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Sample records for additional cognitive load

  1. Robust Multimodal Cognitive Load Measurement

    DTIC Science & Technology

    2014-03-26

    dimension, Hurst exponent ) of electroencephalogram (EEG) signals to evaluate changes in working memory load during the performance of a cognitive task...dimension, Hurst exponent ) of electroencephalogram (EEG) signals to evaluate changes in working memory load during the performance of a cognitive task with...approximate entropies, wavelet-based complexity measures, correlation dimension, Hurst exponent ) of electroencephalogram (EEG) signals to evaluate changes

  2. Cognitive Load Theory: How Many Types of Load Does It Really Need?

    ERIC Educational Resources Information Center

    Kalyuga, Slava

    2011-01-01

    Cognitive load theory has been traditionally described as involving three separate and additive types of load. Germane load is considered as a learning-relevant load complementing extraneous and intrinsic load. This article argues that, in its traditional treatment, germane load is essentially indistinguishable from intrinsic load, and therefore…

  3. Neuroimaging of Cognitive Load in Instructional Multimedia

    ERIC Educational Resources Information Center

    Whelan, Robert R.

    2007-01-01

    This paper reviews research literature on cognitive load measurement in learning and neuroimaging, and describes a mapping between the main elements of cognitive load theory and findings in functional neuroanatomy. It is argued that these findings may lead to the improved measurement of cognitive load using neuroimaging. The paper describes how…

  4. Effects of Cognitive Load on Trust

    DTIC Science & Technology

    2013-10-01

    27 5. Operational Processes ...the person’s benevolence. 3.1. Cognitive Load and Trust Cognitive load is a key component of the four-stage model of human information processing ...capacity of working memory and processing of novel information (Baddeley, 2003; Paas et al., 2003). It is clear that, like trust, cognitive load plays

  5. Emotion Unchained: Facial Expression Modulates Gaze Cueing under Cognitive Load

    PubMed Central

    Petrucci, Manuel

    2016-01-01

    Direction of eye gaze cues spatial attention, and typically this cueing effect is not modulated by the expression of a face unless top-down processes are explicitly or implicitly involved. To investigate the role of cognitive control on gaze cueing by emotional faces, participants performed a gaze cueing task with happy, angry, or neutral faces under high (i.e., counting backward by 7) or low cognitive load (i.e., counting forward by 2). Results show that high cognitive load enhances gaze cueing effects for angry facial expressions. In addition, cognitive load reduces gaze cueing for neutral faces, whereas happy facial expressions and gaze affected object preferences regardless of load. This evidence clearly indicates a differential role of cognitive control in processing gaze direction and facial expression, suggesting that under typical conditions, when we shift attention based on social cues from another person, cognitive control processes are used to reduce interference from emotional information. PMID:27959925

  6. Robust Multimodal Cognitive Load Measurement II

    DTIC Science & Technology

    2015-06-24

    and GSR values. 15. SUBJECT TERMS Behavioural Science, Cognitive Psychology 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...Final 3. DATES COVERED (From - To) 26 June 2014 – 25 June 2015 4. TITLE AND SUBTITLE (134144) Robust Multimodal Cognitive Load...research accomplishments out of the Robust Multimodal Cognitive Load Measurement II (RMCLM) project in the past one-year period. The objective of this

  7. Automatic Multimodal Cognitive Load Measurement (AMCLM)

    DTIC Science & Technology

    2011-06-01

    Schmutz, P., Heinz, S., et al.,. 2009. Cognitive load in ecommerce applications: measurement and effects on user satisfaction. Adv. in Hum.-Comp...interpret the cognitive processes through their effect on the operator’s body state. In the past, physiological measures usually entailed invasive equipment...sensing. As a physiological index, eye activity has been considered as an effective indicator of cognitive workload assessment, as it can be sensitive

  8. Adverse cognitive effects of antiepileptic pharmacotherapy: Each additional drug matters.

    PubMed

    Witt, Juri-Alexander; Elger, Christian E; Helmstaedter, Christoph

    2015-11-01

    The study was set up to evaluate the impact of the total drug load of antiepileptic pharmacotherapy on cognition. Retrospective analyses were based on 834 patients with epilepsy who underwent a brief routine assessment of executive function and verbal memory (EpiTrack Plus) at our department. The total drug load was quantified in two ways: (1) number of concurrent antiepileptic drugs (AEDs) and (2) total drug load according to the defined daily dose (DDD) provided by the World Health Organization. The cognitive measures showed higher inverse correlations with the number of AEDs (executive function: r=-0.35, p<0.001; memory: r=-0.22, p<0.001) than with the total DDD (executive function: r=-0.27, p<0.001; memory: r=-0.17, p<0.001). Reanalysis with statistical control for disease severity hardly changed the aforementioned results. With each additional drug in polytherapy, we observed a significantly lower performance in executive function. In this regard an additional explorative approach revealed that regimens combining AEDs with favorable cognitive profiles were associated with higher cognitive performance. Correlations between indicators of disease severity and drug load indices were low: altogether explaining only up to 9% of the observed variance in drug load. The findings demonstrate a considerable adverse effect of a higher drug load on cognition, especially on executive functions. Simply counting the number of drugs may be sufficient as a rough estimate of the risk of side effects. However, the combination of AEDs with favorable cognitive profiles may attenuate the negative effect of the total drug load.

  9. Using Electroencephalography to Measure Cognitive Load

    ERIC Educational Resources Information Center

    Antonenko, Pavlo; Paas, Fred; Grabner, Roland; van Gog, Tamara

    2010-01-01

    Application of physiological methods, in particular electroencephalography (EEG), offers new and promising approaches to educational psychology research. EEG is identified as a physiological index that can serve as an online, continuous measure of cognitive load detecting subtle fluctuations in instantaneous load, which can help explain effects of…

  10. Element Interactivity and Intrinsic, Extraneous, and Germane Cognitive Load

    ERIC Educational Resources Information Center

    Sweller, John

    2010-01-01

    In cognitive load theory, element interactivity has been used as the basic, defining mechanism of intrinsic cognitive load for many years. In this article, it is suggested that element interactivity underlies extraneous cognitive load as well. By defining extraneous cognitive load in terms of element interactivity, a distinct relation between…

  11. Respiratory Changes in Response to Cognitive Load: A Systematic Review

    PubMed Central

    Grassmann, Mariel; Vlemincx, Elke; von Leupoldt, Andreas; Mittelstädt, Justin M.

    2016-01-01

    When people focus attention or carry out a demanding task, their breathing changes. But which parameters of respiration vary exactly and can respiration reliably be used as an index of cognitive load? These questions are addressed in the present systematic review of empirical studies investigating respiratory behavior in response to cognitive load. Most reviewed studies were restricted to time and volume parameters while less established, yet meaningful parameters such as respiratory variability have rarely been investigated. The available results show that respiratory behavior generally reflects cognitive processing and that distinct parameters differ in sensitivity: While mentally demanding episodes are clearly marked by faster breathing and higher minute ventilation, respiratory amplitude appears to remain rather stable. The present findings further indicate that total variability in respiratory rate is not systematically affected by cognitive load whereas the correlated fraction decreases. In addition, we found that cognitive load may lead to overbreathing as indicated by decreased end-tidal CO2 but is also accompanied by elevated oxygen consumption and CO2 release. However, additional research is needed to validate the findings on respiratory variability and gas exchange measures. We conclude by outlining recommendations for future research to increase the current understanding of respiration under cognitive load. PMID:27403347

  12. Spectral EEG features for evaluating cognitive load.

    PubMed

    Zarjam, Pega; Epps, Julien; Chen, Fang

    2011-01-01

    This study was undertaken to investigate spectral features derived from EEG signals for measuring cognitive load. Measurements of this kind have important commercial and clinical applications for optimizing the performance of users working under high mental load conditions, or as cognitive tests. Based on EEG recordings for a reading task in which three different levels of cognitive load were induced, it is shown that a set of spectral features--the spectral entropy, weighted mean frequency and its bandwidth, and spectral edge frequency--are all able to discriminate the three load levels effectively. An interesting result is that spectral entropy, which reflects the distribution of spectral energy rather than its magnitude, provides very good discrimination between cognitive load levels. We also report those EEG channels for which statistical significance between load levels was achieved. The effect of frequency bands on the spectral features is also investigated here. The results indicate that the choice of optimal frequency band can be dependent on the spectral feature extracted.

  13. Interactive Distance Education: A Cognitive Load Perspective

    ERIC Educational Resources Information Center

    Kalyuga, Slava

    2012-01-01

    Evidence-based approaches to the design of the next generation of interactive distance education need to take into account established multimedia learning principles. Cognitive load theory is a theory that has significantly contributed to the development of such principles. It has applied our knowledge of major features and processing limitations…

  14. Effects of Cognitive Load on Speech Recognition

    ERIC Educational Resources Information Center

    Mattys, Sven L.; Wiget, Lukas

    2011-01-01

    The effect of cognitive load (CL) on speech recognition has received little attention despite the prevalence of CL in everyday life, e.g., dual-tasking. To assess the effect of CL on the interaction between lexically-mediated and acoustically-mediated processes, we measured the magnitude of the "Ganong effect" (i.e., lexical bias on phoneme…

  15. Performance of a cognitive load inventory during simulated handoffs: Evidence for validity

    PubMed Central

    Young, John Q; Boscardin, Christy K; van Dijk, Savannah M; Abdullah, Ruqayyah; Irby, David M; Sewell, Justin L; Ten Cate, Olle; O’Sullivan, Patricia S

    2016-01-01

    Background: Advancing patient safety during handoffs remains a public health priority. The application of cognitive load theory offers promise, but is currently limited by the inability to measure cognitive load types. Objective: To develop and collect validity evidence for a revised self-report inventory that measures cognitive load types during a handoff. Methods: Based on prior published work, input from experts in cognitive load theory and handoffs, and a think-aloud exercise with residents, a revised Cognitive Load Inventory for Handoffs was developed. The Cognitive Load Inventory for Handoffs has items for intrinsic, extraneous, and germane load. Students who were second- and sixth-year students recruited from a Dutch medical school participated in four simulated handoffs (two simple and two complex cases). At the end of each handoff, study participants completed the Cognitive Load Inventory for Handoffs, Paas’ Cognitive Load Scale, and one global rating item for intrinsic load, extraneous load, and germane load, respectively. Factor and correlational analyses were performed to collect evidence for validity. Results: Confirmatory factor analysis yielded a single factor that combined intrinsic and germane loads. The extraneous load items performed poorly and were removed from the model. The score from the combined intrinsic and germane load items associated, as predicted by cognitive load theory, with a commonly used measure of overall cognitive load (Pearson’s r = 0.83, p < 0.001), case complexity (beta = 0.74, p < 0.001), level of experience (beta = −0.96, p < 0.001), and handoff accuracy (r = −0.34, p < 0.001). Conclusion: These results offer encouragement that intrinsic load during handoffs may be measured via a self-report measure. Additional work is required to develop an adequate measure of extraneous load. PMID:28348737

  16. Cognitive Load Theory: New Conceptualizations, Specifications, and Integrated Research Perspectives

    ERIC Educational Resources Information Center

    Paas, Fred; van Gog, Tamara; Sweller, John

    2010-01-01

    Over the last few years, cognitive load theory has progressed and advanced rapidly. The articles in this special issue, which document those advances, are based on contributions to the 3rd International Cognitive Load Theory Conference (2009), Heerlen, The Netherlands. The articles of this special issue on cognitive load theory discuss new…

  17. Effects of Cognitive Load on Trust

    DTIC Science & Technology

    2012-05-01

    Cognitive  Load on Trust” project in conjunction with the US AFRL and  Sunway   University , Malaysia.  NICTA’s role comprised the measurement and assessment...Cognitive  Load  on  Trust”  project  in  conjunction  with  the  US  AFRL  and  Sunway   University , Malaysia. NICTA’s role comprised the measurement...international research effort in  collaboration with Dr. Lyons  and Dr. Stokes  (AFRL),  and Dr. Yeo  ( University  of Malaysia  Sarawak), with separate proposals

  18. Blur Detection is Unaffected by Cognitive Load

    PubMed Central

    Loschky, Lester C.; Ringer, Ryan V.; Johnson, Aaron P.; Larson, Adam M.; Neider, Mark; Kramer, Arthur F.

    2014-01-01

    Blur detection is affected by retinal eccentricity, but is it also affected by attentional resources? Research showing effects of selective attention on acuity and contrast sensitivity suggests that allocating attention should increase blur detection. However, research showing that blur affects selection of saccade targets suggests that blur detection may be pre-attentive. To investigate this question, we carried out experiments in which viewers detected blur in real-world scenes under varying levels of cognitive load manipulated by the N-back task. We used adaptive threshold estimation to measure blur detection thresholds at 0°, 3°, 6°, and 9° eccentricity. Participants carried out blur detection as a single task, a single task with to-be-ignored letters, or an N-back task with four levels of cognitive load (0, 1, 2, or 3-back). In Experiment 1, blur was presented gaze-contingently for occasional single eye fixations while participants viewed scenes in preparation for an easy picture recognition memory task, and the N-back stimuli were presented auditorily. The results for three participants showed a large effect of retinal eccentricity on blur thresholds, significant effects of N-back level on N-back performance, scene recognition memory, and gaze dispersion, but no effect of N-back level on blur thresholds. In Experiment 2, we replicated Experiment 1 but presented the images tachistoscopically for 200 ms (half with, half without blur), to determine whether gaze-contingent blur presentation in Experiment 1 had produced attentional capture by blur onset during a fixation, thus eliminating any effect of cognitive load on blur detection. The results with three new participants replicated those of Experiment 1, indicating that the use of gaze-contingent blur presentation could not explain the lack of effect of cognitive load on blur detection. Thus, apparently blur detection in real-world scene images is unaffected by attentional resources, as manipulated by the

  19. Gender-Specific Effects of Cognitive Load on Social Discounting.

    PubMed

    Strombach, Tina; Margittai, Zsofia; Gorczyca, Barbara; Kalenscher, Tobias

    2016-01-01

    We live busy, social lives, and meeting the challenges of our complex environments puts strain on our cognitive systems. However, cognitive resources are limited. It is unclear how cognitive load affects social decision making. Previous findings on the effects of cognitive load on other-regarding preferences have been ambiguous, allowing no coherent opinion whether cognitive load increases, decreases or does not affect prosocial considerations. Here, we suggest that social distance between individuals modulates whether generosity towards a recipient increases or decreases under cognitive load conditions. Participants played a financial social discounting task with several recipients at variable social distance levels. In this task, they could choose between generous alternatives, yielding medium financial rewards for the participant and recipient at variable social distances, or between a selfish alternative, yielding larger rewards for the participant alone. We show that the social discount function of male participants was significantly flattened under high cognitive load conditions, suggesting they distinguished less between socially close and socially distant recipients. Unexpectedly, the cognitive-load effect on social discounting was gender-specific: while social discounting was strongly dependent on cognitive load in men, women were nearly unaffected by cognitive load manipulations. We suggest that cognitive load leads men, but not women to simplify the decision problem by neglecting the social distance information. We consider our study a good starting point for further experiments exploring the role of gender in prosocial choice.

  20. Gender-Specific Effects of Cognitive Load on Social Discounting

    PubMed Central

    Strombach, Tina; Margittai, Zsofia; Gorczyca, Barbara; Kalenscher, Tobias

    2016-01-01

    We live busy, social lives, and meeting the challenges of our complex environments puts strain on our cognitive systems. However, cognitive resources are limited. It is unclear how cognitive load affects social decision making. Previous findings on the effects of cognitive load on other-regarding preferences have been ambiguous, allowing no coherent opinion whether cognitive load increases, decreases or does not affect prosocial considerations. Here, we suggest that social distance between individuals modulates whether generosity towards a recipient increases or decreases under cognitive load conditions. Participants played a financial social discounting task with several recipients at variable social distance levels. In this task, they could choose between generous alternatives, yielding medium financial rewards for the participant and recipient at variable social distances, or between a selfish alternative, yielding larger rewards for the participant alone. We show that the social discount function of male participants was significantly flattened under high cognitive load conditions, suggesting they distinguished less between socially close and socially distant recipients. Unexpectedly, the cognitive-load effect on social discounting was gender-specific: while social discounting was strongly dependent on cognitive load in men, women were nearly unaffected by cognitive load manipulations. We suggest that cognitive load leads men, but not women to simplify the decision problem by neglecting the social distance information. We consider our study a good starting point for further experiments exploring the role of gender in prosocial choice. PMID:27788192

  1. Selective Impairment of Auditory Selective Attention under Concurrent Cognitive Load

    ERIC Educational Resources Information Center

    Dittrich, Kerstin; Stahl, Christoph

    2012-01-01

    Load theory predicts that concurrent cognitive load impairs selective attention. For visual stimuli, it has been shown that this impairment can be selective: Distraction was specifically increased when the stimulus material used in the cognitive load task matches that of the selective attention task. Here, we report four experiments that…

  2. Pupillary transient responses to within-task cognitive load variation.

    PubMed

    Wong, Hoe Kin; Epps, Julien

    2016-12-01

    Changes in physiological signals due to task evoked cognitive load have been reported extensively. However, pupil size based approaches for estimating cognitive load on a moment-to-moment basis are not as well understood as estimating cognitive load on a task-to-task basis, despite the appeal these approaches have for continuous load estimation. In particular, the pupillary transient response to instantaneous changes in induced load has not been experimentally quantified, and the within-task changes in pupil dilation have not been investigated in a manner that allows their consistency to be quantified with a view to biomedical system design. In this paper, a variation of the digit span task is developed which reliably induces rapid changes of cognitive load to generate task-evoked pupillary responses (TEPRs) associated with large, within-task load changes. Linear modelling and one-way ANOVA reveals that increasing the rate of cognitive loading, while keeping task demands constant, results in a steeper pupillary response. Instantaneous drops in cognitive load are shown to produce statistically significantly different transient pupillary responses relative to sustained load, and when characterised using an exponential decay response, the task-evoked pupillary response time constant is in the order of 1-5 s. Within-task test-retest analysis confirms the reliability of the moment-to-moment measurements. Based on these results, estimates of pupil diameter can be employed with considerably more confidence in moment-to-moment cognitive load estimation systems.

  3. Load theory of selective attention and cognitive control.

    PubMed

    Lavie, Nilli; Hirst, Aleksandra; de Fockert, Jan W; Viding, Essi

    2004-09-01

    A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings suggest 2 selective attention mechanisms: a perceptual selection mechanism serving to reduce distractor perception in situations of high perceptual load that exhaust perceptual capacity in processing relevant stimuli and a cognitive control mechanism that reduces interference from perceived distractors as long as cognitive control functions are available to maintain current priorities (low cognitive load). This theory resolves the long-standing early versus late selection debate and clarifies the role of cognitive control in selective attention.

  4. Raising Cognitive Load with Linear Multimedia to Promote Conceptual Change

    ERIC Educational Resources Information Center

    Muller, Derek A.; Sharma, Manjula D.; Reimann, Peter

    2008-01-01

    Two disparate research programs have addressed the challenge of instructional multimedia design. One, based on cognitive load theory, has focused on ways of reducing unnecessary cognitive load during instruction to free up resources for learning. The other, based on constructivism, has centered on interactive multimedia, allowing students to build…

  5. Solving Complex Problems: A Convergent Approach to Cognitive Load Measurement

    ERIC Educational Resources Information Center

    Zheng, Robert; Cook, Anne

    2012-01-01

    The study challenged the current practices in cognitive load measurement involving complex problem solving by manipulating the presence of pictures in multiple rule-based problem-solving situations and examining the cognitive load resulting from both off-line and online measures associated with complex problem solving. Forty-eight participants…

  6. Complex Mobile Learning That Adapts to Learners' Cognitive Load

    ERIC Educational Resources Information Center

    Deegan, Robin

    2015-01-01

    Mobile learning is cognitively demanding and frequently the ubiquitous nature of mobile computing means that mobile devices are used in cognitively demanding environments. This paper examines the use of mobile devices from a Learning, Usability and Cognitive Load Theory perspective. It suggests scenarios where these fields interact and presents an…

  7. Cognitive Load Theory and the Use of Educational Technology

    ERIC Educational Resources Information Center

    Sweller, John

    2008-01-01

    Human cognitive architecture is a constant in a continually advancing educational technology environment. That architecture should be central in determining which technologies should be adopted and how they should be used. In this article, cognitive load theory is used to indicate aspects of human cognition relevant to instructional design, with…

  8. Effects of the Physical Environment on Cognitive Load and Learning: Towards a New Model of Cognitive Load

    ERIC Educational Resources Information Center

    Choi, Hwan-Hee; van Merriënboer, Jeroen J. G.; Paas, Fred

    2014-01-01

    Although the theoretical framework of cognitive load theory has acknowledged a role for the learning environment, the specific characteristics of the physical learning environment that could affect cognitive load have never been considered, neither theoretically nor empirically. In this article, we argue that the physical learning environment, and…

  9. Cue Utilization and Cognitive Load in Novel Task Performance

    PubMed Central

    Brouwers, Sue; Wiggins, Mark W.; Helton, William; O’Hare, David; Griffin, Barbara

    2016-01-01

    This study was designed to examine whether differences in cue utilization were associated with differences in performance during a novel, simulated rail control task, and whether these differences reflected a reduction in cognitive load. Two experiments were conducted, the first of which involved the completion of a 20-min rail control simulation that required participants to re-route trains that periodically required a diversion. Participants with a greater level of cue utilization recorded a consistently greater response latency, consistent with a strategy that maintained accuracy, but reduced the demands on cognitive resources. In the second experiment, participants completed the rail task, during which a concurrent, secondary task was introduced. The results revealed an interaction, whereby participants with lesser levels of cue utilization recorded an increase in response latency that exceeded the response latency recorded for participants with greater levels of cue utilization. The relative consistency of response latencies for participants with greater levels of cue utilization, across all blocks, despite the imposition of a secondary task, suggested that those participants with greater levels of cue utilization had adopted a strategy that was effectively minimizing the impact of additional sources of cognitive load on their performance. PMID:27064669

  10. Motor imagery of locomotion with an additional load: actual load experience does not affect differences between physical and mental durations.

    PubMed

    Munzert, Jörn; Blischke, Klaus; Krüger, Britta

    2015-03-01

    Motor imagery relies strongly on motor representations. Currently, it is widely accepted that both the imagery and execution of actions share the same neural representations (Jeannerod, Neuroimage 14:S103-S109, 2001). Comparing mental with actual movement durations opens a window through which to examine motor representations and how they relate to cognitive motor processes. The present experiment examined mental durations reported by participants standing upright who imagined walking either with or without an additional load while actually carrying or not carrying that same load. Results showed a robust effect of longer durations when imagining the additional load during mental walking, whereas physical walking with an additional load did not extend movement durations accordingly. However, experiencing an actual load during imagery did not influence mental durations substantially. This dissociation of load-related effects can be interpreted as being due to an interaction of motor processes and their cognitive representation along with a reduction in neural activity in vestibular and somatosensory areas during imagery of locomotion. It is argued that this effect might be specific to locomotion and not generalize to a broader range of movements.

  11. The Role of Cognitive and Perceptual Loads in Inattentional Deafness

    PubMed Central

    Causse, Mickaël; Imbert, Jean-Paul; Giraudet, Louise; Jouffrais, Christophe; Tremblay, Sébastien

    2016-01-01

    The current study examines the role of cognitive and perceptual loads in inattentional deafness (the failure to perceive an auditory stimulus) and the possibility to predict this phenomenon with ocular measurements. Twenty participants performed Air Traffic Control (ATC) scenarios—in the Laby ATC-like microworld—guiding one (low cognitive load) or two (high cognitive load) aircraft while responding to visual notifications related to 7 (low perceptual load) or 21 (high perceptual load) peripheral aircraft. At the same time, participants were played standard tones which they had to ignore (probability = 0.80), or deviant tones (probability = 0.20) which they had to report. Behavioral results showed that 28.76% of alarms were not reported in the low cognitive load condition and up to 46.21% in the high cognitive load condition. On the contrary, perceptual load had no impact on the inattentional deafness rate. Finally, the mean pupil diameter of the fixations that preceded the target tones was significantly lower in the trials in which the participants did not report the tones, likely showing a momentary lapse of sustained attention, which in turn was associated to the occurrence of inattentional deafness. PMID:27458362

  12. The impact of cognitive load on operatic singers' timing performance

    PubMed Central

    Çorlu, Muzaffer; Maes, Pieter-Jan; Muller, Chris; Kochman, Katty; Leman, Marc

    2015-01-01

    In the present paper, we report the results of an empirical study on the effects of cognitive load on operatic singing. The main aim of the study was to investigate to what extent a working memory task affected the timing of operatic singers' performance. Thereby, we focused on singers' tendency to speed up, or slow down their performance of musical phrases and pauses. Twelve professional operatic singers were asked to perform an operatic aria three times; once without an additional working memory task, once with a concurrent working memory task (counting shapes on a computer screen), and once with a relatively more difficult working memory task (more shapes to be counted appearing one after another). The results show that, in general, singers speeded up their performance under heightened cognitive load. Interestingly, this effect was more pronounced in pauses—more in particular longer pauses—compared to musical phrases. We discuss the role of sensorimotor control and feedback processes in musical timing to explain these findings. PMID:25954218

  13. Dynamic hub load predicts cognitive decline after resective neurosurgery.

    PubMed

    Carbo, Ellen W S; Hillebrand, Arjan; van Dellen, Edwin; Tewarie, Prejaas; de Witt Hamer, Philip C; Baayen, Johannes C; Klein, Martin; Geurts, Jeroen J G; Reijneveld, Jaap C; Stam, Cornelis J; Douw, Linda

    2017-02-07

    Resective neurosurgery carries the risk of postoperative cognitive deterioration. The concept of 'hub (over)load', caused by (over)use of the most important brain regions, has been theoretically postulated in relation to symptomatology and neurological disease course, but lacks experimental confirmation. We investigated functional hub load and postsurgical cognitive deterioration in patients undergoing lesion resection. Patients (n = 28) underwent resting-state magnetoencephalography and neuropsychological assessments preoperatively and 1-year after lesion resection. We calculated stationary hub load score (SHub) indicating to what extent brain regions linked different subsystems; high SHub indicates larger processing pressure on hub regions. Dynamic hub load score (DHub) assessed its variability over time; low values, particularly in combination with high SHub values, indicate increased load, because of consistently high usage of hub regions. Hypothetically, increased SHub and decreased DHub relate to hub overload and thus poorer/deteriorating cognition. Between time points, deteriorating verbal memory performance correlated with decreasing upper alpha DHub. Moreover, preoperatively low DHub values accurately predicted declining verbal memory performance. In summary, dynamic hub load relates to cognitive functioning in patients undergoing lesion resection: postoperative cognitive decline can be tracked and even predicted using dynamic hub load, suggesting it may be used as a prognostic marker for tailored treatment planning.

  14. Dynamic hub load predicts cognitive decline after resective neurosurgery

    PubMed Central

    Carbo, Ellen W. S.; Hillebrand, Arjan; van Dellen, Edwin; Tewarie, Prejaas; de Witt Hamer, Philip C.; Baayen, Johannes C.; Klein, Martin; Geurts, Jeroen J. G.; Reijneveld, Jaap C.; Stam, Cornelis J.; Douw, Linda

    2017-01-01

    Resective neurosurgery carries the risk of postoperative cognitive deterioration. The concept of ‘hub (over)load’, caused by (over)use of the most important brain regions, has been theoretically postulated in relation to symptomatology and neurological disease course, but lacks experimental confirmation. We investigated functional hub load and postsurgical cognitive deterioration in patients undergoing lesion resection. Patients (n = 28) underwent resting-state magnetoencephalography and neuropsychological assessments preoperatively and 1-year after lesion resection. We calculated stationary hub load score (SHub) indicating to what extent brain regions linked different subsystems; high SHub indicates larger processing pressure on hub regions. Dynamic hub load score (DHub) assessed its variability over time; low values, particularly in combination with high SHub values, indicate increased load, because of consistently high usage of hub regions. Hypothetically, increased SHub and decreased DHub relate to hub overload and thus poorer/deteriorating cognition. Between time points, deteriorating verbal memory performance correlated with decreasing upper alpha DHub. Moreover, preoperatively low DHub values accurately predicted declining verbal memory performance. In summary, dynamic hub load relates to cognitive functioning in patients undergoing lesion resection: postoperative cognitive decline can be tracked and even predicted using dynamic hub load, suggesting it may be used as a prognostic marker for tailored treatment planning. PMID:28169349

  15. Cognitive Load Mediates the Effect of Emotion on Analytical Thinking.

    PubMed

    Trémolière, Bastien; Gagnon, Marie-Ève; Blanchette, Isabelle

    2016-11-01

    Although the detrimental effect of emotion on reasoning has been evidenced many times, the cognitive mechanism underlying this effect remains unclear. In the present paper, we explore the cognitive load hypothesis as a potential explanation. In an experiment, participants solved syllogistic reasoning problems with either neutral or emotional contents. Participants were also presented with a secondary task, for which the difficult version requires the mobilization of cognitive resources to be correctly solved. Participants performed overall worse and took longer on emotional problems than on neutral problems. Performance on the secondary task, in the difficult version, was poorer when participants were reasoning about emotional, compared to neutral contents, consistent with the idea that processing emotion requires more cognitive resources. Taken together, the findings afford evidence that the deleterious effect of emotion on reasoning is mediated by cognitive load.

  16. How does cognitive load influence speech perception? An encoding hypothesis.

    PubMed

    Mitterer, Holger; Mattys, Sven L

    2017-01-01

    Two experiments investigated the conditions under which cognitive load exerts an effect on the acuity of speech perception. These experiments extend earlier research by using a different speech perception task (four-interval oddity task) and by implementing cognitive load through a task often thought to be modular, namely, face processing. In the cognitive-load conditions, participants were required to remember two faces presented before the speech stimuli. In Experiment 1, performance in the speech-perception task under cognitive load was not impaired in comparison to a no-load baseline condition. In Experiment 2, we modified the load condition minimally such that it required encoding of the two faces simultaneously with the speech stimuli. As a reference condition, we also used a visual search task that in earlier experiments had led to poorer speech perception. Both concurrent tasks led to decrements in the speech task. The results suggest that speech perception is affected even by loads thought to be processed modularly, and that, critically, encoding in working memory might be the locus of interference.

  17. What does germane load mean? An empirical contribution to the cognitive load theory

    PubMed Central

    Debue, Nicolas; van de Leemput, Cécile

    2014-01-01

    While over the last decades, much attention has been paid to the mental workload in the field of human computer interactions, there is still a lack of consensus concerning the factors that generate it as well as the measurement methods that could reflect workload variations. Based on the multifactorial Cognitive Load Theory (CLT), our study aims to provide some food for thought about the subjective and objective measurement that can be used to disentangle the intrinsic, extraneous, and germane load. The purpose is to provide insight into the way cognitive load can explain how users' cognitive resources are allocated in the use of hypermedia, such as an online newspaper. A two-phase experiment has been conducted on the information retention from online news stories. Phase 1 (92 participants) examined the influence of multimedia content on performance as well as the relationships between cognitive loads and cognitive absorption. In Phase 2 (36 participants), eye-tracking data were collected in order to provide reliable and objective measures. Results confirmed that performance in information retention was impacted by the presence of multimedia content such as animations and pictures. The higher number of fixations on these animations suggests that users' attention could have been attracted by them. Results showed the expected opposite relationships between germane and extraneous load, a positive association between germane load and cognitive absorption and a non-linear association between intrinsic and germane load. The trends based on eye-tracking data analysis provide some interesting findings about the relationship between longer fixations, shorter saccades and cognitive load. Some issues are raised about the respective contribution of mean pupil diameter and Index of Cognitive Activity. PMID:25324806

  18. A Comparison of Three Measures of Cognitive Load: Evidence for Separable Measures of Intrinsic, Extraneous, and Germane Load

    ERIC Educational Resources Information Center

    DeLeeuw, Krista E.; Mayer, Richard E.

    2008-01-01

    Understanding how to measure cognitive load is a fundamental challenge for cognitive load theory. In 2 experiments, 155 college students (ages = 17 to 22; 49 men and 106 women) with low domain knowledge learned from a multimedia lesson on electric motors. At 8 points during learning, their cognitive load was measured via self-report scales (mental…

  19. The Influence of Cognitive Load on Empathy and Intention in Response to Infant Crying

    PubMed Central

    Hiraoka, Daiki; Nomura, Michio

    2016-01-01

    Many studies have explored risk factors for child maltreatment, but little research has focused on situational risk factors such as cognitive load, which involves within-individual fluctuation. The current study sought to determine whether cognitive load led to within-individual changes in intention in response to infant crying. The study also sought to ascertain whether state empathy, empathic concern (EC), and personal distress mediated or moderated this relationship. Sixty-six participants completed a memory task (remembering meaningless, two- or eight-letter, English alphabet string), during which they were required to keep these letters in mind while hearing infant crying (or a tone). Subsequently, participants rated questions concerning state empathy and intention in response to the crying (i.e., intentions involving caregiving, neglect, or physical abuse). Results showed that cognitive load reduced caregiving intention and increased intention to perpetrate neglect. In addition, EC mediated the relationship between cognitive load and intention to provide care or perpetrate neglect. Moreover, cognitive load interacted with state empathy to predict intention to provide care or perpetrate neglect. These findings highlighted the importance of focusing on situational cognitive risk factors for child maltreatment and elucidated the role of state empathy as a mediator or moderator in child maltreatment research. PMID:27305959

  20. Processing Capacity under Perceptual and Cognitive Load: A Closer Look at Load Theory

    ERIC Educational Resources Information Center

    Fitousi, Daniel; Wenger, Michael J.

    2011-01-01

    Variations in perceptual and cognitive demands (load) play a major role in determining the efficiency of selective attention. According to load theory (Lavie, Hirst, Fockert, & Viding, 2004) these factors (a) improve or hamper selectivity by altering the way resources (e.g., processing capacity) are allocated, and (b) tap resources rather than…

  1. Cognitive-load approaches to detect deception: searching for cognitive mechanisms

    PubMed Central

    Blandón-Gitlin, Iris; Fenn, Elise; Masip, Jaume; Yoo, Aspen H.

    2015-01-01

    A current focus in deception research is on developing cognitive-load approaches (CLAs) to detect deception. The aim is to improve lie detection with evidence-based and ecologically valid procedures. Although these approaches show great potential, research on cognitive processes or mechanisms explaining how they operate is lacking. Potential mechanisms underlying the most popular techniques advocated for field application are highlighted. Cognitive scientists are encouraged to conduct basic research that qualifies the ‘cognitive’ in these new approaches. PMID:25168448

  2. Decreasing Cognitive Load for Learners: Strategy of Web-Based Foreign Language Learning

    ERIC Educational Resources Information Center

    Zhang, Jianfeng

    2013-01-01

    Cognitive load is one of the important factors that influence the effectiveness and efficiency of web-based foreign language learning. Cognitive load theory assumes that human's cognitive capacity in working memory is limited and if it overloads, learning will be hampered, so that high level of cognitive load can affect the performance of learning…

  3. The Effects of Metaphorical Interface on Germane Cognitive Load in Web-Based Instruction

    ERIC Educational Resources Information Center

    Cheon, Jongpil; Grant, Michael M.

    2012-01-01

    The purpose of this study was to examine the effects of a metaphorical interface on germane cognitive load in Web-based instruction. Based on cognitive load theory, germane cognitive load is a cognitive investment for schema construction and automation. A new instrument developed in a previous study was used to measure students' mental activities…

  4. A Relationship Study of Student Satisfaction with Learning Online and Cognitive Load: Initial Results

    ERIC Educational Resources Information Center

    Bradford, George R.

    2011-01-01

    This study sought to explore if a relationship exists between cognitive load and student satisfaction with learning online. The study separates academic performance (a.k.a., "learning") from cognitive load and satisfaction to better distinguish influences on cognition (from cognitive load) and motivation (from satisfaction). Considerations that…

  5. The Impact of Cognitive Load Theory on Learning Astronomy

    NASA Astrophysics Data System (ADS)

    Foster, Thomas M.

    2010-01-01

    Every student is different, which is the challenge of astronomy education research (AER) and teaching astronomy. This difference also provides the greatest goal for education researchers - our GUT - we need to be able to quantify these differences and provide explanatory and predictive theories to curriculum developers and teachers. One educational theory that holds promise is Cognitive Load Theory. Cognitive Load Theory begins with the well-established fact that everyone's working memory can hold 7 ± 2 unique items. This quirk of the human brain is why phone numbers are 7 digits long. This quirk is also why we forget peoples’ names after just meeting them, leave the iron on when we leave the house, and become overwhelmed as students of new material. Once the intricacies of Cognitive Load are understood, it becomes possible to design learning environments to marshal the resources students have and guide them to success. Lessons learned from Cognitive Load Theory can and should be applied to learning astronomy. Classroom-ready ideas will be presented.

  6. Reducing Transience during Animation: A Cognitive Load Perspective

    ERIC Educational Resources Information Center

    Ng, Hong Kok; Kalyuga, Slava; Sweller, John

    2013-01-01

    Animation has an inherent advantage over static graphics when presenting dynamic content because it provides a more accurate and realistic depiction. Simultaneously, animation has an inherent disadvantage because most animated information is perceptually transient. In this quasi-experimental study, cognitive load theory was used to investigate the…

  7. The impact of cognitive load on reward evaluation.

    PubMed

    Krigolson, Olave E; Hassall, Cameron D; Satel, Jason; Klein, Raymond M

    2015-11-19

    The neural systems that afford our ability to evaluate rewards and punishments are impacted by a variety of external factors. Here, we demonstrate that increased cognitive load reduces the functional efficacy of a reward processing system within the human medial-frontal cortex. In our paradigm, two groups of participants used performance feedback to estimate the exact duration of one second while electroencephalographic (EEG) data was recorded. Prior to performing the time estimation task, both groups were instructed to keep their eyes still and avoid blinking in line with well established EEG protocol. However, during performance of the time-estimation task, one of the two groups was provided with trial-to-trial-feedback about their performance on the time-estimation task and their eye movements to induce a higher level of cognitive load relative to participants in the other group who were solely provided with feedback about the accuracy of their temporal estimates. In line with previous work, we found that the higher level of cognitive load reduced the amplitude of the feedback-related negativity, a component of the human event-related brain potential associated with reward evaluation within the medial-frontal cortex. Importantly, our results provide further support that increased cognitive load reduces the functional efficacy of a neural system associated with reward processing.

  8. The Expertise Reversal Effect: Cognitive Load and Motivational Explanations

    ERIC Educational Resources Information Center

    Rey, Gunter Daniel; Buchwald, Florian

    2011-01-01

    The expertise reversal effect occurs when a learner's expertise moderates design principles such as the redundancy principle (i.e., redundant information should be excluded rather than included) derived from the cognitive load theory. Although this effect is supported by numerous experiments, indicating an overall large effect size, a variety of…

  9. Cognitive Load in Algebra: Element Interactivity in Solving Equations

    ERIC Educational Resources Information Center

    Ngu, Bing Hiong; Chung, Siu Fung; Yeung, Alexander Seeshing

    2015-01-01

    Central to equation solving is the maintenance of equivalence on both sides of the equation. However, when the process involves an interaction of multiple elements, solving an equation can impose a high cognitive load. The balance method requires operations on both sides of the equation, whereas the inverse method involves operations on one side…

  10. Cognitive Load in Voice Therapy Carry-Over Exercises

    ERIC Educational Resources Information Center

    Iwarsson, Jenny; Morris, David Jackson; Balling, Laura Winther

    2017-01-01

    Purpose: The cognitive load generated by online speech production may vary with the nature of the speech task. This article examines 3 speech tasks used in voice therapy carry-over exercises, in which a patient is required to adopt and automatize new voice behaviors, ultimately in daily spontaneous communication. Method: Twelve subjects produced…

  11. Cognitive Load Theory--Sometimes Less Is More

    ERIC Educational Resources Information Center

    Taylor, Cody

    2013-01-01

    The following paper represents review of the literature examining the current research related to cognitive load theory and more specifically the negative aspects of the redundant on-screen text. The authors describe working and long-term memory and how both factor into human learning through the facilitation of knowledge transfer. Limited working…

  12. An Examination of Game-Based Learning from Theories of Flow Experience and Cognitive Load

    ERIC Educational Resources Information Center

    Lai, Chih-Hung; Chu, Chih-Ming; Liu, Hsiang-Hsuan; Yang, Shun-Bo; Chen, Wei-Hsuan

    2013-01-01

    This study aims to discuss whether game-based learning with the integration of games and digital learning could enhance not only the flow experience in learning but achieve the same flow experience in pure games. In addition, the authors discovered that whether the game-based learning could make learners to reveal higher cognitive load. The…

  13. Cognitive correlates of white matter lesion load and brain atrophy

    PubMed Central

    Dong, Chuanhui; Nabizadeh, Nooshin; Caunca, Michelle; Cheung, Ying Kuen; Rundek, Tatjana; Elkind, Mitchell S.V.; DeCarli, Charles; Sacco, Ralph L.; Stern, Yaakov

    2015-01-01

    Objective: We investigated white matter lesion load and global and regional brain volumes in relation to domain-specific cognitive performance in the stroke-free Northern Manhattan Study (NOMAS) population. Methods: We quantified white matter hyperintensity volume (WMHV), total cerebral volume (TCV), and total lateral ventricular (TLV) volume, as well as hippocampal and cortical gray matter (GM) lobar volumes in a subgroup. We used general linear models to examine MRI markers in relation to domain-specific cognitive performance, adjusting for key covariates. Results: MRI and cognitive data were available for 1,163 participants (mean age 70 ± 9 years; 60% women; 66% Hispanic, 17% black, 15% white). Across the entire sample, those with greater WMHV had worse processing speed. Those with larger TLV volume did worse on episodic memory, processing speed, and semantic memory tasks, and TCV did not explain domain-specific variability in cognitive performance independent of other measures. Age was an effect modifier, and stratified analysis showed that TCV and WMHV explained variability in some domains above age 70. Smaller hippocampal volume was associated with worse performance across domains, even after adjusting for APOE ε4 and vascular risk factors, whereas smaller frontal lobe volumes were only associated with worse executive function. Conclusions: In this racially/ethnically diverse, community-based sample, white matter lesion load was inversely associated with cognitive performance, independent of brain atrophy. Lateral ventricular, hippocampal, and lobar GM volumes explained domain-specific variability in cognitive performance. PMID:26156514

  14. Effects of tryptophan loading on human cognition, mood, and sleep.

    PubMed

    Silber, B Y; Schmitt, J A J

    2010-03-01

    Modulating central serotonergic function by acute tryptophan depletion (ATD) has provided the fundamental insights into which cognitive functions are influenced by serotonin. It may be expected that serotonergic stimulation by tryptophan (Trp) loading could evoke beneficial behavioural changes that mirror those of ATD. The current review examines the evidence for such effects, notably those on cognition, mood and sleep. Reports vary considerably across different cognitive domains, study designs, and populations. It is hypothesised that the effects of Trp loading on performance may be dependent on the initial state of the serotonergic system of the subject. Memory improvements following Trp loading have generally been shown in clinical and sub-clinical populations where initial serotonergic disturbances are known. Similarly, Trp loading appears to be most effective for improving mood in vulnerable subjects, and improves sleep in adults with some sleep disturbances. Research has consistently shown Trp loading impairs psychomotor and reaction time performance, however, this is likely to be attributed to its mild sedative effects.

  15. The roles of sensory function and cognitive load in age differences in inhibition: Evidence from the Stroop task.

    PubMed

    Peng, Huamao; Gao, Yue; Mao, Xiaofei

    2017-02-01

    To explore the roles of visual function and cognitive load in aging of inhibition, the present study adopted a 2 (visual perceptual stress: noise, nonnoise) × 2 (cognitive load: low, high) × 2 (age: young, old) mixed design. The Stroop task was adopted to measure inhibition. The task presentation was masked with Gaussian noise according to the visual function of each individual in order to match visual perceptual stress between age groups. The results indicated that age differences in the Stroop effect were influenced by visual function and cognitive load. When the cognitive load was low, older adults exhibited a larger Stroop effect than did younger adults in the nonnoise condition, and this age difference disappeared when the visual noise of the 2 age groups was matched. Conversely, in the high cognitive load condition, we observed significant age differences in the Stroop effect in both the nonnoise and noise conditions. The additional cognitive load made the age differences in the Stroop task reappear even when visual perceptual stress was equivalent. These results demonstrate that visual function plays an important role in the aging of inhibition and its role is moderated by cognitive load. (PsycINFO Database Record

  16. Perceptual and Cognitive Load Interact to Control the Spatial Focus of Attention

    ERIC Educational Resources Information Center

    Linnell, Karina J.; Caparos, Serge

    2011-01-01

    Caparos and Linnell (2009, 2010) used a variable-separation flanker paradigm to show that (a) when cognitive load is low, increasing perceptual load causes spatial attention to focus and (b) when perceptual load is high, decreasing cognitive load causes spatial attention to focus. Here, we tested whether the effects of perceptual and cognitive…

  17. Measuring Cognitive Load and Cognition: Metrics for Technology-Enhanced Learning

    ERIC Educational Resources Information Center

    Martin, Stewart

    2014-01-01

    This critical and reflective literature review examines international research published over the last decade to summarise the different kinds of measures that have been used to explore cognitive load and critiques the strengths and limitations of those focussed on the development of direct empirical approaches. Over the last 40 years, cognitive…

  18. Cognitive Load Does Not Affect the Behavioral and Cognitive Foundations of Social Cooperation.

    PubMed

    Mieth, Laura; Bell, Raoul; Buchner, Axel

    2016-01-01

    The present study serves to test whether the cognitive mechanisms underlying social cooperation are affected by cognitive load. Participants interacted with trustworthy-looking and untrustworthy-looking partners in a sequential Prisoner's Dilemma Game. Facial trustworthiness was manipulated to stimulate expectations about the future behavior of the partners which were either violated or confirmed by the partners' cheating or cooperation during the game. In a source memory test, participants were required to recognize the partners and to classify them as cheaters or cooperators. A multinomial model was used to disentangle item memory, source memory and guessing processes. We found an expectancy-congruent bias toward guessing that trustworthy-looking partners were more likely to be associated with cooperation than untrustworthy-looking partners. Source memory was enhanced for cheating that violated the participants' positive expectations about trustworthy-looking partners. We were interested in whether or not this expectancy-violation effect-that helps to revise unjustified expectations about trustworthy-looking partners-depends on cognitive load induced via a secondary continuous reaction time task. Although this secondary task interfered with working memory processes in a validation study, both the expectancy-congruent guessing bias as well as the expectancy-violation effect were obtained with and without cognitive load. These findings support the hypothesis that the expectancy-violation effect is due to a simple mechanism that does not rely on demanding elaborative processes. We conclude that most cognitive mechanisms underlying social cooperation presumably operate automatically so that they remain unaffected by cognitive load.

  19. Cognitive Load Does Not Affect the Behavioral and Cognitive Foundations of Social Cooperation

    PubMed Central

    Mieth, Laura; Bell, Raoul; Buchner, Axel

    2016-01-01

    The present study serves to test whether the cognitive mechanisms underlying social cooperation are affected by cognitive load. Participants interacted with trustworthy-looking and untrustworthy-looking partners in a sequential Prisoner’s Dilemma Game. Facial trustworthiness was manipulated to stimulate expectations about the future behavior of the partners which were either violated or confirmed by the partners’ cheating or cooperation during the game. In a source memory test, participants were required to recognize the partners and to classify them as cheaters or cooperators. A multinomial model was used to disentangle item memory, source memory and guessing processes. We found an expectancy-congruent bias toward guessing that trustworthy-looking partners were more likely to be associated with cooperation than untrustworthy-looking partners. Source memory was enhanced for cheating that violated the participants’ positive expectations about trustworthy-looking partners. We were interested in whether or not this expectancy-violation effect—that helps to revise unjustified expectations about trustworthy-looking partners—depends on cognitive load induced via a secondary continuous reaction time task. Although this secondary task interfered with working memory processes in a validation study, both the expectancy-congruent guessing bias as well as the expectancy-violation effect were obtained with and without cognitive load. These findings support the hypothesis that the expectancy-violation effect is due to a simple mechanism that does not rely on demanding elaborative processes. We conclude that most cognitive mechanisms underlying social cooperation presumably operate automatically so that they remain unaffected by cognitive load. PMID:27630597

  20. The Role of Cognitive Load in Intentional Forgetting Using the Think/No-Think Task.

    PubMed

    Noreen, Saima; de Fockert, Jan W

    2017-01-01

    We investigated the role of cognitive control in intentional forgetting by manipulating working memory load during the think/no-think task. In two experiments, participants learned a series of cue-target word pairs and were asked to recall the target words associated with some cues or to avoid thinking about the target associated with other cues. In addition to this, participants also performed a modified version of the n-back task which required them to respond to the identity of a single target letter present in the currently presented cue word (n = 0 condition, low working memory load), and in either the previous cue word (n = 1 condition, high working memory load, Experiment 1) or the cue word presented two trials previously (n = 2 condition, high working memory load, Experiment 2). Participants' memory for the target words was subsequently tested using same and novel independent probes. In both experiments it was found that although participants were successful at forgetting on both the same and independent-probe tests in the low working memory load condition, they were only successful at forgetting on the same-probe test in the high working memory load condition. We argue that our findings suggest that the high load working memory task diverted attention from direct suppression and acted as an interference-based strategy. Thus, when cognitive resources are limited participants can switch between the strategies they use to prevent unwanted memories from coming to mind.

  1. Cognitive load and autonomic response patterns under negative priming demand in depersonalization-derealization disorder.

    PubMed

    Lemche, Erwin; Sierra-Siegert, Mauricio; David, Anthony S; Phillips, Mary L; Gasston, David; Williams, Steven C R; Giampietro, Vincent P

    2016-04-01

    Previous studies have yielded evidence for cognitive processing abnormalities and alterations of autonomic functioning in depersonalization-derealization disorder (DPRD). However, multimodal neuroimaging and psychophysiology studies have not yet been conducted to test for functional and effective connectivity under cognitive stress in patients with DPRD. DPRD and non-referred control subjects underwent a combined Stroop/negative priming task, and the neural correlates of Stroop interference effect, negative priming effect, error rates, cognitive load span and average amplitude of skin conductance responses were ascertained for both groups. Evoked haemodynamic responses for basic Stroop/negative priming activations were compared. For basic Stroop to neutral contrast, patients with DPRD differed in the location (inferior vs. superior lobule) of the parietal region involved, but showed similar activations in the left frontal region. In addition, patients with DPRD also co-activated the dorsomedial prefrontal cortex (BA9) and posterior cingulate cortex (BA31), which were also found to be the main between-group difference regions. These regions furthermore showed connectivity with frequency of depersonalization states. Evoked haemodynamic responses drawn from regions of interest indicated significant between-group differences in 30-40% of time points. Brain-behaviour correlations differed mainly in laterality, yet only slightly in regions. A reversal of autonomic patterning became evident in patients with DPRD for cognitive load spans, indicating less effective arousal suppression under cognitive stress - patients with DPRD showed positive associations of cognitive load with autonomic responses, whereas controls exhibit respective inverse association. Overall, the results of the present study show only minor executive cognitive peculiarities, but further support the notion of abnormalities in autonomic functioning in patients with DPRD.

  2. Cognitive Load Theory, Educational Research, and Instructional Design: Some Food for Thought

    ERIC Educational Resources Information Center

    de Jong, Ton

    2010-01-01

    Cognitive load is a theoretical notion with an increasingly central role in the educational research literature. The basic idea of cognitive load theory is that cognitive capacity in working memory is limited, so that if a learning task requires too much capacity, learning will be hampered. The recommended remedy is to design instructional systems…

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

    ERIC Educational Resources Information Center

    Chen, I-Jung; Chang, Chi-Cheng

    2009-01-01

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

  4. Measuring Cognitive Load: A Comparison of Self-Report and Physiological Methods

    ERIC Educational Resources Information Center

    Joseph, Stacey

    2013-01-01

    This study explored three methods to measure cognitive load in a learning environment using four logic puzzles that systematically varied in level of intrinsic cognitive load. Participants' perceived intrinsic load was simultaneously measured with a self-report measure-a traditional subjective measure-and two objective, physiological measures…

  5. Learning anatomy via mobile augmented reality: Effects on achievement and cognitive load.

    PubMed

    Küçük, Sevda; Kapakin, Samet; Göktaş, Yüksel

    2016-10-01

    Augmented reality (AR), a new generation of technology, has attracted the attention of educators in recent years. In this study, a MagicBook was developed for a neuroanatomy topic by using mobile augmented reality (mAR) technology. This technology integrates virtual learning objects into the real world and allow users to interact with the environment using mobile devices. The purpose of this study was to determine the effects of learning anatomy via mAR on medical students' academic achievement and cognitive load. The mixed method was applied in the study. The random sample consisted of 70 second-year undergraduate medical students: 34 in an experimental group and 36 in a control group. Academic achievement test and cognitive load scale were used as data collection tool. A one-way MANOVA test was used for analysis. The experimental group, which used mAR applications, reported higher achievement and lower cognitive load. The use of mAR applications in anatomy education contributed to the formation of an effective and productive learning environment. Student cognitive load decreased as abstract information became concrete in printed books via multimedia materials in mAR applications. Additionally, students were able to access the materials in the MagicBook anytime and anywhere they wanted. The mobile learning approach helped students learn better by exerting less cognitive effort. Moreover, the sensory experience and real time interaction with environment may provide learning satisfaction and enable students to structure their knowledge to complete the learning tasks. Anat Sci Educ 9: 411-421. © 2016 American Association of Anatomists.

  6. Theta oscillations are affected by amnestic mild cognitive impairment and cognitive load.

    PubMed

    Cummins, Tarrant D R; Broughton, Megan; Finnigan, Simon

    2008-10-01

    Amnestic mild cognitive impairment (aMCI) is classified primarily via substantial episodic memory deficits in the absence of a dementia diagnosis. To investigate the potential neurophysiological correlates of such deficits we compared QEEG power between 12 participants with aMCI and 12 healthy matched controls. EEG was acquired during performance of a modified Sternberg word recognition task with low and high memory load conditions. While recognition accuracy of aMCI participants was lower than that of controls, this difference was not significant. Nevertheless the aMCI group demonstrated significantly lower theta power at a number of electrode sites and significant correlations were observed between power at these sites and neuropsychological assessment scores. Furthermore in the aMCI sample only, theta power was significantly lower under high versus low memory load. Given current interpretations of the neural generator(s), as well as the role(s), of theta oscillations in cognitive processes, the present data indicate that aMCI may be associated with disruptions in the operation of neurocognitive networks (e.g., MTL-neocortical), particularly under high cognitive load.

  7. A Mixed Methods Approach to Investigating Cognitive Load and Cognitive Presence in an Online and Face-to-Face College Algebra Course

    ERIC Educational Resources Information Center

    Mills, Jodi Jean

    2016-01-01

    Most research on Cognitive Load Theory (Sweller, 1988) has uncovered many instructional design considerations for learning complex tasks. Additionally, the Community of Inquiry (Garrison, Anderson, & Archer, 2000) framework describes many of the learning experiences in online education. A gap existed in the literature for investigating…

  8. Cognitive load and modelling of an algebra problem

    NASA Astrophysics Data System (ADS)

    Chinnappan, Mohan

    2010-09-01

    In the present study, I examine a modelling strategy as employed by a teacher in the context of an algebra lesson. The actions of this teacher suggest that a modelling approach will have a greater impact on enriching student learning if we do not lose sight of the need to manage associated cognitive loads that could either aid or hinder the integration of core concepts with processes that are at play. Results here also show that modelling a problem that is set within an authentic context helps learners develop a better appreciation of variables and relations that constitute the model. The teacher's scaffolding actions revealed the use of strategies that foster the development of connected, meaningful and more useable algebraic knowledge.

  9. Relationships of cognitive load on eating and weight-related behaviors of young adults.

    PubMed

    Byrd-Bredbenner, Carol; Quick, Virginia; Koenings, Mallory; Martin-Biggers, Jennifer; Kattelmann, Kendra K

    2016-04-01

    Little is known about the relationship between weight-related behaviors and cognitive load (working memory available to complete mental activities like those required for planning meals, selecting foods, and other health-related decisions). Thus, the purpose of this study was to explore associations between cognitive load and eating behaviors, physical activity, body mass index (BMI), and waist circumference of college students. College students (n=1018) from 13 institutions completed an online survey assessing eating behaviors (e.g., routine and compensatory restraint, emotional eating, and fruit/vegetable intake), stress level, and physical activity level. BMI and waist circumference were measured by trained researchers. A cognitive load score was derived from stress level, time pressure/income needs, race and nationality. High cognitive load participants (n=425) were significantly (P<0.05) more likely to be female, older, and further along in school than those with low cognitive loads (n=593). Compared to low cognitive load participants, high cognitive load participants were significantly more likely to eat <5 cups of fruits/vegetables/day, have greater routine and compensatory restraint, and greater susceptibility to eating in response to external cues and emotional eating. Both males and females with high cognitive load scores had a non-significant trend toward higher BMIs, waist circumferences, and drinking more alcohol than low cognitive load counterparts. In conclusion, cognitive load may be an important contributor to health behaviors. Understanding how cognitive load may affect eating and other weight-related behaviors could potentially lead to improvements in the effectiveness of obesity prevention and intervention programs.

  10. Processing capacity under perceptual and cognitive load: a closer look at load theory.

    PubMed

    Fitousi, Daniel; Wenger, Michael J

    2011-06-01

    Variations in perceptual and cognitive demands (load) play a major role in determining the efficiency of selective attention. According to load theory (Lavie, Hirst, Fockert, & Viding, 2004) these factors (a) improve or hamper selectivity by altering the way resources (e.g., processing capacity) are allocated, and (b) tap resources rather than data limitations (Norman & Bobrow, 1975). Here we provide an extensive and rigorous set of tests of these assumptions. Predictions regarding changes in processing capacity are tested using the hazard function of the response time (RT) distribution (Townsend & Ashby, 1978; Wenger & Gibson, 2004). The assumption that load taps resource rather than data limitations is examined using measures of sensitivity and bias drawn from signal detection theory (Swets, 1964). All analyses were performed at two levels: the individual and the aggregate. Hypotheses regarding changes in processing capacity were confirmed at the level of the aggregate. Hypotheses regarding resource and data limitations were not completely supported at either level of analysis. And in all of the analyses, we observed substantial individual differences. In sum, the results suggest a need to expand the theoretical vocabulary of load theory, rather than a need to discard it.

  11. Observing prioritization effects on cognition and gait: The effect of increased cognitive load on cognitively healthy older adults' dual-task performance.

    PubMed

    Maclean, Linda M; Brown, Laura J E; Khadra, H; Astell, Arlene J

    2017-03-01

    Previous studies exploring the effects of attention-prioritization on cognitively healthy older adults' gait and cognitive dual task (DT) performance have shown DT cost in gait outcomes but inconsistent effects on cognitive performance, which may reflect task difficulty (the cognitive load). This study aimed to identify whether changing the cognitive load during a walking and counting DT improved the challenge/sensitivity of the cognitive task to observe prioritization effects on concurrent gait and cognitive performance outcomes. Seventy-two cognitively healthy older adults (Mean=73years) walked 15m, counted backwards in 3s and 7s as single tasks (ST), and concurrently walked and counted backwards as DTs. Attention-prioritization was examined in Prioritizing Walking (PW) and Prioritizing Counting (PC) DT conditions. Dual-task performance costs (DTC) were calculated for number of correct cognitive responses (CCR) in the counting tasks, and step-time variability and velocity in the gait task. All DT conditions showed a benefit (DTB) for cognitive outcomes with trade-off cost to gait. In the Serial 3s task, the cognitive DTBs increased in PC over the PW condition (p<0.05), with a greater cost to walking velocity (p<0.05). DT effects were more pronounced in the Serial 7s with a lower cognitive DTB when PC than when PW, (p<0.05) with no trade-off increase in cost to gait outcomes (p<0.05). The findings suggest that increased cognitive load during a gait and cognitive DT produces more pronounced gait measures of attention-prioritization in cognitively healthy older adults. A cognitive load effect was also observed in the cognitive outcomes, with unexpected results.

  12. Cognitive Load for Configuration Comprehension in Computer-Supported Geometry Problem Solving: An Eye Movement Perspective

    ERIC Educational Resources Information Center

    Lin, John Jr-Hung; Lin, Sunny S. J.

    2014-01-01

    The present study investigated (a) whether the perceived cognitive load was different when geometry problems with various levels of configuration comprehension were solved and (b) whether eye movements in comprehending geometry problems showed sources of cognitive loads. In the first investigation, three characteristics of geometry configurations…

  13. Cognitive Load and Alternative Conceptions in Learning Genetics: Effects from Provoking Confusion

    ERIC Educational Resources Information Center

    Poehnl, Sabine; Bogner, Franz X.

    2013-01-01

    Only recently has cognitive load theory been applied in conceptual change approaches. To the authors' knowledge, theirs is the first study to examine the effects on students' cognitive load of an approach contrary to a refutation text design. The authors combined computer and textbook instruction with involving alternative conceptions (ACs) to…

  14. Student Teacher Challenges: Using the Cognitive Load Theory as an Explanatory Lens

    ERIC Educational Resources Information Center

    Moos, Daniel C.; Pitton, Debra

    2014-01-01

    Cognitive load theory (CLT) can explain the challenges faced by student teachers. This study, guided by the CLT, included 26 pre-service teachers. Participants completed a cognitive load self-report questionnaire and were interviewed at two points during their student teaching. Results revealed that student teachers decreased mental effort related…

  15. Differential Effects of Cognitive Load on University Wind Students' Practice

    ERIC Educational Resources Information Center

    Stambaugh, Laura A.

    2013-01-01

    The purpose of this study was to investigate the effects of cognitive load during practice on university wind students' learning. Cognitive load was manipulated through instrument family (woodwind or brass) and the amount of repetition used in practice (highly repetitive or random). University woodwind and valved-brass students (N = 46)…

  16. Selection of Learning Tasks Based on Performance and Cognitive Load Scores as a Way To Optimize the Learning Process.

    ERIC Educational Resources Information Center

    Salden, Ron J. C. M.; Paas, Fred; van Merrienboer, Jeroen J. G.

    To attain highly efficient instructional conditions, it is important to adapt instruction to the individual trainee. This so-called personalization of training by dynamic/automatic task selection is the focus of this paper. Recently, cognitive load measures have been proposed as a useful addition to conventional performance measures like speed and…

  17. Physical Activity Is Associated With Greater Visuospatial Cognitive Functioning Regardless of the Level of Cognitive Load in Elderly Adults.

    PubMed

    Wang, Chun Hao; Tsai, Chia Liang

    2016-02-01

    The study aimed to investigate the effects of regular physical activity on visuospatial cognition in elderly adults, and to further understand the potential neural mechanisms underpinning such effects. We assessed 24 physically active elderly adults and 24 sedentary counterparts using behavioral and neuroelectric measures during a visuospatial cognitive task with different levels of cognitive load. The results showed that the active group had higher behavioral accuracy along with greater P3 amplitudes, regardless of the level of cognitive load. Moreover, the correlation results revealed that physical activity levels were positively associated with accuracy performance in both conditions, while being correlated with frontal P3 amplitudes in the high cognitively demanding condition. However, no significant effects were observed in terms of P3 latency and contingent negative variation. These findings suggest that regular physical activity might be part of an effective lifestyle to attenuate the trajectory of age-related cognitive declines, thus increasing the likelihood of individuals becoming high-functioning older adults.

  18. Mobile Learning Application Interfaces: First Steps to a Cognitive Load Aware System

    ERIC Educational Resources Information Center

    Deegan, Robin

    2013-01-01

    Mobile learning is a cognitively demanding application and more frequently the ubiquitous nature of mobile computing means that mobile devices are used in cognitively demanding environments. This paper examines the nature of this use of mobile devices from a Learning, Usability and Cognitive Load Theory perspective. It suggests scenarios where…

  19. Ambient Persuasive Technology Needs Little Cognitive Effort: The Differential Effects of Cognitive Load on Lighting Feedback versus Factual Feedback

    NASA Astrophysics Data System (ADS)

    Ham, Jaap; Midden, Cees

    Persuasive technology can influence behavior or attitudes by for example providing interactive factual feedback about energy conservation. However, people often lack motivation or cognitive capacity to consciously process such relative complex information (e.g., numerical consumption feedback). Extending recent research that indicates that ambient persuasive technology can persuade the user without receiving the user's conscious attention, we argue here that Ambient Persuasive Technology can be effective while needing only little cognitive resources, and in general can be more influential than more focal forms of persuasive technology. In an experimental study, some participants received energy consumption feedback by means of a light changing color (more green=lower energy consumption, vs. more red=higher energy consumption) and others by means of numbers indicating kWh consumption. Results indicated that ambient feedback led to more conservation than factual feedback. Also, as expected, only for participants processing factual feedback, additional cognitive load lead to slower processing of that feedback. This research sheds light on fundamental characteristics of Ambient Persuasive Technology and Persuasive Lighting, and suggests that it can have important advantages over more focal persuasive technologies without losing its persuasive potential.

  20. Cognitive skills and bacterial load: comparative evidence of costs of cognitive proficiency in birds

    NASA Astrophysics Data System (ADS)

    Soler, Juan José; Peralta-Sánchez, Juan Manuel; Martín-Vivaldi, Manuel; Martín-Platero, Antonio Manuel; Flensted-Jensen, Einar; Møller, Anders Pape

    2012-02-01

    Parasite-mediated selection may affect the evolution of cognitive abilities because parasites may influence development of the brain, but also learning capacity. Here, we tested some predictions of this hypothesis by analyzing the relationship between complex behaviours (feeding innovations (as a measure of behavioural flexibility) and ability to detect foreign eggs in their nests (i.e. a measure of discriminatory ability)) and abundance of microorganisms in different species of birds. A positive relationship would be predicted if these cognitive abilities implied a larger number of visited environments, while if these skills favoured detection and avoidance of risky environments, a negative relationship would be the prediction. Bacterial loads of eggshells, estimated for mesophilic and potentially pathogenic bacteria (i.e. Enterococcus, Staphylococcus and Enterobacteriaceae), were used as a surrogate of probability of contact with pathogenic bacteria. We found that bird species with higher feeding innovation rates and rejection rates of experimental brood parasitic eggs had higher density of bacteria on their eggshells than the average species. Since the analysed groups of microorganisms include pathogenic bacteria, these results suggest that both feeding innovation and ability to recognize foreign eggs are costly and highlight the importance of parasite-mediated selection in explaining the evolution of cognitive abilities in animals.

  1. EFFECT OF NEGATIVE ION ATMOSPHERIC LOADING ON COGNITIVE PERFORMANCE IN HUMAN VOLUNTEERS

    PubMed Central

    Andrade, A. Chitra; Fernandes, Charlotte; Verghese, Leila; Andrade, Chittaranjan

    1992-01-01

    Negative ion atmospheric loading has been reported to affect a range of psychological functions, from alertness to circadian rhythms, and has been suggested to benefit a variety of medical conditions, from allergies to migraine. In a double-blind study planned to assess the effect of negative ions on cognitive performance in human volunteers, 65 female graduate course students were randomized into ionized atmosphere (n = 34) and control (n = 31) groups. The following cognitive tasks were administered: Digit Symbol Substitution Test, Addition Test, Visual Memory (Complex Figure) Test, Verbal Memeory (Complex Passage) Test, Ideational Fluency Test and Clerical Speed and Accuracy test. On all but the last two tests, the negative ion groupperfonned significantly better (to a 15-40% extent) than controls. It is concluded that negative ionization of the atmosphere by artificial means may be of benefit in certain common, practical situation in which depletion of these ions occurs. PMID:21776128

  2. Load Theory of Selective Attention and Cognitive Control

    ERIC Educational Resources Information Center

    Lavie, Nilli; Hirst, Aleksandra; de Fockert, Jan W.; Viding, Essi

    2004-01-01

    A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings…

  3. Failure to loose fear: The impact of cognitive load and trait anxiety on extinction.

    PubMed

    Raes, An K; De Raedt, Rudi; Verschuere, Bruno; De Houwer, Jan

    2009-12-01

    Exposure therapy is an effective technique for fear reduction. However, whether effective exposure requires attentional allocation to the feared situation remains a debated clinical issue. In the present study, the impact of attention allocation in extinction was investigated in an experimental conditioning study. Through a between-subjects manipulation of cognitive load, we created a condition in which participants could allocate their attention to the feared stimulus during extinction (low load condition), and a condition in which attentional allocation was impaired (high load condition). The influence of cognitive load on extinction was examined by comparing electrodermal responses and verbal ratings for the conditioned stimuli in the two extinction load conditions. The results show less successful extinction in the high load condition than in the low load condition. However, this effect was found only in low anxious participants, and it was prominent only on the skin conductance responses. The present results suggest that extinction is not automatic but requires cognitive resources.

  4. Concentration: The Neural Underpinnings of How Cognitive Load Shields Against Distraction.

    PubMed

    Sörqvist, Patrik; Dahlström, Örjan; Karlsson, Thomas; Rönnberg, Jerker

    2016-01-01

    Whether cognitive load-and other aspects of task difficulty-increases or decreases distractibility is subject of much debate in contemporary psychology. One camp argues that cognitive load usurps executive resources, which otherwise could be used for attentional control, and therefore cognitive load increases distraction. The other camp argues that cognitive load demands high levels of concentration (focal-task engagement), which suppresses peripheral processing and therefore decreases distraction. In this article, we employed an functional magnetic resonance imaging (fMRI) protocol to explore whether higher cognitive load in a visually-presented task suppresses task-irrelevant auditory processing in cortical and subcortical areas. The results show that selectively attending to an auditory stimulus facilitates its neural processing in the auditory cortex, and switching the locus-of-attention to the visual modality decreases the neural response in the auditory cortex. When the cognitive load of the task presented in the visual modality increases, the neural response to the auditory stimulus is further suppressed, along with increased activity in networks related to effortful attention. Taken together, the results suggest that higher cognitive load decreases peripheral processing of task-irrelevant information-which decreases distractibility-as a side effect of the increased activity in a focused-attention network.

  5. Too (mentally) busy to chill: Cognitive load and inhibitory cues interact to moderate triggered displaced aggression.

    PubMed

    Vasquez, Eduardo A; Howard-Field, Joanna

    2016-11-01

    Inhibitory information can be expected to reduce triggered displaced aggression by signaling the potential for negative consequences as a result of acting aggressively. We examined how cognitive load might interfere with these aggression-reducing effects of inhibitory cues. Participants (N = 80) were randomly assigned to a condition in a 2 (cognitive load: high/low) × 2 (inhibiting cues: yes/no) between-subjects design. Following procedures in the TDA paradigm, participants received an initial provocation from the experimenter and a subsequent triggering annoyance from another individual. In the inhibitory cue condition, participants were told, before they had the opportunity to aggress, that others would learn of their aggressive responses. In the high cognitive load condition, participants rehearsed a 10-digit number while aggressing. Those in the low cognitive load condition rehearsed a three digit number. We found significant main effects of cognitive load and inhibitory cue, which were qualified by the expected load × inhibitory cue interaction. Thus, inhibitory cues reduced displaced aggression under low-cognitive load. However, when participants in the inhibitory cue condition were under cognitive load, aggression increased, suggesting that mental busyness interfered with the full use of inhibitory information. Aggr. Behav. 42:598-604, 2016. © 2016 Wiley Periodicals, Inc.

  6. Examining the Relationships of Different Cognitive Load Types Related to User Interface in Web-Based Instruction

    ERIC Educational Resources Information Center

    Cheon, Jongpil; Grant, Michael

    2012-01-01

    This study proposes a new instrument to measure cognitive load types related to user interface and demonstrates theoretical assumptions about different load types. In reconsidering established cognitive load theory, the inadequacies of the theory are criticized in terms of the adaption of learning efficiency score and distinction of cognitive load…

  7. Taming a Beast of Burden--On Some Issues with the Conceptualisation and Operationalisation of Cognitive Load

    ERIC Educational Resources Information Center

    Beckmann, Jens F.

    2010-01-01

    Research on cognitive load theory (CLT) has not yet provided facet-specific measures of cognitive load. The lack of valid methods to measure intrinsic, extraneous and germane cognitive load makes it difficult to empirically test theoretical explanations of effects caused by manipulations of instructional designs. This situation also imposes…

  8. Improving the Quality of Online Discussion: The Effects of Strategies Designed Based on Cognitive Load Theory Principles

    ERIC Educational Resources Information Center

    Darabi, Aubteen; Jin, Li

    2013-01-01

    This article focuses on heavy cognitive load as the reason for the lack of quality associated with conventional online discussion. Using the principles of cognitive load theory, four online discussion strategies were designed specifically aiming at reducing the discussants' cognitive load and thus enhancing the quality of their online discussion.…

  9. A Neurocomputational Model of the Effect of Cognitive Load on Freezing of Gait in Parkinson's Disease

    PubMed Central

    Muralidharan, Vignesh; Balasubramani, Pragathi P.; Chakravarthy, V. Srinivasa; Gilat, Moran; Lewis, Simon J. G.; Moustafa, Ahmed A.

    2017-01-01

    Experimental data show that perceptual cues can either exacerbate or ameliorate freezing of gait (FOG) in Parkinson's Disease (PD). For example, simple visual stimuli like stripes on the floor can alleviate freezing whereas complex stimuli like narrow doorways can trigger it. We present a computational model of the cognitive and motor cortico-basal ganglia loops that explains the effects of sensory and cognitive processes on FOG. The model simulates strong causative factors of FOG including decision conflict (a disagreement of various sensory stimuli in their association with a response) and cognitive load (complexity of coupling a stimulus with downstream mechanisms that control gait execution). Specifically, the model simulates gait of PD patients (freezers and non-freezers) as they navigate a series of doorways while simultaneously responding to several Stroop word cues in a virtual reality setup. The model is based on an actor-critic architecture of Reinforcement Learning involving Utility-based decision making, where Utility is a weighted sum of Value and Risk functions. The model accounts for the following experimental data: (a) the increased foot-step latency seen in relation to high conflict cues, (b) the high number of motor arrests seen in PD freezers when faced with a complex cue compared to the simple cue, and (c) the effect of dopamine medication on these motor arrests. The freezing behavior arises as a result of addition of task parameters (doorways and cues) and not due to inherent differences in the subject group. The model predicts a differential role of risk sensitivity in PD freezers and non-freezers in the cognitive and motor loops. Additionally this first-of-its-kind model provides a plausible framework for understanding the influence of cognition on automatic motor actions in controls and Parkinson's Disease. PMID:28119584

  10. Measuring Load on Working Memory: The Use of Heart Rate as a Means of Measuring Chemistry Students' Cognitive Load

    ERIC Educational Resources Information Center

    Cranford, Kristen N.; Tiettmeyer, Jessica M.; Chuprinko, Bryan C.; Jordan, Sophia; Grove, Nathaniel P.

    2014-01-01

    Information processing provides a powerful model for understanding how learning occurs and highlights the important role that cognitive load plays in this process. In instances in which the cognitive load of a problem exceeds the available working memory, learning can be seriously hindered. Previously reported methods for measuring cognitive load…

  11. Concentration: The Neural Underpinnings of How Cognitive Load Shields Against Distraction

    PubMed Central

    Sörqvist, Patrik; Dahlström, Örjan; Karlsson, Thomas; Rönnberg, Jerker

    2016-01-01

    Whether cognitive load—and other aspects of task difficulty—increases or decreases distractibility is subject of much debate in contemporary psychology. One camp argues that cognitive load usurps executive resources, which otherwise could be used for attentional control, and therefore cognitive load increases distraction. The other camp argues that cognitive load demands high levels of concentration (focal-task engagement), which suppresses peripheral processing and therefore decreases distraction. In this article, we employed an functional magnetic resonance imaging (fMRI) protocol to explore whether higher cognitive load in a visually-presented task suppresses task-irrelevant auditory processing in cortical and subcortical areas. The results show that selectively attending to an auditory stimulus facilitates its neural processing in the auditory cortex, and switching the locus-of-attention to the visual modality decreases the neural response in the auditory cortex. When the cognitive load of the task presented in the visual modality increases, the neural response to the auditory stimulus is further suppressed, along with increased activity in networks related to effortful attention. Taken together, the results suggest that higher cognitive load decreases peripheral processing of task-irrelevant information—which decreases distractibility—as a side effect of the increased activity in a focused-attention network. PMID:27242485

  12. Practising what we preach: using cognitive load theory for workshop design and evaluation.

    PubMed

    Naismith, Laura M; Haji, Faizal A; Sibbald, Matthew; Cheung, Jeffrey J H; Tavares, Walter; Cavalcanti, Rodrigo B

    2015-12-01

    Theory-based instructional design is a top priority in medical education. The goal of this Show and Tell article is to present our theory-driven approach to the design of instruction for clinical educators. We adopted cognitive load theory as a framework to design and evaluate a series of professional development workshops that were delivered at local, national and international academic conferences in 2014. We used two rating scales to measure participants' cognitive load. Participants also provided narrative comments as to how the workshops could be improved. Cognitive load ratings from 59 participants suggested that the workshop design optimized learning by managing complexity for different levels of learners (intrinsic load), stimulating cognitive processing for long-term memory storage (germane load), and minimizing irrelevant distracters (extraneous load). Narrative comments could also be classified as representing intrinsic, extraneous, or germane load, which provided specific directions for ongoing quality improvement. These results demonstrate that a cognitive load theory approach to workshop design and evaluation is feasible and useful in the context of medical education.

  13. An Evolutionary Upgrade of Cognitive Load Theory: Using the Human Motor System and Collaboration to Support the Learning of Complex Cognitive Tasks

    ERIC Educational Resources Information Center

    Paas, Fred; Sweller, John

    2012-01-01

    Cognitive load theory is intended to provide instructional strategies derived from experimental, cognitive load effects. Each effect is based on our knowledge of human cognitive architecture, primarily the limited capacity and duration of a human working memory. These limitations are ameliorated by changes in long-term memory associated with…

  14. In Respect to the Cognitive Load Theory: Adjusting Instructional Guidance with Student Expertise.

    PubMed

    Schilling, Jim

    2017-01-01

    The amount of guidance supplied by educators to students in allied health programs is a factor in student learning. According to the cognitive load theory of learning, without adequate instructional support, novice learners will be overwhelmed and unable to store information, while unnecessary guidance supplied to advanced students will cause extraneous cognitive load on the working memory system. Adjusting instructional guidance for students according to their level of expertise to minimize extraneous cognitive load and optimize working memory storage capacity will enhance learning effectiveness. Novice students presented with complex subject matter require significant guidance during the initial stages, using strategies such as worked examples. As students comprehend information, instructional guidance needs to gradually fade to avoid elevated extraneous cognitive load from the expertise reversal effect. An instructional strategy that utilizes a systemic (fixed) or adjustable (adaptive) tapering of guidance to students in allied health programs depending on their expertise will optimize learning capability.

  15. The effects of eye movements on emotional memories: using an objective measure of cognitive load

    PubMed Central

    van Veen, Suzanne C.; Engelhard, Iris M.; van den Hout, Marcel A.

    2016-01-01

    Background Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. The working memory (WM) theory explains its efficacy: recall of an aversive memory and making eye movements (EM) both produce cognitive load, and competition for the limited WM resources reduces the memory's vividness and emotionality. The present study tested several predictions from WM theory. Objective We hypothesized that 1) recall of an aversive autobiographical memory loads WM compared to no recall, and 2) recall with EM reduces the vividness, emotionality, and cognitive load of recalling the memory more than only recall or only cognitive effort (i.e., recall of an irrelevant memory with EM). Method Undergraduates (N=108) were randomly assigned to one of three conditions: 1) recall relevant memory with EM, 2) recall relevant memory without EM, and 3) recall irrelevant memory with EM. We used a random interval repetition task to measure the cognitive load of recalling the memory. Participants responded to randomly administered beeps, with or without recalling the memory. The degree to which participants slow down during recall provides an index of cognitive load. We measured the cognitive load and self-reported vividness and emotionality before, halfway through (8×24 s), and after (16×24 s) the intervention. Results Reaction times slowed down during memory recall compared to no recall. The recall relevant with EM condition showed a larger decrease in self-reported vividness and emotionality than the control conditions. The cognitive load of recalling the memory also decreased in this condition but not consistently more than in the control conditions. Conclusions Recall of an aversive memory loads WM, but drops in vividness and emotionality do not immediately reduce the cognitive load of recalling the memory. More research is needed to find objective measures that could capture changes in the quality of the memory. Highlights of the

  16. Channel selection and feature projection for cognitive load estimation using ambulatory EEG.

    PubMed

    Lan, Tian; Erdogmus, Deniz; Adami, Andre; Mathan, Santosh; Pavel, Misha

    2007-01-01

    We present an ambulatory cognitive state classification system to assess the subject's mental load based on EEG measurements. The ambulatory cognitive state estimator is utilized in the context of a real-time augmented cognition (AugCog) system that aims to enhance the cognitive performance of a human user through computer-mediated assistance based on assessments of cognitive states using physiological signals including, but not limited to, EEG. This paper focuses particularly on the offline channel selection and feature projection phases of the design and aims to present mutual-information-based techniques that use a simple sample estimator for this quantity. Analyses conducted on data collected from 3 subjects performing 2 tasks (n-back/Larson) at 2 difficulty levels (low/high) demonstrate that the proposed mutual-information-based dimensionality reduction scheme can achieve up to 94% cognitive load estimation accuracy.

  17. Total MRI load of cerebral small vessel disease and cognitive ability in older people.

    PubMed

    Staals, Julie; Booth, Tom; Morris, Zoe; Bastin, Mark E; Gow, Alan J; Corley, Janie; Redmond, Paul; Starr, John M; Deary, Ian J; Wardlaw, Joanna M

    2015-10-01

    Cerebral small vessel disease (SVD) may cause cognitive dysfunction. We tested the association between the combined presence of magnetic resonance imaging (MRI) features of SVD and cognitive ability in older age. Cognitive testing and brain MRI were performed in 680 older participants. MRI presence of lacunes, white matter hyperintensities, microbleeds, and perivascular spaces were summed in a score of 0-4 representing all SVD features combined. We also applied latent variable modeling to test whether the 4 MRI features form a unitary SVD construct. The SVD score showed significant associations with general cognitive ability. Latent variable modeling indicated that the 4 MRI markers formed a unitary construct, which showed consistent associations with cognitive ability compared with the SVD score. Total MRI load of SVD is associated with lower general cognitive ability in older age. The total SVD score performed consistently with the more complex latent variable model, suggesting validity and potential utility in future research for determining total SVD load.

  18. Turning a blind eye to temptation: how cognitive load can facilitate self-regulation.

    PubMed

    Van Dillen, Lotte F; Papies, Esther K; Hofmann, Wilhelm

    2013-03-01

    The present research shows in 4 studies that cognitive load can reduce the impact of temptations on cognition and behavior and, thus, challenges the proposition that distraction always hampers self-regulation. Participants performed different speeded categorization tasks with pictures of attractive and neutral food items (Studies 1-3) and attractive and unattractive female faces (Study 4), while we assessed their reaction times as an indicator of selective attention (Studies 1, 3, and 4) or as an indicator of hedonic thoughts about food (Study 2). Cognitive load was manipulated by a concurrent digit span task. Results show that participants displayed greater attention to tempting stimuli (Studies 1, 3, and 4) and activated hedonic thoughts in response to palatable food (Study 2), but high cognitive load completely eliminated these effects. Moreover, cognitive load during the exposure to attractive food reduced food cravings (Study 1) and increased healthy food choices (Study 3). Finally, individual differences in sensitivity to food temptations (Study 3) and interest in alternative relationship partners (Study 4) predicted selective attention to attractive stimuli, but again, only when cognitive load was low. Our findings suggest that recognizing the tempting value of attractive stimuli in our living environment requires cognitive resources. This has the important implication that, contrary to traditional views, performing a concurrent demanding task may actually diminish the captivating power of temptation and thus facilitate self-regulation.

  19. Divergent Effects of Cognitive Load on Quiet Stance and Task-Linked Postural Coordination

    ERIC Educational Resources Information Center

    Mitra, Suvobrata; Knight, Alec; Munn, Alexandra

    2013-01-01

    Performing a cognitive task while maintaining upright stance can lead to increased or reduced body sway depending on tasks and experimental conditions. Because greater sway is commonly taken to indicate loosened postural control, and vice versa, the precise impact of cognitive load on postural stability has remained unclear. In much of the large…

  20. Does Multimedia Support Individual Differences?--EFL Learners' Listening Comprehension and Cognitive Load

    ERIC Educational Resources Information Center

    Yang, Hui-Yu

    2014-01-01

    The present study examines how display model, English proficiency and cognitive preference affect English as a Foreign Language (EFL) learners' listening comprehension of authentic videos and cognitive load degree. EFL learners were randomly assigned to one of two groups. The control group received single coding and the experimental group received…

  1. Example Postings' Effects on Online Discussion and Cognitive Load

    ERIC Educational Resources Information Center

    Jin, Li

    2012-01-01

    This study investigated the effects of example-postings on students' cognitive load and performance in online discussions. Cognitive overload was assumed had caused the problem of the lack of reflective and thoughtful contributions in student discussions. The theoretical foundation supporting the use of example-postings aiming at reduce…

  2. Manipulation of cognitive load variables and impact on auscultation test performance.

    PubMed

    Chen, Ruth; Grierson, Lawrence; Norman, Geoffrey

    2015-10-01

    Health profession educators have identified auscultation skill as a learning need for health professional students. This article explores the application of cognitive load theory (CLT) to designing cardiac and respiratory auscultation skill instruction for senior-level undergraduate nursing students. Three experiments assessed student auscultation performance following instructional manipulations of the three primary components of cognitive load: intrinsic, extraneous, and germane load. Study 1 evaluated the impact of intrinsic cognitive load by varying the number of diagnoses learned in one instruction session; Study 2 evaluated the impact of extraneous cognitive load by providing students with single or multiple examples of diagnoses during instruction; and Study 3 evaluated the impact of germane cognitive load by employing mixed or blocked sequences of diagnostic examples to students. Each of the three studies presents results that support CLT as explaining the influence of different types of cognitive processing on auscultation skill acquisition. We conclude with a discussion regarding CLT's usefulness as a framework for education and education research in the health professions.

  3. Effects of cognitive load on neural and behavioral responses to smoking-cue distractors.

    PubMed

    MacLean, R Ross; Nichols, Travis T; LeBreton, James M; Wilson, Stephen J

    2016-08-01

    Smoking cessation failures are frequently thought to reflect poor top-down regulatory control over behavior. Previous studies have suggested that smoking cues occupy limited working memory resources, an effect that may contribute to difficulty achieving abstinence. Few studies have evaluated the effects of cognitive load on the ability to actively maintain information in the face of distracting smoking cues. For the present study, we adapted an fMRI probed recall task under low and high cognitive load with three distractor conditions: control, neutral images, or smoking-related images. Consistent with a limited-resource model of cue reactivity, we predicted that the performance of daily smokers (n = 17) would be most impaired when high load was paired with smoking distractors. The results demonstrated a main effect of load, with decreased accuracy under high, as compared to low, cognitive load. Surprisingly, an interaction revealed that the effect of load was weakest in the smoking cue distractor condition. Along with this behavioral effect, we observed significantly greater activation of the right inferior frontal gyrus (rIFG) in the low-load condition than in the high-load condition for trials containing smoking cue distractors. Furthermore, load-related changes in rIFG activation partially mediated the effects of load on task accuracy in the smoking-cue distractor condition. These findings are discussed in the context of prevailing cognitive and cue reactivity theories. These results suggest that high cognitive load does not necessarily make smokers more susceptible to interference from smoking-related stimuli, and that elevated load may even have a buffering effect in the presence of smoking cues under certain conditions.

  4. Commentary: Should Gender Differences Be Included in the Evolutionary Upgrade to Cognitive Load Theory?

    ERIC Educational Resources Information Center

    Bevilacqua, Andy

    2017-01-01

    Recent upgrades to cognitive load theory suggest that evolutionary processes have shaped the way that working memory processes cultural and social information. According to evolutionarily educational psychologists, some forms of information are processed with lower working memory loads than other forms. The former are evolutionarily salient and…

  5. Effects of Peer-Tutor Competences on Learner Cognitive Load and Learning Performance during Knowledge Sharing

    ERIC Educational Resources Information Center

    Hsiao, Ya-Ping; Brouns, Francis; van Bruggen, Jan; Sloep, Peter B.

    2012-01-01

    In Learning Networks, learners need to share knowledge with others to build knowledge. In particular, when working on complex tasks, they often need to acquire extra cognitive resources from others to process a high task load. However, without support high task load and organizing knowledge sharing themselves might easily overload learners'…

  6. Working memory load and distraction: dissociable effects of visual maintenance and cognitive control.

    PubMed

    Konstantinou, Nikos; Beal, Eleanor; King, Jean-Remi; Lavie, Nilli

    2014-10-01

    We establish a new dissociation between the roles of working memory (WM) cognitive control and visual maintenance in selective attention as measured by the efficiency of distractor rejection. The extent to which focused selective attention can prevent distraction has been shown to critically depend on the level and type of load involved in the task. High perceptual load that consumes perceptual capacity leads to reduced distractor processing, whereas high WM load that reduces WM ability to exert priority-based executive cognitive control over the task results in increased distractor processing (e.g., Lavie, Trends in Cognitive Sciences, 9(2), 75-82, 2005). WM also serves to maintain task-relevant visual representations, and such visual maintenance is known to recruit the same sensory cortices as those involved in perception (e.g., Pasternak & Greenlee, Nature Reviews Neuroscience, 6(2), 97-107, 2005). These findings led us to hypothesize that loading WM with visual maintenance would reduce visual capacity involved in perception, thus resulting in reduced distractor processing-similar to perceptual load and opposite to WM cognitive control load. Distractor processing was assessed in a response competition task, presented during the memory interval (or during encoding; Experiment 1a) of a WM task. Loading visual maintenance or encoding by increased set size for a memory sample of shapes, colors, and locations led to reduced distractor response competition effects. In contrast, loading WM cognitive control with verbal rehearsal of a random letter set led to increased distractor effects. These findings confirm load theory predictions and provide a novel functional distinction between the roles of WM maintenance and cognitive control in selective attention.

  7. ERPs and the evoked cardiac response to auditory stimuli: Intensity and cognitive load effects.

    PubMed

    Lawrence, Carlie A; Barry, Robert J

    2009-01-01

    The evoked cardiac response (ECR) may be described as the sum of two independent response components: an initial HR deceleration (ECR1) and a slightly later acceleration (ECR2) hypothesized to reflect stimulus registration and cognitive processing load, respectively. This study investigated processing load effects in the ECR and the event-related potential (ERP). Stimulus intensity was varied within subjects, and cognitive load was varied between subjects, in a counting/no counting task with a long interstimulus interval. The ECR showed a significant effect of counting, but not intensity. ERPs showed the expected obligatory processing effects in the N1, and substantial effects of cognitive load in the Late Positive Complex. Both ERP components varied with intensity. These novel data offer support for ANS-CNS similarities in reflecting some aspects of stimulus processing, but further work is needed to understand the possible contribution of ERP subcomponents to these effects.

  8. E-learning, dual-task, and cognitive load: The anatomy of a failed experiment.

    PubMed

    Van Nuland, Sonya E; Rogers, Kem A

    2016-01-01

    The rising popularity of commercial anatomy e-learning tools has been sustained, in part, due to increased annual enrollment and a reduction in laboratory hours across educational institutions. While e-learning tools continue to gain popularity, the research methodologies used to investigate their impact on learning remain imprecise. As new user interfaces are introduced, it is critical to understand how functionality can influence the load placed on a student's memory resources, also known as cognitive load. To study cognitive load, a dual-task paradigm wherein a learner performs two tasks simultaneously is often used, however, its application within educational research remains uncommon. Using previous paradigms as a guide, a dual-task methodology was developed to assess the cognitive load imposed by two commercial anatomical e-learning tools. Results indicate that the standard dual-task paradigm, as described in the literature, is insensitive to the cognitive load disparities across e-learning tool interfaces. Confounding variables included automation of responses, task performance tradeoff, and poor understanding of primary task cognitive load requirements, leading to unreliable quantitative results. By modifying the secondary task from a basic visual response to a more cognitively demanding task, such as a modified Stroop test, the automation of secondary task responses can be reduced. Furthermore, by recording baseline measures for the primary task as well as the secondary task, it is possible for task performance tradeoff to be detected. Lastly, it is imperative that the cognitive load of the primary task be designed such that it does not overwhelm the individual's ability to learn new material.

  9. Measuring physician cognitive load: validity evidence for a physiologic and a psychometric tool.

    PubMed

    Szulewski, Adam; Gegenfurtner, Andreas; Howes, Daniel W; Sivilotti, Marco L A; van Merriënboer, Jeroen J G

    2016-10-27

    In general, researchers attempt to quantify cognitive load using physiologic and psychometric measures. Although the construct measured by both of these metrics is thought to represent overall cognitive load, there is a paucity of studies that compares these techniques to one another. The authors compared data obtained from one physiologic tool (pupillometry) to one psychometric tool (Paas scale) to explore whether they actually measured the construct of cognitive load as purported. Thirty-two participants with a range of resuscitation medicine experience and expertise completed resuscitation-medicine based multiple-choice-questions as well as arithmetic questions. Cognitive load, as measured by both tools, was found to be higher for the more difficult questions as well as for questions that were answered incorrectly (p < 0.001). The group with the least medical experience had higher cognitive load than both the intermediate and experienced groups when answering domain-specific questions (p = 0.023 and p = 0.003 respectively for the physiologic tool; p = 0.006 and p < 0.001 respectively for the psychometric tool). There was a strong positive correlation (Spearman's ρ = 0.827, p < 0.001 for arithmetic questions; Spearman's ρ = 0.606, p < 0.001 for medical questions) between the two cognitive load measurement tools. These findings support the validity argument that both physiologic and psychometric metrics measure the construct of cognitive load.

  10. The impact of luminance on tonic and phasic pupillary responses to sustained cognitive load.

    PubMed

    Peysakhovich, Vsevolod; Vachon, François; Dehais, Frédéric

    2017-02-01

    Pupillary reactions independent of light conditions have been linked to cognition for a long time. However, the light conditions can impact the cognitive pupillary reaction. Previous studies underlined the impact of luminance on pupillary reaction, but it is still unclear how luminance modulates the sustained and transient components of pupillary reaction - tonic pupil diameter and phasic pupil response. In the present study, we investigated the impact of the luminance on these two components under sustained cognitive load. Fourteen participants performed a novel working memory task combining mathematical computations with a classic n-back task. We studied both tonic pupil diameter and phasic pupil response under low (1-back) and high (2-back) working memory load and two luminance levels (gray and white). We found that the impact of working memory load on the tonic pupil diameter was modulated by the level of luminance, the increase in tonic pupil diameter with the load being larger under lower luminance. In contrast, the smaller phasic pupil response found under high load remained unaffected by luminance. These results showed that luminance impacts the cognitive pupillary reaction - tonic pupil diameter (phasic pupil response) being modulated under sustained (respectively, transient) cognitive load. These findings also support the relationship between the locus-coeruleus system, presumably functioning in two firing modes - tonic and phasic - and the pupil diameter. We suggest that the tonic pupil diameter tracks the tonic activity of the locus-coeruleus while phasic pupil response reflects its phasic activity. Besides, the designed novel cognitive paradigm allows the simultaneous manipulation of sustained and transient components of the cognitive load and is useful for dissociating the effects on the tonic pupil diameter and phasic pupil response.

  11. Effect of Cognitive Load on Seating Posture in Children.

    PubMed

    Igarashi, Go; Karashima, Chieko; Hoshiyama, Minoru

    2016-03-01

    Although children are frequently required to sit upright, it is often difficult to maintain this posture when performing cognitive tasks. Information about the relationship between a cognitive tasks and postural seating control is important for children to complete tasks more effectively. To determine the muscle activity and body sway of children in a seated posture while performing a cognitive task, changes in muscle activity and center of pressure (COP) were recorded while 4(th) grade children performed arithmetic tasks. Electromyography was recorded from the internal oblique and lumbar multifidus muscles, and the COP was recorded using a baropodometer placed on the stool. These variables were measured during easy (EA) and difficult (DA) arithmetic tasks. EMG activity decreased during the EA and DA tasks, while the COP was displaced in the DA task. The results of the arithmetic tasks were not related to the EMG or COP changes. Attention to maintain a seated posture may be reduced when children perform cognitive tasks. Therefore, it may be better to allow children to alter their posture especially when they are performing difficult tasks. In this research, we only used arithmetic tasks as the cognitive exercise, and therefore, other types of tasks should be examined.

  12. Modeling cognitive loads for evolving shared mental models in human-agent collaboration.

    PubMed

    Fan, Xiaocong; Yen, John

    2011-04-01

    Recent research on human-centered teamwork highly demands the design of cognitive agents that can model and exploit human partners' cognitive load to enhance team performance. In this paper, we focus on teams composed of human-agent pairs and develop a system called Shared Mental Models for all--SMMall. SMMall implements a hidden Markov model (HMM)-based cognitive load model for an agent to predict its human partner's instantaneous cognitive load status. It also implements a user interface (UI) concept called shared belief map, which offers a synergic representation of team members' information space and allows them to share beliefs. An experiment was conducted to evaluate the HMM-based load models. The results indicate that the HMM-based load models are effective in helping team members develop a shared mental model (SMM), and the benefit of load-based information sharing becomes more significant as communication capacity increases. It also suggests that multiparty communication plays an important role in forming/evolving team SMMs, and when a group of agents can be partitioned into subteams, splitting messages by their load status can be more effective for developing subteam SMMs.

  13. Mindstorms robots and the application of cognitive load theory in introductory programming

    NASA Astrophysics Data System (ADS)

    Mason, Raina; Cooper, Graham

    2013-12-01

    This paper reports on a series of introductory programming workshops, initially targeting female high school students, which utilised Lego Mindstorms robots. Cognitive load theory (CLT) was applied to the instructional design of the workshops, and a controlled experiment was also conducted investigating aspects of the interface. Results indicated that a truncated interface led to better learning by novice programmers as measured by test performance by participants, as well as enhanced shifts in self-efficacy and lowered perception of difficulty. There was also a transfer effect to another programming environment (Alice). It is argued that the results indicate that for novice programmers, the mere presence on-screen of additional (redundant) entities acts as a form of tacit distraction, thus impeding learning. The utility of CLT to analyse, design and deliver aspects of computer programming environments and instructional materials is discussed.

  14. Neural effects of cognitive control load on auditory selective attention.

    PubMed

    Sabri, Merav; Humphries, Colin; Verber, Matthew; Liebenthal, Einat; Binder, Jeffrey R; Mangalathu, Jain; Desai, Anjali

    2014-08-01

    Whether and how working memory disrupts or alters auditory selective attention is unclear. We compared simultaneous event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) responses associated with task-irrelevant sounds across high and low working memory load in a dichotic-listening paradigm. Participants performed n-back tasks (1-back, 2-back) in one ear (Attend ear) while ignoring task-irrelevant speech sounds in the other ear (Ignore ear). The effects of working memory load on selective attention were observed at 130-210ms, with higher load resulting in greater irrelevant syllable-related activation in localizer-defined regions in auditory cortex. The interaction between memory load and presence of irrelevant information revealed stronger activations primarily in frontal and parietal areas due to presence of irrelevant information in the higher memory load. Joint independent component analysis of ERP and fMRI data revealed that the ERP component in the N1 time-range is associated with activity in superior temporal gyrus and medial prefrontal cortex. These results demonstrate a dynamic relationship between working memory load and auditory selective attention, in agreement with the load model of attention and the idea of common neural resources for memory and attention.

  15. Very-low-frequency oscillations of cerebral hemodynamics and blood pressure are affected by aging and cognitive load.

    PubMed

    Vermeij, Anouk; Meel-van den Abeelen, Aisha S S; Kessels, Roy P C; van Beek, Arenda H E A; Claassen, Jurgen A H R

    2014-01-15

    Spontaneous slow oscillations occur in cerebral hemodynamics and blood pressure (BP), and may reflect neurogenic, metabolic or myogenic control of the cerebral vasculature. Aging is accompanied by a degeneration of the vascular system, which may have consequences for regional cerebral blood flow and cognitive performance. This degeneration may be reflected in a reduction of spontaneous slow oscillations of cerebral hemodynamics and BP. Therefore, we aimed to establish the dependency of slow oscillations of cerebral hemodynamics and BP on the factors age and cognitive load, by using functional near-infrared spectroscopy (fNIRS). Fourteen healthy young (23-32 years) and 14 healthy older adults (64-78 years) performed a verbal n-back working-memory task. Oxygenated and deoxygenated hemoglobin concentration changes were registered by two fNIRS channels located over left and right prefrontal cortex. BP was measured in the finger by photoplethysmography. We found that very-low-frequency oscillations (0.02-0.07 Hz) and low-frequency oscillations (0.07-0.2 Hz) of cerebral hemodynamics and BP were reduced in the older adults compared to the young during task performance. In young adults, very-low-frequency oscillations of cerebral hemodynamics and BP reduced with increased cognitive load. Cognitive load did not affect low-frequency oscillations of the cerebral hemodynamics and BP. Transfer function analysis indicated that the relationship between BP and cerebral hemodynamic oscillations does not change under influence of age and cognitive load. Our results suggest aging-related changes in the microvasculature such as declined spontaneous activity in microvascular smooth muscle cells and vessel stiffness. Moreover, our results indicate that in addition to local vasoregulatory processes, systemic processes also influence cerebral hemodynamic signals. It is therefore crucial to take the factors age and BP into consideration for the analysis and interpretation of hemodynamic

  16. Differential effects of cognitive load on emotion: Emotion maintenance versus passive experience.

    PubMed

    DeFraine, William C

    2016-06-01

    Two separate lines of research have examined the effects of cognitive load on emotional processing with similar tasks but seemingly contradictory results. Some research has shown that the emotions elicited by passive viewing of emotional images are reduced by subsequent cognitive load. Other research has shown that such emotions are not reduced by cognitive load if the emotions are actively maintained. The present study sought to compare and resolve these 2 lines of research. Participants either passively viewed negative emotional images or maintained the emotions elicited by the images, and after a delay rated the intensity of the emotion they were feeling. Half of trials included a math task during the delay to induce cognitive load, and the other half did not. Results showed that cognitive load reduced the intensity of negative emotions during passive-viewing of emotional images but not during emotion maintenance. The present study replicates the findings of both lines of research, and shows that the key factor is whether or not emotions are actively maintained. Also, in the context of previous emotion maintenance research, the present results support the theoretical idea of a separable emotion maintenance process. (PsycINFO Database Record

  17. The impact of cognitive control, incentives, and working memory load on the P3 responses of externalizing prisoners.

    PubMed

    Baskin-Sommers, Arielle R; Krusemark, Elizabeth A; Curtin, John J; Lee, Christopher; Vujnovich, Aleice; Newman, Joseph P

    2014-02-01

    The P3 amplitude reduction is one of the most common correlates of externalizing. However, few studies have used experimental manipulations designed to challenge different cognitive functions in order to clarify the processes that impact this reduction. To examine factors moderating P3 amplitude in trait externalizing, we administered an n-back task that manipulated cognitive control demands, working memory load, and incentives to a sample of male offenders. Offenders with high trait externalizing scores did not display a global reduction in P3 amplitude. Rather, the negative association between trait externalizing and P3 amplitude was specific to trials involving inhibition of a dominant response during infrequent stimuli, in the context of low working memory load, and incentives for performance. In addition, we discuss the potential implications of these findings for externalizing-related psychopathologies. The results complement and expand previous work on the process-level dysfunction contributing to externalizing-related deficits in P3.

  18. Additional helmet and pack loading reduce situational awareness during the establishment of marksmanship posture.

    PubMed

    Lim, Jongil; Palmer, Christopher J; Busa, Michael A; Amado, Avelino; Rosado, Luis D; Ducharme, Scott W; Simon, Darnell; Van Emmerik, Richard E A

    2016-09-03

    The pickup of visual information is critical for controlling movement and maintaining situational awareness in dangerous situations. Altered coordination while wearing protective equipment may impact the likelihood of injury or death. This investigation examined the consequences of load magnitude and distribution on situational awareness, segmental coordination and head gaze in several protective equipment ensembles. Twelve soldiers stepped down onto force plates and were instructed to quickly and accurately identify visual information while establishing marksmanship posture in protective equipment. Time to discriminate visual information was extended when additional pack and helmet loads were added, with the small increase in helmet load having the largest effect. Greater head-leading and in-phase trunk-head coordination were found with lighter pack loads, while trunk-leading coordination increased and head gaze dynamics were more disrupted in heavier pack loads. Additional armour load in the vest had no consequences for Time to discriminate, coordination or head dynamics. This suggests that the addition of head borne load be carefully considered when integrating new technology and that up-armouring does not necessarily have negative consequences for marksmanship performance. Practitioner Summary: Understanding the trade-space between protection and reductions in task performance continue to challenge those developing personal protective equipment. These methods provide an approach that can help optimise equipment design and loading techniques by quantifying changes in task performance and the emergent coordination dynamics that underlie that performance.

  19. Stroop-like effects in a new-code learning task: A cognitive load theory perspective.

    PubMed

    Hazan-Liran, Batel; Miller, Paul

    2017-09-01

    To determine whether and how learning is biased by competing task-irrelevant information that creates extraneous cognitive load, we assessed the efficiency of university students with a learning paradigm in two experiments. The paradigm asked participants to learn associations between eight words and eight digits. We manipulated congruity of the digits' ink colour with the words' semantics. In Experiment 1 word stimuli were colour words (e.g., blue, yellow) and in Experiment 2 colour-related word concepts (e.g., sky, banana). Marked benefits and costs on learning due to variation in extraneous cognitive load originating from processing task-irrelevant information were evident. Implications for cognitive load theory and schooling are discussed.

  20. The effects of captions on deaf students' content comprehension, cognitive load, and motivation in online learning.

    PubMed

    Yoon, Joong-O; Kim, Minjeong

    2011-01-01

    The authors examined the effects of captions on deaf students' content comprehension, cognitive load, and motivation in online learning. The participants in the study were 62 deaf adult students who had limited reading comprehension skills and used sign language as a first language. Participants were randomly assigned to either the control group or the experimental group. The independent variable was the presence of captions, and the dependent variables were content comprehension, cognitive load, and motivation. The study applied a posttest-only control group design. The results of the experiment indicated a significant difference (t = -2.16, p < .05) in content comprehension but no statistically significant difference in cognitive load and motivation between the two groups. These results led to suggestions for improvements in learning materials for deaf individuals.

  1. Cognitive Load and Self-Determination Theories Applied to E-Learning: Impact on Students' Participation and Academic Performance

    PubMed Central

    de Araujo Guerra Grangeia, Tiago; de Jorge, Bruno; Franci, Daniel; Martins Santos, Thiago; Vellutini Setubal, Maria Silvia; Schweller, Marcelo; de Carvalho-Filho, Marco Antonio

    2016-01-01

    Background Emergency clerkships expose students to a stressful environment that require multiple tasks, which may have a direct impact on cognitive load and motivation for learning. To address this challenge, Cognitive Load Theory and Self Determination Theory provided the conceptual frameworks to the development of a Moodle-based online Emergency Medicine course, inspired by real clinical cases. Methods Three consecutive classes (2013–2015) of sixth-year medical students (n = 304) participated in the course, during a curricular and essentially practical emergency rotation. “Virtual Rounds” provided weekly virtual patients in narrative format and meaningful schemata to chief complaints, in order to simulate real rounds at Emergency Unit. Additional activities such as Extreme Decisions, Emergency Quiz and Electrocardiographic challenge offered different views of emergency care. Authors assessed student´s participation and its correlation with their academic performance. A survey evaluated students´ opinions. Students graduating in 2015 answered an online questionnaire to investigate cognitive load and motivation. Results Each student produced 1965 pageviews and spent 72 hours logged on. Although Clinical Emergency rotation has two months long, students accessed the online course during an average of 5.3 months. Virtual Rounds was the most accessed activity, and there was positive correlations between the number of hours logged on the platform and final grades on Emergency Medicine. Over 90% of students felt an improvement in their clinical reasoning and considered themselves better prepared for rendering Emergency care. Considering a Likert scale from 1 (minimum load) to 7 (maximum load), the scores for total cognitive load were 4.79±2.2 for Virtual Rounds and 5.56±1.96 for real medical rounds(p<0,01). Conclusions A real-world inspired online course, based on cognitive and motivational conceptual frameworks, seems to be a strong tool to engage students in

  2. Power law scaling in synchronization of brain signals depends on cognitive load.

    PubMed

    Tinker, Jesse; Velazquez, Jose Luis Perez

    2014-01-01

    As it has several features that optimize information processing, it has been proposed that criticality governs the dynamics of nervous system activity. Indications of such dynamics have been reported for a variety of in vitro and in vivo recordings, ranging from in vitro slice electrophysiology to human functional magnetic resonance imaging. However, there still remains considerable debate as to whether the brain actually operates close to criticality or in another governing state such as stochastic or oscillatory dynamics. A tool used to investigate the criticality of nervous system data is the inspection of power-law distributions. Although the findings are controversial, such power-law scaling has been found in different types of recordings. Here, we studied whether there is a power law scaling in the distribution of the phase synchronization derived from magnetoencephalographic recordings during executive function tasks performed by children with and without autism. Characterizing the brain dynamics that is different between autistic and non-autistic individuals is important in order to find differences that could either aid diagnosis or provide insights as to possible therapeutic interventions in autism. We report in this study that power law scaling in the distributions of a phase synchrony index is not very common and its frequency of occurrence is similar in the control and the autism group. In addition, power law scaling tends to diminish with increased cognitive load (difficulty or engagement in the task). There were indications of changes in the probability distribution functions for the phase synchrony that were associated with a transition from power law scaling to lack of power law (or vice versa), which suggests the presence of phenomenological bifurcations in brain dynamics associated with cognitive load. Hence, brain dynamics may fluctuate between criticality and other regimes depending upon context and behaviors.

  3. Cognitive Performance and Physiological Changes under Heavy Load Carriage

    DTIC Science & Technology

    2010-07-01

    42 7 Table of Figures Figure 1. Projected scene of rural village providing linear perspective...infantryman (160 lbs.). Such loads can lead to injury, significant impact on mobility , and reduced likelihood of meeting mission objectives...less than the training weight to increase efficiency and mobility . More recent studies have suggested that weight carried could be significantly

  4. Apparatuses and methods of determining if a person operating equipment is experiencing an elevated cognitive load

    SciTech Connect

    Watkins, Michael L.; Keller, Paul Edwin; Amaya, Ivan A.

    2015-06-16

    A method of, and apparatus for, determining if a person operating equipment is experiencing an elevated cognitive load, wherein the person's use of a device at a first time is monitored so as to set a baseline signature. Then, at a later time, the person's use of the device is monitored to determine the person's performance at the second time, as represented by a performance signature. This performance signature can then be compared against the baseline signature to predict whether the person is experiencing an elevated cognitive load.

  5. The Effects of Load Carriage and Physical Fatigue on Cognitive Performance

    PubMed Central

    Eddy, Marianna D.; Hasselquist, Leif; Giles, Grace; Hayes, Jacqueline F.; Howe, Jessica; Rourke, Jennifer; Coyne, Megan; O’Donovan, Meghan; Batty, Jessica; Brunyé, Tad T.; Mahoney, Caroline R.

    2015-01-01

    In the current study, ten participants walked for two hours while carrying no load or a 40 kg load. During the second hour, treadmill grade was manipulated between a constant downhill or changing between flat, uphill, and downhill grades. Throughout the prolonged walk, participants performed two cognitive tasks, an auditory go no/go task and a visual target detection task. The main findings were that the number of false alarms increased over time in the loaded condition relative to the unloaded condition on the go no/go auditory task. There were also shifts in response criterion towards responding yes and decreased sensitivity in responding in the loaded condition compared to the unloaded condition. In the visual target detection there were no reliable effects of load carriage in the overall analysis however, there were slower reaction times in the loaded compared to unloaded condition during the second hour. PMID:26154515

  6. Teaching Gene Technology in an Outreach Lab: Students' Assigned Cognitive Load Clusters and the Clusters' Relationships to Learner Characteristics, Laboratory Variables, and Cognitive Achievement

    NASA Astrophysics Data System (ADS)

    Scharfenberg, Franz-Josef; Bogner, Franz X.

    2013-02-01

    This study classified students into different cognitive load (CL) groups by means of cluster analysis based on their experienced CL in a gene technology outreach lab which has instructionally been designed with regard to CL theory. The relationships of the identified student CL clusters to learner characteristics, laboratory variables, and cognitive achievement were examined using a pre-post-follow-up design. Participants of our day-long module Genetic Fingerprinting were 409 twelfth-graders. During the module instructional phases (pre-lab, theoretical, experimental, and interpretation phases), we measured the students' mental effort (ME) as an index of CL. By clustering the students' module-phase-specific ME pattern, we found three student CL clusters which were independent of the module instructional phases, labeled as low-level, average-level, and high-level loaded clusters. Additionally, we found two student CL clusters that were each particular to a specific module phase. Their members reported especially high ME invested in one phase each: within the pre-lab phase and within the interpretation phase. Differentiating the clusters, we identified uncertainty tolerance, prior experience in experimentation, epistemic interest, and prior knowledge as relevant learner characteristics. We found relationships to cognitive achievement, but no relationships to the examined laboratory variables. Our results underscore the importance of pre-lab and interpretation phases in hands-on teaching in science education and the need for teachers to pay attention to these phases, both inside and outside of outreach laboratory learning settings.

  7. Does performing drop jumps with additional eccentric loading improve jump performance?

    PubMed

    Aboodarda, Saied J; Byrne, Jeannette M; Samson, Michael; Wilson, Barry D; Mokhtar, Abdul H; Behm, David G

    2014-08-01

    Previous investigators have speculated that applying additional external load throughout the eccentric phase of the jumping movement could amplify the stretch-shortening cycle mechanism and modulate jumping performance and jump exercise intensity. The aims of this study, therefore, were to determine the effect of increased eccentric phase loading, as delivered using an elastic device, on drop jumps (DJs) performed from different drop heights. Of specific interest were changes in (a) the kinetics; eccentric and concentric impulse, rate of force development (RFD), concentric velocity and (b) the electromyographic (EMG) activity of leg muscles. In a randomized repeated-measure study, 15 highly resistance trained male subjects performed DJs from 3 heights (20, 35, and 50 cm) under 3 different conditions: body weight only (free DJ) and with elastic bands providing downward force equivalent to 20% (+20% DJ) and 30% (+30% DJ) of body mass. All DJs were recorded using video and force plate data that were synchronized with EMG data. Results demonstrated that using additional tensile load during the airborne and eccentric phases of the DJ could enhance eccentric impulse (p = 0.042) and RFD (p < 0.001) and resulted in small to moderate effect size (ES) increases in quadriceps intergrated EMG across the eccentric phase (0.23 > ES > 0.51). The observed greater eccentric loading, however, did not immediately alter concentric kinetics and jump height nor did it alter muscle activation levels during this phase. The findings indicated that, in addition to the conventional technique of increasing drop height, using a tensile load during the airborne and eccentric phases of the DJ could further improve eccentric loading of DJs. As it has been suggested that eccentric impulse and RFD are indicators of DJ exercise intensity, these findings suggest that the loaded DJs, using additional elastic load, may be an effective technique for improving DJ exercise intensity without acute effects

  8. [Influence Additional Cognitive Tasks on EEG Beta Rhythm Parameters during Forming and Testing Set to Perception of the Facial Expression].

    PubMed

    Yakovenko, I A; Cheremushkin, E A; Kozlov, M K

    2015-01-01

    The research of changes of a beta rhythm parameters on condition of working memory loading by extension of a interstimuli interval between the target and triggering stimuli to 16 sec is investigated on 70 healthy adults in two series of experiments with set to a facial expression. In the second series at the middle of this interval for strengthening of the load was entered the additional cognitive task in the form of conditioning stimuli like Go/NoGo--circles of blue or green color. Data analysis of the research was carried out by means of continuous wavelet-transformation on the basis of "mather" complex Morlet-wavelet in the range of 1-35 Hz. Beta rhythm power was characterized by the mean level, maxima of wavelet-transformation coefficient (WLC) and latent periods of maxima. Introduction of additional cognitive task to pause between the target and triggering stimuli led to essential increase in absolute values of the mean level of beta rhythm WLC and relative sizes of maxima of beta rhythm WLC. In the series of experiments without conditioning stimulus subjects with large number of mistakes (from 6 to 40), i.e. rigid set, in comparison with subjects with small number of mistakes (to 5), i.e. plastic set, at the forming stage were characterized by higher values of the mean level of beta rhythm WLC. Introduction of the conditioning stimuli led to smoothing of intergroup distinctions throughout the experiment.

  9. Cognitive Load Theory: A Broader View on the Role of Memory in Learning and Education

    ERIC Educational Resources Information Center

    Paas, Fred; Ayres, Paul

    2014-01-01

    According to cognitive load theory (CLT), the limitations of working memory (WM) in the learning of new tasks together with its ability to cooperate with an unlimited long-term memory (LTM) for familiar tasks enable human beings to deal effectively with complex problems and acquire highly complex knowledge and skills. With regard to WM, CLT has…

  10. Example-Based Learning in Heuristic Domains: A Cognitive Load Theory Account

    ERIC Educational Resources Information Center

    Renkl, Alexander; Hilbert, Tatjana; Schworm, Silke

    2009-01-01

    One classical instructional effect of cognitive load theory (CLT) is the worked-example effect. Although the vast majority of studies have focused on well-structured and algorithmic sub-domains of mathematics or physics, more recent studies have also analyzed learning with examples from complex domains in which only heuristic solution strategies…

  11. The Effects of Captions on Deaf Students' Content Comprehension, Cognitive Load, and Motivation in Online Learning

    ERIC Educational Resources Information Center

    Yoon, Joong-O.; Kim, Minjeong

    2011-01-01

    The authors examined the effects of captions on deaf students' content comprehension, cognitive load, and motivation in online learning. The participants in the study were 62 deaf adult students who had limited reading comprehension skills and used sign language as a first language. Participants were randomly assigned to either the control group…

  12. Instructional Benefits of Spoken Words: A Review of Cognitive Load Factors

    ERIC Educational Resources Information Center

    Kalyuga, Slava

    2012-01-01

    Spoken words have always been an important component of traditional instruction. With the development of modern educational technology tools, spoken text more often replaces or supplements written or on-screen textual representations. However, there could be a cognitive load cost involved in this trend, as spoken words can have both benefits and…

  13. Measuring Cognitive Load in Test Items: Static Graphics versus Animated Graphics

    ERIC Educational Resources Information Center

    Dindar, M.; Kabakçi Yurdakul, I.; Inan Dönmez, F.

    2015-01-01

    The majority of multimedia learning studies focus on the use of graphics in learning process but very few of them examine the role of graphics in testing students' knowledge. This study investigates the use of static graphics versus animated graphics in a computer-based English achievement test from a cognitive load theory perspective. Three…

  14. Effects of Computer-Based Visual Representation on Mathematics Learning and Cognitive Load

    ERIC Educational Resources Information Center

    Yung, Hsin I.; Paas, Fred

    2015-01-01

    Visual representation has been recognized as a powerful learning tool in many learning domains. Based on the assumption that visual representations can support deeper understanding, we examined the effects of visual representations on learning performance and cognitive load in the domain of mathematics. An experimental condition with visual…

  15. Cognitive Load Theory and the Effects of Transient Information on the Modality Effect

    ERIC Educational Resources Information Center

    Leahy, Wayne; Sweller, John

    2016-01-01

    Based on cognitive load theory and the "transient information effect," this paper investigated the "modality effect" while interpreting a contour map. The length and complexity of auditory and visual text instructions were manipulated. Experiment 1 indicated that longer audio text information within a presentation was inferior…

  16. Effects of Cueing by a Pedagogical Agent in an Instructional Animation: A Cognitive Load Approach

    ERIC Educational Resources Information Center

    Yung, Hsin I.; Paas, Fred

    2015-01-01

    This study investigated the effects of a pedagogical agent that cued relevant information in a story-based instructional animation on the cardiovascular system. Based on cognitive load theory, it was expected that the experimental condition with the pedagogical agent would facilitate students to distinguish between relevant and irrelevant…

  17. Optimizing Cognitive Load for Learning from Computer-Based Science Simulations

    ERIC Educational Resources Information Center

    Lee, Hyunjeong; Plass, Jan L.; Homer, Bruce D.

    2006-01-01

    How can cognitive load in visual displays of computer simulations be optimized? Middle-school chemistry students (N = 257) learned with a simulation of the ideal gas law. Visual complexity was manipulated by separating the display of the simulations in two screens (low complexity) or presenting all information on one screen (high complexity). The…

  18. Assessing Cognitive Load Theory to Improve Student Learning for Mechanical Engineers

    ERIC Educational Resources Information Center

    Impelluso, Thomas J.

    2009-01-01

    A computer programming class for students of mechanical engineering was redesigned and assessed: Cognitive Load Theory was used to redesign the content; online technologies were used to redesign the delivery. Student learning improved and the dropout rate was reduced. This article reports on both attitudinal and objective assessment: comparing…

  19. Unpacking the Complexity of Linear Equations from a Cognitive Load Theory Perspective

    ERIC Educational Resources Information Center

    Ngu, Bing Hiong; Phan, Huy P.

    2016-01-01

    The degree of element interactivity determines the complexity and therefore the intrinsic cognitive load of linear equations. The unpacking of linear equations at the level of operational and relational lines allows the classification of linear equations in a hierarchical level of complexity. Mapping similar operational and relational lines across…

  20. Cognitive Load of Navigating without Vision when Guided by Virtual Sound versus Spatial Language

    ERIC Educational Resources Information Center

    Klatzky, Roberta L.; Marston, James R.; Giudice, Nicholas A.; Golledge, Reginald G.; Loomis, Jack M.

    2006-01-01

    A vibrotactile N-back task was used to generate cognitive load while participants were guided along virtual paths without vision. As participants stepped in place, they moved along a virtual path of linear segments. Information was provided en route about the direction of the next turning point, by spatial language ("left," "right," or "straight")…

  1. Manipulation of Cognitive Load Variables and Impact on Auscultation Test Performance

    ERIC Educational Resources Information Center

    Chen, Ruth; Grierson, Lawrence; Norman, Geoffrey

    2015-01-01

    Health profession educators have identified auscultation skill as a learning need for health professional students. This article explores the application of cognitive load theory (CLT) to designing cardiac and respiratory auscultation skill instruction for senior-level undergraduate nursing students. Three experiments assessed student auscultation…

  2. The Effects of Communication Modality on Presence, Cognitive Load and Retention in Second Life

    ERIC Educational Resources Information Center

    Wilkes, Stephany Filimon

    2009-01-01

    This thesis reports findings from a study (N = 60) of the impact of three communication modalities (voice only, text only, and voice and text simultaneously) on cognitive load, as measured by subjective reports of mental effort; on learning, as measured by tests of recall and retention; and on perceptions of presence as measured by a Presence…

  3. The Beast of Aggregating Cognitive Load Measures in Technology-Based Learning

    ERIC Educational Resources Information Center

    Leppink, Jimmie; van Merriënboer, Jeroen J. G.

    2015-01-01

    An increasing part of cognitive load research in technology-based learning includes a component of repeated measurements, that is: participants are measured two or more times on the same performance, mental effort or other variable of interest. In many cases, researchers aggregate scores obtained from repeated measurements to one single sum or…

  4. An Analysis of Eye Movement and Cognitive Load about the Editorial Design in Elementary Science Textbook

    ERIC Educational Resources Information Center

    Kim, Seong-un; Lim, Sung-man; Kim, Eun-ae; Yang, Il-ho

    2016-01-01

    This study is for the implication of editorial design in science textbooks which are designed for student-centered instruction, when the elements of the editorial design are different, we focus on how the students' eye movement and cognitive load change. For this, we produced a new book for 5th grade students in elementary school that is modified…

  5. Effects of Multimedia on Cognitive Load, Self-Efficacy, and Multiple Rule-Based Problem Solving

    ERIC Educational Resources Information Center

    Zheng, Robert; McAlack, Matthew; Wilmes, Barbara; Kohler-Evans, Patty; Williamson, Jacquee

    2009-01-01

    This study investigates effects of multimedia on cognitive load, self-efficacy and learners' ability to solve multiple rule-based problems. Two hundred twenty-two college students were randomly assigned to interactive and non-interactive multimedia groups. Based on Engelkamp's multimodal theory, the present study investigates the role of…

  6. Leveraging Cognitive Load Theory, Scaffolding, and Distance Technologies to Enhance Computer Programming for Non-Majors

    ERIC Educational Resources Information Center

    Impelluso, Thomas J.

    2009-01-01

    Cognitive Load Theory (CLT) was used as a foundation to redesign a computer programming class for mechanical engineers, in which content was delivered with hybrid/distance technology. The effort confirmed the utility of CLT in course design. And it demonstrates that hybrid/distance learning is not merely a tool of convenience, but one, which, when…

  7. Effects of Prior Knowledge and Concept-Map Structure on Disorientation, Cognitive Load, and Learning

    ERIC Educational Resources Information Center

    Amadieu, Franck; van Gog, Tamara; Paas, Fred; Tricot, Andre; Marine, Claudette

    2009-01-01

    This study explored the effects of prior knowledge (high vs. low; HPK and LPK) and concept-map structure (hierarchical vs. network; HS and NS) on disorientation, cognitive load, and learning from non-linear documents on "the infection process of a retrograde virus (HIV)". Participants in the study were 24 adults. Overall subjective ratings of…

  8. Measuring Cognitive Load with Subjective Rating Scales during Problem Solving: Differences between Immediate and Delayed Ratings

    ERIC Educational Resources Information Center

    Schmeck, Annett; Opfermann, Maria; van Gog, Tamara; Paas, Fred; Leutner, Detlev

    2015-01-01

    Subjective cognitive load (CL) rating scales are widely used in educational research. However, there are still some open questions regarding the point of time at which such scales should be applied. Whereas some studies apply rating scales directly after each step or task and use an average of these ratings, others assess CL only once after the…

  9. Interactivity of Question Prompts and Feedback on Secondary Students' Science Knowledge Acquisition and Cognitive Load

    ERIC Educational Resources Information Center

    Huang, Kun; Chen, Ching-Huei; Wu, Wen-Shiuan; Chen, Wei-Yu

    2015-01-01

    This study investigated how question prompts and feedback influenced knowledge acquisition and cognitive load when learning Newtonian mechanics within a web-based multimedia module. Participants were one hundred eighteen 9th grade students who were randomly assigned to one of four experimental conditions, forming a 2 x 2 factorial design with the…

  10. Applying Cognitive Load Theory to the Redesign of a Conventional Database Systems Course

    ERIC Educational Resources Information Center

    Mason, Raina; Seton, Carolyn; Cooper, Graham

    2016-01-01

    Cognitive load theory (CLT) was used to redesign a Database Systems course for Information Technology students. The redesign was intended to address poor student performance and low satisfaction, and to provide a more relevant foundation in database design and use for subsequent studies and industry. The original course followed the conventional…

  11. Does Instructional Format Really Matter? Cognitive Load Theory, Multimedia and Teaching English Literature

    ERIC Educational Resources Information Center

    Martin, Stewart

    2012-01-01

    This article reports a quasi-experimental study on the effects of multimedia teaching and learning in English Literature--a subject which places high cognitive load on students. A large-scale study was conducted in 4 high-achieving secondary schools to examine the differences made to students' learning and performance by the use of multimedia and…

  12. How Can One Learn Mathematical Word Problems in a Second Language? A Cognitive Load Perspective

    ERIC Educational Resources Information Center

    Moussa-Inaty, Jase; Causapin, Mark; Groombridge, Timothy

    2015-01-01

    Language may ordinarily account for difficulties in solving word problems and this is particularly true if mathematical word problems are taught in a language other than one's native language. Research into cognitive load may offer a clear theoretical framework when investigating word problems because memory, specifically working memory, plays a…

  13. Mindstorms Robots and the Application of Cognitive Load Theory in Introductory Programming

    ERIC Educational Resources Information Center

    Mason, Raina; Cooper, Graham

    2013-01-01

    This paper reports on a series of introductory programming workshops, initially targeting female high school students, which utilised Lego Mindstorms robots. Cognitive load theory (CLT) was applied to the instructional design of the workshops, and a controlled experiment was also conducted investigating aspects of the interface. Results indicated…

  14. Using Cognitive Load Theory to Tailor Instruction to Levels of Accounting Students' Expertise

    ERIC Educational Resources Information Center

    Blayney, Paul; Kalyuga, Slava; Sweller, John

    2015-01-01

    Tailoring of instructional methods to learner levels of expertise may reduce extraneous cognitive load and improve learning. Contemporary technology-based learning environments have the potential to substantially enable learner-adapted instruction. This paper investigates the effects of adaptive instruction based on using the isolated-interactive…

  15. Overloading on Slides: Cognitive Load Theory and Microsoft's Slide Program PowerPoint

    ERIC Educational Resources Information Center

    Cooper, Elizabeth

    2009-01-01

    The integration of Microsoft's PowerPoint and other slideware programs into the classroom setting may hinder educational progress rather than help it. An examination of the literature focusing on Cognitive Load Theory recognizes that students' have a limited tolerance for the amount of sights and sounds on display at any given time, especially in…

  16. Examining Hypermedia Learning: The Role of Cognitive Load and Self-Regulated Learning

    ERIC Educational Resources Information Center

    Moos, Daniel

    2013-01-01

    Distinct theoretical perspectives, Cognitive Load Theory and Self-Regulated Learning (SRL) theory, have been used to examine individual differences the challenges faced with hypermedia learning. However, research has tended to use these theories independently, resulting in less robust explanations of hypermedia learning. This study examined the…

  17. Exploring Effects of Background Context Familiarity and Signaling on Comprehension, Recall, and Cognitive Load

    ERIC Educational Resources Information Center

    Song, Minjung; Bruning, Roger

    2016-01-01

    This study was designed to explore the effects of different geographical background contexts and signalling for information about global warming on comprehension, recall and cognitive load. Two different geographical contexts, US and Korean, were employed to frame explanations of global warming phenomena to US students. Two signalling conditions…

  18. The Effects of Electronic Portfolio Tools on Online Students' Perceived Support and Cognitive Load

    ERIC Educational Resources Information Center

    Shepherd, Craig E.; Bolliger, Doris U.

    2011-01-01

    Although distance educators are adopting electronic portfolios (eportfolios) for purposes of assessment and collaboration, some researchers question their utility in these venues. In a setting where feelings of isolation and attrition are high, this study examined how eportfolios affect cognitive load and student perceptions of support. The study…

  19. Managing Cognitive Load in Educational Multi-User Virtual Environments: Reflection on Design Practice

    ERIC Educational Resources Information Center

    Nelson, Brian C.; Erlandson, Benjamin E.

    2008-01-01

    In this paper, we explore how the application of multimedia design principles may inform the development of educational multi-user virtual environments (MUVEs). We look at design principles that have been shown to help learners manage cognitive load within multimedia environments and conduct a conjectural analysis of the extent to which such…

  20. The Effect of Hypertext Annotation Presentation Formats on Perceived Cognitive Load and Learner Control

    ERIC Educational Resources Information Center

    Yao, Yuanming; Gill, Michele

    2009-01-01

    The impact of hypertext presentation formats on learner control and cognitive load was examined in this study using Campbell and Stanley's (1963) Posttest Only Control Group design. One hundred eighty-six undergraduate students were randomly assigned to read a web-based text with no annotations, online glossary annotations, embedded annotations,…

  1. Exploring the Cognitive Loads of High-School Students as They Learn Concepts in Web-Based Environments

    ERIC Educational Resources Information Center

    Chang, Cheng-Chieh; Yang, Fang-Ying

    2010-01-01

    This study measured high-school learners' cognitive load as they interacted with different web-based curriculum components, and examined the interactions between cognitive load and web-based concept learning. Participants in this study were 105 11th graders from an academic senior high school in Taiwan. An online, multimedia curriculum on the…

  2. Measuring Cognitive Load during Simulation-Based Psychomotor Skills Training: Sensitivity of Secondary-Task Performance and Subjective Ratings

    ERIC Educational Resources Information Center

    Haji, Faizal A.; Khan, Rabia; Regehr, Glenn; Drake, James; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-01-01

    As interest in applying cognitive load theory (CLT) to the study and design of pedagogic and technological approaches in healthcare simulation grows, suitable measures of cognitive load (CL) are needed. Here, we report a two-phased study investigating the sensitivity of subjective ratings of mental effort (SRME) and secondary-task performance…

  3. Self-Instructional Module Based on Cognitive Load Theory: A Study on Information Retention among Trainee Teachers

    ERIC Educational Resources Information Center

    Ong, Chiek Pin; Tasir, Zaidatun

    2015-01-01

    The aim of the research is to study the information retention among trainee teachers using a self-instructional printed module based on Cognitive Load Theory for learning spreadsheet software. Effective pedagogical considerations integrating the theoretical concepts related to cognitive load are reflected in the design and development of the…

  4. Sound as Affective Design Feature in Multimedia Learning--Benefits and Drawbacks from a Cognitive Load Theory Perspective

    ERIC Educational Resources Information Center

    Königschulte, Anke

    2015-01-01

    The study presented in this paper investigates the potential effects of including non-speech audio such as sound effects into multimedia-based instruction taking into account Sweller's cognitive load theory (Sweller, 2005) and applied frameworks such as the cognitive theory of multimedia learning (Mayer, 2005) and the cognitive affective theory of…

  5. The effects of food advertising and cognitive load on food choices

    PubMed Central

    2014-01-01

    Background Advertising has been implicated in the declining quality of the American diet, but much of the research has been conducted with children rather than adults. This study tested the effects of televised food advertising on adult food choice. Methods Participants (N = 351) were randomized into one of 4 experimental conditions: exposure to food advertising vs. exposure to non-food advertising, and within each of these groups, exposure to a task that was either cognitively demanding or not cognitively demanding. The number of unhealthy snacks chosen was subsequently measured, along with total calories of the snacks chosen. Results Those exposed to food advertising chose 28% more unhealthy snacks than those exposed to non-food-advertising (95% CI: 7% - 53%), with a total caloric value that was 65 kcal higher (95% CI: 10-121). The effect of advertising was not significant among those assigned to the low-cognitive-load group, but was large and significant among those assigned to the high-cognitive-load group: 43% more unhealthy snacks (95% CI: 11% - 85%) and 94 more total calories (95% CI: 19-169). Conclusions Televised food advertising has strong effects on individual food choice, and these effects are magnified when individuals are cognitively occupied by other tasks. PMID:24721289

  6. How a patent ductus arteriosus effects the premature lamb's ability to handle additional volume loads.

    PubMed

    Clyman, R I; Roman, C; Heymann, M A; Mauray, F

    1987-11-01

    A model of patent ductus arteriosus in premature lambs was created to examine the lamb's ability to handle the volume load imposed by a patent ductus arteriosus and to determine the lamb's ability to handle any additional volume load. Fifteen preterm lambs [133 +/- 2 (+/- SD) days gestation, term 145 days], whose ductal diameter could be regulated with a mechanical occluder, were studied to determine the independent effects of ductus patency and a saline volume load (50 ml/kg over 3 min) on left ventricular output and its distribution. During a saline infusion, preterm lambs with a closed ductus could only increase their stroke volume by 40% above baseline stroke volume. When challenged with a saline infusion, lambs with an open ductus still were able to increase their stroke volume significantly; the maximal increase in stroke volume during the saline load with the ductus open was 70% above baseline stroke volume. We hypothesize that the associated reduced left ventricular afterload plays a significant role in the preterm lamb's ability to increase its stroke volume when challenged with a patent ductus arteriosus. Even with a patent ductus arteriosus, the lamb still has the ability to handle additional volume loads.

  7. Reducing cognitive load in the chemistry laboratory by using technology-driven guided inquiry experiments

    NASA Astrophysics Data System (ADS)

    Hubacz, Frank, Jr.

    The chemistry laboratory is an integral component of the learning experience for students enrolled in college-level general chemistry courses. Science education research has shown that guided inquiry investigations provide students with an optimum learning environment within the laboratory. These investigations reflect the basic tenets of constructivism by engaging students in a learning environment that allows them to experience what they learn and to then construct, in their own minds, a meaningful understanding of the ideas and concepts investigated. However, educational research also indicates that the physical plant of the laboratory environment combined with the procedural requirements of the investigation itself often produces a great demand upon a student's working memory. This demand, which is often superfluous to the chemical concept under investigation, creates a sensory overload or extraneous cognitive load within the working memory and becomes a significant obstacle to student learning. Extraneous cognitive load inhibits necessary schema formation within the learner's working memory thereby impeding the transfer of ideas to the learner's long-term memory. Cognitive Load Theory suggests that instructional material developed to reduce extraneous cognitive load leads to an improved learning environment for the student which better allows for schema formation. This study first compared the cognitive load demand, as measured by mental effort, experienced by 33 participants enrolled in a first-year general chemistry course in which the treatment group, using technology based investigations, and the non-treatment group, using traditional labware, investigated identical chemical concepts on five different exercises. Mental effort was measured via a mental effort survey, a statistical comparison of individual survey results to a procedural step count, and an analysis of fourteen post-treatment interviews. Next, a statistical analysis of achievement was

  8. Lesion Load May Predict Long-Term Cognitive Dysfunction in Multiple Sclerosis Patients

    PubMed Central

    Lavorgna, Luigi; Messina, Silvia; Chisari, Clara Grazia; Ippolito, Domenico; Lanzillo, Roberta; Vacchiano, Veria; Realmuto, Sabrina; Valentino, Paola; Coniglio, Gabriella; Buccafusca, Maria; Paolicelli, Damiano; D’Ambrosio, Alessandro; Montella, Patrizia; Brescia Morra, Vincenzo; Savettieri, Giovanni; Alfano, Bruno; Gallo, Antonio; Simone, Isabella; Viterbo, Rosa; Zappia, Mario; Bonavita, Simona; Tedeschi, Gioacchino

    2015-01-01

    Background Magnetic Resonance Imaging (MRI) techniques provided evidences into the understanding of cognitive impairment (CIm) in Multiple Sclerosis (MS). Objectives To investigate the role of white matter (WM) and gray matter (GM) in predicting long-term CIm in a cohort of MS patients. Methods 303 out of 597 patients participating in a previous multicenter clinical-MRI study were enrolled (49.4% were lost at follow-up). The following MRI parameters, expressed as fraction (f) of intracranial volume, were evaluated: cerebrospinal fluid (CSF-f), WM-f, GM-f and abnormal WM (AWM-f), a measure of lesion load. Nine years later, cognitive status was assessed in 241 patients using the Symbol Digit Modalities Test (SDMT), the Semantically Related Word List Test (SRWL), the Modified Card Sorting Test (MCST), and the Paced Auditory Serial Addition Test (PASAT). In particular, being SRWL a memory test, both immediate recall and delayed recall were evaluated. MCST scoring was calculated based on the number of categories, number of perseverative and non-perseverative errors. Results AWM-f was predictive of an impaired performance 9 years ahead in SDMT (OR 1.49, CI 1.12–1.97 p = 0.006), PASAT (OR 1.43, CI 1.14–1.80 p = 0.002), SRWL-immediate recall (OR 1.72 CI 1.35–2.20 p<0.001), SRWL-delayed recall (OR 1.61 CI 1.28–2.03 p<0.001), MCST-category (OR 1.52, CI 1.2–1.9 p<0.001), MCST-perseverative error(OR 1.51 CI 1.2–1.9 p = 0.001), MCST-non perseverative error (OR 1.26 CI 1.02–1.55 p = 0.032). Conclusion In our large MS cohort, focal WM damage appeared to be the most relevant predictor of the long-term cognitive outcome. PMID:25816303

  9. Preventing information overload: cognitive load theory as an instructional framework for teaching pharmacology.

    PubMed

    Kaylor, Sara K

    2014-02-01

    Nursing students are challenged by content-laden curricula and learning environments that emphasize testing outcomes. Likewise, educators are challenged to support student-centered learning in a manner that encourages students to connect and act upon their personal motivations. This article describes the use of cognitive load theory (CLT) as an instructional design framework for an undergraduate pharmacology for nursing course. Guided by the principles of CLT, four instructional strategies were used in this course: (a) opening review activities, (b) providing students with lecture notes, (c) a "Top Five" prototype approach, and (d) deciphering "Need to Knows" from "Nice to Knows." Instructional style and strategies received positive student feedback and were found to promote a student-centered environment and active learning. On the basis of this feedback, cognitive load theory may be a successful and effective framework for undergraduate pharmacology and other nursing courses, thus assisting students and educators alike in overcoming obstacles imposed on learning environments.

  10. Optimizing physicians' instruction of PACS through e-learning: cognitive load theory applied.

    PubMed

    Devolder, P; Pynoo, B; Voet, T; Adang, L; Vercruysse, J; Duyck, P

    2009-03-01

    This article outlines the strategy used by our hospital to maximize the knowledge transfer to referring physicians on using a picture archiving and communication system (PACS). We developed an e-learning platform underpinned by the cognitive load theory (CLT) so that in depth knowledge of PACS' abilities becomes attainable regardless of the user's prior experience with computers. The application of the techniques proposed by CLT optimizes the learning of the new actions necessary to obtain and manipulate radiological images. The application of cognitive load reducing techniques is explained with several examples. We discuss the need to safeguard the physicians' main mental processes to keep the patient's interests in focus. A holistic adoption of CLT techniques both in teaching and in configuration of information systems could be adopted to attain this goal. An overview of the advantages of this instruction method is given both on the individual and organizational level.

  11. Eye closure helps memory by reducing cognitive load and enhancing visualisation.

    PubMed

    Vredeveldt, Annelies; Hitch, Graham J; Baddeley, Alan D

    2011-10-01

    Closing the eyes helps memory. We investigated the mechanisms underlying the eyeclosure effect by exposing 80 eyewitnesses to different types of distraction during the witness interview: blank screen (control), eyes closed, visual distraction, and auditory distraction. We examined the cognitive load hypothesis by comparing any type of distraction (visual or auditory) with minimal distraction (blank screen or eyes closed). We found recall to be significantly better when distraction was minimal, providing evidence that eyeclosure reduces cognitive load. We examined the modality-specific interference hypothesis by comparing the effects of visual and auditory distraction on recall of visual and auditory information. Visual and auditory distraction selectively impaired memory for information presented in the same modality, supporting the role of visualisation in the eyeclosure effect. Analysis of recall in terms of grain size revealed that recall of basic information about the event was robust, whereas recall of specific details was prone to both general and modality-specific disruptions.

  12. Cognitive load imposed by ultrasound-facilitated teaching does not adversely affect gross anatomy learning outcomes.

    PubMed

    Jamniczky, Heather A; Cotton, Darrel; Paget, Michael; Ramji, Qahir; Lenz, Ryan; McLaughlin, Kevin; Coderre, Sylvain; Ma, Irene W Y

    2017-03-01

    Ultrasonography is increasingly used in medical education, but its impact on learning outcomes is unclear. Adding ultrasound may facilitate learning, but may also potentially overwhelm novice learners. Based upon the framework of cognitive load theory, this study seeks to evaluate the relationship between cognitive load associated with using ultrasound and learning outcomes. The use of ultrasound was hypothesized to facilitate learning in anatomy for 161 novice first-year medical students. Using linear regression analyses, the relationship between reported cognitive load on using ultrasound and learning outcomes as measured by anatomy laboratory examination scores four weeks after ultrasound-guided anatomy training was evaluated in consenting students. Second anatomy examination scores of students who were taught anatomy with ultrasound were compared with historical controls (those not taught with ultrasound). Ultrasound's perceived utility for learning was measured on a five-point scale. Cognitive load on using ultrasound was measured on a nine-point scale. Primary outcome was the laboratory examination score (60 questions). Learners found ultrasound useful for learning. Weighted factor score on "image interpretation" was negatively, but insignificantly, associated with examination scores [F (1,135) = 0.28, beta = -0.22; P = 0.61]. Weighted factor score on "basic knobology" was positively and insignificantly associated with scores; [F (1,138) = 0.27, beta = 0.42; P = 0.60]. Cohorts exposed to ultrasound had significantly higher scores than historical controls (82.4% ± SD 8.6% vs. 78.8% ± 8.5%, Cohen's d = 0.41, P < 0.001). Using ultrasound to teach anatomy does not negatively impact learning and may improve learning outcomes. Anat Sci Educ 10: 144-151. © 2016 American Association of Anatomists.

  13. Pupil diameter as predictor of cognitive load: A novel tool for geoscience education research

    NASA Astrophysics Data System (ADS)

    Mitra, R.; McNeal, K.

    2015-12-01

    Pupils can truly serve as windows to the mind. Since the early part of the last decade, pupillometry, the study of pupils in response to cognitive tasks, have gained traction in psychophysiological studies. Muscles of the iris work in tandem with the autonomic nervous system in response to light condition to either dilate or contract the pupil, usually between 2 to 7 mm. Along with this response to light conditions, the pupils also contract or dilate in response to emotional or mental response. Therefore, for a cognitive task, if the ambient brightness is controlled, pupil dilation reflects the cognitive load associated with the task. Simple tasks such as counting, memorizing, multiplying and visual searching have been found to have pupillometry profiles reflective of the cognitive load involved with such tasks. In this study, we investigate whether pupil diameter can be used for education research where tasks can be more complex. In particular, we look at two specific types of tasks common in geoscience and several other STEM fields: graph reading and spatial problem solving.

  14. Cognitive Load Differentially Impacts Response Control in Girls and Boys with ADHD

    PubMed Central

    Mostofsky, Stewart H.; Rosch, Keri S.

    2015-01-01

    Children with attention-deficit hyperactivity disorder (ADHD) consistently show impaired response control, including deficits in response inhibition and increased intrasubject variability (ISV) compared to typically-developing (TD) children. However, significantly less research has examined factors that may influence response control in individuals with ADHD, such as task or participant characteristics. The current study extends the literature by examining the impact of increasing cognitive demands on response control in a large sample of 81children with ADHD (40 girls) and 100 TD children (47 girls), ages 8–12 years. Participants completed a simple Go/No-Go (GNG) task with minimal cognitive demands, and a complex GNG task with increased cognitive load. Results showed that increasing cognitive load differentially impacted response control (commission error rate and tau, an ex-Gaussian measure of ISV) for girls, but not boys, with ADHD compared to same-sex TD children. Specifically, a sexually dimorphic pattern emerged such that boys with ADHD demonstrated higher commission error rate and tau on both the simple and complex GNG tasks as compared to TD boys, whereas girls with ADHD did not differ from TD girls on the simple GNG task, but showed higher commission error rate and tau on the complex GNG task. These findings suggest that task complexity influences response control in children with ADHD in a sexually dimorphic manner. The findings have substantive implications for the pathophysiology of ADHD in boys versus girls with ADHD. PMID:25624066

  15. Load bearing and stiffness tailored NiTi implants produced by additive manufacturing: a simulation study

    NASA Astrophysics Data System (ADS)

    Rahmanian, Rasool; Shayesteh Moghaddam, Narges; Haberland, Christoph; Dean, David; Miller, Michael; Elahinia, Mohammad

    2014-03-01

    Common metals for stable long-term implants (e.g. stainless steel, Titanium and Titanium alloys) are much stiffer than spongy cancellous and even stiffer than cortical bone. When bone and implant are loaded this stiffness mismatch results in stress shielding and as a consequence, degradation of surrounding bony structure can lead to disassociation of the implant. Due to its lower stiffness and high reversible deformability, which is associated with the superelastic behavior, NiTi is an attractive biomaterial for load bearing implants. However, the stiffness of austenitic Nitinol is closer to that of bone but still too high. Additive manufacturing provides, in addition to the fabrication of patient specific implants, the ability to solve the stiffness mismatch by adding engineered porosity to the implant. This in turn allows for the design of different stiffness profiles in one implant tailored to the physiological load conditions. This work covers a fundamental approach to bring this vision to reality. At first modeling of the mechanical behavior of different scaffold designs are presented as a proof of concept of stiffness tailoring. Based on these results different Nitinol scaffolds can be produced by additive manufacturing.

  16. Revival of pure titanium for dynamically loaded porous implants using additive manufacturing.

    PubMed

    Wauthle, Ruben; Ahmadi, Seyed Mohammad; Amin Yavari, Saber; Mulier, Michiel; Zadpoor, Amir Abbas; Weinans, Harrie; Van Humbeeck, Jan; Kruth, Jean-Pierre; Schrooten, Jan

    2015-09-01

    Additive manufacturing techniques are getting more and more established as reliable methods for producing porous metal implants thanks to the almost full geometrical and mechanical control of the designed porous biomaterial. Today, Ti6Al4V ELI is still the most widely used material for porous implants, and none or little interest goes to pure titanium for use in orthopedic or load-bearing implants. Given the special mechanical behavior of cellular structures and the material properties inherent to the additive manufacturing of metals, the aim of this study is to investigate the properties of selective laser melted pure unalloyed titanium porous structures. Therefore, the static and dynamic compressive properties of pure titanium structures are determined and compared to previously reported results for identical structures made from Ti6Al4V ELI and tantalum. The results show that porous Ti6Al4V ELI still remains the strongest material for statically loaded applications, whereas pure titanium has a mechanical behavior similar to tantalum and is the material of choice for cyclically loaded porous implants. These findings are considered to be important for future implant developments since it announces a potential revival of the use of pure titanium for additively manufactured porous implants.

  17. Using Perspective to Resolve Reference: The Impact of Cognitive Load and Motivation.

    PubMed

    Cane, James E; Ferguson, Heather J; Apperly, Ian A

    2017-01-09

    Research has demonstrated a link between perspective taking and working memory. Here we used eye tracking to examine the time course with which working memory load (WML) influences perspective-taking ability in a referential communication task and how motivation to take another's perspective modulates these effects. In Experiment 1, where there was no reward or time pressure, listeners only showed evidence of incorporating perspective knowledge during integration of the target object but did not anticipate reference to this common ground object during the pretarget-noun period. WML did not affect this perspective use. In Experiment 2, where a reward for speed and accuracy was applied, listeners used perspective cues to disambiguate the target object from the competitor object from the earliest moments of processing (i.e., during the pretarget-noun period), but only under low load. Under high load, responses were comparable with the control condition, where both objects were in common ground. Furthermore, attempts to initiate perspective-relevant responses under high load led to impaired recall on the concurrent WML task, indicating that perspective-relevant responses were drawing on limited cognitive resources. These results show that when there is ambiguity, perspective cues guide rapid referential interpretation when there is sufficient motivation and sufficient cognitive resources. (PsycINFO Database Record

  18. A cognition-based method to ease the computational load for an extended Kalman filter.

    PubMed

    Li, Yanpeng; Li, Xiang; Deng, Bin; Wang, Hongqiang; Qin, Yuliang

    2014-12-03

    The extended Kalman filter (EKF) is the nonlinear model of a Kalman filter (KF). It is a useful parameter estimation method when the observation model and/or the state transition model is not a linear function. However, the computational requirements in EKF are a difficulty for the system. With the help of cognition-based designation and the Taylor expansion method, a novel algorithm is proposed to ease the computational load for EKF in azimuth predicting and localizing under a nonlinear observation model. When there are nonlinear functions and inverse calculations for matrices, this method makes use of the major components (according to current performance and the performance requirements) in the Taylor expansion. As a result, the computational load is greatly lowered and the performance is ensured. Simulation results show that the proposed measure will deliver filtering output with a similar precision compared to the regular EKF. At the same time, the computational load is substantially lowered.

  19. Improvement of activated sludge resistance to shock loading by fungal enzyme addition during textile wastewater treatment.

    PubMed

    Manai, Imène; Miladi, Baligh; El Mselmi, Abdellatif; Hamdi, Moktar; Bouallagui, Hassib

    2017-04-01

    The effects of the additions of the fungal enzymatic extract were investigated in relation to the treatment of real textile wastewater (RTW) by the activated sludge process (ASP). The used enzyme cocktail was produced by a new isolated fungal Chaetomium globosum IMA1. The system that was operated with enzyme addition showed a better chemical oxygen demand (COD) removal efficiency (95%) compared to the control system (75%). In addition, the improvement of color removal (OD620) efficiencies was around 15%, when the newly consortium fungal enzymes was added. As the organic loading rate (OLR) increased from 0.33 g to 0.66 g COD L(-1) d(-1), a decrease in the performance of the two reactors was observed by monitoring the quality of treated effluents. However, the ASP working with enzyme addition showed a strong resistance to shock loadings and restored after few days compared to the control system, which was strongly inhibited. In fact, the enzyme addition improved the sludge volume index (SVI) and the activity of microorganisms. A high activity of laccase (300 U.L(-1)) enzyme was observed throughout the decolorization process in the improved system.

  20. Cognitive task load in a naval ship control centre: from identification to prediction.

    PubMed

    Grootjen, M; Neerincx, M A; Veltman, J A

    Deployment of information and communication technology will lead to further automation of control centre tasks and an increasing amount of information to be processed. A method for establishing adequate levels of cognitive task load for the operators in such complex environments has been developed. It is based on a model distinguishing three load factors: time occupied, task-set switching, and level of information processing. Application of the method resulted in eight scenarios for eight extremes of task load (i.e. low and high values for each load factor). These scenarios were performed by 13 teams in a high-fidelity control centre simulator of the Royal Netherlands Navy. The results show that the method provides good prediction of the task load that will actually appear in the simulator. The model allowed identification of under- and overload situations showing negative effects on operator performance corresponding to controlled experiments in a less realistic task environment. Tools proposed to keep the operator at an optimum task load are (adaptive) task allocation and interface support.

  1. 15-month-olds' transfer of learning between touch screen and real-world displays: language cues and cognitive loads.

    PubMed

    Zack, Elizabeth; Gerhardstein, Peter; Meltzoff, Andrew N; Barr, Rachel

    2013-02-01

    Infants have difficulty transferring information between 2D and 3D sources. The current study extends Zack, Barr, Gerhardstein, Dickerson & Meltzoff's (2009) touch screen imitation task to examine whether the addition of specific language cues significantly facilitates 15-month-olds' transfer of learning between touch screens and real-world 3D objects. The addition of two kinds of linguistic cues (object label plus verb or nonsense name) did not elevate action imitation significantly above levels observed when such language cues were not used. Language cues hindered infants' performance in the 3D→2D direction of transfer, but only for the object label plus verb condition. The lack of a facilitative effect of language is discussed in terms of competing cognitive loads imposed by conjointly transferring information across dimensions and processing linguistic cues in an action imitation task at this age.

  2. Dehydrogenation Properties of Magnesium Hydride Loaded with Fe, Fe-C, and Fe-Mg Additives.

    PubMed

    Pukazhselvan, D; Nasani, Narendar; Yang, Tao; Bdikin, Igor; Kovalevsky, Andrei V; Fagg, Duncan P

    2017-02-02

    This study highlights that Fe additives offer better catalytic properties than carbon, Fe-C (iron carbide/carbon composites), and Fe-Mg (Mg2 FeH6 ) additives for the low-temperature dehydrogenation of magnesium hydride. The in situ X-ray diffraction measurements prove the formation of a Mg2 FeH6 phase in iron additive loaded MgH2 . Nonetheless, differential scanning calorimetry data suggest that this Mg2 FeH6 phase does not have any influence on dehydrogenation properties of MgH2 . On the other hand, the composite system Mg2 FeH6 /MgH2 shows significantly improved dehydrogenation properties even in absence of further additives. It is suggested that the improved system performance of Fe loaded MgH2 is attributed to restrictions on crystal growth of MgH2 and the catalytic behavior of Fe nanoparticles, rather than any intrinsic catalytic properties offered by the formed mixed metal phase Mg2 FeH6 .

  3. The Effects of Social Cue Principles on Cognitive Load, Situational Interest, Motivation, and Achievement in Pedagogical Agent Multimedia Learning

    ERIC Educational Resources Information Center

    Park, Sanghoon

    2015-01-01

    Animated pedagogical agents have become popular in multimedia learning with combined delivery of verbal and non-verbal forms of information. In order to reduce unnecessary cognitive load caused by such multiple forms of information and also to foster generative cognitive processing, multimedia design principles with social cues are suggested…

  4. Reading Subtitles and Taking Enotes While Learning Scientific Materials in a Multimedia Environment: Cognitive Load Perspectives on EFL Students

    ERIC Educational Resources Information Center

    Lin, John J. H.; Lee, Yuan-Husan; Wang, Dai-Yi; Lin, Sunny S. J.

    2016-01-01

    The present study investigated the effects of providing subtitles and taking enotes on cognitive load and performance. A total of 73 English-as-a-Foreign-Language (EFL) undergraduates learned brain anatomy and cognitive functions through multimedia programs. We used a 2 (subtitle/no) x 2 (taking enotes/no) factorial design to test the following:…

  5. The Spatial Release of Cognitive Load in Cocktail Party Is Determined by the Relative Levels of the Talkers.

    PubMed

    Andéol, Guillaume; Suied, Clara; Scannella, Sébastien; Dehais, Frédéric

    2017-01-18

    In a multi-talker situation, spatial separation between talkers reduces cognitive processing load: this is the "spatial release of cognitive load". The present study investigated the role played by the relative levels of the talkers on this spatial release of cognitive load. During the experiment, participants had to report the speech emitted by a target talker in the presence of a concurrent masker talker. The spatial separation (0° and 120° angular distance in azimuth) and the relative levels of the talkers (adverse, intermediate, and favorable target-to-masker ratio) were manipulated. The cognitive load was assessed with a prefrontal functional near-infrared spectroscopy. Data from 14 young normal-hearing listeners revealed that the target-to-masker ratio had a direct impact on the spatial release of cognitive load. Spatial separation significantly reduced the prefrontal activity only for the intermediate target-to-masker ratio and had no effect on prefrontal activity for the favorable and the adverse target-to-masker ratios. Therefore, the relative levels of the talkers might be a key point to determine the spatial release of cognitive load and more specifically the prefrontal activity induced by spatial cues in multi-talker situations.

  6. Taking the easy way out? Increasing implementation effort reduces probability maximizing under cognitive load.

    PubMed

    Schulze, Christin; Newell, Ben R

    2016-07-01

    Cognitive load has previously been found to have a positive effect on strategy selection in repeated risky choice. Specifically, whereas inferior probability matching often prevails under single-task conditions, optimal probability maximizing sometimes dominates when a concurrent task competes for cognitive resources. We examined the extent to which this seemingly beneficial effect of increased task demands hinges on the effort required to implement each of the choice strategies. Probability maximizing typically involves a simple repeated response to a single option, whereas probability matching requires choice proportions to be tracked carefully throughout a sequential choice task. Here, we flipped this pattern by introducing a manipulation that made the implementation of maximizing more taxing and, at the same time, allowed decision makers to probability match via a simple repeated response to a single option. The results from two experiments showed that increasing the implementation effort of probability maximizing resulted in decreased adoption rates of this strategy. This was the case both when decision makers simultaneously learned about the outcome probabilities and responded to a dual task (Exp. 1) and when these two aspects were procedurally separated in two distinct stages (Exp. 2). We conclude that the effort involved in implementing a choice strategy is a key factor in shaping repeated choice under uncertainty. Moreover, highlighting the importance of implementation effort casts new light on the sometimes surprising and inconsistent effects of cognitive load that have previously been reported in the literature.

  7. Deception and Cognitive Load: Expanding Our Horizon with a Working Memory Model

    PubMed Central

    Sporer, Siegfried L.

    2016-01-01

    Recently, studies on deception and its detection have increased dramatically. Many of these studies rely on the “cognitive load approach” as the sole explanatory principle to understand deception. These studies have been exclusively on lies about negative actions (usually lies of suspects of [mock] crimes). Instead, we need to re-focus more generally on the cognitive processes involved in generating both lies and truths, not just on manipulations of cognitive load. Using Baddeley’s (2000, 2007, 2012) working memory model, which integrates verbal and visual processes in working memory with retrieval from long-term memory and control of action, not only verbal content cues but also nonverbal, paraverbal, and linguistic cues can be investigated within a single framework. The proposed model considers long-term semantic, episodic and autobiographical memory and their connections with working memory and action. It also incorporates ironic processes of mental control (Wegner, 1994, 2009), the role of scripts and schemata and retrieval cues and retrieval processes. Specific predictions of the model are outlined and support from selective studies is presented. The model is applicable to different types of reports, particularly about lies and truths about complex events, and to different modes of production (oral, hand-written, typed). Predictions regarding several moderator variables and methods to investigate them are proposed. PMID:27092090

  8. EEG-based cognitive load of processing events in 3D virtual worlds is lower than processing events in 2D displays.

    PubMed

    Dan, Alex; Reiner, Miriam

    2016-08-31

    Interacting with 2D displays, such as computer screens, smartphones, and TV, is currently a part of our daily routine; however, our visual system is built for processing 3D worlds. We examined the cognitive load associated with a simple and a complex task of learning paper-folding (origami) by observing 2D or stereoscopic 3D displays. While connected to an electroencephalogram (EEG) system, participants watched a 2D video of an instructor demonstrating the paper-folding tasks, followed by a stereoscopic 3D projection of the same instructor (a digital avatar) illustrating identical tasks. We recorded the power of alpha and theta oscillations and calculated the cognitive load index (CLI) as the ratio of the average power of frontal theta (Fz.) and parietal alpha (Pz). The results showed a significantly higher cognitive load index associated with processing the 2D projection as compared to the 3D projection; additionally, changes in the average theta Fz power were larger for the 2D conditions as compared to the 3D conditions, while alpha average Pz power values were similar for 2D and 3D conditions for the less complex task and higher in the 3D state for the more complex task. The cognitive load index was lower for the easier task and higher for the more complex task in 2D and 3D. In addition, participants with lower spatial abilities benefited more from the 3D compared to the 2D display. These findings have implications for understanding cognitive processing associated with 2D and 3D worlds and for employing stereoscopic 3D technology over 2D displays in designing emerging virtual and augmented reality applications.

  9. When Breathing Interferes with Cognition: Experimental Inspiratory Loading Alters Timed Up-and-Go Test in Normal Humans.

    PubMed

    Nierat, Marie-Cécile; Demiri, Suela; Dupuis-Lozeron, Elise; Allali, Gilles; Morélot-Panzini, Capucine; Similowski, Thomas; Adler, Dan

    2016-01-01

    Human breathing stems from automatic brainstem neural processes. It can also be operated by cortico-subcortical networks, especially when breathing becomes uncomfortable because of external or internal inspiratory loads. How the "irruption of breathing into consciousness" interacts with cognition remains unclear, but a case report in a patient with defective automatic breathing (Ondine's curse syndrome) has shown that there was a cognitive cost of breathing when the respiratory cortical networks were engaged. In a pilot study of putative breathing-cognition interactions, the present study relied on a randomized design to test the hypothesis that experimentally loaded breathing in 28 young healthy subjects would have a negative impact on cognition as tested by "timed up-and-go" test (TUG) and its imagery version (iTUG). Progressive inspiratory threshold loading resulted in slower TUG and iTUG performance. Participants consistently imagined themselves faster than they actually were. However, progressive inspiratory loading slowed iTUG more than TUG, a finding that is unexpected with regard to the known effects of dual tasking on TUG and iTUG (slower TUG but stable iTUG). Insofar as the cortical networks engaged in response to inspiratory loading are also activated during complex locomotor tasks requiring cognitive inputs, we infer that competition for cortical resources may account for the breathing-cognition interference that is evidenced here.

  10. Additive genetic breeding values correlate with the load of partially deleterious mutations.

    PubMed

    Tomkins, Joseph L; Penrose, Marissa A; Greeff, Johan; LeBas, Natasha R

    2010-05-14

    The mutation-selection-balance model predicts most additive genetic variation to arise from numerous mildly deleterious mutations of small effect. Correspondingly, "good genes" models of sexual selection and recent models for the evolution of sex are built on the assumption that mutational loads and breeding values for fitness-related traits are correlated. In support of this concept, inbreeding depression was negatively genetically correlated with breeding values for traits under natural and sexual selection in the weevil Callosobruchus maculatus. The correlations were stronger in males and strongest for condition. These results confirm the role of existing, partially recessive mutations in maintaining additive genetic variation in outbred populations, reveal the nature of good genes under sexual selection, and show how sexual selection can offset the cost of sex.

  11. An investigation of pupil-based cognitive load measurement with low cost infrared webcam under light reflex interference.

    PubMed

    Chen, Siyuan; Epps, Julien; Chen, Fang

    2013-01-01

    Using the task-evoked pupillary response (TEPR) to index cognitive load can contribute significantly to the assessment of memory function and cognitive skills in patients. However, the measurement of pupillary response is currently limited to a well-controlled lab environment due to light reflex and also relies heavily on expensive video-based eye trackers. Furthermore, commercial eye trackers are usually dedicated to gaze direction measurement, and their calibration procedure and computing resource are largely redundant for pupil-based cognitive load measurement (PCLM). In this study, we investigate the validity of cognitive load measurement with (i) pupil light reflex in a less controlled luminance background; (ii) a low-cost infrared (IR) webcam for the TEPR in a controlled luminance background. ANOVA results show that with an appropriate baseline selection and subtraction, the light reflex is significantly reduced, suggesting the possibility of less constrained practical applications of PCLM. Compared with the TEPR from a commercial remote eye tracker, a low-cost IR webcam achieved a similar TEPR pattern and no significant difference was found between the two devices in terms of cognitive load measurement across five induced load levels.

  12. Gait profile score and movement analysis profile in patients with Parkinson's disease during concurrent cognitive load

    PubMed Central

    Speciali, Danielli S.; Oliveira, Elaine M.; Cardoso, Jefferson R.; Correa, João C. F.; Baker, Richard; Lucareli, Paulo R. G.

    2014-01-01

    Background: Gait disorders are common in individuals with Parkinson's Disease (PD) and the concurrent performance of motor and cognitive tasks can have marked effects on gait. The Gait Profile Score (GPS) and the Movement Analysis Profile (MAP) were developed in order to summarize the data of kinematics and facilitate understanding of the results of gait analysis. Objective: To investigate the effectiveness of the GPS and MAP in the quantification of changes in gait during a concurrent cognitive load while walking in adults with and without PD. Method: Fourteen patients with idiopathic PD and nine healthy subjects participated in the study. All subjects performed single and dual walking tasks. The GPS/MAP was computed from three-dimensional gait analysis data. Results: Differences were found between tasks for GPS (P<0.05) and Gait Variable Score (GVS) (pelvic rotation, knee flexion-extension and ankle dorsiflexion-plantarflexion) (P<0.05) in the PD group. An interaction between task and group was observed for GPS (P<0.01) for the right side (Cohen's ¯d=0.99), left side (Cohen's ¯d=0.91), and overall (Cohen's ¯d=0.88). No interaction was observed only for hip internal-external rotation and foot internal-external progression GVS variables in the PD group. Conclusions: The results showed gait impairment during the dual task and suggest that GPS/MAP may be used to evaluate the effects of concurrent cognitive load while walking in patients with PD. PMID:25054382

  13. Load-dependent Optimization of Honeycombs for Sandwich Components - New Possibilities by Using Additive Layer Manufacturing

    NASA Astrophysics Data System (ADS)

    Riss, Fabian; Schilp, Johannes; Reinhart, Gunther

    Due to their feasible geometric complexity, additive layer manufacturing (ALM) processes show a highpotential for the production of lightweight components.Therefore, ALM processes enable the realization of bionic-designedcomponents like honeycombs, which are optimized depending upon load and outer boundary conditions.This optimization is based on a closed-loop, three-steps methodology: At first, each honeycomb is conformed to the surface of the part. Secondly, the structure is optimizedfor lightweight design.It is possible to achieve a homogeneous stress distribution in the part by varying the wall thickness, honeycombdiameter and the amount of honeycombs, depending on the subjected stresses and strains. At last, the functional components like threads or bearing carriers are integrated directly into the honeycomb core.Using all these steps as an iterative process, it is possible to reduce the mass of sandwich components about 50 percent compared to conventional approaches.

  14. Teaching Gene Technology in an Outreach Lab: Students' Assigned Cognitive Load Clusters and the Clusters' Relationships to Learner Characteristics, Laboratory Variables, and Cognitive Achievement

    ERIC Educational Resources Information Center

    Scharfenberg, Franz-Josef; Bogner, Franz X.

    2013-01-01

    This study classified students into different cognitive load (CL) groups by means of cluster analysis based on their experienced CL in a gene technology outreach lab which has instructionally been designed with regard to CL theory. The relationships of the identified student CL clusters to learner characteristics, laboratory variables, and…

  15. The impact of clickers instruction on cognitive loads and listening and speaking skills in college English class.

    PubMed

    Yu, Zhonggen; Chen, Wentao; Kong, Yong; Sun, Xiao Ling; Zheng, Jing

    2014-01-01

    Clickers might own a bright future in China if properly introduced although they have not been widely acknowledged as an effective tool to facilitate English learning and teaching in Chinese contexts. By randomly selecting participants from undergraduates in a university in China over four academic years, this study aims to identify the impact of clickers on college English listening and speaking skills, and differences in cognitive loads between clickers and traditional multimedia assisted instruction modes. It was concluded that in China's college English class, compared with multimedia assisted instruction, (1) clickers could improve college English listening skills; (2) clickers could improve college English speaking skills; and (3) clickers could reduce undergraduates' cognitive loads in College English Class. Reasons for the results and defects in this study were also explored and discussed, based on learning, teaching and cognitive load theories. Some Suggestions for future research were also raised.

  16. Determine Minimum Silver Flake Addition to GCM for Iodine Loaded AgZ

    SciTech Connect

    Garino, Terry J.; Nenoff, Tina M.; Rodriguez, Mark A.

    2014-04-01

    The minimum amount of silver flake required to prevent loss of I{sub 2} during sintering in air for a SNL Glass Composite Material (GCM) Waste Form containing AgI-MOR (ORNL, 8.7 wt%) was determined to be 1.1 wt% Ag. The final GCM composition prior to sintering was 20 wt% AgI-MOR, 1.1 wt% Ag, and 80 wt% Bi-Si oxide glass. The amount of silver flake needed to suppress iodine loss was determined using thermo gravimetric analysis with mass spectroscopic off-gas analysis. These studies found that the ratio of silver to AgI-MOR required is lower in the presence of the glass than without it. Therefore an additional benefit of the GCM is that it serves to inhibit some iodine loss during processing. Alternatively, heating the AgI-MOR in inert atmosphere instead of air allowed for densified GCM formation without I{sub 2} loss, and no necessity for the addition of Ag. The cause of this behavior is found to be related to the oxidation of the metallic Ag to Ag{sup +} when heated to above ~300{degrees}C in air. Heating rate, iodine loading levels and atmosphere are the important variables that determine AgI migration and results suggest that AgI may be completely incorporated into the mordenite structure by the 550{degrees}C sintering temperature.

  17. Linear QoS goals of additive and concave metrics in ad hoc cognitive packet routing.

    PubMed

    Lent, Ricardo

    2006-12-01

    This paper addresses two scalability problems related to the cognitive map of packets in ad hoc cognitive packet networks and proposes a solution. Previous works have included latency as part of the routing goal of smart packets, which requires packets to collect their arrival time at each node in a path. Such a requirement resulted in a packet overhead proportional to the path length. The second problem is that the multiplicative form of path availability, which was employed to measure resources, loses accuracy in long paths. To solve these problems, new goals are proposed in this paper. These goals are linear functions of low-overhead metrics and can provide similar performance results with lower cost. One direct result shown in simulation is that smart packets driven by a linear function of path length and buffer occupancy can effectively balance the traffic of multiple flows without the large overhead that would be needed if round-trip delay was used. In addition, energy-aware routing is also studied under this scheme as well as link selection based on their expected level of security.

  18. Changes in running pattern due to fatigue and cognitive load in orienteering.

    PubMed

    Millet, Guillaume Y; Divert, Caroline; Banizette, Marion; Morin, Jean-Benoit

    2010-01-01

    The aim of this study was to examine the influence of fatigue on running biomechanics in normal running, in normal running with a cognitive task, and in running while map reading. Nineteen international and less experienced orienteers performed a fatiguing running exercise of duration and intensity similar to a classic distance orienteering race on an instrumented treadmill while performing mental arithmetic, an orienteering simulation, and control running at regular intervals. Two-way repeated-measures analysis of variance did not reveal any significant difference between mental arithmetic and control running for any of the kinematic and kinetic parameters analysed eight times over the fatiguing protocol. However, these parameters were systematically different between the orienteering simulation and the other two conditions (mental arithmetic and control running). The adaptations in orienteering simulation running were significantly more pronounced in the elite group when step frequency, peak vertical ground reaction force, vertical stiffness, and maximal downward displacement of the centre of mass during contact were considered. The effects of fatigue on running biomechanics depended on whether the orienteers read their map or ran normally. It is concluded that adding a cognitive load does not modify running patterns. Therefore, all changes in running pattern observed during the orienteering simulation, particularly in elite orienteers, are the result of adaptations to enable efficient map reading and/or potentially prevent injuries. Finally, running patterns are not affected to the same extent by fatigue when a map reading task is added.

  19. How Do the Cognitive Load, Self-Efficacy and Attitude of Pre-Service Teachers Shift in the Multimedia Science Learning Process?

    ERIC Educational Resources Information Center

    Efendioglu, Akin

    2016-01-01

    The aim of this study is to investigate pre-service teacher's cognitive load types (intrinsic load-IL, extraneous load-EL, and germane load-GL), academic achievements, and affective characteristics (attitude and self-efficacy) at two stages of experimental learning processes. The first and the second groups used explanatory instructional…

  20. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  1. Nutrient additions in pristine Patagonian Sphagnum bog vegetation: can phosphorus addition alleviate (the effects of) increased nitrogen loads.

    PubMed

    Fritz, C; van Dijk, G; Smolders, A J P; Pancotto, V A; Elzenga, T J T M; Roelofs, J G M; Grootjans, A P

    2012-05-01

    Sphagnum-bog ecosystems have a limited capability to retain carbon and nutrients when subjected to increased nitrogen (N) deposition. Although it has been proposed that phosphorus (P) can dilute negative effects of nitrogen by increasing biomass production of Sphagnum mosses, it is still unclear whether P-addition can alleviate physiological N-stress in Sphagnum plants. A 3-year fertilisation experiment was conducted in lawns of a pristine Sphagnum magellanicum bog in Patagonia, where competing vascular plants were practically absent. Background wet deposition of nitrogen was low (≈ 0.1-0.2 g · N · m(-2) · year(-1)). Nitrogen (4 g · N · m(-2) · year(-1)) and phosphorus (1 g · P · m(-2) · year(-1)) were applied, separately and in combination, six times during the growing season. P-addition substantially increased biomass production of Sphagnum. Nitrogen and phosphorus changed the morphology of Sphagnum mosses by enhancing height increment, but lowering moss stem density. In contrast to expectations, phosphorus failed to alleviate physiological stress imposed by excess nitrogen (e.g. amino acid accumulation, N-saturation and decline in photosynthetic rates). We conclude that despite improving growth conditions by P-addition, Sphagnum-bog ecosystems remain highly susceptible to nitrogen additions. Increased susceptibility to desiccation by nutrients may even worsen the negative effects of excess nitrogen especially in windy climates like in Patagonia.

  2. Addition of cholesterol-loaded cyclodextrins to the thawing extender: effects on boar sperm quality.

    PubMed

    Tomás, C; Gómez-Fernández, J; Gómez-Izquierdo, E; Mocé, E; de Mercado, E

    2014-06-01

    The aim of the present study was to evaluate the effect that the addition of cholesterol-loaded cyclodextrins (CLC) to the thawing extender has on the quality of frozen-thawed boar sperm. Pooled semen (n = 5) from three boars was used for the experiments. The semen was cryopreserved with an egg-yolk-based extender, it was diluted after thawing in Beltsville thawing solution (BTS) supplemented with different concentrations of CLC (0, 12.5, 25, 50 or 100 mg/500 × 10(6) sperm), and these samples were incubated at 37°C for 150 min. The following parameters of sperm quality were evaluated 30 and 150 min after incubation: sperm with intact plasma membrane (SIPM; %), sperm with normal acrosomal ridge (NAR; %), total motile sperm (TMS; %), progressively motile sperm (PMS; %) and kinetic parameters. Both SIPM and NAR increased (p < 0.05) when the thawing extender was supplemented with 12.5, 25 and 50 mg CLC/500 × 10(6) sperm. Nevertheless, motility decreased (p < 0.05) when the concentration of CLC exceeded 12.5 mg CLC/500 × 10(6) sperm. In conclusion, our results suggest that the supplementation of thawing extenders with CLC improves sperm viability and reduces acrosome damage after freezing/thawing.

  3. Long-term effects of provided low and high glycemic load low energy diets on mood and cognition.

    PubMed

    Cheatham, Rachel A; Roberts, Susan B; Das, Sai Krupa; Gilhooly, Cheryl H; Golden, Julie K; Hyatt, Raymond; Lerner, Debra; Saltzman, Edward; Lieberman, Harris R

    2009-09-07

    Energy-restricted low glycemic load diets are being used increasingly for weight loss. However, the long-term effects of such regimens on mood and cognitive performance are not known. We assessed the effects of low glycemic load (LG) and high glycemic load (HG) energy-restricted diets on mood and cognitive performance during 6 months of a randomized controlled trial when all food was provided. Subjects were 42 healthy overweight adults (age 35+/-5 years; BMI 27.8+/-1.6 kg/m(2)) with a mean weight loss of 8.7+/-5.0% that did not differ significantly by diet randomization. Mood was assessed by using the Profile of Mood States (POMS) questionnaire. Cognitive performance was assessed by using computerized tests of simple reaction time, vigilance, learning, short-term memory and attention, and language-based logical reasoning. Worsening mood outcome over time was observed in the HG diet group compared to the LG for the depression subscale of POMS (p=0.009 after including hunger as a covariate). There was no significant change over time in any cognitive performance values. These findings suggest a negative effect of an HG weight loss diet on sub-clinical depression but, in contrast to a previous suggestion, provide no support for differential effects of LG versus HD diets on cognitive performance.

  4. Low cognitive load and reduced arousal impede practice effects on executive functioning, metacognitive confidence and decision making.

    PubMed

    Jackson, Simon A; Kleitman, Sabina; Aidman, Eugene

    2014-01-01

    The present study investigated the effects of low cognitive workload and the absence of arousal induced via external physical stimulation (motion) on practice-related improvements in executive (inhibitory) control, short-term memory, metacognitive monitoring and decision making. A total of 70 office workers performed low and moderately engaging passenger tasks in two successive 20-minute simulated drives and repeated a battery of decision making and inhibitory control tests three times—before, between and after these drives. For half the participants, visual simulation was synchronised with (moderately arousing) motion generated through LAnd Motion Platform, with vibration levels corresponding to a well-maintained unsealed road. The other half performed the same simulated drive without motion. Participants' performance significantly improved over the three test blocks, which is indicative of typical practice effects. The magnitude of these improvements was the highest when both motion and moderate cognitive load were present. The same effects declined either in the absence of motion (low arousal) or following a low cognitive workload task, thus suggesting two distinct pathways through which practice-related improvements in cognitive performance may be hampered. Practice, however, degraded certain aspects of metacognitive performance, as participants became less likely to detect incorrect decisions in the decision-making test with each subsequent test block. Implications include consideration of low cognitive load and arousal as factors responsible for performance decline and targets for the development of interventions/strategies in low load/arousal conditions such as autonomous vehicle operations and highway driving.

  5. The Effects of Time-Compressed Instruction and Redundancy on Learning and Learners' Perceptions of Cognitive Load

    ERIC Educational Resources Information Center

    Pastore, Ray

    2012-01-01

    Can increasing the speed of audio narration in multimedia instruction decrease training time and still maintain learning? The purpose of this study was to examine the effects of time-compressed instruction and redundancy on learning and learners' perceptions of cognitive load. 154 university students were placed into conditions that consisted of…

  6. Improving Learning Results and Reducing Cognitive Load through 3D Courseware on Color Management and Inspection Instruction

    ERIC Educational Resources Information Center

    Hsiung, Liang-Yuan; Lai, Mu-Hui

    2013-01-01

    This study intends to solve the problem that schools in Taiwan lack of the equipment for color management and inspection instruction and seek ways to improve learning results and reduce cognitive load. The researchers developed 3D courseware for color management and inspection through a research and development process. To further scrutinize the…

  7. The Instructional Effects of Diagrams and Time-Compressed Instruction on Student Achievement and Learners' Perceptions of Cognitive Load

    ERIC Educational Resources Information Center

    Pastore, Raymond S.

    2009-01-01

    The purpose of this study was to examine the effects of visual representations and time-compressed instruction on learning and learners' perceptions of cognitive load. Time-compressed instruction refers to instruction that has been increased in speed without sacrificing quality. It was anticipated that learners would be able to gain a conceptual…

  8. The Scientific Value of Cognitive Load Theory: A Research Agenda Based on the Structuralist View of Theories

    ERIC Educational Resources Information Center

    Gerjets, Peter; Scheiter, Katharina; Cierniak, Gabriele

    2009-01-01

    In this paper, two methodological perspectives are used to elaborate on the value of cognitive load theory (CLT) as a scientific theory. According to the more traditional critical rationalism of Karl Popper, CLT cannot be considered a scientific theory because some of its fundamental assumptions cannot be tested empirically and are thus not…

  9. Features of Representations in General Chemistry Textbooks: A Peek through the Lens of the Cognitive Load Theory

    ERIC Educational Resources Information Center

    Nyachwaya, James M.; Gillaspie, Merry

    2016-01-01

    The goals of this study were (1) determine the prevalence of various features of representations in five general chemistry textbooks used in the United States, and (2) use cognitive load theory to draw implications of the various features of analyzed representations. We adapted the Graphical Analysis Protocol (GAP) (Slough et al., 2010) to look at…

  10. Reading English as a Second Language with Vocabulary Definitions: Cognitive Load Effects on Comprehension and Vocabulary Learning.

    ERIC Educational Resources Information Center

    Yeung, Alexander Seeshing

    Two experiments were conducted to examine the effects of cognitive load management using vocabulary definitions in reading passages for readers of English as a second language (ESL) with different levels of expertise who were attending school in Hong Kong. Experiment 1 found that vocabulary definitions integrated within a passage (integrated…

  11. A Cognitive Load Reduction Approach to Exploratory Learning and Its Application to an Interactive Simulation-based Learning System.

    ERIC Educational Resources Information Center

    Kashihara, Akihiro; Kinshuk; Oppermann, Reinhard; Rashev, Rossen; Simm, Helmut

    2000-01-01

    Describes a methodology for supporting exploratory learning that attempts to limit learning space, called exploration space, and adequately control the cognitive load learners would face in their exploration process. In Exploration Space Control (ESC) the extent of exploration space is controlled according to domain complexity, but also to…

  12. Do English Listening Outcome and Cognitive Load Change for Different Media Delivery Modes in U-Learning?

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng; Lei, Hao; Tseng, Ju-Shih

    2014-01-01

    Although ubiquitous learning enhances students' access to learning materials, it is crucial to find out which media delivery modes produce the best results for English listening comprehension. The present study examined the effect of media delivery mode (sound and text vs. sound) on English listening comprehension and cognitive load. Participants…

  13. Media Presentation Mode, English Listening Comprehension and Cognitive Load in Ubiquitous Learning Environments: Modality Effect or Redundancy Effect?

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng; Lei, Hao; Tseng, Ju-Shih

    2011-01-01

    Although ubiquitous learning enhances students' access to learning materials, it is crucial to find out which media presentation modes produce the best results for English listening comprehension. The present study examined the effect of media presentation mode (sound and text versus sound) on English listening comprehension and cognitive load.…

  14. Cooperative Weblog Learning in Higher Education: Its Facilitating Effects on Social Interaction, Time Lag, and Cognitive Load

    ERIC Educational Resources Information Center

    Huang, Tien-Chi; Huang, Yueh-Min; Yu, Fu-Yun

    2011-01-01

    This paper examines the effects of using weblog technologies to support cooperative learning in higher education. The study focused on the effects of features embedded in weblogs on social interactions, time lags, and cognitive loads. A quasi-experimental control-group research design was adopted. The participants were 115 undergraduates who were…

  15. On the Flexibility of Grammatical Advance Planning during Sentence Production: Effects of Cognitive Load on Multiple Lexical Access

    ERIC Educational Resources Information Center

    Wagner, Valentin; Jescheniak, Jorg D.; Schriefers, Herbert

    2010-01-01

    Three picture-word interference experiments addressed the question of whether the scope of grammatical advance planning in sentence production corresponds to some fixed unit or rather is flexible. Subjects produced sentences of different formats under varying amounts of cognitive load. When speakers described 2-object displays with simple…

  16. Do Learner Characteristics Moderate the Seductive-Details-Effect? A Cognitive-Load-Study Using Eye-Tracking

    ERIC Educational Resources Information Center

    Park, Babette; Korbach, Andreas; Brünken, Roland

    2015-01-01

    The present study examines whether the seductive-details effect is moderated by spatial ability and prior knowledge, which are two of the most relevant learner characteristics in multimedia learning. It is assumed that the seductive-details effect with an increase in extraneous cognitive load and a decrease in perceptual processing and learning…

  17. Lifestyle, glucose regulation and the cognitive effects of glucose load in middle-aged adults.

    PubMed

    Riby, Leigh M; McLaughlin, Jennifer; Riby, Deborah M; Graham, Cheryl

    2008-11-01

    Interventions aimed at improving glucose regulatory mechanisms have been suggested as a possible source of cognitive enhancement in the elderly. In particular, previous research has identified episodic memory as a target for facilitation after either moderate increases in glycaemia (after a glucose drink) or after improvements in glucose regulation. The present study aimed to extend this research by examining the joint effects of glucose ingestion and glucose regulation on cognition. In addition, risk factors associated with the development of poor glucose regulation in middle-aged adults were considered. In a repeated measures design, thirty-three middle-aged adults (aged 35-55 years) performed a battery of memory and non-memory tasks after either 25 g or 50 g glucose or a sweetness matched placebo drink. To assess the impact of individual differences in glucose regulation, blood glucose measurements were taken on four occasions during testing. A lifestyle and diet questionnaire was also administered. Consistent with previous research, episodic memory ability benefited from glucose ingestion when task demands were high. Blood glucose concentration was also found to predict performance across a number of cognitive domains. Interestingly, the risk factors associated with poor glucose regulation were linked to dietary impacts traditionally associated with poor health, e.g. the consumption of high-sugar sweets and drinks. The research replicates earlier work suggesting that task demands are critical to the glucose facilitation effect. Importantly, the data demonstrate clear associations between elevated glycaemia and relatively poor cognitive performance, which may be partly due to the effect of dietary and lifestyle factors.

  18. Perceptual load in sport and the heuristic value of the perceptual load paradigm in examining expertise-related perceptual-cognitive adaptations.

    PubMed

    Furley, Philip; Memmert, Daniel; Schmid, Simone

    2013-03-01

    In two experiments, we transferred perceptual load theory to the dynamic field of team sports and tested the predictions derived from the theory using a novel task and stimuli. We tested a group of college students (N = 33) and a group of expert team sport players (N = 32) on a general perceptual load task and a complex, soccer-specific perceptual load task in order to extend the understanding of the applicability of perceptual load theory and further investigate whether distractor interference may differ between the groups, as the sport-specific processing task may not exhaust the processing capacity of the expert participants. In both, the general and the specific task, the pattern of results supported perceptual load theory and demonstrates that the predictions of the theory also transfer to more complex, unstructured situations. Further, perceptual load was the only determinant of distractor processing, as we neither found expertise effects in the general perceptual load task nor the sport-specific task. We discuss the heuristic utility of using response-competition paradigms for studying both general and domain-specific perceptual-cognitive adaptations.

  19. Online Reading: A Preliminary Study of the Impact of Integrated and Split-Attention Formats on L2 Students' Cognitive Load

    ERIC Educational Resources Information Center

    Al-Shehri, Saleh; Gitsaki, Christina

    2010-01-01

    Cognitive load theory has been utilized by second language acquisition (SLA) researchers to account for differences in learner performance with regards to different learning tasks. Certain instructional designs were shown to have an impact on cognitive load and working memory, and this impact was found to be accentuated in a multimedia environment…

  20. Measuring Cognitive Load with Electroencephalography and Self-Report: Focus on the Effect of English-Medium Learning for Korean Students

    ERIC Educational Resources Information Center

    Lee, Hyunjeong

    2014-01-01

    This study investigated a reliable and valid method for measuring cognitive load during learning through comparing various types of cognitive load measurements: electroencephalography (EEG), self-reporting, and learning outcome. A total of 43 college-level students underwent watching a documentary delivered in English or in Korean. EEG was…

  1. Cognitive Load Imposed by Knobology May Adversely Affect Learners' Perception of Utility in Using Ultrasonography to Learn Physical Examination Skills, but Not Anatomy

    ERIC Educational Resources Information Center

    Jamniczky, Heather A.; McLaughlin, Kevin; Kaminska, Malgorzata E.; Raman, Maitreyi; Somayaji, Ranjani; Wright, Bruce; Ma, Irene W. Y.

    2015-01-01

    Ultrasonography is increasingly used for teaching anatomy and physical examination skills but its effect on cognitive load is unknown. This study aimed to determine ultrasound's perceived utility for learning, and to investigate the effect of cognitive load on its perceived utility. Consenting first-year medical students (n?=?137) completed…

  2. Cognitive load reduces visual identity negative priming by disabling the retrieval of task-inappropriate prime information: an ERP study.

    PubMed

    Gibbons, Henning; Stahl, Jutta

    2010-05-12

    The present event-related potentials (ERP) study investigated the mechanisms by which cognitive load reduces the negative priming (NP) effect in a letter flanker task. On each trial, participants (N=20) first encoded a set of one to five digits, then responded to two successive flanker displays (prime, probe), and finally recalled a certain digit from the set. The flanker NP effect (i.e., increased probe RT when the prime distractor repeated as the probe target) was significant under low (1-2 items) but not high cognitive load (4-5 items). NP in the low-load condition was accompanied by left-anterior P2/N2 amplitude modulation which was also observed for prime-probe target repetitions and hence may reflect the processing of prime-probe similarity. Under high load, the P2/N2 effect was absent. It is suggested that cognitive load interferes with a retrieval-based mechanism in NP. Findings support episodic-retrieval explanations of visual identity-based NP.

  3. The Effects of Split-Attention and Redundancy on Cognitive Load When Learning Cognitive and Psychomotor Tasks

    ERIC Educational Resources Information Center

    Pociask, Fredrick D.; Morrison, Gary

    2004-01-01

    Human working memory can be defined as a component system responsible for the temporary storage and manipulation of information related to higher level cognitive behaviors, such as understanding and reasoning (Baddeley, 1992; Becker & Morris, 1999). Working memory, while able to manage a complex array of cognitive activities, presents with an…

  4. Are delta-aminolevulinate dehydratase inhibition and metal concentrations additional factors for the age-related cognitive decline?

    PubMed

    Baierle, Marília; Charão, Mariele F; Göethel, Gabriela; Barth, Anelise; Fracasso, Rafael; Bubols, Guilherme; Sauer, Elisa; Campanharo, Sarah C; Rocha, Rafael C C; Saint'Pierre, Tatiana D; Bordignon, Suelen; Zibetti, Murilo; Trentini, Clarissa M; Avila, Daiana S; Gioda, Adriana; Garcia, Solange C

    2014-10-17

    Aging is often accompanied by cognitive impairments and influenced by oxidative status and chemical imbalances. Thus, this study was conducted to examine whether age-related cognitive deficit is associated with oxidative damage, especially with inhibition of the enzyme delta-aminolevulinate dehydratase (ALA-D), as well as to verify the influence of some metals in the enzyme activity and cognitive performance. Blood ALA-D activity, essential (Fe, Zn, Cu, Se) and non-essential metals (Pb, Cd, Hg, As, Cr, Ni, V) were measured in 50 elderly and 20 healthy young subjects. Cognitive function was assessed by tests from Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery and other. The elderly group presented decreased ALA-D activity compared to the young group. The index of ALA-D reactivation was similar to both study groups, but negatively associated with metals. The mean levels of essential metals were within the reference values, while the most toxic metals were above them in both groups. Cognitive function impairments were observed in elderly group and were associated with decreased ALA-D activity, with lower levels of Se and higher levels of toxic metals (Hg and V). Results suggest that the reduced ALA-D activity in elderly can be an additional factor involved in cognitive decline, since its inhibition throughout life could lead to accumulation of the neurotoxic compound ALA. Toxic metals were found to contribute to cognitive decline and also to influence ALA-D reactivation.

  5. Are Delta-Aminolevulinate Dehydratase Inhibition and Metal Concentrations Additional Factors for the Age-Related Cognitive Decline?

    PubMed Central

    Baierle, Marília; Charão, Mariele F.; Göethel, Gabriela; Barth, Anelise; Fracasso, Rafael; Bubols, Guilherme; Sauer, Elisa; Campanharo, Sarah C.; Rocha, Rafael C. C.; Saint’Pierre, Tatiana D.; Bordignon, Suelen; Zibetti, Murilo; Trentini, Clarissa M.; Ávila, Daiana S.; Gioda, Adriana; Garcia, Solange C.

    2014-01-01

    Aging is often accompanied by cognitive impairments and influenced by oxidative status and chemical imbalances. Thus, this study was conducted to examine whether age-related cognitive deficit is associated with oxidative damage, especially with inhibition of the enzyme delta-aminolevulinate dehydratase (ALA-D), as well as to verify the influence of some metals in the enzyme activity and cognitive performance. Blood ALA-D activity, essential (Fe, Zn, Cu, Se) and non-essential metals (Pb, Cd, Hg, As, Cr, Ni, V) were measured in 50 elderly and 20 healthy young subjects. Cognitive function was assessed by tests from Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) battery and other. The elderly group presented decreased ALA-D activity compared to the young group. The index of ALA-D reactivation was similar to both study groups, but negatively associated with metals. The mean levels of essential metals were within the reference values, while the most toxic metals were above them in both groups. Cognitive function impairments were observed in elderly group and were associated with decreased ALA-D activity, with lower levels of Se and higher levels of toxic metals (Hg and V). Results suggest that the reduced ALA-D activity in elderly can be an additional factor involved in cognitive decline, since its inhibition throughout life could lead to accumulation of the neurotoxic compound ALA. Toxic metals were found to contribute to cognitive decline and also to influence ALA-D reactivation. PMID:25329536

  6. Cognitive loading affects motor awareness and movement kinematics but not locomotor trajectories during goal-directed walking in a virtual reality environment.

    PubMed

    Kannape, Oliver Alan; Barré, Arnaud; Aminian, Kamiar; Blanke, Olaf

    2014-01-01

    The primary purpose of this study was to investigate the effects of cognitive loading on movement kinematics and trajectory formation during goal-directed walking in a virtual reality (VR) environment. The secondary objective was to measure how participants corrected their trajectories for perturbed feedback and how participants' awareness of such perturbations changed under cognitive loading. We asked 14 healthy young adults to walk towards four different target locations in a VR environment while their movements were tracked and played back in real-time on a large projection screen. In 75% of all trials we introduced angular deviations of ±5° to ±30° between the veridical walking trajectory and the visual feedback. Participants performed a second experimental block under cognitive load (serial-7 subtraction, counter-balanced across participants). We measured walking kinematics (joint-angles, velocity profiles) and motor performance (end-point-compensation, trajectory-deviations). Motor awareness was determined by asking participants to rate the veracity of the feedback after every trial. In-line with previous findings in natural settings, participants displayed stereotypical walking trajectories in a VR environment. Our results extend these findings as they demonstrate that taxing cognitive resources did not affect trajectory formation and deviations although it interfered with the participants' movement kinematics, in particular walking velocity. Additionally, we report that motor awareness was selectively impaired by the secondary task in trials with high perceptual uncertainty. Compared with data on eye and arm movements our findings lend support to the hypothesis that the central nervous system (CNS) uses common mechanisms to govern goal-directed movements, including locomotion. We discuss our results with respect to the use of VR methods in gait control and rehabilitation.

  7. The Beneficial Effects of Additional Task Load, Positive Affect, and Instruction on the Attentional Blink

    ERIC Educational Resources Information Center

    Olivers, Christian N. L.; Nieuwenhuis, Sander

    2006-01-01

    The attentional blink reflects the impaired ability to identify the 2nd of 2 targets presented in close succession--a phenomenon that is generally thought to reflect a fundamental cognitive limitation. However, the fundamental nature of this impairment has recently been called into question by the counterintuitive finding that task-irrelevant…

  8. Impaired Cognition in Rats with Cortical Dysplasia: Additional Impact of Early-Life Seizures

    ERIC Educational Resources Information Center

    Lucas, Marcella M.; Lenck-Santini, Pierre-Pascal; Holmes, Gregory L.; Scott, Rod C.

    2011-01-01

    One of the most common and serious co-morbidities in patients with epilepsy is cognitive impairment. While early-life seizures are considered a major cause for cognitive impairment, it is not known whether it is the seizures, the underlying neurological substrate or a combination that has the largest impact on eventual learning and memory. Teasing…

  9. Treatment-resistant depression in adolescents: is the addition of cognitive behavioral therapy of benefit?

    PubMed Central

    Hetrick, Sarah E; Cox, Georgina R; Merry, Sally N

    2011-01-01

    Background Many young people with major depression fail first-line treatments. Treatment-resistant depression has various definitions in the literature but typically assumes nonresponse to medication. In young people, cognitive behavioral therapy (CBT) is the recommended first-line intervention, thus the definition of treatment resistance should be expanded. Therefore, our aim was to synthesize the existing evidence of any interventions for treatment-resistant depression, broadly defined, in children and adolescents and to investigate the effectiveness of CBT in this context. Methods We used Cochrane Collaboration methodology, with electronic searches of Medline, PsycINFO, Embase, and the Cochrane Depression Anxiety and Neurosis Group trials registers. Only randomized controlled trials were included, and were assessed for risk of bias. Meta- analysis was undertaken where possible and appropriate. Results Of 953 articles retrieved, four trials were eligible for inclusion. For one study, only the trial registration document was available, because the study was never completed. All other studies were well conducted with a low risk of bias, although one study had a high dropout rate. Two studies assessed the effect of adding CBT to medication. While an assertive trial of antidepressants does appear to lead to benefit, when compared with placebo, there was no significant advantage, in either study, or in a meta-analysis of data from these trials, that clearly demonstrated an additional benefit of CBT. The third trial showed little advantage of a tricyclic antidepressant over placebo in the context of an inpatient admission. Conclusion Few randomized controlled trials have investigated interventions for treatment-resistant depression in young people, and results from these show modest benefit from antidepressants with no additional benefit over medication from CBT. Overall, there is a lack of evidence about effective interventions to treat young people who have failed to

  10. Pattern Classification of Instantaneous Cognitive Task-load Through GMM Clustering, Laplacian Eigenmap and Ensemble SVMs.

    PubMed

    Zhang, Jianhua; Yin, Zhong; Wang, Rubin

    2016-05-03

    The identification of the temporal variations in human operator cognitive task-load (CTL) is crucial for preventing possible accidents in human-machine collaborative systems. Recent literature has shown that the change of discrete CTL level during human-machine system operations can be objectively recognized using neurophysiological data and supervised learning technique. The objective of this work is to design subject-specific multi-class CTL classifier to reveal the complex unknown relationship between the operator's task performance and neurophysiological features by combining target class labeling, physiological feature reduction and selection, and ensemble classification techniques. The psychophysiological data acquisition experiments were performed under multiple human-machine process control tasks. Four or five target classes of CTL were determined by using a Gaussian mixture model and three human performance variables. By using Laplacian eigenmap, a few salient EEG features were extracted, which and heart rate were used as the input features of the CTL classifier. Then multiple support vector machines were aggregated via majority voting to create an ensemble classifier for recognizing the CTL classes. Finally the obtained CTL classification results were compared with those of several existing methods. The results showed that the proposed methods are capable of deriving a reasonable number of target classes and low-dimensional optimal EEG features for individual human operator subjects.

  11. The roles of word concreteness and cognitive load on interhemispheric processes of recognition.

    PubMed

    Oliveira, J; Perea, M V; Ladera, V; Gamito, P

    2013-01-01

    Previous studies on hemispheric specialisation suggest that the cerebral hemispheres differ in the way verbal information is processed. There is also evidence that functional asymmetries are attributable to differences in stimulus properties and/or task complexity. To study these asymmetries in the domain of explicit recognition, concrete and abstract nouns were presented either in the right or left visual fields and recognised with foveal vision at different retention levels. We propose that different hemispheric mechanisms underlie the encoding of abstract and concrete information, which can be modulated by cognitive or mental load. To accomplish this goal, 92 right-handed undergraduate Portuguese students with normal or corrected-to-normal vision were randomly sampled from a university campus. The results showed that concrete words were discriminated better than abstract words when previously encoded in the right hemisphere for the longest retention interval between encoding and retrieval. These data suggest that there are different neural mechanisms for the semantic encoding of concrete and abstract concepts. The practical implications are discussed.

  12. Increasing cognitive load attenuates right arm swing in healthy human walking

    NASA Astrophysics Data System (ADS)

    Killeen, Tim; Easthope, Christopher S.; Filli, Linard; Lőrincz, Lilla; Schrafl-Altermatt, Miriam; Brugger, Peter; Linnebank, Michael; Curt, Armin; Zörner, Björn; Bolliger, Marc

    2017-01-01

    Human arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task-primarily involving left hemisphere structures-would reduce right arm swing only. We recorded gait in 83 healthy subjects aged 18-80 walking normally on a treadmill and while performing a congruent and incongruent Stroop task. The primary measure of arm swing asymmetry-an index based on both three-dimensional wrist trajectories in which positive values indicate proportionally smaller movements on the right-increased significantly under dual-task conditions in those aged 40-59 and further still in the over-60s, driven by reduced right arm flexion. Right arm swing attenuation appears to be the norm in humans performing a locomotor-cognitive dual-task, confirming a prominent role of the brain in locomotor behaviour. Women under 60 are surprisingly resistant to this effect, revealing unexpected gender differences atop the hierarchical chain of locomotor control.

  13. Increasing cognitive load attenuates right arm swing in healthy human walking

    PubMed Central

    Easthope, Christopher S.; Filli, Linard; Lőrincz, Lilla; Schrafl-Altermatt, Miriam; Brugger, Peter; Linnebank, Michael; Curt, Armin; Zörner, Björn; Bolliger, Marc

    2017-01-01

    Human arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task—primarily involving left hemisphere structures—would reduce right arm swing only. We recorded gait in 83 healthy subjects aged 18–80 walking normally on a treadmill and while performing a congruent and incongruent Stroop task. The primary measure of arm swing asymmetry—an index based on both three-dimensional wrist trajectories in which positive values indicate proportionally smaller movements on the right—increased significantly under dual-task conditions in those aged 40–59 and further still in the over-60s, driven by reduced right arm flexion. Right arm swing attenuation appears to be the norm in humans performing a locomotor-cognitive dual-task, confirming a prominent role of the brain in locomotor behaviour. Women under 60 are surprisingly resistant to this effect, revealing unexpected gender differences atop the hierarchical chain of locomotor control. PMID:28280596

  14. An Exploration of Students' Science Learning Interest Related to Their Cognitive Anxiety, Cognitive Load, Self-Confidence and Learning Progress Using Inquiry-Based Learning With an iPad

    NASA Astrophysics Data System (ADS)

    Hong, Jon-Chao; Hwang, Ming-Yueh; Tai, Kai-Hsin; Tsai, Chi-Ruei

    2017-01-01

    Based on the cognitive-affective theory, the present study designed a science inquiry learning model, predict-observe-explain (POE), and implemented it in an app called "WhyWhy" to examine the effectiveness of students' science inquiry learning practice. To understand how POE can affect the cognitive-affective learning process, as well as the learning progress, a pretest and a posttest were given to 152 grade 5 elementary school students. The students practiced WhyWhy during six sessions over 6 weeks, and data related to interest in learning science (ILS), cognitive anxiety (CA), and extraneous cognitive load (ECL) were collected and analyzed through confirmatory factor analysis with structure equation modeling. The results showed that students with high ILS have low CA and ECL. In addition, the results also indicated that students with a high level of self-confidence enhancement showed significant improvement in the posttest. The implications of this study suggest that by using technology-enhanced science learning, the POE model is a practical approach to motivate students to learn.

  15. Combining principles of Cognitive Load Theory and diagnostic error analysis for designing job aids: Effects on motivation and diagnostic performance in a process control task.

    PubMed

    Kluge, Annette; Grauel, Britta; Burkolter, Dina

    2013-03-01

    Two studies are presented in which the design of a procedural aid and the impact of an additional decision aid for process control were assessed. In Study 1, a procedural aid was developed that avoids imposing unnecessary extraneous cognitive load on novices when controlling a complex technical system. This newly designed procedural aid positively affected germane load, attention, satisfaction, motivation, knowledge acquisition and diagnostic speed for novel faults. In Study 2, the effect of a decision aid for use before the procedural aid was investigated, which was developed based on an analysis of diagnostic errors committed in Study 1. Results showed that novices were able to diagnose both novel faults and practised faults, and were even faster at diagnosing novel faults. This research contributes to the question of how to optimally support novices in dealing with technical faults in process control.

  16. Ocular accommodation and cognitive demand: An additional indicator besides pupil size and cardiovascular measures?

    PubMed Central

    Jainta, Stephanie; Hoormann, Joerg; Jaschinski, Wolfgang

    2008-01-01

    Background The aim of the present study was to assess accommodation as a possible indicator of changes in the autonomic balance caused by altered cognitive demand. Accounting for accommodative responses from a human factors perspective may be motivated by the interest of designing virtual image displays or by establishing an autonomic indicator that allows for remote measurement at the human eye. Heart period, pulse transit time, and the pupillary response were considered as reference for possible closed-loop accommodative effects. Cognitive demand was varied by presenting monocularly numbers at a viewing distance of 5 D (20 cm) which had to be read, added or multiplied; further, letters were presented in a "n-back" task. Results Cardiovascular parameters and pupil size indicated a change in autonomic balance, while error rates and reaction time confirmed the increased cognitive demand during task processing. An observed decrease in accommodation could not be attributed to the cognitive demand itself for two reasons: (1) the cognitive demand induced a shift in gaze direction which, for methodological reasons, accounted for a substantial part of the observed accommodative changes. (2) Remaining effects disappeared when the correctness of task processing was taken into account. Conclusion Although the expectation of accommodation as possible autonomic indicator of cognitive demand was not confirmed, the present results are informative for the field of applied psychophysiology noting that it seems not to be worthwhile to include closed-loop accommodation in future studies. From a human factors perspective, expected changes of accommodation due to cognitive demand are of minor importance for design specifications – of, for example, complex visual displays. PMID:18721478

  17. Influence of hydrophilic additives on the supersaturation and bioavailability of dutasteride-loaded hydroxypropyl-β-cyclodextrin nanostructures

    PubMed Central

    Kim, Min-Soo

    2013-01-01

    The objectives of this study were to develop a novel solid dutasteride formulation with improved physicochemical properties and oral bioavailability, and to examine the correlation between its in vitro dissolution and in vivo pharmacokinetic parameters. Hydroxypropyl-β-cyclodextrin (HP-β-CD) nanostructures with or without hydrophilic additives were manufactured using the supercritical antisolvent process. The dutasteride-loaded HP-β-CD nanoparticles formed aggregates with a mean particle size of less than 160 nm and a specific surface area greater than 100 m2/g. Increases in the supersaturation and dissolution rate for dutasteride were dependent on the type of additive; increases in maximum solubility and extended supersaturation were observed in dutasteride-loaded HP-β-CD nanostructures with hydroxypropylmethyl cellulose, whereas the dissolution rate was the highest for nanostructures containing d-α-tocopheryl polyethylene glycol 1000 succinate. In rats, the oral bioavailability of dutasteride increased with the supersaturation induced by the HP-β-CD nanostructures. In addition, compared with the in vitro drug release rate, the in vivo pharmacokinetic parameters were more closely correlated with in vitro parameters related to supersaturation (solubility). Further, the bioavailability of the dutasteride-loaded HP-β-CD nanostructures with hydroxypropylmethyl cellulose was similar to that of the commercially available soft gelatin capsule (Avodart®). In conclusion, preparation of dutasteride-loaded HP-β-CD nanostructures using the supercritical antisolvent process affords a viable alternative solid dosage form for dutasteride. PMID:23737668

  18. Influence of hydrophilic additives on the supersaturation and bioavailability of dutasteride-loaded hydroxypropyl-β-cyclodextrin nanostructures.

    PubMed

    Kim, Min-Soo

    2013-01-01

    The objectives of this study were to develop a novel solid dutasteride formulation with improved physicochemical properties and oral bioavailability, and to examine the correlation between its in vitro dissolution and in vivo pharmacokinetic parameters. Hydroxypropyl-β-cyclodextrin (HP-β-CD) nanostructures with or without hydrophilic additives were manufactured using the supercritical antisolvent process. The dutasteride-loaded HP-β-CD nanoparticles formed aggregates with a mean particle size of less than 160 nm and a specific surface area greater than 100 m(2)/g. Increases in the supersaturation and dissolution rate for dutasteride were dependent on the type of additive; increases in maximum solubility and extended supersaturation were observed in dutasteride-loaded HP-β-CD nanostructures with hydroxypropylmethyl cellulose, whereas the dissolution rate was the highest for nanostructures containing d-α-tocopheryl polyethylene glycol 1000 succinate. In rats, the oral bioavailability of dutasteride increased with the supersaturation induced by the HP-β-CD nanostructures. In addition, compared with the in vitro drug release rate, the in vivo pharmacokinetic parameters were more closely correlated with in vitro parameters related to supersaturation (solubility). Further, the bioavailability of the dutasteride-loaded HP-β-CD nanostructures with hydroxypropylmethyl cellulose was similar to that of the commercially available soft gelatin capsule (Avodart®). In conclusion, preparation of dutasteride-loaded HP-β-CD nanostructures using the supercritical antisolvent process affords a viable alternative solid dosage form for dutasteride.

  19. Manpower and Personnel Integration (MANPRINT) and Network Integration Evaluation 13.2: Observations on Cognitive Load in Mission Command

    DTIC Science & Technology

    2014-03-01

    JCR [Joint Capability Release] from the point of view of the FSO [Fire Support Officer...innovation provided a conceptual backdrop for MANPRINT data obtained during NIE 13.2 and subsequent discussion points . The next section provides...discusses the implications of the team’s MANPRINT results and conclusions, and (3) points the way to future work on cognitive load in mission command

  20. [CALCULATION OF RADIATION LOADS ON THE ANTHROPOMORPHIC PHANTOM ONBOARD THE SPACE STATION IN THE CASE OF ADDITIONAL SHIELDING].

    PubMed

    Kartashov, D A; Shurshakov, V A

    2015-01-01

    The paper presents the results of calculating doses from space ionizing radiation for a modeled orbital station cabin outfitted with an additional shield aimed to reduce radiation loads on cosmonaut. The shield is a layer with the mass thickness of -6 g/cm2 (mean density = 0.62 g/cm3) that covers the outer cabin wall and consists of wet tissues and towels used by cosmonauts for hygienic purposes. A tissue-equivalent anthropomorphic phantom imitates human body. Doses were calculated for the standard orbit of the International space station (ISS) with consideration of the longitudinal and transverse phantom orientation relative to the wall with or without the additional shield. Calculation of dose distribution in the human body improves prediction of radiation loads. The additional shield reduces radiation exposure of human critical organs by -20% depending on their depth and body spatial orientation in the ISS compartment.

  1. Dynamic Hilbert warping, a new measure of RR-interval signals evaluated in the cognitive load estimation.

    PubMed

    Ghaderyan, Peyvand; Abbasi, Ataollah

    2017-02-01

    RR interval (RRI) signals represent the time intervals between successive heart R-waves. These signals are influenced by many cognitive and psychological processes. In this study, a new technique based on the combination of empirical mode decomposition and dynamic Hilbert warping (DHW) was proposed to inference cognitive states from measured RRI signals. Moreover, a set of entropic and statistical measures was extracted to characterize the regularity and temporal distribution in the phase spectra and amplitude envelope of the analytic signals. The discriminating capability of the proposed method was studied in 45 healthy subjects. They performed an arithmetic task with five levels of difficulty. The study indicated the importance of phase information in cognitive load estimation (CLE). The new phase characteristics were able to extract hidden information from the RRI signals. The results revealed a striking decrease in DHW value with increasing load level. The entropic measures of analytic signal also showed an increasing trend as the mental load increased. Although, phase information had an ability to discriminate between more distinct levels as well as between more similar ones, amplitude information was effective only in discriminating between more distinct levels.

  2. Intuition and Moral Decision-Making - The Effect of Time Pressure and Cognitive Load on Moral Judgment and Altruistic Behavior.

    PubMed

    Tinghög, Gustav; Andersson, David; Bonn, Caroline; Johannesson, Magnus; Kirchler, Michael; Koppel, Lina; Västfjäll, Daniel

    2016-01-01

    Do individuals intuitively favor certain moral actions over others? This study explores the role of intuitive thinking-induced by time pressure and cognitive load-in moral judgment and behavior. We conduct experiments in three different countries (Sweden, Austria, and the United States) involving over 1,400 subjects. All subjects responded to four trolley type dilemmas and four dictator games involving different charitable causes. Decisions were made under time pressure/time delay or while experiencing cognitive load or control. Overall we find converging evidence that intuitive states do not influence moral decisions. Neither time-pressure nor cognitive load had any effect on moral judgments or altruistic behavior. Thus we find no supporting evidence for the claim that intuitive moral judgments and dictator game giving differ from more reflectively taken decisions. Across all samples and decision tasks men were more likely to make utilitarian moral judgments and act selfishly compared to women, providing further evidence that there are robust gender differences in moral decision-making. However, there were no significant interactions between gender and the treatment manipulations of intuitive versus reflective decision-making.

  3. Comprehension with Instructional Media for Middle School Science: Holistic Performative Design Strategy and Cognitive Load

    NASA Astrophysics Data System (ADS)

    Peterson, Matthew Owen

    This study identifies three distinct levels of text-image integration in page design in a linear relationship of lesser to greater integration: prose primary, prose subsumed, and fully integrated strategies. Science textbook pages were redesigned according to these holistic design strategies for 158 7th-grade students. There were three separate treatment tests, as well as a pre-test and post-test, and pilot tests with both undergraduate students and the subjects themselves. Subjects found the fully integrated strategy to produce the most visually interesting designs and the prose primary strategy to produce the least interesting, with prose subsumed definitively in between (according to 95% confidence intervals). The strategy employed significantly altered interest in science subject matter in one of three treatments (ANOVA, P=0.0446), where a Student's t-test revealed that the prose subsumed strategy produced higher interest in subject matter than prose primary. The strategy employed significantly altered comprehension of abstract relationships in one of three treatments (ANOVA, P=0.0202), where a Student's t-test revealed that the fully integrated strategy resulted in greater comprehension than prose primary. For the same treatment condition significant differences were found through ANOVA for factual-level knowledge (P=0.0289) but not conceptual-level knowledge ( P=0.0586). For factual-level knowledge prose primary resulted in lesser comprehension than both prose subsumed and fully integrated. Comprehension is defined according to cognitive load theory. No strategy impact on perception of task difficulty was found. This study was approved by North Carolina State University's Institutional Review Board and Wake County Public School System's Research Review Committee.

  4. Towards an index of cognitive efficacy EEG-based estimation of cognitive load among individuals experiencing cancer-related cognitive decline.

    PubMed

    Mathan, Santosh; Smart, Andrew; Ververs, Trish; Feuerstein, Michael

    2010-01-01

    This paper describes an effort to estimate variations in cognitive effort among cancer survivors experiencing treatment related cognitive decline. EEG-based cognitive state sensing algorithms were validated in the context of an experiment with 5 brain cancer and 5 breast cancer survivors. Workload was manipulated by varying text complexity and time pressure. Analysis indicates that EEG-based cognitive state sensing algorithms were able to distinguish between high and low cognitive workload with an average classification accuracy of 0.84. Results suggest that 5 to 10 channels of EEG can provide enough information to achieve classification accuracies exceeding 0.80. The highest density of informative sites were over the left temporal and mid to inferior frontal regions in the left hemisphere - regions that play a major role in language.

  5. The influence of vibration type, frequency, body position and additional load on the neuromuscular activity during whole body vibration.

    PubMed

    Ritzmann, Ramona; Gollhofer, Albert; Kramer, Andreas

    2013-01-01

    This study aimed to assess the influence of different whole body vibration (WBV) determinants on the electromyographic (EMG) activity during WBV in order to identify those training conditions that cause highest neuromuscular responses and therefore provide optimal training conditions. In a randomized cross-over study, the EMG activity of six leg muscles was analyzed in 18 subjects with respect to the following determinants: (1) vibration type (side-alternating vibration (SV) vs. synchronous vibration (SyV), (2) frequency (5-10-15-20-25-30 Hz), (3) knee flexion angle (10°-30°-60°), (4) stance condition (forefoot vs. normal stance) and (5) load variation (no extra load vs. additional load equal to one-third of the body weight). The results are: (1) neuromuscular activity during SV was enhanced compared to SyV (P < 0.05); (2) a progressive increase in frequency caused a progressive increase in EMG activity (P < 0.05); (3) the EMG activity was highest for the knee extensors when the knee joint was 60° flexed (P < 0.05); (4) for the plantar flexors in the forefoot stance condition (P < 0.05); and (5) additional load caused an increase in neuromuscular activation (P < 0.05). In conclusion, large variations of the EMG activation could be observed across conditions. However, with an appropriate adjustment of specific WBV determinants, high EMG activations and therefore high activation intensities could be achieved in the selected muscles. The combination of high vibration frequencies with additional load on an SV platform led to highest EMG activities. Regarding the body position, a knee flexion of 60° and forefoot stance appear to be beneficial for the knee extensors and the plantar flexors, respectively.

  6. A Cognitive Tool for Teaching the Addition/Subtraction of Common Fractions: A Model of Affordances

    ERIC Educational Resources Information Center

    Kong, Siu Cheung; Kwok, Lam For

    2005-01-01

    The aim of this research is to devise a cognitive tool for meeting the diverse needs of learners for comprehending new procedural knowledge. A model of affordances on teaching fraction equivalence for developing procedural knowledge for adding/subtracting fractions with unlike denominators was derived from the results of a case study of an initial…

  7. The Additive Benefit of Hypnosis and Cognitive-Behavioral Therapy in Treating Acute Stress Disorder

    ERIC Educational Resources Information Center

    Bryant, Richard A.; Moulds, Michelle L.; Guthrie, Rachel M.; Nixon, Reginald D. V.

    2005-01-01

    This research represents the first controlled treatment study of hypnosis and cognitive- behavioral therapy (CBT) of acute stress disorder (ASD). Civilian trauma survivors (N = 87) who met criteria for ASD were randomly allocated to 6 sessions of CBT, CBT combined with hypnosis (CBT-hypnosis), or supportive counseling (SC). CBT comprised exposure,…

  8. Cognitive and Language Development in an Additive-Bilingual Program: Report after Four Observations.

    ERIC Educational Resources Information Center

    Bamford, Kathryn W.; Mizokawa, Donald T.

    The fourth phase of a longitudinal study focusing on the cognitive and language development of children in a primary-grade Spanish immersion program (SIP) is reported. Subjects were the remaining 13 members of an SIP cohort beginning in 1987, 15 members of a standard program comparison classroom, 18 members of another class in the 1987 SIP cohort,…

  9. Human-Systems Integration (HSI) and the Network Integration Evaluations (NIEs), Part 2: A Deeper Dive into Mission Command Complexity and Cognitive Load

    DTIC Science & Technology

    2015-03-01

    perspective will not resolve the growing cognitive load problem. The previous paragraph addresses the long - term development of an objective CP- as... TERMS   NIE, mission command, complexity, cognitive load, human-systems integration 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT  UU...discussion to follow is this third level of HSI support. A Command Post (CP) is an example of a system-of-systems as that term is used above. The CP

  10. Marital Conflict, Allostatic Load, and the Development of Children's Fluid Cognitive Performance

    ERIC Educational Resources Information Center

    Hinnant, J. Benjamin; El-Sheikh, Mona; Keiley, Margaret; Buckhalt, Joseph A.

    2013-01-01

    Relations between marital conflict, children's respiratory sinus arrhythmia (RSA), and fluid cognitive performance were examined over 3 years to assess allostatic processes. Participants were 251 children reporting on marital conflict, baseline RSA, and RSA reactivity (RSA-R) to a lab challenge were recorded, and fluid cognitive performance…

  11. Reviewing the Role of Cognitive Load, Expertise Level, Motivation, and Unconscious Processing in Working Memory Performance

    ERIC Educational Resources Information Center

    Kuldas, Seffetullah; Hashim, Shahabuddin; Ismail, Hairul Nizam; Abu Bakar, Zainudin

    2015-01-01

    Human cognitive capacity is unavailable for conscious processing of every amount of instructional messages. Aligning an instructional design with learner expertise level would allow better use of available working memory capacity in a cognitive learning task. Motivating students to learn consciously is also an essential determinant of the capacity…

  12. Vectran Fiber Time-Dependent Behavior and Additional Static Loading Properties

    NASA Technical Reports Server (NTRS)

    Fette, Russell B.; Sovinski, Marjorie F.

    2004-01-01

    Vectran HS appears from literature and testing to date to be an ideal upgrade from Kevlar braided cords for many long-term, static-loading applications such as tie-downs on solar arrays. Vectran is a liquid crystalline polymer and exhibits excellent tensile properties. The material has been touted as a zero creep product. Testing discussed in this report does not support this statement, though the creep is on the order of four times slower than with similar Kevlar 49 products. Previous work with Kevlar and new analysis of Vectran testing has led to a simple predictive model for Vectran at ambient conditions. The mean coefficient of thermal expansion (negative in this case) is similar to Kevlar 49, but is not linear. A positive transition in the curve occurs near 100 C. Out-gassing tests show that the material performs well within parameters for most space flight applications. Vectran also offers increased abrasion resistance, minimal moisture regain, and similar UV degradation. The effects of material construction appear to have a dramatic effect in stress relaxation for braided Vectran. To achieve the improved relaxation rate, upgrades must also examine alternate construction or preconditioning methods. This report recommends Vectran HS as a greatly improved replacement material for applications where time-dependent relaxation is a major factor.

  13. Effects of domain-specific exercise load on speed and accuracy of a domain-specific perceptual-cognitive task.

    PubMed

    Schapschröer, M; Baker, J; Schorer, J

    2016-08-01

    In the context of perceptual-cognitive expertise it is important to know whether physiological loads influence perceptual-cognitive performance. This study examined whether a handball specific physical exercise load influenced participants' speed and accuracy in a flicker task. At rest and during a specific interval exercise of 86.5-90% HRmax, 35 participants (experts: n=8, advanced: n=13, novices, n=14) performed a handball specific flicker task with two types of patterns (structured and unstructured). For reaction time, results revealed moderate effect sizes for group, with experts reacting faster than advanced and advanced reacting faster than novices, and for structure, with structured videos being performed faster than unstructured ones. A significant interaction for structure×group was also found, with experts and advanced players faster for structured videos, and novices faster for unstructured videos. For accuracy, significant main effects were found for structure with structured videos solved more accurately. A significant interaction for structure×group was revealed, with experts and advanced more accurate for structured scenes and novices more accurate for unstructured scenes. A significant interaction was also found for condition×structure; at rest, unstructured and structured scenes were performed with the same accuracy while under physical exercise, structured scenes were solved more accurately. No other interactions were found. These results were somewhat surprising given previous work in this area, although the impact of a specific physical exercise on a specific perceptual-cognitive task may be different from those tested generally.

  14. Effects of expectation congruency on event-related potentials (ERPs) to facial expressions depend on cognitive load during the expectation phase.

    PubMed

    Lin, Huiyan; Schulz, Claudia; Straube, Thomas

    2016-10-01

    Previous studies have shown that event-related potentials (ERPs) to facial expressions are modulated by expectation (congruency) and that the ERP effects of expectation congruency are altered by cognitive tasks during the expectation phase. However, it is as yet unknown whether the congruency ERP effects can be modulated by the amount of cognitive load during the expectation phase. To address this question, electroencephalogram (EEG) was acquired when participants viewed fearful and neutral facial expressions. Before the presentation of facial expressions, a cue indicating the expression of a face and subsequently, an expectation interval without any cues were presented. Facial expressions were congruent with the cues in 75% of all trials. During the expectation interval, participants had to solve a cognitive task, in which several letters were presented for target letter detection. The letters were all the same under low load, but differed under high load. Event-related potential (ERP) results showed that the amount of cognitive load during the expectation phase altered the congruency effect in N2 and EPN amplitudes for fearful faces. Congruent as compared to incongruent fearful expressions elicited larger N2 and smaller EPN amplitudes under low load, but these congruency effects were not observed under high load. For neutral faces, a congruency effect in late positive potential (LPP) amplitudes was modulated by cognitive load during the expectation phase. The LPP was more positive for incongruent as compared to congruent faces under low load, but the congruency effect was not evident under high load. The findings indicate that congruency effects on ERPs are modulated by the amount of cognitive load the expectation phase and that this modulation is altered by facial expression.

  15. Extrinsic visual feedback and additional cognitive/physical demands affect single-limb balance control in individuals with ankle instability

    PubMed Central

    Hung, You-jou; Miller, Jacob

    2016-01-01

    AIM To investigate the impact of extrinsic visual feedback and additional cognitive/physical demands on single-limb balance in individuals with ankle instability. METHODS Sixteen subjects with ankle instability participated in the study. Ankle instability was identified using the Cumberland Ankle Instability Tool (CAIT). The subject’s unstable ankle was examined using the Athletic Single Leg Stability Test of the Biodex Balance System with 4 different protocols: (1) default setting with extrinsic visual feedback from the monitor; (2) no extrinsic visual feedback; (3) no extrinsic visual feedback with cognitive demands; and (4) no extrinsic visual feedback with physical demands. For the protocol with added cognitive demands, subjects were asked to continue subtracting 7 from a given number while performing the same test without extrinsic visual feedback. For the protocol with added physical demands, subjects were asked to pass and catch a basketball to and from the examiner while performing the same modified test. RESULTS The subject’s single-limb postural control varied significantly among different testing protocols (F = 103; P = 0.000). Subjects’ postural control was the worst with added physical demands and the best with the default condition with extrinsic visual feedback. Pairwise comparison shows subjects performed significantly worse in all modified protocols (P < 0.01 in all comparisons) compared to the default protocol. Results from all 4 protocols are significantly different from each other (P < 0.01) except for the comparison between the “no extrinsic visual feedback” and “no extrinsic visual feedback with cognitive demands” protocols. Comparing conditions without extrinsic visual feedback, adding a cognitive demand did not significantly compromise single-limb balance control but adding a physical demand did. Scores from the default protocol are significantly correlated with the results from all 3 modified protocols: No extrinsic visual

  16. Calcium Carbonate Nanoplate Assemblies with Directed High-Energy Facets: Additive-Free Synthesis, High Drug Loading, and Sustainable Releasing.

    PubMed

    Zhang, Jing; Li, Yu; Xie, Hao; Su, Bao-Lian; Yao, Bin; Yin, Yixia; Li, Shipu; Chen, Fang; Fu, Zhengyi

    2015-07-29

    Developing drug delivery systems (DDSs) with high drug-loading capacity and sustainable releasing is critical for long-term chemotherapeutic efficacy, and it still remains challenging. Herein, vaterite CaCO3 nanoplate assemblies with exposed high-energy {001} facets have been synthesized via a novel, additive-free strategy. The product shows a high doxorubicin-loading capacity (65%); the best of all the CaCO3-based DDSs so far. Also, the product's sustainable releasing performance and its inhibition of the initial burst release, together, endow it with long-term drug efficacy. The work may shed light on exposing directed high-energy facets for rationally designing of a drug delivery system with long-term efficacy.

  17. Design of Selective Gas Sensors Using Additive-Loaded In2O3 Hollow Spheres Prepared by Combinatorial Hydrothermal Reactions

    PubMed Central

    Kim, Sun-Jung; Hwang, In-Sung; Kang, Yun Chan; Lee, Jong-Heun

    2011-01-01

    A combinatorial hydrothermal reaction has been used to prepare pure and additive (Sb, Cu, Nb, Pd, and Ni)-loaded In2O3 hollow spheres for gas sensor applications. The operation of Pd- and Cu-loaded In2O3 sensors at 371 °C leads to selective H2S detection. Selective detection of CO and NH3 was achieved by the Ni-In2O3 sensor at sensing temperatures of 371 and 440 °C, respectively. The gas responses of six different sensors to NH3, H2S, H2, CO and CH4 produced unique gas sensing patterns that can be used for the artificial recognition of these gases. PMID:22346661

  18. The effect of trace element addition to mono-digestion of grass silage at high organic loading rates.

    PubMed

    Wall, David M; Allen, Eoin; Straccialini, Barbara; O'Kiely, Padraig; Murphy, Jerry D

    2014-11-01

    This study investigated the effect of trace element addition to mono-digestion of grass silage at high organic loading rates. Two continuous reactors were compared. The first mono-digested grass silage whilst the second operated in co-digestion, 80% grass silage with 20% dairy slurry (VS basis). The reactors were run for 65weeks with a further 5weeks taken for trace element supplementation for the mono-digestion of grass silage. The co-digestion reactor reported a higher biomethane efficiency (1.01) than mono-digestion (0.90) at an OLR of 4.0kgVSm(-3)d(-1) prior to addition of trace elements. Addition of cobalt, iron and nickel, led to an increase in the SMY in mono-digestion of grass silage by 12% to 404LCH4kg(-1)VS and attained a biomethane efficiency of 1.01.

  19. Rational molecular dynamics scheme for predicting optimum concentration loading of nano-additive in phase change materials

    NASA Astrophysics Data System (ADS)

    Rastogi, Monisha; Vaish, Rahul; Madhar, Niyaz Ahamad; Shaikh, Hamid; Al-Zahrani, S. M.

    2015-10-01

    The present study deals with the diffusion and phase transition behaviour of paraffin reinforced with carbon nano-additives namely graphene oxide (GO) and surface functionalized single walled carbon nanotubes (SWCNT). Bulk disordered systems of paraffin hydrocarbons impregnated with carbon nano-additives have been generated in realistic equilibrium conformations for potential application as latent heat storage systems. Ab initio molecular dynamics(MD) in conjugation with COMPASS forcefield has been implemented using periodic boundary conditions. The proposed scheme allows determination of optimum nano-additive loading for improving thermo-physical properties through analysis of mass, thermal and transport properties; and assists in determination of composite behaviour and related performance from microscopic point of view. It was observed that nanocomposites containing 7.8 % surface functionalised SWCNT and 55% GO loading corresponds to best latent heat storage system. The propounded methodology could serve as a by-pass route for economically taxing and iterative experimental procedures required to attain the optimum composition for best performance. The results also hint at the large unexplored potential of ab-initio classical MD techniques for predicting performance of new nanocomposites for potential phase change material applications.

  20. Stressing the mind: the effect of cognitive load and articulatory suppression on attentional guidance from working memory.

    PubMed

    Soto, David; Humphreys, Glyn W

    2008-07-01

    Four experiments explored the effect of cognitive load on the time course of top-down guidance of attention from working memory (WM). Observers had to search for a target presented among several distractors, with the target and distractor stimuli embedded inside different objects. On half of the trials, one of the distractor objects was cued by a matching item held in WM. When a single item was maintained in memory, search performance was impaired relative to a neutral baseline, where the memory and search displays did not match. These effects of WM on subsequent search were reduced by including a verbal suppression task during the WM and search displays, and by varying the WM load. The degree of competition for resources in WM is a key factor in determining the time course and magnitude of the interaction between WM and visual selection.

  1. Monitoring changes in cognitive load during reading: an event-related brain potential and reaction time analysis.

    PubMed

    Raney, G E

    1993-01-01

    Factors that contribute to cognitive load during reading were examined using a secondary task procedure. In three experiments, subjects read sets of passages twice in succession while auditory probes were presented. The N1-P2 and P300 components of the event-related brain potential and reaction time (RT) responses to secondary auditory probes were used as measures of load. N1-P2 responses indicated decreased load during the second reading, whereas P300 and RT responses indicated increased load during the second reading. The results are interpreted as reflecting changes in task demands. Lower level elements of the task, such as word recognition and local aspects of comprehension, required fewer resources during the second reading. The N1-P2 reflected this reduction in resource demands. By contrast, the amount of resources devoted to higher level processes, such as comparing the text with one's prior representation and updating memory, increased during the second reading. This resulted from task demands, which emphasized memory of the material. P300 and RT reflected this increase in higher level demands. Results are described in terms of attentional and task demands and are taken as support for a componential description of reading and task difficulty.

  2. Enhancing CBT for Chronic Insomnia: A Randomised Clinical Trial of Additive Components of Mindfulness or Cognitive Therapy.

    PubMed

    Wong, Mei Yin; Ree, Melissa J; Lee, Christopher W

    2016-09-01

    Although cognitive behavioural therapy (CBT) for insomnia has resulted in significant reductions in symptoms, most patients are not classified as good sleepers after treatment. The present study investigated whether additional sessions of cognitive therapy (CT) or mindfulness-based therapy (MBT) could enhance CBT in 64 participants with primary insomnia. All participants were given four sessions of standard CBT as previous research had identified this number of sessions as an optimal balance between therapist guidance and patient independence. Participants were then allocated to further active treatment (four sessions of CT or MBT) or a no further treatment control. The additional treatments resulted in significant improvements beyond CBT on self-report and objective measures of sleep and were well tolerated as evidenced by no dropouts from either treatment. The effect sizes for each of these additional treatments were large and clinically significant. The mean scores on the primary outcome measure, the Insomnia Severity Index, were 5.74 for CT and 6.69 for MBT, which are within the good-sleeper range. Treatment effects were maintained at follow-up. There were no significant differences between CT and MBT on any outcome measure. These results provide encouraging data on how to enhance CBT for treatment of insomnia. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Estimating cognitive load during self-regulation of brain activity and neurofeedback with therapeutic brain-computer interfaces.

    PubMed

    Bauer, Robert; Gharabaghi, Alireza

    2015-01-01

    Neurofeedback (NFB) training with brain-computer interfaces (BCIs) is currently being studied in a variety of neurological and neuropsychiatric conditions in an aim to reduce disorder-specific symptoms. For this purpose, a range of classification algorithms has been explored to identify different brain states. These neural states, e.g., self-regulated brain activity vs. rest, are separated by setting a threshold parameter. Measures such as the maximum classification accuracy (CA) have been introduced to evaluate the performance of these algorithms. Interestingly enough, precisely these measures are often used to estimate the subject's ability to perform brain self-regulation. This is surprising, given that the goal of improving the tool that differentiates between brain states is different from the aim of optimizing NFB for the subject performing brain self-regulation. For the latter, knowledge about mental resources and work load is essential in order to adapt the difficulty of the intervention accordingly. In this context, we apply an analytical method and provide empirical data to determine the zone of proximal development (ZPD) as a measure of a subject's cognitive resources and the instructional efficacy of NFB. This approach is based on a reconsideration of item-response theory (IRT) and cognitive load theory for instructional design, and combines them with the CA curve to provide a measure of BCI performance.

  4. Exploring the Impact of Prior Knowledge and Appropriate Feedback on Students' Perceived Cognitive Load and Learning Outcomes: Animation-based earthquakes instruction

    NASA Astrophysics Data System (ADS)

    Yeh, Ting-Kuang; Tseng, Kuan-Yun; Cho, Chung-Wen; Barufaldi, James P.; Lin, Mei-Shin; Chang, Chun-Yen

    2012-07-01

    The aim of this study was to develop an animation-based curriculum and to evaluate the effectiveness of animation-based instruction; the report involved the assessment of prior knowledge and the appropriate feedback approach, for the purpose of reducing perceived cognitive load and improving learning. The curriculum was comprised of five subunits designed to teach the 'Principles of Earthquakes.' Each subunit consisted of three modules: evaluation of prior knowledge with/without in-time feedback; animation-based instruction; and evaluation of learning outcomes with feedback. The 153 participants consisted of 10th grade high-school students. Seventy-eight students participated in the animation-based instruction, involving assessment of prior knowledge and appropriate feedback mechanism (APA group). A total of 75 students participated in animation-based learning that did not take into account their prior knowledge (ANPA group). The effectiveness of the instruction was then evaluated by using a Science Conception Test (SCT), a self-rating cognitive load questionnaire (CLQ), as well as a structured interview. The results indicated that: (1) Students' perceived cognitive load was reduced effectively through improving their prior knowledge by providing appropriate feedback. (2) When students perceived lower levels of cognitive load, they showed better learning outcome. The result of this study revealed that students of the APA group showed better performance than those of the ANPA group in an open-ended question. Furthermore, students' perceived cognitive load was negatively associated with their learning outcomes.

  5. Cognitive Processing Load as a Determinant of Stuttering: Summary of a Research Programme

    ERIC Educational Resources Information Center

    Bosshardt, Hans-Georg

    2006-01-01

    The present paper integrates the results of experimental studies in which cognitive differences between stuttering and nonstuttering adults were investigated. In a monitoring experiment it was found that persons who stutter encode semantic information more slowly than nonstuttering persons. In dual-task experiments the two groups were compared in…

  6. Instructional Efficiency of Changing Cognitive Load in an Out-of-School Laboratory

    ERIC Educational Resources Information Center

    Scharfenberg, Franz-Josef; Bogner, Franz X.

    2010-01-01

    Our research objective focused on monitoring students' mental effort and cognitive achievement to unveil potential effects of an instructional change in an out-of-school laboratory offering gene technology modules. Altogether, 231 students (12th graders) attended our day-long hands-on module. Within a quasi-experimental design, a treatment group…

  7. Collaboration Modality, Cognitive Load, and Science Inquiry Learning in Virtual Inquiry Environments

    ERIC Educational Resources Information Center

    Erlandson, Benjamin E.; Nelson, Brian C.; Savenye, Wilhelmina C.

    2010-01-01

    Educational multi-user virtual environments (MUVEs) have been shown to be effective platforms for situated science inquiry curricula. While researchers find MUVEs to be supportive of collaborative scientific inquiry processes, the complex mix of multi-modal messages present in MUVEs can lead to cognitive overload, with learners unable to…

  8. Collaborative Learning Using a Project across Multiple Business Courses: A Cognitive Load and Knowledge Convergence Approach

    ERIC Educational Resources Information Center

    Bhowmick, Sandeep; Chandra, Aruna; Harper, Jeffrey S.; Sweetin, Vernon

    2015-01-01

    Four business professors at a state university in the Midwestern United States launched a collaborative learning project grounded in cognitive learning theory and knowledge convergence theory with the objective of assessing student learning gains in cross-functional knowledge (CFK), course-related knowledge (CRK), and overall satisfaction with…

  9. Using Pictorial Mnemonics in the Learning of Tax: A Cognitive Load Perspective

    ERIC Educational Resources Information Center

    Smith, Bernadette; Shimeld, Sonia

    2014-01-01

    The scope and complexity of the Australian taxation system (as with other tax regimes) is daunting for many accounting students. This paper documents the implementation of new practices that were initiated in an effort to address some of the challenges faced by undergraduate students studying taxation. Based on the principles of cognitive load…

  10. Effects of maternally exposed colouring food additives on cognitive performance in rats.

    PubMed

    Doguc, Duygu Kumbul; Ceyhan, Betul Mermi; Ozturk, Mustafa; Gultekin, Fatih

    2013-08-01

    Artificial food colourings and additives (AFCAs) have long been suggested to adversely affect the learning and behaviour in children. In this study, we aimed to provide additional data to clarify the possible side effects of colouring additives on behaviour and memory. We administered acceptable daily intake values of AFCAs as a mixture (Eritrosin, Ponceau 4R, Allura Red AC, Sunset Yellow FCF, Tartrazin, Amaranth, Brilliant Blue, Azorubin and Indigotin) to female rats before and during gestation and then tested their effects on behaviour and on spatial working memory in their offspring. Effects on spatial learning and memory were evaluated by Morris water maze, behavioural effects were evaluated by open-field test and forced swim test. Our results showed that commonly used artificial food colourings have no adverse effects on spatial working memory and did not create a depressive behaviour in offspring. But they showed a few significant effects on locomotor activity as AFCAs increased some parameters of locomotor activity.

  11. A New Approach to Analyzing the Cognitive Load in Physics Problems

    NASA Astrophysics Data System (ADS)

    Teodorescu, Raluca

    2010-02-01

    I will present a Taxonomy of Introductory Physics Problems (TIPP), which relates physics problems to the cognitive processes and the knowledge required to solve them. TIPP was created for designing and clarifying educational objectives, for developing assessments to evaluate components of the problem-solving process, and for guiding curriculum design in introductory physics courses. To construct TIPP, I considered processes that have been identified either by cognitive science and expert-novice research or by direct observation of students' behavior while solving physics problems. Based on Marzano and Kendall's taxonomy [1], I developed a procedure to classify physics problems according to the cognitive processes that they involve and the knowledge to which they refer. The procedure is applicable to any physics problem and its validity and reliability have been confirmed. This algorithm was then used to build TIPP, which is a database that contains text-based and research-based physics problems and explains their relationship to cognitive processes and knowledge. TIPP has been used in the years 2006--2009 to reform the first semester of the introductory algebra-based physics course at The George Washington University. The reform targeted students' cognitive development and attitudes improvement. The methodology employed in the course involves exposing students to certain types of problems in a variety of contexts with increasing complexity. To assess the effectiveness of our approach, rubrics were created to evaluate students' problem-solving abilities and the Colorado Learning Attitudes about Science Survey (CLASS) was administered pre- and post-instruction to determine students' shift in dispositions towards learning physics. Our results show definitive gains in the areas targeted by our curricular reform.[4pt] [1] R.J. Marzano and J.S. Kendall, The New Taxonomy of Educational Objectives, 2^nd Ed., (Corwin Press, Thousand Oaks, 2007). )

  12. Effects of memory load on event-related patterns of 40-Hz EEG during cognitive and motor tasks.

    PubMed

    De Pascalis, V; Ray, W J

    1998-05-01

    The present study describes a phasic event-related synchronization (ERS) in the gamma band (36-44 Hz) induced by the onset of probe visual stimuli. The experiment consisted of two experimental tasks with high and low memory-load in which a geometrical figure (S1) was held in memory for comparison with a subsequent stimulus (S2). In each task a Go-NoGo paradigm was used with a Same-Different discrimination task. The aim of the study was to examine the influence on 40-Hz ERS of stimulus type ('Same-Different') and of response (Go-NoGo) task as moderated by activation or effort level (high/low memory-load). The investigation was carried out in 27 women. The EEG was recorded from FP1, FP2, F3, F4, P3, P4, O1 and O2 scalp sites referenced to linked earlobes. As a manipulation check for activation level, we recorded heart rate (HR) during the S1-S2 period. A main peak of activity was found around 160 ms with a maximum at occipital sites. The amplitude of this peak was higher in the high memory-load as compared to the low memory-load condition. This difference was manifested mainly at F3 and O2 scalp sites. A larger 40-Hz peak at F3 was also found in the Go compared to the NoGo condition. No 40-Hz ERS differences between Same and Different trials were observed. The HR was found sensitive to the stimulus type showing a greater HR deceleration response to S2 for Same trials, as compared to Different ones. In parallel with 40-Hz ERS response, the HR deceleration was more pronounced for the high memory-load as compared to the low memory-load condition. The results indicate that the 40-Hz ERS is dependent upon both memory-load and motor responding. The influence of memory load on cognitive (Same-Different) and motor response (Go-NoGo) variables is discussed.

  13. Working memory load-related electroencephalographic parameters can differentiate progressive from stable mild cognitive impairment.

    PubMed

    Missonnier, P; Deiber, M-P; Gold, G; Herrmann, F R; Millet, P; Michon, A; Fazio-Costa, L; Ibañez, V; Giannakopoulos, P

    2007-12-05

    Recent studies described several changes of endogenous event-related potentials (ERP) and brain rhythm synchronization during memory activation in patients with Alzheimer's disease (AD). To examine whether memory-related EEG parameters may predict cognitive decline in mild cognitive impairment (MCI), we assessed P200 and N200 latencies as well as beta event-related synchronization (ERS) in 16 elderly controls (EC), 29 MCI cases and 10 patients with AD during the successful performance of a pure attentional detection task as compared with a highly working memory demanding two-back task. At 1 year follow-up, 16 MCI patients showed progressive cognitive decline (PMCI) and 13 remained stable (SMCI). Both P200 and N200 latencies in the two-back task were longer in PMCI and AD cases compared with EC and SMCI cases. During the interval 1000 ms to 1700 ms after stimulus, beta ERS at parietal electrodes was of lower amplitude in PMCI and AD compared with EC and SMCI cases. Univariate models showed that P200, N200 and log% beta values were significantly related to the SMCI/PMCI distinction with areas under the receiver operating characteristic curve of 0.93, 0.78 and 0.72, respectively. The combination of all three EEG hallmarks was the stronger predictor of MCI deterioration with 90% of correctly classified MCI cases. Our data reveal that PMCI and clinically overt AD share the same pattern of working memory-related EEG activation characterized by increased P200-N200 latencies and decreased beta ERS. They also show that P200 latency during the two-back task may be a simple and promising EEG marker of rapid cognitive decline in MCI.

  14. Cognitive load and emotional processing in generalized anxiety disorder: electrocortical evidence for increased distractibility.

    PubMed

    MacNamara, Annmarie; Proudfit, Greg Hajcak

    2014-08-01

    Generalized anxiety disorder (GAD) may be characterized by emotion regulation deficits attributable to an imbalance between top-down (i.e., goal-driven) and bottom-up (i.e., stimulus-driven) attention. In prior work, these attentional processes were examined by presenting unpleasant and neutral pictures within a working memory paradigm. The late positive potential (LPP) measured attention toward task-irrelevant pictures. Results from this prior work showed that working memory load reduced the LPP across participants; however, this effect was attenuated for individuals with greater self-reported state anxiety, suggesting reduced top-down control. In the current study, the same paradigm was used with 106 medication-free female participants-71 with GAD and 35 without GAD. Unpleasant pictures elicited larger LPPs, and working memory load reduced the picture-elicited LPP. Compared with healthy controls, participants with GAD showed large LPPs to unpleasant pictures presented under high working memory load. Self-reported symptoms of anhedonic depression were related to a reduced effect of working memory load on the LPP elicited by neutral pictures. These results indicate that individuals with GAD show less flexible modulation of attention when confronted with unpleasant stimuli. Furthermore, among those with GAD, anhedonic depression may broaden attentional deficits to neutral distracters.

  15. The influence of an additional load on time and force changes in the ground reaction force during the countermovement vertical jump.

    PubMed

    Vaverka, Frantisek; Jakubsova, Zlatava; Jandacka, Daniel; Zahradnik, David; Farana, Roman; Uchytil, Jaroslav; Supej, Matej; Vodicar, Janez

    2013-01-01

    The aim of this study was to determine how an additional load influences the force-vs-time relationship of the countermovement vertical jump (CMVJ). The participants that took part in the experiment were 18 male university students who played sport recreationally, including regular games of volleyball. They were asked to perform a CMVJ without involving the arms under four conditions: without and with additional loads of 10%, 20%, and 30% of their body weight (BW). The vertical component of the ground reaction force (GRF) was measured by a force plate. The GRF was used to calculate the durations of the preparatory, braking, and acceleration phases, the total duration of the jump, force impulses during the braking and acceleration phases, average forces during the braking and acceleration phases, and the maximum force of impact at landing. Results were evaluated using repeated-measures ANOVA. Increasing the additional load prolonged both the braking and acceleration phases of the jump, with statistically significant changes in the duration of the acceleration phase found for an additional load of 20% BW. The magnitude of the force systematically and significantly increased with the additional load. The force impulse during the acceleration phase did not differ significantly between jumps performed with loads of 20% and 30% BW. The results suggest that the optimal additional load for developing explosive strength in vertical jumping ranges from 20% to 30% of BW, with this value varying between individual subjects.

  16. The myopia of crowds: Cognitive load and collective evaluation of answers on Stack Exchange.

    PubMed

    Burghardt, Keith; Alsina, Emanuel F; Girvan, Michelle; Rand, William; Lerman, Kristina

    2017-01-01

    Crowds can often make better decisions than individuals or small groups of experts by leveraging their ability to aggregate diverse information. Question answering sites, such as Stack Exchange, rely on the "wisdom of crowds" effect to identify the best answers to questions asked by users. We analyze data from 250 communities on the Stack Exchange network to pinpoint factors affecting which answers are chosen as the best answers. Our results suggest that, rather than evaluate all available answers to a question, users rely on simple cognitive heuristics to choose an answer to vote for or accept. These cognitive heuristics are linked to an answer's salience, such as the order in which it is listed and how much screen space it occupies. While askers appear to depend on heuristics to a greater extent than voters when choosing an answer to accept as the most helpful one, voters use acceptance itself as a heuristic, and they are more likely to choose the answer after it has been accepted than before that answer was accepted. These heuristics become more important in explaining and predicting behavior as the number of available answers to a question increases. Our findings suggest that crowd judgments may become less reliable as the number of answers grows.

  17. The myopia of crowds: Cognitive load and collective evaluation of answers on Stack Exchange

    PubMed Central

    Burghardt, Keith; Alsina, Emanuel F.; Girvan, Michelle; Rand, William; Lerman, Kristina

    2017-01-01

    Crowds can often make better decisions than individuals or small groups of experts by leveraging their ability to aggregate diverse information. Question answering sites, such as Stack Exchange, rely on the “wisdom of crowds” effect to identify the best answers to questions asked by users. We analyze data from 250 communities on the Stack Exchange network to pinpoint factors affecting which answers are chosen as the best answers. Our results suggest that, rather than evaluate all available answers to a question, users rely on simple cognitive heuristics to choose an answer to vote for or accept. These cognitive heuristics are linked to an answer’s salience, such as the order in which it is listed and how much screen space it occupies. While askers appear to depend on heuristics to a greater extent than voters when choosing an answer to accept as the most helpful one, voters use acceptance itself as a heuristic, and they are more likely to choose the answer after it has been accepted than before that answer was accepted. These heuristics become more important in explaining and predicting behavior as the number of available answers to a question increases. Our findings suggest that crowd judgments may become less reliable as the number of answers grows. PMID:28301531

  18. Cognitive Load and Listening Effort: Concepts and Age-Related Considerations.

    PubMed

    Lemke, Ulrike; Besser, Jana

    2016-01-01

    Listening effort has been recognized as an important dimension of everyday listening, especially with regard to the comprehension of spoken language. At constant levels of comprehension performance, the level of effort exerted and perceived during listening can differ considerably across listeners and situations. In this article, listening effort is used as an umbrella term for two different types of effort that can arise during listening. One of these types is processing effort, which is used to denote the utilization of "extra" mental processing resources in listening conditions that are adverse for an individual. A conceptual description is introduced how processing effort could be defined in terms of situational influences, the listener's auditory and cognitive resources, and the listener's personal state. Also, the proposed relationship between processing effort and subjectively perceived listening effort is discussed. Notably, previous research has shown that the availability of mental resources, as well as the ability to use them efficiently, changes over the course of adult aging. These common age-related changes in cognitive abilities and their neurocognitive organization are discussed in the context of the presented concept, especially regarding situations in which listening effort may be increased for older people.

  19. Subthalamic nucleus involvement in executive functions with increased cognitive load: a subthalamic nucleus and anterior cingulate cortex depth recording study.

    PubMed

    Aulická, Stefania Rusnáková; Jurák, Pavel; Chládek, Jan; Daniel, Pavel; Halámek, Josef; Baláž, Marek; Bočková, Martina; Chrastina, Jan; Rektor, Ivan

    2014-10-01

    We studied the appearance of broadband oscillatory changes (ranging 2-45 Hz) induced by a cognitive task with two levels of complexity. The event-related de/synchronizations (ERD/S) in the subthalamic nucleus (STN) and in the anterior cingulate cortex (ACC) were evaluated in an executive function test. Four epilepsy surgery candidates with intracerebral electrodes implanted in the ACC and three Parkinson's disease patients with externalized deep brain stimulation electrodes implanted in the STN participated in the study. A Flanker test (FT) with visual stimuli (arrows) was performed. Subjects reacted to four types of stimuli presented on the monitor by pushing the right or left button: congruent arrows to the right or left side (simple task) and incongruent arrows to the right or left side (more difficult complex task). We explored the activation of STN and the activation of the ACC while processing the FT. Both conditions, i.e. congruent and incongruent, induced oscillatory changes in the ACC and also STN with significantly higher activation during incongruent trial. At variance with the ACC, in the STN not only the ERD beta but also the ERD alpha activity was significantly more activated by the incongruent condition. In line with our earlier studies, the STN appears to be involved in activities linked with increased cognitive load. The specificity and complexity of task-related activation of the STN might indicate the involvement of the STN in processes controlling human behaviour, e.g. in the selection and inhibition of competing alternatives.

  20. The framing of drivers' route choices when travel time information is provided under varying degrees of cognitive load.

    PubMed

    Katsikopoulos, K V; Duse-Anthony, Y; Fisher, D L; Duffy, S A

    2000-01-01

    In two experiments, participants chose between staying on a main route with a certain travel time and diverting to an alternative route that could take a range of travel times. In the first experiment, travel time information was displayed on a sheet of paper to participants seated at a desk. In the second experiment, the same information was displayed in a virtual environment through which participants drove. Overall, participants were risk-averse when the average travel time along the alternative route was shorter than the certain travel time of the main route but risk-seeking when the average travel time of the alternative route was longer than the certain travel time along the main route. In the second experiment, in which cognitive load was higher, participants simplified their decision-making strategies. A simple probabilistic model describes the risk-taking behavior and the load effects. Actual or potential applications of this research include the development of efficient travel time information systems for drivers.

  1. Exercise benefits for the aging brain depend on the accompanying cognitive load: insights from sleep electroencephalogram.

    PubMed

    Horne, Jim

    2013-11-01

    Although exercise clearly offsets aging effects on the body, its benefits for the aging brain are likely to depend on the extent that physical activity (especially locomotion) facilitates multisensory encounters, curiosity, and interactions with novel environments; this is especially true for exploratory activity, which occupies much of wakefulness for most mammals in the wild. Cognition is inseparable from physical activity, with both interlinked to promote neuroplasticity and more successful brain aging. In these respects and for humans, exercising in a static, featureless, artificially lit indoor setting contrasts with exploratory outdoor walking within a novel environment during daylight. However, little is known about the comparative benefits for the aging brain of longer-term daily regimens of this latter nature including the role of sleep, to the extent that sleep enhances neuroplasticity as shown in short-term laboratory studies. More discerning analyses of sleep electroencephalogram (EEG) slow-wave activity especially 0.5-2-Hz activity would provide greater insights into use-dependent recovery processes during longer-term tracking of these regimens and complement slower changing waking neuropsychologic and resting functional magnetic resonance imaging (fMRI) measures, including those of the brain's default mode network. Although the limited research only points to ephemeral small sleep EEG effects of pure exercise, more enduring effects seem apparent when physical activity incorporates cognitive challenges. In terms of "use it or lose it," curiosity-driven "getting out and about," encountering, interacting with, and enjoying novel situations may well provide the brain with its real exercise, further reflected in changes to the dynamics of sleep.

  2. Acute effect of Snus on physical performance and perceived cognitive load on amateur footballers.

    PubMed

    Morente-Sánchez, J; Zandonai, T; Mateo-March, M; Sanabria, D; Sánchez-Muñoz, C; Chiamulera, C; Zabala Díaz, M

    2015-08-01

    Smokeless tobacco (Snus) is a substance that contains nicotine, which has been placed on World Anti-Doping Agency's 2014 Monitoring Program. A proliferation of nicotine use in sport has been observed in recent years, but little is known regarding its effects, especially on football players' performance. Therefore, the aim of this study was to assess the effect of Snus on physical performance, heart rate variability, subjective activation, mental fatigue, and perceived readiness before a physical test in non-smoker, non-Snus user, amateur football players. Participants were administered either Snus or placebo 40 min prior to a fitness test battery (handgrip test, countermovement jump, agility test, and Yo-Yo intermittent recovery test). Results showed that Snus intake (compared with placebo) increased perceived mental fatigue level and mental load, and reduced perceived readiness level and heart rate variability. No significant differences between the two experimental conditions were found in either performance in the physical tests or perceived physical fatigue levels. In light of these results, Snus could not be considered an ergogenic substance. On the contrary, based on the extant evidence linking mental load and fatigue with physical performance, we argue that the observed negative effects on mental fatigue, perceived readiness, and heart rate variability should be considered.

  3. Gender Differences in Cognitive Load and Competition Anxiety Affect 6th Grade Students' Attitude toward Playing and Intention to Play at a Sequential or Synchronous Game

    ERIC Educational Resources Information Center

    Hwang, Ming-Yueh; Hong, Jon-Chao; Cheng, Hao-Yueh; Peng, Yu-Chi; Wu, Nien-Chen

    2013-01-01

    Do girls have more competition anxiety and exogenous cognitive load than equally able boys during the playing of stressful competitive on-line games? This question led to the adoption of a technology acceptance model to compare the influence factors of competitors in sequential and synchronous games. Confirmatory factor analysis of the data on 220…

  4. RoLo: A Dictionary Interface that Minimizes Extraneous Cognitive Load of Lookup and Supports Incidental and Incremental Learning of Vocabulary

    ERIC Educational Resources Information Center

    Dang, Thanh-Dung; Chen, Gwo-Dong; Dang, Giao; Li, Liang-Yi; Nurkhamid

    2013-01-01

    Dictionary use can improve reading comprehension and incidental vocabulary learning. Nevertheless, great extraneous cognitive load imposed by the search process may reduce or even prevent the improvement. With the help of technology, dictionary users can now instantly access the meaning list of a searched word using a mouse click. However, they…

  5. Advancing Lie Detection by Inducing Cognitive Load on Liars: A Review of Relevant Theories and Techniques Guided by Lessons from Polygraph-Based Approaches

    PubMed Central

    Walczyk, Jeffrey J.; Igou, Frank P.; Dixon, Alexa P.; Tcholakian, Talar

    2013-01-01

    This article critically reviews techniques and theories relevant to the emerging field of “lie detection by inducing cognitive load selectively on liars.” To help these techniques benefit from past mistakes, we start with a summary of the polygraph-based Controlled Question Technique (CQT) and the major criticisms of it made by the National Research Council (2003), including that it not based on a validated theory and administration procedures have not been standardized. Lessons from the more successful Guilty Knowledge Test are also considered. The critical review that follows starts with the presentation of models and theories offering insights for cognitive lie detection that can undergird theoretically load-inducing approaches. This is followed by evaluation of specific research-based, load-inducing proposals, especially for their susceptibility to rehearsal and other countermeasures. To help organize these proposals and suggest new direction for innovation and refinement, a theoretical taxonomy is presented based on the type of cognitive load induced in examinees (intrinsic or extraneous) and how open-ended the responses to test items are. Finally, four recommendations are proffered that can help researchers and practitioners to avert the corresponding mistakes with the CQT and yield new, valid cognitive lie detection technologies. PMID:23378840

  6. Cognitive Load and Learning Effects of Having Students Organize Pictures and Words in Multimedia Environments: The Role of Student Interactivity and Feedback

    ERIC Educational Resources Information Center

    Moreno, Roxana; Valdez, Alfred

    2005-01-01

    The cognitive load and learning effects of dual-code and interactivity--two multimedia methods intended to promote meaningful learning--were examined. In Experiment 1, college students learned about the causal chain of events leading to the process of lightning formation with a set of words and corresponding pictures (Group WP), pictures (Group…

  7. The Impact of Control Belief and Learning Disorientation on Cognitive Load: The Mediating Effect of Academic Emotions in Two Types of Hypermedia Learning Environments

    ERIC Educational Resources Information Center

    Sunawan; Xiong, Junmei

    2017-01-01

    The present study tested the influence of control belief, learning disorientation, and academic emotions on cognitive load in two types of concept-map structures within hypermedia learning environment. Four hundred and eighty-five students were randomly assigned to two groups: 245 students in the hierarchical group and 240 students in the…

  8. Effects of WOE Presentation Types Used in Pre-Training on the Cognitive Load and Comprehension of Content in Animation-Based Learning Environments

    ERIC Educational Resources Information Center

    Jung, Jung,; Kim, Dongsik; Na, Chungsoo

    2016-01-01

    This study investigated the effectiveness of various types of worked-out examples used in pre-training to optimize the cognitive load and enhance learners' comprehension of the content in an animation-based learning environment. An animation-based learning environment was developed specifically for this study. The participants were divided into…

  9. Students' Scientific Epistemic Beliefs, Online Evaluative Standards, and Online Searching Strategies for Science Information: The Moderating Role of Cognitive Load Experience

    ERIC Educational Resources Information Center

    Hsieh, Ya-Hui; Tsai, Chin-Chung

    2014-01-01

    The purpose of this study is to examine the moderating role of cognitive load experience between students' scientific epistemic beliefs and information commitments, which refer to online evaluative standards and online searching strategies. A total of 344 science-related major students participated in this study. Three questionnaires were…

  10. The Impact of Instructional Design on College Students' Cognitive Load and Learning Outcomes in a Large Food Science and Human Nutrition Course

    ERIC Educational Resources Information Center

    Andrade, Jeanette; Huang, Wen-Hao David; Bohn, Dawn M.

    2015-01-01

    The effective design of course materials is critical for student learning, especially for large lecture introductory courses. This quantitative study was designed to explore the effect multimedia and content difficulty has on students' cognitive load and learning outcomes. College students (n = 268) were randomized into 1 of 3 multimedia groups:…

  11. Do Cheaters Never Prosper? The Impact of Examples, Expertise, and Cognitive Load on Cryptomnesia and Inadvertent Self-Plagiarism of Creative Tasks

    ERIC Educational Resources Information Center

    Dow, Gayle T.

    2015-01-01

    Previous work has shown that the presence of examples may lead to cryptomnesia, or inadvertent plagiarism, on creative tasks. Various experiential and environmental attributes may magnify this finding. For instance, novices, with limited knowledge, may be more prone to inadvertently plagiarize examples, and increases in cognitive load may result…

  12. Is Single or Dual Channel with Different English Proficiencies Better for English Listening Comprehension, Cognitive Load and Attitude in Ubiquitous Learning Environment?

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng; Tseng, Kuo-Hung; Tseng, Ju-Shih

    2011-01-01

    The purpose of the present study was to examine the effects of English proficiency (low vs. high) and material presentation mode (single channel vs. dual channel) on English listening comprehension, cognitive load and learning attitude in a ubiquitous learning environment. An experimental learning activity was implemented using PDA as a learning…

  13. A Conceptual Paper on the Application of the Picture Word Inductive Model Using Bruner's Constructivist View of Learning and the Cognitive Load Theory

    ERIC Educational Resources Information Center

    Jiang, Xuan; Perkins, Kyle

    2013-01-01

    Bruner's constructs of learning, specifically the structure of learning, spiral curriculum, and discovery learning, in conjunction with the Cognitive Load Theory, are used to evaluate the Picture Word Inductive Model (PWIM), an inquiry-oriented inductive language arts strategy designed to teach K-6 children phonics and spelling. The PWIM reflects…

  14. An Analytics-Based Approach to Managing Cognitive Load by Using Log Data of Learning Management Systems and Footprints of Social Media

    ERIC Educational Resources Information Center

    Yen, Cheng-Huang; Chen, I-Chuan; Lai, Su-Chun; Chuang, Yea-Ru

    2015-01-01

    Traces of learning behaviors generally provide insights into learners and the learning processes that they employ. In this article, a learning-analytics-based approach is proposed for managing cognitive load by adjusting the instructional strategies used in online courses. The technology-based learning environment examined in this study involved a…

  15. Exploring the Impact of Prior Knowledge and Appropriate Feedback on Students' Perceived Cognitive Load and Learning Outcomes: Animation-Based Earthquakes Instruction

    ERIC Educational Resources Information Center

    Yeh, Ting-Kuang; Tseng, Kuan-Yun; Cho, Chung-Wen; Barufaldi, James P.; Lin, Mei-Shin; Chang, Chun-Yen

    2012-01-01

    The aim of this study was to develop an animation-based curriculum and to evaluate the effectiveness of animation-based instruction; the report involved the assessment of prior knowledge and the appropriate feedback approach, for the purpose of reducing perceived cognitive load and improving learning. The curriculum was comprised of five subunits…

  16. A Case Study Examining the Impact of Cognitive Load on Reflection and Pre-Service Teachers' Transfer of Specific Teaching Behaviors

    ERIC Educational Resources Information Center

    Broyles, Thomas W.; Epler, Cory M.; Waknine, Jessica W.

    2011-01-01

    The purpose of the study was to describe the reflective experiences of pre-service teachers and determine how cognitive load impacts reflection and transfer of specific teaching behaviors. Twenty-seven Career and Technical Education pre-service teachers were randomly placed into 14 teaching teams. The teams taught a pre-written lesson which was…

  17. The effect of exercise training with an additional inspiratory load on inspiratory muscle fatigue and time-trial performance.

    PubMed

    McEntire, Serina J; Smith, Joshua R; Ferguson, Christine S; Brown, Kelly R; Kurti, Stephanie P; Harms, Craig A

    2016-08-01

    The purpose was to determine the effect of moderate-intensity exercise training (ET) on inspiratory muscle fatigue (IMF) and if an additional inspiratory load during ET (ET+IL) would further improve inspiratory muscle strength, IMF, and time-trial performance. 15 subjects were randomly divided to ET (n=8) and ET+IL groups (n=7). All subjects completed six weeks of exercise training three days/week at ∼70%V̇O2peak for 30min. The ET+IL group breathed through an inspiratory muscle trainer (15% PImax) during exercise. 5-mile, and 30-min time-trials were performed pre-training, weeks three and six. Inspiratory muscle strength increased (p<0.05) for both groups to a similar (p>0.05) extent. ET and ET+IL groups improved (p<0.05) 5-mile time-trial performance (∼10% and ∼18%) and the ET+IL group was significantly faster than ET at week 6. ET and ET+IL groups experienced less (p<0.05) IMF compared to pre-training following the 5-mile time-trial. In conclusion, these data suggest ET leads to less IMF, ET+IL improves inspiratory muscle strength and IMF, but not different than ET alone.

  18. High working memory load impairs the effect of cognitive reappraisal on emotional response: Evidence from an event-related potential study.

    PubMed

    Gan, Shuzhen; Yang, Jianfeng; Chen, Xuhai; Zhang, Xiuping; Yang, Yufang

    2017-02-03

    This study investigates how the working memory (WM) load influenced the efficacy of cognitive reappraisal, a frequently used strategy for emotion regulation. In a dual-task paradigm, the participants were required to perform a high-load or a low-load memory task and simultaneously reappraise aversive pictures with a negative or a neutral meaning. In the low-load condition, we found that the amplitude of emotion-enhanced late positive potential (LPP) was significantly decreased by neutral reappraisal compared to negative reappraisal. In the high-load condition, this regulatory effect of reappraisal disappeared. These results suggest that successful reappraisal relies on cognitive resources and WM processes. If the necessary resources involved in reappraisal are over-depleted by a concurrent memory task, the reappraisal effect will be impaired. Moreover, we found that emotion-enhanced LPP was significant in both of the high-load and low-load tasks, which suggests that emotional electrocortical response may not be susceptible to the available resources.

  19. Hydrothermally Treated Chitosan Hydrogel Loaded with Copper and Zinc Particles as a Potential Micronutrient-Based Antimicrobial Feed Additive

    PubMed Central

    Rajasekaran, Parthiban; Santra, Swadeshmukul

    2015-01-01

    Large-scale use of antibiotics in food animal farms as growth promoters is considered as one of the driving factors behind increasing incidence of microbial resistance. Several alternatives are under investigation to reduce the amount of total antibiotics used in order to avoid any potential transmission of drug resistant microbes to humans through food chain. Copper sulfate and zinc oxide salts are used as feed supplement as they exhibit antimicrobial properties in addition to being micronutrients. However, higher dosage of copper and zinc (often needed for growth promoting effect) to animals is not advisable because of potential environmental toxicity arising from excreta. Innovative strategies are needed to utilize the complete potential of trace minerals as growth promoting feed supplements. To this end, we describe here the development and preliminary characterization of hydrothermally treated chitosan as a delivery vehicle for copper and zinc nanoparticles that could act as a micronutrient-based antimicrobial feed supplement. Material characterization studies showed that hydrothermal treatment makes a chitosan hydrogel that rearranged to capture the copper and zinc metal particles. Systemic antimicrobial assays showed that this chitosan biopolymer matrix embedded with copper (57.6 μg/ml) and zinc (800 μg/ml) reduced the load of model gut bacteria (target organisms of growth promoting antibiotics), such as Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, and Lactobacillus fermentum under in vitro conditions. Particularly, the chitosan/copper/zinc hydrogel exhibited significantly higher antimicrobial effect against L. fermentum, one of the primary targets of antibiotic growth promoters. Additionally, the chitosan matrix ameliorated the cytotoxicity levels of metal supplements when screened against a murine macrophage cell line RAW 264.7 and in TE-71, a murine thymic epithelial cell line. In this proof-of-concept study, we show that by using

  20. Cognitive Load Measurements and Stimulated Recall Interviews for Studying the Effects of Information and Communications Technology

    ERIC Educational Resources Information Center

    Beers, Pieter J.; Boshuizen, Henny P. A.; Kirschner, Paul A.; Gijselaers, Wim; Westendorp, Jochem

    2008-01-01

    Many researchers use information and communications technology (ICT)-tools to augment learning in a great variety of tasks. Their effects are generally measured in terms of intended outcomes. This article argues for the use of additional, more general measures to obtain a more complete impression of the effects of ICT-tools. The first study…

  1. Measuring Cognitive Load in the Presence of Educational Video: Towards a Multimodal Methodology

    ERIC Educational Resources Information Center

    Kruger, Jan-Louis; Doherty, Stephen

    2016-01-01

    The use of video has become well established in education, from traditional courses to blended and online courses. It has grown both in its diversity of applications as well as its content. Such educational video however is not fully accessible to all students, particularly those who require additional visual support or students studying in a…

  2. Measuring cognitive load during simulation-based psychomotor skills training: sensitivity of secondary-task performance and subjective ratings.

    PubMed

    Haji, Faizal A; Khan, Rabia; Regehr, Glenn; Drake, James; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-12-01

    As interest in applying cognitive load theory (CLT) to the study and design of pedagogic and technological approaches in healthcare simulation grows, suitable measures of cognitive load (CL) are needed. Here, we report a two-phased study investigating the sensitivity of subjective ratings of mental effort (SRME) and secondary-task performance (signal detection rate, SDR and recognition reaction time, RRT) as measures of CL. In phase 1 of the study, novice learners and expert surgeons attempted a visual-monitoring task under two conditions: single-task (monitoring a virtual patient's heart-rate) and dual-task (tying surgical knots on a bench-top simulator while monitoring the virtual patient's heart-rate). Novices demonstrated higher mental effort and inferior secondary-task performance on the dual-task compared to experts (RRT 1.76 vs. 0.73, p = 0.012; SDR 0.27 vs. 0.97, p < 0.001; SRME 7.75 vs. 2.80, p < 0.001). Similarly, secondary task performance deteriorated from baseline to dual-task among novices (RRT 0.63 vs. 1.76 s, p < 0.006 and SDR 1.00 vs. 0.27, p < 0.001), but not experts (RRT 0.63 vs. 0.73 s, p = 0.124 and SDR 1.00 vs. 0.97, p = 0.178). In phase 2, novices practiced surgical knot-tying on the bench top simulator during consecutive dual-task trials. A significant increase in SDR (F(9,63) = 6.63, p < 0.001, f = 0.97) and decrease in SRME (F(9,63) = 9.39, p < 0.001, f = 1.04) was observed during simulation training, while RRT did not change significantly (F(9,63) = 1.18, p < 0.32, f = 0.41). The results suggest subjective ratings and dual-task performance can be used to track changes in CL among novices, particularly in early phases of simulation-based skills training. The implications for measuring CL in simulation instructional design research are discussed.

  3. Differential Neural Activation Patterns in Patients with Parkinson's Disease and Freezing of Gait in Response to Concurrent Cognitive and Motor Load

    PubMed Central

    Shine, James M.; Matar, Elie; Ward, Philip B.; Bolitho, Samuel J.; Pearson, Mark; Naismith, Sharon L.; Lewis, Simon J. G.

    2013-01-01

    Freezing of gait is a devastating symptom of Parkinson's disease (PD) that is exacerbated by the processing of cognitive information whilst walking. To date, no studies have explored the neural correlates associated with increases in cognitive load whilst performing a motor task in patients with freezing. In this experiment, 14 PD patients with and 15 PD patients without freezing of gait underwent 3T fMRI while performing a virtual reality gait task. Directions to walk and stop were presented on the viewing screen as either direct cues or as more cognitively indirect pre-learned cues. Both groups showed a consistent pattern of BOLD response within the Cognitive Control Network during performance of the paradigm. However, a between group comparison revealed that those PD patients with freezing of gait were less able to recruit the bilateral anterior insula, ventral striatum and the pre-supplementary motor area, as well as the left subthalamic nucleus when responding to indirect cognitive cues whilst maintaining a motor output. These results suggest that PD patients with freezing of gait are unable to properly recruit specific cortical and subcortical regions within the Cognitive Control Network during the performance of simultaneous motor and cognitive functions. PMID:23382821

  4. Delineation of the working memory profile in female FMR1 premutation carriers: the effect of cognitive load on ocular motor responses.

    PubMed

    Shelton, Annie L; Cornish, Kim M; Godler, David E; Clough, Meaghan; Kraan, Claudine; Bui, Minh; Fielding, Joanne

    2015-04-01

    Fragile X mental retardation 1 (FMR1) premutation carriers (PM-carriers) are characterised as having mid-sized expansions of between 55 and 200 CGG repeats in the 5' untranslated region of the FMR1 gene. While there is evidence of executive dysfunction in PM-carriers, few studies have explicitly explored working memory capabilities in female PM-carriers. 14 female PM-carriers and 13 age- and IQ-matched healthy controls completed an ocular motor n-back working memory paradigm. This task examined working memory ability and the effect of measured increases in cognitive load. Female PM-carriers were found to have attenuated working memory capabilities. Increasing the cognitive load did not elicit the expected reciprocal increase in the task errors for female PM-carriers, as it did in controls. However female PM-carriers took longer to respond than controls, regardless of the cognitive load. Further, FMR1 mRNA levels were found to significantly predict PM-carrier response time. Although preliminary, these findings provide further evidence of executive dysfunction, specifically disruption to working memory processes, which were found to be associated with increases in FMR1 mRNA expression in female PM-carriers. With future validation, ocular motor paradigms such as the n-back paradigm will be critical to the development of behavioural biomarkers for identification of PM-carrier cognitive-affective phenotypes.

  5. Can the Isolated-Elements Strategy Be Improved by Targeting Points of High Cognitive Load for Additional Practice?

    ERIC Educational Resources Information Center

    Ayres, Paul

    2013-01-01

    Reducing problem complexity by isolating elements has been shown to be an effective instructional strategy. Novices, in particular, benefit from learning from worked examples that contain partially interacting elements rather than worked examples that provide full interacting elements. This study investigated whether the isolating-elements…

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

    PubMed

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

    2016-03-01

    Cognitive load (CL) theory suggests that working memory can be overloaded in complex learning tasks such as surgical technical skills training, which can impair learning. Valid and feasible methods for estimating the CL in specific learning contexts are necessary before the efficacy of CL-lowering instructional interventions can be established. This study aims to explore secondary task precision for the estimation of CL in virtual reality (VR) surgical simulation and also investigate the effects of CL-modifying factors such as simulator-integrated tutoring and repeated practice. Twenty-four participants were randomized for visual assistance by a simulator-integrated tutor function during the first 5 of 12 repeated mastoidectomy procedures on a VR temporal bone simulator. Secondary task precision was found to be significantly lower during simulation compared with nonsimulation baseline, p < .001. Contrary to expectations, simulator-integrated tutoring and repeated practice did not have an impact on secondary task precision. This finding suggests that even though considerable changes in CL are reflected in secondary task precision, it lacks sensitivity. In contrast, secondary task reaction time could be more sensitive, but requires substantial postprocessing of data. Therefore, future studies on the effect of CL modifying interventions should weigh the pros and cons of the various secondary task measurements.

  7. Design of an Adaptive Human-Machine System Based on Dynamical Pattern Recognition of Cognitive Task-Load.

    PubMed

    Zhang, Jianhua; Yin, Zhong; Wang, Rubin

    2017-01-01

    This paper developed a cognitive task-load (CTL) classification algorithm and allocation strategy to sustain the optimal operator CTL levels over time in safety-critical human-machine integrated systems. An adaptive human-machine system is designed based on a non-linear dynamic CTL classifier, which maps a set of electroencephalogram (EEG) and electrocardiogram (ECG) related features to a few CTL classes. The least-squares support vector machine (LSSVM) is used as dynamic pattern classifier. A series of electrophysiological and performance data acquisition experiments were performed on seven volunteer participants under a simulated process control task environment. The participant-specific dynamic LSSVM model is constructed to classify the instantaneous CTL into five classes at each time instant. The initial feature set, comprising 56 EEG and ECG related features, is reduced to a set of 12 salient features (including 11 EEG-related features) by using the locality preserving projection (LPP) technique. An overall correct classification rate of about 80% is achieved for the 5-class CTL classification problem. Then the predicted CTL is used to adaptively allocate the number of process control tasks between operator and computer-based controller. Simulation results showed that the overall performance of the human-machine system can be improved by using the adaptive automation strategy proposed.

  8. Design of an Adaptive Human-Machine System Based on Dynamical Pattern Recognition of Cognitive Task-Load

    PubMed Central

    Zhang, Jianhua; Yin, Zhong; Wang, Rubin

    2017-01-01

    This paper developed a cognitive task-load (CTL) classification algorithm and allocation strategy to sustain the optimal operator CTL levels over time in safety-critical human-machine integrated systems. An adaptive human-machine system is designed based on a non-linear dynamic CTL classifier, which maps a set of electroencephalogram (EEG) and electrocardiogram (ECG) related features to a few CTL classes. The least-squares support vector machine (LSSVM) is used as dynamic pattern classifier. A series of electrophysiological and performance data acquisition experiments were performed on seven volunteer participants under a simulated process control task environment. The participant-specific dynamic LSSVM model is constructed to classify the instantaneous CTL into five classes at each time instant. The initial feature set, comprising 56 EEG and ECG related features, is reduced to a set of 12 salient features (including 11 EEG-related features) by using the locality preserving projection (LPP) technique. An overall correct classification rate of about 80% is achieved for the 5-class CTL classification problem. Then the predicted CTL is used to adaptively allocate the number of process control tasks between operator and computer-based controller. Simulation results showed that the overall performance of the human-machine system can be improved by using the adaptive automation strategy proposed. PMID:28367110

  9. Effects of applied stress ratio on the fatigue behavior of additively manufactured porous biomaterials under compressive loading.

    PubMed

    de Krijger, Joep; Rans, Calvin; Van Hooreweder, Brecht; Lietaert, Karel; Pouran, Behdad; Zadpoor, Amir A

    2016-12-07

    Additively manufactured (AM) porous metallic biomaterials are considered promising candidates for bone substitution. In particular, AM porous titanium can be designed to exhibit mechanical properties similar to bone. There is some experimental data available in the literature regarding the fatigue behavior of AM porous titanium, but the effect of stress ratio on the fatigue behavior of those materials has not been studied before. In this paper, we study the effect of applied stress ratio on the compression-compression fatigue behavior of selective laser melted porous titanium (Ti-6Al-4V) based on the diamond unit cell. The porous titanium biomaterial is treated as a meta-material in the context of this work, meaning that R-ratios are calculated based on the applied stresses acting on a homogenized volume. After morphological characterization using micro computed tomography and quasi-static mechanical testing, the porous structures were tested under cyclic loading using five different stress ratios, i.e. R = 0.1, 0.3, 0.5, 0.7 and 0.8, to determine their S-N curves. Feature tracking algorithms were used for full-field deformation measurements during the fatigue tests. It was observed that the S-N curves of the porous structures shift upwards as the stress ratio increases. The stress amplitude was the most important factor determining the fatigue life. Constant fatigue life diagrams were constructed and compared with similar diagrams for bulk Ti-6Al-4V. Contrary to the bulk material, there was limited dependency of the constant life diagrams to mean stress. The notches present in the AM biomaterials were the sites of crack initiation. This observation and other evidence suggest that the notches created by the AM process cause the insensitivity of the fatigue life diagrams to mean stress. Feature tracking algorithms visualized the deformation during fatigue tests and demonstrated the root cause of inclined (45°) planes of specimen failure. In conclusion, the R

  10. [Additional memory load causes changes in induced EEG beta-rhythm in experiments with a visual set formed to facial expression].

    PubMed

    Iakovenko, I A; Kozlov, M K; Cheremushkin, E A

    2012-01-01

    Subjects were divided into two equal groups 35 healthy subjects each. Formation of the visual set to facial emotion recognition was supplemented with two types of additional task: either visuospatial (to find a target stimulus among others) or verbal (to tell a word from a pseudoword). The results of the experiments were compared to those obtained in similar experiments without the memory load. Changes in the EEG beta rhythm during visual set forming and testing were studied. The EEG was analyzed by wavelet transformation. Changes in the mean level, maximum and latency of the maximum of wavelet coefficient were rated at different stages of the experiment. All these characteristics for the beta rhythm were higher in experiments with both types of additional memory load as compared to those without the memory load.

  11. Visual conflict and cognitive load modify postural responses to vibrotactile noise

    PubMed Central

    2014-01-01

    Background Underlying the increased incidence of falls during multitasking is a reduced ability to detect or attend to the sensory information signaling postural instability. Adding noise to a biological system has been shown to enhance the detection and transmission of weakened or sub-threshold cutaneous signals. If stochastic resonance is to become an effective adjunct to rehabilitation, we need to determine whether vibrotactile noise can be effective when added to an environment presenting with other sensory noise. Methods Sub-threshold vibration noise was applied for 30 sec at the soles of the feet in 21 healthy adults (20–29 yrs) between two 30-sec periods of no vibration. During the trials, subjects stood quietly with eyes closed or while viewing a visual scene that rotated in continuous upward pitch at 30 deg/sec. Subjects were also tested with these two visual conditions while performing a mental calculation task. It was hypothesized that sub-threshold vibration would increase regularity of postural sway, thereby improving postural stabilization during an attention demanding task but exerting less effect with multiple sensory demands. An ellipse fit to the covariance matrix revealed excursion of center of pressure (COP) and center of mass (COM) responses in the anterior-posterior and lateral planes. RMS values and approximate entropy of the COP and COM were calculated and statistically compared. Results The addition of vibrotactile noise to the plantar surface during quiet stance with eyes closed reduced the area of the COM and COP responses, which then returned to pre-vibration levels after vibration was removed. Postural sway was generally increased with both visual field rotations and mental calculation compared to the eyes closed condition. The effect of sub-threshold vibratory noise on postural behavior was modified when visual field rotations and mental calculation was combined. It was shown that the measure of approximate entropy reflected

  12. The impact of secondary-task type on the sensitivity of reaction-time based measurement of cognitive load for novices learning surgical skills using simulation.

    PubMed

    Rojas, David; Haji, Faizal; Shewaga, Rob; Kapralos, Bill; Dubrowski, Adam

    2014-01-01

    Interest in the measurement of cognitive load (CL) in simulation-based education has grown in recent years. In this paper we present two pilot experiments comparing the sensitivity of two reaction time based secondary task measures of CL. The results suggest that simple reaction time measures are sensitive enough to detect changes in CL experienced by novice learners in the initial stages of simulation-based surgical skills training.

  13. Cognitive load imposed by knobology may adversely affect learners' perception of utility in using ultrasonography to learn physical examination skills, but not anatomy.

    PubMed

    Jamniczky, Heather A; McLaughlin, Kevin; Kaminska, Malgorzata E; Raman, Maitreyi; Somayaji, Ranjani; Wright, Bruce; Ma, Irene W Y

    2015-01-01

    Ultrasonography is increasingly used for teaching anatomy and physical examination skills but its effect on cognitive load is unknown. This study aimed to determine ultrasound's perceived utility for learning, and to investigate the effect of cognitive load on its perceived utility. Consenting first-year medical students (n = 137) completed ultrasound training that includes a didactic component and four ultrasound-guided anatomy and physical examination teaching sessions. Learners then completed a survey on comfort with physical examination techniques (three items; alpha = 0.77), perceived utility of ultrasound in learning (two items; alpha = 0.89), and cognitive load on ultrasound use [measured with a validated nine-point scale (10 items; alpha = 0.88)]. Learners found ultrasound useful for learning for both anatomy and physical examination (mean 4.2 ± 0.9 and 4.4 ± 0.8, respectively; where 1 = very useless and 5 = very useful). Principal components analysis on the cognitive load survey revealed two factors, "image interpretation" and "basic knobology," which accounted for 60.3% of total variance. Weighted factor scores were not associated with perceived utility in learning anatomy (beta = 0.01, P = 0.62 for "image interpretation" and beta = -0.04, P = 0.33 for "basic knobology"). However, factor score on "knobology" was inversely associated with perceived utility for learning physical examination (beta = -0.06; P = 0.03). While a basic introduction to ultrasound may suffice for teaching anatomy, more training may be required for teaching physical examination. Prior to teaching physical examination skills with ultrasonography, we recommend ensuring that learners have sufficient knobology skills.

  14. Can we improve pollen season definitions by using the symptom load index in addition to pollen counts?

    PubMed

    Bastl, Katharina; Kmenta, Maximilian; Geller-Bernstein, Carmi; Berger, Uwe; Jäger, Siegfried

    2015-09-01

    Airborne pollen measurements are the foundation of aerobiological research and provide essential raw data for various disciplines. Pollen itself should be considered a relevant factor in air quality. Symptom data shed light on the relationship of pollen allergy and pollination. The aim of this study is to assess the spatial variation of local, regional and national symptom datasets. Ten pollen season definitions are used to calculate the symptom load index for the birch and grass pollen seasons (2013-2014) in Austria. (1) Local, (2) regional and (3) national symptom datasets are used to examine spatial variations and a consistent pattern was found. In conclusion, national datasets are suitable for first insights where no sufficient local or regional dataset is available and season definitions based on percentages provide a practical solution, as they can be applied in regions with different pollen loads and produce more constant results.

  15. Using Generalized Additive Modeling to Empirically Identify Thresholds within the ITERS in Relation to Toddlers' Cognitive Development

    ERIC Educational Resources Information Center

    Setodji, Claude Messan; Le, Vi-Nhuan; Schaack, Diana

    2013-01-01

    Research linking high-quality child care programs and children's cognitive development has contributed to the growing popularity of child care quality benchmarking efforts such as quality rating and improvement systems (QRIS). Consequently, there has been an increased interest in and a need for approaches to identifying thresholds, or cutpoints,…

  16. Intuition and Moral Decision-Making – The Effect of Time Pressure and Cognitive Load on Moral Judgment and Altruistic Behavior

    PubMed Central

    Bonn, Caroline; Johannesson, Magnus; Kirchler, Michael; Koppel, Lina; Västfjäll, Daniel

    2016-01-01

    Do individuals intuitively favor certain moral actions over others? This study explores the role of intuitive thinking—induced by time pressure and cognitive load—in moral judgment and behavior. We conduct experiments in three different countries (Sweden, Austria, and the United States) involving over 1,400 subjects. All subjects responded to four trolley type dilemmas and four dictator games involving different charitable causes. Decisions were made under time pressure/time delay or while experiencing cognitive load or control. Overall we find converging evidence that intuitive states do not influence moral decisions. Neither time-pressure nor cognitive load had any effect on moral judgments or altruistic behavior. Thus we find no supporting evidence for the claim that intuitive moral judgments and dictator game giving differ from more reflectively taken decisions. Across all samples and decision tasks men were more likely to make utilitarian moral judgments and act selfishly compared to women, providing further evidence that there are robust gender differences in moral decision-making. However, there were no significant interactions between gender and the treatment manipulations of intuitive versus reflective decision-making. PMID:27783704

  17. Evaluation of five additional enhancements to the building loads analysis and system thermodynamics (BLAST) program. Final report

    SciTech Connect

    Nemeth, R.J.

    1993-04-01

    The Building Loads Analysis and System Thermodynamics (BLAST) energy analysis computer program has undergone a multiyear enhancement program based on feedback and priorities of the BLAST users' group. This project was conducted to evaluate the convenience and applicability of the following BLAST enhancements: Air-to-Air Heat Pump; Expanded Baseboard Heat Options; Report Writer; Thermal Comfort Model. Ice Storage Model; Evaluation responses indicate that the enhancements satisfied users' needs for advanced building energy analysis tools. Although the evaluations revealed program bugs and the lack of documentation in some areas, the programs were easy to install and use. The bugs have been removed and the documentation expanded in the BLAST Users Reference. It is recommended that the enhancements be distributed with future updates and releases of the BLAST program.... BLAST, Enhancements, Energy efficient, Comfort analysis, Technology Transfer Test Bed(T3B).

  18. Investigating the influence of working memory capacity when driving behavior is combined with cognitive load: An LCT study of young novice drivers.

    PubMed

    Ross, Veerle; Jongen, Ellen M M; Wang, Weixin; Brijs, Tom; Brijs, Kris; Ruiter, Robert A C; Wets, Geert

    2014-01-01

    Distracted driving has received increasing attention in the literature due to potential adverse safety outcomes. An often posed solution to alleviate distraction while driving is hands-free technology. Interference by distraction can occur however at the sensory input (e.g., visual) level, but also at the cognitive level where hands-free technology induces working memory (WM) load. Active maintenance of goal-directed behavior in the presence of distraction depends on WM capacity (i.e., Lavie's Load theory) which implies that people with higher WM capacity are less susceptible to distractor interference. This study investigated the interaction between verbal WM load and WM capacity on driving performance to determine whether individuals with higher WM capacity were less affected by verbal WM load, leading to a smaller deterioration of driving performance. Driving performance of 46 young novice drivers (17-25 years-old) was measured with the lane change task (LCT). Participants drove without and with verbal WM load of increasing complexity (auditory-verbal response N-back task). Both visuospatial and verbal WM capacity were investigated. Dependent measures were mean deviation in the lane change path (MDEV), lane change initiation (LCI) and percentage of correct lane changes (PCL). Driving experience was included as a covariate. Performance on each dependent measure deteriorated with increasing verbal WM load. Meanwhile, higher WM capacity related to better LCT performance. Finally, for LCI and PCL, participants with higher verbal WM capacity were influenced less by verbal WM load. These findings entail that completely eliminating distraction is necessary to minimize crash risks among young novice drivers.

  19. Distinctive activation patterns under intrinsically versus extrinsically driven cognitive loads in prefrontal cortex: a near-infrared spectroscopy study using a driving video game.

    PubMed

    Liu, Tao; Saito, Hirofumi; Oi, Misato

    2012-01-11

    To investigate the neural bases of intrinsically and extrinsically driven cognitive loads in daily life, we measured repetitively prefrontal activation in three (one control and two experimental) groups during a driving video game using near-infrared spectroscopy. The control group drove to goal four times with distinct route-maps illustrating default turning points. In contrast, the memory group drove the memorized default route without a route-map, and the emergency group drove with a route-map, but was instructed to change the default route by an extrinsically given verbal command (turn left or right) as an envisioned emergency. The predictability of a turning point in the route in each group was relatively different: due to extrinsic dictate of others in the emergency group, intrinsic memory in the memory group, and route-map aid in the control group. We analyzed concentration changes of oxygenated hemoglobin (CoxyHb) in the three critical periods (pre-turning, actual-turning, and post-turning). The emergency group showed a significantly increasing pattern of CoxyHb throughout the three periods, and a significant reduction in CoxyHb throughout the repetitive trials, but the memory group did not, even though both experimental groups showed higher activation than the control group in the pre-turning period. These results suggest that the prefrontal cortex differentiates the intrinsically (memory) and the extrinsically (dictate of others) driven cognitive loads according to the predictability of turning behavior, although the two types of cognitive loads commonly show increasing activation in the pre-turning period as the preparation effect.

  20. Lack of confidence in the lower limb: Cognitive Functional Therapy (CFT) for a unilateral loading impairment in chronic non-specific low back pain. Case report.

    PubMed

    Meziat Filho, Ney; Mendonça, Roberta; Nogueira, Leandro Alberto Calazans

    2016-09-01

    This case report presents the effect of Cognitive Functional Therapy (CFT) in a patient with chronic non-specific low back pain associated with unilateral loading impairment of the left lower limb. The patient believed surgery was the only possible way to treat the cause of the problem. The management of this idea was to change such belief. Manual therapy and active exercises were combined in order to encourage the patient to trust his back and lower limb again. One month and a half after the first appointment, the treatment resulted in complete absence of pain and disability. The patient returned to work and he was able to climb stairs and load his left limb normally.

  1. Calcium nitrate addition to control the internal load of phosphorus from sediments of a tropical eutrophic reservoir: microcosm experiments.

    PubMed

    Yamada, T M; Sueitt, A P E; Beraldo, D A S; Botta, C M R; Fadini, P S; Nascimento, M R L; Faria, B M; Mozeto, A A

    2012-12-01

    The main objective of this study was to perform laboratory experiments on calcium nitrate addition to sediments of a tropical eutrophic urban reservoir (Ibirité reservoir, SE Brazil) to immobilize the reactive soluble phosphorus (RSP) and to evaluate possible geochemical changes and toxic effects caused by this treatment. Reductions of 75 and 89% in the concentration of RSP were observed in the water column and interstitial water, respectively, after 145 days of nitrate addition. The nitrate application increased the rate of autotrophic denitrification, causing a consumption of 98% of the added nitrate and oxidation of 99% of the acid volatile sulfide. As a consequence, there were increases in the sulfate and iron (II) concentrations in the sediment interstitial water and water column, as well as changes in the copper speciation in the sediments. Toxicity tests initially indicated that the high concentrations of nitrate and nitrite in the sediment interstitial water (up to 2300 mg L(-1) and 260 mg L(-1), respectively) were the major cause of mortality of Ceriodaphnia silvestrii and Chironomus xanthus. However, at the end of the experiment, the sediment toxicity was completely removed and a reduction in the 48 h-EC50 of the water was also observed. Based on these results we can say that calcium nitrate treatment proved to be a valuable tool in remediation of eutrophic aquatic ecosystems leading to conditions that can support a great diversity of organisms after a restoration period.

  2. Cardiovascular and respiratory correlates of deep nociceptive stimulation, suggestions for analgesia, pain imagery and cognitive load as a function of hypnotizability.

    PubMed

    Paoletti, Giulia; Varanini, Maurizio; Balocchi, Rita; Morizzo, Carmela; Palombo, Carlo; Santarcangelo, Enrica L

    2010-04-29

    Hypnotizability is a cognitive trait modulating some physiological responses to cognitive and physical stimulation also in the normal awake state and in the absence of specific suggestions. Aim of the study was the characterization of the cardiovascular correlates of deep pain induced by nociceptive pressor stimulation without (PAIN) and with (AN) suggestions for analgesia, pain imagery/perception (IM) and mental computation (MC) in not hypnotized highly (Highs) and low (Lows) hypnotizable healthy subjects of both genders. The subjective experience of pain intensity, relaxation and task related fatigue were measured through a structured interview. Heart rate, blood pressure, skin blood flow and respiratory activity were monitored throughout the experimental session. Only Highs perceived lower pain intensity during AN with respect to PAIN and were able to perceive pain during IM. Heart rate decreased during PAIN, increased during MC and did not change during AN and IM in both groups. On the whole, the haemodynamic response consisted of decreased systolic/mean blood pressure and maximum skin blood flow together with increased diastolic blood pressure/minimum skin blood flow in both groups during all conditions. Scarce differences were observed between Highs and Lows (in systolic blood pressure during IM and in respiratory amplitude during PAIN, AN and IM, modulated by gender). The results indicate that in not hypnotized subjects hypnotizability is not associated with relevant differences in the autonomic responses to deep pain, suggestions for analgesia, pain imagery/perception and cognitive load.

  3. Applying Social Tagging to Manage Cognitive Load in a Web 2.0 Self-Learning Environment

    ERIC Educational Resources Information Center

    Huang, Yueh-Min; Huang, Yong-Ming; Liu, Chien-Hung; Tsai, Chin-Chung

    2013-01-01

    Web-based self-learning (WBSL) has received a lot of attention in recent years due to the vast amount of varied materials available in the Web 2.0 environment. However, this large amount of material also has resulted in a serious problem of cognitive overload that degrades the efficacy of learning. In this study, an information graphics method is…

  4. Towards the Use of a Novel Method: The First Experiences on Measuring the Cognitive Load of Learned Programming Skills

    ERIC Educational Resources Information Center

    Uysal, Murat Pasa

    2013-01-01

    Teaching object-oriented programming (OOP) is a difficult task, especially to the beginners. First-time learners also find it difficult to understand. Although there is a considerable amount of study on the cognitive dimension, a few study points out its physiological meaning. Moreover, it has been suggested that neuroscientific studies and…

  5. The effect of beverages varying in glycaemic load on postprandial glucose responses, appetite and cognition in 10-12-year-old school children.

    PubMed

    Brindal, Emily; Baird, Danielle; Slater, Amy; Danthiir, Vanessa; Wilson, Carlene; Bowen, Jane; Noakes, Manny

    2013-08-28

    Reducing glycaemic index (GI) and glycaemic load (GL) inconsistently improves aspects of cognitive function and appetite in children. Whether altering the GL by lowering carbohydrate relative to protein and fat has a role in these effects is unknown. Therefore, we assessed the differential effects of beverages varying in GL and dairy composition on appetite, energy intake and cognitive function in children. A total of forty children (10–12 years) completed a double-blind, randomised, crossover trial, receiving three isoenergetic drinks (approximately 1100 kJ): a glucose beverage (GI 100, GL 65), a full milk beverage (GI 27, GL 5) and a half milk/glucose beverage (GI 84, GL 35). For 3 h post-consumption, subjective appetite and cognitive performance (speed of processing, memory, attention and perceptual speed) were measured hourly. At completion, each child was provided a buffet-style lunch and energy intake was calculated. Blood glucose was objectively measured using the Continuous Glucose Monitoring System. Blood glucose AUC values were significantly different between the drinks (P,0·001), but did not sustain above the baseline for 3 h for any drink. Mixed modelling revealed no effect of beverage on subjective appetite or energy intake. Participant sex and drink GL significantly interacted for short-term memory (P,0·001). When girls consumed either milk-containing beverage, they recalled 0·7–0·8 more words compared with 0·5 less words after the glucose drink (P#0·014). Altering GL of drinks by reducing carbohydrate and increasing protein did not affect appetite or cognition in children. Girls may demonstrate improved short-term memory after consuming beverages with higher protein and lower GL.

  6. Controlled flame synthesis of αFe2O3 and Fe3O4 nanoparticles: effect of flame configuration, flame temperature, and additive loading

    NASA Astrophysics Data System (ADS)

    Buyukhatipoglu, K.; Morss Clyne, A.

    2010-05-01

    Superparamagnetic iron oxide nanoparticles are used in diverse applications, including optical magnetic recording, catalysts, gas sensors, targeted drug delivery, magnetic resonance imaging, and hyperthermic malignant cell therapy. Combustion synthesis of nanoparticles has significant advantages, including improved nanoparticle property control and commercial production rate capability with minimal post-processing. In the current study, superparamagnetic iron oxide nanoparticles were produced by flame synthesis using a coflow flame. The effect of flame configuration (diffusion and inverse diffusion), flame temperature, and additive loading on the final iron oxide nanoparticle morphology, elemental composition, and particle size were analyzed by transmission electron microscopy (TEM), high-resolution TEM (HR-TEM), energy dispersive spectroscopy (EDS), and Raman spectroscopy. The synthesized nanoparticles were primarily composed of two well known forms of iron oxide, namely hematite αFe2O3 and magnetite Fe3O4. We found that the synthesized nanoparticles were smaller (6-12 nm) for an inverse diffusion flame as compared to a diffusion flame configuration (50-60 nm) when CH4, O2, Ar, and N2 gas flow rates were kept constant. In order to investigate the effect of flame temperature, CH4, O2, Ar gas flow rates were kept constant, and N2 gas was added as a coolant to the system. TEM analysis of iron oxide nanoparticles synthesized using an inverse diffusion flame configuration with N2 cooling demonstrated that particles no larger than 50-60 nm in diameter can be grown, indicating that nanoparticles did not coalesce in the cooler flame. Raman spectroscopy showed that these nanoparticles were primarily magnetite, as opposed to the primarily hematite nanoparticles produced in the hot flame configuration. In order to understand the effect of additive loading on iron oxide nanoparticle morphology, an Ar stream carrying titanium-tetra-isopropoxide (TTIP) was flowed through the

  7. Tracking object number or information load in visual working memory: revisiting the cognitive implication of contralateral delay activity.

    PubMed

    Gao, Zaifeng; Yin, Jun; Xu, Haokui; Shui, Rende; Shen, Mowei

    2011-05-01

    Two accounts prevail for the ERP component contralateral delay activity (CDA). One is that CDA tracks the number of objects stored in visual working memory (VWM), the more objects the higher amplitude (object number account). The other is that CDA reflects the maintained information load (information load account), the higher load the higher amplitude. The two accounts were tested by manipulating the information load and the object number of stored objects. Two or four arrows with low- or high-resolution information were remembered in separate blocks. In two experiments we found that the CDA-amplitude was higher for 4 arrows than for 2 arrows in low-resolution condition, yet no difference in high-resolution condition. Critically, there was no difference on CDA-amplitude among 2 low- and high-resolution objects, as well as 4 high-resolution objects, yet all were significantly lower than 4 low-resolution arrows. These results supported the object number account of CDA.

  8. The effects of cognitive load during intertrial intervals on judgements of control: The role of working memory and contextual learning.

    PubMed

    Cavus, H A; Msetfi, Rachel M

    2016-11-01

    When there is no contingency between actions and outcomes, but outcomes occur frequently, people tend to judge that they have control over those outcomes, a phenomenon known as the outcome density (OD) effect. Recent studies show that the OD effect depends on the duration of the temporal interval between action-outcome conjunctions, with longer intervals inducing stronger effects. However, under some circumstances OD effect is reduced, for example when participants are mildly depressed. We reasoned that working memory (WM) plays an important role in learning of context; with reduced WM capacity to process contextual information during intertrial intervals (ITIs) during contingency learning might lead to reduced OD effects (limited capacity hypothesis). To test this, we used a novel dual-task procedure that increases the WM load during the ITIs of an operant (e.g., action-outcome) contingency learning task to impact contextual learning. We tested our hypotheses in groups of students with zero (Experiments 1, N=34), and positive contingencies (Experiment 2, N=34). The findings indicated that WM load during the ITIs reduced the OD effects compared to no load conditions (Experiment 1 and 2). In Experiment 2, we observed reduced OD effects on action judgements under high load in zero and positive contingencies. However, the participants' judgements were still sensitive to the difference between zero and positive contingencies. We discuss the implications of our findings for the effects of depression and context in contingency learning.

  9. Additional cooling and heating load improvements in seasonal performance modeling of room and central air conditioners and heat pumps. Topical report, Subtask 3. 2

    SciTech Connect

    Not Available

    1980-04-09

    The study focuses on improving the load modeling technique of Seasonal Performance Model (SPM) in order to estimate a more realistic load for seasonal analysis calculations on an hourly basis. A computer simulation program, Seasonal Performance Model Load (SPMLD), was used to calculate the cooling and heating loads for a typical residence in Caribou, Maine; Columbia, Missouri; and Fort Worth, Texas. The derivation of the SPMLD is described and changes made to improve cooling and heating load estimates are identified. (MCW)

  10. The central nervous system--an additional consideration in 'rotator cuff tendinopathy' and a potential basis for understanding response to loaded therapeutic exercise.

    PubMed

    Littlewood, Chris; Malliaras, Peter; Bateman, Marcus; Stace, Richmond; May, Stephen; Walters, Stephen

    2013-12-01

    Tendinopathy is a term used to describe a painful tendon disorder but despite being a well-recognised clinical presentation, a definitive understanding of the pathoaetiology of rotator cuff tendinopathy remains elusive. Current explanatory models, which relate to peripherally driven nocioceptive mechanisms secondary to structural abnormality, or failed healing, appear inadequate on their own in the context of current literature. In light of these limitations this paper presents an extension to current models that incorporates the integral role of the central nervous system in the pain experience. The role of the central nervous system (CNS) is described and justified along with a potential rationale to explain the favourable response to loaded therapeutic exercises demonstrated by previous studies. This additional consideration has the potential to offer a useful way to explain pain to patients, for clinicians to prescribe appropriate therapeutic management strategies and for researchers to advance knowledge in relation to this clinically challenging problem.

  11. Pretreatment of Asian elephant (Elephas maximus) spermatozoa with cholesterol-loaded cyclodextrins and glycerol addition at 4°C improves cryosurvival.

    PubMed

    Kiso, Wendy K; Asano, Atsushi; Travis, Alexander J; Schmitt, Dennis L; Brown, Janine L; Pukazhenthi, Budhan S

    2012-01-01

    Asian elephant spermatozoa are sensitive to chilling and do not respond well to cryopreservation. The objectives of the present study were to: (1) determine whether cholesterol content can be modified by preincubation of Asian elephant spermatozoa with cholesterol-loaded cyclodextrin (CLC); and (2) assess the effects of CLC concentration(s), temperature at time of glycerol addition (22°C vs 4°C) and dilution medium on post-thaw sperm survival. Spermatozoa incubated with ≥1.5 mg CLC exhibited increased (P < 0.05) cholesterol concentrations. Pretreatment of spermatozoa with 1.5 mg CLC resulted in improvements (P < 0.05) in all post-thaw parameters. Glycerol addition at 4°C also improved all post-thaw parameters compared with 22°C. Dilution of thawed spermatozoa in an egg yolk-based medium improved (P < 0.05) motility compared with Ham's F-10 culture medium. In summary, our findings indicate that modifying cholesterol content within the plasma membrane improves the cryosurvival of Asian elephant spermatozoa. The development of an improved cryopreservation method that includes modification of membrane cholesterol and the addition of glycerol at 4°C, as reported in the present study, is an important step towards utilisation of cryopreserved spermatozoa in captive management of this species.

  12. Identifying patients with poststroke mild cognitive impairment by pattern recognition of working memory load-related ERP.

    PubMed

    Li, Xiaoou; Yan, Yuning; Wei, Wenshi

    2013-01-01

    The early detection of subjects with probable cognitive deficits is crucial for effective appliance of treatment strategies. This paper explored a methodology used to discriminate between evoked related potential signals of stroke patients and their matched control subjects in a visual working memory paradigm. The proposed algorithm, which combined independent component analysis and orthogonal empirical mode decomposition, was applied to extract independent sources. Four types of target stimulus features including P300 peak latency, P300 peak amplitude, root mean square, and theta frequency band power were chosen. Evolutionary multiple kernel support vector machine (EMK-SVM) based on genetic programming was investigated to classify stroke patients and healthy controls. Based on 5-fold cross-validation runs, EMK-SVM provided better classification performance compared with other state-of-the-art algorithms. Comparing stroke patients with healthy controls using the proposed algorithm, we achieved the maximum classification accuracies of 91.76% and 82.23% for 0-back and 1-back tasks, respectively. Overall, the experimental results showed that the proposed method was effective. The approach in this study may eventually lead to a reliable tool for identifying suitable brain impairment candidates and assessing cognitive function.

  13. Methadone dosage and its relationship to quality of life, satisfaction, psychopathology, cognitive performance and additional consumption of non-prescribed drugs.

    PubMed

    Pedrero-Pérez, Eduardo J; MethaQoL, Grupo

    2016-06-14

    The effectiveness of methadone maintenance treatment is beyond any doubt, but there remains some incertitude about the appropriate and effective dosage and the objectives that should be achieved by this therapy. Some authors maintain that only doses higher than 50-60 mg/day ought to be considered effective, since only these block all the opioid receptors. But others propose the use of doses adjusted to the needs of the patient, based on their recovery process. Quality of life, satisfaction with treatment, psychopathological symptoms, cognitive performance and additional intake of illegal and unprescribed drugs were evaluated in a representative sample of all patients treated with opioid agonists in the Addiction Institute of Madrid (N = 1898, n = 450) and the Junta de Extremadura (N = 100, n = 65). The results revealed a negative relationship between dose and quality of life, psychopathological symptoms and cognitive performance. Satisfaction with treatment, based on doses negotiated together by doctor and patient, was very high, regardless of the dose. To establish hypothetical causal dependencies among the studied variables structural equation modelling was performed. The results reject the need for high dosage if not required by the patient, and highlight the benefits of other psychosocial interventions that lead to recovery, despite the chronification that could imply the use of high doses. Whereas high dosage programmes provide better indicators of social control, the patient's quality of life must be one of the main indicators of a successful treatment, as in any other health problem.

  14. Cognitive and affective empathy in children with conduct problems: additive and interactive effects of callous-unemotional traits and autism spectrum disorders symptoms.

    PubMed

    Pasalich, Dave S; Dadds, Mark R; Hawes, David J

    2014-11-30

    Callous-unemotional (CU) traits and autism spectrum disorders (ASD) symptoms are characterized by problems in empathy; however, these behavioral features are rarely examined together in children with conduct problems. This study investigated additive and interactive effects of CU traits and ASD symptoms in relation to cognitive and affective empathy in a non-ASD clinic-referred sample. Participants were 134 children aged 3 to 9 years (M=5.60; 79% boys) with oppositional defiant/conduct disorder, and their parents. Clinicians, teachers, and parents reported on dimensions of child behavior, and parental reports of family dysfunction and direct observations of parental warmth/responsiveness assessed quality of family relationships. Results from multiple regression analysis showed that, over and above the effects of child conduct problem severity and quality of family relationships, both ASD symptoms and CU traits were uniquely associated with deficits in cognitive empathy. Moreover, CU traits demonstrated an independent association with affective empathy, and this relationship was moderated by ASD symptoms. That is, there was a stronger negative association between CU traits and affective empathy at higher versus lower levels of ASD symptoms. These findings suggest including both CU traits and ASD-related social impairments in models delineating the atypical development of empathy in children with conduct problems.

  15. Effect of a fullerene C60 addition on the strength properties of nanocrystalline copper and aluminum under shock-wave loading

    NASA Astrophysics Data System (ADS)

    Bezruchko, G. S.; Razorenov, S. V.; Popov, M. Yu.

    2014-03-01

    The Hugoniot elastic limit and the spall strength of aluminum and copper samples pressed from a mixture of a metallic powder and 2-5 wt % C60 fullerene powder are measured under a shock loading pressure up to 6 GPa and a strain rate of 105 s-1 by recording and analyzing full wave profiles using a VISAR laser interferometer. It is shown that a 5% C60 fullerene addition to an initial aluminum sample leads to an increase in its Hugoniot elastic limit by an order of magnitude. Mixture copper samples with 2% fullerene also exhibit a multiple increase in the elastic limit as compared to commercial-grade copper. The elastic limits calculated from the wave profiles are 0.82-1.56 GPa for aluminum samples and 1.35-3.46 GPa for copper samples depending on the sample porosity. The spall strength of both aluminum and copper samples with fullerene additions decreases approximately threefold because of the effect of high-hardness fullerene particles, which serve as tensile stress concentrators in a material under dynamic fracture.

  16. Are Providers More Likely to Contribute to Healthcare Disparities Under High Levels of Cognitive Load? How Features of the Healthcare Setting May Lead to Biases in Medical Decision Making

    PubMed Central

    Burgess, Diana J.

    2014-01-01

    Systematic reviews of healthcare disparities suggest that clinicians’ diagnostic and therapeutic decision making varies by clinically irrelevant characteristics, such as patient race, and that this variation may contribute to healthcare disparities. However, there is little understanding of the particular features of the healthcare setting under which clinicians are most likely to be inappropriately influenced by these characteristics. This study delineates several hypotheses to stimulate future research in this area. It is posited that healthcare settings in which providers experience high levels of cognitive load will increase the likelihood of racial disparities via 2 pathways. First, providers who experience higher levels of cognitive load are hypothesized to make poorer medical decisions and provide poorer care for all patients, due to lower levels of controlled processing (H1). Second, under greater levels of cognitive load, it is hypothesized that healthcare providers’ medical decisions and interpersonal behaviors will be more likely to be influenced by racial stereotypes, leading to poorer processes and outcomes of care for racial minority patients (H2). It is further hypothesized that certain characteristics of healthcare settings will result in higher levels of cognitive load experienced by providers (H3). Finally, it is hypothesized that minority patients will be disproportionately likely to be treated in healthcare settings in which providers experience greater levels of cognitive load (H4a), which will result in racial disparities due to lower levels of controlled processing by providers (H4b) and the influence of racial stereotypes (H4c).The study concludes with implications for research and practice that flow from this framework. PMID:19726783

  17. Cognitive Functioning and Heat Strain: Performance Responses and Protective Strategies.

    PubMed

    Schmit, Cyril; Hausswirth, Christophe; Le Meur, Yann; Duffield, Rob

    2016-12-17

    Despite the predominance of research on physical performance in the heat, many activities require high cognitive functioning for optimal performance (i.e. decision making) and/or health purposes (i.e. injury risk). Prolonged periods of demanding cognitive activity or exercise-induced fatigue will incur altered cognitive functioning. The addition of hot environmental conditions will exacerbate poor cognitive functioning and negatively affect performance outcomes. The present paper attempts to extract consistent themes from the heat-cognition literature to explore cognitive performance as a function of the level of heat stress encountered. More specifically, experimental studies investigating cognitive performance in conditions of hyperthermia, often via the completion of computerised tasks (i.e. cognitive tests), are used to better understand the relationship between endogenous thermal load and cognitive performance. The existence of an inverted U-shaped relationship between hyperthermia development and cognitive performance is suggested, and highlights core temperatures of ~38.5 °C as the potential 'threshold' for hyperthermia-induced negative cognitive performance. From this perspective, interventions to slow or blunt thermal loads and protect both task- and hyperthermia-related changes in task performances (e.g. cooling strategies) could be used to great benefit and potentially preserve cognitive performance during heat strain.

  18. Male mice housed in groups engage in frequent fighting and show a lower response to additional bone loading than females or individually housed males that do not fight.

    PubMed

    Meakin, Lee B; Sugiyama, Toshihiro; Galea, Gabriel L; Browne, William J; Lanyon, Lance E; Price, Joanna S

    2013-05-01

    Experiments to investigate bone's physiological adaptation to mechanical loading frequently employ models that apply dynamic loads to bones in vivo and assess the changes in mass and architecture that result. It is axiomatic that bones will only show an adaptive response if the applied artificial loading environment differs in a significant way from that to which the bones have been habituated by normal functional loading. It is generally assumed that this normal loading is similar between experimental groups. In the study reported here we found that this was not always the case. Male and female 17-week-old C57BL/6 mice were housed in groups of six, and a single episode (40 cycles) of non-invasive axial loading, engendering 2,200 με on the medial surface of the proximal tibiae in sample mice, was applied to right tibiae on alternate days for two weeks. This engendered an adaptive increase in bone mass in females, but not males. Observation revealed the main difference in behaviour between males and females was that males were involved in fights 1.3 times per hour, whereas the females never fought. We therefore housed all mice individually. In females, there was a similar significant osteogenic response to loading in cortical and trabecular bone of both grouped and individual mice. In contrast, in males, adaptive increases in the loaded compared with non-loaded control bones was only apparent in animals housed individually. Our interpretation of these findings is that the frequent vigorous fighting that occurs between young adult males housed in groups could be sufficient to engender peak strains and strain rates that equal or exceed the stimulus derived from artificial loading. This indicates the importance of ensuring that physical activity is consistent between groups. Reducing the background level of the naturally engendered strain environment allows adaptive responses to artificial loading to be demonstrated at lower loads.

  19. Replication of a gene-environment interaction Via Multimodel inference: additive-genetic variance in adolescents' general cognitive ability increases with family-of-origin socioeconomic status.

    PubMed

    Kirkpatrick, Robert M; McGue, Matt; Iacono, William G

    2015-03-01

    The present study of general cognitive ability attempts to replicate and extend previous investigations of a biometric moderator, family-of-origin socioeconomic status (SES), in a sample of 2,494 pairs of adolescent twins, non-twin biological siblings, and adoptive siblings assessed with individually administered IQ tests. We hypothesized that SES would covary positively with additive-genetic variance and negatively with shared-environmental variance. Important potential confounds unaddressed in some past studies, such as twin-specific effects, assortative mating, and differential heritability by trait level, were found to be negligible. In our main analysis, we compared models by their sample-size corrected AIC, and base our statistical inference on model-averaged point estimates and standard errors. Additive-genetic variance increased with SES-an effect that was statistically significant and robust to model specification. We found no evidence that SES moderated shared-environmental influence. We attempt to explain the inconsistent replication record of these effects, and provide suggestions for future research.

  20. Replication of a Gene-Environment Interaction via Multimodel Inference: Additive-Genetic Variance in Adolescents’ General Cognitive Ability Increases with Family-of-Origin Socioeconomic Status

    PubMed Central

    Kirkpatrick, Robert M.; McGue, Matt; Iacono, William G.

    2015-01-01

    The present study of general cognitive ability attempts to replicate and extend previous investigations of a biometric moderator, family-of-origin socioeconomic status (SES), in a sample of 2,494 pairs of adolescent twins, non-twin biological siblings, and adoptive siblings assessed with individually administered IQ tests. We hypothesized that SES would covary positively with additive-genetic variance and negatively with shared-environmental variance. Important potential confounds unaddressed in some past studies, such as twin-specific effects, assortative mating, and differential heritability by trait level, were found to be negligible. In our main analysis, we compared models by their sample-size corrected AIC, and base our statistical inference on model-averaged point estimates and standard errors. Additive-genetic variance increased with SES—an effect that was statistically significant and robust to model specification. We found no evidence that SES moderated shared-environmental influence. We attempt to explain the inconsistent replication record of these effects, and provide suggestions for future research. PMID:25539975

  1. Enhanced osteogenic activity and anti-inflammatory properties of Lenti-BMP-2-loaded TiO2 nanotube layers fabricated by lyophilization following trehalose addition

    PubMed Central

    Zhang, Xiaochen; Zhang, Zhiyuan; Shen, Gang; Zhao, Jun

    2016-01-01

    To enhance biocompatibility and osseointegration between titanium implants and surrounding bone tissue, numerous efforts have been made to modify the surface topography and composition of Ti implants. In this paper, Lenti-BMP-2-loaded TiO2 nanotube coatings were fabricated by lyophilization in the presence of trehalose to functionalize the surface. We characterized TiO2 nanotube layers in terms of the following: surface morphology; Lenti-BMP-2 and trehalose release; their ability to induce osteogenesis, proliferation, and anti-inflammation in vitro; and osseointegration in vivo. The anodized TiO2 nanotube surfaces exhibited an amorphous glassy matrix perpendicular to the Ti surface. Both Lenti-BMP-2 and trehalose showed sustained release over the course of 8 days. Results from real-time quantitative polymerase chain reaction studies demonstrated that lyophilized Lenti-BMP-2/TiO2 nanotubes constructed with trehalose (Lyo-Tre-Lenti-BMP-2) significantly promoted osteogenic differentiation of bone marrow stromal cells but not their proliferation. In addition, Lyo-Tre-Lenti-BMP-2 nanotubes effectively inhibited lipopolysaccharide-induced interleukin-1β and tumor necrosis factor-α production. In vivo, the formulation also promoted osseointegration. This study presents a promising new method for surface-modifying biomedical Ti-based implants to simultaneously enhance their osteogenic potential and anti-inflammatory properties, which can better satisfy clinical needs. PMID:26869786

  2. Cognitive Achievement and Motivation in Hands-on and Teacher-Centred Science Classes: Does an additional hands-on consolidation phase (concept mapping) optimise cognitive learning at work stations?

    NASA Astrophysics Data System (ADS)

    Gerstner, Sabine; Bogner, Franz X.

    2010-05-01

    Our study monitored the cognitive and motivational effects within different educational instruction schemes: On the one hand, teacher-centred versus hands-on instruction; on the other hand, hands-on instruction with and without a knowledge consolidation phase (concept mapping). All the instructions dealt with the same content. For all participants, the hands-on approach as well as the concept mapping adaptation were totally new. Our hands-on approach followed instruction based on "learning at work stations". A total of 397 high-achieving fifth graders participated in our study. We used a pre-test, post-test, retention test design both to detect students' short-term learning success and long-term learning success, and to document their decrease rates of newly acquired knowledge. Additionally, we monitored intrinsic motivation. Although the teacher-centred approach provided higher short-term learning success, hands-on instruction resulted in relatively lower decrease rates. However, after six weeks, all students reached similar levels of newly acquired knowledge. Nevertheless, concept mapping as a knowledge consolidation phase positively affected short-term increase in knowledge. Regularly placed in instruction, it might increase long-term retention rates. Scores of interest, perceived competence and perceived choice were very high in all the instructional schemes.

  3. The cognitive benefits of movement reduction: evidence from dance marking.

    PubMed

    Warburton, Edward C; Wilson, Margaret; Lynch, Molly; Cuykendall, Shannon

    2013-09-01

    In a number of domains, humans adopt a strategy of systematically reducing and minimizing a codified system of movement. One particularly interesting case is "marking" in dance, wherein the dancer performs an attenuated version of the choreography during rehearsal. This is ostensibly to save the dancer's physical energy, but a number of considerations suggest that it may serve a cognitive function as well. In this study, we tested this embodied-cognitive-load hypothesis by manipulating whether dancers rehearsed by marking or by dancing "full out" and found that performance was superior in the dancers who had marked. This finding indicates that marking confers cognitive benefits during the rehearsal process, and it raises questions regarding the cognitive functions of other movement-reduction systems, such as whispering, gesturing, and subvocalizing. In addition, it has implications for a variety of topics in cognitive science, including embodied cognition and the nascent fields of dance and music cognition.

  4. Psychosocial Working Conditions and Cognitive Complaints among Swedish Employees

    PubMed Central

    Stenfors, Cecilia U. D.; Magnusson Hanson, Linda; Oxenstierna, Gabriel; Theorell, Töres; Nilsson, Lars-Göran

    2013-01-01

    Background Cognitive complaints involving problems with concentration, memory, decision-making and thinking are relatively common in the work force. The sensitivity of both subjective and objective cognitive functioning to common psychiatric conditions, stress levels and to cognitive load makes it plausible that psychosocial working conditions play a role in cognitive complaints. Thus, this study aimed to test the associations between psychosocial work factors and cognitive complaints in nationally representative samples of the Swedish work force. Cross-sectional (n = 9751) and prospective (n = 3644; two time points two years apart) sequential multiple regression analyses were run, adjusting for general confounders, depressive- and sleeping problems. Additional prospective analyses were run adjusting for baseline cognitive complaints. Cross-sectional results High quantitative demands, information and communication technology (ICT) demands, underqualification and conflicts were positively associated with cognitive complaints, while social support, good resources at work and overqualification were negatively associated with cognitive complaints in all models. Skill discretion and decision authority were weakly associated with cognitive complaints. Conflicts were more strongly associated with cognitive complaints in women than in men, after adjustment for general confounders. Prospective results Quantitative job demands, ICT demands and underqualification were positively associated with future cognitive complaints in all models, including when adjusted for baseline cognitive complaints. Decision authority was weakly positively associated with future cognitive complaints, only after adjustment for depressive- and sleeping problems respectively. Social support was negatively associated with future cognitive complaints after adjustment for general confounders and baseline cognitive complaints. Skill discretion and resources were negatively associated with future

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

    PubMed

    Galy, Edith; Mélan, Claudine

    2015-12-01

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

  6. Cognitive context detection using pupillary measurements

    NASA Astrophysics Data System (ADS)

    Mannaru, Pujitha; Balasingam, Balakumar; Pattipati, Krishna; Sibley, Ciara; Coyne, Joseph

    2016-05-01

    In this paper, we demonstrate the use of pupillary measurements as indices of cognitive workload. We analyze the pupillary data of twenty individuals engaged in a simulated Unmanned Aerial System (UAS) operation in order to understand and characterize the behavior of pupil dilation under varying task load (i.e., workload) levels. We present three metrics that can be employed as real-time indices of cognitive workload. In addition, we develop a predictive system utilizing the pupillary metrics to demonstrate cognitive context detection within simulated supervisory control of UAS. Further, we use pupillary data collected concurrently from the left and right eye and present comparative results of the use of separate vs. combined pupillary data for detecting cognitive context.

  7. An acid/alkaline stress and the addition of amino acids induce a prolonged viability of Lactobacillus plantarum loaded into alginate gel.

    PubMed

    Bevilacqua, Antonio; Sinigaglia, Milena; Corbo, Maria Rosaria

    2010-08-15

    This study reports on the investigation on the effects of the conditions used throughout the step of biomass production on the survival of Lactobacillus plantarum loaded into alginate gels. L. plantarum was grown under different conditions (MRS or a laboratory medium-LB(2)-at acidic or alkaline pHs, with NaCl, phenols, vitamins or amino acids) and immobilized in sodium alginate; cell number was evaluated throughout the storage and death (delta(stand)) and first-reduction times (delta) were calculated. The storage of alginate gels at 4 degrees C prolonged cell viability up to 60 days (ca. 20 days for cells produced in MRS and stored at 30 degrees C); however, a similar prolongation was achieved for cells produced in LB(2) adjusted to pH 5.0 and 9.0 or added with amino acids (death time>50-60 days).

  8. Working Memory Load Modulates Distractor Competition in Primary Visual Cortex

    PubMed Central

    Lavie, Nilli

    2011-01-01

    When stimuli compete for sensory processing and response selection, coherent goal-guided behavior requires cognitive control so that task-relevant “targets” rather than irrelevant distractors are selected. It has been shown that reduced cognitive control under high working memory load increases distractor competition for selection. It remains unknown, though, whether cognitive control by working memory has an effect on the earliest levels of sensory processing in primary visual cortex. The present study addressed this question by having subjects perform a selective attention task involving classification of meaningful target objects while also ignoring congruent and incongruent distractor images. The level of cognitive control over distractor competition was varied through a concurrent working memory task of either low (1 digit) or high (6 digits) load. Functional magnetic resonance imaging revealed greater distractor competition effects not only on behavior but also on the sensory correlates in primary visual cortex (areas V1–V2) in conditions of high (vs. low) working memory load. In addition, high working memory load resulted in increased congruency-related functional connectivity between anterior cingulate cortex and V1. These results are the first to establish the neural correlates of distractor competition effects in primary visual cortex and the critical role of working memory in their cognitive control. PMID:20699229

  9. Cognitive Bases of Human Creativity

    ERIC Educational Resources Information Center

    Sweller, John

    2009-01-01

    Cognitive load theory has been concerned primarily with techniques that will facilitate the acquisition by students of knowledge previously generated by others and deemed to be important by society. The initial generation of that knowledge, a creative process, has been largely ignored. The recent expansion of cognitive load theory's cognitive…

  10. Amelioration of the typical cognitive phenotype in a patient with the 5pter deletion associated with Cri-du-chat syndrome in addition to a partial duplication of CTNND2.

    PubMed

    Sardina, Jennifer M; Walters, Allyson R; Singh, Kathryn E; Owen, Renius X; Kimonis, Virginia E

    2014-07-01

    Cri-du-chat is a rare congenital syndrome characterized by intellectual disability, severe speech/developmental delay, dysmorphic features, and additional syndromic findings. The etiology of this disorder is well known, and is attributed to a large deletion on chromosome 5 that typically ranges from band 5p15.2 to the short arm terminus. This region contains CTNND2, a gene encoding a neuronal-specific protein, delta-catenin, which plays a critical role in cellular motility and brain function. The exact involvement of CTNND2 in the cognitive functionality of individuals with Cri-du-chat has not been fully deciphered, but it is thought to be significant. This report describes an 8-year-old African-American female with a complex chromosome 5 abnormality and a relatively mild case of cri-du-chat syndrome. Because of the surprisingly mild cognitive phenotype, although a karyotype had confirmed the 5p deletion at birth, an oligo-SNP microarray was obtained to further characterize her deletion. The array revealed a complex rearrangement, including a breakpoint in the middle of CTNND2, which resulted in a partial deletion and partial duplication of that gene. The array also verified the expected 5p terminal deletion. Although the patient has a significant deletion in CTNND2, half of the gene (including the promoter region) is not only preserved, but is duplicated. The patient's milder cognitive and behavioral presentation, in conjunction with her atypical 5p alteration, provides additional evidence for the role of CTNND2 in the cognitive phenotype of individuals with Cri-du-chat.

  11. Age-Sensitive Effects of Enduring Work with Alternating Cognitive and Physical Load. A Study Applying Mobile EEG in a Real Life Working Scenario.

    PubMed

    Wascher, Edmund; Heppner, Holger; Kobald, Sven O; Arnau, Stefan; Getzmann, Stephan; Möckel, Tina

    2015-01-01

    Ergonomic assessment of a workplace requires the evaluation of physical as well as cognitive aspects of a particular working situation. In particular the latter is hardly possible without interfering in the natural setting. Mobile acquisition of neurophysiological measures (such as parameters of the EEG) may close this gap. At a simulated workplace we tracked older and younger participants with mobile EEG during a 4-5 h work shift. They had to perform either a monotonous cognitive task, a self-paced cognitive task or a self-paced physical task in a predefined order. Self assessment, behavioral performance and spectral measures of the EEG (before most alpha power) indicated that younger participants suffered from monotony. Older adults, on the other hand, were overall impaired by inefficient information processing. This was visible in EEG variations time-locked to eye blinks (blink-related synchronizations), a new measure to investigate cognitive processing in real life environments. Thus, we were able to distinguish between active and passive task-related aspects of mental fatigue without impinging on the natural working situation.

  12. The Effect of Accents on Cognitive Load and Achievement: The Relationship between Students' Accent Perception and Accented Voice Instructions in Students' Achievement

    ERIC Educational Resources Information Center

    Ahn, Jeahyeon

    2010-01-01

    The purpose of this study was to investigate how an instructor's accent influences students' learning achievement. Furthermore, this study also explored how students' accent preference may affect their learning. Unlike native voices, accented voices were not natural to the native speakers; therefore, it required more cognitive resources for…

  13. Age-Sensitive Effects of Enduring Work with Alternating Cognitive and Physical Load. A Study Applying Mobile EEG in a Real Life Working Scenario

    PubMed Central

    Wascher, Edmund; Heppner, Holger; Kobald, Sven O.; Arnau, Stefan; Getzmann, Stephan; Möckel, Tina

    2016-01-01

    Ergonomic assessment of a workplace requires the evaluation of physical as well as cognitive aspects of a particular working situation. In particular the latter is hardly possible without interfering in the natural setting. Mobile acquisition of neurophysiological measures (such as parameters of the EEG) may close this gap. At a simulated workplace we tracked older and younger participants with mobile EEG during a 4–5 h work shift. They had to perform either a monotonous cognitive task, a self-paced cognitive task or a self-paced physical task in a predefined order. Self assessment, behavioral performance and spectral measures of the EEG (before most alpha power) indicated that younger participants suffered from monotony. Older adults, on the other hand, were overall impaired by inefficient information processing. This was visible in EEG variations time-locked to eye blinks (blink-related synchronizations), a new measure to investigate cognitive processing in real life environments. Thus, we were able to distinguish between active and passive task-related aspects of mental fatigue without impinging on the natural working situation. PMID:26793091

  14. Multimedia's Effect on College Students' Quantitative Mental Effort Scores and Qualitative Extraneous Cognitive Load Responses in a Food Science and Human Nutrition Course

    ERIC Educational Resources Information Center

    Andrade, Jeanette; Huang, Wen-Hao David; Bohn, Dawn M.

    2014-01-01

    Effective use of multimedia (MM) in instructional design is critical for student learning, especially for large lecture introductory courses. This study used a mixed-method approach to explore the effect of food science supporting course materials that utilized different MM formats, designed with Cognitive Theory of Multimedia Learning (CTML)…

  15. Physical characteristics of LWRs and SCLWRs loaded by ({sup 233}U-Th-{sup 238}U) oxide fuel with small additions of {sup 231}Pa

    SciTech Connect

    Kulikov, E.G.; Shmelev, A.N.; Apse, V.A.; Kulikov, G.G.

    2007-07-01

    The paper investigates the possibility and attractiveness of using (U-Th) fuel in light-water reactors (LWRs) and in light-water reactors with super-critical coolant parameters (SCLWRs). It is proposed to dilute {sup 233}U with {sup 238}U to enhance the proliferation resistance of this fissionable isotope. If is noteworthy that she idea was put forward for the first time by she well known American physicist and participant of the Manhattan Project Dr. T. Taylor. Various fuel compositions are analyzed and compared on fuel breeding, achievable values of fuel burn-up and cross-sections of parasitic neutron absorption. It is also demonstrated that small {sup 231}Pa additions (several percent) into the fuel allows: to increase fuel burn-up, to achieve more negative temperature reactivity coefficient of coolant and to enhance nonproliferation of the fuel. (authors)

  16. Human-Systems Integration (HSI) and the Network Integration Evaluations (NIEs), Part 3: Mitigating Cognitive Load in Network-Enabled Mission Command

    DTIC Science & Technology

    2016-06-01

    that cognitive work more reliable. Practically speaking , operational integration involves incorporating new mission command materiel solutions into...echelons. • Formal KM training has not been provided to personnel requiring KM skills . 2.3.2 Recommendations The following recommendations are...training for affected personnel. • Consideration should be given to including KM skills in the Mission Command DMG course. This action would assist in

  17. The cognitive impact of interactive design features for learning complex materials in medical education

    PubMed Central

    Song, Hyuksoon S.; Pusic, Martin; Nick, Michael W.; Sarpel, Umut; Plass, Jan L.; Kalet, Adina L.

    2013-01-01

    To identify the most effective way for medical students to interact with a browser-based learning module on the symptoms and neurological underpinnings of stroke syndromes, this study manipulated the way in which subjects interacted with a graphical model of the brain and examined the impact of functional changes on learning outcomes. It was hypothesized that behavioral interactions that were behaviorally more engaging and which required deeper consideration of the model would result in heightened cognitive interaction and better learning than those whose manipulation required less deliberate behavioral and cognitive processing. One hundred forty four students were randomly assigned to four conditions whose model controls incorporated features that required different levels of behavioral and cognitive interaction: Movie (low behavioral/low cognitive, n = 40), Slider (high behavioral/low cognitive, n = 36), Click (low behavioral/high cognitive, n = 30), and Drag (high behavioral/high cognitive, n = 38). Analysis of Covariates (ANCOVA) showed that students who received the treatments associated with lower cognitive interactivity (Movie and Slider) performed better on a transfer task than those receiving the module associated with high cognitive interactivity (Click and Drag, partial eta squared = .03). In addition, the students in the high cognitive interactivity conditions spent significantly more time on the stroke locator activity than other conditions (partial eta squared = .36). The results suggest that interaction with controls that were tightly coupled with the model and whose manipulation required deliberate consideration of the model’s features may have overtaxed subjects’ cognitive resources. Cognitive effort that facilitated manipulation of content, though directed at the model, may have resulted in extraneous cognitive load, impeding subjects in recognizing the deeper, global relationships in the materials. Instructional designers must, therefore

  18. Cognitive Processes that Account for Mental Addition Fluency Differences between Children Typically Achieving in Arithmetic and Children At-Risk for Failure in Arithmetic

    ERIC Educational Resources Information Center

    Berg, Derek H.; Hutchinson, Nancy L.

    2010-01-01

    This study investigated whether processing speed, short-term memory, and working memory accounted for the differential mental addition fluency between children typically achieving in arithmetic (TA) and children at-risk for failure in arithmetic (AR). Further, we drew attention to fluency differences in simple (e.g., 5 + 3) and complex (e.g., 16 +…

  19. Intact brain processing of musical emotions in autism spectrum disorder, but more cognitive load and arousal in happy vs. sad music

    PubMed Central

    Gebauer, Line; Skewes, Joshua; Westphael, Gitte; Heaton, Pamela; Vuust, Peter

    2014-01-01

    Music is a potent source for eliciting emotions, but not everybody experience emotions in the same way. Individuals with autism spectrum disorder (ASD) show difficulties with social and emotional cognition. Impairments in emotion recognition are widely studied in ASD, and have been associated with atypical brain activation in response to emotional expressions in faces and speech. Whether these impairments and atypical brain responses generalize to other domains, such as emotional processing of music, is less clear. Using functional magnetic resonance imaging, we investigated neural correlates of emotion recognition in music in high-functioning adults with ASD and neurotypical adults. Both groups engaged similar neural networks during processing of emotional music, and individuals with ASD rated emotional music comparable to the group of neurotypical individuals. However, in the ASD group, increased activity in response to happy compared to sad music was observed in dorsolateral prefrontal regions and in the rolandic operculum/insula, and we propose that this reflects increased cognitive processing and physiological arousal in response to emotional musical stimuli in this group. PMID:25076869

  20. Intact brain processing of musical emotions in autism spectrum disorder, but more cognitive load and arousal in happy vs. sad music.

    PubMed

    Gebauer, Line; Skewes, Joshua; Westphael, Gitte; Heaton, Pamela; Vuust, Peter

    2014-01-01

    Music is a potent source for eliciting emotions, but not everybody experience emotions in the same way. Individuals with autism spectrum disorder (ASD) show difficulties with social and emotional cognition. Impairments in emotion recognition are widely studied in ASD, and have been associated with atypical brain activation in response to emotional expressions in faces and speech. Whether these impairments and atypical brain responses generalize to other domains, such as emotional processing of music, is less clear. Using functional magnetic resonance imaging, we investigated neural correlates of emotion recognition in music in high-functioning adults with ASD and neurotypical adults. Both groups engaged similar neural networks during processing of emotional music, and individuals with ASD rated emotional music comparable to the group of neurotypical individuals. However, in the ASD group, increased activity in response to happy compared to sad music was observed in dorsolateral prefrontal regions and in the rolandic operculum/insula, and we propose that this reflects increased cognitive processing and physiological arousal in response to emotional musical stimuli in this group.

  1. A simple approach to obtain hybrid Au-loaded polymeric nanoparticles with a tunable metal load† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06850a Click here for additional data file.

    PubMed Central

    Luque-Michel, Edurne; Larrea, Ane; Lahuerta, Celia; Imbuluzqueta, Edurne; Arruebo, Manuel; Santamaría, Jesús

    2016-01-01

    A new strategy to nanoengineer multi-functional polymer–metal hybrid nanostructures is reported. By using this protocol the hurdles of most of the current developments concerning covalent and non-covalent attachment of polymers to preformed inorganic nanoparticles (NPs) are overcome. The strategy is based on the in situ reduction of metal precursors using the polymeric nanoparticle as a nanoreactor. Gold nanoparticles and poly(dl-lactic-co-glycolic acid), PLGA, are located in the core and shell, respectively. This novel technique enables the production of PLGA NPs smaller than 200 nm that bear either a single encapsulated Au NP or several smaller NPs with tunable sizes and a 100% loading efficiency. In situ reduction of Au ions inside the polymeric NPs was achieved on demand by using heat to activate the reductive effect of citrate ions. In addition, we show that the loading of the resulting Au NPs inside the PLGA NPs is highly dependent on the surfactant used. Electron microscopy, laser irradiation, UV-Vis and fluorescence spectroscopy characterization techniques confirm the location of Au nanoparticles. These promising results indicate that these hybrid nanomaterials could be used in theranostic applications or as contrast agents in dark-field imaging and computed tomography. PMID:26612770

  2. Moment to moment variability in functional brain networks during cognitive activity in EEG data.

    PubMed

    Dasari, Naga M; Nandagopal, Nanda D; Ramasamy, Vijayalaxmi; Cocks, Bernadine; Thomas, Bruce H; Dahal, Nabaraj; Gaertner, Paul

    2015-09-01

    Functional brain networks (FBNs) are gaining increasing attention in computational neuroscience due to their ability to reveal dynamic interdependencies between brain regions. The dynamics of such networks during cognitive activity between stimulus and response using multi-channel electroencephalogram (EEG), recorded from 16 healthy human participants are explored in this research. Successive EEG segments of 500[Formula: see text]ms duration starting from the onset of cognitive stimulation have been used to analyze and understand the cognitive dynamics. The approach employs a combination of signal processing techniques, nonlinear statistical measures and graph-theoretical analysis. The efficacy of this approach in detecting and tracking cognitive load induced changes in EEG data is clearly demonstrated using graph metrics. It is revealed that most cognitive activity occurs within approximately 500[Formula: see text]ms of the stimulus presentation in addition to temporal variability in the FBNs. It is shown that mutual information (MI), a nonlinear measure, produces good correlations between the EEG channels thus enabling the construction of FBNs which are sensitive to cognitive load induced changes in EEG. Analyses of the dynamics of FBNs and the visualization approach reveal hard to detect subtle changes in cognitive function and hence may lead to a better understanding of cognitive processing in the brain. The techniques exploited have the potential to detect human cognitive dysfunction (impairments).

  3. Additive microglia-mediated neuronal injury caused by amyloid-β and bacterial TLR agonists in murine neuron-microglia co-cultures quantified by an automated image analysis using cognition network technology.

    PubMed

    Schütze, Sandra; Loleit, Tobias; Zeretzke, Moritz; Bunkowski, Stephanie; Brück, Wolfgang; Ribes, Sandra; Nau, Roland

    2012-01-01

    Activated microglia is considered to be involved in the progression of Alzheimer's disease (AD). We investigated the effect of amyloid-β(1-40) (Aβ(40) and exogenous agonists of Toll-like receptor (TLR) 1/2 (Pam(3)CSK(4)) and TLR4 (LPS) on neurons in primary murine neuron-microglia co-cultures. Neuronal viability, assessed by quantifying the number of intact neuronal extensions and their crossings using a newly developed Definiens Cognition Network Technology-based method, was significantly decreased after treatment with Pam(3)CSK(4), LPS, and Aβ(40). Combined treatment with Aβ(40) and Pam(3)CSK(4) or LPS had an additive effect. Hence, in patients with AD, synergistic microglial activation by Aβ and bacterial products during infections might contribute to disease progression.

  4. Load cell

    DOEpatents

    Spletzer, Barry L.

    1998-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components.

  5. Load cell

    DOEpatents

    Spletzer, B.L.

    1998-12-15

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components. 16 figs.

  6. Load cell

    DOEpatents

    Spletzer, Barry L.

    2001-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs which can be combined to determine any one of the six general load components.

  7. A dual brain-targeting curcumin-loaded polymersomes ameliorated cognitive dysfunction in intrahippocampal amyloid-β1-42-injected mice.

    PubMed

    Jia, Tingting; Sun, Zhiguo; Lu, Ying; Gao, Jie; Zou, Hao; Xie, Fangyuan; Zhang, Guoqing; Xu, Hao; Sun, Duxin; Yu, Yuan; Zhong, Yanqiang

    2016-01-01

    Due to the impermeability of the blood-brain barrier and the nonselective distribution of drugs in the brain, the therapeutic access to intractable neurological disorders is challenging. In this study, dual brain-targeting polymersomes (POs) functionalized by transferrin and Tet-1 peptide (Tf/Tet-1-POs) promoted the transportation of curcumin into the brain and provided neuroprotection. The modification of the ligands that bind to the surface of POs was revealed by X-ray photoelectron spectroscopy analysis. The cell uptake of a coculture model of mouse brain capillary endothelial cells with neurons showed that the Tf/Tet-1-POs had significant transportation properties and possessed affinity for neurons. The pharmacokinetic analysis showed that the blood-brain barrier permeability-surface efficiency of the Tf/Tet-1-POs was 0.28 mL/h/g and that the brain tissue uptake rate (% ID/g) was 0.08, which were significant compared with the controls (P<0.05). The curcumin-encapsulated Tf/Tet-1-POs provided neuroprotection and ameliorated cognitive dysfunction in intrahippocampal amyloid-β1-42-injected mice. These results suggest that the dual brain-targeting POs are more capable of drug delivery to the brain that can be exploited as a multiple noninvasive vehicle for targeting therapeutics.

  8. A dual brain-targeting curcumin-loaded polymersomes ameliorated cognitive dysfunction in intrahippocampal amyloid-β1–42-injected mice

    PubMed Central

    Jia, Tingting; Sun, Zhiguo; Lu, Ying; Gao, Jie; Zou, Hao; Xie, Fangyuan; Zhang, Guoqing; Xu, Hao; Sun, Duxin; Yu, Yuan; Zhong, Yanqiang

    2016-01-01

    Due to the impermeability of the blood–brain barrier and the nonselective distribution of drugs in the brain, the therapeutic access to intractable neurological disorders is challenging. In this study, dual brain-targeting polymersomes (POs) functionalized by transferrin and Tet-1 peptide (Tf/Tet-1-POs) promoted the transportation of curcumin into the brain and provided neuroprotection. The modification of the ligands that bind to the surface of POs was revealed by X-ray photoelectron spectroscopy analysis. The cell uptake of a coculture model of mouse brain capillary endothelial cells with neurons showed that the Tf/Tet-1-POs had significant transportation properties and possessed affinity for neurons. The pharmacokinetic analysis showed that the blood–brain barrier permeability–surface efficiency of the Tf/Tet-1-POs was 0.28 mL/h/g and that the brain tissue uptake rate (% ID/g) was 0.08, which were significant compared with the controls (P<0.05). The curcumin-encapsulated Tf/Tet-1-POs provided neuroprotection and ameliorated cognitive dysfunction in intrahippocampal amyloid-β1–42-injected mice. These results suggest that the dual brain-targeting POs are more capable of drug delivery to the brain that can be exploited as a multiple noninvasive vehicle for targeting therapeutics. PMID:27540290

  9. Cancer, Coping, and Cognition: A Model for the Role of Stress Reactivity in Cancer-Related Cognitive Decline

    PubMed Central

    Andreotti, Charissa; Root, James C.; Ahles, Tim A.; McEwen, Bruce S.; Compas, Bruce E.

    2014-01-01

    Cognitive decline and accompanying neurological changes associated with non-CNS cancer diagnosis and treatment have been increasingly identified in a subset of patients. Initially believed to be due to neurotoxic effects of chemotherapy exposure, observation of cognitive decline in patients not treated with chemotherapy, cancer-diagnosed individuals prior to treatment, and patients receiving alternative treatment modalities (surgery, endocrine therapy, radiation), has led to investigation of additional potential etiologies and moderating factors. Stressful experiences have long been posited as a contributor to these cognitive changes. Through reciprocal connectivity with peripheral systems, the brain maintains a dynamic circuitry to adapt to stress (allostasis). However, overuse of this system leads to dysregulation and contributes to pathophysiology (allostatic load). At this time, little research has been conducted to systematically examine the role of allostatic load in cancer-related cognitive dysfunction. Here we integrate theories of stress biology, neuropsychology, and coping and propose a model through which individuals with a high level of allostatic load at diagnosis may be particularly vulnerable to the neurocognitive effects of cancer. Opportunities for future research to test and extend proposed mechanisms are discussed in addition to points of prevention and intervention based on individual variation in stress reactivity and coping skills. PMID:25286084

  10. The eye as a window to the listening brain: neural correlates of pupil size as a measure of cognitive listening load.

    PubMed

    Zekveld, Adriana A; Heslenfeld, Dirk J; Johnsrude, Ingrid S; Versfeld, Niek J; Kramer, Sophia E

    2014-11-01

    An important aspect of hearing is the degree to which listeners have to deploy effort to understand speech. One promising measure of listening effort is task-evoked pupil dilation. Here, we use functional magnetic resonance imaging (fMRI) to identify the neural correlates of pupil dilation during comprehension of degraded spoken sentences in 17 normal-hearing listeners. Subjects listened to sentences degraded in three different ways: the target female speech was masked by fluctuating noise, by speech from a single male speaker, or the target speech was noise-vocoded. The degree of degradation was individually adapted such that 50% or 84% of the sentences were intelligible. Control conditions included clear speech in quiet, and silent trials. The peak pupil dilation was larger for the 50% compared to the 84% intelligibility condition, and largest for speech masked by the single-talker masker, followed by speech masked by fluctuating noise, and smallest for noise-vocoded speech. Activation in the bilateral superior temporal gyrus (STG) showed the same pattern, with most extensive activation for speech masked by the single-talker masker. Larger peak pupil dilation was associated with more activation in the bilateral STG, bilateral ventral and dorsal anterior cingulate cortex and several frontal brain areas. A subset of the temporal region sensitive to pupil dilation was also sensitive to speech intelligibility and degradation type. These results show that pupil dilation during speech perception in challenging conditions reflects both auditory and cognitive processes that are recruited to cope with degraded speech and the need to segregate target speech from interfering sounds.

  11. The Role of Mental Load in Inattentional Blindness

    ERIC Educational Resources Information Center

    Perez-Moreno, Elisa; Conchillo, Angela; Recarte, Miguel A.

    2011-01-01

    The purpose of this investigation is to determine whether the mental load of a cognitive task prevents the processing of visual stimuli, that is, whether the mental load produces inattentional blindness, and at what point in the cognitive-task processing more interference is produced. An arithmetic task with two levels of mental load was used in a…

  12. Podcasting, Cognitive Theory, and Really Simple Syndication: What Is the Potential Impact when Used Together?

    ERIC Educational Resources Information Center

    Lori, Andersen

    2011-01-01

    The addition of video capabilities to portable media playing devices has engendered a broader definition of the term podcast to include video files. Current research designs on podcast use in education are neglectful of the considerations of cognitive load on student learning. Podcasting is the process by which multimedia learning objects (MLOs)…

  13. Visual short-term memory load reduces retinotopic cortex response to contrast.

    PubMed

    Konstantinou, Nikos; Bahrami, Bahador; Rees, Geraint; Lavie, Nilli

    2012-11-01

    Load Theory of attention suggests that high perceptual load in a task leads to reduced sensory visual cortex response to task-unrelated stimuli resulting in "load-induced blindness" [e.g., Lavie, N. Attention, distraction and cognitive control under load. Current Directions in Psychological Science, 19, 143-148, 2010; Lavie, N. Distracted and confused?: Selective attention under load. Trends in Cognitive Sciences, 9, 75-82, 2005]. Consideration of the findings that visual STM (VSTM) involves sensory recruitment [e.g., Pasternak, T., & Greenlee, M. Working memory in primate sensory systems. Nature Reviews Neuroscience, 6, 97-107, 2005] within Load Theory led us to a new hypothesis regarding the effects of VSTM load on visual processing. If VSTM load draws on sensory visual capacity, then similar to perceptual load, high VSTM load should also reduce visual cortex response to incoming stimuli leading to a failure to detect them. We tested this hypothesis with fMRI and behavioral measures of visual detection sensitivity. Participants detected the presence of a contrast increment during the maintenance delay in a VSTM task requiring maintenance of color and position. Increased VSTM load (manipulated by increased set size) led to reduced retinotopic visual cortex (V1-V3) responses to contrast as well as reduced detection sensitivity, as we predicted. Additional visual detection experiments established a clear tradeoff between the amount of information maintained in VSTM and detection sensitivity, while ruling out alternative accounts for the effects of VSTM load in terms of differential spatial allocation strategies or task difficulty. These findings extend Load Theory to demonstrate a new form of competitive interactions between early visual cortex processing and visual representations held in memory under load and provide a novel line of support for the sensory recruitment hypothesis of VSTM.

  14. No Negative Priming without Cognitive Control

    ERIC Educational Resources Information Center

    de Fockert, Jan W.; Mizon, Guy A.; D'Ubaldo, Mariangela

    2010-01-01

    There is evidence that the efficiency of selective attention depends on the availability of cognitive control mechanisms as distractor processing has been found to increase with high load on working memory or dual task coordination (Lavie, Hirst, de Fockert, & Viding, 2004). We tested the prediction that cognitive control load would also…

  15. Is take-over time all that matters? The impact of visual-cognitive load on driver take-over quality after conditionally automated driving.

    PubMed

    Zeeb, Kathrin; Buchner, Axel; Schrauf, Michael

    2016-07-01

    Currently, development of conditionally automated driving systems which control both lateral and longitudinal vehicle guidance is attracting a great deal of attention. The driver no longer needs to constantly monitor the roadway, but must still be able to resume vehicle control if necessary. The relaxed attention requirement might encourage engagement in non-driving related secondary tasks, and the resulting effect on driver take-over is unclear. The aim of this study was to examine how engagement in three different naturalistic secondary tasks (writing an email, reading a news text, watching a video clip) impacted take-over performance. A driving simulator study was conducted and data from a total of 79 participants (mean age 40 years, 35 females) were used to examine response times and take-over quality. Drivers had to resume vehicle control in four different non-critical scenarios while engaging in secondary tasks. A control group did not perform any secondary tasks. There was no influence of the drivers' engagement in secondary tasks on the time required to return their hands to the steering wheel, and there seemed to be only little if any influence on the time the drivers needed to intervene in vehicle control. Take-over quality, however, deteriorated for distracted drivers, with drivers reading a news text and drivers watching a video deviating on average approximately 8-9cm more from the lane center. These findings seem to indicate that establishing motor readiness may be carried out almost reflexively, but cognitive processing of the situation is impaired by driver distraction. This, in turn, appears to determine take-over quality. The present findings emphasize the importance to consider both response times and take-over quality for a comprehensive understanding of factors that influence driver take-over. Furthermore, a training effect in response times was found to be moderated by the drivers' prior experience with driver assistance systems. This shows

  16. Cognitive Design Patterns

    DTIC Science & Technology

    2008-06-01

    GUI builder ( Glade , in this case). The area highlighted by the oval shows where a modular CWE toolbar would be loaded into the application. The...Vancouver, BC. [7] Dave O’Malley, Jon Zall, John Colombi, and Joe Carl. Integrating Cognition into System Design. 2008 International Conference on Software Engineering, Research, and Practice. Las Vegas, NV.

  17. Structural network connectivity and cognition in cerebral small vessel disease.

    PubMed

    Tuladhar, Anil M; van Dijk, Ewoud; Zwiers, Marcel P; van Norden, Anouk G W; de Laat, Karlijn F; Shumskaya, Elena; Norris, David G; de Leeuw, Frank-Erik

    2016-01-01

    Cerebral small vessel disease (SVD), including white matter hyperintensities (WMH), lacunes and microbleeds, and brain atrophy, are related to cognitive impairment. However, these magnetic resonance imaging (MRI) markers for SVD do not account for all the clinical variances observed in subjects with SVD. Here, we investigated the relation between conventional MRI markers for SVD, network efficiency and cognitive performance in 436 nondemented elderly with cerebral SVD. We computed a weighted structural connectivity network from the diffusion tensor imaging and deterministic streamlining. We found that SVD-severity (indicated by higher WMH load, number of lacunes and microbleeds, and lower total brain volume) was related to networks with lower density, connection strengths, and network efficiency, and to lower scores on cognitive performance. In multiple regressions models, network efficiency remained significantly associated with cognitive index and psychomotor speed, independent of MRI markers for SVD and mediated the associations between these markers and cognition. This study provides evidence that network (in)efficiency might drive the association between SVD and cognitive performance. This highlights the importance of network analysis in our understanding of SVD-related cognitive impairment in addition to conventional MRI markers for SVD and might provide an useful tool as disease marker.

  18. What can biomarkers tell us about cognition in Parkinson's disease?

    PubMed

    Mollenhauer, Brit; Rochester, Lynn; Chen-Plotkin, Alice; Brooks, David

    2014-04-15

    Cognitive decline is common in Parkinson's disease (PD), even in the early motor stage, and this non-motor feature impacts quality of life and prognosis tremendously. In this article, we discuss marker candidates for cognitive decline in PD from different angles, including functional and structural imaging techniques, biological fluid markers in cerebrospinal fluid, and blood genetic predictors, as well as gait as a surrogate marker of cognitive decline. Specifically, imaging-based markers of cognitive impairment in PD include cortical atrophy, reduced cortical metabolism, loss of cortical cholinergic and frontal dopaminergic function, as well as an increased cortical amyloid load. Reduced β-amyloid(1-42) in cerebrospinal fluid and lower plasma levels of epidermal growth factor are predictors for cognitive decline in PD. In addition, genetic variation in the apolipoprotein E (APOE), catechol-O-methyltransferase (COMT), microtubule-associated protein tau (MAPT), and glucocerebrosidase (GBA) genes may confer risk for cognitive impairment in PD; and gait disturbance may also indicate an increased risk for dementia. Other marker candidates have been proposed and are discussed. All of the current studies are hampered by gaps in our knowledge about the molecular causes of cognitive decline, which will have to be considered in future biomarker studies.

  19. Reciprocal Relations Between Cognitive Neuroscience and Cognitive Models: Opposites Attract?

    PubMed Central

    Forstmann, Birte U.; Wagenmakers, Eric-Jan; Eichele, Tom; Brown, Scott; Serences, John T.

    2012-01-01

    Cognitive neuroscientists study how the brain implements particular cognitive processes such as perception, learning, and decision-making. Traditional approaches in which experiments are designed to target a specific cognitive process have been supplemented by two recent innovations. First, formal models of cognition can decompose observed behavioral data into multiple latent cognitive processes, allowing brain measurements to be associated with a particular cognitive process more precisely and more confidently. Second, cognitive neuroscience can provide additional data to inform the development of cognitive models, providing greater constraint than behavioral data alone. We argue that these fields are mutually dependent: not only can models guide neuroscientific endeavors, but understanding neural mechanisms can provide critical insights into formal models of cognition. PMID:21612972

  20. Assessing Spatial Cognition in Stereoscopic Environments

    NASA Astrophysics Data System (ADS)

    Price, Aaron; Lee, H.

    2008-05-01

    Nineteen middle-school aged students visiting a planetarium were presented with three visuospatial tasks in both 2D (paper) and stereoscopic environments. The students' performance on tasks was evaluated in order to determine the impact of stereoscopic presentation upon accuracy and task completion time. Results show that accuracy did not differ between the two representational environments while completion time was greater for the stereoscopic environment. Post task interviews show that spatial and temporal discontiguity increased the cognitive load. Additionally, the interviews showed that students continued to visualize in two dimensions while using the stereoscopic representations.

  1. Vascular and amyloid pathologies are independent predictors of cognitive decline in normal elderly

    PubMed Central

    Lesnick, Timothy G.; Przybelski, Scott A.; Knopman, David S.; Preboske, Greg M.; Kantarci, Kejal; Raman, Mekala R.; Machulda, Mary M.; Mielke, Michelle M.; Lowe, Val J.; Senjem, Matthew L.; Gunter, Jeffrey L.; Rocca, Walter A.; Roberts, Rosebud O.; Petersen, Ronald C.; Jack, Clifford R.

    2015-01-01

    Our primary objective was to investigate a biomarker driven model for the interrelationships between vascular disease pathology, amyloid pathology, and longitudinal cognitive decline in cognitively normal elderly subjects between 70 and 90 years of age. Our secondary objective was to investigate the beneficial effect of cognitive reserve on these interrelationships. We used brain amyloid-β load measured using Pittsburgh compound B positron emission tomography as a marker for amyloid pathology. White matter hyperintensities and brain infarcts were measured using fluid-attenuated inversion recovery magnetic resonance imaging as a marker for vascular pathology. We studied 393 cognitively normal elderly participants in the population-based Mayo Clinic Study of Aging who had a baseline 3 T fluid-attenuated inversion recovery magnetic resonance imaging assessment, Pittsburgh compound B positron emission tomography scan, baseline cognitive assessment, lifestyle measures, and at least one additional clinical follow-up. We classified subjects as being on the amyloid pathway if they had a global cortical amyloid-β load of ≥1.5 standard uptake value ratio and those on the vascular pathway if they had a brain infarct and/or white matter hyperintensities load ≥1.11% of total intracranial volume (which corresponds to the top 25% of white matter hyperintensities in an independent non-demented sample). We used a global cognitive z-score as a measure of cognition. We found no evidence that the presence or absence of vascular pathology influenced the presence or absence of amyloid pathology and vice versa, suggesting that the two processes seem to be independent. Baseline cognitive performance was lower in older individuals, in males, those with lower education/occupation, and those on the amyloid pathway. The rate of cognitive decline was higher in older individuals (P < 0.001) and those with amyloid (P = 0.0003) or vascular (P = 0.0037) pathologies. In those subjects with

  2. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  3. Robust Multimodal Cognitive Load Measurement (RMCLM)

    DTIC Science & Technology

    2013-03-26

    ulus). The segment names are added to each feature name as suffixes to denote the segmentation scheme. This was to eval- uatewhich task stimulus...n2]. We add a ‘−M’ suffix to the raw feature name (fn), for example, PDM[n], BDM[n], BDurM[n], SDM[n], FDurM[n], SAmpM[n], to denote the means of the...vironments, despite the fact that many operators use an array of low-tech tools, such as physical paper and pen to support their work processes. Indeed

  4. Reciprocal Tutoring: Design with Cognitive Load Sharing

    ERIC Educational Resources Information Center

    Chou, Chih-Yueh; Chan, Tak-Wai

    2016-01-01

    "Reciprocal tutoring," as reported in "Exploring the design of computer supports for reciprocal tutoring" (Chan and Chou 1997), has extended the meaning and scope of "intelligent tutoring" originally implemented in stand alone computers. This research is a follow-up to our studies on a "learning companion…

  5. Alpha frequency, cognitive load and memory performance.

    PubMed

    Klimesch, W; Schimke, H; Pfurtscheller, G

    1993-01-01

    EEG-signals were recorded from subjects as they performed a modified version of Schneider's and Shiffrin's memory search paradigm. The hypothesis was tested whether individual (centre of gravity) alpha frequency, termed IAF, is related to memory performance and/or attentional demands. The results show that memory performance exerts the strongest effect on IAF. As compared to a resting period, the difference in IAF between age-matched good and bad memory performers reached a maximum when subjects were actually retrieving information from their memory. During retrieval, the IAF of good performers is 1.25 Hz higher than for bad performers. Attentional and task demands also tend to reduce IAF, but as compared to memory performance-to a much lesser degree. The results of amplitude analyses demonstrate further that during retrieval, alpha desynchronization is more pronounced for bad performers than for good performers. Taken together, the results indicate that a decrease in IAF is always related to a drop in performance.

  6. Declarative strategies persist under increased cognitive load.

    PubMed

    Crossley, Matthew J; Paul, Erick J; Roeder, Jessica L; Ashby, F Gregory

    2016-02-01

    When humans simultaneously execute multiple tasks, performance on individual tasks suffers. Complementing existing theories, this article poses a novel question to investigate interactions between memory systems supporting multi-tasking performance: When a primary and dual task both recruit declarative learning and memory systems, does simultaneous performance of both tasks impair primary task performance because learning in the declarative system is reduced, or because control of the primary task is passed to slower procedural systems? To address this question, participants were trained on either a perceptual categorization task believed to rely on procedural learning or one of three different categorization tasks believed to rely on declarative learning. Task performance was examined with and without a simultaneous dual task thought to recruit working memory and executive attention. To test whether the categories were learned procedurally or declaratively, the response keys were switched after a learning criterion had been reached. Large impairments in performance after switching the response keys are taken to indicate procedural learning, and small impairments are taken to indicate declarative learning. Our results suggest that the declarative memory categorization tasks (regardless of task difficulty) were learned by declarative systems, regardless of whether they were learned under dual-task conditions.

  7. Cognitive ecology.

    PubMed

    Hutchins, Edwin

    2010-10-01

    Cognitive ecology is the study of cognitive phenomena in context. In particular, it points to the web of mutual dependence among the elements of a cognitive ecosystem. At least three fields were taking a deeply ecological approach to cognition 30 years ago: Gibson's ecological psychology, Bateson's ecology of mind, and Soviet cultural-historical activity theory. The ideas developed in those projects have now found a place in modern views of embodied, situated, distributed cognition. As cognitive theory continues to shift from units of analysis defined by inherent properties of the elements to units defined in terms of dynamic patterns of correlation across elements, the study of cognitive ecosystems will become an increasingly important part of cognitive science.

  8. Cognitive Network Neuroscience

    PubMed Central

    Medaglia, John D.; Lynall, Mary-Ellen; Bassett, Danielle S.

    2016-01-01

    Network science provides theoretical, computational, and empirical tools that can be used to understand the structure and function of the human brain in novel ways using simple concepts and mathematical representations. Network neuroscience is a rapidly growing field that is providing considerable insight into human structural connectivity, functional connectivity while at rest, changes in functional networks over time (dynamics), and how these properties differ in clinical populations. In addition, a number of studies have begun to quantify network characteristics in a variety of cognitive processes and provide a context for understanding cognition from a network perspective. In this review, we outline the contributions of network science to cognitive neuroscience. We describe the methodology of network science as applied to the particular case of neuroimaging data and review its uses in investigating a range of cognitive functions including sensory processing, language, emotion, attention, cognitive control, learning, and memory. In conclusion, we discuss current frontiers and the specific challenges that must be overcome to integrate these complementary disciplines of network science and cognitive neuroscience. Increased communication between cognitive neuroscientists and network scientists could lead to significant discoveries under an emerging scientific intersection known as cognitive network neuroscience. PMID:25803596

  9. Cognitive network neuroscience.

    PubMed

    Medaglia, John D; Lynall, Mary-Ellen; Bassett, Danielle S

    2015-08-01

    Network science provides theoretical, computational, and empirical tools that can be used to understand the structure and function of the human brain in novel ways using simple concepts and mathematical representations. Network neuroscience is a rapidly growing field that is providing considerable insight into human structural connectivity, functional connectivity while at rest, changes in functional networks over time (dynamics), and how these properties differ in clinical populations. In addition, a number of studies have begun to quantify network characteristics in a variety of cognitive processes and provide a context for understanding cognition from a network perspective. In this review, we outline the contributions of network science to cognitive neuroscience. We describe the methodology of network science as applied to the particular case of neuroimaging data and review its uses in investigating a range of cognitive functions including sensory processing, language, emotion, attention, cognitive control, learning, and memory. In conclusion, we discuss current frontiers and the specific challenges that must be overcome to integrate these complementary disciplines of network science and cognitive neuroscience. Increased communication between cognitive neuroscientists and network scientists could lead to significant discoveries under an emerging scientific intersection known as cognitive network neuroscience.

  10. Food additives

    MedlinePlus

    ... or natural. Natural food additives include: Herbs or spices to add flavor to foods Vinegar for pickling ... Certain colors improve the appearance of foods. Many spices, as well as natural and man-made flavors, ...

  11. The complex interaction between anxiety and cognition: insight from spatial and verbal working memory.

    PubMed

    Vytal, Katherine E; Cornwell, Brian R; Letkiewicz, Allison M; Arkin, Nicole E; Grillon, Christian

    2013-01-01

    Anxiety can be distracting, disruptive, and incapacitating. Despite problems with empirical replication of this phenomenon, one fruitful avenue of study has emerged from working memory (WM) experiments where a translational method of anxiety induction (risk of shock) has been shown to disrupt spatial and verbal WM performance. Performance declines when resources (e.g., spatial attention, executive function) devoted to goal-directed behaviors are consumed by anxiety. Importantly, it has been shown that anxiety-related impairments in verbal WM depend on task difficulty, suggesting that cognitive load may be an important consideration in the interaction between anxiety and cognition. Here we use both spatial and verbal WM paradigms to probe the effect of cognitive load on anxiety-induced WM impairment across task modality. Subjects performed a series of spatial and verbal n-back tasks of increasing difficulty (1, 2, and 3-back) while they were safe or at risk for shock. Startle reflex was used to probe anxiety. Results demonstrate that induced-anxiety differentially impacts verbal and spatial WM, such that low and medium-load verbal WM is more susceptible to anxiety-related disruption relative to high-load, and spatial WM is disrupted regardless of task difficulty. Anxiety impacts both verbal and spatial processes, as described by correlations between anxiety and performance impairment, albeit the effect on spatial WM is consistent across load. Demanding WM tasks may exert top-down control over higher-order cortical resources engaged by anxious apprehension, however high-load spatial WM may continue to experience additional competition from anxiety-related changes in spatial attention, resulting in impaired performance. By describing this disruption across task modalities, these findings inform current theories of emotion-cognition interactions and may facilitate development of clinical interventions that seek to target cognitive impairments associated with anxiety.

  12. An Eight-Eyed Version of Hawkins and Shohet's Clinical Supervision Model: The Addition of the Cognitive Analytic Therapy Concept of the "Observing Eye/I" as the "Observing Us"

    ERIC Educational Resources Information Center

    Darongkamas, Jurai; John, Christopher; Walker, Mark James

    2014-01-01

    This paper proposes incorporating the concept of the "observing eye/I", from cognitive analytic therapy (CAT), to Hawkins and Shohet's seven modes of supervision, comprising their transtheoretical model of supervision. Each mode is described alongside explicit examples relating to CAT. This modification using a key idea from CAT (in…

  13. Distinct and shared cognitive functions mediate event- and time-based prospective memory impairment in normal ageing

    PubMed Central

    Gonneaud, Julie; Kalpouzos, Grégoria; Bon, Laetitia; Viader, Fausto; Eustache, Francis; Desgranges, Béatrice

    2011-01-01

    Prospective memory (PM) is the ability to remember to perform an action at a specific point in the future. Regarded as multidimensional, PM involves several cognitive functions that are known to be impaired in normal aging. In the present study, we set out to investigate the cognitive correlates of PM impairment in normal aging. Manipulating cognitive load, we assessed event- and time-based PM, as well as several cognitive functions, including executive functions, working memory and retrospective episodic memory, in healthy subjects covering the entire adulthood. We found that normal aging was characterized by PM decline in all conditions and that event-based PM was more sensitive to the effects of aging than time-based PM. Whatever the conditions, PM was linked to inhibition and processing speed. However, while event-based PM was mainly mediated by binding and retrospective memory processes, time-based PM was mainly related to inhibition. The only distinction between high- and low-load PM cognitive correlates lays in an additional, but marginal, correlation between updating and the high-load PM condition. The association of distinct cognitive functions, as well as shared mechanisms with event- and time-based PM confirms that each type of PM relies on a different set of processes. PMID:21678154

  14. Cognitive workload modulation through degraded visual stimuli: a single-trial EEG study

    NASA Astrophysics Data System (ADS)

    Yu, K.; Prasad, I.; Mir, H.; Thakor, N.; Al-Nashash, H.

    2015-08-01

    Objective. Our experiments explored the effect of visual stimuli degradation on cognitive workload. Approach. We investigated the subjective assessment, event-related potentials (ERPs) as well as electroencephalogram (EEG) as measures of cognitive workload. Main results. These experiments confirm that degradation of visual stimuli increases cognitive workload as assessed by subjective NASA task load index and confirmed by the observed P300 amplitude attenuation. Furthermore, the single-trial multi-level classification using features extracted from ERPs and EEG is found to be promising. Specifically, the adopted single-trial oscillatory EEG/ERP detection method achieved an average accuracy of 85% for discriminating 4 workload levels. Additionally, we found from the spatial patterns obtained from EEG signals that the frontal parts carry information that can be used for differentiating workload levels. Significance. Our results show that visual stimuli can modulate cognitive workload, and the modulation can be measured by the single trial EEG/ERP detection method.

  15. Extremely fast increase in the organic loading rate during the co-digestion of rapeseed oil and sewage sludge in a CSTR--characterization of granules formed due to CaO addition to maintain process stability.

    PubMed

    Kasina, M; Kleyböcker, A; Michalik, M; Würdemann, H

    2015-01-01

    In a co-digestion system running with rapeseed oil and sewage sludge, an extremely fast increase in the organic loading rate was studied to develop a procedure to allow for flexible and demand-driven energy production. The over-acidification of the digestate was successfully prevented by calcium oxide dosage, which resulted in granule formation. Mineralogical analyses revealed that the granules were composed of insoluble salts of long chain fatty acids and calcium and had a porous structure. Long chain fatty acids and calcium formed the outer cover of granules and offered interfaces on the inside thereby enhancing the growth of biofilms. With granule size and age, the pore size increased and indicated degradation of granular interfaces. A stable biogas production up to the organic loading rate of 10.4 kg volatile solids m(-3) d(-1) was achieved although the hydrogen concentration was not favorable for propionic acid degradation. However, at higher organic loading rates, unbalanced granule formation and degradation were observed. Obviously, the adaption time for biofilm growth was too short to maintain the balance, thereby resulting in a low methane yield.

  16. Interactive and additive influences of Gender, BMI and Apolipoprotein 4 on cognition in children chronically exposed to high concentrations of PM2.5 and ozone. APOE 4 females are at highest risk in Mexico City.

    PubMed

    Calderón-Garcidueñas, Lilian; Jewells, Valerie; Galaz-Montoya, Carolina; van Zundert, Brigitte; Pérez-Calatayud, Angel; Ascencio-Ferrel, Eric; Valencia-Salazar, Gildardo; Sandoval-Cano, Marcela; Carlos, Esperanza; Solorio, Edelmira; Acuña-Ayala, Hilda; Torres-Jardón, Ricardo; D'Angiulli, Amedeo

    2016-10-01

    Children's air pollution exposures are associated with systemic and brain inflammation and the early hallmarks of Alzheimer's disease (AD). The Apolipoprotein E (APOE) 4 allele is the most prevalent genetic risk for AD, with higher risk for women. We assessed whether gender, BMI, APOE and metabolic variables in healthy children with high exposures to ozone and fine particulate matter (PM2.5) influence cognition. The Wechsler Intelligence Scale for Children (WISC-R) was administered to 105 Mexico City children (12.32±5.4 years, 69 APOE 3/3 and 36 APOE 3/4). APOE 4v 3 children showed decrements on attention and short-term memory subscales, and below-average scores in Verbal, Performance and Full Scale IQ. APOE 4 females had higher BMI and females with normal BMI between 75-94% percentiles had the highest deficits in Total IQ, Performance IQ, Digit Span, Picture Arrangement, Block Design and Object Assembly. Fasting glucose was significantly higher in APOE 4 children p=0.006, while Gender was the main variable accounting for the difference in insulin, HOMA-IR and leptin (p<.05). Gender, BMI and APOE influence children's cognitive responses to air pollution and glucose is likely a key player. APOE 4 heterozygous females with >75% to <94% BMI percentiles are at the highest risk of severe cognitive deficits (1.5-2SD from average IQ). Young female results highlight the urgent need for gender-targeted health programmes to improve cognitive responses. Multidisciplinary intervention strategies could provide paths for prevention or amelioration of female air pollution targeted cognitive deficits and possible long-term AD progression.

  17. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  18. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  19. Visual cognition

    SciTech Connect

    Pinker, S.

    1985-01-01

    This book consists of essays covering issues in visual cognition presenting experimental techniques from cognitive psychology, methods of modeling cognitive processes on computers from artificial intelligence, and methods of studying brain organization from neuropsychology. Topics considered include: parts of recognition; visual routines; upward direction; mental rotation, and discrimination of left and right turns in maps; individual differences in mental imagery, computational analysis and the neurological basis of mental imagery: componental analysis.

  20. COGNITIVE ECONOMICS.

    PubMed

    Kimball, Miles

    2015-06-01

    Cognitive economics is the economics of what is in people's minds. It is a vibrant area of research (much of it within behavioural economics, labour economics and the economics of education) that brings into play novel types of data, especially novel types of survey data. Such data highlight the importance of heterogeneity across individuals and highlight thorny issues for welfare economics. A key theme of cognitive economics is finite cognition (often misleadingly called "bounded rationality"), which poses theoretical challenges that call for versatile approaches. Cognitive economics brings a rich toolbox to the task of understanding a complex world.

  1. COGNITIVE ECONOMICS

    PubMed Central

    KIMBALL, MILES

    2017-01-01

    Cognitive economics is the economics of what is in people’s minds. It is a vibrant area of research (much of it within behavioural economics, labour economics and the economics of education) that brings into play novel types of data, especially novel types of survey data. Such data highlight the importance of heterogeneity across individuals and highlight thorny issues for welfare economics. A key theme of cognitive economics is finite cognition (often misleadingly called “bounded rationality”), which poses theoretical challenges that call for versatile approaches. Cognitive economics brings a rich toolbox to the task of understanding a complex world. PMID:28149186

  2. Cognitive decline in Parkinson disease.

    PubMed

    Aarsland, Dag; Creese, Byron; Politis, Marios; Chaudhuri, K Ray; Ffytche, Dominic H; Weintraub, Daniel; Ballard, Clive

    2017-04-01

    Dementia is a frequent problem encountered in advanced stages of Parkinson disease (PD). In recent years, research has focused on the pre-dementia stages of cognitive impairment in PD, including mild cognitive impairment (MCI). Several longitudinal studies have shown that MCI is a harbinger of dementia in PD, although the course is variable, and stabilization of cognition - or even reversal to normal cognition - is not uncommon. In addition to limbic and cortical spread of Lewy pathology, several other mechanisms are likely to contribute to cognitive decline in PD, and a variety of biomarker studies, some using novel structural and functional imaging techniques, have documented in vivo brain changes associated with cognitive impairment. The evidence consistently suggests that low cerebrospinal fluid levels of amyloid-β42, a marker of comorbid Alzheimer disease (AD), predict future cognitive decline and dementia in PD. Emerging genetic evidence indicates that in addition to the APOE*ε4 allele (an established risk factor for AD), GBA mutations and SCNA mutations and triplications are associated with cognitive decline in PD, whereas the findings are mixed for MAPT polymorphisms. Cognitive enhancing medications have some effect in PD dementia, but no convincing evidence that progression from MCI to dementia can be delayed or prevented is available, although cognitive training has shown promising results.

  3. Beyond perception: testing for implicit conceptual traces in high-load tasks.

    PubMed

    Ruz, María; Fuentes, Luis J

    2009-09-01

    The present commentary addresses the main results obtained in the Butler and Klein [Butler, B. C., & Klein, R. (2009). Inattentional blindness for ignored words: Comparison of explicit and implicit memory tasks. Consciousness and Cognition, 18, 811-819.] study and discusses them in relation to the Perceptual Load Theory of Lavie [Lavie, N. (1995). Perceptual load as a necessary condition for selective attention. Journal of Experimental Psychology: Human Perception and Performance, 21, 451-68.]. The authors claim that the use of implicit indexes of conceptual distractor processing in high-load situations would be an important addition to the load literature, which would benefit the research field regardless of their positive or negative findings.

  4. Soldier Cognitive Processes: Supporting Teleoperated Ground Vehicle Operations

    DTIC Science & Technology

    2014-12-01

    Performance Errors ...................................................8 Cognitive Load and Memory ...For example, skill-based errors (inadvertent errors due to attention and memory failures) are the most common type of error seen in most aviation...various subtasks so they have more resources available to address the novel aspects of each situation they encounter. Cognitive Load and Memory

  5. Cognitive Dimensions in Alzheimer’s Disease, Mild Cognitive Impairment, and Normal Elderly: Developing a Common Metric

    PubMed Central

    Chapman, Robert M.; Mapstone, Mark; McCrary, John W.; Gardner, Margaret N.; Bachus, Laura E.; DeGrush, Elizabeth; Reilly, Lindsey A.; Sandoval, Tiffany C.; Guillily, Maria D.

    2010-01-01

    The aim of this research was to assess similarity in cognitive factor structures underlying neuropsychological test performance of elders belonging to three clinical groups: Alzheimer’s disease (AD), Mild Cognitive Impairment (MCI), and normal elderly. We administered a battery of neuropsychological tests to 214 elderly participants in the groups. First, the underlying cognitive structure of a Combined-Set of AD, MCI, and Control subjects was determined by Principal Components Analysis (PCA), including quantitative relationships (loadings) between the test measures and the factors. The PCA resolved 17 neuropsychological test measures into 6 interpretable factors, accounting for 78% of the variance. This cognitive structure was compared with separate cognitive structures from an AD-Set, an MCI-Set, and a Control-Set (different individuals in each set) in additional PCA using Procrustes factor rotation. Analysis of congruence coefficients between each set and the Combined-Set by a bootstrapping statistical procedure supported the factor invariance hypothesis. These close similarities across groups in their underlying neuropsychological dimensions support the use of a common metric system (the factor structure of a Combined-Set) for measuring neuropsychological factors in all these elderly individuals. PMID:20717503

  6. LOADING DEVICE

    DOEpatents

    Ohlinger, L.A.

    1958-10-01

    A device is presented for loading or charging bodies of fissionable material into a reactor. This device consists of a car, mounted on tracks, into which the fissionable materials may be placed at a remote area, transported to the reactor, and inserted without danger to the operating personnel. The car has mounted on it a heavily shielded magazine for holding a number of the radioactive bodies. The magazine is of a U-shaped configuration and is inclined to the horizontal plane, with a cap covering the elevated open end, and a remotely operated plunger at the lower, closed end. After the fissionable bodies are loaded in the magazine and transported to the reactor, the plunger inserts the body at the lower end of the magazine into the reactor, then is withdrawn, thereby allowing gravity to roll the remaining bodies into position for successive loading in a similar manner.

  7. Harnessing the Wandering Mind: The Role of Perceptual Load

    ERIC Educational Resources Information Center

    Forster, Sophie; Lavie, Nilli

    2009-01-01

    Perceptual load is a key determinant of distraction by task-irrelevant stimuli (e.g., Lavie, N. (2005). "Distracted and confused?: Selective attention under load." "Trends in Cognitive Sciences," 9, 75-82). Here we establish the role of perceptual load in determining an internal form of distraction by task-unrelated thoughts (TUTs or…

  8. Cognitive Readiness

    DTIC Science & Technology

    2002-10-01

    II-4 C. Metacognition ...which requires cognitive mediation. • Metacognition . Metacognition refers to the executive functions of thought, particularly those pertaining to...knowledge and regulation of one’s cognitive processes and progress toward accepted goals. Metacognitive skills can be enhanced by exercises designed to

  9. Visual cognition

    SciTech Connect

    Pinker, S.

    1985-01-01

    This collection of research papers on visual cognition first appeared as a special issue of Cognition: International Journal of Cognitive Science. The study of visual cognition has seen enormous progress in the past decade, bringing important advances in our understanding of shape perception, visual imagery, and mental maps. Many of these discoveries are the result of converging investigations in different areas, such as cognitive and perceptual psychology, artificial intelligence, and neuropsychology. This volume is intended to highlight a sample of work at the cutting edge of this research area for the benefit of students and researchers in a variety of disciplines. The tutorial introduction that begins the volume is designed to help the nonspecialist reader bridge the gap between the contemporary research reported here and earlier textbook introductions or literature reviews.

  10. Primate cognition.

    PubMed

    Seed, Amanda; Tomasello, Michael

    2010-07-01

    As the cognitive revolution was slow to come to the study of animal behavior, the vast majority of what we know about primate cognition has been discovered in the last 30 years. Building on the recognition that the physical and social worlds of humans and their living primate relatives pose many of the same evolutionary challenges, programs of research have established that the most basic cognitive skills and mental representations that humans use to navigate those worlds are already possessed by other primates. There may be differences between humans and other primates, however, in more complex cognitive skills, such as reasoning about relations, causality, time, and other minds. Of special importance, the human primate seems to possess a species-unique set of adaptations for "cultural intelligence," which are broad reaching in their effects on human cognition.

  11. Carbohydrate Loading.

    ERIC Educational Resources Information Center

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  12. Understanding the Effects of Databases as Cognitive Tools in a Problem-Based Multimedia Learning Environment

    ERIC Educational Resources Information Center

    Li, Rui; Liu, Min

    2007-01-01

    The purpose of this study is to examine the potential of using computer databases as cognitive tools to share learners' cognitive load and facilitate learning in a multimedia problem-based learning (PBL) environment designed for sixth graders. Two research questions were: (a) can the computer database tool share sixth-graders' cognitive load? and…

  13. Cognitive Performance and Cognitive Style.

    ERIC Educational Resources Information Center

    International Journal of Behavioral Development, 1985

    1985-01-01

    Investigates (1) the relationships between cognitive performance and cognitive styles and predictive possibilities and (2) performance differences by sex, school, grade, and income in 92 Indian adolescents. Assessment measures included Liquid Conservation, Islands, Goat-Lion, Hanoi-Tower, Rabbits (Piagetian); Block Design (WISC-R); Paper Cutting…

  14. Characterization of cognitive and motor performance during dual-tasking in healthy older adults and patients with Parkinson's disease.

    PubMed

    Wild, Lucia Bartmann; de Lima, Daiane Borba; Balardin, Joana Bisol; Rizzi, Luana; Giacobbo, Bruno Lima; Oliveira, Henrique Bianchi; de Lima Argimon, Irani Iracema; Peyré-Tartaruga, Leonardo Alexandre; Rieder, Carlos R M; Bromberg, Elke

    2013-02-01

    The primary purpose of this study was to investigate the effect of dual-tasking on cognitive performance and gait parameters in patients with idiopathic Parkinson's disease (PD) without dementia. The impact of cognitive task complexity on cognition and walking was also examined. Eighteen patients with PD (ages 53-88, 10 women; Hoehn and Yahr stage I-II) and 18 older adults (ages 61-84; 10 women) completed two neuropsychological measures of executive function/attention (the Stroop Test and Wisconsin Card Sorting Test). Cognitive performance and gait parameters related to functional mobility of stride were measured under single (cognitive task only) and dual-task (cognitive task during walking) conditions with different levels of difficulty and different types of stimuli. In addition, dual-task cognitive costs were calculated. Although cognitive performance showed no significant difference between controls and PD patients during single or dual-tasking conditions, only the patients had a decrease in cognitive performance during walking. Gait parameters of patients differed significantly from controls at single and dual-task conditions, indicating that patients gave priority to gait while cognitive performance suffered. Dual-task cognitive costs of patients increased with task complexity, reaching significantly higher values then controls in the arithmetic task, which was correlated with scores on executive function/attention (Stroop Color-Word Page). Baseline motor functioning and task executive/attentional load affect the performance of cognitive tasks of PD patients while walking. These findings provide insight into the functional strategies used by PD patients in the initial phases of the disease to manage dual-task interference.

  15. Cognitive anthropology is a cognitive science.

    PubMed

    Boster, James S

    2012-07-01

    Cognitive anthropology contributes to cognitive science as a complement to cognitive psychology. The chief threat to its survival has not been rejection by other cognitive scientists but by other cultural anthropologists. It will remain a part of cognitive science as long as cognitive anthropologists research, teach, and publish.

  16. A Model of Auditory-Cognitive Processing and Relevance to Clinical Applicability.

    PubMed

    Edwards, Brent

    2016-01-01

    Hearing loss and cognitive function interact in both a bottom-up and top-down relationship. Listening effort is tied to these interactions, and models have been developed to explain their relationship. The Ease of Language Understanding model in particular has gained considerable attention in its explanation of the effect of signal distortion on speech understanding. Signal distortion can also affect auditory scene analysis ability, however, resulting in a distorted auditory scene that can affect cognitive function, listening effort, and the allocation of cognitive resources. These effects are explained through an addition to the Ease of Language Understanding model. This model can be generalized to apply to all sounds, not only speech, representing the increased effort required for auditory environmental awareness and other nonspeech auditory tasks. While the authors have measures of speech understanding and cognitive load to quantify these interactions, they are lacking measures of the effect of hearing aid technology on auditory scene analysis ability and how effort and attention varies with the quality of an auditory scene. Additionally, the clinical relevance of hearing aid technology on cognitive function and the application of cognitive measures in hearing aid fittings will be limited until effectiveness is demonstrated in real-world situations.

  17. Cognitive Predictors of Rapid Picture Naming

    ERIC Educational Resources Information Center

    Decker, Scott L.; Roberts, Alycia M.; Englund, Julia A.

    2013-01-01

    Deficits in rapid automatized naming (RAN) have been found to be a sensitive cognitive marker for children with dyslexia. However, there is a lack of consensus regarding the construct validity and theoretical neuro-cognitive processes involved in RAN. Additionally, most studies investigating RAN include a narrow range of cognitive measures. The…

  18. LOADED WAVEGUIDES

    DOEpatents

    Mullett, L.B.; Loach, B.G.; Adams, G.L.

    1958-06-24

    >Loaded waveguides are described for the propagation of electromagnetic waves with reduced phase velocities. A rectangular waveguide is dimensioned so as to cut-off the simple H/sub 01/ mode at the operating frequency. The waveguide is capacitance loaded, so as to reduce the phase velocity of the transmitted wave, by connecting an electrical conductor between directly opposite points in the major median plane on the narrower pair of waveguide walls. This conductor may take a corrugated shape or be an aperature member, the important factor being that the electrical length of the conductor is greater than one-half wavelength at the operating frequency. Prepared for the Second U.N. International ConferThe importance of nuclear standards is duscussed. A brief review of the international callaboration in this field is given. The proposal is made to let the International Organization for Standardization (ISO) coordinate the efforts from other groups. (W.D.M.)

  19. Cognitive Function

    EPA Science Inventory

    Because chemicals can adversely affect cognitive function in humans, considerable effort has been made to characterize their effects using animal models. Information from such models will be necessary to: evaluate whether chemicals identified as potentially neurotoxic by screenin...

  20. Cognitive Changes

    MedlinePlus

    ... Are the Alternative Treatments for Cognitive Problems? Anxiety Hallucinations/Delusions Speech and Swallowing Problems Vision Changes You ... and the Hope for a Better Drug for Hallucinations and Psychosis in Parkinson’s Disease What's Hot in ...

  1. Spatial cognition

    NASA Technical Reports Server (NTRS)

    Kaiser, Mary Kister; Remington, Roger

    1988-01-01

    Spatial cognition is the ability to reason about geometric relationships in the real (or a metaphorical) world based on one or more internal representations of those relationships. The study of spatial cognition is concerned with the representation of spatial knowledge, and our ability to manipulate these representations to solve spatial problems. Spatial cognition is utilized most critically when direct perceptual cues are absent or impoverished. Examples are provided of how human spatial cognitive abilities impact on three areas of space station operator performance: orientation, path planning, and data base management. A videotape provides demonstrations of relevant phenomena (e.g., the importance of orientation for recognition of complex, configural forms). The presentation is represented by abstract and overhead visuals only.

  2. Truck loading rack blending

    SciTech Connect

    Boubenider, E.

    1995-12-01

    Blending, the combining of two or more components to make a single product, has become widely used in most loading rack applications. Blending should not be confused with additive injection, which is the injection of very small doses of enhancers, detergents and dyes into a product stream. Changes in the environmental protection laws in the early 90`s have put increasing demands on marketing terminals with regards to reformulated fuels and environmental protection concerns. As a result of these new mandates, terminals have turned to blending at the loading rack as an economical and convenient means in meeting these new requirements. This paper will discuss some of these mandates and how loading rack blending is used for different applications. Various types of blending will also be discussed along with considerations for each method.

  3. COGNITIVE PROFILE OF TURNER SYNDROME

    PubMed Central

    Hong, David; Kent, Jamie Scaletta; Kesler, Shelli

    2011-01-01

    Turner syndrome (TS) is a relatively common neurogenetic disorder characterized by complete or partial monosomy-X in a phenotypic female. TS is associated with a cognitive profile that typically includes intact intellectual function and verbal abilities with relative weaknesses in visual–spatial, executive, and social cognitive domains. In this report, we review previous and current research related to the cognitive profile of TS. We also discuss how cognitive impairments in this syndrome may reflect integrative rather than modular deficits. For example, the less commonly reported areas of verbal difficulty in TS and certain visual–spatial deficits seem significantly influenced by impairments in executive function and spatially loaded stimuli. We provide a summary of cognitive testing measures used in the assessment of visual–spatial and executive skills, which includes test domain descriptions as well as a comprehensive examination of social cognitive function in TS. This review concludes with a discussion of ecological interpretations regarding the meaning of cognitive deficits in TS at the individual level. PMID:20014362

  4. Disembodying cognition

    PubMed Central

    Chatterjee, Anjan

    2010-01-01

    The idea that concepts are embodied by our motor and sensory systems is popular in current theorizing about cognition. Embodied cognition accounts come in different versions and are often contrasted with a purely symbolic amodal view of cognition. Simulation, or the hypothesis that concepts simulate the sensory and motor experience of real world encounters with instances of those concepts, has been prominent in psychology and cognitive neuroscience. Here, with a focus on spatial thought and language, I review some of the evidence cited in support of simulation versions of embodied cognition accounts. While these data are extremely interesting and many of the experiments are elegant, knowing how to best interpret the results is often far from clear. I point out that a quick acceptance of embodied accounts runs the danger of ignoring alternate hypotheses and not scrutinizing neuroscience data critically. I also review recent work from my lab that raises questions about the nature of sensory motor grounding in spatial thought and language. In my view, the question of whether or not cognition is grounded is more fruitfully replaced by questions about gradations in this grounding. A focus on disembodying cognition, or on graded grounding, opens the way to think about how humans abstract. Within neuroscience, I propose that three functional anatomic axes help frame questions about the graded nature of grounded cognition. First, are questions of laterality differences. Do association cortices in both hemispheres instantiate the same kind of sensory or motor information? Second, are questions about ventral dorsal axes. Do neuronal ensembles along this axis shift from conceptual representations of objects to the relationships between objects? Third, are questions about gradients centripetally from sensory and motor cortices towards and within perisylvian cortices. How does sensory and perceptual information become more language-like and then get transformed into language

  5. Cognitive fatigue: A Time-based Resource-sharing account.

    PubMed

    Borragán, Guillermo; Slama, Hichem; Bartolomei, Mario; Peigneux, Philippe

    2017-04-01

    Cognitive Fatigue (CF) is an important confound impacting cognitive performance. How CF is triggered and what are the features that make a cognitive effort perceived as exhausting remain unclear. In the theoretical framework of the Time-based Resource-sharing (TBRS) model (Barrouillet et al., 2004), we hypothesized that CF is an outcome of increased cognitive load due to constrained time to process ongoing cognitive demands. We tested this cognitive load-related CF hypothesis across 2 experiments manipulating both task complexity and cognitive load induced by the processing time interval. To do so, we used the TloadDback paradigm, a working memory dual task in which high and low cognitive load levels can be individually adjusted. In Experiment 1, participants were administered a high cognitive load (HCL, short processing time interval) and a low cognitive load (LCL, large processing time interval) conditions while complexity of the task was kept constant (1-back dual task). In Experiment 2, two tasks featuring different levels of complexity were both administered at the individual's maximal processing speed capacity for each task (i.e., short processing time interval). Results disclosed higher CF in the HCL than in the LCL condition in Experiment 1. On the contrary, in Experiment 2 similar levels of CF were obtained for different levels of task complexity when processing time interval was individually adjusted to induce a HCL condition. Altogether, our results indicate that processing time-related cognitive load eventually leads to the subjective feeling of CF, and to a decrease in alertness. In this framework, we propose that the development of CF can be envisioned as the result of sustained cognitive demands irrespective of task complexity.

  6. Cognitive Penetration and Attention

    PubMed Central

    Gross, Steven

    2017-01-01

    Zenon Pylyshyn argues that cognitively driven attentional effects do not amount to cognitive penetration of early vision because such effects occur either before or after early vision. Critics object that in fact such effects occur at all levels of perceptual processing. We argue that Pylyshyn’s claim is correct—but not for the reason he emphasizes. Even if his critics are correct that attentional effects are not external to early vision, these effects do not satisfy Pylyshyn’s requirements that the effects be direct and exhibit semantic coherence. In addition, we distinguish our defense from those found in recent work by Raftopoulos and by Firestone and Scholl, argue that attention should not be assimilated to expectation, and discuss alternative characterizations of cognitive penetrability, advocating a kind of pluralism. PMID:28275358

  7. Distracted and confused?: selective attention under load.

    PubMed

    Lavie, Nilli

    2005-02-01

    The ability to remain focused on goal-relevant stimuli in the presence of potentially interfering distractors is crucial for any coherent cognitive function. However, simply instructing people to ignore goal-irrelevant stimuli is not sufficient for preventing their processing. Recent research reveals that distractor processing depends critically on the level and type of load involved in the processing of goal-relevant information. Whereas high perceptual load can eliminate distractor processing, high load on "frontal" cognitive control processes increases distractor processing. These findings provide a resolution to the long-standing early and late selection debate within a load theory of attention that accommodates behavioural and neuroimaging data within a framework that integrates attention research with executive function.

  8. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  9. Visual cognition

    PubMed Central

    Cavanagh, Patrick

    2011-01-01

    Visual cognition, high-level vision, mid-level vision and top-down processing all refer to decision-based scene analyses that combine prior knowledge with retinal input to generate representations. The label “visual cognition” is little used at present, but research and experiments on mid- and high-level, inference-based vision have flourished, becoming in the 21st century a significant, if often understated part, of current vision research. How does visual cognition work? What are its moving parts? This paper reviews the origins and architecture of visual cognition and briefly describes some work in the areas of routines, attention, surfaces, objects, and events (motion, causality, and agency). Most vision scientists avoid being too explicit when presenting concepts about visual cognition, having learned that explicit models invite easy criticism. What we see in the literature is ample evidence for visual cognition, but few or only cautious attempts to detail how it might work. This is the great unfinished business of vision research: at some point we will be done with characterizing how the visual system measures the world and we will have to return to the question of how vision constructs models of objects, surfaces, scenes, and events. PMID:21329719

  10. Cognitive linguistics.

    PubMed

    Evans, Vyvyan

    2012-03-01

    Cognitive linguistics is one of the fastest growing and influential perspectives on the nature of language, the mind, and their relationship with sociophysical (embodied) experience. It is a broad theoretical and methodological enterprise, rather than a single, closely articulated theory. Its primary commitments are outlined. These are the Cognitive Commitment-a commitment to providing a characterization of language that accords with what is known about the mind and brain from other disciplines-and the Generalization Commitment-which represents a dedication to characterizing general principles that apply to all aspects of human language. The article also outlines the assumptions and worldview which arises from these commitments, as represented in the work of leading cognitive linguists. WIREs Cogn Sci 2012, 3:129-141. doi: 10.1002/wcs.1163 For further resources related to this article, please visit the WIREs website.

  11. PERFORMANCE OF A COMPUTER-BASED ASSESSMENT OF COGNITIVE FUNCTION MEASURES IN TWO COHORTS OF SENIORS

    PubMed Central

    Espeland, Mark A.; Katula, Jeffrey A.; Rushing, Julia; Kramer, Arthur F.; Jennings, Janine M.; Sink, Kaycee M.; Nadkarni, Neelesh K.; Reid, Kieran F.; Castro, Cynthia M.; Church, Timothy; Kerwin, Diana R.; Williamson, Jeff D.; Marottoli, Richard A.; Rushing, Scott; Marsiske, Michael; Rapp, Stephen R.

    2013-01-01

    Background Computer-administered assessment of cognitive function is being increasingly incorporated in clinical trials, however its performance in these settings has not been systematically evaluated. Design The Seniors Health and Activity Research Program (SHARP) pilot trial (N=73) developed a computer-based tool for assessing memory performance and executive functioning. The Lifestyle Interventions and Independence for Seniors (LIFE) investigators incorporated this battery in a full scale multicenter clinical trial (N=1635). We describe relationships that test scores have with those from interviewer-administered cognitive function tests and risk factors for cognitive deficits and describe performance measures (completeness, intra-class correlations). Results Computer-based assessments of cognitive function had consistent relationships across the pilot and full scale trial cohorts with interviewer-administered assessments of cognitive function, age, and a measure of physical function. In the LIFE cohort, their external validity was further demonstrated by associations with other risk factors for cognitive dysfunction: education, hypertension, diabetes, and physical function. Acceptable levels of data completeness (>83%) were achieved on all computer-based measures, however rates of missing data were higher among older participants (odds ratio=1.06 for each additional year; p<0.001) and those who reported no current computer use (odds ratio=2.71; p<0.001). Intra-class correlations among clinics were at least as low (ICC≤0.013) as for interviewer measures (ICC≤0.023), reflecting good standardization. All cognitive measures loaded onto the first principal component (global cognitive function), which accounted for 40% of the overall variance. Conclusion Our results support the use of computer-based tools for assessing cognitive function in multicenter clinical trials of older individuals. PMID:23589390

  12. Cognitive fitness.

    PubMed

    Gilkey, Roderick; Kilts, Clint

    2007-11-01

    Recent neuroscientific research shows that the health of your brain isn't, as experts once thought, just the product of childhood experiences and genetics; it reflects your adult choices and experiences as well. Professors Gilkey and Kilts of Emory University's medical and business schools explain how you can strengthen your brain's anatomy, neural networks, and cognitive abilities, and prevent functions such as memory from deteriorating as you age. The brain's alertness is the result of what the authors call cognitive fitness -a state of optimized ability to reason, remember, learn, plan, and adapt. Certain attitudes, lifestyle choices, and exercises enhance cognitive fitness. Mental workouts are the key. Brain-imaging studies indicate that acquiring expertise in areas as diverse as playing a cello, juggling, speaking a foreign language, and driving a taxicab expands your neural systems and makes them more communicative. In other words, you can alter the physical makeup of your brain by learning new skills. The more cognitively fit you are, the better equipped you are to make decisions, solve problems, and deal with stress and change. Cognitive fitness will help you be more open to new ideas and alternative perspectives. It will give you the capacity to change your behavior and realize your goals. You can delay senescence for years and even enjoy a second career. Drawing from the rapidly expanding body of neuroscience research as well as from well-established research in psychology and other mental health fields, the authors have identified four steps you can take to become cognitively fit: understand how experience makes the brain grow, work hard at play, search for patterns, and seek novelty and innovation. Together these steps capture some of the key opportunities for maintaining an engaged, creative brain.

  13. Translation Meets Cognitive Science: The Imprint of Translation on Cognitive Processing

    ERIC Educational Resources Information Center

    Rojo, Ana

    2015-01-01

    Translation has long played a role in linguistic and literary studies research. More recently, the theoretical and methodological concerns of process research have given translation an additional role in cognitive science. The interest in the cognitive aspects of translation has led scholars to turn to disciplines such as cognitive linguistics,…

  14. Baby Carriage: Infants Walking with Loads

    ERIC Educational Resources Information Center

    Garciaguirre, Jessie S.; Adolph, Karen E.; Shrout, Patrick E.

    2007-01-01

    Maintaining balance is a central problem for new walkers. To examine how infants cope with the additional balance control problems induced by load carriage, 14-month-olds were loaded with 15% of their body weight in shoulder-packs. Both symmetrical and asymmetrical loads disrupted alternating gait patterns and caused less mature footfall patterns.…

  15. Cognitive Science.

    ERIC Educational Resources Information Center

    Soni, P. Sarita, Ed.; Carmichael, Ann G., Ed.

    1993-01-01

    This theme issue features five articles profiling Indiana University faculty whose work on various campuses continues to broaden and advance knowledge about cognitive science. The articles in the journal are: "A Matter of Time" (Karen Grooms) which discusses the work of Robert F. Port; "Perceiving as a Complex System" (Tom…

  16. Cognitive Science.

    ERIC Educational Resources Information Center

    Cocking, Rodney R.; Mestre, Jose P.

    The focus of this paper is on cognitive science as a model for understanding the application of human skills toward effective problem-solving. Sections include: (1) "Introduction" (discussing information processing framework, expert-novice distinctions, schema theory, and learning process); (2) "Application: The Expert-Novice…

  17. Cognitive Challenges

    MedlinePlus

    ... Custom Post Type Home En Español International Request Information DONATE About TSC New treatments today. A cure tomorrow. What is TSC? How is ... questions on intellectual disability. Disabled World — Cognitive disability: information on intellectual disabilities. Healthy ... Also in this Section What is TSC? How ...

  18. Diabetes mellitus and cognitive impairments

    PubMed Central

    Saedi, Elham; Gheini, Mohammad Reza; Faiz, Firoozeh; Arami, Mohammad Ali

    2016-01-01

    There is strong evidence that diabetes mellitus increases the risk of cognitive impairment and dementia. Insulin signaling dysregulation and small vessel disease in the base of diabetes may be important contributing factors in Alzheimer’s disease and vascular dementia pathogenesis, respectively. Optimal glycemic control in type 1 diabetes and identification of diabetic risk factors and prophylactic approach in type 2 diabetes are very important in the prevention of cognitive complications. In addition, hypoglycemic attacks in children and elderly should be avoided. Anti-diabetic medications especially Insulin may have a role in the management of cognitive dysfunction and dementia but further investigation is needed to validate these findings. PMID:27660698

  19. Prevention of cognitive deficits and brain oxidative stress with superoxide dismutase/catalase mimetics in aged mice.

    PubMed

    Clausen, Aaron; Doctrow, Susan; Baudry, Michel

    2010-03-01

    Continuous decline in cognitive performance accompanies the natural aging process in humans, and multiple studies in both humans and animal models have indicated that this decrease in cognitive function is associated with an age-related increase in oxidative stress. Treating aging mammals with exogenous free radical scavengers has generally been shown to attenuate age-related cognitive decline and oxidative stress. The present study assessed the effectiveness of the superoxide dismutase/catalase mimetics EUK-189 and EUK-207 on age-related decline in cognitive function and increase in oxidative stress. C57/BL6 mice received continuous treatment via osmotic minipumps with either EUK-189 or EUK-207 for 6 months starting at 17 months of age. At the end of treatment, markers for oxidative stress were evaluated by analyzing levels of free radicals, lipid peroxidation and oxidized nucleic acids in brain tissue. In addition, cognitive performance was assessed after 3 and 6 months of treatment with fear conditioning. Both EUK-189 and EUK-207 treatments resulted in significantly decreased lipid peroxidation, nucleic acid oxidation, and reactive oxygen species (ROS) levels. In addition, the treatments also significantly improved age-related decline in performance in the fear-conditioning task. Our results thus confirm a critical role for oxidative stress in age-related decline in learning and memory and strongly suggest a potential usefulness for salen-manganese complexes in reversing age-related declines in cognitive function and oxidative load.

  20. Potential of Cognitive Computing and Cognitive Systems

    NASA Astrophysics Data System (ADS)

    Noor, Ahmed K.

    2014-11-01

    Cognitive computing and cognitive technologies are game changers for future engineering systems, as well as for engineering practice and training. They are major drivers for knowledge automation work, and the creation of cognitive products with higher levels of intelligence than current smart products. This paper gives a brief review of cognitive computing and some of the cognitive engineering systems activities. The potential of cognitive technologies is outlined, along with a brief description of future cognitive environments, incorporating cognitive assistants - specialized proactive intelligent software agents designed to follow and interact with humans and other cognitive assistants across the environments. The cognitive assistants engage, individually or collectively, with humans through a combination of adaptive multimodal interfaces, and advanced visualization and navigation techniques. The realization of future cognitive environments requires the development of a cognitive innovation ecosystem for the engineering workforce. The continuously expanding major components of the ecosystem include integrated knowledge discovery and exploitation facilities (incorporating predictive and prescriptive big data analytics); novel cognitive modeling and visual simulation facilities; cognitive multimodal interfaces; and cognitive mobile and wearable devices. The ecosystem will provide timely, engaging, personalized / collaborative, learning and effective decision making. It will stimulate creativity and innovation, and prepare the participants to work in future cognitive enterprises and develop new cognitive products of increasing complexity. http://www.aee.odu.edu/cognitivecomp

  1. Effects of Increasing Task Load on Memory Impairment in Adults with Down Syndrome

    ERIC Educational Resources Information Center

    Oliver, Chris; Holland, Tony; Hall, Scott; Crayton, Lissa

    2005-01-01

    The effect of increasing the number of stimuli to be recalled was investigated to evaluate whether sensitivity for memory impairment was enhanced in adults with Down syndrome when using higher task load. Three levels of load were compared across three groups of adults: those with cognitive deterioration, no cognitive deterioration over age 40, and…

  2. Multifunctional lubricant additives and compositions thereof

    SciTech Connect

    Farng, L.O.; Horodysky, A.G.

    1991-03-26

    This paper discusses an antioxidant/ antiwear/extreme pressure/load carrying lubricant composition. It comprises a major proportion of an oil of lubricating viscosity or grease or other solid lubricant prepared therefrom and a minor amount of an ashless multifunctional antioxidant/antiwear/extreme pressure/load carrying additive product comprising a thiophosphate derived from a dihydrocarbyl dithiocarbamate.

  3. National Launch System cycle 1 loads and models data book

    NASA Technical Reports Server (NTRS)

    Bugg, F.; Brunty, J.; Ernsberger, G.; Mcghee, D.; Gagliano, L.; Harrington, F.; Meyer, D.; Blades, E.

    1992-01-01

    This document contains preliminary cycle 1 loads for the National Launch System (NLS) 1 and 2 vehicles. The loads provided and recommended as design loads represent the maximum load expected during prelaunch and flight regimes, i.e., limit loads, except that propellant tank ullage pressure has not been included. Ullage pressure should be added to the loads book values for cases where the addition results in higher loads. The loads must be multiplied by the appropriate factors of safety to determine the ultimate loads for which the structure must be capable.

  4. Cognitive Astrophysics

    NASA Astrophysics Data System (ADS)

    Madore, Barry F.

    2012-09-01

    Cognitive Astrophysics works at the cusp between Cognitive Science and Astrophysics, drawing upon lessons learned in the Philosophy of Science, Linguistics and Artificial Intelligence. We will introduce and illustrate the concept of ``Downward Causation,'' common in philosophical discussions, but either unknown to or disdained by most physicists. A clear example operating on cosmological scales involving the origin of large-scale structure will be given. We will also make the case that on scales exceeding most laboratory experiments, self-gravitating matter can be considered to be in a ``fifth state'', characterized primarily by its negative specific heat, as first recognized by Lynden-Bell and Lynden-Bell (1977, MNRAS, 181, 405). Such systems increase their temperature as they lose energy. Numerous examples will be given and discussed.

  5. Explicit Instructions Increase Cognitive Costs of Deception in Predictable Social Context

    PubMed Central

    Falkiewicz, Marcel; Sarzyńska, Justyna; Babula, Justyna; Szatkowska, Iwona; Grabowska, Anna; Nęcka, Edward

    2015-01-01

    Convincing participants to deceive remains one of the biggest and most important challenges of laboratory-based deception research. The simplest and most prevalent method involves explicitly instructing participants to lie or tell the truth before presenting each task item. The usual finding of such experiments is increased cognitive load associated with deceptive responses, explained by necessity to inhibit default and automatic honest responses. However, explicit instructions are usually coupled with the absence of social context in the experimental task. Context plays a key role in social cognition by activating prior knowledge, which facilitates behaviors consistent with the latter. We hypothesized that in the presence of social context, both honest and deceptive responses can be produced on the basis of prior knowledge, without reliance on truth and without additional cognitive load during deceptive responses. In order to test the hypothesis, we have developed Speed-Dating Task (SDT), which is based on a real-life social event. In SDT, participants respond both honestly and deceptively to questions in order to appear similar to each of the dates. The dates are predictable and represent well-known categories (i.e., atheist or conservative). In one condition participants rely on explicit instructions preceding each question (external cue). In the second condition no explicit instructions are present, so the participants need to adapt based on prior knowledge about the category the dates belong to (internal cue). With internal cues, reaction times (RTs) are similar for both honest and deceptive responses. However, in the presence of external cues (EC), RTs are longer for deceptive than honest responses, suggesting that deceptive responses are associated with increased cognitive load. Compared to internal cues, deception costs were higher when EC were present. However, the effect was limited to the first part of the experiment, only partially confirming our

  6. Can cognitive science create a cognitive economics?

    PubMed

    Chater, Nick

    2015-02-01

    Cognitive science can intersect with economics in at least three productive ways: by providing richer models of individual behaviour for use in economic analysis; by drawing from economic theory in order to model distributed cognition; and jointly to create more powerful 'rational' models of cognitive processes and social interaction. There is the prospect of moving from behavioural economics to a genuinely cognitive economics.

  7. Sandia Cognitive Runtime Engine with Active Memory

    SciTech Connect

    Xavier, Patrick; Chen, Michael C.; Hart, Brian; Hart, Derek; Lippitt, Carl; Wolfenbarger, Paul; Waymire, Russel

    2005-12-01

    The SCREAM (Sandia Cognitive Runtime Engine with Active memory) software implements a subset of a Cognitive Famework developed at Sandia National Laboratories. The software is implemented in the Umbra simulation and modular software framework, which is C++-based. SCREAM components include a Concept Instance Driver, Semantic Activation Network, Concept Database, Context Recognizer, Context Database, Episodic Memory, Egocentric Spatial Memory, Allocentric Spatial Memory, Comparator, and a Context to Abstract Action converter. At initialization, modules load the data files that together specify all the components of a particular cognitive model, such as concept declarations, context declarations, spreading activation weights, and context/situation-cue-patterns.

  8. Cognitive Analysis of Decision Support for Antibiotic Ordering in a Neonatal Intensive Care Unit

    PubMed Central

    Sheehan, B.; Kaufman, D.; Bakken, S.; Currie, L. M.

    2012-01-01

    Background Clinical decision support systems (CDSS) are a method used to support prescribing accuracy when deployed within a computerized provider order entry system (CPOE). Divergence from using CDSS is exemplified by high alert override rates. Excessive cognitive load imposed by the CDSS may help to explain such high rates. Objectives: The aim of this study was to describe the cognitive impact of a CPOE-integrated CDSS by categorizing system use problems according to the type of mental processing required to resolve them. Methods A qualitative, descriptive design was used employing two methods; a cognitive walkthrough and a think-aloud protocol. Data analysis was guided by Norman’s Theory of Action and a theory of cognitive distances which is an extension to Norman’s theory. Results The most frequently occurring source of excess cognitive effort was poor information timing. Information presented by the CDSS was often presented after clinicians required the information for decision making. Additional sources of effort included use of language that was not clear to the user, vague icons, and lack of cues to guide users through tasks. Conclusions Lack of coordination between clinician’s task-related thought processes and those presented by a CDSS results in excessive cognitive work required to use the system. This can lead to alert overrides and user errors. Close attention to user’s cognitive processes as they carry out clinical tasks prior to CDSS development may provide key information for system design that supports clinical tasks and reduces cognitive effort. PMID:23616903

  9. Postmenopausal hormone therapy and cognition.

    PubMed

    McCarrey, Anna C; Resnick, Susan M

    2015-08-01

    This article is part of a Special Issue "Estradiol and cognition". Prior to the publication of findings from the Women's Health Initiative (WHI) in 2002, estrogen-containing hormone therapy (HT) was used to prevent age-related disease, especially cardiovascular disease, and to treat menopausal symptoms such as hot flushes and sleep disruptions. Some observational studies of HT in midlife and aging women suggested that HT might also benefit cognitive function, but randomized clinical trials have produced mixed findings in terms of health and cognitive outcomes. This review focuses on hormone effects on cognition and risk for dementia in naturally menopausal women as well as surgically induced menopause, and highlights findings from the large-scale WHI Memory Study (WHIMS) which, contrary to expectation, showed increased dementia risk and poorer cognitive outcomes in older postmenopausal women randomized to HT versus placebo. We consider the 'critical window hypothesis', which suggests that a window of opportunity may exist shortly after menopause during which estrogen treatments are most effective. In addition, we highlight emerging evidence that potential adverse effects of HT on cognition are most pronounced in women who have other health risks, such as lower global cognition or diabetes. Lastly, we point towards implications for future research and clinical treatments.

  10. Neuro-ergonomic Research for Online Assessment of Cognitive Workload

    DTIC Science & Technology

    2011-10-01

    capacity and duration . These limitations will, under some conditions, hold back people’s learning, and performance. Underloading or overloading of cognitive...fluctuations of instantaneous cognitive load. Eye movement (blink rate/latency/ duration ) have shown to have a weak relation to cogni- tive load. However...working memory. As a matter of fact, working memory is limited in both capacity and duration , and these limitations will, under some circumstances

  11. The Role of Cognitive Control in Older Adult Cognitive Reappraisal: Detached and Positive Reappraisal

    PubMed Central

    Liang, Ying; Huo, Meng; Kennison, Robert; Zhou, Renlai

    2017-01-01

    Older adults are more likely to regulate their emotions by engaging in cognitive reappraisal. However, depending on the type of cognitive reappraisal used, efforts to regulate emotions are sometimes met with success and other times with failure. It has been suggested the well-known age-related decline in cognitive control might be the culprit behind the poor use of detached reappraisal by older adults. However, this possibility has not been thoroughly investigated. In addition, studies have not examined what aspects of cognitive control– shifting, updating or inhibition–might be relevant to cognitive reappraisal. In the present study, 41 older participants were tested on cognitive control and abilities to use detached and positive reappraisal. Results showed detached reappraisal compared to positive relied more heavily on cognitive control, specifically mental set shifting. Results of this study have important implications for development of cognitive training interventions for older adults. PMID:28326024

  12. The Role of Cognitive Control in Older Adult Cognitive Reappraisal: Detached and Positive Reappraisal.

    PubMed

    Liang, Ying; Huo, Meng; Kennison, Robert; Zhou, Renlai

    2017-01-01

    Older adults are more likely to regulate their emotions by engaging in cognitive reappraisal. However, depending on the type of cognitive reappraisal used, efforts to regulate emotions are sometimes met with success and other times with failure. It has been suggested the well-known age-related decline in cognitive control might be the culprit behind the poor use of detached reappraisal by older adults. However, this possibility has not been thoroughly investigated. In addition, studies have not examined what aspects of cognitive control- shifting, updating or inhibition-might be relevant to cognitive reappraisal. In the present study, 41 older participants were tested on cognitive control and abilities to use detached and positive reappraisal. Results showed detached reappraisal compared to positive relied more heavily on cognitive control, specifically mental set shifting. Results of this study have important implications for development of cognitive training interventions for older adults.

  13. Walking with a Backpack using Load Distribution and Dynamic Load Compensation Reduces Metabolic Cost and Adaptations to Loads.

    PubMed

    Park, Joon-Hyuk; Stegall, Paul; Zhang, Haohan; Agrawal, Sunil

    2016-11-09

    In this study, we showed a way of reducing the metabolic cost of walking with a backpack using load distribution and dynamic load compensation, provided by a wearable upper body device. This device distributes the backpack load between the shoulders and the pelvis, senses the vertical motion of the pelvis, and provides gait synchronized compensatory forces to reduce the dynamic loads from a backpack. It was hypothesized that by reducing dynamic loads from a backpack during load carriage, the users gait and postural adaptation, muscular effort and metabolic cost would be reduced. This hypothesis was supported by biomechanical and physiological measurements on a group of young healthy subjects, as they walked on a treadmill under 4 different conditions: unloaded; with a backpack, loaded with 25% of their body weight, supported on the shoulders; with the same load distributed between the shoulders and the pelvis; and with dynamic load compensation in addition to load distribution. The results showed reductions in gait and postural adaptations, muscle activity, vertical and braking ground reaction forces, and metabolic cost while carrying the same backpack load with the device. We conclude that the device can potentially reduce the risk of musculoskeletal injuries and muscle fatigue associated with carrying heavy backpack loads while reducing the metabolic cost of loaded walking.

  14. Multidimensional spectral load balancing

    SciTech Connect

    Hendrickson, B.; Leland, R.

    1993-01-01

    We describe an algorithm for the static load balancing of scientific computations that generalizes and improves upon spectral bisection. Through a novel use of multiple eigenvectors, our new spectral algorithm can divide a computation into 4 or 8 pieces at once. These multidimensional spectral partitioning algorithms generate balanced partitions that have lower communication overhead and are less expensive to compute than those produced by spectral bisection. In addition, they automatically work to minimize message contention on a hypercube or mesh architecture. These spectral partitions are further improved by a multidimensional generalization of the Kernighan-Lin graph partitioning algorithm. Results on several computational grids are given and compared with other popular methods.

  15. Microbial Load Monitor

    NASA Technical Reports Server (NTRS)

    Gibson, S. F.; Royer, E. R.

    1979-01-01

    The Microbial Load Monitor (MLM) is an automated and computerized system for detection and identification of microorganisms. Additionally, the system is designed to enumerate and provide antimicrobic susceptibility profiles for medically significant bacteria. The system is designed to accomplish these tasks in a time of 13 hours or less versus the traditional time of 24 hours for negatives and 72 hours or more for positives usually required for standard microbiological analysis. The MLM concept differs from other methods of microbial detection in that the system is designed to accept raw untreated clinical samples and to selectively identify each group or species that may be present in a polymicrobic sample.

  16. Plug Loads Conservation Measures

    SciTech Connect

    Ian Metzger, Jesse Dean

    2010-12-31

    This software requires inputs of simple plug loads inventory information and calculates the energy and cost benefits of various retrofit opportunities. This tool includes energy conservation measures for: Vending Machine Misers, Delamp Vending Machine, Desktop to Laptop retrofit, CRT to LCD monitors retrofit, Computer Power Management Settings, and Energy Star Refrigerator retrofit. This tool calculates energy savings, demand reduction, cost savings, building life cycle costs including: simple payback, discounted payback, net-present value, and savings to investment ratio. In addition this tool also displays the environmental benefits of a project.

  17. Nanoengineered Additives for Active Coatings

    DTIC Science & Technology

    2007-04-01

    commercial ad bial activ component from the coating, leading to eventual depletion of the film. Small TPU samples were evaluated using a Kirby - Bauer ...7 Table 5. Summary of 24-hr ASTM E 2180 tests with 1 weight-percent additive in PUr (solvent dispersible) based on 6-log loading of...Noveon X-1150). The ASTM E 2180 test is run in triplicate (Note that alternative ro 1° amines) was suspended in dry tetrahydrofuran (THF) (150 mL) in

  18. Brain oscillatory 4-30 Hz responses during a visual n-back memory task with varying memory load.

    PubMed

    Pesonen, Mirka; Hämäläinen, Heikki; Krause, Christina M

    2007-03-23

    Brain oscillatory responses of 4-30 Hz EEG frequencies elicited during the performance of a visual n-back task were examined in 36 adult volunteers. Event-related desynchronization (ERD) and event-related synchronization (ERS) responses were examined separately for targets and non-targets in four different memory load conditions (0-, 1-, 2- and 3-back). The presentation of all stimuli in all memory load conditions elicited long-lasting theta frequency (approximately 4-6 Hz) ERS responses which were of greater magnitude for the target stimuli as compared to the non-target stimuli. Alpha frequency range (approximately 8-12 Hz) ERD responses were observed in all memory load conditions for both targets and non-targets. The duration of these alpha ERD responses increased with increasing memory load and reaction time. In all memory load conditions, early appearing beta rhythm (approximately 14-30 Hz) ERD responses were elicited, and with increasing memory load, these beta ERD responses became longer in duration. Additionally, beta ERS responses were observed in the 0- and 1-back memory load conditions. The current results reveal a complex interplay between brain oscillations at different frequencies during a cognitive task performance.

  19. Factors affecting cognitive functioning in a sample of human immunodeficiency virus-positive injection drug users.

    PubMed

    Margolin, Arthur; Avants, S Kelly; Warburton, Lara A; Hawkins, Keith A

    2002-06-01

    Injection drug users represent a major vector of human immunodeficiency virus (HIV) infection in the nation's inner cities, and are an important population for harm reduction treatment interventions to target. However, there has been relatively little research examining the specific contribution of the multiple factors contributing to cognitive functioning among injection drug users that may affect engagement in, and response to, addiction and HIV-related interventions. The current study examined the independent contributions to neuropsychological (NP) test performance of premorbid educational attainment, medical and psychiatric history, long- and short-term drug use, assessed by laboratory, observation, and self-report measures, and HIV disease, assessed by plasma HIV-1 RNA viral load and CD4+ count, in a sample of 90 HIV-positive injection drug users dually addicted to heroin and cocaine. Fully 88% of the sample showed evidence of impairment (>1 standard deviation below the population mean) on an NP test battery selected to assess processes associated with successful engagement in the treatment of substance abuse and HIV, such as learning and memory of verbal information, capacity to solve new problems and deal with more than one stimulus at a time, visual-motor coordination, and visual tracking and cognitive flexibility. In addition to drug use, independent predictors of NP test performance were HIV viral load, educational attainment, and premorbid medical and psychiatric problems. Findings underscore the multiplicity of factors that contribute to cognitive impairment in HIV-positive drug-abusing individuals in addition to drug use. Clinical implications are discussed.

  20. Cognitive Enhancement and Education

    ERIC Educational Resources Information Center

    Buchanan, Allen

    2011-01-01

    Cognitive enhancement--augmenting normal cognitive capacities--is not new. Literacy, numeracy, computers, and the practices of science are all cognitive enhancements. Science is now making new cognitive enhancements possible. Biomedical cognitive enhancements (BCEs) include the administration of drugs, implants of genetically engineered or…

  1. White-matter vascular lesions correlate with alpha EEG sources in mild cognitive impairment.

    PubMed

    Babiloni, Claudio; Frisoni, Giovanni B; Pievani, Michela; Toscano, Leonia; Del Percio, Claudio; Geroldi, Cristina; Eusebi, Fabrizio; Miniussi, Carlo; Rossini, Paolo M

    2008-01-01

    It is an open issue if vascular and Alzheimer's disease (AD) lesions represent additive factors in the development of mild cognitive impairment (MCI), as a preclinical stage of Alzheimer's disease (AD) at group level. In the present study, we tested the hypothesis that electroencephalographic (EEG) alpha rhythms, which are affected (i.e. decreased in amplitude) by AD processes, are relatively preserved in MCI subjects in whom the cognitive decline is mainly explained by white-matter vascular load. Resting EEG was recorded in 40 healthy elderly (Nold), 80 MCI, and 40 AD subjects. In the MCI subjects, white-matter vascular load was quantified based on MRI (0-30 Wahlund visual rating scale). EEG rhythms of interest were delta (2-4Hz), theta (4-8Hz), alpha 1 (8-10.5Hz), alpha 2 (10.5-13Hz), beta 1 (13-20Hz), and beta 2 (20-30Hz). Low resolution electromagnetic source tomography (LORETA) was used for EEG source analysis. As expected, we observed that alpha 1 sources in parietal, occipital, and temporal areas were lower in amplitude in the AD and MCI subjects than in the Nold subjects, whereas the amplitude of wide delta sources was higher in the AD than in the Nold and MCI subjects. As novel results, the amplitude of parietal, occipital, and temporal alpha 1 sources was higher in the MCI V+ (high vascular load; N=42; MMSE=26) than MCI V- group (low vascular load; N=37; MMSE=26.7). Furthermore, a weak but significant (p<0.05) positive statistical correlation was found between the parietal alpha 1 sources and the score of Wahlund scale across all MCI subjects (i.e. the more severe white-matter lesions, the higher parietal alpha source power). The present results are in line with the additive model of cognitive impairment postulating that this arises as the sum of neurodegenerative and cerebrovascular lesions.

  2. Rational thinking and cognitive sophistication: development, cognitive abilities, and thinking dispositions.

    PubMed

    Toplak, Maggie E; West, Richard F; Stanovich, Keith E

    2014-04-01

    We studied developmental trends in 5 important reasoning tasks that are critical components of the operational definition of rational thinking. The tasks measured denominator neglect, belief bias, base rate sensitivity, resistance to framing, and the tendency toward otherside thinking. In addition to age, we examined 2 other individual difference domains that index cognitive sophistication: cognitive ability (intelligence and executive functioning) and thinking dispositions (actively open-minded thinking, superstitious thinking, and need for cognition). All 5 reasoning domains were consistently related to cognitive sophistication regardless of how it was indexed (age, cognitive ability, thinking dispositions). The implications of these findings for taxonomies of developmental trends in rational thinking tasks are discussed.

  3. Digital Game-Based Learning Supports Student Motivation, Cognitive Success, and Performance Outcomes

    ERIC Educational Resources Information Center

    Woo, Jeng-Chung

    2014-01-01

    Traditional multimedia learning is primarily based on the cognitive load concept of information processing theory. Recent digital game-based learning (DGBL) studies have focused on exploring content support for learning motivation and related game characteristics. Motivation, volition, and performance (MVP) theory indicates that cognitive load and…

  4. Complex motor-cognitive factors processed in the anterior nucleus of the thalamus: an intracerebral recording study.

    PubMed

    Bočková, Martina; Chládek, Jan; Jurák, Pavel; Halámek, Josef; Štillová, Klára; Baláž, Marek; Chrastina, Jan; Rektor, Ivan

    2015-03-01

    Cognitive adverse effects were reported after the deep brain stimulation (DBS) of the anterior nucleus of the thalamus (AN) in epilepsy. As the AN may have an influence on widespread neocortical networks, we hypothesized that the AN, in addition to its participation in memory processing, may also participate in cognitive activities linked with the frontal neocortical structures. The aim of this study was to investigate whether the AN might participate in complex motor-cognitive activities. Three pharmacoresistant epilepsy patients implanted with AN-DBS electrodes performed two tasks involving the writing of single letters: (1) copying letters from a monitor; and (2) writing of any letter other than that appearing on the monitor. The cognitive load of the second task was increased. The task-related oscillatory changes and evoked potentials were assessed. Local event-related alpha and beta desynchronization were more expressed during the second task while the lower gamma synchronization decreased. The local field event-related potentials were elicited by the two tasks without any specific differences. The AN participates in cognitive networks processing complex motor-cognitive tasks. Attention should be paid to executive functions in subjects undergoing AN-DBS.

  5. 1993 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1993-12-01

    The Loads and Resources Study is presented in three documents: (1) this summary of Federal system and Pacific Northwest region loads and resources; (2) a technical appendix detailing forecasted Pacific Northwest economic trends and loads, and (3) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. In this loads and resources study, resource availability is compared with a range of forecasted electricity consumption. The forecasted future electricity demands -- firm loads -- are subtracted from the projected capability of existing and {open_quotes}contracted for{close_quotes} resources to determine whether Bonneville Power Administration (BPA) and the region will be surplus or deficit. If resources are greater than loads in any particular year or month, there is a surplus of energy and/or capacity, which BPA can sell to increase revenues. Conversely, if firm loads exceed available resources, there is a deficit of energy and/or capacity, and additional conservation, contract purchases, or generating resources will be needed to meet load growth. The Pacific Northwest Loads and Resources Study analyzes the Pacific Northwest`s projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional power system, which includes loads and resource in addition to the Federal system. The loads and resources analysis in this study simulates the operation of the power system under the Pacific Northwest Coordination Agreement (PNCA) produced by the Pacific Northwest Coordinating Group. This study presents the Federal system and regional analyses for five load forecasts: high, medium-high, medium, medium-low, and low. This analysis projects the yearly average energy consumption and resource availability for Operating Years (OY) 1994--95 through 2003--04.

  6. Additive-driven assembly of block copolymers

    NASA Astrophysics Data System (ADS)

    Lin, Ying; Daga, Vikram; Anderson, Eric; Watkins, James

    2011-03-01

    One challenge to the formation of well ordered hybrid materials is the incorporation of nanoscale additives including metal, semiconductor and dielectric nanoparticles at high loadings while maintaining strong segregation. Here we describe the molecular and functional design of small molecule and nanoparticle additives that enhance phase segregation in their block copolymer host and enable high additive loadings. Our approach includes the use of hydrogen bond interactions between the functional groups on the additive or particle that serve as hydrogen bond donors and one segment of the block copolymer containing hydrogen bond acceptors. Further, the additives show strong selectively towards the targeted domains, leading to enhancements in contrast between properties of the phases. In addition to structural changes, we explore how large changes in the thermal and mechanical properties occur upon incorporation of the additives. Generalization of this additive-induced ordering strategy to various block copolymers will be discussed.

  7. Cognitive Fatigue Facilitates Procedural Sequence Learning

    PubMed Central

    Borragán, Guillermo; Slama, Hichem; Destrebecqz, Arnaud; Peigneux, Philippe

    2016-01-01

    Enhanced procedural learning has been evidenced in conditions where cognitive control is diminished, including hypnosis, disruption of prefrontal activity and non-optimal time of the day. Another condition depleting the availability of controlled resources is cognitive fatigue (CF). We tested the hypothesis that CF, eventually leading to diminished cognitive control, facilitates procedural sequence learning. In a two-day experiment, 23 young healthy adults were administered a serial reaction time task (SRTT) following the induction of high or low levels of CF, in a counterbalanced order. CF was induced using the Time load Dual-back (TloadDback) paradigm, a dual working memory task that allows tailoring cognitive load levels to the individual’s optimal performance capacity. In line with our hypothesis, reaction times (RT) in the SRTT were faster in the high- than in the low-level fatigue condition, and performance improvement was higher for the sequential than the motor components. Altogether, our results suggest a paradoxical, facilitating impact of CF on procedural motor sequence learning. We propose that facilitated learning in the high-level fatigue condition stems from a reduction in the cognitive resources devoted to cognitive control processes that normally oppose automatic procedural acquisition mechanisms. PMID:26973501

  8. Psychosocial factors and mental work load: a reality perceived by nurses in intensive care units1

    PubMed Central

    Ceballos-Vásquez, Paula; Rolo-González, Gladys; Hérnandez-Fernaud, Estefanía; Díaz-Cabrera, Dolores; Paravic-Klijn, Tatiana; Burgos-Moreno, Mónica

    2015-01-01

    OBJECTIVE: To analyse the perception of psychosocial factors and mental workload of nurses who work in intensive care units. It is hypothesised that nurses in these units could perceive psychosocial risks, manifesting in a high mental work load. The psychosocial dimension related to the position's cognitive demands is hypothesised to mostly explain mental work load. METHOD: Quantitative study, with a descriptive, cross-sectional, and comparative design. A total of 91% of the intensive care unit populations of three Chilean hospitals was surveyed, corresponding to 111 nurses. The instruments utilised included (A) a biosociodemographic history questionnaire; (b) the SUSESO-ISTAS 21 questionnaire; and (c) the Mental Work Load Subjective Scale (ESCAM, in Spanish). RESULTS: In total, 64% and 57% of participants perceived high levels of exposure to the psychosocial risks Psychosocial demands and Double shift, respectively. In addition, a medium-high level of overall mental load was observed. Positive and significant correlations between some of the SUSESO-ISTAS 21 and ESCAM dimensions were obtained. Using a regression analysis, it was determined that three dimensions of the psychosocial risk questionnaire helped to explain 38% of the overall mental load. CONCLUSION: Intensive care unit nurses felt that inadequate psychosocial factors and mental work overload existed in several of the tested dimensions. PMID:26039303

  9. White matter vascular lesions are related to parietal-to-frontal coupling of EEG rhythms in mild cognitive impairment.

    PubMed

    Babiloni, Claudio; Frisoni, Giovanni B; Pievani, Michela; Vecchio, Fabrizio; Infarinato, Francesco; Geroldi, Cristina; Salinari, Serenella; Ferri, Raffaele; Fracassi, Claudia; Eusebi, Fabrizio; Rossini, Paolo M

    2008-12-01

    Do cerebrovascular and Alzheimer's disease (AD) lesions represent additive factors in the development of mild cognitive impairment (MCI) as a putative preclinical stage of AD? Here we tested the hypothesis that directionality of fronto-parietal functional coupling of electroencephalographic (EEG) rhythms is relatively preserved in amnesic MCI subjects in whom the cognitive decline is mainly explained by white-matter vascular load. Resting EEG was recorded in 40 healthy elderly (Nold) and 78 amnesic MCI. In the MCI subjects, white-matter vascular load was quantified based on magnetic resonance images (0-30 visual rating scale). EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha1 (8-10.5 Hz), alpha2 (10.5-13 Hz), beta1 (13-20 Hz), and beta2 (20-30 Hz). Directionality of fronto-parietal functional coupling of EEG rhythms was estimated by directed transfer function software. As main results, (i) fronto-parietal functional coupling of EEG rhythms was higher in magnitude in the Nold than in the MCI subjects; (ii) more interestingly, that coupling was higher at theta, alpha1, alpha2, and beta1 in MCI V+ (high vascular load; N = 42; MMSE = 26) than in MCI V- group (low vascular load; N = 36; MMSE= 26.7). These results are interpreted as supporting the additive model according to which MCI state would result from the combination of cerebrovascular and neurodegenerative lesions.

  10. Impact of age and cognitive demand on lane choice and changing under actual highway conditions.

    PubMed

    Reimer, Bryan; Donmez, Birsen; Lavallière, Martin; Mehler, Bruce; Coughlin, Joseph F; Teasdale, Normand

    2013-03-01

    Previous research suggests that drivers change lanes less frequently during periods of heightened cognitive load. However, lane changing behavior of different age groups under varying levels of cognitive demand is not well understood. The majority of studies which have evaluated lane changing behavior under cognitive workload have been conducted in driving simulators. Consequently, it is unclear if the patterns observed in these simulation studies carry over to actual driving. This paper evaluates data from an on-road study to determine the effects of age and cognitive demand on lane choice and lane changing behavior. Three age groups (20-29, 40-49, and 60-69) were monitored in an instrumented vehicle. The 40's age group had 147% higher odds of exhibiting a lane change than the 60's group. In addition, drivers in their 60's were less likely to drive on the leftmost lane compared to drivers in their 20's and 40's. These results could be interpreted as evidence that older adults adopt a more conservative driving style as reflected in being less likely to choose the leftmost lane than the younger groups and less likely to change lanes than drivers in their 40's. Regardless of demand level, cognitive workload reduced the frequency of lane changes for all age groups. This suggests that in general drivers of all ages attempt to regulate their behavior in a risk reducing direction when under added cognitive demand. The extent to which such self-regulation fully compensates for the impact of added cognitive demand remains an open question.

  11. Cognitive Remediation Strategies

    PubMed Central

    WEINSTEIN, CHERYL S.

    1994-01-01

    Evidence continues to emerge that childhood symptoms of attention-deficit hyperactivity disorder (ADHD) persist into adulthood. These symptoms include motoric hyperactivity, restlessness, attention deficits, poor organizational skills, impulsivity, and memory impairment. Poor academic and work performance, frustration, humiliation, and shame are also components of adult ADHD. Psychotherapists are challenged to understand the meaning of the disorder and its ramifications in all aspects of life. An active multimodal approach, including somatic treatment and psychotherapy, is needed. In addition, cognitive remediation strategies to enhance attention, organization, memory, and problem-solving skills are an important adjunct to treatment. These strategies serve as psychological tools to circumvent deficits. PMID:22700173

  12. Information processing, computation, and cognition.

    PubMed

    Piccinini, Gualtiero; Scarantino, Andrea

    2011-01-01

    Computation and information processing are among the most fundamental notions in cognitive science. They are also among the most imprecisely discussed. Many cognitive scientists take it for granted that cognition involves computation, information processing, or both - although others disagree vehemently. Yet different cognitive scientists use 'computation' and 'information processing' to mean different things, sometimes without realizing that they do. In addition, computation and information processing are surrounded by several myths; first and foremost, that they are the same thing. In this paper, we address this unsatisfactory state of affairs by presenting a general and theory-neutral account of computation and information processing. We also apply our framework by analyzing the relations between computation and information processing on one hand and classicism, connectionism, and computational neuroscience on the other. We defend the relevance to cognitive science of both computation, at least in a generic sense, and information processing, in three important senses of the term. Our account advances several foundational debates in cognitive science by untangling some of their conceptual knots in a theory-neutral way. By leveling the playing field, we pave the way for the future resolution of the debates' empirical aspects.

  13. Can exercise prevent cognitive decline?

    PubMed

    Behrman, Sophie; Ebmeier, Klaus P

    2014-01-01

    As the tolerability of pharmacological agents decreases with age, exercise may be particularly helpful as a possible treatment or stabiliser of mood and cognitive function in older age. Exercise has been most commonly evaluated for the treatment of depression. Exercise interventions designed primarily for treatment of physical conditions in the elderly do appear to confer psychological benefits as well, with reduction in depressive symptoms over the course of treatment. The effects of exercise on reducing depressive symptoms are not dissimilar to the effects of antidepressant drugs and cognitive behaviour therapy. Exercise may be a useful low-tech intervention for people with mild to moderate depression. In particular, exercise may be helpful in the elderly and in patients who have had insufficient response to, or are intolerant of, pharmacotherapy. Mastery of a new skill and positive feedback from others may increase feelings of self-esteem and improve mood. Exercise may distract participants from persistent negative thoughts. Exercise has been shown to improve executive function acutely in adults of all ages. It is possible that dance routines or other exercise regimens requiring some cognitive input may confer additional benefit to cognitive function. Exercise has a moderate effect on the ability of people with dementia to perform activities of daily living and may improve cognitive function. Midlife exercise may also have an impact on later cognitive function.

  14. Attitudes and cognitive distances: On the non-unitary and flexible nature of cognitive maps

    PubMed Central

    Carbon, Claus-Christian; Hesslinger, Vera M.

    2013-01-01

    Spatial relations of our environment are represented in cognitive maps. These cognitive maps are prone to various distortions (e.g., alignment and hierarchical effects) caused by basic cognitive factors (such as perceptual and conceptual reorganization) but also by affectively loaded and attitudinal influences. Here we show that even differences in attitude towards a single person representing a foreign country (here Barack Obama and the USA) can be related to drastic differences in the cognitive representation of distances concerning that country. Europeans who had a positive attitude towards Obama’s first presidential program estimated distances between US and European cities as being much smaller than did people who were skeptical or negative towards Obama’s ideas. On the basis of this result and existing literature, arguments on the non-unitary and flexible nature of cognitive maps are discussed. PMID:24155860

  15. Attitudes and cognitive distances: On the non-unitary and flexible nature of cognitive maps.

    PubMed

    Carbon, Claus-Christian; Hesslinger, Vera M

    2013-01-01

    Spatial relations of our environment are represented in cognitive maps. These cognitive maps are prone to various distortions (e.g., alignment and hierarchical effects) caused by basic cognitive factors (such as perceptual and conceptual reorganization) but also by affectively loaded and attitudinal influences. Here we show that even differences in attitude towards a single person representing a foreign country (here Barack Obama and the USA) can be related to drastic differences in the cognitive representation of distances concerning that country. Europeans who had a positive attitude towards Obama's first presidential program estimated distances between US and European cities as being much smaller than did people who were skeptical or negative towards Obama's ideas. On the basis of this result and existing literature, arguments on the non-unitary and flexible nature of cognitive maps are discussed.

  16. Beyond single-level accounts: the role of cognitive architectures in cognitive scientific explanation.

    PubMed

    Cooper, Richard P; Peebles, David

    2015-04-01

    We consider approaches to explanation within the cognitive sciences that begin with Marr's computational level (e.g., purely Bayesian accounts of cognitive phenomena) or Marr's implementational level (e.g., reductionist accounts of cognitive phenomena based only on neural-level evidence) and argue that each is subject to fundamental limitations which impair their ability to provide adequate explanations of cognitive phenomena. For this reason, it is argued, explanation cannot proceed at either level without tight coupling to the algorithmic and representation level. Even at this level, however, we argue that additional constraints relating to the decomposition of the cognitive system into a set of interacting subfunctions (i.e., a cognitive architecture) are required. Integrated cognitive architectures that permit abstract specification of the functions of components and that make contact with the neural level provide a powerful bridge for linking the algorithmic and representational level to both the computational level and the implementational level.

  17. Effects of First Occasion Test Experience on Longitudinal Cognitive Change

    ERIC Educational Resources Information Center

    Salthouse, Timothy A.

    2013-01-01

    Effects of additional test experience on longitudinal change in 5 cognitive abilities was examined in a sample of healthy adults ranging from 18 to 80 years of age. Participants receiving experience with parallel versions of the cognitive tests on the first occasion had more positive cognitive change an average of 2.5 years later than participants…

  18. Challenges in the use of treatment to investigate cognition.

    PubMed

    Nickels, Lyndsey; Rapp, Brenda; Kohnen, Saskia

    2015-01-01

    The use of data from people with cognitive impairments to inform theories of cognition is an established methodology, particularly in the field of cognitive neuropsychology. However, it is less well known that studies that aim to improve cognitive functioning using treatment can also inform our understanding of cognition. This paper discusses a range of challenges that researchers face when testing theories of cognition and particularly when using treatment as a tool for doing so. It highlights the strengths of treatment methodology for testing causal relations and additionally discusses how generalization of treatment effects can shed light on the nature of cognitive representations and processes. These points are illustrated using examples from the Special Issue of Cognitive Neuropsychology entitled Treatment as a tool for investigating cognition.

  19. Challenges in the use of treatment to investigate cognition

    PubMed Central

    Nickels, Lyndsey; Rapp, Brenda; Kohnen, Saskia

    2016-01-01

    The use of data from people with cognitive impairments to inform theories of cognition is an established methodology, particularly in the field of cognitive neuropsychology. However, it is less well-known that studies that aim to improve cognitive functioning using treatment can also inform our understanding of cognition. This paper discusses a range of challenges researchers face when testing theories of cognition and particularly when using treatment as a tool for doing so. It highlights the strengths of treatment methodology for testing causal relations and additionally discusses how generalisation of treatment effects can shed light on the nature of cognitive representations and processes. These points are illustrated using examples from the Special Issue of Cognitive Neuropsychology entitled Treatment as a tool for investigating cognition. PMID:26377505

  20. Load Control System Reliability

    SciTech Connect

    Trudnowski, Daniel

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  1. 14 CFR 23.509 - Towing loads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... In addition: (1) A vertical load factor equal to 1.0 must be considered acting at the center of... main gear must be reacted as follows: (i) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of the wheel to which the load is applied. Enough airplane inertia...

  2. 14 CFR 23.509 - Towing loads.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... In addition: (1) A vertical load factor equal to 1.0 must be considered acting at the center of... main gear must be reacted as follows: (i) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of the wheel to which the load is applied. Enough airplane inertia...

  3. 14 CFR 23.509 - Towing loads.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... In addition: (1) A vertical load factor equal to 1.0 must be considered acting at the center of... main gear must be reacted as follows: (i) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of the wheel to which the load is applied. Enough airplane inertia...

  4. 14 CFR 23.509 - Towing loads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .... In addition: (1) A vertical load factor equal to 1.0 must be considered acting at the center of... main gear must be reacted as follows: (i) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of the wheel to which the load is applied. Enough airplane inertia...

  5. 14 CFR 23.509 - Towing loads.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... In addition: (1) A vertical load factor equal to 1.0 must be considered acting at the center of... main gear must be reacted as follows: (i) A reaction with a maximum value equal to the vertical reaction must be applied at the axle of the wheel to which the load is applied. Enough airplane inertia...

  6. Loads Combination Research at Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Ferebee, R.

    2000-01-01

    This is the result of a study conducted by the Structural Dynamics Division of the Marshall Space Flight Center concerning the combination of low- and high-frequency dynamic loads for spacecraft design. Low-frequency transient loads are combined with high frequency acoustically induced loads to arrive at a limit load, for design purposes. Different methods are used for combining the loads which can lead to considerable variation in limit loads, depending on which NASA Center did the calculation. This study investigates several different combination methods and compares the combination methods with Spacelab 1 flight data. In addition, the relative timing of low- and high-frequency loads is examined.

  7. Automated load management for spacecraft power systems

    NASA Technical Reports Server (NTRS)

    Lollar, Louis F.

    1987-01-01

    An account is given of the results of a study undertaken by NASA's Marshall Space Flight Center to design and implement the load management techniques for autonomous spacecraft power systems, such as the Autonomously Managed Power System Test Facility. Attention is given to four load-management criteria, which encompass power bus balancing on multichannel power systems, energy balancing in such systems, power quality matching of loads to buses, and contingency load shedding/adding. Full implementation of these criteria calls for the addition of a second power channel.

  8. An exploratory study of the effects of spatial working-memory load on prefrontal activation in low- and high-performing elderly

    PubMed Central

    Vermeij, Anouk; van Beek, Arenda H. E. A.; Reijs, Babette L. R.; Claassen, Jurgen A. H. R.; Kessels, Roy P. C.

    2014-01-01

    Older adults show more bilateral prefrontal activation during cognitive performance than younger adults, who typically show unilateral activation. This over-recruitment has been interpreted as compensation for declining structure and function of the brain. Here we examined how the relationship between behavioral performance and prefrontal activation is modulated by different levels of working-memory load. Eighteen healthy older adults (70.8 ± 5.0 years; MMSE 29.3 ± 0.9) performed a spatial working-memory task (n-back). Oxygenated ([O2Hb]) and deoxygenated ([HHb]) hemoglobin concentration changes were registered by two functional Near-Infrared Spectroscopy (fNIRS) channels located over the left and right prefrontal cortex. Increased working-memory load resulted in worse performance compared to the control condition. [O2Hb] increased with rising working-memory load in both fNIRS channels. Based on the performance in the high working-memory load condition, the group was divided into low and high performers. A significant interaction effect of performance level and hemisphere on [O2Hb] increase was found, indicating that high performers were better able to keep the right prefrontal cortex engaged under high cognitive demand. Furthermore, in the low performers group, individuals with a larger decline in task performance from the control to the high working-memory load condition had a larger bilateral increase of [O2Hb]. The high performers did not show a correlation between performance decline and working-memory load related prefrontal activation changes. Thus, additional bilateral prefrontal activation in low performers did not necessarily result in better cognitive performance. Our study showed that bilateral prefrontal activation may not always be successfully compensatory. Individual behavioral performance should be taken into account to be able to distinguish successful and unsuccessful compensation or declined neural efficiency. PMID:25414665

  9. An exploratory study of the effects of spatial working-memory load on prefrontal activation in low- and high-performing elderly.

    PubMed

    Vermeij, Anouk; van Beek, Arenda H E A; Reijs, Babette L R; Claassen, Jurgen A H R; Kessels, Roy P C

    2014-01-01

    Older adults show more bilateral prefrontal activation during cognitive performance than younger adults, who typically show unilateral activation. This over-recruitment has been interpreted as compensation for declining structure and function of the brain. Here we examined how the relationship between behavioral performance and prefrontal activation is modulated by different levels of working-memory load. Eighteen healthy older adults (70.8 ± 5.0 years; MMSE 29.3 ± 0.9) performed a spatial working-memory task (n-back). Oxygenated ([O2Hb]) and deoxygenated ([HHb]) hemoglobin concentration changes were registered by two functional Near-Infrared Spectroscopy (fNIRS) channels located over the left and right prefrontal cortex. Increased working-memory load resulted in worse performance compared to the control condition. [O2Hb] increased with rising working-memory load in both fNIRS channels. Based on the performance in the high working-memory load condition, the group was divided into low and high performers. A significant interaction effect of performance level and hemisphere on [O2Hb] increase was found, indicating that high performers were better able to keep the right prefrontal cortex engaged under high cognitive demand. Furthermore, in the low performers group, individuals with a larger decline in task performance from the control to the high working-memory load condition had a larger bilateral increase of [O2Hb]. The high performers did not show a correlation between performance decline and working-memory load related prefrontal activation changes. Thus, additional bilateral prefrontal activation in low performers did not necessarily result in better cognitive performance. Our study showed that bilateral prefrontal activation may not always be successfully compensatory. Individual behavioral performance should be taken into account to be able to distinguish successful and unsuccessful compensation or declined neural efficiency.

  10. Diet, gut microbiota and cognition.

    PubMed

    Proctor, Cicely; Thiennimitr, Parameth; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2017-02-01

    The consumption of a diet high in fat and sugar can lead to the development of obesity, type 2 diabetes mellitus (T2DM), cardiovascular disease and cognitive decline. In the human gut, the trillions of harmless microorganisms harboured in the host's gastrointestinal tract are called the 'gut microbiota'. Consumption of a diet high in fat and sugar changes the healthy microbiota composition which leads to an imbalanced microbial population in the gut, a phenomenon known as "gut dysbiosis". It has been shown that certain types of gut microbiota are linked to the pathogenesis of obesity. In addition, long-term consumption of a high fat diet is associated with cognitive decline. It has recently been proposed that the gut microbiota is part of a mechanistic link between the consumption of a high fat diet and the impaired cognition of an individual, termed "microbiota-gut-brain axis". In this complex relationship between the gut, the brain and the gut microbiota, there are several types of gut microbiota and host mechanisms involved. Most of these mechanisms are still poorly understood. Therefore, this review comprehensively summarizes the current evidence from mainly in vivo (rodent and human) studies of the relationship between diet, gut microbiota and cognition. The possible mechanisms that the diet and the gut microbiota have on cognition are also presented and discussed.

  11. Music cognition and the cognitive sciences.

    PubMed

    Pearce, Marcus; Rohrmeier, Martin

    2012-10-01

    Why should music be of interest to cognitive scientists, and what role does it play in human cognition? We review three factors that make music an important topic for cognitive scientific research. First, music is a universal human trait fulfilling crucial roles in everyday life. Second, music has an important part to play in ontogenetic development and human evolution. Third, appreciating and producing music simultaneously engage many complex perceptual, cognitive, and emotional processes, rendering music an ideal object for studying the mind. We propose an integrated status for music cognition in the Cognitive Sciences and conclude by reviewing challenges and big questions in the field and the way in which these reflect recent developments.

  12. Screening for Cognitive Impairments in Primary Blepharospasm

    PubMed Central

    Yang, Jing; Song, Wei; Wei, Qianqian; Ou, Ruwei; Cao, Bei; Liu, Wanglin; Shao, Na; Shang, Hui-Fang

    2016-01-01

    Backgrounds Studies have reported that non-motor symptoms are an important component of primary dystonia. However, evidence supporting cognitive impairment in primary dystonia is limited and contradictory. Methods We applied the Chinese version of the Addenbrooke’s Cognitive Examination-Revised and the Mini-Mental State Examination (MMSE) to screen for cognitive impairment in patients with primary blepharospasm. In addition, we investigated the relationship between performance on the Addenbrooke’s Cognitive Examination-Revised and quality of life as measured by the Medical Outcomes Study 36-item Short-Form (SF36). Results The study included 68 primary blepharospasm patients and 68 controls matched by age, sex and education. The prevalence of cognitive deficits was 22.0% and 32.3% in primary blepharospasm patients group, as measured by the MMSE and the Addenbrooke’s Cognitive Examination-Revised, respectively. Primary blepharospasm patents had a broad range of cognitive deficits, with the most frequently affected domains being visuospatial function (30.9%) and language (30.9%), followed by memory (27.9%), orientation/attention (26.4%) and verbal fluency (22.0%). Patients with cognitive deficits had lower total SF36 scores, especially in the subdomains of physical functioning, role-physical and social functioning, compared to those without cognitive deficits. Scores on the Addenbrooke’s Cognitive Examination-Revised were significantly correlated with both the SF36 scores and the scores on the subdomains of physical functioning and social functioning. Conclusions Some patients with primary blepharospasm have cognitive deficits. Poor performance on the Addenbrooke’s Cognitive Examination-Revised is related to poorer quality of life. PMID:27526026

  13. Load sensing system

    DOEpatents

    Sohns, Carl W.; Nodine, Robert N.; Wallace, Steven Allen

    1999-01-01

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast

  14. Exploring Cognitive Diversity: Anthropological Perspectives on Cognition.

    PubMed

    Beller, Sieghard; Bender, Andrea

    2015-10-01

    Anthropology and the other cognitive sciences currently maintain a troubled relationship (Beller, Bender, & Medin, ). What could rapprochement look like, and how could it be achieved? The seven main articles of this topic present anthropological or anthropologically inspired cross-cultural research on a diverse set of cognitive domains. They serve as an existence proof that not only do synergies abound across anthropology and the other cognitive sciences, but that they are worth achieving.

  15. Ecophysiology of cognition: How do environmentally induced changes in physiology affect cognitive performance?

    PubMed

    Maille, Audrey; Schradin, Carsten

    2017-05-01

    Cognitive performance is based on brain functions, which have energetic demands and are modulated by physiological parameters such as metabolic hormones. As both environmental demands and environmental energy availability change seasonally, we propose that cognitive performance in free-living animals might also change seasonally due to phenotypic plasticity. This is part of an emerging research field, the 'ecophysiology of cognition': environmentally induced changes in physiological traits, such as blood glucose and hormone levels, are predicted to influence cognitive performance in free-living animals. Energy availability for the brain might change, and as such cognition, with changing energetic demands (e.g. reproduction) and changes of energy availability in the environment (e.g. winter, drought). Individuals spending more energy than they can currently obtain from their environment (allostatic overload type I) are expected to trade off energy investment between cognition and other life-sustaining processes or even reproduction. Environmental changes reducing energy availability might thus impair cognition. However, selection pressures such as predation risk, mate choice or social demands may act on the trade-off between energy saving and cognition. We assume that different environmental conditions can lead to three different trade-off outcomes: cognitive impairment, resilience or enhancement. Currently we cannot understand these trade-offs, because we lack information about changes in cognitive performance due to seasonal changes in energy availability and both the resulting changes in homeostasis (for example, blood glucose levels) and the associated changes in the mechanisms of allostasis (for example, hormone levels). Additionally, so far we know little about the fitness consequences of individual variation in cognitive performance. General cognitive abilities, such as attention and associative learning, might be more important in determining fitness than

  16. The cognitive mechanisms underlying deception: an event-related potential study.

    PubMed

    Suchotzki, Kristina; Crombez, Geert; Smulders, Fren T Y; Meijer, Ewout; Verschuere, Bruno

    2015-03-01

    The cognitive view on deception proposes that lying comes with a cognitive cost. This view is supported by the finding that lying typically takes longer than truth telling. Event-related potentials (ERPs) provide a means to unravel the cognitive processes underlying this cost. Using a mock-crime design, the current study (n=20) investigated the effects of deception on the Contingent Negative Variation (CNV), the Lateralized Readiness Potential (LRP), the Correct Response Negativity (CRN), and the stimulus-locked N200 and P300 components. In line with previous research, lying resulted in more errors, longer reaction times (RTs) and longer RT standard deviations compared to truthful responses. A marginally significant effect suggested a stronger CNV for the anticipation of lying compared to the anticipation of truth telling. There were no significant deception effects on the stimulus- and the response-locked LRPs. Unexpectedly, we found a significantly larger CRN for truth telling compared to lying. Additional analyses revealed an enhanced N200 and a decreased P300 for lying compared to truth telling. Our results support the cognitive load hypothesis for lying, yet are mixed regarding the response conflict hypothesis. Results are discussed with regard to the specific characteristics of our design and their theoretical and applied implications.

  17. The Complexity of Jokes Is Limited by Cognitive Constraints on Mentalizing

    PubMed Central

    Launay, Jacques; Curry, Oliver

    2016-01-01

    Although laughter is probably of deep evolutionary origin, the telling of jokes, being language-based, is likely to be of more recent origin within the human lineage. In language-based communication, speaker and listener are engaged in a process of mutually understanding each other’s intentions (mindstates), with a conversation minimally requiring three orders of intentionality. Mentalizing is cognitively more demanding than non-mentalizing cognition, and there is a well-attested limit at five orders in the levels of intentionality at which normal adult humans can work. Verbal jokes commonly involve commentary on the mindstates of third parties, and each such mindstate adds an additional level of intentionality and its corresponding cognitive load. We determined the number of mentalizing levels in a sample of jokes told by well-known professional comedians and show that most jokes involve either three or five orders of intentionality on the part of the comedian, depending on whether or not the joke involves other individuals’ mindstates. Within this limit there is a positive correlation between increasing levels of intentionality and subjective ratings of how funny the jokes are. The quality of jokes appears to peak when they include five to six levels of intentionality, which suggest that audiences appreciate higher mentalizing complexity whilst working within their natural cognitive constraints. PMID:26597196

  18. Distributed cognition artifacts on clinical research data collection forms.

    PubMed

    Nahm, Meredith; Nguyen, Vickie D; Razzouk, Elie; Zhu, Min; Zhang, Jiajie

    2010-03-01

    Medical record abstraction, a primary mode of data collection in secondary data use, is associated with high error rates. Cognitive factors have not been studied as a possible explanation for medical record abstraction errors. We employed the theory of distributed representation and representational analysis to systematically evaluate cognitive demands in medical record abstraction and the extent of external cognitive support employed in a sample of clinical research data collection forms.We show that the cognitive load required for abstraction in 61% of the sampled data elements was high, exceedingly so in 9%. Further, the data collection forms did not support external cognition for the most complex data elements. High working memory demands are a possible explanation for the association of data errors with data elements requiring abstractor interpretation, comparison, mapping or calculation. The representational analysis used here can be used to identify data elements with high cognitive demands.

  19. Cognitive behavioral therapy for back pain

    MedlinePlus

    ... back pain - cognitive behavioral; Backache - chronic - cognitive behavioral; Lumbar pain - chronic - cognitive behavioral; Pain - back - chronic - cognitive behavioral; Chronic back pain - low - cognitive behavioral

  20. Δ9-Tetrahydrocannabinol decreases willingness to exert cognitive effort in male rats

    PubMed Central

    Silveira, Mason M.; Adams, Wendy K.; Morena, Maria; Hill, Matthew N.; Winstanley, Catharine A.

    2017-01-01

    Background Acceptance of cannabis use is growing. However, prolonged use is associated with diminished psychosocial outcomes, potentially mediated by drug-induced cognitive impairments. Δ9-Tetrahydrocannabinol (THC) is the main psychoactive ingredient in cannabis, yet other phytocannabinoids in the plant, such as cannabidiol (CBD), have unique properties. Given that CBD can modulate the undesirable effects of THC, therapeutic agents, such as nabiximols, contain higher CBD:THC ratios than illicit marijuana. We tested the hypothesis that THC impairs a relevant cognitive function for long-term success, namely willingness to exert cognitive effort for greater rewards, and that CBD could attenuate such decision-making impairments. Methods Male Long–Evans rats (n = 29) performing the rat cognitive effort task (rCET) received acute THC and CBD, independently and concurrently, in addition to other cannabinoids. Rats chose between 2 options differing in reward magnitude, but also in the cognitive effort (attentional load) required to obtain them. Results We found that THC decreased choice of hard trials without impairing the animals’ ability to accurately complete them. Strikingly, this impairment was correlated with CB1 receptor density in the medial prefrontal cortex — an area previously implicated in effortful decision-making. In contrast, CBD did not affect choice. Coadministration of 1:1 CBD:THC matching that in nabiximols modestly attenuated the deleterious effects of THC in “slacker” rats. Limitations Only male rats were investigated, and the THC/CBD coadministration experiment was carried out in a subset of individuals. Conclusion These findings confirm that THC, but not CBD, selectively impairs decision-making involving cognitive effort costs. However, coadministration of CBD only partially ameliorates such THC-induced dysfunction. PMID:28245177