying attention to multifaceted work aspects, locally available options, and participation by people. All these elements are important because prepackaged solutions do not exist. The following three views seem especially useful for action-oriented work studies: 1) Look at multiple aspects of the work, including work content and atypical work forms; 2) Know worker preferences and available options; and 3) Take into account work elements that may not be well defined, but important from local points of view. It is envisioned that these studies can provide support for a well-informed participatory process of work system changes in each local context.

Flexible goal attribution in early mindreading.

PubMed

Michael, John; Christensen, Wayne

2016-03-01

The 2-systems theory developed by Apperly and Butterfill (2009; Butterfill & Apperly, 2013) is an influential approach to explaining the success of infants and young children on implicit false-belief tasks. There is extensive empirical and theoretical work examining many aspects of this theory, but little attention has been paid to the way in which it characterizes goal attribution. We argue here that this aspect of the theory is inadequate. Butterfill and Apperly's characterization of goal attribution is designed to show how goals could be ascribed by infants without representing them as related to other psychological states, and the minimal mindreading system is supposed to operate without employing flexible semantic-executive cognitive processes. But research on infant goal attribution reveals that infants exhibit a high degree of situational awareness that is strongly suggestive of flexible semantic-executive cognitive processing, and infants appear moreover to be sensitive to interrelations between goals, preferences, and beliefs. Further, close attention to the structure of implicit mindreading tasks--for which the theory was specifically designed--indicates that flexible goal attribution is required to succeed. We conclude by suggesting 2 approaches to resolving these problems. (c) 2016 APA, all rights reserved).

Caudate Nucleus Volume Mediates the Link between Cardiorespiratory Fitness and Cognitive Flexibility in Older Adults

PubMed Central

Verstynen, Timothy D.; Lynch, Brighid; Miller, Destiny L.; Voss, Michelle W.; Prakash, Ruchika Shaurya; Chaddock, Laura; Basak, Chandramallika; Szabo, Amanda; Olson, Erin A.; Wojcicki, Thomas R.; Fanning, Jason; Gothe, Neha P.; McAuley, Edward; Kramer, Arthur F.; Erickson, Kirk I.

2012-01-01

The basal ganglia play a central role in regulating the response selection abilities that are critical for mental flexibility. In neocortical areas, higher cardiorespiratory fitness levels are associated with increased gray matter volume, and these volumetric differences mediate enhanced cognitive performance in a variety of tasks. Here we examine whether cardiorespiratory fitness correlates with the volume of the subcortical nuclei that make up the basal ganglia and whether this relationship predicts cognitive flexibility in older adults. Structural MRI was used to determine the volume of the basal ganglia nuclei in a group of older, neurologically healthy individuals (mean age 66 years, N = 179). Measures of cardiorespiratory fitness (VO2max), cognitive flexibility (task switching), and attentional control (flanker task) were also collected. Higher fitness levels were correlated with higher accuracy rates in the Task Switching paradigm. In addition, the volume of the caudate nucleus, putamen, and globus pallidus positively correlated with Task Switching accuracy. Nested regression modeling revealed that caudate nucleus volume was a significant mediator of the relationship between cardiorespiratory fitness, and task switching performance. These findings indicate that higher cardiorespiratory fitness predicts better cognitive flexibility in older adults through greater grey matter volume in the dorsal striatum. PMID:22900181

Six principles to enhance health workforce flexibility.

PubMed

Nancarrow, Susan A

2015-04-07

This paper proposes approaches to break down the boundaries that reduce the ability of the health workforce to respond to population needs, or workforce flexibility. Accessible health services require sufficient numbers and types of skilled workers to meet population needs. However, there are several reasons that the health workforce cannot or does not meet population needs. These primarily stem from workforce shortages. However, the health workforce can also be prevented from responding appropriately and efficiently because of restrictions imposed by professional boundaries, funding models or therapeutic partitions. These boundaries limit the ability of practitioners to effectively diagnose and treat patients by restricting access to specific skills, technologies and services. In some cases, these boundaries not only reduce workforce flexibility, but they introduce inefficiencies in the form of additional clinical transactions and costs, further detracting from workforce responsiveness. Several new models of care are being developed to enhance workforce flexibility by enabling existing staff to work to their full scope of practice, extend their roles or by introducing new workers. Expanding on these concepts, this theoretical paper proposes six principles that have the potential to enhance health workforce flexibility, specifically: 1. Measure health system performance from the perspective of the patient. 2. Minimise training times. 3. Regulate tasks (competencies), not professions. 4. Match rewards and indemnity to the levels of skill and risk required to perform a particular task, not professional title. 5. Ensure that practitioners have all the skills they need to perform the tasks required to work in the environment in which they work 6. Enable practitioners to work to their full scope of practice delegate tasks where required These proposed principles will challenge some of the existing social norms around health-care delivery; however, many of these

Learning outdoors: male lizards show flexible spatial learning under semi-natural conditions

PubMed Central

Noble, Daniel W. A.; Carazo, Pau; Whiting, Martin J.

2012-01-01

Spatial cognition is predicted to be a fundamental component of fitness in many lizard species, and yet some studies suggest that it is relatively slow and inflexible. However, such claims are based on work conducted using experimental designs or in artificial contexts that may underestimate their cognitive abilities. We used a biologically realistic experimental procedure (using simulated predatory attacks) to study spatial learning and its flexibility in the lizard Eulamprus quoyii in semi-natural outdoor enclosures under similar conditions to those experienced by lizards in the wild. To evaluate the flexibility of spatial learning, we conducted a reversal spatial-learning task in which positive and negative reinforcements of learnt spatial stimuli were switched. Nineteen (32%) male lizards learnt both tasks within 10 days (spatial task mean: 8.16 ± 0.69 (s.e.) and reversal spatial task mean: 10.74 ± 0.98 (s.e.) trials). We demonstrate that E. quoyii are capable of flexible spatial learning and suggest that future studies focus on a range of lizard species which differ in phylogeny and/or ecology, using biologically relevant cognitive tasks, in an effort to bridge the cognitive divide between ecto- and endotherms. PMID:23075525

Relationships between cooperation and goal orientation among male professional and semi-professional team athletes.

PubMed

Lameiras, João; Almeida, Pedro L; Garcia-Mas, Alexandre

2014-12-01

In team sports, athletes' goals may focus on the task (enhancing performance, developing better skills, etc.) or on ego (being better than the others, achieving superiority, etc.). This study investigated the relationships between athletes' goal orientation and their tendency to cooperate with teammates and coaches. 158 professional men (M age = 24.1 yr., SD = 4.6) who played on various sport teams participated in this study. Goal orientation was measured with the Portuguese version of the Task and Ego Orientation in Sport Questionnaire, and cooperation was measured with the Questionário de Cooperação Desportiva. Cooperation was positively correlated with task orientation, and negatively correlated with ego orientation. Overall, the findings support that in sports, directing the players' focus on task may promote prosocial behavior.

Process Versus Task in Social Planning

ERIC Educational Resources Information Center

Gilbert, Neil; Specht, Harry

1977-01-01

For several decades, the relative importance of process as opposed to task has been an issue in the literature. This study of the Model Cities program examines the relationship between program outcomes and the process and task orientations of program planners. (Author)

A task-irrelevant stimulus attribute affects perception and short-term memory

PubMed Central

Huang, Jie; Kahana, Michael J.; Sekuler, Robert

2010-01-01

Selective attention protects cognition against intrusions of task-irrelevant stimulus attributes. This protective function was tested in coordinated psychophysical and memory experiments. Stimuli were superimposed, horizontally and vertically oriented gratings of varying spatial frequency; only one orientation was task relevant. Experiment 1 demonstrated that a task-irrelevant spatial frequency interfered with visual discrimination of the task-relevant spatial frequency. Experiment 2 adopted a two-item Sternberg task, using stimuli that had been scaled to neutralize interference at the level of vision. Despite being visually neutralized, the task-irrelevant attribute strongly influenced recognition accuracy and associated reaction times (RTs). This effect was sharply tuned, with the task-irrelevant spatial frequency having an impact only when the task-relevant spatial frequencies of the probe and study items were highly similar to one another. Model-based analyses of judgment accuracy and RT distributional properties converged on the point that the irrelevant orientation operates at an early stage in memory processing, not at a later one that supports decision making. PMID:19933454

Cueing cognitive flexibility: Item-specific learning of switch readiness.

PubMed

Chiu, Yu-Chin; Egner, Tobias

2017-12-01

The rich behavioral repertoire of the human species derives from our ability to flexibly reconfigure processing strategies (task sets) in response to changing requirements. This updating of task sets is effortful, as reflected by longer response times when switching a task than repeating it (switch costs). However, some recent data suggest that switch costs can be reduced by cueing switch readiness bottom-up, by associating particular stimuli with frequent switch requirements. This type of "stimulus-control (S-C) learning" would be highly adaptive, as it combines the speed of automatic (bottom-up) processing with the flexibility and generalizability of controlled (top-down) processing. However, it is unclear whether S-C learning of switch readiness is truly possible, and what the underlying mechanisms are. Here we address these questions by pairing specific stimuli with a need to update task-sets either frequently or rarely. In all 3 experiments, we observe robust item-specific switch probability (ISSP) effects as revealed by smaller switch costs for frequent switch items than for rare switch items. By including a neutral condition, we also show that the ISSP effect is primarily driven by S-C learning reducing switch costs in frequent switch items. Furthermore, by employing 3 tasks in Experiment 3, we establish that the ISSP effect reflects an enhancement of general switch readiness, rather than of the readiness to switch to a specific alternate task. These results firmly establish that switch readiness is malleable by item-specific S-C learning processes, documenting that a generalizable state of cognitive flexibility can be primed by a bottom-up stimulus. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Precision pointing and control of flexible spacecraft

NASA Technical Reports Server (NTRS)

Bantell, M. H., Jr.

1987-01-01

The problem and long term objectives for the precision pointing and control of flexible spacecraft are given. The four basic objectives are stated in terms of two principle tasks. Under Task 1, robust low order controllers, improved structural modeling methods for control applications and identification methods for structural dynamics are being developed. Under Task 2, a lab test experiment for verification of control laws and system identification algorithms is being developed. For Task 1, work has focused on robust low order controller design and some initial considerations for structural modeling in control applications. For Task 2, work has focused on experiment design and fabrication, along with sensor selection and initial digital controller implementation. Conclusions are given.

Progress on control experiments of flexible structures

NASA Technical Reports Server (NTRS)

Juang, Jer-Nan

1990-01-01

Progress at the NASA Langley Research Center in the area of control experiments for flexible structures is described. First the author presents the experimental results for a linear model which represents slewing maneuvers of a generic space station solar panel carried out to evaluate experimentally some control technologies. Then the status of the rotational/translational maneuvering experiment of a flexible steel panel carried by a translation cart is presented. Finally, experimental results of the NASA minimast testbed using velocity command stepper motors as reaction mass reactors are shown. All the test configurations are briefly described, including actuator and sensor, test setup, and test software. The status of some research activities oriented primarily to the experimental methods for control of flexible structures is presented.

A variational approach to dynamics of flexible multibody systems

NASA Technical Reports Server (NTRS)

Wu, Shih-Chin; Haug, Edward J.; Kim, Sung-Soo

1989-01-01

This paper presents a variational formulation of constrained dynamics of flexible multibody systems, using a vector-variational calculus approach. Body reference frames are used to define global position and orientation of individual bodies in the system, located and oriented by position of its origin and Euler parameters, respectively. Small strain linear elastic deformation of individual components, relative to their body references frames, is defined by linear combinations of deformation modes that are induced by constraint reaction forces and normal modes of vibration. A library of kinematic couplings between flexible and/or rigid bodies is defined and analyzed. Variational equations of motion for multibody systems are obtained and reduced to mixed differential-algebraic equations of motion. A space structure that must deform during deployment is analyzed, to illustrate use of the methods developed.

Manipulating flexible parts using a teleoperated system with time delay: An experiment

NASA Technical Reports Server (NTRS)

Kotoku, T.; Takamune, K.; Tanie, K.; Komoriya, K.; Matsuhira, N.; Asakura, M.; Bamba, H.

1994-01-01

This paper reports experiments involving the handling of flexible parts (e.g. wires) when using a teleoperated system with time delay. The task is principally a peg-in-hole task involving the wrapping of a wire around two posts on the task-board. It is difficult to estimate the effects of the flexible parts; therefore, on-line teleoperation is indispensable for this class of unpredictable task. We first propose a teleoperation system based on the predictive image display, then describe an experimental teleoperation testbed with a four second transmission time delay. Finally, we report on wire handling operations that were performed to evaluate the performance of this system. Those experiments will contribute to future advanced experiments for the MITI ETS-7 mission.

The effects of lesions of the superior colliculus on locomotor orientation and the orienting reflex in the rat.

PubMed

Goodale, M A; Murison, R C

1975-05-02

The effects of bilateral removal of the superior colliculus or visual cortex on visually guided locomotor movements in rats performing a brightness discrimination task were investigated directly with the use of cine film. Rats with collicular lesions showed patterns of locomotion comparable to or more efficient than those of normal animals when approaching one of 5 small doors located at one end of a large open area. In contrast, animals with large but incomplete lesions of visual cortex were distinctly impaired in their visual control of approach responses to the same stimuli. On the other hand, rats with collicular damage showed no orienting reflex or evidence of distraction in the same task when novel visual or auditory stimuli were presented. However, both normal and visual-decorticate rats showed various components of the orienting reflex and disturbance in task performance when the same novel stimuli were presented. These results suggest that although the superior colliculus does not appear to be essential to the visual control of locomotor orientation, this midbrain structure might participate in the mediation of shifts in visual fixation and attention. Visual cortex, while contributing to visuospatial guidance of locomotor movements, might not play a significant role in the control and integration of the orienting reflex.

Is Adaptation to Task Complexity Really Beneficial for Performance?

ERIC Educational Resources Information Center

Pieschl, Stephanie; Stahl, Elmar; Murray, Tom; Bromme, Rainer

2012-01-01

Theories of self-regulated learning assume that learners flexibly adapt their learning process to external task demands and that this is positively related to performance. In this study, university students (n = 119) solved three tasks that greatly differed in complexity. Their learning processes were captured in detail by task-specific…

Flexible ultrasonic pipe inspection apparatus

DOEpatents

Jenkins, C.F.; Howard, B.D.

1998-06-23

A flexible, modular ultrasonic pipe inspection apparatus, comprises a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present. 7 figs.

Flexible ultrasonic pipe inspection apparatus

DOEpatents

Jenkins, Charles F.; Howard, Boyd D.

1998-01-01

A flexible, modular ultrasonic pipe inspection apparatus, comprising a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present.

Goal Orientations of General Chemistry Students via the Achievement Goal Framework

ERIC Educational Resources Information Center

Lewis, Scott E.

2018-01-01

The Achievement Goal Framework describes students' goal orientations as: task-based, focusing on the successful completion of the task; self-based, evaluating performance relative to one's own past performance; or other-based, evaluating performance relative to the performance of others. Goal orientations have been used to explain student success…

Sexual orientation and spatial memory.

PubMed

Cánovas, Ma Rosa; Cimadevilla, José Manuel

2011-11-01

The present study aimed at determining the influence of sexual orientation in human spatial learning and memory. Participants performed the Boxes Room, a virtual reality version of the Holeboard. In Experiment I, a reference memory task, the position of the hidden rewards remained constant during the whole experiment. In Experiment II, a working memory task, the position of rewards changed between blocks. Each block consisted of two trials: One trial for acquisition and another for retrieval. The results of Experiment I showed that heterosexual men performed better than homosexual men and heterosexual women. They found the rewarded boxes faster. Moreover, homosexual participants committed more errors than heterosexuals. Experiment II showed that working memory abilities are the same in groups of different sexual orientation. These results suggest that sexual orientation is related to spatial navigation abilities, but mostly in men, and limited to reference memory, which depends more on the function of the hippocampal system.

Apparatus And Method Of Using Flexible Printed Circuit Board In Optical Transceiver Device

DOEpatents

Anderson, Gene R.; Armendariz, Marcelino G.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reysen, Bill H.

2005-03-15

This invention relates to a flexible printed circuit board that is used in connection with an optical transmitter, receiver or transceiver module. In one embodiment, the flexible printed circuit board has flexible metal layers in between flexible insulating layers, and the circuit board comprises: (1) a main body region orientated in a first direction having at least one electrical or optoelectronic device; (2) a plurality of electrical contact pads integrated into the main body region, where the electrical contact pads function to connect the flexible printed circuit board to an external environment; (3) a buckle region extending from one end of the main body region; and (4) a head region extending from one end of the buckle region, and where the head region is orientated so that it is at an angle relative to the direction of the main body region. The electrical contact pads may be ball grid arrays, solder balls or land-grid arrays, and they function to connect the circuit board to an external environment. A driver or amplifier chip may be adapted to the head region of the flexible printed circuit board. In another embodiment, a heat spreader passes along a surface of the head region of the flexible printed circuit board, and a window is formed in the head region of the flexible printed circuit board. Optoelectronic devices are adapted to the head spreader in such a manner that they are accessible through the window in the flexible printed circuit board.

Socio-Emotional Orientations and Teacher Change

ERIC Educational Resources Information Center

Kaasila, Raimo; Hannula, Markku S.; Laine, Anu; Pehkonen, Erkki

2008-01-01

In this article we consider how elementary education students' views of mathematics changed during their mathematics methods course. We focus on four female students: two started the course with mainly positive views of mathematics and a task orientation, two with negative views of the subject and an ego-defensive orientation. The biggest change…

Large planar maneuvers for articulated flexible manipulators

NASA Technical Reports Server (NTRS)

Huang, Jen-Kuang; Yang, Li-Farn

1988-01-01

An articulated flexible manipulator carried on a translational cart is maneuvered by an active controller to perform certain position control tasks. The nonlinear dynamics of the articulated flexible manipulator are derived and a transformation matrix is formulated to localize the nonlinearities within the inertia matrix. Then a feedback linearization scheme is introduced to linearize the dynamic equations for controller design. Through a pole placement technique, a robust controller design is obtained by properly assigning a set of closed-loop desired eigenvalues to meet performance requirements. Numerical simulations for the articulated flexible manipulators are given to demonstrate the feasibility and effectiveness of the proposed position control algorithms.

A Chaotic Particle Swarm Optimization-Based Heuristic for Market-Oriented Task-Level Scheduling in Cloud Workflow Systems

PubMed Central

Li, Xuejun; Xu, Jia; Yang, Yun

2015-01-01

Cloud workflow system is a kind of platform service based on cloud computing. It facilitates the automation of workflow applications. Between cloud workflow system and its counterparts, market-oriented business model is one of the most prominent factors. The optimization of task-level scheduling in cloud workflow system is a hot topic. As the scheduling is a NP problem, Ant Colony Optimization (ACO) and Particle Swarm Optimization (PSO) have been proposed to optimize the cost. However, they have the characteristic of premature convergence in optimization process and therefore cannot effectively reduce the cost. To solve these problems, Chaotic Particle Swarm Optimization (CPSO) algorithm with chaotic sequence and adaptive inertia weight factor is applied to present the task-level scheduling. Chaotic sequence with high randomness improves the diversity of solutions, and its regularity assures a good global convergence. Adaptive inertia weight factor depends on the estimate value of cost. It makes the scheduling avoid premature convergence by properly balancing between global and local exploration. The experimental simulation shows that the cost obtained by our scheduling is always lower than the other two representative counterparts. PMID:26357510

Behavioral and Neural Markers of Flexible Attention over Working Memory in Aging

PubMed Central

Mok, Robert M.; Myers, Nicholas E.; Wallis, George; Nobre, Anna Christina

2016-01-01

Working memory (WM) declines as we age and, because of its fundamental role in higher order cognition, this can have highly deleterious effects in daily life. We investigated whether older individuals benefit from flexible orienting of attention within WM to mitigate cognitive decline. We measured magnetoencephalography (MEG) in older adults performing a WM precision task with cues during the maintenance period that retroactively predicted the location of the relevant items for performance (retro-cues). WM performance of older adults significantly benefitted from retro-cues. Whereas WM maintenance declined with age, retro-cues conferred strong attentional benefits. A model-based analysis revealed an increase in the probability of recalling the target, a lowered probability of retrieving incorrect items or guessing, and an improvement in memory precision. MEG recordings showed that retro-cues induced a transient lateralization of alpha (8–14 Hz) and beta (15–30 Hz) oscillatory power. Interestingly, shorter durations of alpha/beta lateralization following retro-cues predicted larger cueing benefits, reinforcing recent ideas about the dynamic nature of access to WM representations. Our results suggest that older adults retain flexible control over WM, but individual differences in control correspond to differences in neural dynamics, possibly reflecting the degree of preservation of control in healthy aging. PMID:26865653

Behavioral and Neural Markers of Flexible Attention over Working Memory in Aging.

PubMed

Mok, Robert M; Myers, Nicholas E; Wallis, George; Nobre, Anna Christina

2016-04-01

Working memory (WM) declines as we age and, because of its fundamental role in higher order cognition, this can have highly deleterious effects in daily life. We investigated whether older individuals benefit from flexible orienting of attention within WM to mitigate cognitive decline. We measured magnetoencephalography (MEG) in older adults performing a WM precision task with cues during the maintenance period that retroactively predicted the location of the relevant items for performance (retro-cues). WM performance of older adults significantly benefitted from retro-cues. Whereas WM maintenance declined with age, retro-cues conferred strong attentional benefits. A model-based analysis revealed an increase in the probability of recalling the target, a lowered probability of retrieving incorrect items or guessing, and an improvement in memory precision. MEG recordings showed that retro-cues induced a transient lateralization of alpha (8-14 Hz) and beta (15-30 Hz) oscillatory power. Interestingly, shorter durations of alpha/beta lateralization following retro-cues predicted larger cueing benefits, reinforcing recent ideas about the dynamic nature of access to WM representations. Our results suggest that older adults retain flexible control over WM, but individual differences in control correspond to differences in neural dynamics, possibly reflecting the degree of preservation of control in healthy aging. © The Author 2016. Published by Oxford University Press.

Task-dependent color discrimination

NASA Technical Reports Server (NTRS)

Poirson, Allen B.; Wandell, Brian A.

1990-01-01

When color video displays are used in time-critical applications (e.g., head-up displays, video control panels), the observer must discriminate among briefly presented targets seen within a complex spatial scene. Color-discrimination threshold are compared by using two tasks. In one task the observer makes color matches between two halves of a continuously displayed bipartite field. In a second task the observer detects a color target in a set of briefly presented objects. The data from both tasks are well summarized by ellipsoidal isosensitivity contours. The fitted ellipsoids differ both in their size, which indicates an absolute sensitivity difference, and orientation, which indicates a relative sensitivity difference.

Working Memory and Cognitive Flexibility Mediates Visuoconstructional Abilities in Older Adults with Heterogeneous Cognitive Ability.

PubMed

Ávila, Rafaela T; de Paula, Jonas J; Bicalho, Maria A; Moraes, Edgar N; Nicolato, Rodrigo; Malloy-Diniz, Leandro F; Diniz, Breno S

2015-05-01

Previous studies suggest that executive functions influence the performance on visuoconstructional tasks. This study aims to investigate whether the relationship between planning ability and the copy of complex figures is mediated by distinct components of executive functions (i.e., working memory, inhibitory control and cognitive flexibility). We included a 129 older adults with Alzheimer's disease (n=36, AD), mild cognitive impairment (MCI, n=67), and with no evidence of cognitive impairment (controls, n=26). We evaluated the mediation effect of planning abilities, working memory, cognitive flexibility and inhibitory control on visuoconstructional tasks using a multiple mediation models. We found a significant direct effect of planning on visuoconstructional abilities and a partial mediation effect of working memory and cognitive flexibility on visuoconstructional abilities. The present results indicate that the performance on visuoconstructional task is mediated by multiple interrelated executive functions components, in particular working memory and cognitive flexibility.

Cost analysis of concepts for a demand oriented biogas supply for flexible power generation.

PubMed

Hahn, Henning; Ganagin, Waldemar; Hartmann, Kilian; Wachendorf, Michael

2014-10-01

With the share of intermittent renewable energies within the electricity system rising, balancing services from dispatchable power plants are of increasing importance. Highlighting the importance of the need to keeping fuel costs for flexible power generation to a minimum, the study aims to identify favourable biogas plant configurations, supplying biogas on demand. A cost analysis of five configurations based on biogas storing and flexible biogas production concepts has been carried out. Results show that additional flexibility costs for a biogas supply of 8h per day range between 2€ and 11€MWh(-1) and for a 72h period without biogas demand from 9€ to 19€MWh(-1). While biogas storage concepts were identified as favourable short term supply configurations, flexible biogas production concepts profit from reduced storage requirements at plants with large biogas production capacities or for periods of several hours without biogas demand. Copyright © 2014 Elsevier Ltd. All rights reserved.

Architecting Service-Oriented Systems

DTIC Science & Technology

2011-08-01

Abstract Service orientation is an approach to software systems development that has become a popular way to implement distributed, loosely coupled...runtime. The later you defer binding the more flexibility service providers and service consumers have to develop their software systems independently...Enterprise Service Bus An Enterprise Service Bus (ESB) is a software pattern that can be part of a SOA infrastructure and acts as an intermediary

Orientation Transfer in Vernier and Stereoacuity Training.

PubMed

Snell, Nathaniel; Kattner, Florian; Rokers, Bas; Green, C Shawn

2015-01-01

Human performance on various visual tasks can be improved substantially via training. However, the enhancements are frequently specific to relatively low-level stimulus dimensions. While such specificity has often been thought to be indicative of a low-level neural locus of learning, recent research suggests that these same effects can be accounted for by changes in higher-level areas--in particular in the way higher-level areas read out information from lower-level areas in the service of highly practiced decisions. Here we contrast the degree of orientation transfer seen after training on two different tasks--vernier acuity and stereoacuity. Importantly, while the decision rule that could improve vernier acuity (i.e. a discriminant in the image plane) would not be transferable across orientations, the simplest rule that could be learned to solve the stereoacuity task (i.e. a discriminant in the depth plane) would be insensitive to changes in orientation. Thus, given a read-out hypothesis, more substantial transfer would be expected as a result of stereoacuity than vernier acuity training. To test this prediction, participants were trained (7500 total trials) on either a stereoacuity (N = 9) or vernier acuity (N = 7) task with the stimuli in either a vertical or horizontal configuration (balanced across participants). Following training, transfer to the untrained orientation was assessed. As predicted, evidence for relatively orientation specific learning was observed in vernier trained participants, while no evidence of specificity was observed in stereo trained participants. These results build upon the emerging view that perceptual learning (even very specific learning effects) may reflect changes in inferences made by high-level areas, rather than necessarily fully reflecting changes in the receptive field properties of low-level areas.

Physically coupling two objects in a bimanual task alters kinematics but not end-state comfort.

PubMed

Hughes, Charmayne M L; Haddad, Jeffrey M; Franz, Elizabeth A; Zelaznik, Howard N; Ryu, Joong Hyun

2011-06-01

People often grasp objects with an awkward grip to ensure a comfortable hand posture at the end of the movement. This end-state comfort effect is a predominant constraint during unimanual movements. However, during bimanual movements the tendency for both hands to satisfy end-state comfort is affected by factors such as end-orientation congruency and task context. Although bimanual end-state comfort has been examined when the hands manipulate two independent objects, no research has examined end-state comfort when the hands are required to manipulate two physically-coupled objects. In the present experiment, kinematics and grasp behavior during a unimanual and bimanual reaching and placing tasks were examined, when the hands manipulate two physically-connected objects. Forty-five participants were assigned to one of three groups; unimanual, bimanual no-spring (the objects were not physically connected), and bimanual spring (the objects were connected by a spring), and instructed to grasp and place objects in various end-orientations, depending on condition. Physically connecting the objects did not affect end-state comfort prevalence. However, it resulted in decreased interlimb coupling. This finding supports the notion of a flexible constraint hierarchy, in which action goals guide the selection of lower level action features (i.e., hand grip used for grasping), and the particular movements used to accomplish that goal (i.e., interlimb coupling) are controlled throughout the movement.

Flexible missile autopilot design studies with PC-MATLAB/386

NASA Technical Reports Server (NTRS)

Ruth, Michael J.

1989-01-01

Development of a responsive, high-bandwidth missile autopilot for airframes which have structural modes of unusually low frequency presents a challenging design task. Such systems are viable candidates for modern, state-space control design methods. The PC-MATLAB interactive software package provides an environment well-suited to the development of candidate linear control laws for flexible missile autopilots. The strengths of MATLAB include: (1) exceptionally high speed (MATLAB's version for 80386-based PC's offers benchmarks approaching minicomputer and mainframe performance); (2) ability to handle large design models of several hundred degrees of freedom, if necessary; and (3) broad extensibility through user-defined functions. To characterize MATLAB capabilities, a simplified design example is presented. This involves interactive definition of an observer-based state-space compensator for a flexible missile autopilot design task. MATLAB capabilities and limitations, in the context of this design task, are then summarized.

Perceptual learning of basic visual features remains task specific with Training-Plus-Exposure (TPE) training.

PubMed

Cong, Lin-Juan; Wang, Ru-Jie; Yu, Cong; Zhang, Jun-Yun

2016-01-01

Visual perceptual learning is known to be specific to the trained retinal location, feature, and task. However, location and feature specificity can be eliminated by double-training or TPE training protocols, in which observers receive additional exposure to the transfer location or feature dimension via an irrelevant task besides the primary learning task Here we tested whether these new training protocols could even make learning transfer across different tasks involving discrimination of basic visual features (e.g., orientation and contrast). Observers practiced a near-threshold orientation (or contrast) discrimination task. Following a TPE training protocol, they also received exposure to the transfer task via performing suprathreshold contrast (or orientation) discrimination in alternating blocks of trials in the same sessions. The results showed no evidence for significant learning transfer to the untrained near-threshold contrast (or orientation) discrimination task after discounting the pretest effects and the suprathreshold practice effects. These results thus do not support a hypothetical task-independent component in perceptual learning of basic visual features. They also set the boundary of the new training protocols in their capability to enable learning transfer.

Mental traveling along psychological distances: The effects of cultural syndromes, perspective flexibility, and construal level.

PubMed

Wong, Vincent Chi; Wyer, Robert S

2016-07-01

Individuals' psychological distance from the stimuli they encounter in daily life can influence the abstractness or generality of the mental representations they form of these stimuli. However, these representations can also depend on the perspective from which the stimuli are construed. When individuals have either an individualistic social orientation or a short-term temporal orientation, they construe psychologically distal events more globally than they construe proximal ones, as implied by construal level theory (Trope & Liberman, 2010). When they have either a collectivistic social orientation or a long-term temporal orientation, however, they not only construe the implications of distal events more concretely than individuals with an egocentric perspective but also construe the implications of proximal events in more abstract terms. These effects are mediated by the flexibility of the perspectives that people take when they make judgments. Differences in perspective flexibility account for the impact of both situationally induced differences in social and temporal orientation and more chronic cultural differences in these orientations. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Childrearing Antecedents of Flexible Thinking.

ERIC Educational Resources Information Center

Busse, Thomas V.

The behavior, attitudes, and social class of 48 Negro mothers and 48 Negro fathers were related to the development of their fifth grade boys' flexible thinking, defined as the ability to consider alternative means to a given end. The parents were interviewed at home and asked to teach their sons four tasks. Linear relationships were found linking…

a Task-Driven Disaster Data Link Approach

NASA Astrophysics Data System (ADS)

Qiu, L. Y.; Zhu, Q.; Gu, J. Y.; Du, Z. Q.

2015-08-01

With the rapid development of sensor networks and Earth observation technology, a large quantity of disaster-related data is available, such as remotely sensed data, historic data, cases data, simulation data, disaster products and so on. However, the efficiency of current data management and service systems has become increasingly serious due to the task variety and heterogeneous data. For emergency task-oriented applications, data searching mainly relies on artificial experience based on simple metadata index, whose high time-consuming and low accuracy cannot satisfy the requirements of disaster products on velocity and veracity. In this paper, a task-oriented linking method is proposed for efficient disaster data management and intelligent service, with the objectives of 1) putting forward ontologies of disaster task and data to unify the different semantics of multi-source information, 2) identifying the semantic mapping from emergency tasks to multiple sources on the basis of uniform description in 1), 3) linking task-related data automatically and calculating the degree of correlation between each data and a target task. The method breaks through traditional static management of disaster data and establishes a base for intelligent retrieval and active push of disaster information. The case study presented in this paper illustrates the use of the method with a flood emergency relief task.

Nucleus accumbens dopamine D2-receptor expressing neurons control behavioral flexibility in a place discrimination task in the IntelliCage.

PubMed

Macpherson, Tom; Morita, Makiko; Wang, Yanyan; Sasaoka, Toshikuni; Sawa, Akira; Hikida, Takatoshi

2016-07-01

Considerable evidence has demonstrated a critical role for the nucleus accumbens (NAc) in the acquisition and flexibility of behavioral strategies. These processes are guided by the activity of two discrete neuron types, dopamine D1- or D2-receptor expressing medium spiny neurons (D1-/D2-MSNs). Here we used the IntelliCage, an automated group-housing experimental cage apparatus, in combination with a reversible neurotransmission blocking technique to examine the role of NAc D1- and D2-MSNs in the acquisition and reversal learning of a place discrimination task. We demonstrated that NAc D1- and D2-MSNs do not mediate the acquisition of the task, but that suppression of activity in D2-MSNs impairs reversal learning and increased perseverative errors. Additionally, global knockout of the dopamine D2L receptor isoform produced a similar behavioral phenotype to D2-MSN-blocked mice. These results suggest that D2L receptors and NAc D2-MSNs act to suppress the influence of previously correct behavioral strategies allowing transfer of behavioral control to new strategies. © 2016 Macpherson et al.; Published by Cold Spring Harbor Laboratory Press.

Robotic virtual reality simulation plus standard robotic orientation versus standard robotic orientation alone: a randomized controlled trial.

PubMed

Vaccaro, Christine M; Crisp, Catrina C; Fellner, Angela N; Jackson, Christopher; Kleeman, Steven D; Pavelka, James

2013-01-01

The objective of this study was to compare the effect of virtual reality simulation training plus robotic orientation versus robotic orientation alone on performance of surgical tasks using an inanimate model. Surgical resident physicians were enrolled in this assessor-blinded randomized controlled trial. Residents were randomized to receive either (1) robotic virtual reality simulation training plus standard robotic orientation or (2) standard robotic orientation alone. Performance of surgical tasks was assessed at baseline and after the intervention. Nine of 33 modules from the da Vinci Skills Simulator were chosen. Experts in robotic surgery evaluated each resident's videotaped performance of the inanimate model using the Global Rating Scale (GRS) and Objective Structured Assessment of Technical Skills-modified for robotic-assisted surgery (rOSATS). Nine resident physicians were enrolled in the simulation group and 9 in the control group. As a whole, participants improved their total time, time to incision, and suture time from baseline to repeat testing on the inanimate model (P = 0.001, 0.003, <0.001, respectively). Both groups improved their GRS and rOSATS scores significantly (both P < 0.001); however, the GRS overall pass rate was higher in the simulation group compared with the control group (89% vs 44%, P = 0.066). Standard robotic orientation and/or robotic virtual reality simulation improve surgical skills on an inanimate model, although this may be a function of the initial "practice" on the inanimate model and repeat testing of a known task. However, robotic virtual reality simulation training increases GRS pass rates consistent with improved robotic technical skills learned in a virtual reality environment.

Spatial Orienting of Attention in Dyslexic Adults Using Directional and Alphabetic Cues

ERIC Educational Resources Information Center

Judge, Jeannie; Knox, Paul C.; Caravolas, Marketa

2013-01-01

Spatial attention performance was investigated in adults with dyslexia. Groups with and without dyslexia completed literacy/phonological tasks as well as two spatial cueing tasks, in which attention was oriented in response to a centrally presented pictorial (arrow) or alphabetic (letter) cue. Cued response times and orienting effects were largely…

Biologically plausible learning in recurrent neural networks reproduces neural dynamics observed during cognitive tasks

PubMed Central

Miconi, Thomas

2017-01-01

Neural activity during cognitive tasks exhibits complex dynamics that flexibly encode task-relevant variables. Chaotic recurrent networks, which spontaneously generate rich dynamics, have been proposed as a model of cortical computation during cognitive tasks. However, existing methods for training these networks are either biologically implausible, and/or require a continuous, real-time error signal to guide learning. Here we show that a biologically plausible learning rule can train such recurrent networks, guided solely by delayed, phasic rewards at the end of each trial. Networks endowed with this learning rule can successfully learn nontrivial tasks requiring flexible (context-dependent) associations, memory maintenance, nonlinear mixed selectivities, and coordination among multiple outputs. The resulting networks replicate complex dynamics previously observed in animal cortex, such as dynamic encoding of task features and selective integration of sensory inputs. We conclude that recurrent neural networks offer a plausible model of cortical dynamics during both learning and performance of flexible behavior. DOI: http://dx.doi.org/10.7554/eLife.20899.001 PMID:28230528

Biologically plausible learning in recurrent neural networks reproduces neural dynamics observed during cognitive tasks.

PubMed

Miconi, Thomas

2017-02-23

Neural activity during cognitive tasks exhibits complex dynamics that flexibly encode task-relevant variables. Chaotic recurrent networks, which spontaneously generate rich dynamics, have been proposed as a model of cortical computation during cognitive tasks. However, existing methods for training these networks are either biologically implausible, and/or require a continuous, real-time error signal to guide learning. Here we show that a biologically plausible learning rule can train such recurrent networks, guided solely by delayed, phasic rewards at the end of each trial. Networks endowed with this learning rule can successfully learn nontrivial tasks requiring flexible (context-dependent) associations, memory maintenance, nonlinear mixed selectivities, and coordination among multiple outputs. The resulting networks replicate complex dynamics previously observed in animal cortex, such as dynamic encoding of task features and selective integration of sensory inputs. We conclude that recurrent neural networks offer a plausible model of cortical dynamics during both learning and performance of flexible behavior.

Neurons in Primary Motor Cortex Encode Hand Orientation in a Reach-to-Grasp Task.

PubMed

Ma, Chaolin; Ma, Xuan; Fan, Jing; He, Jiping

2017-08-01

It is disputed whether those neurons in the primary motor cortex (M1) that encode hand orientation constitute an independent channel for orientation control in reach-to-grasp behaviors. Here, we trained two monkeys to reach forward and grasp objects positioned in the frontal plane at different orientation angles, and simultaneously recorded the activity of M1 neurons. Among the 2235 neurons recorded in M1, we found that 18.7% had a high correlation exclusively with hand orientation, 15.9% with movement direction, and 29.5% with both movement direction and hand orientation. The distributions of neurons encoding hand orientation and those encoding movement direction were not uniform but coexisted in the same region. The trajectory of hand rotation was reproduced by the firing patterns of the orientation-related neurons independent of the hand reaching direction. These results suggest that hand orientation is an independent component for the control of reaching and grasping activity.

Practical experience with graphical user interfaces and object-oriented design in the clinical laboratory.

PubMed

Wells, I G; Cartwright, R Y; Farnan, L P

1993-12-15

The computing strategy in our laboratories evolved from research in Artificial Intelligence, and is based on powerful software tools running on high performance desktop computers with a graphical user interface. This allows most tasks to be regarded as design problems rather than implementation projects, and both rapid prototyping and an object-oriented approach to be employed during the in-house development and enhancement of the laboratory information systems. The practical application of this strategy is discussed, with particular reference to the system designer, the laboratory user and the laboratory customer. Routine operation covers five departments, and the systems are stable, flexible and well accepted by the users. Client-server computing, currently undergoing final trials, is seen as the key to further development, and this approach to Pathology computing has considerable potential for the future.

Solar Energy Task Force Report: Technical Training Guidelines.

ERIC Educational Resources Information Center

O'Connor, Kevin

This task force report offers guidelines and information for the development of vocational education programs oriented to the commercial application of solar energy in water and space heating. After Section I introduces the Solar Energy Task Force and its activities, Section II outlines the task force's objectives and raises several issues and…

The Flexibility of 12-Month-Olds' Preferences for Phonologically Appropriate Object Labels

ERIC Educational Resources Information Center

MacKenzie, Heather K.; Graham, Susan A.; Curtin, Suzanne; Archer, Stephanie L.

2014-01-01

We explored 12-month-olds' flexibility in accepting phonotactically illegal or ill-formed word forms in a modified associative-learning task. Sixty-four English-learning infants were presented with a training phase that either clarified the purpose of a sound--object association task or left the task ambiguous. Infants were then habituated to sets…

Open angle glaucoma effects on preattentive visual search efficiency for flicker, motion displacement and orientation pop-out tasks.

PubMed

Loughman, James; Davison, Peter; Flitcroft, Ian

2007-11-01

Preattentive visual search (PAVS) describes rapid and efficient retinal and neural processing capable of immediate target detection in the visual field. Damage to the nerve fibre layer or visual pathway might reduce the efficiency with which the visual system performs such analysis. The purpose of this study was to test the hypothesis that patients with glaucoma are impaired on parallel search tasks, and that this would serve to distinguish glaucoma in early cases. Three groups of observers (glaucoma patients, suspect and normal individuals) were examined, using computer-generated flicker, orientation, and vertical motion displacement targets to assess PAVS efficiency. The task required rapid and accurate localisation of a singularity embedded in a field of 119 homogeneous distractors on either the left or right-hand side of a computer monitor. All subjects also completed a choice reaction time (CRT) task. Independent sample T tests revealed PAVS efficiency to be significantly impaired in the glaucoma group compared with both normal and suspect individuals. Performance was impaired in all types of glaucoma tested. Analysis between normal and suspect individuals revealed a significant difference only for motion displacement response times. Similar analysis using a PAVS/CRT index confirmed the glaucoma findings but also showed statistically significant differences between suspect and normal individuals across all target types. A test of PAVS efficiency appears capable of differentiating early glaucoma from both normal and suspect cases. Analysis incorporating a PAVS/CRT index enhances the diagnostic capacity to differentiate normal from suspect cases.

Drops spreading on flexible fibers

NASA Astrophysics Data System (ADS)

Somszor, Katarzyna; Boulogne, François; Sauret, Alban; Dressaire, Emilie; Stone, Howard

2015-11-01

Fibrous media are encountered in many engineered systems such as textile, paper and insulating materials. In most of these materials, fibers are randomly oriented and form a complex network in which drops of wetting liquid tend to accumulate at the nodes of the network. Here we investigate the role of the fiber flexibility on the spreading of a small volume of liquid on a pair of crossed flexible fibers. A drop of silicone oil is dispensed at the point of contact of the fibers and we characterize the liquid morphologies as we vary the volume of liquid, the angle between the fibers, and the length and bending modulus of the fibers. Drop morphologies previously reported for rigid fibers, i.e. a drop, a column and a mixed morphology, are also observed on flexible fibers with modified domains of existence. Moreover, at small inclination angles of the fibers, a new behavior is observed: the fibers bend and collapse. Depending on the volume, the liquid can adopt a column or a mixed morphology on the collapsed fibers. We rationalize our observations with a model based on energetic considerations. Our study suggests that the fiber flexibility adds a rich variety of behaviors that can be crucial for industrial applications.

Flexible spatial perspective-taking: conversational partners weigh multiple cues in collaborative tasks.

PubMed

Galati, Alexia; Avraamides, Marios N

2013-01-01

Research on spatial perspective-taking often focuses on the cognitive processes of isolated individuals as they adopt or maintain imagined perspectives. Collaborative studies of spatial perspective-taking typically examine speakers' linguistic choices, while overlooking their underlying processes and representations. We review evidence from two collaborative experiments that examine the contribution of social and representational cues to spatial perspective choices in both language and the organization of spatial memory. Across experiments, speakers organized their memory representations according to the convergence of various cues. When layouts were randomly configured and did not afford intrinsic cues, speakers encoded their partner's viewpoint in memory, if available, but did not use it as an organizing direction. On the other hand, when the layout afforded an intrinsic structure, speakers organized their spatial memories according to the person-centered perspective reinforced by the layout's structure. Similarly, in descriptions, speakers considered multiple cues whether available a priori or at the interaction. They used partner-centered expressions more frequently (e.g., "to your right") when the partner's viewpoint was misaligned by a small offset or coincided with the layout's structure. Conversely, they used egocentric expressions more frequently when their own viewpoint coincided with the intrinsic structure or when the partner was misaligned by a computationally difficult, oblique offset. Based on these findings we advocate for a framework for flexible perspective-taking: people weigh multiple cues (including social ones) to make attributions about the relative difficulty of perspective-taking for each partner, and adapt behavior to minimize their collective effort. This framework is not specialized for spatial reasoning but instead emerges from the same principles and memory-depended processes that govern perspective-taking in non-spatial tasks.

Designing for flexible interaction between humans and automation: delegation interfaces for supervisory control.

PubMed

Miller, Christopher A; Parasuraman, Raja

2007-02-01

To develop a method enabling human-like, flexible supervisory control via delegation to automation. Real-time supervisory relationships with automation are rarely as flexible as human task delegation to other humans. Flexibility in human-adaptable automation can provide important benefits, including improved situation awareness, more accurate automation usage, more balanced mental workload, increased user acceptance, and improved overall performance. We review problems with static and adaptive (as opposed to "adaptable") automation; contrast these approaches with human-human task delegation, which can mitigate many of the problems; and revise the concept of a "level of automation" as a pattern of task-based roles and authorizations. We argue that delegation requires a shared hierarchical task model between supervisor and subordinates, used to delegate tasks at various levels, and offer instruction on performing them. A prototype implementation called Playbook is described. On the basis of these analyses, we propose methods for supporting human-machine delegation interactions that parallel human-human delegation in important respects. We develop an architecture for machine-based delegation systems based on the metaphor of a sports team's "playbook." Finally, we describe a prototype implementation of this architecture, with an accompanying user interface and usage scenario, for mission planning for uninhabited air vehicles. Delegation offers a viable method for flexible, multilevel human-automation interaction to enhance system performance while maintaining user workload at a manageable level. Most applications of adaptive automation (aviation, air traffic control, robotics, process control, etc.) are potential avenues for the adaptable, delegation approach we advocate. We present an extended example for uninhabited air vehicle mission planning.

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

ERIC Educational Resources Information Center

Kilian, Britta; Hofer, Manfred; Kuhnle, Claudia

2013-01-01

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

Postdictive modulation of visual orientation.

PubMed

Kawabe, Takahiro

2012-01-01

The present study investigated how visual orientation is modulated by subsequent orientation inputs. Observers were presented a near-vertical Gabor patch as a target, followed by a left- or right-tilted second Gabor patch as a distracter in the spatial vicinity of the target. The task of the observers was to judge whether the target was right- or left-tilted (Experiment 1) or whether the target was vertical or not (Supplementary experiment). The judgment was biased toward the orientation of the distracter (the postdictive modulation of visual orientation). The judgment bias peaked when the target and distracter were temporally separated by 100 ms, indicating a specific temporal mechanism for this phenomenon. However, when the visibility of the distracter was reduced via backward masking, the judgment bias disappeared. On the other hand, the low-visibility distracter could still cause a simultaneous orientation contrast, indicating that the distracter orientation is still processed in the visual system (Experiment 2). Our results suggest that the postdictive modulation of visual orientation stems from spatiotemporal integration of visual orientation on the basis of a slow feature matching process.

Distributed Traffic Complexity Management by Preserving Trajectory Flexibility

NASA Technical Reports Server (NTRS)

Idris, Husni; Vivona, Robert A.; Garcia-Chico, Jose-Luis; Wing, David J.

2007-01-01

In order to handle the expected increase in air traffic volume, the next generation air transportation system is moving towards a distributed control architecture, in which groundbased service providers such as controllers and traffic managers and air-based users such as pilots share responsibility for aircraft trajectory generation and management. This paper presents preliminary research investigating a distributed trajectory-oriented approach to manage traffic complexity, based on preserving trajectory flexibility. The underlying hypotheses are that preserving trajectory flexibility autonomously by aircraft naturally achieves the aggregate objective of avoiding excessive traffic complexity, and that trajectory flexibility is increased by collaboratively minimizing trajectory constraints without jeopardizing the intended air traffic management objectives. This paper presents an analytical framework in which flexibility is defined in terms of robustness and adaptability to disturbances and preliminary metrics are proposed that can be used to preserve trajectory flexibility. The hypothesized impacts are illustrated through analyzing a trajectory solution space in a simple scenario with only speed as a degree of freedom, and in constraint situations involving meeting multiple times of arrival and resolving conflicts.

Cardinal rules: Visual orientation perception reflects knowledge of environmental statistics

PubMed Central

Girshick, Ahna R.; Landy, Michael S.; Simoncelli, Eero P.

2011-01-01

Humans are remarkably good at performing visual tasks, but experimental measurements reveal substantial biases in the perception of basic visual attributes. An appealing hypothesis is that these biases arise through a process of statistical inference, in which information from noisy measurements is fused with a probabilistic model of the environment. But such inference is optimal only if the observer’s internal model matches the environment. Here, we provide evidence that this is the case. We measured performance in an orientation-estimation task, demonstrating the well-known fact that orientation judgements are more accurate at cardinal (horizontal and vertical) orientations, along with a new observation that judgements made under conditions of uncertainty are strongly biased toward cardinal orientations. We estimate observers’ internal models for orientation and find that they match the local orientation distribution measured in photographs. We also show how a neural population could embed probabilistic information responsible for such biases. PMID:21642976

Rapid rotational/translational maneuvering experiments of a flexible steel beam

NASA Technical Reports Server (NTRS)

Juang, Jer-Nan; Yang, Li-Farn; Huanag, Jen-Kuang; Macauley, Richard

1989-01-01

Future space manipulators may need translational base motion to expand the access region of a manipulator. An experiment was conducted to demonstrate slewing of flexible structures with coupled rotational and translational axes while simultaneously suppressing vibrational motion during the maneuver. In the experiment, a flexible steel beam carried by a translational cart was maneuvered by an active controller to perform position-control tasks. Experimental results are presented to show how the flexibility of the steel beam influences the multi-input multi-output feedback controller.

Cognitive flexibility predicts early reading skills

PubMed Central

Colé, Pascale; Duncan, Lynne G.; Blaye, Agnès

2014-01-01

An important aspect of learning to read is efficiency in accessing different kinds of linguistic information (orthographic, phonological, and semantic) about written words. The present study investigates whether, in addition to the integrity of such linguistic skills, early progress in reading may require a degree of cognitive flexibility in order to manage the coordination of this information effectively. Our study will look for evidence of a link between flexibility and both word reading and passage reading comprehension, and examine whether any such link involves domain-general or reading-specific flexibility. As the only previous support for a predictive relationship between flexibility and early reading comes from studies of reading comprehension in the opaque English orthography, another possibility is that this relationship may be largely orthography-dependent, only coming into play when mappings between representations are complex and polyvalent. To investigate these questions, 60 second-graders learning to read the more transparent French orthography were presented with two multiple classification tasks involving reading-specific cognitive flexibility (based on words) and non-specific flexibility (based on pictures). Reading skills were assessed by word reading, pseudo-word decoding, and passage reading comprehension measures. Flexibility was found to contribute significant unique variance to passage reading comprehension even in the less opaque French orthography. More interestingly, the data also show that flexibility is critical in accounting for one of the core components of reading comprehension, namely, the reading of words in isolation. Finally, the results constrain the debate over whether flexibility has to be reading-specific to be critically involved in reading. PMID:24966842

Implementation of object-oriented programming in study of electrical race car

NASA Astrophysics Data System (ADS)

Nowak, M.; Baier, M.

2016-08-01

The paper covers issue of conducting advanced research of electrical race car participating in international competition called Sileverline Corporate Challenge. Process of designing race cars in Silesian Greenpower team is aided by a professional engine test stand built particularly in purpose of this research. Phase of testing and simulation is an important part of the implementation of new technologies. Properly developed solutions and test procedures are able to significantly shorten development time and reduce design costs. Testing process must be controlled by a modular and flexible application, easy to modify and ensuring safety. This paper describes the concept of object-oriented programming in LabVIEW and exemplary architecture of object-oriented control application designed to control engine test stand of the electrical race car. Eventually, the task of application will be to steer the electromagnetic brake and the engine load torque to perform according to data from the actual race track. During the designing process of the car, minimizing energy losses and maximizing powertrain efficiency are the main aspects taken into consideration. One of the crucial issues to accomplish these goals is to maintain optimal performance of the motor by applying effective cooling. The paper covers the research verifying the effectiveness of the cooling system.

A shared, flexible neural map architecture reflects capacity limits in both visual short-term memory and enumeration.

PubMed

Knops, André; Piazza, Manuela; Sengupta, Rakesh; Eger, Evelyn; Melcher, David

2014-07-23

Human cognition is characterized by severe capacity limits: we can accurately track, enumerate, or hold in mind only a small number of items at a time. It remains debated whether capacity limitations across tasks are determined by a common system. Here we measure brain activation of adult subjects performing either a visual short-term memory (vSTM) task consisting of holding in mind precise information about the orientation and position of a variable number of items, or an enumeration task consisting of assessing the number of items in those sets. We show that task-specific capacity limits (three to four items in enumeration and two to three in vSTM) are neurally reflected in the activity of the posterior parietal cortex (PPC): an identical set of voxels in this region, commonly activated during the two tasks, changed its overall response profile reflecting task-specific capacity limitations. These results, replicated in a second experiment, were further supported by multivariate pattern analysis in which we could decode the number of items presented over a larger range during enumeration than during vSTM. Finally, we simulated our results with a computational model of PPC using a saliency map architecture in which the level of mutual inhibition between nodes gives rise to capacity limitations and reflects the task-dependent precision with which objects need to be encoded (high precision for vSTM, lower precision for enumeration). Together, our work supports the existence of a common, flexible system underlying capacity limits across tasks in PPC that may take the form of a saliency map. Copyright © 2014 the authors 0270-6474/14/349857-10$15.00/0.

Perceptual learning of basic visual features remains task specific with Training-Plus-Exposure (TPE) training

PubMed Central

Cong, Lin-Juan; Wang, Ru-Jie; Yu, Cong; Zhang, Jun-Yun

2016-01-01

Visual perceptual learning is known to be specific to the trained retinal location, feature, and task. However, location and feature specificity can be eliminated by double-training or TPE training protocols, in which observers receive additional exposure to the transfer location or feature dimension via an irrelevant task besides the primary learning task Here we tested whether these new training protocols could even make learning transfer across different tasks involving discrimination of basic visual features (e.g., orientation and contrast). Observers practiced a near-threshold orientation (or contrast) discrimination task. Following a TPE training protocol, they also received exposure to the transfer task via performing suprathreshold contrast (or orientation) discrimination in alternating blocks of trials in the same sessions. The results showed no evidence for significant learning transfer to the untrained near-threshold contrast (or orientation) discrimination task after discounting the pretest effects and the suprathreshold practice effects. These results thus do not support a hypothetical task-independent component in perceptual learning of basic visual features. They also set the boundary of the new training protocols in their capability to enable learning transfer. PMID:26873777

Cognitive flexibility in drawings of bilingual children.

PubMed

Adi-Japha, Esther; Berberich-Artzi, Jennie; Libnawi, Afaf

2010-01-01

A. Karmiloff-Smith's (1990) task of drawing a nonexistent object is considered to be a measure of cognitive flexibility. The notion of earlier emergence of cognitive flexibility in bilingual children motivated the current researchers to request 4- and 5-year-old English-Hebrew and Arabic-Hebrew bilingual children and their monolingual peers to draw a flower and a house that do not exist (N=80). Bilinguals exhibited a significantly higher rate of interrepresentational flexibility in their drawings (e.g., "a giraffe flower,"a chair-house," found in 28 of 54 drawings), whereas the level of complex intrarepresentational change was similar across groups. Interrepresentational drawings were previously reported only for children older than 7 years. The specific mechanisms by which bilinguals' language experience may lead to interrepresentational flexibility are discussed. © 2010 The Authors. Child Development © 2010 Society for Research in Child Development, Inc.

Flexible muscle modes and synergies in challenging whole-body tasks.

PubMed

Danna-Dos-Santos, Alessander; Degani, Adriana M; Latash, Mark L

2008-08-01

We used the idea of hierarchical control to study multi-muscle synergies during a whole-body sway task performed by a standing person. Within this view, at the lower level of the hierarchy, muscles are united into groups (M-modes). At the higher level, gains at the M-modes are co-varied by the controller in a task-specific way to ensure low variability of important physical variables. In particular, we hypothesized that (1) the composition of M-modes could adjust and (2) an index of M-mode co-variation would become weaker in more challenging conditions. Subjects were required to perform a whole-body sway at 0.5 Hz paced by a metronome. They performed the task with eyes open and closed, while standing on both feet or on one foot only, with and without vibration applied to the Achilles tendons. Integrated indices of muscle activation were subjected to principal component analysis to identify M-modes. An increase in the task complexity led to an increase in the number of principal components that contained significantly loaded indices of muscle activation from 3 to 5. Hence, in more challenging tasks, the controller manipulated a larger number of variables. Multiple regression analysis was used to define the Jacobian of the system mapping small changes in M-mode gains onto shifts of the center of pressure (COP) in the anterior-posterior direction. Further, the variance in the M-mode space across sway cycles was partitioned into two components, one that did not affect an average across cycles COP coordinate and the other that did (good and bad variance, respectively). Under all conditions, the subjects showed substantially more good variance than bad variance interpreted as a multi-M-mode synergy stabilizing the COP trajectory. An index of the strength of the synergy was comparable across all conditions, and there was no modulation of this index over the sway cycle. Hence, our first hypothesis that the composition of M-modes could adjust under challenging conditions

Flexible Muscle Modes and Synergies in Challenging Whole-Body Tasks

PubMed Central

Danna-dos-Santos, Alessander; Degani, Adriana M.; Latash, Mark L.

2008-01-01

We used the idea of hierarchical control to study multi-muscle synergies during a whole-body sway task performed by a standing person. Within this view, at the lower level of the hierarchy, muscles are united into groups (M-modes). At the higher level, gains at the M-modes are co-varied by the controller in a task specific way to ensure low variability of important physical variables. In particular, we hypothesized that (1) the composition of M-modes could adjust and (2) an index of M-mode co-variation would become weaker in more challenging conditions. Subjects were required to perform a whole-body sway at 0.5 Hz paced by a metronome. They performed the task with eyes open and closed, while standing on both feet or on one foot only, with and without vibration applied to the Achilles tendons. Integrated indices of muscle activation were subjected to principal component analysis to identify M-modes. An increase in the task complexity led to an increase in the number of principal components that contained significantly loaded indices of muscle activation from 3 to 5. Hence, in more challenging tasks, the controller manipulated a larger number of variables. Multiple regression analysis was used to define the Jacobian of the system mapping small changes in M-mode gains onto shifts of the center of pressure (COP) in the anterior-posterior direction. Further, the variance in the M-mode space across sway cycles was partitioned into two components, one that did not affect an average across cycles COP coordinate and the other that did (good and bad variance, respectively). Under all conditions, the subjects showed substantially more good variance than bad variance interpreted as a multi-M-mode synergy stabilizing the COP trajectory. An index of the strength of the synergy was comparable across all conditions, and there was no modulation of this index over the sway cycle. Hence, our first hypothesis that the composition of M-modes could adjust under challenging conditions

A Self-Determination Perspective on Chinese Fifth-Graders' Task Disengagement

ERIC Educational Resources Information Center

Zhou, Mingming; Ren, Jing

2017-01-01

Engagement in academic tasks is important. However, compared to the large body of research on task engagement, the number of studies on task disengagement is quite limited. The aim of this study is to examine the associations between the motivational (self-determination) and attitudinal antecedents (learning orientations) of task disengagement.…

Research on optimal path planning algorithm of task-oriented optical remote sensing satellites

NASA Astrophysics Data System (ADS)

Liu, Yunhe; Xu, Shengli; Liu, Fengjing; Yuan, Jingpeng

2015-08-01

GEO task-oriented optical remote sensing satellite, is very suitable for long-term continuous monitoring and quick access to imaging. With the development of high resolution optical payload technology and satellite attitude control technology, GEO optical remote sensing satellites will become an important developing trend for aerospace remote sensing satellite in the near future. In the paper, we focused on GEO optical remote sensing satellite plane array stare imaging characteristics and real-time leading mission of earth observation mode, targeted on satisfying needs of the user with the minimum cost of maneuver, and put forward the optimal path planning algorithm centered on transformation from geographic coordinate space to Field of plane, and finally reduced the burden of the control system. In this algorithm, bounded irregular closed area on the ground would be transformed based on coordinate transformation relations in to the reference plane for field of the satellite payload, and then using the branch and bound method to search for feasible solutions, cutting off the non-feasible solution in the solution space based on pruning strategy; and finally trimming some suboptimal feasible solutions based on the optimization index until a feasible solution for the global optimum. Simulation and visualization presentation software testing results verified the feasibility and effectiveness of the strategy.

Large sexual-orientation-related differences in performance on mental rotation and judgment of line orientation tasks.

PubMed

Rahman, Qazi; Wilson, Glenn D

2003-01-01

This study examined the performance of heterosexual and homosexual men and women on 2 tests of spatial processing, mental rotation (MR) and Benton Judgment of Line Orientation (JLO). The sample comprised 60 heterosexual men, 60 heterosexual women, 60 homosexual men, and 60 homosexual women. There were significant main effects of gender (men achieving higher scores overall) and Gender x Sexual Orientation interactions. Decomposing these interactions revealed large differences between the male groups in favor of heterosexual men on JLO and MR performance. There was a modest difference between the female groups on MR total correct scores in favor of homosexual women but no differences in MR percentage correct. The evidence suggests possible variations in the parietal cortex between homosexual and heterosexual persons.

Trajectory-Oriented Approach to Managing Traffic Complexity: Operational Concept and Preliminary Metrics Definition

NASA Technical Reports Server (NTRS)

Idris, Husni; Vivona, Robert; Garcia-Chico, Jose L.

2008-01-01

This document describes preliminary research on a distributed, trajectory-oriented approach for traffic complexity management. The approach is to manage traffic complexity in a distributed control environment, based on preserving trajectory flexibility and minimizing constraints. In particular, the document presents an analytical framework to study trajectory flexibility and the impact of trajectory constraints on it. The document proposes preliminary flexibility metrics that can be interpreted and measured within the framework.

Personal resources, appraisal, and coping in the adaptation process of immigrants from the Former Soviet Union.

PubMed

Yakhnich, Liat; Ben-Zur, Hasida

2008-04-01

Between 1989 and 2005, Israel absorbed over a million new immigrants, about 90% of whom were from the Former Soviet Union (FSU). The present study investigated the adaptation of these FSU new immigrants in a sample of 301 participants (67% women, ages 25-45 years), who completed inventories measuring personal resources (tolerance of ambiguity and cognitive flexibility), cognitive appraisals (of employment, language, and housing problems), coping strategies, well-being, distress, and willingness to remain in Israel. A structural equation modeling (SEM) analysis showed that tolerance for ambiguity and cognitive flexibility contributed positively to control appraisals, task-oriented coping, and level of participant well-being, and negatively to threat/loss appraisals, emotion/avoidance-oriented coping, and distress. Control appraisals contributed to task-oriented coping, whereas threat/loss appraisals contributed to both emotion/avoidance-oriented and task-oriented coping. Control and challenge appraisals, and task-oriented coping, contributed positively to participant willingness to remain in Israel, whereas emotion/avoidance-oriented coping contributed positively to distress levels, which in turn were negatively related to willingness to remain in Israel. The results of this study have significant implications for such aspects of immigrant adaptation as absorption policies and the provision of individual care by professionals and organizations. Copyright 2008 APA, all rights reserved.

Molecular dynamics simulations on PGLa using NMR orientational constraints.

PubMed

Sternberg, Ulrich; Witter, Raiker

2015-11-01

NMR data obtained by solid state NMR from anisotropic samples are used as orientational constraints in molecular dynamics simulations for determining the structure and dynamics of the PGLa peptide within a membrane environment. For the simulation the recently developed molecular dynamics with orientational constraints technique (MDOC) is used. This method introduces orientation dependent pseudo-forces into the COSMOS-NMR force field. Acting during a molecular dynamics simulation these forces drive molecular rotations, re-orientations and folding in such a way that the motional time-averages of the tensorial NMR properties are consistent with the experimentally measured NMR parameters. This MDOC strategy does not depend on the initial choice of atomic coordinates, and is in principle suitable for any flexible and mobile kind of molecule; and it is of course possible to account for flexible parts of peptides or their side-chains. MDOC has been applied to the antimicrobial peptide PGLa and a related dimer model. With these simulations it was possible to reproduce most NMR parameters within the experimental error bounds. The alignment, conformation and order parameters of the membrane-bound molecule and its dimer were directly derived with MDOC from the NMR data. Furthermore, this new approach yielded for the first time the distribution of segmental orientations with respect to the membrane and the order parameter tensors of the dimer systems. It was demonstrated the deuterium splittings measured at the peptide to lipid ratio of 1/50 are consistent with a membrane spanning orientation of the peptide.

The Influence of Task Involvement on the Use of Learning Strategies.

ERIC Educational Resources Information Center

Nolen, Susan Bobbitt

The relationship between goal orientation and the use of learning strategies and their effects on learning outcomes were investigated. The three goal orientations considered were: (1) task orientation, which involves learning for its own sake; (2) ego orientation, which involves a desire to perform better than others; and (3) work avoidance, which…

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

PubMed

Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

2015-07-01

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

Tactile-Sensing Based on Flexible PVDF Nanofibers via Electrospinning: A Review

PubMed Central

Wang, Xiaomei; Sun, Fazhe; Yin, Guangchao; Wang, Yuting; Liu, Bo

2018-01-01

The flexible tactile sensor has attracted widespread attention because of its great flexibility, high sensitivity, and large workable range. It can be integrated into clothing, electronic skin, or mounted on to human skin. Various nanostructured materials and nanocomposites with high flexibility and electrical performance have been widely utilized as functional materials in flexible tactile sensors. Polymer nanomaterials, representing the most promising materials, especially polyvinylidene fluoride (PVDF), PVDF co-polymer and their nanocomposites with ultra-sensitivity, high deformability, outstanding chemical resistance, high thermal stability and low permittivity, can meet the flexibility requirements for dynamic tactile sensing in wearable electronics. Electrospinning has been recognized as an excellent straightforward and versatile technique for preparing nanofiber materials. This review will present a brief overview of the recent advances in PVDF nanofibers by electrospinning for flexible tactile sensor applications. PVDF, PVDF co-polymers and their nanocomposites have been successfully formed as ultrafine nanofibers, even as randomly oriented PVDF nanofibers by electrospinning. These nanofibers used as the functional layers in flexible tactile sensors have been reviewed briefly in this paper. The β-phase content, which is the strongest polar moment contributing to piezoelectric properties among all the crystalline phases of PVDF, can be improved by adjusting the technical parameters in electrospun PVDF process. The piezoelectric properties and the sensibility for the pressure sensor are improved greatly when the PVDF fibers become more oriented. The tactile performance of PVDF composite nanofibers can be further promoted by doping with nanofillers and nanoclay. Electrospun P(VDF-TrFE) nanofiber mats used for the 3D pressure sensor achieved excellent sensitivity, even at 0.1 Pa. The most significant enhancement is that the aligned electrospun core-shell P

Dissociable Changes of Frontal and Parietal Cortices in Inherent Functional Flexibility across the Human Life Span.

PubMed

Yin, Dazhi; Liu, Wenjing; Zeljic, Kristina; Wang, Zhiwei; Lv, Qian; Fan, Mingxia; Cheng, Wenhong; Wang, Zheng

2016-09-28

Extensive evidence suggests that frontoparietal regions can dynamically update their pattern of functional connectivity, supporting cognitive control and adaptive implementation of task demands. However, it is largely unknown whether this flexibly functional reconfiguration is intrinsic and occurs even in the absence of overt tasks. Based on recent advances in dynamics of resting-state functional resonance imaging (fMRI), we propose a probabilistic framework in which dynamic reconfiguration of intrinsic functional connectivity between each brain region and others can be represented as a probability distribution. A complexity measurement (i.e., entropy) was used to quantify functional flexibility, which characterizes heterogeneous connectivity between a particular region and others over time. Following this framework, we identified both functionally flexible and specialized regions over the human life span (112 healthy subjects from 13 to 76 years old). Across brainwide regions, we found regions showing high flexibility mainly in the higher-order association cortex, such as the lateral prefrontal cortex (LPFC), lateral parietal cortex, and lateral temporal lobules. In contrast, visual, auditory, and sensory areas exhibited low flexibility. Furthermore, we observed that flexibility of the right LPFC improved during maturation and reduced due to normal aging, with the opposite occurring for the left lateral parietal cortex. Our findings reveal dissociable changes of frontal and parietal cortices over the life span in terms of inherent functional flexibility. This study not only provides a new framework to quantify the spatiotemporal behavior of spontaneous brain activity, but also sheds light on the organizational principle behind changes in brain function across the human life span. Recent neuroscientific research has demonstrated that the human capability of adaptive task control is primarily the result of the flexible operation of frontal brain networks. However

The addition of functional task-oriented mental practice to conventional physical therapy improves motor skills in daily functions after stroke.

PubMed

Santos-Couto-Paz, Clarissa C; Teixeira-Salmela, Luci F; Tierra-Criollo, Carlos J

2013-01-01

Mental practice (MP) is a cognitive strategy which may improve the acquisition of motor skills and functional performance of athletes and individuals with neurological injuries. To determine whether an individualized, specific functional task-oriented MP, when added to conventional physical therapy (PT), promoted better learning of motor skills in daily functions in individuals with chronic stroke (13 ± 6.5 months post-stroke). Nine individuals with stable mild and moderate upper limb impairments participated, by employing an A1-B-A2 single-case design. Phases A1 and A2 included one month of conventional PT, and phase B the addition of MP training to PT. The motor activity log (MAL-Brazil) was used to assess the amount of use (AOU) and quality of movement (QOM) of the paretic upper limb; the revised motor imagery questionnaire (MIQ-RS) to assess the abilities in kinesthetic and visual motor imagery; the Minnesota manual dexterity test to assess manual dexterity; and gait speed to assess mobility. After phase A1, no significant changes were observed for any of the outcome measures. However, after phase B, significant improvements were observed for the MAL, AOU and QOM scores (p<0.0001), and MIQ-RS kinesthetic and visual scores (p=0.003; p=0.007, respectively). The significant gains in manual dexterity (p=0.002) and gait speed (p=0.019) were maintained after phase A2. Specific functional task-oriented MP, when added to conventional PT, led to improvements in motor imagery abilities combined with increases in the AOU and QOM in daily functions, manual dexterity, and gait speed.

Flexible spatial perspective-taking: conversational partners weigh multiple cues in collaborative tasks

PubMed Central

Galati, Alexia; Avraamides, Marios N.

2013-01-01

Research on spatial perspective-taking often focuses on the cognitive processes of isolated individuals as they adopt or maintain imagined perspectives. Collaborative studies of spatial perspective-taking typically examine speakers' linguistic choices, while overlooking their underlying processes and representations. We review evidence from two collaborative experiments that examine the contribution of social and representational cues to spatial perspective choices in both language and the organization of spatial memory. Across experiments, speakers organized their memory representations according to the convergence of various cues. When layouts were randomly configured and did not afford intrinsic cues, speakers encoded their partner's viewpoint in memory, if available, but did not use it as an organizing direction. On the other hand, when the layout afforded an intrinsic structure, speakers organized their spatial memories according to the person-centered perspective reinforced by the layout's structure. Similarly, in descriptions, speakers considered multiple cues whether available a priori or at the interaction. They used partner-centered expressions more frequently (e.g., “to your right”) when the partner's viewpoint was misaligned by a small offset or coincided with the layout's structure. Conversely, they used egocentric expressions more frequently when their own viewpoint coincided with the intrinsic structure or when the partner was misaligned by a computationally difficult, oblique offset. Based on these findings we advocate for a framework for flexible perspective-taking: people weigh multiple cues (including social ones) to make attributions about the relative difficulty of perspective-taking for each partner, and adapt behavior to minimize their collective effort. This framework is not specialized for spatial reasoning but instead emerges from the same principles and memory-depended processes that govern perspective-taking in non-spatial tasks

Switch Detection in Preschoolers' Cognitive Flexibility

ERIC Educational Resources Information Center

Chevalier, Nicolas; Wiebe, Sandra A.; Huber, Kristina L.; Espy, Kimberly Andrews

2011-01-01

The current study addressed the role of switch detection in cognitive flexibility by testing the effect of transition cues (i.e., cues that directly signal the need to switch or maintain a given task goal) in a cued set-shifting paradigm at 5 years of age. Children performed better, especially on switch trials, when transition cues were combined…

Task-Oriented Access to Data Files: An Evaluation.

ERIC Educational Resources Information Center

Watters, Carolyn; And Others

1994-01-01

Discussion of information retrieval highlights DalText, a prototype information retrieval system that provides access to nonindexed textual data files where the mode of access is determined by the user based on the task at hand. A user study is described that was conducted at Dalhousie University (Nova Scotia) to test DalText. (Contains 23…

Orientations for the successful categorization of facial expressions and their link with facial features.

PubMed

Duncan, Justin; Gosselin, Frédéric; Cobarro, Charlène; Dugas, Gabrielle; Blais, Caroline; Fiset, Daniel

2017-12-01

Horizontal information was recently suggested to be crucial for face identification. In the present paper, we expand on this finding and investigate the role of orientations for all the basic facial expressions and neutrality. To this end, we developed orientation bubbles to quantify utilization of the orientation spectrum by the visual system in a facial expression categorization task. We first validated the procedure in Experiment 1 with a simple plaid-detection task. In Experiment 2, we used orientation bubbles to reveal the diagnostic-i.e., task relevant-orientations for the basic facial expressions and neutrality. Overall, we found that horizontal information was highly diagnostic for expressions-surprise excepted. We also found that utilization of horizontal information strongly predicted performance level in this task. Despite the recent surge of research on horizontals, the link with local features remains unexplored. We were thus also interested in investigating this link. In Experiment 3, location bubbles were used to reveal the diagnostic features for the basic facial expressions. Crucially, Experiments 2 and 3 were run in parallel on the same participants, in an interleaved fashion. This way, we were able to correlate individual orientation and local diagnostic profiles. Our results indicate that individual differences in horizontal tuning are best predicted by utilization of the eyes.

Changing societies and four tasks of schooling: Challenges for strongly differentiated educational systems

NASA Astrophysics Data System (ADS)

van de Werfhorst, Herman G.

2014-05-01

Changing labour markets, increased calls for selection and excellence, and increased diversity and individualisation have repercussions on how educational systems can prepare youth for work, optimise knowledge production, achieve equality of opportunity, and socialise students into active civic engagement. This paper discusses four central tasks of schooling and examines to what extent societal developments challenge education policy to deliver on the tasks at hand. Particular attention is given to the challenges Europe's strongly diversified educational systems are currently facing. Both the Netherlands and Germany, for example, have been offering vocationally-oriented pathways alongside traditional academic higher education for some time. But today's ongoing changes in job descriptions, mainly due to ever-accelerating technological developments, are causing a risk of skills obsolescence which can only be avoided by continuous upskilling and/or reskilling of a sufficiently flexible workforce. Overcoming differences of intelligence as well as differences of diverse socioeconomic, ethnic and linguistic backgrounds by way of education is another challenge, as is fostering "soft" skills and political awareness. This paper investigates the effectiveness of current education systems in preparing citizens for a functioning modern society.

A user's guide to the Flexible Spacecraft Dynamics and Control Program

NASA Technical Reports Server (NTRS)

Fedor, J. V.

1984-01-01

A guide to the use of the Flexible Spacecraft Dynamics Program (FSD) is presented covering input requirements, control words, orbit generation, spacecraft description and simulation options, and output definition. The program can be used in dynamics and control analysis as well as in orbit support of deployment and control of spacecraft. The program is applicable to inertially oriented spinning, Earth oriented or gravity gradient stabilized spacecraft. Internal and external environmental effects can be simulated.

The flexibility and dynamics of protein disulfide isomerase

PubMed Central

Wells, Stephen A.; Emilio Jimenez‐Roldan, J.; Bhattacharyya, Moitrayee; Vishweshwara, Saraswathi; Freedman, Robert B.

2016-01-01

ABSTRACT We have studied the mobility of the multidomain folding catalyst, protein disulfide isomerase (PDI), by a coarse‐graining approach based on flexibility. We analyze our simulations of yeast PDI (yPDI) using measures of backbone movement, relative positions and orientations of domains, and distances between functional sites. We find that there is interdomain flexibility at every interdomain junction but these show very different characteristics. The extent of interdomain flexibility is such that yPDI's two active sites can approach much more closely than is found in crystal structures—and indeed hinge motion to bring these sites into proximity is the lowest energy normal mode of motion of the protein. The flexibility predicted for yPDI (based on one structure) includes the other known conformation of yPDI and is consistent with (i) the mobility observed experimentally for mammalian PDI and (ii) molecular dynamics. We also observe intradomain flexibility and clear differences between the domains in their propensity for internal motion. Our results suggest that PDI flexibility enables it to interact with many different partner molecules of widely different sizes and shapes, and highlights considerable similarities of yPDI and mammalian PDI. Proteins 2016; 84:1776–1785. © 2016 Wiley Periodicals, Inc. PMID:27616289

Deficits in social cognition and response flexibility in pediatric bipolar disorder.

PubMed

McClure, Erin B; Treland, Julia E; Snow, Joseph; Schmajuk, Mariana; Dickstein, Daniel P; Towbin, Kenneth E; Charney, Dennis S; Pine, Daniel S; Leibenluft, Ellen

2005-09-01

Little is known about neuropsychological and social-cognitive function in patients with pediatric bipolar disorder. Identification of specific deficits and strengths that characterize pediatric bipolar disorder would facilitate advances in diagnosis, treatment, and research on pathophysiology. The purpose of this study was to test the hypothesis that youths with bipolar disorder would perform more poorly than matched healthy comparison subjects on measures of social cognition, motor inhibition, and response flexibility. Forty outpatients with pediatric bipolar disorder and 22 comparison subjects (no differences in age, gender, and IQ) completed measures of social cognition (the pragmatic judgment subtest of the Comprehensive Assessment of Spoken Language, facial expression recognition subtests of the Diagnostic Analysis of Nonverbal Accuracy Scale, the oral expression subtest of the Test of Language Competence), inhibition and response flexibility (stop and stop-change tasks), and motor inhibition (continuous performance tasks). Pediatric bipolar disorder patients performed more poorly than comparison subjects on social-cognitive measures (pragmatic judgment of language, facial expression recognition) and on a task requiring response flexibility. These deficits were present in euthymic patients. Differences between patients and comparison subjects could not be attributed to comorbid attention deficit hyperactivity disorder. Findings of impaired social cognition and response flexibility in youths with pediatric bipolar disorder suggest continuity between pediatric bipolar disorder and adult bipolar disorder. These findings provide a foundation for neurocognitive research designed to identify the neural mechanisms underlying these deficits.

Omnidirectional structured light in a flexible configuration.

PubMed

Paniagua, Carmen; Puig, Luis; Guerrero, José J

2013-10-14

Structured light is a perception method that allows us to obtain 3D information from images of the scene by projecting synthetic features with a light emitter. Traditionally, this method considers a rigid configuration, where the position and orientation of the light emitter with respect to the camera are known and calibrated beforehand. In this paper we propose a new omnidirectional structured light system in flexible configuration, which overcomes the rigidness of the traditional structured light systems. We propose the use of an omnidirectional camera combined with a conic pattern light emitter. Since the light emitter is visible in the omnidirectional image, the computation of its location is possible. With this information and the projected conic in the omnidirectional image, we are able to compute the conic reconstruction, i.e., the 3D information of the conic in the space. This reconstruction considers the recovery of the depth and orientation of the scene surface where the conic pattern is projected. One application of our proposed structured light system in flexible configuration consists of a wearable omnicamera with a low-cost laser in hand for visual impaired personal assistance.

Attention Modifies Spatial Resolution According to Task Demands.

PubMed

Barbot, Antoine; Carrasco, Marisa

2017-03-01

How does visual attention affect spatial resolution? In texture-segmentation tasks, exogenous (involuntary) attention automatically increases resolution at the attended location, which improves performance where resolution is too low (at the periphery) but impairs performance where resolution is already too high (at central locations). Conversely, endogenous (voluntary) attention improves performance at all eccentricities, which suggests a more flexible mechanism. Here, using selective adaptation to spatial frequency, we investigated the mechanism by which endogenous attention benefits performance in resolution tasks. Participants detected a texture target that could appear at several eccentricities. Adapting to high or low spatial frequencies selectively affected performance in a manner consistent with changes in resolution. Moreover, adapting to high, but not low, frequencies mitigated the attentional benefit at central locations where resolution was too high; this shows that attention can improve performance by decreasing resolution. Altogether, our results indicate that endogenous attention benefits performance by modulating the contribution of high-frequency information in order to flexibly adjust spatial resolution according to task demands.

Acute stress impairs cognitive flexibility in men, not women.

PubMed

Shields, Grant S; Trainor, Brian C; Lam, Jovian C W; Yonelinas, Andrew P

2016-09-01

Psychosocial stress influences cognitive abilities, such as long-term memory retrieval. However, less is known about the effects of stress on cognitive flexibility, which is mediated by different neurobiological circuits and could thus be regulated by different neuroendocrine pathways. In this study, we randomly assigned healthy adults to an acute stress induction or control condition and subsequently assessed participants' cognitive flexibility using an open-source version of the Wisconsin Card Sort task. Drawing on work in rodents, we hypothesized that stress would have stronger impairing effects on cognitive flexibility in men than women. As predicted, we found that stress impaired cognitive flexibility in men but did not significantly affect women. Our results thus indicate that stress exerts sex-specific effects on cognitive flexibility in humans and add to the growing body of research highlighting the need to consider sex differences in effects of stress.

Cross-orientation interactions in human vision.

PubMed

Roeber, Urte; Wong, Elaine M Y; Freeman, Alan W

2008-03-18

Humans can discriminate one visual contour from another on the basis of small differences in orientation. This capability depends on cortical detectors that are selective for a small range of orientations. We have measured this orientation bandwidth and the suppression that helps to shape it, with a reverse correlation technique. Human subjects were presented with a stream of randomly oriented gratings at a rate of 30 per second. Their task was to press a key whenever they saw an orientation nominated as the target. We analyzed the data by finding the probability density of two orientations: One preceded the key-press by the reaction time, and the second preceded the first by up to 100 ms. The results were as follows: (1) One grating facilitated the following one in producing a key-press when the gratings differed little in orientation. The estimate of orientation bandwidth resulting from this facilitation was 38 degrees . (2) A large angle between the two orientations reduced the probability of a key-press. This finding was best modelled as a suppression that did not vary with orientation, consistent with the idea that cross-orientation suppression is non-oriented. (3) Analysis of non-consecutive grating pairs showed that cross-orientation interactions lasted no longer than 67 ms.

The Watchdog Task: Concurrent error detection using assertions

NASA Technical Reports Server (NTRS)

Ersoz, A.; Andrews, D. M.; Mccluskey, E. J.

1985-01-01

The Watchdog Task, a software abstraction of the Watchdog-processor, is shown to be a powerful error detection tool with a great deal of flexibility and the advantages of watchdog techniques. A Watchdog Task system in Ada is presented; issues of recovery, latency, efficiency (communication) and preprocessing are discussed. Different applications, one of which is error detection on a single processor, are examined.

Using goal orientations to understand motivation in strength training.

PubMed

Gilson, Todd A; Chow, Graig M; Ewing, Martha E

2008-07-01

Despite the importance that today's athletics place on strength training, research exploring the motivation of athletes in this arena is sparse. It is known that not all athletes will use the same motivational cognitions as inspiration, and these differences can be explored through achievement goal orientations. Through questionnaire data and semistructured interviews, the present study investigated how collegiate athletes maintain high levels of motivation over a period of time during strength training and explored relationships among five goal orientations: task-orientation, self-enhancing ego-orientation, self-defeating ego-orientation, social-approval orientation, and work-avoidance orientation. Subjects (N = 133), comprising 90 men and 43 women, were current varsity collegiate athletes from 15 different sports at a major Midwestern university. In addition, using a screener survey to assess achievement goal orientations, 15 subjects from the sample group who demonstrated a stronger inclination to only one achievement goal orientation were interviewed to gain a more in-depth understanding of their motivation cognitions in strength training. Results showed that the strongest achievement goal orientations reported from all athletes were task-orientation and social-approval. Additionally, five higher-order themes (significant others, improvement, competitive demands, being stronger than others, and miscellaneous) were consistent among the interviewed athletes when describing how they stay motivated during strength training. Whereas all athletes were able to describe at least one motivational strategy they employed during strength training, the dominant achievement goal orientation of some athletes influenced their motivational strategy. By employing the T.A.R.G.E.T. model (), strength coaches can foster adaptive achievement goal orientations and thereby enhance intrinsic motivation for athletes engaging in strength training.

Orienting of attention, pupil size, and the norepinephrine system.

PubMed

Gabay, Shai; Pertzov, Yoni; Henik, Avishai

2011-01-01

This research examined a novel suggestion regarding the involvement of the locus coeruleus-norepinephrine (LC-NE) system in orienting reflexive (exogenous) attention. A common procedure for studying exogenous orienting of attention is Posner's cuing task. Importantly, one can manipulate the required level of target processing by changing task requirements, which, in turn, can elicit a different time course of inhibition of return (IOR). An easy task (responding to target location) produces earlier onset IOR, whereas a demanding task (responding to target identity) produces later onset IOR. Aston-Jones and Cohen (Annual Review of Neuroscience, 28, 403-450, 2005) presented a theory suggesting two different modes of LC activity: tonic and phasic. Accordingly, we suggest that in the more demanding task, the LC-NE system is activated in phasic mode, and in the easier task, it is activated in tonic mode. This, in turn, influences the appearance of IOR. We examined this suggestion by measuring participants' pupil size, which has been demonstrated to correlate with the LC-NE system, while they performed cuing tasks. We found a response-locked phasic dilation of the pupil in the discrimination task, as compared with the localization task, which may reflect different firing modes of the LC-NE system during the two tasks. We also demonstrated a correlation between pupil size at the time of cue presentation and magnitude of IOR.

A Neurobehavioral Model of Flexible Spatial Language Behaviors

PubMed Central

Lipinski, John; Schneegans, Sebastian; Sandamirskaya, Yulia; Spencer, John P.; Schöner, Gregor

2012-01-01

We propose a neural dynamic model that specifies how low-level visual processes can be integrated with higher level cognition to achieve flexible spatial language behaviors. This model uses real-word visual input that is linked to relational spatial descriptions through a neural mechanism for reference frame transformations. We demonstrate that the system can extract spatial relations from visual scenes, select items based on relational spatial descriptions, and perform reference object selection in a single unified architecture. We further show that the performance of the system is consistent with behavioral data in humans by simulating results from 2 independent empirical studies, 1 spatial term rating task and 1 study of reference object selection behavior. The architecture we present thereby achieves a high degree of task flexibility under realistic stimulus conditions. At the same time, it also provides a detailed neural grounding for complex behavioral and cognitive processes. PMID:21517224

Aspects of workplace flexibility and mothers' satisfaction with their husbands' contributions to household labor.

PubMed

Alger, Vanessa M; Crowley, Jocelyn Elise

2012-01-01

This article explores whether mothers’ perceived control over their own workplace flexibility options has any relationship to their satisfaction with their husbands’ contributions to household labor in the United States. We hypothesize that flexibility enhances their ability to more adeptly engage in role management in multiple life areas, thus enabling them to be more satisfied with their partners’ domestic input as well. We use a unique data set of 1,078 randomly sampled women involved in mothers’ organizations that generally attract members based on their current level of participation in the paid labor market. We then link nine distinct workplace flexibility policies with mothers’ satisfaction related to their husbands’ participation in all household tasks, as well as a subset of female-typed tasks. We find that across both arrays of tasks, mothers with more perceived control over work-related schedule predictability and those that had the ability to secure employment again after an extended break had higher levels of satisfaction with their husbands’ participation in household labor. In addition, short-term time off to address unexpected needs was important for all tasks considered together only.

Improving Separation Assurance Stability Through Trajectory Flexibility Preservation

NASA Technical Reports Server (NTRS)

Idris, Husni; Shen, Ni; Wing, David J.

2010-01-01

New information and automation technologies are enabling the distribution of tasks and decisions from the service providers to the users of the air traffic system, with potential capacity and cost benefits. This distribution of tasks and decisions raises the concern that independent user actions will decrease the predictability and increase the complexity of the traffic system, hence inhibiting and possibly reversing any potential benefits. One such concern is the adverse impact of uncoordinated actions by individual aircraft on the stability of separation assurance. For example, individual aircraft performing self-separation may resolve predicted losses of separation or conflicts with some traffic, only to result in secondary conflicts with other traffic or with the same traffic later in time. In answer to this concern, this paper proposes metrics for preserving user trajectory flexibility to be used in self-separation along with other objectives. The hypothesis is that preserving trajectory flexibility will naturally reduce the creation of secondary conflicts by bringing about implicit coordination between aircraft. The impact of using these metrics on improving self-separation stability is investigated by measuring the impact on secondary conflicts. The scenarios analyzed include aircraft in en route airspace with each aircraft meeting a required time of arrival in a twenty minute time horizon while maintaining separation from the surrounding traffic and using trajectory flexibility metrics to mitigate the risk of secondary conflicts. Preliminary experiments showed promising results in that the trajectory flexibility preservation reduced the potential for secondary conflicts.

Visuospatial performance on an internet line judgment task and potential hormonal markers: sex, sexual orientation, and 2D:4D.

PubMed

Collaer, Marcia L; Reimers, Stian; Manning, John T

2007-04-01

We investigated whether performance on a visuospatial line judgment task, the Judgment of Line Angle and Position-15 test (JLAP-15), showed evidence of sensitivity to early sex steroid exposure by examining how it related to sex, as well as to sexual orientation and 2D:4D digit ratios. Participants were drawn from a large Internet study with over 250,000 participants. In the main sample (ages 12-58 years), males outperformed females on the JLAP-15, showing a moderate effect size for sex. In agreement with a prenatal sex hormone hypothesis, line judgment accuracy in adults related to 2D:4D and sexual orientation, both of which are postulated to be influenced by early steroids. In both sexes, better visuospatial performance was associated with lower (more male-typical) digit ratios. For men, heterosexual participants outperformed homosexual/bisexual participants on the JLAP-15 and, for women, homosexual/bisexual participants outperformed heterosexual participants. In children aged 8-10 years, presumed to be a largely prepubertal group, boys also outperformed girls. These findings are consistent with the hypothesis that visuospatial ability is influenced by early sex steroids, although they do not rule out alternative explanations or additional influences. More broadly, such results support a prenatal sex hormone hypothesis that degree of androgen exposure may influence the neural circuitry underlying cognition (visuospatial ability) and sexual orientation as well as aspects of somatic (digit ratio) development.

Switch Detection in Preschoolers’ Cognitive Flexibility

PubMed Central

Chevalier, Nicolas; Wiebe, Sandra A.; Huber, Kristina L.; Espy, Kimberly Andrews

2011-01-01

The present study addressed the role of switch detection in cognitive flexibility by testing the effect of transition cues (i.e., cues that directly signal the need to switch or maintain a given task goal) in a cued set-shifting paradigm at age 5. Children performed better, especially on switch trials, when transition cues were combined with traditional task cues (i.e., cues that directly signal the relevant task on a given trial), relative to conditions without transition cues. This effect was not influenced by explicit knowledge of transition cues or transition cue transparency, suggesting transition cues did not need to be semantically processed to be beneficial. These findings reveal that young children’s difficulties in set-shifting situations partially stem from failures to monitor for the need to switch. PMID:21353678

Behavioral flexibility in an invasive bird is independent of other behaviors

PubMed Central

2016-01-01

Behavioral flexibility is considered important for a species to adapt to environmental change. However, it is unclear how behavioral flexibility works: it relates to problem solving ability and speed in unpredictable ways, which leaves an open question of whether behavioral flexibility varies with differences in other behaviors. If present, such correlations would mask which behavior causes individuals to vary. I investigated whether behavioral flexibility (reversal learning) performances were linked with other behaviors in great-tailed grackles, an invasive bird. I found that behavioral flexibility did not significantly correlate with neophobia, exploration, risk aversion, persistence, or motor diversity. This suggests that great-tailed grackle performance in behavioral flexibility tasks reflects a distinct source of individual variation. Maintaining multiple distinct sources of individual variation, and particularly variation in behavioral flexibility, may be a mechanism for coping with the diversity of novel elements in their environments and facilitate this species’ invasion success. PMID:27478705

Cognition in Orienteering: Theoretical Perspectives and Methods of Study.

ERIC Educational Resources Information Center

Ottosson, Torgny

1996-01-01

Almost without exception, published studies on cognition in orienteering have adopted an information processing perspective involving dualism between objective and subjective worlds. An alternative, experiential framework focuses on the orienteer's conception of (or way of experiencing) the task to be accomplished, and on "affordances" (lines of…

Time limits during visual foraging reveal flexible working memory templates.

PubMed

Kristjánsson, Tómas; Thornton, Ian M; Kristjánsson, Árni

2018-06-01

During difficult foraging tasks, humans rarely switch between target categories, but switch frequently during easier foraging. Does this reflect fundamental limits on visual working memory (VWM) capacity or simply strategic choice due to effort? Our participants performed time-limited or unlimited foraging tasks where they tapped stimuli from 2 target categories while avoiding items from 2 distractor categories. These time limits should have no effect if capacity imposes limits on VWM representations but more flexible VWM could allow observers to use VWM according to task demands in each case. We found that with time limits, participants switched more frequently and switch-costs became much smaller than during unlimited foraging. Observers can therefore switch between complex (conjunction) target categories when needed. We propose that while maintaining many complex templates in working memory is effortful and observers avoid this, they can do so if this fits task demands, showing the flexibility of working memory representations used for visual exploration. This is in contrast with recent proposals, and we discuss the implications of these findings for theoretical accounts of working memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Adaptive Encoding of Outcome Prediction by Prefrontal Cortex Ensembles Supports Behavioral Flexibility.

PubMed

Del Arco, Alberto; Park, Junchol; Wood, Jesse; Kim, Yunbok; Moghaddam, Bita

2017-08-30

The prefrontal cortex (PFC) is thought to play a critical role in behavioral flexibility by monitoring action-outcome contingencies. How PFC ensembles represent shifts in behavior in response to changes in these contingencies remains unclear. We recorded single-unit activity and local field potentials in the dorsomedial PFC (dmPFC) of male rats during a set-shifting task that required them to update their behavior, among competing options, in response to changes in action-outcome contingencies. As behavior was updated, a subset of PFC ensembles encoded the current trial outcome before the outcome was presented. This novel outcome-prediction encoding was absent in a control task, in which actions were rewarded pseudorandomly, indicating that PFC neurons are not merely providing an expectancy signal. In both control and set-shifting tasks, dmPFC neurons displayed postoutcome discrimination activity, indicating that these neurons also monitor whether a behavior is successful in generating rewards. Gamma-power oscillatory activity increased before the outcome in both tasks but did not differentiate between expected outcomes, suggesting that this measure is not related to set-shifting behavior but reflects expectation of an outcome after action execution. These results demonstrate that PFC neurons support flexible rule-based action selection by predicting outcomes that follow a particular action. SIGNIFICANCE STATEMENT Tracking action-outcome contingencies and modifying behavior when those contingencies change is critical to behavioral flexibility. We find that ensembles of dorsomedial prefrontal cortex neurons differentiate between expected outcomes when action-outcome contingencies change. This predictive mode of signaling may be used to promote a new response strategy at the service of behavioral flexibility. Copyright © 2017 the authors 0270-6474/17/378363-11$15.00/0.

Dividing Attention Between Tasks: Testing Whether Explicit Payoff Functions Elicit Optimal Dual-Task Performance.

PubMed

Farmer, George D; Janssen, Christian P; Nguyen, Anh T; Brumby, Duncan P

2018-04-01

We test people's ability to optimize performance across two concurrent tasks. Participants performed a number entry task while controlling a randomly moving cursor with a joystick. Participants received explicit feedback on their performance on these tasks in the form of a single combined score. This payoff function was varied between conditions to change the value of one task relative to the other. We found that participants adapted their strategy for interleaving the two tasks, by varying how long they spent on one task before switching to the other, in order to achieve the near maximum payoff available in each condition. In a second experiment, we show that this behavior is learned quickly (within 2-3 min over several discrete trials) and remained stable for as long as the payoff function did not change. The results of this work show that people are adaptive and flexible in how they prioritize and allocate attention in a dual-task setting. However, it also demonstrates some of the limits regarding people's ability to optimize payoff functions. Copyright © 2017 The Authors. Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

Object orientation affects spatial language comprehension.

PubMed

Burigo, Michele; Sacchi, Simona

2013-01-01

Typical spatial descriptions, such as "The car is in front of the house," describe the position of a located object (LO; e.g., the car) in space relative to a reference object (RO) whose location is known (e.g., the house). The orientation of the RO affects spatial language comprehension via the reference frame selection process. However, the effects of the LO's orientation on spatial language have not received great attention. This study explores whether the pure geometric information of the LO (e.g., its orientation) affects spatial language comprehension using placing and production tasks. Our results suggest that the orientation of the LO influences spatial language comprehension even in the absence of functional relationships. Copyright © 2013 Cognitive Science Society, Inc.

Applied cognitive task analysis (ACTA): a practitioner's toolkit for understanding cognitive task demands.

PubMed

Militello, L G; Hutton, R J

1998-11-01

Cognitive task analysis (CTA) is a set of methods for identifying cognitive skills, or mental demands, needed to perform a task proficiently. The product of the task analysis can be used to inform the design of interfaces and training systems. However, CTA is resource intensive and has previously been of limited use to design practitioners. A streamlined method of CTA, Applied Cognitive Task Analysis (ACTA), is presented in this paper. ACTA consists of three interview methods that help the practitioner to extract information about the cognitive demands and skills required for a task. ACTA also allows the practitioner to represent this information in a format that will translate more directly into applied products, such as improved training scenarios or interface recommendations. This paper will describe the three methods, an evaluation study conducted to assess the usability and usefulness of the methods, and some directions for future research for making cognitive task analysis accessible to practitioners. ACTA techniques were found to be easy to use, flexible, and to provide clear output. The information and training materials developed based on ACTA interviews were found to be accurate and important for training purposes.

Orientation Transfer in Vernier and Stereoacuity Training

PubMed Central

Snell, Nathaniel; Kattner, Florian; Rokers, Bas; Green, C. Shawn

2015-01-01

Human performance on various visual tasks can be improved substantially via training. However, the enhancements are frequently specific to relatively low-level stimulus dimensions. While such specificity has often been thought to be indicative of a low-level neural locus of learning, recent research suggests that these same effects can be accounted for by changes in higher-level areas–in particular in the way higher-level areas read out information from lower-level areas in the service of highly practiced decisions. Here we contrast the degree of orientation transfer seen after training on two different tasks—vernier acuity and stereoacuity. Importantly, while the decision rule that could improve vernier acuity (i.e. a discriminant in the image plane) would not be transferable across orientations, the simplest rule that could be learned to solve the stereoacuity task (i.e. a discriminant in the depth plane) would be insensitive to changes in orientation. Thus, given a read-out hypothesis, more substantial transfer would be expected as a result of stereoacuity than vernier acuity training. To test this prediction, participants were trained (7500 total trials) on either a stereoacuity (N = 9) or vernier acuity (N = 7) task with the stimuli in either a vertical or horizontal configuration (balanced across participants). Following training, transfer to the untrained orientation was assessed. As predicted, evidence for relatively orientation specific learning was observed in vernier trained participants, while no evidence of specificity was observed in stereo trained participants. These results build upon the emerging view that perceptual learning (even very specific learning effects) may reflect changes in inferences made by high-level areas, rather than necessarily fully reflecting changes in the receptive field properties of low-level areas. PMID:26700311

Age Differences in Future Orientation and Delay Discounting

ERIC Educational Resources Information Center

Steinberg, Laurence; Graham, Sandra; O'Brien, Lia; Woolard, Jennifer; Cauffman, Elizabeth; Banich, Marie

2009-01-01

Age differences in future orientation are examined in a sample of 935 individuals between 10 and 30 years using a delay discounting task as well as a new self-report measure. Younger adolescents consistently demonstrate a weaker orientation to the future than do individuals aged 16 and older, as reflected in their greater willingness to accept a…

A focus on polarity: Investigating the role of orientation cues in mediating student performance on mRNA synthesis tasks in an introductory cell and molecular biology course.

PubMed

Olimpo, Jeffrey T; Quijas, Daniel A; Quintana, Anita M

2017-11-01

The central dogma has served as a foundational model for information flow, exchange, and storage in the biological sciences for several decades. Despite its continued importance, however, recent research suggests that novices in the domain possess several misconceptions regarding the aforementioned processes, including those pertaining specifically to the formation of messenger ribonucleic acid (mRNA) transcripts. In the present study, we sought to expand upon these observations through exploration of the influence of orientation cues on students' aptitude at synthesizing mRNAs from provided deoxyribonucleic acid (DNA) template strands. Data indicated that participants (n = 45) were proficient at solving tasks of this nature when the DNA template strand and the mRNA molecule were represented in an antiparallel orientation. In contrast, participants' performance decreased significantly on items in which the mRNA was depicted in a parallel orientation relative to the DNA template strand. Furthermore, participants' Grade Point Average, self-reported confidence in understanding the transcriptional process, and spatial ability were found to mediate their performance on the mRNA synthesis tasks. Collectively, these data reaffirm the need for future research and pedagogical interventions designed to enhance students' comprehension of the central dogma in a manner that makes transparent its relevance to real-world scientific phenomena. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(6):501-508, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

Task-dependent vestibular feedback responses in reaching.

PubMed

Keyser, Johannes; Medendorp, W Pieter; Selen, Luc P J

2017-07-01

When reaching for an earth-fixed object during self-rotation, the motor system should appropriately integrate vestibular signals and sensory predictions to compensate for the intervening motion and its induced inertial forces. While it is well established that this integration occurs rapidly, it is unknown whether vestibular feedback is specifically processed dependent on the behavioral goal. Here, we studied whether vestibular signals evoke fixed responses with the aim to preserve the hand trajectory in space or are processed more flexibly, correcting trajectories only in task-relevant spatial dimensions. We used galvanic vestibular stimulation to perturb reaching movements toward a narrow or a wide target. Results show that the same vestibular stimulation led to smaller trajectory corrections to the wide than the narrow target. We interpret this reduced compensation as a task-dependent modulation of vestibular feedback responses, tuned to minimally intervene with the task-irrelevant dimension of the reach. These task-dependent vestibular feedback corrections are in accordance with a central prediction of optimal feedback control theory and mirror the sophistication seen in feedback responses to mechanical and visual perturbations of the upper limb. NEW & NOTEWORTHY Correcting limb movements for external perturbations is a hallmark of flexible sensorimotor behavior. While visual and mechanical perturbations are corrected in a task-dependent manner, it is unclear whether a vestibular perturbation, naturally arising when the body moves, is selectively processed in reach control. We show, using galvanic vestibular stimulation, that reach corrections to vestibular perturbations are task dependent, consistent with a prediction of optimal feedback control theory. Copyright © 2017 the American Physiological Society.

Choice of Grating Orientation for Evaluation of Peripheral Vision.

PubMed

Venkataraman, Abinaya Priya; Winter, Simon; Rosén, Robert; Lundström, Linda

2016-06-01

Peripheral resolution acuity depends on the orientation of the stimuli. However, it is uncertain if such a meridional effect also exists for peripheral detection tasks because they are affected by optical errors. Knowledge of the quantitative differences in acuity for different grating orientations is crucial for choosing the appropriate stimuli for evaluations of peripheral resolution and detection tasks. We assessed resolution and detection thresholds for different grating orientations in the peripheral visual field. Resolution and detection thresholds were evaluated for gratings of four different orientations in eight different visual field meridians in the 20-deg visual field in white light. Detection measurements in monochromatic light (543 nm; bandwidth, 10 nm) were also performed to evaluate the effects of chromatic aberration on the meridional effect. A combination of trial lenses and adaptive optics system was used to correct the monochromatic lower- and higher-order aberrations. For both resolution and detection tasks, gratings parallel to the visual field meridian had better threshold compared with the perpendicular gratings, whereas the two oblique gratings had similar thresholds. The parallel and perpendicular grating acuity differences for resolution and detection tasks were 0.16 logMAR and 0.11 logMAD, respectively. Elimination of chromatic errors did not affect the meridional preference in detection acuity. Similar to peripheral resolution, detection also shows a meridional effect that appears to have a neural origin. The threshold difference seen for parallel and perpendicular gratings suggests the use of two oblique gratings as stimuli in alternative forced-choice procedures for peripheral vision evaluation to reduce measurement variation.

Effect of tDCS on task relevant and irrelevant perceptual learning of complex objects.

PubMed

Van Meel, Chayenne; Daniels, Nicky; de Beeck, Hans Op; Baeck, Annelies

2016-01-01

During perceptual learning the visual representations in the brain are altered, but these changes' causal role has not yet been fully characterized. We used transcranial direct current stimulation (tDCS) to investigate the role of higher visual regions in lateral occipital cortex (LO) in perceptual learning with complex objects. We also investigated whether object learning is dependent on the relevance of the objects for the learning task. Participants were trained in two tasks: object recognition using a backward masking paradigm and an orientation judgment task. During both tasks, an object with a red line on top of it were presented in each trial. The crucial difference between both tasks was the relevance of the object: the object was relevant for the object recognition task, but not for the orientation judgment task. During training, half of the participants received anodal tDCS stimulation targeted at the lateral occipital cortex (LO). Afterwards, participants were tested on how well they recognized the trained objects, the irrelevant objects presented during the orientation judgment task and a set of completely new objects. Participants stimulated with tDCS during training showed larger improvements of performance compared to participants in the sham condition. No learning effect was found for the objects presented during the orientation judgment task. To conclude, this study suggests a causal role of LO in relevant object learning, but given the rather low spatial resolution of tDCS, more research on the specificity of this effect is needed. Further, mere exposure is not sufficient to train object recognition in our paradigm.

Communicative Task-Based Learning: What Does It Resolve?

ERIC Educational Resources Information Center

Bruton, Anthony

A discussion of communicative task-based second language learning looks at what differentiates a number of related classroom approaches: (1) two orientations, one focusing on learning-to-communicate and the other on communicating-to-learn; (2) emphasis on input, reception, and analysis in contrast to emphasis on communicative tasks; (3)…

Engineering of oriented carbon nanotubes in composite materials

PubMed Central

Beigmoradi, Razieh; Mohebbi-Kalhori, Davod

2018-01-01

The orientation and arrangement engineering of carbon nanotubes (CNTs) in composite structures is considered a challenging issue. In this regard, two groups of in situ and ex situ techniques have been developed. In the first, the arrangement is achieved during CNT growth, while in the latter, the CNTs are initially grown in random orientation and the arrangement is then achieved during the device integration process. As the ex situ techniques are free from growth restrictions and more flexible in terms of controlling the alignment and sorting of the CNTs, they are considered by some as the preferred technique for engineering of oriented CNTs. This review focuses on recent progress in the improvement of the orientation and alignment of CNTs in composite materials. Moreover, the advantages and disadvantages of the processes are discussed as well as their future outlook. PMID:29515955

Developing a Very Low Vision Orientation and Mobility Test Battery (O&M-VLV).

PubMed

Finger, Robert P; Ayton, Lauren N; Deverell, Lil; O'Hare, Fleur; McSweeney, Shane C; Luu, Chi D; Fenwick, Eva K; Keeffe, Jill E; Guymer, Robyn H; Bentley, Sharon A

2016-09-01

This study aimed to determine the feasibility of an assessment of vision-related orientation and mobility (O&M) tasks in persons with severe vision loss. These tasks may be used for future low vision rehabilitation clinical assessments or as outcome measures in vision restoration trials. Forty legally blind persons (mean visual acuity logMAR 2.3, or hand movements) with advanced retinitis pigmentosa participated in the Orientation & Mobility-Very Low Vision (O&M-VLV) subtests from the Low Vision Assessment of Daily Activities (LoVADA) protocol. Four categories of tasks were evaluated: route travel in three indoor hospital environments, a room orientation task (the "cafe"), a visual exploration task (the "gallery"), and a modified version of the Timed Up and Go (TUG) test, which assesses re-orientation and route travel. Spatial cognition was assessed using the Stuart Tactile Maps test. Visual acuity and visual fields were measured. A generalized linear regression model showed that a number of measures in the O&M-VLV tasks were related to residual visual function. The percentage of preferred walking speed without an aid on three travel routes was associated with visual field (p < 0.01 for all routes) whereas the number of contacts with obstacles during route travel was associated with acuity (p = 0.001). TUG-LV task time was associated with acuity (p = 0.003), as was the cafe time and distance traveled (p = 0.006 and p < 0.001, respectively). The gallery score was the only measure that was significantly associated with both residual acuity and fields (p < 0.001 and p = 0.001, respectively). The O&M-VLV was designed to capture key elements of O&M performance in persons with severe vision loss, which is a population not often studied previously. Performance on these tasks was associated with both binocular visual acuity and visual field. This new protocol includes assessments of orientation, which may be of benefit in vision restoration clinical trials.

Resident designed intern orientation to address the new ACGME Common Program Requirements for resident supervision.

PubMed

Rialon, Kristy L; Barfield, Michael E; Elfenbein, Dawn M; Lunsford, Keri E; Tracy, Elisabeth T; Migaly, John

2013-01-01

To design an orientation for surgical interns to meet the new Accreditation Council for Graduate Medical Education Common Program Requirements regarding supervision, to test patient-management competencies, and to assess confidence on skills and tasks pre-orientation and post-orientation. Twenty-seven incoming surgical interns participated in a two-day orientation to clinical duties. Activities included a pre-test, lectures, simulation, oral examination, intern shadowing, and a post-test. Incoming interns were surveyed before and after orientation and two months later for confidence in patient-management and surgical intern skills. Paired t-tests were used to determine if confidence improved pre-orientation and post-orientation, and two months following orientation. The study took place at an academic training hospital. All (n = 27) postgraduate year-1 (PGY-1) surgical residents at our institution, which included the categorical and nondesignated preliminary general surgery, urology, orthopedic surgery, otolaryngology, and neurosurgery programs. All interns passed the oral and written examinations, and were deemed able to be indirectly supervised, with direct supervision immediately available. They reported increased confidence in all areas of patient management addressed during orientation, and this confidence was retained after two months. In surgical and floor-related tasks and skills, interns reported no increase in confidence directly following orientation. However, after two months, they reported a significant increase in confidence, particularly in those tasks that are performed often. New requirements for resident supervision require creative ways of verifying resident competency in basic skills. This type of orientation is an effective way to address the new requirements of supervision and teach interns the tasks and skills that are necessary for internship. Copyright © 2013 Association of Program Directors in Surgery. Published by Elsevier Inc. All

Flexibility as a management principle in dementia care: the Adards example.

PubMed

Cohen-Mansfield, Jiska; Bester, Allan

2006-08-01

Flexibility is an essential ingredient of person-centered care. We illustrate the potential impact of flexibility by portraying a nursing home that uses flexibility in its approach to residents and staff members. The paper describes the management strategies, principles, and environmental features used by the Adards nursing home in Australia. Adards' flexibility in daily work and task scheduling promotes both resident and staff autonomy, which in turn allows for higher staffing levels, lower staff turnover, and more typical life experiences for residents than is found in many long-term-care facilities in the United States. The article provides an example and a basis for future discussion on this topic, with the hope that it will prompt other institutions to expand the level of flexibility in their policies and procedures.

Improving the human readability of Arden Syntax medical logic modules using a concept-oriented terminology and object-oriented programming expressions.

PubMed

Choi, Jeeyae; Bakken, Suzanne; Lussier, Yves A; Mendonça, Eneida A

2006-01-01

Medical logic modules are a procedural representation for sharing task-specific knowledge for decision support systems. Based on the premise that clinicians may perceive object-oriented expressions as easier to read than procedural rules in Arden Syntax-based medical logic modules, we developed a method for improving the readability of medical logic modules. Two approaches were applied: exploiting the concept-oriented features of the Medical Entities Dictionary and building an executable Java program to replace Arden Syntax procedural expressions. The usability evaluation showed that 66% of participants successfully mapped all Arden Syntax rules to Java methods. These findings suggest that these approaches can play an essential role in the creation of human readable medical logic modules and can potentially increase the number of clinical experts who are able to participate in the creation of medical logic modules. Although our approaches are broadly applicable, we specifically discuss the relevance to concept-oriented nursing terminologies and automated processing of task-specific nursing knowledge.

Orienting in Virtual Environments: How Are Surface Features and Environmental Geometry Weighted in an Orientation Task?

ERIC Educational Resources Information Center

Kelly, Debbie M.; Bischof, Walter F.

2008-01-01

We investigated how human adults orient in enclosed virtual environments, when discrete landmark information is not available and participants have to rely on geometric and featural information on the environmental surfaces. In contrast to earlier studies, where, for women, the featural information from discrete landmarks overshadowed the encoding…

Electrophysiological evidence for flexible goal-directed cue processing during episodic retrieval

PubMed Central

Herron, Jane E.; Evans, Lisa H.; Wilding, Edward L.

2016-01-01

A widely held assumption is that memory retrieval is aided by cognitive control processes that are engaged flexibly in service of memory retrieval and memory decisions. While there is some empirical support for this view, a notable exception is the absence of evidence for the flexible use of retrieval control in functional neuroimaging experiments requiring frequent switches between tasks with different cognitive demands. This absence is troublesome in so far as frequent switches between tasks mimic some of the challenges that are typically placed on memory outside the laboratory. In this experiment we instructed participants to alternate frequently between three episodic memory tasks requiring item recognition or retrieval of one of two different kinds of contextual information encoded in a prior study phase (screen location or encoding task). Event-related potentials (ERPs) elicited by unstudied items in the two tasks requiring retrieval of study context were reliably different, demonstrating for the first time that ERPs index task-specific processing of retrieval cues when retrieval goals change frequently. The inclusion of the item recognition task was a novel and important addition in this study, because only the ERPs elicited by unstudied items in one of the two context conditions diverged from those in the item recognition condition. This outcome constrains functional interpretations of the differences that emerged between the two context conditions and emphasises the utility of this baseline in functional imaging studies of retrieval processing operations. PMID:26892854

Aspects on Teaching/Learning with Object Oriented Programming for Entry Level Courses of Engineering.

ERIC Educational Resources Information Center

de Oliveira, Clara Amelia; Conte, Marcos Fernando; Riso, Bernardo Goncalves

This work presents a proposal for Teaching/Learning, on Object Oriented Programming for Entry Level Courses of Engineering and Computer Science, on University. The philosophy of Object Oriented Programming comes as a new pattern of solution for problems, where flexibility and reusability appears over the simple data structure and sequential…

Self-handicapping prior to academic-oriented tasks in children with attention deficit/hyperactivity disorder (ADHD): medication effects and comparisons with controls.

PubMed

Waschbusch, Daniel A; Craig, Rebecca; Pelham, William E; King, Sara

2007-04-01

Examined self-handicapping prior to academic-oriented tasks in children with and without ADHD and examined whether stimulant medication influenced self-handicapping. Participants were 61 children ages 6 to 13, including 22 children with ADHD tested after taking a placebo, 21 children with ADHD tested after taking stimulant medication, and 18 non-ADHD controls. Participants completed three measures of self handicapping and also completed self-evaluations of their performance. Results showed greater self handicapping and more positive self-evaluations in children with ADHD than in controls regardless of medication condition. Findings suggest children with ADHD may use self handicapping to ameliorate the effects of experiencing high rates of academic failure.

Gender differences in global-local perception? Evidence from orientation and shape judgments.

PubMed

Kimchi, Ruth; Amishav, Rama; Sulitzeanu-Kenan, Anat

2009-01-01

Direct examinations of gender differences in global-local processing are sparse, and the results are inconsistent. We examined this issue with a visuospatial judgment task and with a shape judgment task. Women and men were presented with hierarchical stimuli that varied in closure (open or closed shape) or in line orientation (oblique or horizontal/vertical) at the global or local level. The task was to classify the stimuli on the basis of the variation at the global level (global classification) or at the local level (local classification). Women's classification by closure (global or local) was more accurate than men's for stimuli that varied in closure on both levels, suggesting a female advantage in discriminating shape properties. No gender differences were observed in global-local processing bias. Women and men exhibited a global advantage, and they did not differ in their speed of global or local classification, with only one exception. Women were slower than men in local classification by orientation when the to-be-classified lines were embedded in a global line with a different orientation. This finding suggests that women are more distracted than men by misleading global oriented context when performing local orientation judgments, perhaps because women and men differ in their ability to use cognitive schemes to compensate for the distracting effects of the global context. Our findings further suggest that whether or not gender differences arise depends not only on the nature of the visual task but also on the visual context.

About turn: how object orientation affects categorisation and mental rotation.

PubMed

Milivojevic, Branka; Hamm, Jeff P; Corballis, Michael C

2011-11-01

High-density ERPs evoked by rotated alphanumeric characters were examined to determine how neural processing is affected by stimulus orientation during letter/digit classifications and during mirror/normal discriminations. The former task typically produces response times that are unaffected by stimulus orientation while the latter is thought to require mental rotation. Sensitivity to orientation was first observed around 100-140 ms and this effect was attributed to differences in low-level features between vertical and oblique orientations. Subsequently, character misorientation amplified the N170, a neural marker of object classification, between 160 and 220 ms. Top-down processing is reflected in the ERPs beginning at 280-320 ms and this time range may reflect binding of ventral and dorsal stream information. In the case of mirror-normal discrimination these top-down processes can lead to mental rotation between 340 and 700 ms. Therefore, although neural processing reflects object orientation, these effects do not translate into increases in reaction-times or impaired accuracy for categorisation, and precede those that do in the mental-rotation task. Copyright © 2011 Elsevier Ltd. All rights reserved.

Relationship between Running Speed and Cognitive Processes in Orienteering: Two Empirical Studies.

ERIC Educational Resources Information Center

Cheshikhina, Valentina V.

1993-01-01

Fourteen qualified orienteers completed a stepwise increased treadmill velocity test in which controls had to be transferred from a master map. Orienteering accuracy was greatest at the anaerobic threshold speed. In a second study, 17 orienteers performed arithmetic tasks before and after a treadmill workout. Performance was significantly better…

Task decomposition for a multilimbed robot to work in reachable but unorientable space

NASA Technical Reports Server (NTRS)

Su, Chau; Zheng, Yuan F.

1991-01-01

Robot manipulators installed on legged mobile platforms are suggested for enlarging robot workspace. To plan the motion of such a system, the arm-platform motion coordination problem is raised, and a task decomposition is proposed to solve the problem. A given task described by the destination position and orientation of the end effector is decomposed into subtasks for arm manipulation and for platform configuration, respectively. The former is defined as the end-effector position and orientation with respect to the platform, and the latter as the platform position and orientation in the base coordinates. Three approaches are proposed for the task decomposition. The approaches are also evaluated in terms of the displacements, from which an optimal approach can be selected.

The development of consistency and flexibility in manual pointing during middle childhood.

PubMed

Golenia, Laura; Schoemaker, Marina M; Otten, Egbert; Tuitert, Inge; Bongers, Raoul M

2018-05-21

Goal-directed actions become truly functional and skilled when they are consistent yet flexible. In manual pointing, end-effector consistency is characterized by the end position of the index fingertip, whereas flexibility in movement execution is captured by the use of abundant arm-joint configurations not affecting the index finger end position. Because adults have been shown to exploit their system's flexibility in challenging conditions, we wondered whether during middle childhood children are already able to exploit motor flexibility when demanded by the situation. We had children aged 5-10 years and adults perform pointing movements in a nonchallenging and challenging condition. Results showed that end-effector errors and flexibility in movement execution decreased with age. Importantly, only the 9-10-year-olds and adults showed increased flexibility in the challenging condition. Thus, while consistency increases and flexibility decreases during mid-childhood development, from the age of nine children appear able to employ more flexibility with increasing task demands. © 2018 Wiley Periodicals, Inc.

Age-differences in cognitive flexibility when overcoming a preexisting bias through feedback.

PubMed

Wilson, Cristina G; Nusbaum, Amy T; Whitney, Paul; Hinson, John M

2018-08-01

Older adults are often worse than younger adults at adapting to changing situational demands, and this difference is commonly attributed to an age-related decline in acquiring and updating information. Previous research on aging and cognitive flexibility has used measures that require adapting to novel associations learned during a laboratory task (e.g., choice X led to positive outcomes but now leads to negative outcomes). However, in everyday life people must frequently overcome associations based on preexisting beliefs and biases (e.g., you like to eat cake, but your doctor said to limit your sugar intake). The goal of the present study was to examine possible age-differences in overcoming a preexisting bias and determine whether age-related changes in the acquisition and updating of information influence this form of flexibility. Older (n = 20) and younger (n = 20) adults completed a novel task in which repeated choices were made between a sure option (gain or loss) and one of two risky options that were initially ambiguous. Optimal performance required overcoming a framing bias toward being risk seeking to avoid a sure loss and risk averse when offered a sure gain. Probe questions assessed knowledge of choice outcomes, while skin conductance assessed physiological reactions to choices and choice outcomes. Both older and younger adults demonstrated flexibility by reducing the impact of bias over trials, but younger adults had better performance overall. Age-differences were associated with distinct aspects of processing. Young adults had more precise knowledge of choice outcomes and developed skin conductance responses in anticipation of bad choices that were not apparent in older adults. Older adults showed significant improvement over trials in their ability to decrease bias-driven choices, but younger showed greater flexibility. Age-differences in task performance were based on differences in learning and corresponding representations of task

Substrate Structures For Growth Of Highly Oriented And/Or Epitaxial Layers Thereon

DOEpatents

Arendt, Paul N.; Foltyn, Stephen R.; Groves, James R.; Jia, Quanxi

2005-07-26

A composite substrate structure including a substrate, a layer of a crystalline metal oxide or crystalline metal oxynitride material upon the substrate, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the crystalline metal oxide or crystalline metal oxynitride material layer is provided together with additional layers such as one or more layers of a buffer material upon the oriented cubic oxide material layer. Jc's of 2.3×106 A/cm2 have been demonstrated with projected Ic's of 320 Amperes across a sample 1 cm wide for a superconducting article including a flexible polycrystalline metallic substrate, an inert oxide material layer upon the surface of the flexible polycrystalline metallic substrate, a layer of a crystalline metal oxide or crystalline metal oxynitride material upon the layer of the inert oxide material, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the crystalline metal oxide or crystalline metal oxynitride material layer, a layer of a buffer material upon the oriented cubic oxide material layer, and, a top-layer of a high temperature superconducting material upon the layer of a buffer material.

Navigation system for flexible endoscopes

NASA Astrophysics Data System (ADS)

Hummel, Johann; Figl, Michael; Birkfellner, Wolfgang; Häfner, Michael; Kollmann, Christian; Bergmann, Helmar

2003-05-01

Endoscopic Ultrasound (EUS) features flexible endoscopes equipped with a radial or linear array scanhead allowing high resolution examination of organs adjacent to the upper gastrointestinal tract. An optical system based on fibre-glass or a CCD-chip allows additional orientation. However, 3-dimensional orientation and correct identification of the various anatomical structures may be difficult. It therefore seems desirable to merge real-time US images with high resolution CT or MR images acquired prior to EUS to simplify navigation during the intervention. The additional information provided by CT or MR images might facilitate diagnosis of tumors and, ultimately, guided puncture of suspicious lesions. We built a grid with 15 plastic spheres and measured their positions relatively to five fiducial markers placed on the top of the grid. For this measurement we used an optical tracking system (OTS) (Polaris, NDI, Can). Two sensors of an electromagnetic tracking system (EMTS) (Aurora, NDI, Can) were mounted on a flexible endoscope (Pentax GG 38 UX, USA) to enable a free hand ultrasound calibration. To determine the position of the plastic spheres in the emitter coordinate system of the EMTS we applied a point-to-point registration (Horn) using the coordinates of the fiducial markers in both coordinate systems (OTS and EMTS). For the transformation between EMTS to the CT space the Horn algorithm was adopted again using the fiducial markers. Visualization was enabled by the use of the AVW-4.0 library (Biomedical Imaging Resource, Mayo Clinic, Rochester/MN, USA). To evaluate the suitability of our new navigation system we measured the Fiducial Registration Error (FRE) of the diverse registrations and the Target Registration Error (TRE) for the complete transformation from the US space to the CT space. The FRE for the ultrasound calibration amounted to 4.3 mm +/- 4.2 mm, resulting from 10 calibration procedures. For the transformation from the OTS reference system to the

Attention Modifies Spatial Resolution According to Task Demands

PubMed Central

Barbot, Antoine; Carrasco, Marisa

2017-01-01

How does visual attention affect spatial resolution? In texture-segmentation tasks, exogenous (involuntary) attention automatically increases resolution at the attended location, which improves performance where resolution is too low (at the periphery) but impairs performance where resolution is already too high (at central locations). Conversely, endogenous (voluntary) attention improves performance at all eccentricities, which suggests a more flexible mechanism. Here, using selective adaptation to spatial frequency, we investigated the mechanism by which endogenous attention benefits performance in resolution tasks. Participants detected a texture target that could appear at several eccentricities. Adapting to high or low spatial frequencies selectively affected performance in a manner consistent with changes in resolution. Moreover, adapting to high, but not low, frequencies mitigated the attentional benefit at central locations where resolution was too high; this shows that attention can improve performance by decreasing resolution. Altogether, our results indicate that endogenous attention benefits performance by modulating the contribution of high-frequency information in order to flexibly adjust spatial resolution according to task demands. PMID:28118103

Exploring Learning-Oriented Assessment Processes

ERIC Educational Resources Information Center

Carless, David

2015-01-01

This paper proposes a model of learning-oriented assessment to inform assessment theory and practice. The model focuses on three interrelated processes: the assessment tasks which students undertake; students' development of self-evaluative capacities; and student engagement with feedback. These three strands are explored through the analysis of…

Evidence of common and separate eye and hand accumulators underlying flexible eye-hand coordination

PubMed Central

Jana, Sumitash; Gopal, Atul

2016-01-01

Eye and hand movements are initiated by anatomically separate regions in the brain, and yet these movements can be flexibly coupled and decoupled, depending on the need. The computational architecture that enables this flexible coupling of independent effectors is not understood. Here, we studied the computational architecture that enables flexible eye-hand coordination using a drift diffusion framework, which predicts that the variability of the reaction time (RT) distribution scales with its mean. We show that a common stochastic accumulator to threshold, followed by a noisy effector-dependent delay, explains eye-hand RT distributions and their correlation in a visual search task that required decision-making, while an interactive eye and hand accumulator model did not. In contrast, in an eye-hand dual task, an interactive model better predicted the observed correlations and RT distributions than a common accumulator model. Notably, these two models could only be distinguished on the basis of the variability and not the means of the predicted RT distributions. Additionally, signatures of separate initiation signals were also observed in a small fraction of trials in the visual search task, implying that these distinct computational architectures were not a manifestation of the task design per se. Taken together, our results suggest two unique computational architectures for eye-hand coordination, with task context biasing the brain toward instantiating one of the two architectures. NEW & NOTEWORTHY Previous studies on eye-hand coordination have considered mainly the means of eye and hand reaction time (RT) distributions. Here, we leverage the approximately linear relationship between the mean and standard deviation of RT distributions, as predicted by the drift-diffusion model, to propose the existence of two distinct computational architectures underlying coordinated eye-hand movements. These architectures, for the first time, provide a computational basis for

Visual spatial cue use for guiding orientation in two-to-three-year-old children

PubMed Central

van den Brink, Danielle; Janzen, Gabriele

2013-01-01

In spatial development representations of the environment and the use of spatial cues change over time. To date, the influence of individual differences in skills relevant for orientation and navigation has not received much attention. The current study investigated orientation abilities on the basis of visual spatial cues in 2–3-year-old children, and assessed factors that possibly influence spatial task performance. Thirty-month and 35-month-olds performed an on-screen Virtual Reality (VR) orientation task searching for an animated target in the presence of visual self-movement cues and landmark information. Results show that, in contrast to 30-month-old children, 35-month-olds were successful in using visual spatial cues for maintaining orientation. Neither age group benefited from landmarks present in the environment, suggesting that successful task performance relied on the use of optic flow cues, rather than object-to-object relations. Analysis of individual differences revealed that 2-year-olds who were relatively more independent in comparison to their peers, as measured by the daily living skills scale of the parental questionnaire Vineland-Screener were most successful at the orientation task. These results support previous findings indicating that the use of various spatial cues gradually improves during early childhood. Our data show that a developmental transition in spatial cue use can be witnessed within a relatively short period of 5 months only. Furthermore, this study indicates that rather than chronological age, individual differences may play a role in successful use of visual cues for spatial updating in an orientation task. Future studies are necessary to assess the exact nature of these individual differences. PMID:24368903

Visual spatial cue use for guiding orientation in two-to-three-year-old children.

PubMed

van den Brink, Danielle; Janzen, Gabriele

2013-01-01

In spatial development representations of the environment and the use of spatial cues change over time. To date, the influence of individual differences in skills relevant for orientation and navigation has not received much attention. The current study investigated orientation abilities on the basis of visual spatial cues in 2-3-year-old children, and assessed factors that possibly influence spatial task performance. Thirty-month and 35-month-olds performed an on-screen Virtual Reality (VR) orientation task searching for an animated target in the presence of visual self-movement cues and landmark information. Results show that, in contrast to 30-month-old children, 35-month-olds were successful in using visual spatial cues for maintaining orientation. Neither age group benefited from landmarks present in the environment, suggesting that successful task performance relied on the use of optic flow cues, rather than object-to-object relations. Analysis of individual differences revealed that 2-year-olds who were relatively more independent in comparison to their peers, as measured by the daily living skills scale of the parental questionnaire Vineland-Screener were most successful at the orientation task. These results support previous findings indicating that the use of various spatial cues gradually improves during early childhood. Our data show that a developmental transition in spatial cue use can be witnessed within a relatively short period of 5 months only. Furthermore, this study indicates that rather than chronological age, individual differences may play a role in successful use of visual cues for spatial updating in an orientation task. Future studies are necessary to assess the exact nature of these individual differences.

Dopamine treatment and cognitive functioning in individuals with Parkinson's disease: the "cognitive flexibility" hypothesis seems to work.

PubMed

Costa, Alberto; Peppe, Antonella; Mazzù, Ilenia; Longarzo, Mariachiara; Caltagirone, Carlo; Carlesimo, Giovanni A

2014-01-01

Previous data suggest that (i) dopamine modulates the ability to implement nonroutine schemata and update operations (flexibility processes) and that (ii) dopamine-related improvement may be related to baseline dopamine levels in target pathways (inverted U-shaped hypothesis). To investigate above hypotheses in individuals with Parkinson's disease (PD). Twenty PD patients were administered tasks varying as to flexibility load in two treatment conditions: (i) "off" condition, about 18 hours after dopamine dose and (ii) "on" condition, after dopamine administration. PD patients were separated into two groups: low performers (i.e., performance on Digit Span Backward below the sample mean) and high performers (i.e., performance above the mean). Twenty healthy individuals performed the tasks in two sessions without taking drugs. Passing from the "off" to the "on" state, only low performer PD patients significantly improved their performance on high-flexibility measures (interference condition of the Stroop test; P < 0.05); no significant effect was found on low-flexibility tasks. These findings document that high-flexibility processes are sensitive to dopamine neuromodulation in the early phases of PD. This is in line with the hypothesis that striatal dopamine pathways, affected early by PD, are precociously implicated in the expression of cognitive disorders in these individuals.

Stable and variable affordances are both automatic and flexible

PubMed Central

Borghi, Anna M.; Riggio, Lucia

2015-01-01

The mere observation of pictures or words referring to manipulable objects is sufficient to evoke their affordances since objects and their nouns elicit components of appropriate motor programs associated with object interaction. While nobody doubts that objects actually evoke motor information, the degree of automaticity of this activation has been recently disputed. Recent evidence has indeed revealed that affordances activation is flexibly modulated by the task and by the physical and social context. It is therefore crucial to understand whether these results challenge previous evidence showing that motor information is activated independently from the task. The context and the task can indeed act as an early or late filter. We will review recent data consistent with the notion that objects automatically elicit multiple affordances and that top-down processes select among them probably inhibiting motor information that is not consistent with behavior goals. We will therefore argue that automaticity and flexibility of affordances are not in conflict. We will also discuss how language can incorporate affordances showing similarities, but also differences, between the motor information elicited by vision and language. Finally we will show how the distinction between stable and variable affordances can accommodate all these effects. PMID:26150778

Analysis of Trajectory Flexibility Preservation Impact on Traffic Complexity

NASA Technical Reports Server (NTRS)

Idris, Husni; El-Wakil, Tarek; Wing, David J.

2009-01-01

The growing demand for air travel is increasing the need for mitigation of air traffic congestion and complexity problems, which are already at high levels. At the same time new information and automation technologies are enabling the distribution of tasks and decisions from the service providers to the users of the air traffic system, with potential capacity and cost benefits. This distribution of tasks and decisions raises the concern that independent user actions will decrease the predictability and increase the complexity of the traffic system, hence inhibiting and possibly reversing any potential benefits. In answer to this concern, the authors proposed the introduction of decision-making metrics for preserving user trajectory flexibility. The hypothesis is that such metrics will make user actions naturally mitigate traffic complexity. In this paper, the impact of using these metrics on traffic complexity is investigated. The scenarios analyzed include aircraft in en route airspace with each aircraft meeting a required time of arrival in a one-hour time horizon while mitigating the risk of loss of separation with the other aircraft, thus preserving its trajectory flexibility. The experiments showed promising results in that the individual trajectory flexibility preservation induced self-separation and self-organization effects in the overall traffic situation. The effects were quantified using traffic complexity metrics, namely dynamic density indicators, which indicated that using the flexibility metrics reduced aircraft density and the potential of loss of separation.

How performance-contingent reward prospect modulates cognitive control: Increased cue maintenance at the cost of decreased flexibility.

PubMed

Hefer, Carmen; Dreisbach, Gesine

2017-10-01

Growing evidence suggests that reward prospect promotes cognitive stability in terms of increased context or cue maintenance. In 3 Experiments, using different versions of the AX-continuous performance task, we investigated whether this reward effect comes at the cost of decreased cognitive flexibility. Experiment 1 shows that the reward induced increase of cue maintenance perseverates even when reward is no longer available. Experiment 2 shows that this reward effect not only survives the withdrawal of reward but also delays the adaptation to changed task conditions that make cue usage maladaptive. And finally in Experiment 3, it is shown that this reduced flexibility to adapt is observed in a more demanding modified version of the AX-continuous performance task and is even stronger under conditions of sustained reward. Taken together, all 3 Experiments thus speak to the idea that the prospect of reward increases cue maintenance and thereby cognitive stability. This increased cognitive stability however comes at the cost of decreased flexibility in terms of delayed adaptation to new reward and task conditions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Enhancing Problem-Solving Capabilities Using Object-Oriented Programming Language

ERIC Educational Resources Information Center

Unuakhalu, Mike F.

2009-01-01

This study integrated object-oriented programming instruction with transfer training activities in everyday tasks, which might provide a mechanism that can be used for efficient problem solving. Specifically, a Visual BASIC embedded with everyday tasks group was compared to another group exposed to Visual BASIC instruction only. Subjects were 40…

Tracking changing environments: innovators are fast, but not flexible learners.

PubMed

Griffin, Andrea S; Guez, David; Lermite, Françoise; Patience, Madeleine

2013-01-01

Behavioural innovations are increasingly thought to provide a rich source of phenotypic plasticity and evolutionary change. Innovation propensity shows substantial variation across avian taxa and provides an adaptive mechanism by which behaviour is flexibly adjusted to changing environmental conditions. Here, we tested for the first time the prediction that inter-individual variation in innovation propensity is equally a measure of behavioural flexibility. We used Indian mynas, Sturnus tristis, a highly successful worldwide invader. Results revealed that mynas that solved an extractive foraging task more quickly learnt to discriminate between a cue that predicted food, and one that did not more quickly. However, fast innovators were slower to change their behaviour when the significance of the food cues changed. This unexpected finding appears at odds with the well-established view that avian taxa with larger brains relative to their body size, and therefore greater neural processing power, are both faster, and more flexible learners. We speculate that the existence of this relationship across taxa can be reconciled with its absence within species by assuming that fast, innovative learners and non innovative, slow, flexible learners constitute two separate individual strategies, which are both underpinned by enhanced neural processing power. This idea is consistent with the recent proposal that individuals may differ consistently in 'cognitive style', differentially trading off speed against accuracy in cognitive tasks.

Evaluation of a novel flexible snake robot for endoluminal surgery.

PubMed

Patel, Nisha; Seneci, Carlo A; Shang, Jianzhong; Leibrandt, Konrad; Yang, Guang-Zhong; Darzi, Ara; Teare, Julian

2015-11-01

Endoluminal therapeutic procedures such as endoscopic submucosal dissection are increasingly attractive given the shift in surgical paradigm towards minimally invasive surgery. This novel three-channel articulated robot was developed to overcome the limitations of the flexible endoscope which poses a number of challenges to endoluminal surgery. The device enables enhanced movement in a restricted workspace, with improved range of motion and with the accuracy required for endoluminal surgery. To evaluate a novel flexible robot for therapeutic endoluminal surgery. Bench-top studies. Research laboratory. Targeting and navigation tasks of the robot were performed to explore the range of motion and retroflexion capabilities. Complex endoluminal tasks such as endoscopic mucosal resection were also simulated. Successful completion, accuracy and time to perform the bench-top tasks were the main outcome measures. The robot ranges of movement, retroflexion and navigation capabilities were demonstrated. The device showed significantly greater accuracy of targeting in a retroflexed position compared to a conventional endoscope. Bench-top study and small study sample. We were able to demonstrate a number of simulated endoscopy tasks such as navigation, targeting, snaring and retroflexion. The improved accuracy of targeting whilst in a difficult configuration is extremely promising and may facilitate endoluminal surgery which has been notoriously challenging with a conventional endoscope.

Choice of Grating Orientation for Evaluation of Peripheral Vision

PubMed Central

Venkataraman, Abinaya Priya; Winter, Simon; Rosén, Robert; Lundström, Linda

2016-01-01

ABSTRACT Purpose Peripheral resolution acuity depends on the orientation of the stimuli. However, it is uncertain if such a meridional effect also exists for peripheral detection tasks because they are affected by optical errors. Knowledge of the quantitative differences in acuity for different grating orientations is crucial for choosing the appropriate stimuli for evaluations of peripheral resolution and detection tasks. We assessed resolution and detection thresholds for different grating orientations in the peripheral visual field. Methods Resolution and detection thresholds were evaluated for gratings of four different orientations in eight different visual field meridians in the 20-deg visual field in white light. Detection measurements in monochromatic light (543 nm; bandwidth, 10 nm) were also performed to evaluate the effects of chromatic aberration on the meridional effect. A combination of trial lenses and adaptive optics system was used to correct the monochromatic lower- and higher-order aberrations. Results For both resolution and detection tasks, gratings parallel to the visual field meridian had better threshold compared with the perpendicular gratings, whereas the two oblique gratings had similar thresholds. The parallel and perpendicular grating acuity differences for resolution and detection tasks were 0.16 logMAR and 0.11 logMAD, respectively. Elimination of chromatic errors did not affect the meridional preference in detection acuity. Conclusions Similar to peripheral resolution, detection also shows a meridional effect that appears to have a neural origin. The threshold difference seen for parallel and perpendicular gratings suggests the use of two oblique gratings as stimuli in alternative forced-choice procedures for peripheral vision evaluation to reduce measurement variation. PMID:26889822

Fatigue modulates dopamine availability and promotes flexible choice reversals during decision making.

PubMed

Iodice, Pierpaolo; Ferrante, Claudio; Brunetti, Luigi; Cabib, Simona; Protasi, Feliciano; Walton, Mark E; Pezzulo, Giovanni

2017-04-03

During decisions, animals balance goal achievement and effort management. Despite physical exercise and fatigue significantly affecting the levels of effort that an animal exerts to obtain a reward, their role in effort-based choice and the underlying neurochemistry are incompletely known. In particular, it is unclear whether fatigue influences decision (cost-benefit) strategies flexibly or only post-decision action execution and learning. To answer this question, we trained mice on a T-maze task in which they chose between a high-cost, high-reward arm (HR), which included a barrier, and a low-cost, low-reward arm (LR), with no barrier. The animals were parametrically fatigued immediately before the behavioural tasks by running on a treadmill. We report a sharp choice reversal, from the HR to LR arm, at 80% of their peak workload (PW), which was temporary and specific, as the mice returned to choose the HC when the animals were successively tested at 60% PW or in a two-barrier task. These rapid reversals are signatures of flexible choice. We also observed increased subcortical dopamine levels in fatigued mice: a marker of individual bias to use model-based control in humans. Our results indicate that fatigue levels can be incorporated in flexible cost-benefits computations that improve foraging efficiency.

The analysis and large-angle control of a flexible beam using an adaptive truss

NASA Technical Reports Server (NTRS)

Warrington, Thomas J.; Clark, William W.; Robertshaw, Harry H.; Horner, C. Garnett

1991-01-01

This preliminary study of an adaptive truss slewing problem investigates the static positioning of an adaptive truss at slewed orientations and the dynamic vibrations of an attached flexible beam. A nonlinear model of an adaptive truss and flexible beam is derived. Linear control laws are developed and simulated for various truss configurations. Results show the linear control laws developed at a slewed configuration perform best at that configuration.

Validating the Electric Maze Task as a Measure of Planning

ERIC Educational Resources Information Center

Sheppard, Kelly W.; Cheatham, Carol L.

2017-01-01

The Electric Maze Task (EMT) is a novel planning task designed to allow flexible testing of planning abilities across a broad age range and to incorporate manipulations to test underlying planning abilities, such as working-memory and inhibitory control skills. The EMT was tested in a group of 63 typically developing 7- to 12-year-olds.…

About Turn: How Object Orientation Affects Categorisation and Mental Rotation

ERIC Educational Resources Information Center

Milivojevic, Branka; Hamm, Jeff P.; Corballis, Michael C.

2011-01-01

High-density ERPs evoked by rotated alphanumeric characters were examined to determine how neural processing is affected by stimulus orientation during letter/digit classifications and during mirror/normal discriminations. The former task typically produces response times that are unaffected by stimulus orientation while the latter is thought to…

W-band PELDOR with 1 kW microwave power: molecular geometry, flexibility and exchange coupling.

PubMed

Reginsson, Gunnar W; Hunter, Robert I; Cruickshank, Paul A S; Bolton, David R; Sigurdsson, Snorri Th; Smith, Graham M; Schiemann, Olav

2012-03-01

A technique that is increasingly being used to determine the structure and conformational flexibility of biomacromolecules is Pulsed Electron-Electron Double Resonance (PELDOR or DEER), an Electron Paramagnetic Resonance (EPR) based technique. At X-band frequencies (9.5 GHz), PELDOR is capable of precisely measuring distances in the range of 1.5-8 nm between paramagnetic centres but the orientation selectivity is weak. In contrast, working at higher frequencies increases the orientation selection but usually at the expense of decreased microwave power and PELDOR modulation depth. Here it is shown that a home-built high-power pulsed W-band EPR spectrometer (HiPER) with a large instantaneous bandwidth enables one to achieve PELDOR data with a high degree of orientation selectivity and large modulation depths. We demonstrate a measurement methodology that gives a set of PELDOR time traces that yield highly constrained data sets. Simulating the resulting time traces provides a deeper insight into the conformational flexibility and exchange coupling of three bisnitroxide model systems. These measurements provide strong evidence that W-band PELDOR may prove to be an accurate and quantitative tool in assessing the relative orientations of nitroxide spin labels and to correlate those orientations to the underlying biological structure and dynamics. Copyright © 2012 Elsevier Inc. All rights reserved.

The interaction of feature and space based orienting within the attention set.

PubMed

Lim, Ahnate; Sinnett, Scott

2014-01-01

The processing of sensory information relies on interacting mechanisms of sustained attention and attentional capture, both of which operate in space and on object features. While evidence indicates that exogenous attentional capture, a mechanism previously understood to be automatic, can be eliminated while concurrently performing a demanding task, we reframe this phenomenon within the theoretical framework of the "attention set" (Most et al., 2005). Consequently, the specific prediction that cuing effects should reappear when feature dimensions of the cue overlap with those in the attention set (i.e., elements of the demanding task) was empirically tested and confirmed using a dual-task paradigm involving both sustained attention and attentional capture, adapted from Santangelo et al. (2007). Participants were required to either detect a centrally presented target presented in a stream of distractors (the primary task), or respond to a spatially cued target (the secondary task). Importantly, the spatial cue could either share features with the target in the centrally presented primary task, or not share any features. Overall, the findings supported the attention set hypothesis showing that a spatial cuing effect was only observed when the peripheral cue shared a feature with objects that were already in the attention set (i.e., the primary task). However, this finding was accompanied by differential attentional orienting dependent on the different types of objects within the attention set, with feature-based orienting occurring for target-related objects, and additional spatial-based orienting for distractor-related objects.

The interaction of feature and space based orienting within the attention set

PubMed Central

Lim, Ahnate; Sinnett, Scott

2014-01-01

The processing of sensory information relies on interacting mechanisms of sustained attention and attentional capture, both of which operate in space and on object features. While evidence indicates that exogenous attentional capture, a mechanism previously understood to be automatic, can be eliminated while concurrently performing a demanding task, we reframe this phenomenon within the theoretical framework of the “attention set” (Most et al., 2005). Consequently, the specific prediction that cuing effects should reappear when feature dimensions of the cue overlap with those in the attention set (i.e., elements of the demanding task) was empirically tested and confirmed using a dual-task paradigm involving both sustained attention and attentional capture, adapted from Santangelo et al. (2007). Participants were required to either detect a centrally presented target presented in a stream of distractors (the primary task), or respond to a spatially cued target (the secondary task). Importantly, the spatial cue could either share features with the target in the centrally presented primary task, or not share any features. Overall, the findings supported the attention set hypothesis showing that a spatial cuing effect was only observed when the peripheral cue shared a feature with objects that were already in the attention set (i.e., the primary task). However, this finding was accompanied by differential attentional orienting dependent on the different types of objects within the attention set, with feature-based orienting occurring for target-related objects, and additional spatial-based orienting for distractor-related objects. PMID:24523682

Novel metamaterial based antennas for flexible wireless systems

NASA Astrophysics Data System (ADS)