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.

Instructional Efficiency of Tutoring in an Outreach Gene Technology Laboratory

ERIC Educational Resources Information Center

Scharfenberg, Franz-Josef; Bogner, Franz X.

2013-01-01

Our research objective focused on examining the instructional efficiency of tutoring as a form of instructional change as opposed to a non-tutoring approach in an outreach laboratory. We designed our laboratory based on cognitive load (CL) theory. Altogether, 269 twelfth-graders participated in our day-long module "Genetic Fingerprinting." In a…

Cognitive Linguistics and the Second Language Classroom

ERIC Educational Resources Information Center

Holme, Randal

2012-01-01

Cognitive Linguistics (CL) makes the functional assumption that form is motivated by meaning. CL also analyses form-meaning pairings as products of how cognition structures perception. CL thus helps teachers to fit language to the nature of the cognition that learns whilst devising modes of instruction that are better attuned to the nature of the…

Chloride retention and release in a boreal forest soil: effects of soil water residence time and nitrogen and chloride loads.

PubMed

Bastviken, David; Sandén, Per; Svensson, Teresia; Ståhlberg, A Carina; Magounakis, Malin; Oberg, Gunilla

2006-05-01

The common assumption that chloride (Cl-) is conservative in soils and can be used as a groundwater tracer is currently being questioned, and an increasing number of studies indicate that Cl- can be retained in soils. We performed lysimeter experiments with soil from a coniferous forest in southeast Sweden to determine whether pore water residence time and nitrogen and Cl- loads affected Cl- retention. Over the first 42 days there was a net retention of Cl- with retention rates averaging 3.1 mg CI- m(-2) d(-1) (68% of the added Cl- retained over 42 days). Thereafter, a net release of Cl- at similar rates was observed for the remaining experimental period (85 d). Longer soil water residence time and higher Cl- load gave higher initial retention and subsequent release rates than shorter residence time and lower Cl- load did. Nitrogen load did not affect Cl transformation rates. This study indicates that simultaneous retention and release of Cl- can occur in soils, and that rates may be considerable relative to the load. The retention of Cl- observed was probably due to chlorination of soil organic matter or ion exchange. The cause of the shift between net retention and net release is unclear, but we hypothesize that the presence of O2 or the presence of microbially available organic matter regulates Cl- retention and release rates.

Teacher Language Awareness and Cognitive Linguistics (CL): Building a CL-Inspired Perspective on Teaching Lexis in EFL Student Teachers

ERIC Educational Resources Information Center

Giebler, Ralf

2012-01-01

It has been suggested recently that it may be useful for language teaching practitioners to have some knowledge of cognitive linguistics. Cognitive linguistics (CL) provides tools that may help the language-teaching practitioner to gain insight into the semantic potential of words and communicate the meaning of lexical chunks in greater detail…

The Influences of Cognitive Styles on Individual Learning and Collaborative Learning

ERIC Educational Resources Information Center

Chen, Sherry Y.; Chang, Li-Ping

2016-01-01

Both individual learning (IL) and collaborative learning (CL) provide students with different benefits. However, previous research indicates that cognitive styles affect students' learning preferences. Thus, it is necessary to examine how cognitive styles influence students' reactions to IL and CL. Among various cognitive styles, Pask's…

Effects of Highway Road Salting on the Water Quality of Selected Streams in Chittenden County, Vermont, November 2005-2007

USGS Publications Warehouse

Denner, Jon C.; Clark, Stewart F.; Smith, Thor E.; Medalie, Laura

2010-01-01

A study of road-deicing chloride (Cl) concentrations and loads was conducted at three streams in Chittenden County, VT, from November 2005 to 2007. This study was done by the U.S. Geological Survey, in cooperation with the Vermont Agency of Transportation. The streams, Alder Brook, Allen Brook, and Mill Brook, were selected to represent different land uses in the upstream watershed, different road types and densities, and different geometric patterns of the roadway draining to the receiving stream to assess the relative contribution of and differences in state road-salt applications to stream Cl concentrations and loads. Water-quality samples were collected and specific conductance was measured continuously at paired stations upstream and downstream from State highways and related to Cl concentrations to assist in determining the effects of road-salting operations during winter maintenance on the levels of Cl in the streams. Mean concentrations of Cl ranged from 8.2 to 72 mg/L (milligrams per liter) in the water-quality samples collected at sampling stations upstream from State highway bridges and from 7.9 to 80 mg/L in those collected at sampling stations downstream of highway bridges. Mean Cl loads ranged from 1,100 to 4,090 lb/d (pounds per day) at upstream stations and from 1,110 to 4,200 lb/d at downstream stations. Estimated mean annual Cl loads ranged from 402,000 to 1,490,000 lb/yr (pounds per year) at upstream stations and from 405,000 to 1,530,000 lb/yr at downstream stations. Mean Cl concentrations in samples collected at the three paired stations were lowest at Mill Brook at VT 117 near Essex Junction, VT (7.9 mg/L) and highest at Allen Brook at VT 2A near Essex Junction, VT (80.7 mg/L). None of the monitored Cl concentrations in the water-quality samples collected at the three paired sampling stations exceeded either of the U.S. Environmental Protection Agency's (USEPA) recommended chronic and acute Cl toxicity criteria of 230 and 860 mg/L, respectively. A fourth stream site, a small tributary draining to Alder Brook between the upstream and downstream stations, was monitored from December 2006 to November 2007. This tributary collected runoff from a state highway and an interchange before flowing through a wetlands retention basin. The mean Cl concentration in water-quality samples collected at the tributary was 449 mg/L. The USEPA recommended chronic toxicity criterion of 230 mg/L was exceeded about 65 percent of the monitoring period. The USEPA recommended acute toxicity criterion of 860 mg/L was not exceeded. Estimated Cl loads below the State highway bridges exceeded loads above the bridges at all three paired stations during both years of the study. The differences in the annual loads between the upstream and downstream stations were 0.7, 3.0 and 14 percent at Mill, Allen, and Alder Brooks, respectively. Almost all of the difference (92 percent) at Alder Brook was due to the tributary. Cl applied by the State of Vermont for deicing purposes represented less than 20 percent of the annual estimated Cl load in all 3 streams below the state highways. The highest monthly Cl loads during the first year of the study were observed in January 2006 at all three stream stations because of an early snowmelt event. The highest monthly Cl loads during the second year of the study were observed in April 2007 at all three streams during spring snowmelt and were followed by decrease in Cl loading through the summer. Generally, the relation of Cl loads to runoff was similar at all three streams. In July and October 2007, loads increased slightly with an increase in runoff, indicating that Cl in the soils and groundwater may be contributing to the Cl levels during the summer and fall, well after the road-salting season. Cl loads in all three streams appear to be due primarily to sources in the watersheds upstream of the state highway bridge where road salt was applied and (or) Cl retained in soils and streambed

3D FSE Cube and VIPR-aTR 3.0 Tesla magnetic resonance imaging predicts canine cranial cruciate ligament structural properties.

PubMed

Racette, Molly; Al saleh, Habib; Waller, Kenneth R; Bleedorn, Jason A; McCabe, Ronald P; Vanderby, Ray; Markel, Mark D; Brounts, Sabrina H; Block, Walter F; Muir, Peter

2016-03-01

Estimation of cranial cruciate ligament (CrCL) structural properties in client-owned dogs with incipient cruciate rupture would be advantageous. The objective of this study was to determine whether magnetic resonance imaging (MRI) measurement of normal CrCL volume in an ex-vivo canine model predicts structural properties. Stifles from eight dogs underwent 3.0 Tesla 3D MRI. CrCL volume and normalized median grayscale values were determined using 3D Fast Spin Echo (FSE) Cube and Vastly under-sampled Isotropic PRojection (VIPR)-alternative repetition time (aTR) sequences. Stifles were then mechanically tested. After joint laxity testing, CrCL structural properties were determined, including displacement at yield, yield load, load to failure, and stiffness. Yield load and load to failure (R(2)=0.56, P <0.01) were correlated with CrCL volume determined by VIPR-aTR. Yield load was also correlated with CrCL volume determined by 3D FSE Cube (R(2)=0.32, P <0.05). Structural properties were not related to median grayscale values. Joint laxity and CrCL stiffness were not related to MRI parameters, but displacement at yield load was related to CrCL volume for both sequences during testing (R(2)>0.57, P <0.005). In conclusion, 3D MRI offers a predictive method for estimating canine CrCL structural properties. 3D MRI may be useful for monitoring CrCL properties in clinical trials. Copyright © 2016 Elsevier Ltd. All rights reserved.

Canine stifle joint biomechanics associated with tibial plateau leveling osteotomy predicted by use of a computer model.

PubMed

Brown, Nathan P; Bertocci, Gina E; Marcellin-Little, Denis J

2014-07-01

To evaluate effects of tibial plateau leveling osteotomy (TPLO) on canine stifle joint biomechanics in a cranial cruciate ligament (CrCL)-deficient stifle joint by use of a 3-D computer model simulating the stance phase of gait and to compare biomechanics in TPLO-managed, CrCL-intact, and CrCL-deficient stifle joints. Computer simulations of the pelvic limb of a Golden Retriever. A previously developed computer model of the canine pelvic limb was used to simulate TPLO stabilization to achieve a tibial plateau angle (TPA) of 5° (baseline value) in a CrCL-deficient stifle joint. Sensitivity analysis was conducted for tibial fragment rotation of 13° to -3°. Ligament loads, relative tibial translation, and relative tibial rotation were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. TPLO with a 5° TPA converted cranial tibial translation to caudal tibial translation and increased loads placed on the remaining stifle joint ligaments, compared with results for a CrCL-intact stifle joint. Lateral collateral ligament load was similar, medial collateral ligament load increased, and caudal cruciate ligament load decreased after TPLO, compared with loads for a CrCL-deficient stifle joint. Relative tibial rotation after TPLO was similar to that of a CrCL-deficient stifle joint. Stifle joint biomechanics were affected by TPLO fragment rotation. In the model, stifle joint biomechanics were partially improved after TPLO, compared with CrCL-deficient stifle joint biomechanics, but TPLO did not fully restore CrCL-intact stifle joint biomechanics. Overrotation of the tibial fragment negatively influenced stifle joint biomechanics by increasing caudal tibial translation.

Instructional Efficiency of Tutoring in an Outreach Gene Technology Laboratory

NASA Astrophysics Data System (ADS)

Scharfenberg, Franz-Josef; Bogner, Franz X.

2013-06-01

Our research objective focused on examining the instructional efficiency of tutoring as a form of instructional change as opposed to a non-tutoring approach in an outreach laboratory. We designed our laboratory based on cognitive load (CL) theory. Altogether, 269 twelfth-graders participated in our day-long module Genetic Fingerprinting. In a quasi-experimental design, the control group ( n = 121) followed the non-tutoring approach previously used, while the treatment group ( n = 148) followed the newly developed tutoring approach. Each tutor was in charge of two student work groups and recorded the tutoring activities requested by the tutees throughout the day. We measured the students' invested mental effort (as an index of CL), cognitive achievement (in a pre-post-follow-up design), and the students' cooperation in their work groups as well as calculated the student instructional involvement (as a motivational variable). Additionally, we examined which aspects of the hands-on phases were of particular relevance to the students' invested mental effort. Unexpectedly, the combined mental effort and cognitive achievement data indicated that our implemented tutoring approach resulted in a lower instructional efficiency despite the relevance of tutoring for students' mental effort invested during the experimental phases. Most of the tutor assistance was unnecessarily requested for performing the procedural steps and using the equipment. Our results indicate an assistance dilemma and consequently underscore the necessity for effective tutor preparation in outreach laboratories.

Effect of nitro-L-arginine on electrical and mechanical responses to acetylcholine in the superior mesenteric artery from stroke-prone hypertensive rat

PubMed Central

Ghisdal, Philippe; Godfraind, Théophile; Morel, Nicole

1999-01-01

High salt diet is known to aggravate the vascular pathology in spontaneously hypertensive stroke-prone rats (SHR-SP). The aim of the present study was to assess the involvement of endothelial dysfunction in this effect. Contractile tension and membrane potential were simultaneously recorded in superior mesenteric artery rings of untreated and NaCl-loaded (1% NaCl in the drinking water) SHR-SP and normotensive Wistar Kyoto rats (WKY).In unstimulated artery, hyperpolarization evoked by acetylcholine was not different in WKY and in NaCl-loaded WKY; it was reduced in SHR-SP and further reduced in NaCl-loaded SHR-SP. Hyperpolarization was unaffected by Nω-nitro-L-arginine (L-NA) but was abolished in high-KCl solution.In noradrenaline-stimulated artery, ACh-evoked hyperpolarization and relaxation were not different in WKY and in SHR-SP. NaCl-treatment did not affect the responses to ACh in WKY but decreased maximum relaxation in SHR-SP from 93±2% to 72±7% of the contraction. In WKY, in NaCl-loaded WKY and in SHR-SP, L-NA similarly shifted the concentration-relaxation curve to ACh to the right and depressed its maximum but L-NA did not affect the hyperpolarization to ACh. In NaCl-loaded SHR-SP, L-NA blunted the effects of ACh on membrane potential and on contraction.The NO donor SNAP abolished the depolarization and the contraction evoked by noradrenaline with the same potency in WKY and in untreated SHR-SP but was more potent in NaCl-loaded SHR-SP.In KCl-contracted arteries the relaxations to ACh were not different in WKY and SHR-SP but NaCl-loaded SHR-SP were more sensitive to ACh.The results showed that NaCl-rich diet markedly reduced the L-NA-resistant responses to ACh and increased the sensitivity to NO in SHR-SP. PMID:10602331

Using Multiple Ways to Investigate Cognitive Load Theory in the Context of Physics Instruction

NASA Astrophysics Data System (ADS)

Zu, Tianlong

Cognitive load theory (CLT) (Sweller 1988, 1998, 2010) provides us a guiding framework for designing instructional materials. CLT differentiates three subtypes of cognitive load: intrinsic, extraneous, and germane cognitive load. The three cognitive loads are theorized based on the number of simultaneously processed elements in working memory. Intrinsic cognitive load depends upon the number of interacting elements in the instructional material that are related to the learning objective. Extraneous cognitive load is the mental resources allocated to processing unnecessary information which does not contribute to learning as caused by non- optimal instructional procedure. It is determined by the number of interacting elements which are not related to learning goal. Both intrinsic and extraneous load vary according to prior knowledge of learners. Germane cognitive load is indirectly related to interacting elements. It represents the cognitive resources deployed for processing intrinsic load, chunking information and constructing and automating schema. Germane cognitive load is related to level of motivation of the learner. Given this triarchic model of cognitive load and their different roles in learning activities, different learning outcomes can be expected depending upon the characteristics of the educational materials, learner characteristics, and instructional setting. In three experiments, we investigated cognitive load theory following different approaches. Given the triarchic nature of cognitive load construct, it is critical to find non- intrusive ways to measure cognitive load. In study one, we replicated and extended a previous landmark study to investigate the use of eye movements related metrics to measure the three kinds of cognitive load independently. We also collected working memory capacity of students using a cognitive operation-span task. Two of the three types of cognitive load (intrinsic and extraneous) were directly manipulated, and the third type of cognitive load (germane) was indirectly ascertained. We found that different eye-movement based parameters were most sensitive to different types of cognitive load. These results indicate that it is possible to monitor the three kinds of cognitive load separately using eye movement parameters. We also compared the up-to-date cognitive load theory model with an alternative model using a multi-level model analysis and we found that Sweller's (2010) up-to-date model is supported by our data. In educational settings, active learning based methodologies such as peer instruction have been shown to be effective in facilitating students' conceptual understanding. In study two, we discussed the effect of peer interaction on conceptual test performance of students from a cognitive load perspective. Based on the literature, a self-reported cognitive load survey was developed to measure each type of cognitive load. We found that a certain level of prior knowledge is necessary for peer interaction to work and that peer interaction is effective mainly through significantly decreasing the intrinsic load experienced by students, even though it may increase the extraneous load. In study three, we compared the effect of guided instruction in the form of worked examples using narrated-animated video solutions and semi-guided instruction using visual cues on students' performance, shift of visual attention during transfer, and extraneous cognitive load during learning. We found that multimedia video solutions can be more effective in promoting transfer performance of learners than visual cues. We also found evidence that guided instruction in the form of multimedia video solutions can decrease extraneous cognitive load of students during learning, more so than semi-guided instruction using visual cues.

Nitrogen critical loads and management alternatives for N-impacted ecosystems in California

Treesearch

M.E. Fenn; E.B. Allen; S.B. Weiss; S. Jovan; L. Geiser; G.S. Tonnesen; R.F. Johnson; L.E. Rao; B.S. Gimeno; F. Yuan; T. Meixner; A. Bytnerowicz

2010-01-01

Empirical critical loads for N deposition effects and maps showing areas projected to be in exceedance of the critical load (CL) are given for seven major vegetation types in California. Thirty-five percent of the land area for these vegetation types (99,639 km2) is estimated to be in excess of the N CL. Low CL values (3–8...

Limitations of subjective cognitive load measures in simulation-based procedural training.

PubMed

Naismith, Laura M; Cheung, Jeffrey J H; Ringsted, Charlotte; Cavalcanti, Rodrigo B

2015-08-01

The effective implementation of cognitive load theory (CLT) to optimise the instructional design of simulation-based training requires sensitive and reliable measures of cognitive load. This mixed-methods study assessed relationships between commonly used measures of total cognitive load and the extent to which these measures reflected participants' experiences of cognitive load in simulation-based procedural skills training. Two groups of medical residents (n = 38) completed three questionnaires after participating in simulation-based procedural skills training sessions: the Paas Cognitive Load Scale; the NASA Task Load Index (TLX), and a cognitive load component (CLC) questionnaire we developed to assess total cognitive load as the sum of intrinsic load (how complex the task is), extraneous load (how the task is presented) and germane load (how the learner processes the task for learning). We calculated Pearson's correlation coefficients to assess agreement among these instruments. Group interviews explored residents' perceptions about how the simulation sessions contributed to their total cognitive load. Interviews were audio-recorded, transcribed and subjected to qualitative content analysis. Total cognitive load scores differed significantly according to the instrument used to assess them. In particular, there was poor agreement between the Paas Scale and the TLX. Quantitative and qualitative findings supported intrinsic cognitive load as synonymous with mental effort (Paas Scale), mental demand (TLX) and task difficulty and complexity (CLC questionnaire). Additional qualitative themes relating to extraneous and germane cognitive loads were not reflected in any of the questionnaires. The Paas Scale, TLX and CLC questionnaire appear to be interchangeable as measures of intrinsic cognitive load, but not of total cognitive load. A more complete understanding of the sources of extraneous and germane cognitive loads in simulation-based training contexts is necessary to determine how best to measure and assess their effects on learning and performance outcomes. © 2015 John Wiley & Sons Ltd.

Selective impairment of auditory selective attention under concurrent cognitive load.

PubMed

Dittrich, Kerstin; Stahl, Christoph

2012-06-01

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 demonstrate such selective load effects for auditory selective attention. The effect of two different cognitive load tasks on two different auditory Stroop tasks was examined, and selective load effects were observed: Interference in a nonverbal-auditory Stroop task was increased under concurrent nonverbal-auditory cognitive load (compared with a no-load condition), but not under concurrent verbal-auditory cognitive load. By contrast, interference in a verbal-auditory Stroop task was increased under concurrent verbal-auditory cognitive load but not under nonverbal-auditory cognitive load. This double-dissociation pattern suggests the existence of different and separable verbal and nonverbal processing resources in the auditory domain.

Trends in the Prevalence and Disparity in Cognitive Limitations of Americans 55-69 Years Old.

PubMed

Choi, HwaJung; Schoeni, Robert F; Martin, Linda G; Langa, Kenneth M

2018-04-16

To determine whether the prevalence of cognitive limitation (CL) among Americans ages 55 to 69 years changed between 1998 and 2014, and to assess the trends in socioeconomic disparities in CL among groups defined by race/ethnicity, education, income, and wealth. Logistic regression using 1998-2014 data from the biennial Health and Retirement Study, a nationally representative data set. CL is defined as a score of 0-11 on a 27-point cognitive battery of items focused on memory. Socioeconomic status (SES) measures are classified as quartiles. In models controlling for age, gender, and previous cognitive testing, we find no significant change over time in the overall prevalence of CL, widening disparities in limitation by income and, in some cases, wealth, and improvements among non-Hispanic whites but not other racial/ethnic groups. Among people 55-69, rates of CL are many times higher for groups with lower SES than those with higher SES, and recent trends show little indication that the gaps are narrowing.

Biomechanics of an orthosis-managed cranial cruciate ligament-deficient canine stifle joint predicted by use of a computer model.

PubMed

Bertocci, Gina E; Brown, Nathan P; Mich, Patrice M

2017-01-01

OBJECTIVE To evaluate effects of an orthosis on biomechanics of a cranial cruciate ligament (CrCL)-deficient canine stifle joint by use of a 3-D quasistatic rigid-body pelvic limb computer model simulating the stance phase of gait and to investigate influences of orthosis hinge stiffness (durometer). SAMPLE A previously developed computer simulation model for a healthy 33-kg 5-year-old neutered Golden Retriever. PROCEDURES A custom stifle joint orthosis was implemented in the CrCL-deficient pelvic limb computer simulation model. Ligament loads, relative tibial translation, and relative tibial rotation in the orthosis-stabilized stifle joint (baseline scenario; high-durometer hinge]) were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. Sensitivity analysis was conducted to evaluate the influence of orthosis hinge stiffness on model outcome measures. RESULTS The orthosis decreased loads placed on the caudal cruciate and lateral collateral ligaments and increased load placed on the medial collateral ligament, compared with loads for the CrCL-intact stifle joint. Ligament loads were decreased in the orthosis-managed CrCL-deficient stifle joint, compared with loads for the CrCL-deficient stifle joint. Relative tibial translation and rotation decreased but were not eliminated after orthosis management. Increased orthosis hinge stiffness reduced tibial translation and rotation, whereas decreased hinge stiffness increased internal tibial rotation, compared with values for the baseline scenario. CONCLUSIONS AND CLINICAL RELEVANCE Stifle joint biomechanics were improved following orthosis implementation, compared with biomechanics of the CrCL-deficient stifle joint. Orthosis hinge stiffness influenced stifle joint biomechanics. An orthosis may be a viable option to stabilize a CrCL-deficient canine stifle joint.

Low cognitive load strengthens distractor interference while high load attenuates when cognitive load and distractor possess similar visual characteristics.

PubMed

Minamoto, Takehiro; Shipstead, Zach; Osaka, Naoyuki; Engle, Randall W

2015-07-01

Studies on visual cognitive load have reported inconsistent effects of distractor interference when distractors have visual characteristic that are similar to the cognitive load. Some studies have shown that the cognitive load enhances distractor interference, while others reported an attenuating effect. We attribute these inconsistencies to the amount of cognitive load that a person is required to maintain. Lower amounts of cognitive load increase distractor interference by orienting attention toward visually similar distractors. Higher amounts of cognitive load attenuate distractor interference by depleting attentional resources needed to process distractors. In the present study, cognitive load consisted of faces (Experiments 1-3) or scenes (Experiment 2). Participants performed a selective attention task in which they ignored face distractors while judging a color of a target dot presented nearby, under differing amounts of load. Across these experiments distractor interference was greater in the low-load condition and smaller in the high-load condition when the content of the cognitive load had similar visual characteristic to the distractors. We also found that when a series of judgments needed to be made, the effect was apparent for the first trial but not for the second. We further tested an involvement of working memory capacity (WMC) in the load effect (Experiment 3). Interestingly, both high and low WMC groups received an equivalent effect of the cognitive load in the first distractor, suggesting these effects are fairly automatic.

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…

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

PubMed

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

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. To develop and collect validity evidence for a revised self-report inventory that measures cognitive load types during a handoff. 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. 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). 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.

Apolipoprotein E genotype does not moderate the associations of depressive symptoms, neuroticism and allostatic load with cognitive ability and cognitive aging in the Lothian Birth Cohort 1936.

PubMed

Crook, Zander; Booth, Tom; Cox, Simon R; Corley, Janie; Dykiert, Dominika; Redmond, Paul; Pattie, Alison; Taylor, Adele M; Harris, Sarah E; Starr, John M; Deary, Ian J

2018-01-01

In this replication-and-extension study, we tested whether depressive symptoms, neuroticism, and allostatic load (multisystem physiological dysregulation) were related to lower baseline cognitive ability and greater subsequent cognitive decline in older adults, and whether these relationships were moderated by the E4 allele of the apolipoprotein E (APOE) gene. We also tested whether allostatic load mediated the relationships between neuroticism and cognitive outcomes. We used data from the Lothian Birth Cohort 1936 (n at Waves 1-3: 1,028 [M age = 69.5 y]; 820 [M duration since Wave 1 = 2.98 y]; 659 [M duration since Wave 1 = 6.74 y]). We fitted latent growth curve models of general cognitive ability (modeled using five cognitive tests) with groups of APOE E4 non-carriers and carriers. In separate models, depressive symptoms, neuroticism, and allostatic load predicted baseline cognitive ability and subsequent cognitive decline. In addition, models tested whether allostatic load mediated relationships between neuroticism and cognitive outcomes. Baseline cognitive ability had small-to-moderate negative associations with depressive symptoms (β range = -0.20 to -0.17), neuroticism (β range = -0.27 to -0.23), and allostatic load (β range = -0.11 to 0.09). Greater cognitive decline was linked to baseline allostatic load (β range = -0.98 to -0.83) and depressive symptoms (β range = -1.00 to -0.88). However, APOE E4 allele possession did not moderate the relationships of depressive symptoms, neuroticism and allostatic load with cognitive ability and cognitive decline. Additionally, the associations of neuroticism with cognitive ability and cognitive decline were not mediated through allostatic load. Our results suggest that APOE E4 status does not moderate the relationships of depressive symptoms, neuroticism, and allostatic load with cognitive ability and cognitive decline in healthy older adults. The most notable positive finding in the current research was the strong association between allostatic load and cognitive decline.

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.

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

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Aluminum chloride induces neuroinflammation, loss of neuronal dendritic spine and cognition impairment in developing rat.

PubMed

Cao, Zheng; Yang, Xu; Zhang, Haiyang; Wang, Haoran; Huang, Wanyue; Xu, Feibo; Zhuang, Cuicui; Wang, Xiaoguang; Li, Yanfei

2016-05-01

Aluminum (Al) is present in the daily life of humans, and the incidence of Al contamination increased in recent years. Long-term excessive Al intake induces neuroinflammation and cognition impairment. Neuroinflammation alter density of dendritic spine, which, in turn, influence cognition function. However, it is unknown whether increased neuroinflammation is associated with altered density of dendritic spine in Al-treated rats. In the present study, AlCl3 was orally administrated to rat at 50, 150 and 450 mg/kg for 90d. We examined the effects of AlCl3 on the cognition function, density of dendritic spine in hippocampus of CA1 and DG region and the mRNA levels of IL-1β, IL-6, TNF-α, MHC II, CX3CL1 and BNDF in developing rat. These results showed exposure to AlCl3 lead to increased mRNA levels of IL-1β, IL-6, TNF-α and MCH II, decreased mRNA levels of CX3CL1 and BDNF, decreased density of dendritic spine and impaired learning and memory in developing rat. Our results suggest AlCl3 can induce neuroinflammation that may result in loss of spine, and thereby leads to learning and memory deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

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…

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…

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…

Apolipoprotein E genotype does not moderate the associations of depressive symptoms, neuroticism and allostatic load with cognitive ability and cognitive aging in the Lothian Birth Cohort 1936

PubMed Central

Booth, Tom; Cox, Simon R.; Corley, Janie; Dykiert, Dominika; Redmond, Paul; Pattie, Alison; Taylor, Adele M.; Harris, Sarah E.; Starr, John M.; Deary, Ian J.

2018-01-01

Objectives In this replication-and-extension study, we tested whether depressive symptoms, neuroticism, and allostatic load (multisystem physiological dysregulation) were related to lower baseline cognitive ability and greater subsequent cognitive decline in older adults, and whether these relationships were moderated by the E4 allele of the apolipoprotein E (APOE) gene. We also tested whether allostatic load mediated the relationships between neuroticism and cognitive outcomes. Methods We used data from the Lothian Birth Cohort 1936 (n at Waves 1–3: 1,028 [M age = 69.5 y]; 820 [M duration since Wave 1 = 2.98 y]; 659 [M duration since Wave 1 = 6.74 y]). We fitted latent growth curve models of general cognitive ability (modeled using five cognitive tests) with groups of APOE E4 non-carriers and carriers. In separate models, depressive symptoms, neuroticism, and allostatic load predicted baseline cognitive ability and subsequent cognitive decline. In addition, models tested whether allostatic load mediated relationships between neuroticism and cognitive outcomes. Results Baseline cognitive ability had small-to-moderate negative associations with depressive symptoms (β range = -0.20 to -0.17), neuroticism (β range = -0.27 to -0.23), and allostatic load (β range = -0.11 to 0.09). Greater cognitive decline was linked to baseline allostatic load (β range = -0.98 to -0.83) and depressive symptoms (β range = -1.00 to -0.88). However, APOE E4 allele possession did not moderate the relationships of depressive symptoms, neuroticism and allostatic load with cognitive ability and cognitive decline. Additionally, the associations of neuroticism with cognitive ability and cognitive decline were not mediated through allostatic load. Conclusions Our results suggest that APOE E4 status does not moderate the relationships of depressive symptoms, neuroticism, and allostatic load with cognitive ability and cognitive decline in healthy older adults. The most notable positive finding in the current research was the strong association between allostatic load and cognitive decline. PMID:29451880

Classifying Drivers' Cognitive Load Using EEG Signals.

PubMed

Barua, Shaibal; Ahmed, Mobyen Uddin; Begum, Shahina

2017-01-01

A growing traffic safety issue is the effect of cognitive loading activities on traffic safety and driving performance. To monitor drivers' mental state, understanding cognitive load is important since while driving, performing cognitively loading secondary tasks, for example talking on the phone, can affect the performance in the primary task, i.e. driving. Electroencephalography (EEG) is one of the reliable measures of cognitive load that can detect the changes in instantaneous load and effect of cognitively loading secondary task. In this driving simulator study, 1-back task is carried out while the driver performs three different simulated driving scenarios. This paper presents an EEG based approach to classify a drivers' level of cognitive load using Case-Based Reasoning (CBR). The results show that for each individual scenario as well as using data combined from the different scenarios, CBR based system achieved approximately over 70% of classification accuracy.

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…

Mangiferin ameliorates aluminium chloride-induced cognitive dysfunction via alleviation of hippocampal oxido-nitrosative stress, proinflammatory cytokines and acetylcholinesterase level.

PubMed

Kasbe, Prajapati; Jangra, Ashok; Lahkar, Mangala

2015-01-01

Mangiferin is a phytochemical primarily present in the stem, leaves and bark of Mangifera indica. It offers neuroprotection mainly through inhibition of oxidative stress, and decreasing proinflammatory cytokines level in the brain. Aluminium has been reported to cause oxidative stress-associated damage in the brain. In the present investigation, protective effect of mangiferin against aluminium chloride (AlCl3)-induced neurotoxicity and cognitive impairment was studied in male Swiss albino mice. AlCl3 (100 mg/kg) was administered once daily through oral gavage for 42 days. Mangiferin (20 and 40 mg/kg, p.o.) was given to mice for last 21 days of the study. We found cognitive dysfunction in AlCl3-treated group, which was assessed by Morris water maze test, and novel object recognition test. AlCl3-treated group showed elevated level of oxidative stress markers, proinflammatory cytokines level and lowered hippocampal brain-derived neurotrophic factor (BDNF) content. Mangiferin (40 mg/kg) prevented the cognitive deficits, hippocampal BDNF depletion, and biochemical anomalies induced by AlCl3-treatment. In conclusion, our data demonstrated that mangiferin offers neuroprotection in AlCl3-induced neurotoxicity and it may be a potential therapeutic approach in the treatment of oxido-nitrosative stress and inflammation-associated neurotoxicity. Copyright © 2015 Elsevier GmbH. All rights reserved.

Load theory behind the wheel; perceptual and cognitive load effects.

PubMed

Murphy, Gillian; Greene, Ciara M

2017-09-01

Perceptual Load Theory has been proposed as a resolution to the longstanding early versus late selection debate in cognitive psychology. There is much evidence in support of Load Theory but very few applied studies, despite the potential for the model to shed light on everyday attention and distraction. Using a driving simulator, the effect of perceptual and cognitive load on drivers' visual search was assessed. The findings were largely in line with Load Theory, with reduced distractor processing under high perceptual load, but increased distractor processing under high cognitive load. The effect of load on driving behaviour was also analysed, with significant differences in driving behaviour under perceptual and cognitive load. In addition, the effect of perceptual load on drivers' levels of awareness was investigated. High perceptual load significantly increased inattentional blindness and deafness, for stimuli that were both relevant and irrelevant to driving. High perceptual load also increased RTs to hazards. The current study helps to advance Load Theory by illustrating its usefulness outside of traditional paradigms. There are also applied implications for driver safety and roadway design, as the current study suggests that perceptual and cognitive load are important factors in driver attention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

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…

Affective attention under cognitive load: reduced emotional biases but emergent anxiety-related costs to inhibitory control

PubMed Central

Berggren, Nick; Richards, Anne; Taylor, Joseph; Derakshan, Nazanin

2013-01-01

Trait anxiety is associated with deficits in attentional control, particularly in the ability to inhibit prepotent responses. Here, we investigated this effect while varying the level of cognitive load in a modified antisaccade task that employed emotional facial expressions (neutral, happy, and angry) as targets. Load was manipulated using a secondary auditory task requiring recognition of tones (low load), or recognition of specific tone pitch (high load). Results showed that load increased antisaccade latencies on trials where gaze toward face stimuli should be inhibited. This effect was exacerbated for high anxious individuals. Emotional expression also modulated task performance on antisaccade trials for both high and low anxious participants under low cognitive load, but did not influence performance under high load. Collectively, results (1) suggest that individuals reporting high levels of anxiety are particularly vulnerable to the effects of cognitive load on inhibition, and (2) support recent evidence that loading cognitive processes can reduce emotional influences on attention and cognition. PMID:23717273

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…

Relations between Cognitive Resources and Two Types of Germane Load for Learning

ERIC Educational Resources Information Center

Miwa, Kazuhisa; Terai, Hitoshi; Mizuno, Yosuke

2017-01-01

Cognitive load theory (CLT) distinguishes three types of cognitive loads: intrinsic, extraneous, and germane, of which the latter is generally imposed in learning activities. To examine the nature of germane cognitive load, the participants engaged in 8-by-8 Reversi games against computerized opponents. The experimental results indicated that…

The effects of individual differences, prior experience and cognitive load on the transfer of dynamic decision-making performance.

PubMed

Nicholson, Brad; O'Hare, David

2014-01-01

Situational awareness is recognised as an important factor in the performance of individuals and teams in dynamic decision-making (DDM) environments (Salmon et al. 2014 ). The present study was designed to investigate whether the scores on the WOMBAT™ Situational Awareness and Stress Tolerance Test (Roscoe and North 1980 ) would predict the transfer of DDM performance from training under different levels of cognitive load to a novel situation. Participants practised a simulated firefighting task under either low or high conditions of cognitive load and then performed a (transfer) test in an alternative firefighting environment under an intermediate level of cognitive load. WOMBAT™ test scores were a better predictor of DDM performance than scores on the Raven Matrices. Participants with high WOMBAT™ scores performed better regardless of their training condition. Participants with recent gaming experience who practised under low cognitive load showed better practice phase performance but worse transfer performance than those who practised under high cognitive load. The relationship between task experience, situational awareness ability, cognitive load and the transfer of dynamic decision-making (DDM) performance was investigated. Results showed that the WOMBAT™ test predicted transfer of DDM performance regardless of task cognitive load. The effects of cognitive load on performance varied according to previous task-relevant experience.

Cognitive load, stress, and disinhibited eating.

PubMed

Lattimore, Paul; Maxwell, Linda

2004-11-01

The impact of cognitive distraction on eating behaviour was examined in restrained and unrestrained eaters. It was predicted that restrained eaters would eat more than unrestrained eaters following high cognitive load when it involves processing of ego-threat information independent of self-reported anxiety. There were 119 female participants randomly allocated to one of four experimental conditions whereby cognitive load and ego threat were manipulated using modified colour-naming Stroop (CNS) tasks. Anxiety ratings were made prior to and following experimental tasks. After performing Stroop tasks, participants consumed snack foods ad libitum. Restrained eaters consumed significantly more food when high cognitive load was ego threatening than when it involved processing and memorisation of colour nouns and consumed significantly more than unrestrained eaters in a high cognitive load ego-threat condition. Posttask anxiety was greater than baseline across all conditions. Task difficulty was greater under high cognitive load than low cognitive load as indicated by Stroop response times. These results indicated that the escape theory of disinhibited eating is conceptually subsumed by a more generalisable limited cognitive capacity model.

Involuntary autobiographical memories are relatively more often reported during high cognitive load tasks.

PubMed

Barzykowski, Krystian; Niedźwieńska, Agnieszka

2018-01-01

Recent studies on involuntary autobiographical memories (IAMs) in daily life have shown that they are most frequently reported during daily routines (e.g. while ironing). Such studies have suggested that reporting IAMs may be influenced by the level of the ongoing task demands and availability of cognitive resources. In two studies, we investigated the effects of cognitive load on reporting IAMs. To examine the presumed cognitive load dependency of IAMs, we utilised an often-employed experimental paradigm (Schlagman & Kvavilashvili, 2008) to elicit IAMs under conditions that differed in cognitive load. When performing a vigilance task, participants had to interrupt the task each time they experienced any spontaneous mental contents and write them down. We manipulated the level of cognitive load by either instructing (cognitive load group) or not instructing (control group) participants to perform an additional demanding task. We compared the groups on the number of IAMs and other mental contents (non-IAM contents) recorded, as well as on the frequency of IAMs that was calculated as a proportion of IAMs in all mental contents reported by the participant. We expected that if reporting IAMs depends on the level of cognitive demands, then we should observe lower frequency of IAMs in the cognitive load group compared to the control group. Consistently across studies, we observed a lower number of IAMs and non-IAM contents in the cognitive load group. However, IAMs unexpectedly constituted a higher percentage of all mental contents when participants were cognitively loaded. Further implications of the cognitive load effects for IAMs research and experimental methodology are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Activation energy of the low-load NaCl transition from nanoindentation loading curves.

PubMed

Kaupp, Gerd

2014-01-01

Access to activation energies E(a) of phase transitions is opened by unprecedented analyses of temperature dependent nanoindentation loading curves. It is based on kinks in linearized loading curves, with additional support by coincidence of kink and electrical conductivity of silicon loading curves. Physical properties of B1, B2, NaCl and further phases are discussed. The normalized low-load transition energy of NaCl (Wtrans/µN) increases with temperature and slightly decreases with load. Its semi-logarithmic plot versus T obtains activation energy E(a)/µN for calculation of the transition work for all interesting temperatures and pressures. Arrhenius-type activation energy (kJ/mol) is unavailable for indentation phase transitions. The E(a) per load normalization proves insensitive to creep-on-load, which excludes normalization to depth or volume for large temperature ranges. Such phase transition E(a)/µN is unprecedented material's property and will be of practical importance for the compatibility of composite materials under impact and further shearing interactions at elevated temperatures. © 2014 Wiley Periodicals, Inc.

Development and Validation of Two Instruments Measuring Intrinsic, Extraneous, and Germane Cognitive Load.

PubMed

Klepsch, Melina; Schmitz, Florian; Seufert, Tina

2017-01-01

Cognitive Load Theory is one of the most powerful research frameworks in educational research. Beside theoretical discussions about the conceptual parts of cognitive load, the main challenge within this framework is that there is still no measurement instrument for the different aspects of cognitive load, namely intrinsic, extraneous, and germane cognitive load. Hence, the goal of this paper is to develop a differentiated measurement of cognitive load. In Study 1 ( N = 97), we developed and analyzed two strategies to measure cognitive load in a differentiated way: (1) Informed rating: We trained learners in differentiating the concepts of cognitive load, so that they could rate them in an informed way. They were asked then to rate 24 different learning situations or learning materials related to either high or low intrinsic, extraneous, or germane load. (2) Naïve rating: For this type of rating of cognitive load we developed a questionnaire with two to three items for each type of load. With this questionnaire, the same learning situations had to be rated. In the second study ( N = between 65 and 95 for each task), we improved the instrument for the naïve rating. For each study, we analyzed whether the instruments are reliable and valid, for Study 1, we also checked for comparability of the two measurement strategies. In Study 2, we conducted a simultaneous scenario based factor analysis. The informed rating seems to be a promising strategy to assess the different aspects of cognitive load, but it seems not economic and feasible for larger studies and a standardized training would be necessary. The improved version of the naïve rating turned out to be a useful, feasible, and reliable instrument. Ongoing studies analyze the conceptual validity of this measurement with up to now promising results.

Measuring cognitive load during procedural skills training with colonoscopy as an exemplar.

PubMed

Sewell, Justin L; Boscardin, Christy K; Young, John Q; Ten Cate, Olle; O'Sullivan, Patricia S

2016-06-01

Few studies have investigated cognitive factors affecting learning of procedural skills in medical education. Cognitive load theory, which focuses on working memory, is highly relevant, but methods for measuring cognitive load during procedural training are not well understood. Using colonoscopy as an exemplar, we used cognitive load theory to develop a self-report instrument to measure three types of cognitive load (intrinsic, extraneous and germane load) and to provide evidence for instrument validity. We developed the instrument (the Cognitive Load Inventory for Colonoscopy [CLIC]) using a multi-step process. It included 19 items measuring three types of cognitive load, three global rating items and demographics. We then conducted a cross-sectional survey that was administered electronically to 1061 gastroenterology trainees in the USA. Participants completed the CLIC following a colonoscopy. The two study phases (exploratory and confirmatory) each lasted for 10 weeks during the 2014-2015 academic year. Exploratory factor analysis determined the most parsimonious factor structure; confirmatory factor analysis assessed model fit. Composite measures of intrinsic, extraneous and germane load were compared across years of training and with global rating items. A total of 477 (45.0%) invitees participated (116 in the exploratory study and 361 in the confirmatory study) in 154 (95.1%) training programmes. Demographics were similar to national data from the USA. The most parsimonious factor structure included three factors reflecting the three types of cognitive load. Confirmatory factor analysis verified that a three-factor model was the best fit. Intrinsic, extraneous and germane load items had high internal consistency (Cronbach's alpha 0.90, 0.87 and 0.96, respectively) and correlated as expected with year in training and global assessment of cognitive load. The CLIC measures three types of cognitive load during colonoscopy training. Evidence of validity is provided. Although CLIC items relate to colonoscopy, the development process we detail can be used to adapt the instrument for use in other learning settings in medical education. © 2016 John Wiley & Sons Ltd.

Canadian experiences in development of critical loads for sulphur and nitrogen

Treesearch

Shaun Watmough; Julian Aherne; Paul Arp; Ian DeMerchant; Rock Ouimet

2006-01-01

Critical loads are a broad-scale modelling approach designed to assess the potential risk of pollutants to ecosystems. A description of the methodology for estimating critical loads (sulphur and nitrogen) for acid deposition (CL(A)) for upland forests in eastern Canada is presented, using a case study in central Ontario. In eastern Canada, CL(A) have been calculated...

Knowing how you are feeling depends on what's on my mind: Cognitive load and expression categorization.

PubMed

Ahmed, Lubna

2018-03-01

The ability to correctly interpret facial expressions is key to effective social interactions. People are well rehearsed and generally very efficient at correctly categorizing expressions. However, does their ability to do so depend on how cognitively loaded they are at the time? Using repeated-measures designs, we assessed the sensitivity of facial expression categorization to cognitive resources availability by measuring people's expression categorization performance during concurrent low and high cognitive load situations. In Experiment1, participants categorized the 6 basic upright facial expressions in a 6-automated-facial-coding response paradigm while maintaining low or high loading information in working memory (N = 40; 60 observations per load condition). In Experiment 2, they did so for both upright and inverted faces (N = 46; 60 observations per load and inversion condition). In both experiments, expression categorization for upright faces was worse during high versus low load. Categorization rates actually improved with increased load for the inverted faces. The opposing effects of cognitive load on upright and inverted expressions are explained in terms of a cognitive load-related dispersion in the attentional window. Overall, the findings support that expression categorization is sensitive to cognitive resources availability and moreover suggest that, in this paradigm, it is the perceptual processing stage of expression categorization that is affected by cognitive load. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

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…

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…

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…

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. ((c) 2004 APA, all rights reserved)

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. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Atmospheric deposition and critical loads for nitrogen and metals in Arctic Alaska: Review and current status

USGS Publications Warehouse

Linder, Greg L.; Brumbaugh, William G.; Neitlich, Peter; Little, Edward

2013-01-01

To protect important resources under their bureau’s purview, the United States National Park Service’s (NPS) Arctic Network (ARCN) has developed a series of “vital signs” that are to be periodically monitored. One of these vital signs focuses on wet and dry deposition of atmospheric chemicals and further, the establishment of critical load (CL) values (thresholds for ecological effects based on cumulative depositional loadings) for nitrogen (N), sulfur, and metals. As part of the ARCN terrestrial monitoring programs, samples of the feather moss Hylocomium splendens are being col- lected and analyzed as a cost-effective means to monitor atmospheric pollutant deposition in this region. Ultimately, moss data combined with refined CL values might be used to help guide future regulation of atmospheric contaminant sources potentially impacting Arctic Alaska. But first, additional long-term studies are needed to determine patterns of contaminant deposition as measured by moss biomonitors and to quantify ecosystem responses at particular loadings/ ranges of contaminants within Arctic Alaska. Herein we briefly summarize 1) current regulatory guidance related to CL values 2) derivation of CL models for N and metals, 3) use of mosses as biomonitors of atmospheric deposition and loadings, 4) preliminary analysis of vulnerabilities and risks associated with CL estimates for N, 5) preliminary analysis of existing data for characterization of CL values for N for interior Alaska and 6) implications for managers and future research needs.

Measuring cognitive load: mixed results from a handover simulation for medical students.

PubMed

Young, John Q; Irby, David M; Barilla-LaBarca, Maria-Louise; Ten Cate, Olle; O'Sullivan, Patricia S

2016-02-01

The application of cognitive load theory to workplace-based activities such as patient handovers is hindered by the absence of a measure of the different load types. This exploratory study tests a method for measuring cognitive load during handovers. The authors developed the Cognitive Load Inventory for Handoffs (CLI4H) with items for intrinsic, extraneous, and germane load. Medical students completed the measure after participating in a simulated handover. Exploratory factor and correlation analyses were performed to collect evidence for validity. Results yielded a two-factor solution for intrinsic and germane load that explained 50 % of the variance. The extraneous load items performed poorly and were removed from the model. The score for intrinsic load correlated with the Paas Cognitive Load scale (r = 0.31, p = 0.004) and was lower for students with more prior handover training (p = 0.036). Intrinsic load did not, however, correlate with performance. Germane load did not correlate with the Paas Cognitive Load scale but did correlate as expected with performance (r = 0.30, p = 0.005) and was lower for those students with more prior handover training (p = 0.03). The CLI4H yielded mixed results with some evidence for validity of the score from the intrinsic load items. The extraneous load items performed poorly and the use of only a single item for germane load limits conclusions. The instrument requires further development and testing. Study results and limitations provide guidance to future efforts to measure cognitive load during workplace-based activities, such as handovers.

Cognitive load predicts point-of-care ultrasound simulator performance.

PubMed

Aldekhyl, Sara; Cavalcanti, Rodrigo B; Naismith, Laura M

2018-02-01

The ability to maintain good performance with low cognitive load is an important marker of expertise. Incorporating cognitive load measurements in the context of simulation training may help to inform judgements of competence. This exploratory study investigated relationships between demographic markers of expertise, cognitive load measures, and simulator performance in the context of point-of-care ultrasonography. Twenty-nine medical trainees and clinicians at the University of Toronto with a range of clinical ultrasound experience were recruited. Participants answered a demographic questionnaire then used an ultrasound simulator to perform targeted scanning tasks based on clinical vignettes. Participants were scored on their ability to both acquire and interpret ultrasound images. Cognitive load measures included participant self-report, eye-based physiological indices, and behavioural measures. Data were analyzed using a multilevel linear modelling approach, wherein observations were clustered by participants. Experienced participants outperformed novice participants on ultrasound image acquisition. Ultrasound image interpretation was comparable between the two groups. Ultrasound image acquisition performance was predicted by level of training, prior ultrasound training, and cognitive load. There was significant convergence between cognitive load measurement techniques. A marginal model of ultrasound image acquisition performance including prior ultrasound training and cognitive load as fixed effects provided the best overall fit for the observed data. In this proof-of-principle study, the combination of demographic and cognitive load measures provided more sensitive metrics to predict ultrasound simulator performance. Performance assessments which include cognitive load can help differentiate between levels of expertise in simulation environments, and may serve as better predictors of skill transfer to clinical practice.

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.…

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…

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.

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.

Cognitive load, emotion, and performance in high-fidelity simulation among beginning nursing students: a pilot study.

PubMed

Schlairet, Maura C; Schlairet, Timothy James; Sauls, Denise H; Bellflowers, Lois

2015-03-01

Establishing the impact of the high-fidelity simulation environment on student performance, as well as identifying factors that could predict learning, would refine simulation outcome expectations among educators. The purpose of this quasi-experimental pilot study was to explore the impact of simulation on emotion and cognitive load among beginning nursing students. Forty baccalaureate nursing students participated in teaching simulations, rated their emotional state and cognitive load, and completed evaluation simulations. Two principal components of emotion were identified representing the pleasant activation and pleasant deactivation components of affect. Mean rating of cognitive load following simulation was high. Linear regression identiffed slight but statistically nonsignificant positive associations between principal components of emotion and cognitive load. Logistic regression identified a negative but statistically nonsignificant effect of cognitive load on assessment performance. Among lower ability students, a more pronounced effect of cognitive load on assessment performance was observed; this also was statistically non-significant. Copyright 2015, SLACK Incorporated.

Extrinsic cognitive load impairs low-level speech perception.

PubMed

Mattys, Sven L; Barden, Katharine; Samuel, Arthur G

2014-06-01

Recent research has suggested that the extrinsic cognitive load generated by performing a nonlinguistic visual task while perceiving speech increases listeners' reliance on lexical knowledge and decreases their capacity to perceive phonetic detail. In the present study, we asked whether this effect is accounted for better at a lexical or a sublexical level. The former would imply that cognitive load directly affects lexical activation but not perceptual sensitivity; the latter would imply that increased lexical reliance under cognitive load is only a secondary consequence of imprecise or incomplete phonetic encoding. Using the phoneme restoration paradigm, we showed that perceptual sensitivity decreases (i.e., phoneme restoration increases) almost linearly with the effort involved in the concurrent visual task. However, cognitive load had only a minimal effect on the contribution of lexical information to phoneme restoration. We concluded that the locus of extrinsic cognitive load on the speech system is perceptual rather than lexical. Mechanisms by which cognitive load increases tolerance to acoustic imprecision and broadens phonemic categories were discussed.

Using chloride and other ions to trace sewage and road salt in the Illinois Waterway

USGS Publications Warehouse

Kelly, W.R.; Panno, S.V.; Hackley, Keith C.; Hwang, H.-H.; Martinsek, A.T.; Markus, M.

2010-01-01

Chloride concentrations in waterways of northern USA are increasing at alarming rates and road salt is commonly assumed to be the cause. However, there are additional sources of Cl- in metropolitan areas, such as treated wastewater (TWW) and water conditioning salts, which may be contributing to Cl- loads entering surface waters. In this study, the potential sources of Cl- and Cl- loads in the Illinois River Basin from the Chicago area to the Illinois River's confluence with the Mississippi River were investigated using halide data in stream samples and published Cl- and river discharge data. The investigation showed that road salt runoff and TWW from the Chicago region dominate Cl- loads in the Illinois Waterway, defined as the navigable sections of the Illinois River and two major tributaries in the Chicago region. Treated wastewater discharges at a relatively constant rate throughout the year and is the primary source of Cl- and other elements such as F- and B. Chloride loads are highest in the winter and early spring as a result of road salt runoff which can increase Cl- concentrations by up to several hundred mg/L. Chloride concentrations decrease downstream in the Illinois Waterway due to dilution, but are always elevated relative to tributaries downriver from Chicago. The TWW component is especially noticeable downstream under low discharge conditions during summer and early autumn when surface drainage is at a minimum and agricultural drain tiles are not flowing. Increases in population, urban and residential areas, and roadways in the Chicago area have caused an increase in the flux of Cl- from both road salt and TWW. Chloride concentrations have been increasing in the Illinois Waterway since around 1960 at a rate of about 1 mg/L/a. The increase is largest in the winter months due to road salt runoff. Shallow groundwater Cl- concentrations are also increasing, potentially producing higher base flow concentrations. Projected increases in population and urbanization over the next several decades suggest that the trend of increasing Cl- concentrations and loads will continue. Given the susceptibility of aquatic ecosystems to increasing Cl- concentrations, especially short-term spikes following snow melts, deleterious effects on riverine ecosystems would be expected. ?? 2010 Elsevier Ltd. All rights reserved.

Extrinsic Cognitive Load Impairs Spoken Word Recognition in High- and Low-Predictability Sentences.

PubMed

Hunter, Cynthia R; Pisoni, David B

Listening effort (LE) induced by speech degradation reduces performance on concurrent cognitive tasks. However, a converse effect of extrinsic cognitive load on recognition of spoken words in sentences has not been shown. The aims of the present study were to (a) examine the impact of extrinsic cognitive load on spoken word recognition in a sentence recognition task and (b) determine whether cognitive load and/or LE needed to understand spectrally degraded speech would differentially affect word recognition in high- and low-predictability sentences. Downstream effects of speech degradation and sentence predictability on the cognitive load task were also examined. One hundred twenty young adults identified sentence-final spoken words in high- and low-predictability Speech Perception in Noise sentences. Cognitive load consisted of a preload of short (low-load) or long (high-load) sequences of digits, presented visually before each spoken sentence and reported either before or after identification of the sentence-final word. LE was varied by spectrally degrading sentences with four-, six-, or eight-channel noise vocoding. Level of spectral degradation and order of report (digits first or words first) were between-participants variables. Effects of cognitive load, sentence predictability, and speech degradation on accuracy of sentence-final word identification as well as recall of preload digit sequences were examined. In addition to anticipated main effects of sentence predictability and spectral degradation on word recognition, we found an effect of cognitive load, such that words were identified more accurately under low load than high load. However, load differentially affected word identification in high- and low-predictability sentences depending on the level of sentence degradation. Under severe spectral degradation (four-channel vocoding), the effect of cognitive load on word identification was present for high-predictability sentences but not for low-predictability sentences. Under mild spectral degradation (eight-channel vocoding), the effect of load was present for low-predictability sentences but not for high-predictability sentences. There were also reliable downstream effects of speech degradation and sentence predictability on recall of the preload digit sequences. Long digit sequences were more easily recalled following spoken sentences that were less spectrally degraded. When digits were reported after identification of sentence-final words, short digit sequences were recalled more accurately when the spoken sentences were predictable. Extrinsic cognitive load can impair recognition of spectrally degraded spoken words in a sentence recognition task. Cognitive load affected word identification in both high- and low-predictability sentences, suggesting that load may impact both context use and lower-level perceptual processes. Consistent with prior work, LE also had downstream effects on memory for visual digit sequences. Results support the proposal that extrinsic cognitive load and LE induced by signal degradation both draw on a central, limited pool of cognitive resources that is used to recognize spoken words in sentences under adverse listening conditions.

Assessing effect of meditation on cognitive workload using EEG signals

NASA Astrophysics Data System (ADS)

Jadhav, Narendra; Manthalkar, Ramchandra; Joshi, Yashwant

2017-06-01

Recent research suggests that meditation affects the structure and function of the brain. Cognitive load can be handled in effective way by the meditators. EEG signals are used to quantify cognitive load. The research of investigating effect of meditation on cognitive workload using EEG signals in pre and post-meditation is an open problem. The subjects for this study are young healthy 11 engineering students from our institute. The focused attention meditation practice is used for this study. EEG signals are recorded at the beginning of meditation and after four weeks of regular meditation using EMOTIV device. The subjects practiced meditation daily 20 minutes for 4 weeks. The 7 level arithmetic additions of single digit (low level) to three digits with carry (high level) are presented as cognitive load. The cognitive load indices such as arousal index, performance enhancement, neural activity, load index, engagement, and alertness are evaluated in pre and post meditation. The cognitive indices are improved in post meditation data. Power Spectral Density (PSD) feature is compared between pre and post-meditation across all subjects. The result hints that the subjects were handling cognitive load without stress (ease of cognitive functioning increased for the same load) after 4 weeks of meditation.

Deliberation's blindsight: how cognitive load can improve judgments.

PubMed

Hoffmann, Janina A; von Helversen, Bettina; Rieskamp, Jörg

2013-06-01

Multitasking poses a major challenge in modern work environments by putting the worker under cognitive load. Performance decrements often occur when people are under high cognitive load because they switch to less demanding--and often less accurate--cognitive strategies. Although cognitive load disturbs performance over a wide range of tasks, it may also carry benefits. In the experiments reported here, we showed that judgment performance can increase under cognitive load. Participants solved a multiple-cue judgment task in which high performance could be achieved by using a similarity-based judgment strategy but not by using a more demanding rule-based judgment strategy. Accordingly, cognitive load induced a shift to a similarity-based judgment strategy, which consequently led to more accurate judgments. By contrast, shifting to a similarity-based strategy harmed judgments in a task best solved by using a rule-based strategy. These results show how important it is to consider the cognitive strategies people rely on to understand how people perform in demanding work environments.

Cognitive load effects on early visual perceptual processing.

PubMed

Liu, Ping; Forte, Jason; Sewell, David; Carter, Olivia

2018-05-01

Contrast-based early visual processing has largely been considered to involve autonomous processes that do not need the support of cognitive resources. However, as spatial attention is known to modulate early visual perceptual processing, we explored whether cognitive load could similarly impact contrast-based perception. We used a dual-task paradigm to assess the impact of a concurrent working memory task on the performance of three different early visual tasks. The results from Experiment 1 suggest that cognitive load can modulate early visual processing. No effects of cognitive load were seen in Experiments 2 or 3. Together, the findings provide evidence that under some circumstances cognitive load effects can penetrate the early stages of visual processing and that higher cognitive function and early perceptual processing may not be as independent as was once thought.

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…

The effect of cognitive load and patient race on physicians' decisions to prescribe opioids for chronic low back pain: a randomized trial.

PubMed

Burgess, Diana J; Phelan, Sean; Workman, Michael; Hagel, Emily; Nelson, David B; Fu, Steven S; Widome, Rachel; van Ryn, Michelle

2014-06-01

To test the hypothesis that racial biases in opioid prescribing would be more likely under high levels of cognitive load, defined as the amount of mental activity imposed on working memory, which may come from environmental factors such as stressful conditions, chaotic workplace, staffing insufficiency, and competing demands, one's own psychological or physiological state, as well as from demands inherent in the task at hand. Two (patient race: White vs Black) by two (cognitive load: low vs high) between-subjects factorial design. Ninety-eight primary care physicians from the Veterans Affairs Healthcare System. Web-based experimental study. Physicians were randomly assigned to read vignettes about either a Black or White patient, under low vs high cognitive load, and to indicate their likelihood of prescribing opioids. High cognitive load was induced by having physicians perform a concurrent task under time pressure. There was a three-way interaction between patient race, cognitive load, and physician gender on prescribing decisions (P = 0.034). Hypotheses were partially confirmed. Male physicians were less likely to prescribe opioids for Black than White patients under high cognitive load (12.5% vs 30.0%) and were more likely to prescribe opioids for Black than White patients under low cognitive load (30.8% vs 10.5%). By contrast, female physicians were more likely to prescribe opioids for Black than White patients in both conditions, with greater racial differences under high (39.1% vs 15.8%) vs low cognitive load (28.6% vs 21.7%). Physician gender affected the way in which patient race and cognitive load influenced decisions to prescribe opioids for chronic pain. Future research is needed to further explore the potential effects of physician gender on racial biases in pain treatment, and the effects of physician cognitive load on pain treatment. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

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.

Development and Validation of Two Instruments Measuring Intrinsic, Extraneous, and Germane Cognitive Load

PubMed Central

Klepsch, Melina; Schmitz, Florian; Seufert, Tina

2017-01-01

Cognitive Load Theory is one of the most powerful research frameworks in educational research. Beside theoretical discussions about the conceptual parts of cognitive load, the main challenge within this framework is that there is still no measurement instrument for the different aspects of cognitive load, namely intrinsic, extraneous, and germane cognitive load. Hence, the goal of this paper is to develop a differentiated measurement of cognitive load. In Study 1 (N = 97), we developed and analyzed two strategies to measure cognitive load in a differentiated way: (1) Informed rating: We trained learners in differentiating the concepts of cognitive load, so that they could rate them in an informed way. They were asked then to rate 24 different learning situations or learning materials related to either high or low intrinsic, extraneous, or germane load. (2) Naïve rating: For this type of rating of cognitive load we developed a questionnaire with two to three items for each type of load. With this questionnaire, the same learning situations had to be rated. In the second study (N = between 65 and 95 for each task), we improved the instrument for the naïve rating. For each study, we analyzed whether the instruments are reliable and valid, for Study 1, we also checked for comparability of the two measurement strategies. In Study 2, we conducted a simultaneous scenario based factor analysis. The informed rating seems to be a promising strategy to assess the different aspects of cognitive load, but it seems not economic and feasible for larger studies and a standardized training would be necessary. The improved version of the naïve rating turned out to be a useful, feasible, and reliable instrument. Ongoing studies analyze the conceptual validity of this measurement with up to now promising results. PMID:29201011

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…

Effects of Cognitive Load on Driving Performance: The Cognitive Control Hypothesis.

PubMed

Engström, Johan; Markkula, Gustav; Victor, Trent; Merat, Natasha

2017-08-01

The objective of this paper was to outline an explanatory framework for understanding effects of cognitive load on driving performance and to review the existing experimental literature in the light of this framework. Although there is general consensus that taking the eyes off the forward roadway significantly impairs most aspects of driving, the effects of primarily cognitively loading tasks on driving performance are not well understood. Based on existing models of driver attention, an explanatory framework was outlined. This framework can be summarized in terms of the cognitive control hypothesis: Cognitive load selectively impairs driving subtasks that rely on cognitive control but leaves automatic performance unaffected. An extensive literature review was conducted wherein existing results were reinterpreted based on the proposed framework. It was demonstrated that the general pattern of experimental results reported in the literature aligns well with the cognitive control hypothesis and that several apparent discrepancies between studies can be reconciled based on the proposed framework. More specifically, performance on nonpracticed or inherently variable tasks, relying on cognitive control, is consistently impaired by cognitive load, whereas the performance on automatized (well-practiced and consistently mapped) tasks is unaffected and sometimes even improved. Effects of cognitive load on driving are strongly selective and task dependent. The present results have important implications for the generalization of results obtained from experimental studies to real-world driving. The proposed framework can also serve to guide future research on the potential causal role of cognitive load in real-world crashes.

Learning STEM through Integrative Visual Representations

ERIC Educational Resources Information Center

Virk, Satyugjit Singh

2013-01-01

Previous cognitive models of memory have not comprehensively taken into account the internal cognitive load of chunking isolated information and have emphasized the external cognitive load of visual presentation only. Under the Virk Long Term Working Memory Multimedia Model of cognitive load, drawing from the Cowan model, students presented with…

Comparison among model estimates of critical loads of acidic deposition using different sources and scales of input data

Treesearch

T.C. McDonnell; B.J. Cosby; T.J. Sullivan; S.G. McNulty; E.C. Cohen

2010-01-01

The critical load (CL) of acidic atmospheric deposition represents the load of acidity deposited from the atmosphere to the earth’s surface at which harmful acidification effects on sensitive biological receptors are thought to occur. In this study, the CL for forest soils was estimated for 27 watersheds throughout the United States using a steady-state mass balance...

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. © 2016 Wiley Periodicals, Inc.

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 (c) 2017 APA, all rights reserved).

Spatial release of cognitive load measured in a dual-task paradigm in normal-hearing and hearing-impaired listeners.

PubMed

Xia, Jing; Nooraei, Nazanin; Kalluri, Sridhar; Edwards, Brent

2015-04-01

This study investigated whether spatial separation between talkers helps reduce cognitive processing load, and how hearing impairment interacts with the cognitive load of individuals listening in multi-talker environments. A dual-task paradigm was used in which performance on a secondary task (visual tracking) served as a measure of the cognitive load imposed by a speech recognition task. Visual tracking performance was measured under four conditions in which the target and the interferers were distinguished by (1) gender and spatial location, (2) gender only, (3) spatial location only, and (4) neither gender nor spatial location. Results showed that when gender cues were available, a 15° spatial separation between talkers reduced the cognitive load of listening even though it did not provide further improvement in speech recognition (Experiment I). Compared to normal-hearing listeners, large individual variability in spatial release of cognitive load was observed among hearing-impaired listeners. Cognitive load was lower when talkers were spatially separated by 60° than when talkers were of different genders, even though speech recognition was comparable in these two conditions (Experiment II). These results suggest that a measure of cognitive load might provide valuable insight into the benefit of spatial cues in multi-talker environments.

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…

Sodium chloride promotes tissue inflammation via osmotic stimuli in subtotal-nephrectomized mice.

PubMed

Sakata, Fumiko; Ito, Yasuhiko; Mizuno, Masashi; Sawai, Akiho; Suzuki, Yasuhiro; Tomita, Takako; Tawada, Mitsuhiro; Tanaka, Akio; Hirayama, Akiyoshi; Sagara, Akihiro; Wada, Takashi; Maruyama, Shoichi; Soga, Tomoyoshi; Matsuo, Seiichi; Imai, Enyu; Takei, Yoshifumi

2017-04-01

Chronic inflammation, which is often associated with high all-cause and cardiovascular mortality, is prevalent in patients with renal failure; however, the precise mechanisms remain unclear. High-salt intake was reported to induce lymphangiogenesis and autoimmune diseases via osmotic stimuli with accumulation of sodium or chloride. In addition, sodium was recently reported to be stored in the extremities of dialysis patients. We studied the effects and mechanisms of high salt loading on tissue and systemic inflammation in subtotal-nephrectomized mice (5/6Nx) and in cultured cells. Macrophage infiltration in the peritoneal wall (P<0.001), heart (P<0.05) and para-aortic tissues (P<0.001) was significantly higher in 5/6Nx with salt loading (5/6Nx/NaCl) than in 5/6Nx without salt loading (5/6Nx/Water); however, there were no significant differences in blood pressure and renal function between the groups. Tissue interleukin-6, monocyte chemotactic protein-1 (MCP-1), serum- and glucocorticoid-inducible kinase 1 (Sgk1) and tonicity-responsive enhancer binding protein (TonEBP) mRNA were significantly elevated in the peritoneal wall and heart with 5/6Nx/NaCl when compared with 5/6Nx/Water. Sodium was stored in the abdominal wall, exerting high-osmotic conditions. Reversal of salt loading reduced macrophage infiltration associated with decreased TonEBP in 5/6Nx/NaCl. Macrophage infiltration associated with fibrosis induced by salt loading was decreased in the 5/6Nx/NaCl/CC chemokine receptor 2 (CCR2, receptor of MCP-1)-deficient mice when compared with 5/6Nx/NaCl/Wild mice, suggesting that CCR2 is required for macrophage infiltration in 5/6Nx with NaCl loading. In cultured mesothelial cells and cardiomyocytes, culture media with high NaCl concentration induced MCP-1, Sgk1 and TonEBP mRNA, all of which were suppressed by TonEBP siRNA, indicating that both MCP-1 and Sgk1 are downstream of TonEBP. Our study indicates that high NaCl intake induces MCP-1 expression leading to macrophage infiltration via the TonEBP-MCP-1 pathway in 5/6Nx/NaCl mice, and that TonEBP has a central role in inflammation in patients with renal failure taking high salt.

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

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

NASA Astrophysics Data System (ADS)

Hsieh, Ya-Hui; Tsai, Chin-Chung

2014-06-01

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 used to ascertain the students' scientific epistemic beliefs, information commitments, and cognitive load experience. Structural equation modeling was then used to analyze the moderating effect of cognitive load, with the results revealing its significant moderating effect. The relationships between sophisticated scientific epistemic beliefs and the advanced evaluative standards used by the students were significantly stronger for low than for high cognitive load students. Moreover, considering the searching strategies that the students used, the relationships between sophisticated scientific epistemic beliefs and advanced searching strategies were also stronger for low than for high cognitive load students. However, for the high cognitive load students, only one of the sophisticated scientific epistemic belief dimensions was found to positively associate with advanced evaluative standard dimensions.

Blood Glucose, Diet-Based Glycemic Load and Cognitive Aging Among Dementia-Free Older Adults

PubMed Central

Andel, Ross; McEvoy, Cathy; Dahl Aslan, Anna K.; Finkel, Deborah; Pedersen, Nancy L.

2015-01-01

Background. Although evidence indicates that Type II Diabetes is related to abnormal brain aging, the influence of elevated blood glucose on long-term cognitive change is unclear. In addition, the relationship between diet-based glycemic load and cognitive aging has not been extensively studied. The focus of this study was to investigate the influence of diet-based glycemic load and blood glucose on cognitive aging in older adults followed for up to 16 years. Methods. Eight-hundred and thirty-eight cognitively healthy adults aged ≥50 years (M = 63.1, SD = 8.3) from the Swedish Adoption/Twin Study of Aging were studied. Mixed effects growth models were utilized to assess overall performance and change in general cognitive functioning, perceptual speed, memory, verbal ability, and spatial ability as a function of baseline blood glucose and diet-based glycemic load. Results. High blood glucose was related to poorer overall performance on perceptual speed as well as greater rates of decline in general cognitive ability, perceptual speed, verbal ability, and spatial ability. Diet-based glycemic load was related to poorer overall performance in perceptual speed and spatial ability. Conclusion. Diet-based glycemic load and, in particular, elevated blood glucose appear important for cognitive performance/cognitive aging. Blood glucose control (perhaps through low glycemic load diets) may be an important target in the detection and prevention of age-related cognitive decline. PMID:25149688

Cognitive benefits of lithium chloride in APP/PS1 mice are associated with enhanced brain clearance of β-amyloid.

PubMed

Pan, Yijun; Short, Jennifer L; Newman, Stephanie A; Choy, Kwok H C; Tiwari, Durgesh; Yap, Christopher; Senyschyn, Danielle; Banks, William A; Nicolazzo, Joseph A

2018-05-01

Epidemiological evidence suggests that people with bipolar disorder prescribed lithium exhibit a lower risk of Alzheimer's disease (AD) relative to those prescribed other mood-stabilizing medicines. Lithium chloride (LiCl) reduces brain β-amyloid (Aβ) levels, and the brain clearance of Aβ is reduced in AD. Therefore, the purpose of this study was to assess whether the cognitive benefits of LiCl are associated with enhanced brain clearance of exogenously-administered Aβ. The brain clearance of intracerebroventricularly (icv) administered 125 I-Aβ 42 was assessed in male Swiss outbred mice administered daily oral NaCl or LiCl (300 mg/kg for 21 days). LiCl exhibited a 31% increase in the brain clearance of 125 I-Aβ 42 over 10 min, which was associated with a 1.6-fold increase in brain microvascular expression of the blood-brain barrier efflux transporter low density lipoprotein receptor-related protein 1 (LRP1) and increased cerebrospinal fluid (CSF) bulk-flow. 8-month-old female wild type (WT) and APP/PS1 mice were also administered daily NaCl or LiCl for 21 days, which was followed by cognitive assessment by novel object recognition and water maze, and measurement of soluble Aβ 42 , plaque-associated Aβ 42 , and brain efflux of 125 I-Aβ 42 . LiCl treatment restored the long-term spatial memory deficit observed in APP/PS1 mice as assessed by the water maze (back to similar levels of escape latency as WT mice), but the short-term memory deficit remained unaffected by LiCl treatment. While LiCl did not affect plaque-associated Aβ 42 , soluble Aβ 42 levels were reduced by 49.9% in APP/PS1 mice receiving LiCl. The brain clearance of 125 I-Aβ 42 decreased by 27.8% in APP/PS1 mice, relative to WT mice, however, LiCl treatment restored brain 125 I-Aβ 42 clearance in APP/PS1 mice to a rate similar to that observed in WT mice. These findings suggest that the cognitive benefits and brain Aβ 42 lowering effects of LiCl are associated with enhanced brain clearance of Aβ 42 , possibly via brain microvascular LRP1 upregulation and increased CSF bulk-flow, identifying a novel mechanism of protection by LiCl for the treatment of AD. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

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…

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…

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…

The effect of implementing cognitive load theory-based design principles in virtual reality simulation training of surgical skills: a randomized controlled trial.

PubMed

Andersen, Steven Arild Wuyts; Mikkelsen, Peter Trier; Konge, Lars; Cayé-Thomasen, Per; Sørensen, Mads Sølvsten

2016-01-01

Cognitive overload can inhibit learning, and cognitive load theory-based instructional design principles can be used to optimize learning situations. This study aims to investigate the effect of implementing cognitive load theory-based design principles in virtual reality simulation training of mastoidectomy. Eighteen novice medical students received 1 h of self-directed virtual reality simulation training of the mastoidectomy procedure randomized for standard instructions (control) or cognitive load theory-based instructions with a worked example followed by a problem completion exercise (intervention). Participants then completed two post-training virtual procedures for assessment and comparison. Cognitive load during the post-training procedures was estimated by reaction time testing on an integrated secondary task. Final-product analysis by two blinded expert raters was used to assess the virtual mastoidectomy performances. Participants in the intervention group had a significantly increased cognitive load during the post-training procedures compared with the control group (52 vs. 41 %, p  = 0.02). This was also reflected in the final-product performance: the intervention group had a significantly lower final-product score than the control group (13.0 vs. 15.4, p  < 0.005). Initial instruction using worked examples followed by a problem completion exercise did not reduce the cognitive load or improve the performance of the following procedures in novices. Increased cognitive load when part tasks needed to be integrated in the post-training procedures could be a possible explanation for this. Other instructional designs and methods are needed to lower the cognitive load and improve the performance in virtual reality surgical simulation training of novices.

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

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

PubMed

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.

Short-Term Effects of Different Loading Schemes in Fitness-Related Resistance Training.

PubMed

Eifler, Christoph

2016-07-01

Eifler, C. Short-term effects of different loading schemes in fitness-related resistance training. J Strength Cond Res 30(7): 1880-1889, 2016-The purpose of this investigation was to analyze the short-term effects of different loading schemes in fitness-related resistance training and to identify the most effective loading method for advanced recreational athletes. The investigation was designed as a longitudinal field-test study. Two hundred healthy mature subjects with at least 12 months' experience in resistance training were randomized in 4 samples of 50 subjects each. Gender distribution was homogenous in all samples. Training effects were quantified by 10 repetition maximum (10RM) and 1 repetition maximum (1RM) testing (pre-post-test design). Over a period of 6 weeks, a standardized resistance training protocol with 3 training sessions per week was realized. Testing and training included 8 resistance training exercises in a standardized order. The following loading schemes were randomly matched to each sample: constant load (CL) with constant volume of repetitions, increasing load (IL) with decreasing volume of repetitions, decreasing load (DL) with increasing volume of repetitions, daily changing load (DCL), and volume of repetitions. For all loading schemes, significant strength gains (p < 0.001) could be noted for all resistance training exercises and both dependent variables (10RM, 1RM). In all cases, DCL obtained significantly higher strength gains (p < 0.001) than CL, IL, and DL. There were no significant differences in strength gains between CL, IL, and DL. The present data indicate that resistance training following DCL is more effective for advanced recreational athletes than CL, IL, or DL. Considering that DCL is widely unknown in fitness-related resistance training, the present data indicate, there is potential for improving resistance training in commercial fitness clubs.

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

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

PubMed

Pecchinenda, Anna; 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.

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

Preliminary assessment of chloride concentrations, loads, and yields in selected watersheds along the Interstate 95 corridor, southeastern Connecticut, 2008-09

USGS Publications Warehouse

Brown, Craig J.; Mullaney, John R.; Morrison, Jonathan; Mondazzi, Remo

2011-01-01

Water-quality conditions were assessed to evaluate potential effects of road-deicer applications on stream-water quality in four watersheds along Interstate 95 (I-95) in southeastern Connecticut from November 1, 2008, through September 30, 2009. This preliminary study is part of a four-year cooperative study by the U.S. Geological Survey (USGS), the Federal Highway Administration (FHWA), and the Connecticut Department of Transportation (ConnDOT). Streamflow and water quality were studied at four watersheds?Four Mile River, Oil Mill Brook, Stony Brook, and Jordan Brook. Water-quality samples were collected and specific conductance was measured continuously at paired water-quality monitoring sites upstream and downstream from I-95. Specific conductance values were related to chloride (Cl) concentrations to assist in determining the effects of road-deicing operations on the levels of Cl in the streams. Streamflow and water-quality data were compared with weather data and with the timing, amount, and composition of deicers applied to state highways. Grab samples were collected during winter stormwater-runoff events, such as winter storms or periods of rain or warm temperatures in which melting takes place, and periodically during the spring and summer. Cl concentrations at the eight water-quality monitoring sites were well below the U.S. Environmental Protection Agency (USEPA) recommended chronic and acute Cl toxicity criteria of 230 and 860 milligrams per liter (mg/L), respectively. Specific conductance and estimated Cl concentrations in streams, particularly at sites downstream from I-95, peaked during discharge events in the winter and early spring as a result of deicers applied to roads and washed off by stormwater or meltwater. During winter storms, deicing activities, or subsequent periods of melting, specific conductance and estimated Cl concentrations peaked as high as 703 microsiemens per centimeter (?S/cm) and 160 mg/L at the downstream sites. During most of the spring and summer, specific conductance and estimated Cl concentrations decreased during discharge events because the low-ionic strength of stormwater had a diluting effect on stream-water quality. However, peaks in specific conductance and estimated Cl concentrations at Jordan Brook and Stony Brook corresponded to peaks in streamflow well after winter snow or ice events; these delayed peaks in Cl concentration likely resulted from deicing salts that remained in melting snow piles and (or) that were flushed from soils and shallow groundwater, then discharged downstream. Cl loads in streams generally were highest in the winter and early spring. The estimated load for the period of record at the four monitoring sites downstream from I-95 ranged from 0.33 ton per day (ton/d) at the Stony Brook watershed to 0.59 ton/d at the Jordan Brook watershed. The Cl yields ranged from 0.07 ton per day per square mile (ton/d/)mi2) at Oil Mill Brook, one of the least developed watersheds, to 0.21 (ton/d)/mi2) at Jordan Brook, the watershed with the highest percentage of urban development and impervious surfaces. The median estimates of Cl load from atmospheric deposition ranged from 11 to 19 tons, and contributed 4.3 to 7.1 percent of the Cl load in streamflow from the watershed areas. A comparison of the Cl load input and output estimates indicates that less Cl is leaving the watersheds than is entering through atmospheric deposition and application of deicers. The lag time between introduction of Cl to the watershed and transport to the stream, and uncertainty in the load estimates may be the reasons for this discrepancy. In addition, estimates of direct infiltration of Cl to groundwater from atmospheric deposition, deicer applications, and septic-tank drainfields to groundwater were outside the scope of the November 2008 to September 2009 assessment. However, increased concentrations of ions were observed between upstream and downstream sites and could result from deicer appli

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 article Recall of an aversive autobiographical memory is a cognitive demanding task. The vividness and emotionality of an aversive memory decrease more after recall with eye movements than after only recall or only cognitive effort (i.e., recall of an irrelevant memory with eye movements). The cognitive load of recalling the memory does not immediately reduce after recall with eye movements compared to only recall or only cognitive effort. Intervention duration is positively related to memory effects. PMID:27387845

Analysis of collaborative communication for linguistic cues of cognitive load.

PubMed

Khawaja, M Asif; Chen, Fang; Marcus, Nadine

2012-08-01

Analyses of novel linguistic and grammatical features, extracted from transcribed speech of people working in a collaborative environment, were performed for cognitive load measurement Prior studies have attempted to assess users' cognitive load with several measures, but most of them are intrusive and disrupt normal task flow. An effective measurement of people's cognitive load can help improve their performance by deploying appropriate output and support strategies accordingly. The authors studied 33 members of bushfire management teams working collaboratively in computerized incident control rooms and involved in complex bushfire management tasks. The participants' communication was analyzed for some novel linguistic features as potential indices of cognitive load, which included sentence length, use of agreement and disagreement phrases, and use of personal pronouns, including both singular and plural pronoun types. Results showed users' different linguistic and grammatical patterns with various cognitive load levels. Specifically, with high load, people spoke more and used longer sentences, used more words that indicated disagreement with other team members, and exhibited increased use of plural personal pronouns and decreased use of singular pronouns. The article provides encouraging evidence for the use of linguistic and grammatical analysis for measuring users' cognitive load and proposes some novel features as cognitive load indices. The proposed approach may be applied to many data-intense and safety-critical task scenarios, such as emergency management departments, for example, bushfire or traffic incident management centers; air traffic control rooms; and call centers, where speech is used as part of everyday tasks.

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…

Cognitive Load Theory and the Role of Learner Experience: An Abbreviated Review for Educational Practitioners

ERIC Educational Resources Information Center

Artino, Anthony R., Jr.

2008-01-01

The purpose of this review is to provide educational practitioners with a brief overview of cognitive load theory (CLT) and its major implications for learning. To achieve this objective, the article includes a short description of human cognitive architecture as conceived by cognitive load theorists. Following this overview, the article provides…

The effect of platinum precursor concentrations on chlorine sensing characteristics of platinum nanoparticles-loaded single walled carbon nanotubes

NASA Astrophysics Data System (ADS)

Choi, Sun-Woo; Byun, Young Tae

2018-03-01

The correlation between platinum (Pt) functionalization and chlorine (Cl2) sensing capability in single-walled carbon nanotubes (SWCNTs) was investigated. Utilizing a photoreduction technique via ultraviolet (UV) irradiation, the Pt nanoparticles (NPs) with various diameters of 7-80 nm, which were controlled by Pt precursor concentrations, were successfully functionalized on the sidewalls of SWCNTs. The discrete Pt NP-loaded SWCNTs exhibited significantly enhanced response value (-(ΔR/R0) × 100 = 33.8%) for 1 ppm Cl2 at room temperature (25 °C) compared with that (no response) of pure SWCNTs. On the other hand, in case of continuous Pt NP-loaded SWCNTs, Cl2 sensing capabilities were significantly degraded. The Cl2 sensing capabilities of fabricated sensors tended to correlate with geometric configurations of the catalytic Pt NPs on the sidewalls of SWCNTs, due to differences in the electron pathway.

Is Hand Selection Modulated by Cognitive-perceptual Load?

PubMed

Liang, Jiali; Wilkinson, Krista; Sainburg, Robert L

2018-01-15

Previous studies proposed that selecting which hand to use for a reaching task appears to be modulated by a factor described as "task difficulty". However, what features of a task might contribute to greater or lesser "difficulty" in the context of hand selection decisions has yet to be determined. There has been evidence that biomechanical and kinematic factors such as movement smoothness and work can predict patterns of selection across the workspace, suggesting a role of predictive cost analysis in hand-selection. We hypothesize that this type of prediction for hand-selection should recruit substantial cognitive resources and thus should be influenced by cognitive-perceptual loading. We test this hypothesis by assessing the role of cognitive-perceptual loading on hand selection decisions, using a visual search task that presents different levels of difficulty (cognitive-perceptual load), as established in previous studies on overall response time and efficiency of visual search. Although the data are necessarily preliminary due to small sample size, our data suggested an influence of cognitive-perceptual load on hand selection, such that the dominant hand was selected more frequently as cognitive load increased. Interestingly, cognitive-perceptual loading also increased cross-midline reaches with both hands. Because crossing midline is more costly in terms of kinematic and kinetic factors, our findings suggest that cognitive processes are normally engaged to avoid costly actions, and that the choice not-to-cross midline requires cognitive resources. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

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.

Multi-functional polyelectrolyte multilayer films: combining mechanical resistance, biodegradability and bioactivity

PubMed Central

Schneider, Aurore; Vodouhê, Constant; Richert, Ludovic; Francius, Gregory; Le Guen, Erell; Schaaf, Pierre; Voegel, Jean-Claude; Frisch, Benoît; Picart, Catherine

2008-01-01

Cross-linked polyelectrolyte multilayer films (CL PEM) have an increased rigidity and are mechanically more resistant than native (e.g. uncrosslinked) films. However, they are still biodegradable, which make them interesting candidates for biomedical applications. In this study, CL PEM films have been explored for their multifunctional properties as i) mechanically resistant ii) biodegradable and iii) bioactive films. Toward this end, we investigated drug loading into CL chitosan/hyaluronan (CHI/HA) and poly(L-lysine)/hyaluronan (PLL/HA) films by simple diffusion of the drugs. Sodium diclofenac and paclitaxel were chosen as model drugs and were successfully loaded into the films. The effect of varying the number of layers in the (CHI/HA) films as well as the cross-linker concentration on diclofenac loading were studied. Diclofenac was released from the film in about ten hours. Paclitaxel was also found to diffuse within CL films. Its activity was maintained after loading in the CL films and cellular viability could be reduced by about 55% over three days. Such simple approach may be applied to other types of cross-linked films and to other drugs. These results prove that it is possible to design multifunctional multilayer films that combine mechanical resistance, biodegradability and bioactivity properties into a single PEM architecture. PMID:17206799

Tuning down the hedonic brain: Cognitive load reduces neural responses to high-calorie food pictures in the nucleus accumbens.

PubMed

van Dillen, Lotte F; van Steenbergen, Henk

2018-06-01

The present research examined whether cognitive load modulates the neural processing of appetitive, high-calorie food stimuli. In a functional magnetic resonance imaging (fMRI) study, participants quickly categorized high-calorie and low-calorie food pictures versus object pictures as edible or inedible while they concurrently performed a digit-span task that varied between low and high cognitive load (memorizing six digits vs. one digit). In line with predictions, the digit-span task engaged the dorsolateral prefrontal cortex (DLPFC) when cognitive load was high compared to low. Moreover, exposure to high-calorie compared to low-calorie food pictures led to increased activation in the nucleus accumbens (NAcc), but only when cognitive load was low and not when it was high. In addition, connectivity analyses showed that load altered the functional coupling between NAcc and right DLPFC during presentation of the high-calorie versus low-calorie food pictures. Together, these findings indicate that loading the cognitive system moderates hedonic brain responses to high-calorie food pictures via interactions between NAcc and DLPFC. Our findings are consistent with the putative cognitive nature of food motivation. Implications for future research are discussed.

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

2017-06-01

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.

High Tumor Penetration of Paclitaxel Loaded pH Sensitive Cleavable Liposomes by Depletion of Tumor Collagen I in Breast Cancer.

PubMed

Zhang, Li; Wang, Yang; Yang, Yuting; Liu, Yayuan; Ruan, Shaobo; Zhang, Qianyu; Tai, Xiaowei; Chen, Jiantao; Xia, Tai; Qiu, Yue; Gao, Huile; He, Qin

2015-05-13

The network of collagen I in tumors could prevent the penetration of drugs loaded in nanoparticles, and this would lead to impaired antitumor efficacy. In this study, free losartan (an angiotensin inhibitor) was injected before treatment to reduce the level of collagen I, which could facilitate the penetration of nanoparticles. Then the pH-sensitive cleavable liposomes (Cl-Lip) were injected subsequently to exert the antitumor effect. The Cl-Lip was constituted by PEG(5K)-Hydrazone-PE and DSPE-PEG(2K)-R8. When the Cl-Lip reached to the tumor site by the enhanced permeability and retention (EPR) effect, PEG(5K)-Hydrazone-PE was hydrolyzed from the Cl-Lip under the low extra-cellular pH conditions of tumors, then the R8 peptide was exposed, and finally liposomes could be internalized into tumor cells by the mediation of R8 peptide. In vitro experiments showed both the cellular uptake of Cl-Lip by 4T1 cells and cytotoxicity of paclitaxel loaded Cl-Lip (PTX-Cl-Lip) were pH sensitive. In vivo experiments showed the Cl-Lip had a good tumor targeting ability. After depletion of collagen I, Cl-Lip could penetrate into the deep place of tumors, the tumor accumulation of Cl-Lip was further increased by 22.0%, and the oxygen distributed in tumor tissues was also enhanced. The antitumor study indicated free losartan in combination with PTX-Cl-Lip (59.8%) was more effective than injection with PTX-Cl-Lip only (37.8%) in 4T1 tumor bearing mice. All results suggested that depletion of collagen I by losartan dramatically increased the penetration of PTX-Cl-Lip and combination of free losartan and PTX-CL-Lip could lead to better antitumor efficacy of chemical drugs. Thus, the combination strategy might be a promising tactic for better treatment of solid tumors with a high level of collagen I.

Modeling salinization and recovery of road salt-impacted lakes in temperate regions based on long-term monitoring of Lake George, New York (USA) and its drainage basin.

PubMed

Sutherland, J W; Norton, S A; Short, J W; Navitsky, C

2018-05-08

Road salt mitigates winter highway icing but accumulates in watershed soils and receiving waters, affecting soil chemistry and physical, biological, and ecological processes. Despite efforts to reduce salt loading in watersheds, accumulated cations and Cl - continue to impact tributaries and lakes, and the recovery process is not well understood. Lake George, New York (USA) is typical of many temperate lakes at risk for elevated Cl - concentrations from winter deicing; the lake salt concentration increased by ~3.4% year -1 since 1980. Here, we evaluated the ionic composition in Finkle Brook, a major watershed draining to Lake George, studied intermittently since 1970 and typical of other salt-impacted Lake George tributaries. Salt loading in the Lake George basin since the 1940s displaced cations from exchange sites in basin soils; these desorbed cations follow a simple ion-exchange model, with lower sodium and higher calcium, magnesium and potassium fluxes in runoff. Reduced salt application in the Finkle Brook watershed during the low-snow winter of 2015-2016 led to a 30-40% decline of Cl - and base cations in the tributary, implying a Cl - soil half-life of 1-2 years. We developed a conceptual model that describes cation behavior in runoff from a watershed that received road salt loading over a long period of time, and then recovery following reduced salt loading. Next, we developed a dynamic model estimating time to steady-state for Cl - in Lake George with road salt loading starting in 1940, calibrating the model with tributary runoff and lake chemistry data from 1970 and 1980, respectively, and forecasting Cl - concentrations in Lake George based on various scenarios of salt loading and soil retention of Cl - . Our Lake George models are readily adaptable to other temperate lakes with drainage basins where road salt is applied during freezing conditions and paved roads cover a portion of the watershed. Copyright © 2018 Elsevier B.V. All rights reserved.

Poor phonetic perceivers are affected by cognitive load when resolving talker variability

PubMed Central

Antoniou, Mark; Wong, Patrick C. M.

2015-01-01

Speech training paradigms aim to maximise learning outcomes by manipulating external factors such as talker variability. However, not all individuals may benefit from such manipulations because subject-external factors interact with subject-internal ones (e.g., aptitude) to determine speech perception and/or learning success. In a previous tone learning study, high-aptitude individuals benefitted from talker variability, whereas low-aptitude individuals were impaired. Because increases in cognitive load have been shown to hinder speech perception in mixed-talker conditions, it has been proposed that resolving talker variability requires cognitive resources. This proposal leads to the hypothesis that low-aptitude individuals do not use their cognitive resources as efficiently as those with high aptitude. Here, high- and low-aptitude subjects identified pitch contours spoken by multiple talkers under high and low cognitive load conditions established by a secondary task. While high-aptitude listeners outperformed low-aptitude listeners across load conditions, only low-aptitude listeners were impaired by increased cognitive load. The findings suggest that low-aptitude listeners either have fewer available cognitive resources or are poorer at allocating attention to the signal. Therefore, cognitive load is an important factor when considering individual differences in speech perception and training paradigms. PMID:26328675

Poor phonetic perceivers are affected by cognitive load when resolving talker variability.

PubMed

Antoniou, Mark; Wong, Patrick C M

2015-08-01

Speech training paradigms aim to maximise learning outcomes by manipulating external factors such as talker variability. However, not all individuals may benefit from such manipulations because subject-external factors interact with subject-internal ones (e.g., aptitude) to determine speech perception and/or learning success. In a previous tone learning study, high-aptitude individuals benefitted from talker variability, whereas low-aptitude individuals were impaired. Because increases in cognitive load have been shown to hinder speech perception in mixed-talker conditions, it has been proposed that resolving talker variability requires cognitive resources. This proposal leads to the hypothesis that low-aptitude individuals do not use their cognitive resources as efficiently as those with high aptitude. Here, high- and low-aptitude subjects identified pitch contours spoken by multiple talkers under high and low cognitive load conditions established by a secondary task. While high-aptitude listeners outperformed low-aptitude listeners across load conditions, only low-aptitude listeners were impaired by increased cognitive load. The findings suggest that low-aptitude listeners either have fewer available cognitive resources or are poorer at allocating attention to the signal. Therefore, cognitive load is an important factor when considering individual differences in speech perception and training paradigms.

Real-time closed-loop control of cognitive load in neurological patients during robot-assisted gait training.

PubMed

Koenig, Alexander; Novak, Domen; Omlin, Ximena; Pulfer, Michael; Perreault, Eric; Zimmerli, Lukas; Mihelj, Matjaz; Riener, Robert

2011-08-01

Cognitively challenging training sessions during robot-assisted gait training after stroke were shown to be key requirements for the success of rehabilitation. Despite a broad variability of cognitive impairments amongst the stroke population, current rehabilitation environments do not adapt to the cognitive capabilities of the patient, as cognitive load cannot be objectively assessed in real-time. We provided healthy subjects and stroke patients with a virtual task during robot-assisted gait training, which allowed modulating cognitive load by adapting the difficulty level of the task. We quantified the cognitive load of stroke patients by using psychophysiological measurements and performance data. In open-loop experiments with healthy subjects and stroke patients, we obtained training data for a linear, adaptive classifier that estimated the current cognitive load of patients in real-time. We verified our classification results via questionnaires and obtained 88% correct classification in healthy subjects and 75% in patients. Using the pre-trained, adaptive classifier, we closed the cognitive control loop around healthy subjects and stroke patients by automatically adapting the difficulty level of the virtual task in real-time such that patients were neither cognitively overloaded nor under-challenged. © 2011 IEEE

Effect of load carriage and natural terrain conditions on cognitive performance in desert environments.

PubMed

Bhattacharyya, Debojyoti; Pal, Madhusudan; Chatterjee, Tirthankar; Majumdar, Dhurjati

2017-10-01

Correct decision making is a critical component of cognitive performance of a soldier, which may be influenced by the load carriage and terrain conditions during their deployment in desert environment. The present study was aimed to investigate the effects of loads and terrain conditions on the cognitive performance in a group of twelve healthy heat acclimatized infantry soldiers under natural desert environment. The soldiers participated in a 10min walking trial during carrying no load and also carrying 10.7, 21.4 and 30kg at two terrain conditions viz., sandy and hard. We studied attention, memory and executive function, which are having immense functional importance in military operations. Standardized cognitive test battery was applied to the participants after carrying each magnitude of load at each terrain. Baseline cognitive performance was recorded on a separate day and was compared with the performances recorded after the load carriage trials. An attempt was made to reveal the relationship between physiological workload (relative workload) and cognitive performance at the point of completion of load carriage trials. Load, terrains and load×terrain interaction did not produce any significant effect (p>0.05) on the cognitive performance. Attention and relative workload were found significantly correlated at hard terrain under no load, 21.4kg and 30kg. Significant correlation was found between executive function and relative workload at hard terrain under no load. Carrying upto 30kg load for 10min at 3.5-4kmph walking speed resulted in improvement in attention at sandy terrain, decrement in memory at both sandy and hard terrains and improvement in executive function at sandy terrain. Copyright © 2017 Elsevier Inc. All rights reserved.

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

2017-10-01

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.

Empirical and simulated critical loads for nitrogen deposition in California mixed conifer forests

Treesearch

M.E. Fenn; S. Jovan; F. Yuan; L. Geiser; T. Meixner; B.S. Gimeno

2008-01-01

Empirical critical loads (CL) for N deposition were determined from changes in epiphytic lichen communities, elevated NO3 leaching in streamwater, and reduced fine root biomass in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) at sites with varying N deposition. The CL for lichen community impacts of 3.1 kg ha-1 year

Describing the interplay between anxiety and cognition: From impaired performance under low cognitive load to reduced anxiety under high load

PubMed Central

Vytal, Katherine; Cornwell, Brian; Arkin, Nicole; Grillon, Christian

2012-01-01

Anxiety impairs the ability to think and concentrate, suggesting that the interaction between emotion and cognition may elucidate the debilitating nature of pathological anxiety. Using a verbal n-back task that parametrically modulated cognitive load, we explored the effect of experimentally-induced anxiety on task performance and the startle reflex. Findings suggest there is a crucial inflection point between moderate and high cognitive load, where resources shift from anxious apprehension to focus on task demands. Specifically, we demonstrate that anxiety impairs performance under low-load, but is reduced when subjects engage in a difficult task that occupies executive resources. We propose a two-component model of anxiety that describes a cognitive mechanism behind performance impairment and an automatic response that supports sustained anxiety-potentiated startle. Implications for therapeutic interventions and emotional pathology are discussed. PMID:22332819

Blood glucose, diet-based glycemic load and cognitive aging among dementia-free older adults.

PubMed

Seetharaman, Shyam; Andel, Ross; McEvoy, Cathy; Dahl Aslan, Anna K; Finkel, Deborah; Pedersen, Nancy L

2015-04-01

Although evidence indicates that Type II Diabetes is related to abnormal brain aging, the influence of elevated blood glucose on long-term cognitive change is unclear. In addition, the relationship between diet-based glycemic load and cognitive aging has not been extensively studied. The focus of this study was to investigate the influence of diet-based glycemic load and blood glucose on cognitive aging in older adults followed for up to 16 years. Eight-hundred and thirty-eight cognitively healthy adults aged ≥50 years (M = 63.1, SD = 8.3) from the Swedish Adoption/Twin Study of Aging were studied. Mixed effects growth models were utilized to assess overall performance and change in general cognitive functioning, perceptual speed, memory, verbal ability, and spatial ability as a function of baseline blood glucose and diet-based glycemic load. High blood glucose was related to poorer overall performance on perceptual speed as well as greater rates of decline in general cognitive ability, perceptual speed, verbal ability, and spatial ability. Diet-based glycemic load was related to poorer overall performance in perceptual speed and spatial ability. Diet-based glycemic load and, in particular, elevated blood glucose appear important for cognitive performance/cognitive aging. Blood glucose control (perhaps through low glycemic load diets) may be an important target in the detection and prevention of age-related cognitive decline. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

PubMed Central

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

2017-01-01

Smoking cessation failures are frequently thought to reflect poor top-down regulatory control over behavior. Previous studies suggest 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. The current study 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 performance of daily smokers (n=17) would be most impaired when high load was paired with smoking distractors. Results demonstrated a main effect of load, with decreased accuracy under high, compared to low, cognitive load. Surprisingly, an interaction revealed 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 relative to 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. 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. PMID:27012714

Emotion, cognitive load and learning outcomes during simulation training.

PubMed

Fraser, Kristin; Ma, Irene; Teteris, Elise; Baxter, Heather; Wright, Bruce; McLaughlin, Kevin

2012-11-01

Simulation training has emerged as an effective way to complement clinical training of medical students. Yet outcomes from simulation training must be considered suboptimal when 25-30% of students fail to recognise a cardiac murmur on which they were trained 1 hour previously. There are several possible explanations for failure to improve following simulation training, which include the impact of heightened emotions on learning and cognitive overload caused by interactivity with high-fidelity simulators. This study was conducted to assess emotion during simulation training and to explore the relationships between emotion and cognitive load, and diagnostic performance. We trained 84 Year 1 medical students on a scenario of chest pain caused by symptomatic aortic stenosis. After training, students were asked to rate their emotional state and cognitive load. We then provided training on a dyspnoea scenario before asking participants to diagnose the murmur in which they had been trained (aortic stenosis) and a novel murmur (mitral regurgitation). We used factor analysis to identify the principal components of emotion, and then studied the associations between these components of emotion and cognitive load and diagnostic performance. We identified two principal components of emotion, which we felt represented invigoration and tranquillity. Both of these were associated with cognitive load with adjusted regression coefficients of 0.63 (95% confidence interval [CI] 0.28-0.99; p = 0.001) and - 0.44 (95% CI - 0.77 to - 0.10; p = 0.009), respectively. We found a significant negative association between cognitive load and the odds of subsequently identifying the trained murmur (odds ratio 0.27, 95% CI 0.11-0.67; p = 0.004). We found that increased invigoration and reduced tranquillity during simulation training were associated with increased cognitive load, and that the likelihood of correctly identifying a trained murmur declined with increasing cognitive load. Further studies are needed to evaluate the impact on performance of strategies to alter emotion and cognitive load during simulation training. © Blackwell Publishing Ltd 2012.

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

PubMed

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

2016-01-01

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. 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). 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. 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. 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.

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. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of a Stelar-Localized Transport Protein That Facilitates Root-to-Shoot Transfer of Chloride in Arabidopsis.

PubMed

Li, Bo; Byrt, Caitlin; Qiu, Jiaen; Baumann, Ute; Hrmova, Maria; Evrard, Aurelie; Johnson, Alexander A T; Birnbaum, Kenneth D; Mayo, Gwenda M; Jha, Deepa; Henderson, Sam W; Tester, Mark; Gilliham, Mathew; Roy, Stuart J

2016-02-01

Under saline conditions, higher plants restrict the accumulation of chloride ions (Cl(-)) in the shoot by regulating their transfer from the root symplast into the xylem-associated apoplast. To identify molecular mechanisms underpinning this phenomenon, we undertook a transcriptional screen of salt stressed Arabidopsis (Arabidopsis thaliana) roots. Microarrays, quantitative RT-PCR, and promoter-GUS fusions identified a candidate gene involved in Cl(-) xylem loading from the Nitrate transporter 1/Peptide Transporter family (NPF2.4). This gene was highly expressed in the root stele compared to the cortex, and its expression decreased after exposure to NaCl or abscisic acid. NPF2.4 fused to fluorescent proteins, expressed either transiently or stably, was targeted to the plasma membrane. Electrophysiological analysis of NPF2.4 in Xenopus laevis oocytes suggested that NPF2.4 catalyzed passive Cl(-) efflux out of cells and was much less permeable to NO3(-). Shoot Cl(-) accumulation was decreased following NPF2.4 artificial microRNA knockdown, whereas it was increased by overexpression of NPF2.4. Taken together, these results suggest that NPF2.4 is involved in long-distance transport of Cl(-) in plants, playing a role in the loading and the regulation of Cl(-) loading into the xylem of Arabidopsis roots during salinity stress. © 2016 American Society of Plant Biologists. All Rights Reserved.

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…

A preliminary psychometric evaluation of the eight-item cognitive load scale.

PubMed

Pignatiello, Grant A; Tsivitse, Emily; Hickman, Ronald L

2018-04-01

The aim of this article is to report the psychometric properties of the eight-item cognitive load scale. According to cognitive load theory, the formatting and delivery of healthcare education influences the degree to which patients and/or family members can engage their working memory systems for learning. However, despite its relevance, cognitive load has not yet been evaluated among surrogate decision makers exposed to electronic decision support for healthcare decisions. To date, no psychometric analyses of instruments evaluating cognitive load have been reported within healthcare settings. A convenience sample of 62 surrogate decision makers for critically ill patients were exposed to one of two healthcare decision support interventions were recruited from four intensive care units at a tertiary medical center in Northeast Ohio. Participants were administered a battery of psychosocial instruments and the eight-item cognitive load scale (CLS). The CLS demonstrated a bidimensional factor structure with acceptable discriminant validity and internal consistency reliability (Cronbach's α = 0.75 and 0.89). The CLS is a psychometrically sound instrument that may be used in the evaluation of decision support among surrogate decision makers of the critically ill. The authors recommend application of the cognitive load scale in the evaluation and development of healthcare education and interventions. Copyright © 2018 Elsevier Inc. All rights reserved.

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. Copyright © 2016 Elsevier B.V. All rights reserved.

Cognitive Load Theory: implications for medical education: AMEE Guide No. 86.

PubMed

Young, John Q; Van Merrienboer, Jeroen; Durning, Steve; Ten Cate, Olle

2014-05-01

Cognitive Load Theory (CLT) builds upon established models of human memory that include the subsystems of sensory, working and long-term memory. Working memory (WM) can only process a limited number of information elements at any given time. This constraint creates a "bottleneck" for learning. CLT identifies three types of cognitive load that impact WM: intrinsic load (associated with performing essential aspects of the task), extraneous load (associated with non-essential aspects of the task) and germane load (associated with the deliberate use of cognitive strategies that facilitate learning). When the cognitive load associated with a task exceeds the learner's WM capacity, performance and learning is impaired. To facilitate learning, CLT researchers have developed instructional techniques that decrease extraneous load (e.g. worked examples), titrate intrinsic load to the developmental stage of the learner (e.g. simplify task without decontextualizing) and ensure that unused WM capacity is dedicated to germane load, i.e. cognitive learning strategies. A number of instructional techniques have been empirically tested. As learners' progress, curricula must also attend to the expertise-reversal effect. Instructional techniques that facilitate learning among early learners may not help and may even interfere with learning among more advanced learners. CLT has particular relevance to medical education because many of the professional activities to be learned require the simultaneous integration of multiple and varied sets of knowledge, skills and behaviors at a specific time and place. These activities possess high "element interactivity" and therefore impose a cognitive load that may surpass the WM capacity of the learner. Applications to various medical education settings (classroom, workplace and self-directed learning) are explored.

Neurocognition, functional competence and self-reported functional impairment in psychometrically defined schizotypy.

PubMed

Xavier, Shannon; Best, Michael W; Schorr, Emily; Bowie, Christopher R

2015-01-01

Schizotypy is phenologically and genetically related to schizophrenia-spectrum illness. Previous studies find cognitive function to be mildly impaired, but specific impairments and their relationship to functioning are not well understood. In this study, we sought to examine how cognitive load affects performance in schizotypy and to examine whether impairments might manifest in functional capacity and quality of life. Undergraduate students were screened for abnormally high levels of schizotypy (N = 72) and compared to those without psychopathology (N = 80) on a standard battery of neuropsychological tests, cognitive tests with varying cognitive load, functional capacity measures and quality of life. The high schizotypy group did not differ from controls on traditional measures of neuropsychological functioning, but an interaction of group by cognitive load was observed, where those with schizotypy manifested a greater decline in performance as information processing load was parametrically increased. Differences in functioning were observed and cognitive impairment was associated with impaired functioning. Cognitive and functional impairment can be observed in those with high schizotypal traits who are non-treatment seeking. The sensitivity of cognitive tests to impairment in this population might be a function of their ability to parametrically increase cognitive load.

Influence of learner knowledge and case complexity on handover accuracy and cognitive load: results from a simulation study.

PubMed

Young, John Q; van Dijk, Savannah M; O'Sullivan, Patricia S; Custers, Eugene J; Irby, David M; Ten Cate, Olle

2016-09-01

The handover represents a high-risk event in which errors are common and lead to patient harm. A better understanding of the cognitive mechanisms of handover errors is essential to improving handover education and practice. This paper reports on an experiment conducted to study the effects of learner knowledge, case complexity (i.e. cases with or without a clear diagnosis) and their interaction on handover accuracy and cognitive load. Participants were 52 Dutch medical students in Years 2 and 6. The experiment employed a repeated-measures design with two explanatory variables: case complexity (simple or complex) as the within-subject variable, and learner knowledge (as indicated by illness script maturity) as the between-subject covariate. The dependent variables were handover accuracy and cognitive load. Each participant performed a total of four simulated handovers involving two simple cases and two complex cases. Higher illness script maturity predicted increased handover accuracy (p < 0.001) and lower cognitive load (p = 0.007). Case complexity did not independently affect either outcome. For handover accuracy, there was no interaction between case complexity and illness script maturity. For cognitive load, there was an interaction effect between illness script maturity and case complexity, indicating that more mature illness scripts reduced cognitive load less in complex cases than in simple cases. Students with more mature illness scripts performed more accurate handovers and experienced lower cognitive load. For cognitive load, these effects were more pronounced in simple than complex cases. If replicated, these findings suggest that handover curricula and protocols should provide support that varies according to the knowledge of the trainee. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

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

PubMed

Grassmann, Mariel; Vlemincx, Elke; von Leupoldt, Andreas; Mittelstädt, Justin M; Van den Bergh, Omer

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.

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

Impact of Cognitive Loading on Postural Control in Parkinson’s Disease With Freezing of Gait

PubMed Central

Buated, Wannipat; Lolekha, Praween; Hidaka, Shohei; Fujinami, Tsutomu

2016-01-01

Objective:To assess standing balance in Parkinson’s disease (PD) patients with and without freezing of gait (FOG) during cognitive loading. Method:A balance assessment with cognitive loading, reading (RE) and counting backward (CB), was performed by the Nintendo Wii Fit in 60 PD patients (Hoehn and Yahr stages 1-3) at Thammasat University Hospital, Thailand. The participants were grouped into FOG and non-FOG according to the Freezing of Gait–Questionnaire (FOG-Q) scores. The center of pressure (CoP) in terms of path length (PL), sway area (SA), root mean square (RMS), medio-lateral (ML), and antero-posterior (AP) were analyzed. Results:Significant increases of PL were observed in both groups of PD patients during cognitive loading (p < .001). Meanwhile, the increased differences of PL during cognitive loading in PD-FOG were larger than in PD-non-FOG. The ML displacement during counting backward was significantly increased in PD-FOG (p = .012). Conclusion:Cognitive loading influenced standing balance and postural sway of PD patients. The effects were more prominent in PD-FOG. These findings represent the interactions between cognitive function, postural control, and FOG in PD. PMID:28680941

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.

Advanced zinc-doped adhesives for high performance at the resin-carious dentin interface.

PubMed

Toledano, Manuel; Osorio, Raquel; Osorio, Estrella; García-Godoy, Franklin; Toledano-Osorio, Manuel; Aguilera, Fátima S

2016-09-01

The purpose of this study was to evaluate the remineralization ability of an etch-and-rinse Zn-doped resin applied on caries-affected dentin (CAD). CAD surfaces were subjected to: (i) 37% phosphoric acid (PA) or (ii) 0.5M ethylenediaminetetraacetic acid (EDTA). 10wt% ZnO nanoparticles or 2wt% ZnCl2 were added into the adhesive Single Bond (SB), to create the following groups: PA+SB, PA+SB-ZnO, PA+SB-ZnCl2, EDTA+SB, EDTA+SB-ZnO, EDTA+SB-ZnCl2. Bonded interfaces were submitted to mechanical loading or stored during 24h. Remineralization of the bonded interfaces was studied by AFM nano-indentation (hardness and Young׳s modulus), Raman spectroscopy [mapping with principal component analysis (PCA), and hierarchical cluster analysis (HCA)] and Masson׳s trichrome staining technique. Dentin samples treated with PA+SB-ZnO attained the highest values of nano-mechanical properties. Load cycling increased both mineralization and crystallographic maturity at the interface; this effect was specially noticed when using ZnCl2-doped resin in EDTA-treated carious dentin. Crosslinking attained higher frequencies indicating better conformation and organization of collagen in specimens treated with PA+SB-ZnO, after load cycling. Trichrome staining technique depicted a deeper demineralized dentin fringe that became reduced after loading, and it was not observable in EDTA+SB groups. Multivariate analysis confirmed de homogenizing effect of load cycling in the percentage of variances, traces of centroids and distribution of clusters, especially in specimens treated with EDTA+SB-ZnCl2. Copyright © 2016 Elsevier Ltd. All rights reserved.

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. © 2015 American Association of Anatomists.

No negative priming without cognitive control.

PubMed

de Fockert, Jan W; Mizon, Guy A; D'Ubaldo, Mariangela

2010-12-01

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 affect the negative priming effect produced when a distractor from 1 trial appears as a target on the next trial. We measured priming on trials that involved either high or low cognitive control load, and found that under high control load, negative priming was eliminated, and could even be reversed to positive priming, suggesting that the negative priming effect depends on the availability of cognitive control resources.

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)…

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…

Measurement of Cognitive Load in Multimedia Learning: A Comparison of Different Objective Measures

ERIC Educational Resources Information Center

Korbach, Andreas; Brünken, Roland; Park, Babette

2017-01-01

Different indicators are interesting for analyzing human learning processes. Recent studies analyze learning performance in combination with cognitive load, as an indicator for learners' invested mental effort. In order to compare different measures of cognitive load research, the present study uses three different objective methods and one…

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…

Cognitive Load Imposed by Ultrasound-Facilitated Teaching Does Not Adversely Affect Gross Anatomy Learning Outcomes

ERIC Educational Resources Information Center

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

2017-01-01

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…

The Influence of a Pedagogical Agent on Learners' Cognitive Load

ERIC Educational Resources Information Center

Schroeder, Noah L.

2017-01-01

According to cognitive load theorists, the incorporation of extraneous features, such as pedagogical agents, into the learning environment can introduce extraneous cognitive load and thus interfere with learning outcome scores. In this study, the influence of a pedagogical agent's presence in an instructional video was compared to a video that did…

Behavioral and fMRI evidence of the differing cognitive load of domain-specific assessments.

PubMed

Howard, S J; Burianová, H; Ehrich, J; Kervin, L; Calleia, A; Barkus, E; Carmody, J; Humphry, S

2015-06-25

Standards-referenced educational reform has increased the prevalence of standardized testing; however, whether these tests accurately measure students' competencies has been questioned. This may be due to domain-specific assessments placing a differing domain-general cognitive load on test-takers. To investigate this possibility, functional magnetic resonance imaging (fMRI) was used to identify and quantify the neural correlates of performance on current, international standardized methods of spelling assessment. Out-of-scanner testing was used to further examine differences in assessment results. Results provide converging evidence that: (a) the spelling assessments differed in the cognitive load placed on test-takers; (b) performance decreased with increasing cognitive load of the assessment; and (c) brain regions associated with working memory were more highly activated during performance of assessments that were higher in cognitive load. These findings suggest that assessment design should optimize the cognitive load placed on test-takers, to ensure students' results are an accurate reflection of their true levels of competency. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

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.

Static and Dynamic Compaction of CL-20 Powders

NASA Astrophysics Data System (ADS)

Cooper, Marcia; Brundage, Aaron; Dudley, Evan

2009-06-01

Hexanitrohexaazaisowurtzitane (CL-20) powders were compacted under quasi-static and dynamic loading conditions. A uniaxial compression apparatus quasi-statically compressed the powders to 90% theoretical maximum density with applied stresses up to 0.5 GPa. Dynamic compaction measurements using low-density pressings (62-70% theoretical maximum density) were obtained in a single-stage gas gun at impact velocities between 0.17-0.70 km/s. Experiments were conducted in a reverse ballistic arrangement in which the CL-20 ladened projectile impacted a target consisting of an aluminized window. VISAR-measured particle velocities at the explosive-window interface determined the shock Hugoniot states for pressures up to 0.9 GPa. The powder compaction behavior is found to be stiffer under dynamic loading than under quasi-static loading. Additional gas gun tests were conducted in which the low-density CL-20 pressings were confined within a target cup by the aluminized window. This arrangement enabled temporal measurement of the transmitted wave profiles in which elastic wave precursors were observed.

Effects of Motion in the Far Peripheral Visual Field on Cognitive Test Performance and Cognitive Load.

PubMed

Bevilacqua, Andy; Paas, Fred; Krigbaum, Genomary

2016-04-01

Cognitive load theory posits that limited attention is in actuality a limitation in working memory resources. The load theory of selective attention and cognitive control sees the interplay between attention and awareness as separate modifying functions that act on working memory. Reconciling the theoretical differences in these two theories has important implications for learning. Thirty-nine adult participants performed a cognitively demanding test, with and without movement in the far peripheral field. Although the results for movement effects on cognitive load in this experiment were not statistically significant, men spent less time on the cognitive test in the peripheral movement condition than in the conditions without peripheral movement. No such difference was found for women. The implications of these results and recommendations for future research that extends the present study are presented. © The Author(s) 2016.

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.

Measuring Cognitive Load in Embodied Learning Settings.

PubMed

Skulmowski, Alexander; Rey, Günter Daniel

2017-01-01

In recent years, research on embodied cognition has inspired a number of studies on multimedia learning and instructional psychology. However, in contrast to traditional research on education and multimedia learning, studies on embodied learning (i.e., focusing on bodily action and perception in the context of education) in some cases pose new problems for the measurement of cognitive load. This review provides an overview over recent studies on embodied learning in which cognitive load was measured using surveys, behavioral data, or physiological measures. The different methods are assessed in terms of their success in finding differences of cognitive load in embodied learning scenarios. At the same time, we highlight the most important challenges for researchers aiming to include these measures into their study designs. The main issues we identified are: (1) Subjective measures must be appropriately phrased to be useful for embodied learning; (2) recent findings indicate potentials as well as problematic aspects of dual-task measures; (3) the use of physiological measures offers great potential, but may require mobile equipment in the context of embodied scenarios; (4) meta-cognitive measures can be useful extensions of cognitive load measurement for embodied learning.

Response-Conflict Moderates the Cognitive Control of Episodic and Contextual Load in Older Adults

PubMed Central

Eich, Teal S.; Rakitin, Brian C.

2016-01-01

Objectives: Decline in cognitive control is one of the primary cognitive changes in normal aging. Reaching a consensus regarding the nature of these age-related changes, however, is complicated by the complexity of cognitive control as a construct. Methods: Healthy older and younger adults participated in a multifactorial test of cognitive control. Within participants, the procedure varied as a function of the amount contextual load, episodic load, and response-conflict load present. Results: We found that older adults showed impaired performance relative to younger adults. We also found, however, that the response selection process underlying the response-conflict manipulation was a major moderator of age-related differences in both the contextual and episodic load conditions—suggesting a hierarchical organization. Discussion: These findings are consistent with previous findings, suggesting that deficits in cognitive control in older adults are directly related to the resolution of response-conflict and that other apparent deficits may be derivative upon the more basic response-conflict related deficit. PMID:26224757

Contribution of Resting Conductance, GABAA-Receptor Mediated Miniature Synaptic Currents and Neurosteroid to Chloride Homeostasis in Central Neurons.

PubMed

Yelhekar, Tushar D; Druzin, Michael; Johansson, Staffan

2017-01-01

Maintenance of a low intraneuronal Cl - concentration, [Cl - ] i , is critical for inhibition in the CNS. Here, the contribution of passive, conductive Cl - flux to recovery of [Cl - ] i after a high load was analyzed in mature central neurons from rat. A novel method for quantifying the resting Cl - conductance, important for [Cl - ] i recovery, was developed and the possible contribution of GABA A and glycine receptors and of ClC-2 channels to this conductance was analyzed. The hypothesis that spontaneous, action potential-independent release of GABA is important for [Cl - ] i recovery was tested. [Cl - ] i was examined by gramicidin-perforated patch recordings in medial preoptic neurons. Cells were loaded with Cl - by combining GABA or glycine application with a depolarized voltage, and the time course of [Cl - ] i was followed by measurements of the Cl - equilibrium potential , as obtained from the current recorded during voltage ramps combined with GABA or glycine application. The results show that passive Cl - flux contributes significantly, in the same order of magnitude as does K + -Cl - cotransporter 2 (KCC2), to [Cl - ] i recovery and that Cl - conductance accounts for ∼ 6% of the total resting conductance. A major fraction of this resting Cl - conductance is picrotoxin (PTX)-sensitive and likely due to open GABA A receptors, but ClC-2 channels do not contribute. The results also show that when the decay of GABA A receptor-mediated miniature postsynaptic currents (minis) is slowed by the neurosteroid allopregnanolone, such minis may significantly quicken [Cl - ] i recovery, suggesting a possible steroid-regulated role for minis in the control of Cl - homeostasis.

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…

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…

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

Measuring Physician Cognitive Load: Validity Evidence for a Physiologic and a Psychometric Tool

ERIC Educational Resources Information Center

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

2017-01-01

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…

CLASS Challenging Tasks: Using Cognitive Load Theory to Inform the Design of Challenging Mathematical Tasks

ERIC Educational Resources Information Center

Russo, James; Hopkins, Sarah

2017-01-01

This paper outlines a seven-step process for developing problem-solving tasks informed by cognitive load theory. Through an example of a task developed for Year 2 students, we show how this approach can be used to produce challenging mathematical tasks that aim to optimise cognitive load for each student.

Disengagement from tasks as a function of cognitive load and depressive symptom severity.

PubMed

Bowie, Christopher R; Milanovic, Melissa; Tran, Tanya; Cassidy, Sarah

2017-01-01

Depression is associated with impairment in cognition and everyday functioning. Mechanisms of cognitive dysfunction in depression and the factors that influence strategic deployment of cognitive abilities in complex environments remain elusive. In this study we investigated whether depression symptom severity is associated with disengagement from a working memory task (Paced Auditory Serial Addition Task; PASAT) with parametric adjustment of task difficulty. 235 participants completed the Beck Depression Inventory, low and high cognitive load conditions of the PASAT, and quality of life. Cognitive disengagement was the sum of consecutive items in which participants did not proffer a response to the trial. Individuals with higher depression severity showed more cognitive disengagement on the high but not low cognitive load trial of the PASAT; they did not differ in number of correct responses. Increased disengagement from the low to high cognitive load was associated with more impaired quality of life. Depression severity is associated with increased disengagement from tasks as difficulty increases. These findings suggest the importance of measuring how cognitive skills are avoided in complex environments in addition to considering performance accuracy. Individuals with depressive symptoms might preferentially avoid cognitive tasks that are perceived as more complex in spite of intact ability.

Core networks and their reconfiguration patterns across cognitive loads.

PubMed

Zuo, Nianming; Yang, Zhengyi; Liu, Yong; Li, Jin; Jiang, Tianzi

2018-04-20

Different cognitively demanding tasks recruit globally distributed but functionally specific networks. However, the configuration of core networks and their reconfiguration patterns across cognitive loads remain unclear, as does whether these patterns are indicators for the performance of cognitive tasks. In this study, we analyzed functional magnetic resonance imaging data of a large cohort of 448 subjects, acquired with the brain at resting state and executing N-back working memory (WM) tasks. We discriminated core networks by functional interaction strength and connection flexibility. Results demonstrated that the frontoparietal network (FPN) and default mode network (DMN) were core networks, but each exhibited different patterns across cognitive loads. The FPN and DMN both showed strengthened internal connections at the low demand state (0-back) compared with the resting state (control level); whereas, from the low (0-back) to high demand state (2-back), some connections to the FPN weakened and were rewired to the DMN (whose connections all remained strong). Of note, more intensive reconfiguration of both the whole brain and core networks (but no other networks) across load levels indicated relatively poor cognitive performance. Collectively these findings indicate that the FPN and DMN have distinct roles and reconfiguration patterns across cognitively demanding loads. This study advances our understanding of the core networks and their reconfiguration patterns across cognitive loads and provides a new feature to evaluate and predict cognitive capability (e.g., WM performance) based on brain networks. © 2018 Wiley Periodicals, Inc.

Food bundling as a health nudge: Investigating consumer fruit and vegetable selection using behavioral economics.

PubMed

Carroll, Kathryn A; Samek, Anya; Zepeda, Lydia

2018-02-01

Displaying bundles of healthy foods at the grocery store is a health nudge that simplifies shopping and may have the potential for increasing fruit and vegetable (F&V) purchasing. To evaluate the impact of food bundling, we conduct an artefactual field experiment with community participants in a laboratory set up as a grocery store. Dual-self theory suggests that food choices may differ depending on whether shoppers are under cognitive load - in our experiment, we exogenously vary whether bundles are displayed (with and without a price discount) and whether shoppers are under cognitive load. Our findings align with prior studies that suggest unhealthy options are more likely to be selected when cognitive resources are constrained. When bundles are displayed, we observe increased F&V purchasing. We also observe a significant interaction between cognitive load and price discounting. We find discounted bundles are more effective in the absence of cognitive load, but non-discounted bundles are more effective when shoppers are under cognitive load. Although more research is warranted, our findings suggest that when shopping under cognitive load, it is possible that discounts impose additional cognitive strain on the shopping experience. For retailers and policymakers, our results point to the potential power of bundling as a strategy for increasing healthy food purchasing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acoustic Measures of Voice and Physiologic Measures of Autonomic Arousal during Speech as a Function of Cognitive Load.

PubMed

MacPherson, Megan K; Abur, Defne; Stepp, Cara E

2017-07-01

This study aimed to determine the relationship among cognitive load condition and measures of autonomic arousal and voice production in healthy adults. A prospective study design was conducted. Sixteen healthy young adults (eight men, eight women) produced a sentence containing an embedded Stroop task in each of two cognitive load conditions: congruent and incongruent. In both conditions, participants said the font color of the color words instead of the word text. In the incongruent condition, font color differed from the word text, creating an increase in cognitive load relative to the congruent condition in which font color and word text matched. Three physiologic measures of autonomic arousal (pulse volume amplitude, pulse period, and skin conductance response amplitude) and four acoustic measures of voice (sound pressure level, fundamental frequency, cepstral peak prominence, and low-to-high spectral energy ratio) were analyzed for eight sentence productions in each cognitive load condition per participant. A logistic regression model was constructed to predict the cognitive load condition (congruent or incongruent) using subject as a categorical predictor and the three autonomic measures and four acoustic measures as continuous predictors. It revealed that skin conductance response amplitude, cepstral peak prominence, and low-to-high spectral energy ratio were significantly associated with cognitive load condition. During speech produced under increased cognitive load, healthy young adults show changes in physiologic markers of heightened autonomic arousal and acoustic measures of voice quality. Future work is necessary to examine these measures in older adults and individuals with voice disorders. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

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. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of Working Memory Load on Cognitive Control in Trait Anxiety: An ERP Study

PubMed Central

Qi, Senqing; Zeng, Qinghong; Luo, Yangmei; Duan, Haijun; Ding, Cody; Hu, Weiping; Li, Hong

2014-01-01

Whether trait anxiety is associated with a general impairment of cognitive control is a matter of debate. This study investigated whether and how experimentally manipulated working memory (WM) load modulates the relation between trait anxiety and cognitive control. This question was investigated using a dual-task design in combination with event-related potentials. Participants were required to remember either one (low WM load) or six letters (high WM load) while performing a flanker task. Our results showed that a high WM load disrupted participants' ability to overcome distractor interference and this effect was exacerbated for the high trait-anxious (HTA) group. This exacerbation was reflected by larger interference effects (i.e., incongruent minus congruent) on reaction times (RTs) and N2 amplitudes for the HTA group than for the low trait-anxious group under high WM load. The two groups, however, did not differ in their ability to inhibit task-irrelevant distractors under low WM load, as indicated by both RTs and N2 amplitudes. These findings underscore the significance of WM-related cognitive demand in contributing to the presence (or absence) of a general cognitive control deficit in trait anxiety. Furthermore, our findings show that when limited WM resources are depleted by high WM load, HTA individuals exhibit less efficient recruitments of cognitive control required for the inhibition of distractors, therefore resulting in a greater degree of response conflict. PMID:25369121

Impact of working memory load on cognitive control in trait anxiety: an ERP study.

PubMed

Qi, Senqing; Zeng, Qinghong; Luo, Yangmei; Duan, Haijun; Ding, Cody; Hu, Weiping; Li, Hong

2014-01-01

Whether trait anxiety is associated with a general impairment of cognitive control is a matter of debate. This study investigated whether and how experimentally manipulated working memory (WM) load modulates the relation between trait anxiety and cognitive control. This question was investigated using a dual-task design in combination with event-related potentials. Participants were required to remember either one (low WM load) or six letters (high WM load) while performing a flanker task. Our results showed that a high WM load disrupted participants' ability to overcome distractor interference and this effect was exacerbated for the high trait-anxious (HTA) group. This exacerbation was reflected by larger interference effects (i.e., incongruent minus congruent) on reaction times (RTs) and N2 amplitudes for the HTA group than for the low trait-anxious group under high WM load. The two groups, however, did not differ in their ability to inhibit task-irrelevant distractors under low WM load, as indicated by both RTs and N2 amplitudes. These findings underscore the significance of WM-related cognitive demand in contributing to the presence (or absence) of a general cognitive control deficit in trait anxiety. Furthermore, our findings show that when limited WM resources are depleted by high WM load, HTA individuals exhibit less efficient recruitments of cognitive control required for the inhibition of distractors, therefore resulting in a greater degree of response conflict.

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.

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

PubMed

Hiraoka, Daiki; Nomura, Michio

2016-06-16

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.

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

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 afternoon (i.e. high alertness). Taken together, these findings indicate that mental overload can be the result of a combination of subject-related characteristics, including alertness and cognitive appraisal, in addition to well-documented task-related components (intrinsic and extraneous load). As the factors investigated in the study are known to be critically involved in a number of real job-activities, the findings suggest that solutions designed to reduce incidents and accidents at work should consider the situation from a global perspective, including individual characteristics, task parameters, and work organization, rather than dealing with each factor separately.

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…

A Dual Coding Model of Processing Chinese as a Second Language: A Cognitive-Load Approach

ERIC Educational Resources Information Center

Sham, Diana Po Lan

2002-01-01

The research was conducted in Sydney and Hong Kong using students, from grades 5 to 9, whose first language or teaching medium was English, learning to read Chinese as second language. According to cognitive load theory, the processing of single Chinese characters accompanied by pictures should impose extraneous cognitive load and thus hinders…

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…

What is the relationship between mental workload factors and cognitive load types?

PubMed

Galy, Edith; Cariou, Magali; Mélan, Claudine

2012-03-01

The present study tested the hypothesis of an additive interaction between intrinsic, extraneous and germane cognitive load, by manipulating factors of mental workload assumed to have a specific effect on either type of cognitive load. The study of cognitive load factors and their interaction is essential if we are to improve workers' wellbeing and safety at work. High cognitive load requires the individual to allocate extra resources to entering information. It is thought that this demand for extra resources may reduce processing efficiency and performance. The present study tested the effects of three factors thought to act on either cognitive load type, i.e. task difficulty, time pressure and alertness in a working memory task. Results revealed additive effects of task difficulty and time pressure, and a modulation by alertness on behavioral, subjective and psychophysiological workload measures. Mental overload can be the result of a combination of task-related components, but its occurrence may also depend on subject-related characteristics, including alertness. Solutions designed to reduce incidents and accidents at work should consider work organization in addition to task constraints in so far that both these factors may interfere with mental workload. Copyright © 2011 Elsevier B.V. All rights reserved.

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.

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 (c) 2016 APA, all rights reserved).

Acute physical exercise affected processing efficiency in an auditory attention task more than processing effectiveness.

PubMed

Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan

2014-02-01

Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus.

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

NASA Astrophysics Data System (ADS)

Scharfenberg, Franz-Josef; Bogner, Franz X.

2010-04-01

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 followed the newly developed two-step approach derived from cognitive load theory while a control group applied experimentation in a conventional one-step mode. The difference consisted of additional focused discussions combined with noting students' ideas (Step 1) prior to starting any experimental procedure (Step 2). We monitored mental effort (nine times during the teaching unit) and cognitive achievement (in a pre-post-design with follow-up test). The treatment demonstrated a change in instructional efficiency (by combining mental effort and cognitive achievement data), especially for intrinsically high-loaded students. Conclusions for optimizing individual cognitive load in science teaching were drawn.

Patterns of interactions at grade 5 classroom in learning the topic of statistics viewed from cognitive load theory

NASA Astrophysics Data System (ADS)

Setianingsih, R.

2018-01-01

The nature of interactions that occurs among teacher, students, learning sources, and learning environment creates different settings to enhance learning. Any setting created by a teacher is affected by 3 (three) types of cognitive load: intrinsic cognitive load, extraneous cognitive load, and germane cognitive load. This study is qualitative in nature, aims to analyse the patterns of interaction that are constituted in mathematics instructions by taking into account the cognitive load theory. The subjects of this study are 21 fifth-grade students who learn mathematics in small groups and whole-class interactive lessons. The data were collected through classroom observations which were videotaped, while field notes were also taken. The data analysis revealed that students engaged in productive interaction and inquiry while they were learning mathematics in small groups or in whole class setting, in which there was a different type of cognitive load that dominantly affecting the learning processes at each setting. During learning mathematics in whole class setting, the most frequently found interaction patterns were to discuss and compare solution based on self-developed models, followed by expressing opinions. This is consistent with the principles of mathematics learning, which gives students wide opportunities to construct mathematical knowledge through individual learning, learning in small groups as well as learning in whole class settings. It means that by participating in interactive learning, the students are habitually engaged in productive interactions and high level of mathematical thinking.

Signal pathway of hippocampal apoptosis and cognitive impairment of mice caused by cerium chloride.

PubMed

Cheng, Zhe; Li, Na; Cheng, Jie; Hu, Renping; Gao, Guodong; Cui, Yaling; Gong, Xiaolan; Wang, Ling; Hong, Fashui

2012-12-01

Experimental studies have demonstrated that lanthanides could impair cognitive functions of children and animals, but very little is known about the hippocampal apoptosis and its molecular mechanism. The study investigated the signal pathway of hippocampal apoptosis induced by intragastric administration of CeCl(3) for 60 consecutive days. It showed that cerium had been significantly accumulated in the mouse hippocampus, and CeCl(3) caused hippocampal apoptosis and impairment of spatial recognition memory of mice. CeCl(3) effectively activated caspase-3 and -9, inhibited Bcl-2, and increased the levels of Bax and cytochrome c, promoted accumulation of reactive oxygen species in the mouse hippocampus. It implied that CeCl(3)-induced apoptosis in the mouse hippocampus could be triggered via mitochondrion-mediated pathway. Our findings suggest the need for great caution to handle the lanthanides for workers and consumers. 2011 Wiley Periodicals, Inc

The busy social brain: evidence for automaticity and control in the neural systems supporting social cognition and action understanding.

PubMed

Spunt, Robert P; Lieberman, Matthew D

2013-01-01

Much social-cognitive processing is believed to occur automatically; however, the relative automaticity of the brain systems underlying social cognition remains largely undetermined. We used functional MRI to test for automaticity in the functioning of two brain systems that research has indicated are important for understanding other people's behavior: the mirror neuron system and the mentalizing system. Participants remembered either easy phone numbers (low cognitive load) or difficult phone numbers (high cognitive load) while observing actions after adopting one of four comprehension goals. For all four goals, mirror neuron system activation showed relatively little evidence of modulation by load; in contrast, the association of mentalizing system activation with the goal of inferring the actor's mental state was extinguished by increased cognitive load. These results support a dual-process model of the brain systems underlying action understanding and social cognition; the mirror neuron system supports automatic behavior identification, and the mentalizing system supports controlled social causal attribution.

Regulation of intracellular pH in the rabbit cortical collecting tubule.

PubMed Central

Weiner, I D; Hamm, L L

1990-01-01

The cortical collecting tubule (CCT) is an important nephron segment for Na+, K+, water and acid-base transport. Differential loading characteristics of the pH sensitive dye 2',7'-bis-(2-carboxyethyl)-5(and-6)carboxyfluorescein (BCECF) and basolateral Cl- removal were used to identify and study intracellular pH (pHi) regulation in each of three cell types involved in this transport. Both principal cells and beta-intercalated cells were found to have a basolateral Na+/H+ exchanger based on the Na+ and amiloride sensitivity of pHi recovery from acid loads. Intercalated cells demonstrated abrupt pHi changes with basolateral Cl- removal. alpha-intercalated cells alkalinized; beta-intercalated cells acidified. In the beta-intercalated cells, luminal Cl- removal blocked changes in pHi in response to changes in luminal HCO3- or peritubular Cl-, providing direct evidence for a luminal Cl-/HCO3- exchanger. In principal cells, brief removal of either peritubular or luminal Cl- resulted in no change in pHi; however, return of peritubular Cl- after prolonged removal resulted in a rapid fall in pHi consistent with a basolateral Cl-/HCO3- exchanger, which may be relatively inactive under baseline conditions. Therefore, Cl-/HCO3- exchange is present in all three cell types but varies in location and activity. PMID:2153152

Measuring Cognitive Load in Embodied Learning Settings

PubMed Central

Skulmowski, Alexander; Rey, Günter Daniel

2017-01-01

In recent years, research on embodied cognition has inspired a number of studies on multimedia learning and instructional psychology. However, in contrast to traditional research on education and multimedia learning, studies on embodied learning (i.e., focusing on bodily action and perception in the context of education) in some cases pose new problems for the measurement of cognitive load. This review provides an overview over recent studies on embodied learning in which cognitive load was measured using surveys, behavioral data, or physiological measures. The different methods are assessed in terms of their success in finding differences of cognitive load in embodied learning scenarios. At the same time, we highlight the most important challenges for researchers aiming to include these measures into their study designs. The main issues we identified are: (1) Subjective measures must be appropriately phrased to be useful for embodied learning; (2) recent findings indicate potentials as well as problematic aspects of dual-task measures; (3) the use of physiological measures offers great potential, but may require mobile equipment in the context of embodied scenarios; (4) meta-cognitive measures can be useful extensions of cognitive load measurement for embodied learning. PMID:28824473

Asymmetric Spatial Processing Under Cognitive Load.

PubMed

Naert, Lien; Bonato, Mario; Fias, Wim

2018-01-01

Spatial attention allows us to selectively process information within a certain location in space. Despite the vast literature on spatial attention, the effect of cognitive load on spatial processing is still not fully understood. In this study we added cognitive load to a spatial processing task, so as to see whether it would differentially impact upon the processing of visual information in the left versus the right hemispace. The main paradigm consisted of a detection task that was performed during the maintenance interval of a verbal working memory task. We found that increasing cognitive working memory load had a more negative impact on detecting targets presented on the left side compared to those on the right side. The strength of the load effect correlated with the strength of the interaction on an individual level. The implications of an asymmetric attentional bias with a relative disadvantage for the left (vs the right) hemispace under high verbal working memory (WM) load are discussed.

Chloride concentrations, loads, and yields in four watersheds along Interstate 95, southeastern Connecticut, 2008-11: factors that affect peak chloride concentrations during winter storms

USGS Publications Warehouse

Brown, Craig J.; Mullaney, John R.; Morrison, Jonathan; Martin, Joseph W.; Trombley, Thomas J.

2015-07-01

The addition of a lane mile in both directions on I–95 would result in an estimate of approximately 2 to 11 percent increase in Cl- input from deicers applied to I–95 and other roads maintained by Connecticut Department of Transportation. The largest estimated increase in Cl- load was in the watersheds with the greatest number miles of I–95 corridor relative to the total lane miles maintained by Connecticut Department of Transportation. On the basis of these estimates and the estimated peak Cl- concentrations during the study period, it is unlikely that the increased use of deicers on the additional lanes would lead to Cl- concentrations that exceed the aquatic habitat criteria.

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…

Instruction-First and Problem-Solving-First Approaches: Alternative Pathways to Learning Complex Tasks

ERIC Educational Resources Information Center

Likourezos, Vicki; Kalyuga, Slava

2017-01-01

According to cognitive load theory, using worked examples is an effective and efficient instructional strategy for initial cognitive skill acquisition for novice learners, as it reduces cognitive load and frees up cognitive resources to build task competence. Contrary to this, productive failure (as well as invention learning, desirable…

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…

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. PsycINFO Database Record (c) 2013 APA, all rights reserved

Cl sup minus -HCO sub 3 sup minus exchange is present with Na sup + -K sup + -Cl sup minus cotransport in rabbit parotid acinar basolateral membranes

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

Turner, R.J.; George, J.N.

1988-03-01

The presence of a sodium-independent electroneutral Cl{sup {minus}}-anion exchanger in a basolateral membrane vesicle preparation from the rabbit parotid is demonstrated. This exchanger is shared by HCO{sub 3}{sup {minus}}, NO{sub 3}{sup {minus}}, Br{sup {minus}}, F{sup {minus}}, and formate, but not by thiocyanate, acetate, methylsulfate, gluconate, or hydroxyl ions. In order of relative potency, the exchanger is inhibited by SITS {ge} phloretin > furosemide > bumetanide {ge} phlorizin. A Na{sup +}-K{sup +}-dependent component of chloride flux, presumably due to the Na{sup +}-K{sup +}-Cl{sup {minus}} cotransporter already characterized in this preparation, was also observed. {sup 36}Cl uptake into vesicles loaded with KClmore » exhibited an overshoot of intravesicular ({sup 36}Cl) due to {sup 36}Cl-Cl exchange. However, when vesicles were loaded with both KCl and NaCl the height of the overshoot was considerably decreased indicating a Na{sup +}-K{sup +}-dependent dissipation of the intravesicular to extravesicular chloride gradient. This experiment provides strong evidence that the Na{sup +}-K{sup +}Cl{sup {minus}} cotransporter and the Cl{sup {minus}} HCO{sub 3}{sup {minus}} exchange are present in the same membrane vesicles. These results indicate that Cl{sup {minus}}-HCO{sub 3}{sup {minus}} exchange is present in the basolateral membrane of parotid acinar cells and thus that this transporter may play a significant role in salivary secretion.« less

Effects of Cognitive Load on Trust

DTIC Science & Technology

2011-11-01

individualistic culture ; (2) examining the relationship between cognitive load and trust. 15. SUBJECT TERMS Cognitive Psychology , Behavioural...This report covers results of two research tasks: (1) evaluating the relative strength of Mayer?s trustworthiness indicators in both a collectivistic and

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…

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…

Synthesis and Characterization of Protein-Conjugated Silver Nanoparticles/Silver Salt Loaded Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) Film for Prevention of Bacterial Infections and Potential Use in Bone Tissue Engineering Applications

NASA Astrophysics Data System (ADS)

Bakare, Rotimi Ayotunde

Failure of orthopedic implants due to bacterial infection has been a major concern in bone tissue engineering. To this end, we have formulated a potential orthopedic implant made of naturally occurring biodegradable polymer, i.e. poly (3-hydroxylbutyrate-co-3-hydroxylvalerate) (PHBV), modified with BSA conjugated silver nanoparticles and or silver chloride. Upon release of Ag NPs and or Ag+ in the implant region, can promote aseptic environment by inhibition of bacteria growth and also support/maintain bone cell adhesion, growth, and proliferation. For formulating nanoparticles loaded PHBV scaffold, we exploit specific interaction between bovine serum albumin (BSA) of BSA capped silver nanoparticles and collagen of collagen immobilized PHBV scaffold. Therefore, the first part of this study dealt with synthesis and characterization of collagen immobilized PHBV film for loading of BSA stabilized silver (Ag/BSA) nanoparticles. Two different approaches were used to immobilize collagen on macroporous PHBV film. First approach uses thermal radical copolymerization with 2-hydroxyethylmethacrylate (HEMA), while the second approach uses aminolysis to functionalize macroporous PHBV film. Using collagen crosslinker, type I collagen was covalently grafted to formulate collagen immobilized PHEMA-g-PHBV and collagen immobilized NH2-PHBV films, respectively. Spectroscopic (FTIR, XPS), physical (SEM), and thermal (TGA) techniques were used to characterize the functionalized PHBV films. The Ag/BSA nanoparticles were then loaded on collagen immobilized PHBV films and untreated PHBV films. The concentration of nanoparticles loaded on PHBV film was determined by atomic absorption spectrometry and fluorescence spectroscopy. The amount of nanoparticles loaded on collagen immobilized PHBV film was found to be significantly greater than that on untreated PHBV film. The amount of Ag/BSA nanoparticles loaded on collagen immobilized PHBV film was found to depend on the concentration of Ag/BSA nanoparticles solution used for loading and on the molecular weight of type I collagen used in collagen immobilization on PHBV film. At physiological pH, optimum amount of nanoparticles was retained on Type I collagen immobilized PHBV film because at pH 7.4, protonated amino groups of collagen immobilized PHBV film promote strong electrostatic interaction with the carboxylate anions of BSA stabilized silver nanoparticles. The second part of this study dealt with formulating AgCl/PHBV film that can potentially release silver ions for effective antimicrobial activity. In this study, we formulated AgCl/PHBV composite film by a salt exchange mechanism. Thermogravimetric analysis (TGA) was used to quantify the amount of NaCl present before and after salt exchange. The Na content in the pre-washed and partially washed NaCl/PHBV film was found to be 43.60% and 1.24% by mass, respectively. The AgCl/PBHV composite film was acid digested and assayed for Na+ and Ag+ content by using Atomic Absorption Spectrometry (AAS) and was found to be 2.15 and 10.25 ppm, respectively. XPS technique was used to characterize the surface elemental composition of the AgCl/PHBV composite film. The survey spectrum of AgCl/PHBV film showed emergence of Ag 3d and Cl 2s peaks compared to pure PHBV which was predominantly composed of C 1s and O 1s peaks. The release kinetics of silver ions from AgCl/PHBV composite film showed an initial burst of about 1.5 ppm of silver ions during the first day of desorption followed by a gradual release of silver ions at an average rate of 0.3 ppm per day during the span of two weeks studied. Ag/BSA nanoparticles loaded collagen immobilized PHBV films and AgCl/PHBV composite films were tested for antibacterial efficacy against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Colony forming unit and optical density measurements of Ag/BSA nanoparticles loaded collagen immobilized PHBV films showed broad antimicrobial activity at low Ag/BSA nanoparticles concentration (0.19and 0.31 microg) compared to commercially available gentamicin and sulfamethoxazole/trimethoprim which showed sometimes selective antimicrobial activity and antimicrobial activity at high concentration (10 microg and 23.75/1.25 microg/disc). Additionally, a clear zone of inhibition around AgCl/PHBV composite film was noticed on a modified Kirby-Bauer disk diffusion assay. Optical density results and colony forming unit measurements showed that AgCl/PHBV composite film exhibit broad bactericidal activity. Next, we evaluated the cytotoxicity of Ag/BSA nanoparticles loaded collagen immobilized PHBV films and AgCl/PHBV composite films towards MC3T3-E1 cells at the same concentration both films showed broad antimicrobial activity. By using MTT assay, we established that Ag/BSA nanoparticles loaded collagen immobilized PHBV film showed minimal, if any, cytotoxic effect towards MC3T3-E1 cells while AgCl/PHBV composite film showed significant cytotoxic effect compared to tissue culture polystyrene. Our research findings provide several formulations for preparation of scaffold, if properly tuned; it can be used as a potential biocompatible and biodegradable scaffold for the prevention of bacterial infections and promotion of cell attachment and proliferation in bone tissue engineering applications.

Allostatic load but not medical burden predicts memory performance in late-life bipolar disorder.

PubMed

Vaccarino, Sophie R; Rajji, Tarek K; Gildengers, Ariel G; Waters, Sarah E S; Butters, Meryl A; Menon, Mahesh; Blumberger, Daniel M; Voineskos, Aristotle N; Miranda, Dielle; Mulsant, Benoit H

2018-03-01

Older patients with bipolar disorder (BD) present with variable degrees of cognitive impairment. Over time, stress, mood episodes, and comorbidities increase the body's allostatic load. We assessed the extent to which allostatic load vs more traditional measures of medical burden account for the heterogeneity in cognition in this population. Thirty-five older euthymic patients with BD and 30 age-equated, gender-equated, and education-equated comparison participants were administered a comprehensive assessment including a neuropsychological battery, and 9 physiological measures to determine allostatic load. The relationship among allostatic load, medical burden, and cognition was assessed. Compared with the mentally healthy comparators, patients were impaired globally, and in 4 cognitive domains-information-processing speed / executive functioning, delayed memory, language, and visuomotor ability, and presented with greater medical burden but not a different allostatic load. Allostatic load, but not medical burden, was associated with delayed memory performance both in a correlational analysis and in a multivariate regression analysis. Euthymic older patients with BD are impaired on several cognitive domains and have high medical burden. Their memory performance is more strongly associated with allostatic load than with traditional measures of medical burden. These findings need to be replicated and extended longitudinally. Copyright © 2017 John Wiley & Sons, Ltd.

Collaborative use of virtual patients after a lecture enhances learning with minimal investment of cognitive load.

PubMed

Marei, Hesham F; Donkers, Jeroen; Al-Eraky, Mohamed M; Van Merrienboer, Jeroen J G

2018-05-25

The use of virtual patients (VPs), due to their high complexity and/or inappropriate sequencing with other instructional methods, might cause a high cognitive load, which hampers learning. To investigate the efficiency of instructional methods that involved three different applications of VPs combined with lectures. From two consecutive batches, 171 out of 183 students have participated in lecture and VPs sessions. One group received a lecture session followed by a collaborative VPs learning activity (collaborative deductive). The other two groups received a lecture session and an independent VP learning activity, which either followed the lecture session (independent deductive) or preceded it (independent inductive). All groups were administrated written knowledge acquisition and retention tests as well as transfer tests using two new VPs. All participants completed a cognitive load questionnaire, which measured intrinsic, extraneous and germane load. Mixed effect analysis of cognitive load and efficiency using the R statistical program was performed. The highest intrinsic and extraneous load was found in the independent inductive group, while the lowest intrinsic and extraneous load was seen in the collaborative deductive group. Furthermore, comparisons showed a significantly higher efficiency, that is, higher performance in combination with lower cognitive load, for the collaborative deductive group than for the other two groups. Collaborative use of VPs after a lecture is the most efficient instructional method, of those tested, as it leads to better learning and transfer combined with lower cognitive load, when compared with independent use of VPs, either before or after the lecture.

Alpha-lipoic acid-mediated activation of muscarinic receptors improves hippocampus- and amygdala-dependent memory.

PubMed

Mahboob, Aamra; Farhat, Syeda Mehpara; Iqbal, Ghazala; Babar, Mustafeez Mujtaba; Zaidi, Najam-us-Sahar Sadaf; Nabavi, Seyed Mohammad; Ahmed, Touqeer

2016-04-01

Aluminum (Al) is a neurotoxic agent which readily crosses the blood-brain-barrier (BBB) and accumulates in the brain leading to neurodegenerative disorders, characterised by cognitive impairment. Alpha-lipoic acid (ALA) is an antioxidant and has a potential to improve cognitive functions. This study aimed to evaluate the neuroprotective effect of ALA in AlCl3-induced neurotoxicity mouse model. Effect of ALA (25mg/kg/day) was evaluated in the AlCl3-induced neurotoxicity (AlCl3 150 mg/kg/day) mouse model on learning and memory using behaviour tests and on the expression of muscarinic receptor genes (using RT-PCR), in hippocampus and amygdala. Following ALA treatment, the expression of muscarinic receptor genes M1, M2 and choline acetyltransferase (ChaT) were significantly improved (p<0.05) relative to AlCl3-treated group. ALA enhanced fear memory (p<0.01) and social novelty preference (p<0.001) comparative to the AlCl3-treated group. Fear extinction memory was remarkably restored (p<0.001) in ALA-treated group demonstrated by reduced freezing response as compared to the AlCl3-treated group which showed higher freezing. In-silico analysis showed that racemic mixture of ALA has higher binding affinity for M1 and M2 compared to acetylcholine. These novel findings highlight the potential role of ALA in cognitive functions and cholinergic system enhancement thus presenting it an enviable therapeutic candidate for the treatment of neurodegenerative disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

Learner, Patient, and Supervisor Features Are Associated With Different Types of Cognitive Load During Procedural Skills Training: Implications for Teaching and Instructional Design.

PubMed

Sewell, Justin L; Boscardin, Christy K; Young, John Q; Ten Cate, Olle; O'Sullivan, Patricia S

2017-11-01

Cognitive load theory, focusing on limits of the working memory, is relevant to medical education; however, factors associated with cognitive load during procedural skills training are not well characterized. The authors sought to determine how features of learners, patients/tasks, settings, and supervisors were associated with three types of cognitive load among learners performing a specific procedure, colonoscopy, to identify implications for procedural teaching. Data were collected through an electronically administered survey sent to 1,061 U.S. gastroenterology fellows during the 2014-2015 academic year; 477 (45.0%) participated. Participants completed the survey immediately following a colonoscopy. Using multivariable linear regression analyses, the authors identified sets of features associated with intrinsic, extraneous, and germane loads. Features associated with intrinsic load included learners (prior experience and year in training negatively associated, fatigue positively associated) and patient/tasks (procedural complexity positively associated, better patient tolerance negatively associated). Features associated with extraneous load included learners (fatigue positively associated), setting (queue order positively associated), and supervisors (supervisor engagement and confidence negatively associated). Only one feature, supervisor engagement, was (positively) associated with germane load. These data support practical recommendations for teaching procedural skills through the lens of cognitive load theory. To optimize intrinsic load, level of experience and competence of learners should be balanced with procedural complexity; part-task approaches and scaffolding may be beneficial. To reduce extraneous load, teachers should remain engaged, and factors within the procedural setting that may interfere with learning should be minimized. To optimize germane load, teachers should remain engaged.

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.

The relation of cognitive load and pupillary unrest.

PubMed

Müller, Andreas; Petru, Raluca; Seitz, Lucia; Englmann, Ines; Angerer, Peter

2011-06-01

This study examines the relationship between pupillary unrest (PU) and cognitive load. PU represents a measure of reduced central nervous tonic arousal (sleepiness). A loss of tonic arousal can be associated with difficulties in maintaining the required level of performance. Thus, the measurement of tonic arousal in occupational contexts can help to prevent overload or errors. We compared a group with high cognitive load (30 apron controllers of an international airport) with a control group with low cognitive load (63 healthy people during their free time) in a non-randomized experimental design with pre- and post-test assessment of PU. PU was scanned by an infrared sensor with a frequency of 25 Hz and a resolution of .05 mm. To control for circadian effects, measurements for both groups were taken at the same time of the day. High PU at the start of the shift correlated with high perceived load during the shift. There were no indications of reverse effects. Analyses of group x time effects with generalized linear models (repeated measures) revealed that cognitive load did in no way affected PU. Initially low tonic arousal (indicated by high PU) may predict subsequent workload, but being exposed to high cognitive load does not influence tonic arousal after the end of the shift. With that, the study contributes to valid interpretations of pupillary unrest measurements in occupational contexts.

Increasing Cognitive Load Reduces Interference from Masked Appetitive and Aversive but Not Neutral Stimuli

PubMed Central

Uher, Rudolf; Brooks, Samantha J.; Bartholdy, Savani; Tchanturia, Kate; Campbell, Iain C.

2014-01-01

Interactions between cognition and emotion are important for survival, often occurring in the absence of awareness. These interactions have been proposed to involve competition between cognition and emotion for attentional resources. Emotional stimuli have been reported to impair performance on cognitive tasks of low, but not high, load if stimuli are consciously perceived. This study explored whether this load-dependent interference effect occurred in response to subliminal emotional stimuli. Masked emotional (appetitive and aversive), but not neutral, stimuli interfered with performance accuracy but not response time on a cognitive task (n-back) at low (1-back), but not high (2-back) load. These results show that a load-dependent interference effect applies to masked emotional stimuli and that the effect generalises across stimulus categories with high motivational value. This supports models of selective attention that propose that cognition and emotion compete for attentional resources. More specifically, interference from masked emotional stimuli at low load suggests that attention is biased towards salient stimuli, while dissipation of interference under high load involves top-down regulation of attention. Our data also indicate that top-down goal-directed regulation of attention occurs in the absence of awareness and does not require metacognitive monitoring or evaluation of bias over behaviour, i.e., some degree of self-regulation occurs at a non-conscious level. PMID:24709953

Systematic review of measurement tools to assess surgeons' intraoperative cognitive workload.

PubMed

Dias, R D; Ngo-Howard, M C; Boskovski, M T; Zenati, M A; Yule, S J

2018-04-01

Surgeons in the operating theatre deal constantly with high-demand tasks that require simultaneous processing of a large amount of information. In certain situations, high cognitive load occurs, which may impact negatively on a surgeon's performance. This systematic review aims to provide a comprehensive understanding of the different methods used to assess surgeons' cognitive load, and a critique of the reliability and validity of current assessment metrics. A search strategy encompassing MEDLINE, Embase, Web of Science, PsycINFO, ACM Digital Library, IEEE Xplore, PROSPERO and the Cochrane database was developed to identify peer-reviewed articles published from inception to November 2016. Quality was assessed by using the Medical Education Research Study Quality Instrument (MERSQI). A summary table was created to describe study design, setting, specialty, participants, cognitive load measures and MERSQI score. Of 391 articles retrieved, 84 met the inclusion criteria, totalling 2053 unique participants. Most studies were carried out in a simulated setting (59 studies, 70 per cent). Sixty studies (71 per cent) used self-reporting methods, of which the NASA Task Load Index (NASA-TLX) was the most commonly applied tool (44 studies, 52 per cent). Heart rate variability analysis was the most used real-time method (11 studies, 13 per cent). Self-report instruments are valuable when the aim is to assess the overall cognitive load in different surgical procedures and assess learning curves within competence-based surgical education. When the aim is to assess cognitive load related to specific operative stages, real-time tools should be used, as they allow capture of cognitive load fluctuation. A combination of both subjective and objective methods might provide optimal measurement of surgeons' cognition. © 2018 BJS Society Ltd Published by John Wiley & Sons Ltd.

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.

Critical load: a novel approach to determining a sustainable intensity during resistance exercise.

PubMed

Arakelian, Vivian M; Mendes, Renata G; Trimer, Renata; Rossi Caruso, Flavia C; de Sousa, Nuno M; Borges, Vanessa C; do Valle Gomes Gatto, Camila; Baldissera, Vilmar; Arena, Ross; Borghi-Silva, Audrey

2017-05-01

A hyperbolic function as well as a linear relationship between power output and time to exhaustion (Tlim) has been consistently observed during dynamic non-resistive exercises. However, little is known about its concept to resistance exercises (RE), which could be defined as critical load (CL). This study aimed to verify the existence of CL during dynamic RE and to verify the number of workbouts necessary to determine the optimal modeling to achieve it. Fifteen healthy men (23±2.5 yrs) completed 1 repetition maximum test (1RM) on a leg press and 3 (60%, 75% and 90% of 1RM) or 4 (+ 30% of 1RM) workbouts protocols to obtain the CL by hyperbolic and linear regression models between Tlim and load performed. Blood lactate and leg fatigue were also measured. CL was obtained during RE and 3 workbouts protocol estimate it at 53% while 4 tests at 38% of 1 RM. However, based on coefficients of determination, 3 protocols provided a better fit than the 4-parameter model, respectively (R2>0.95 vs. >0.77). Moreover, all intensities increased blood lactate and leg fatigue, however, when corrected by Tlim, were significantly lower at CL. It was possible to determinate CL during dynamic lower limbs RE and that 3 exhaustive workbouts can be used to better estimate the CL, constituting a new concept of determining this threshold during dynamic RE and reducing the physically demanding nature of the protocol. These findings may have important applications for functional performance evaluation and prescription of RE programs.

Prefrontal inhibition of threat processing reduces working memory interference

PubMed Central

Clarke, Robert; Johnstone, Tom

2013-01-01

Bottom-up processes can interrupt ongoing cognitive processing in order to adaptively respond to emotional stimuli of high potential significance, such as those that threaten wellbeing. However it is vital that this interference can be modulated in certain contexts to focus on current tasks. Deficits in the ability to maintain the appropriate balance between cognitive and emotional demands can severely impact on day-to-day activities. This fMRI study examined this interaction between threat processing and cognition; 18 adult participants performed a visuospatial working memory (WM) task with two load conditions, in the presence and absence of anxiety induction by threat of electric shock. Threat of shock interfered with performance in the low cognitive load condition; however interference was eradicated under high load, consistent with engagement of emotion regulation mechanisms. Under low load the amygdala showed significant activation to threat of shock that was modulated by high cognitive load. A directed top-down control contrast identified two regions associated with top-down control; ventrolateral PFC and dorsal ACC. Dynamic causal modeling provided further evidence that under high cognitive load, top-down inhibition is exerted on the amygdala and its outputs to prefrontal regions. Additionally, we hypothesized that individual differences in a separate, non-emotional top-down control task would predict the recruitment of dorsal ACC and ventrolateral PFC during top-down control of threat. Consistent with this, performance on a separate dichotic listening task predicted dorsal ACC and ventrolateral PFC activation during high WM load under threat of shock, though activation in these regions did not directly correlate with WM performance. Together, the findings suggest that under high cognitive load and threat, top-down control is exerted by dACC and vlPFC to inhibit threat processing, thus enabling WM performance without threat-related interference. PMID:23750133

Cognitive Training and Initial Use of Referential Speech.

ERIC Educational Resources Information Center

Kahn, James V.

1984-01-01

Profoundly retarded 3-10 year olds (N=24) were divided into three groups: two cognitive training programs--object permanence or means-end--and language only. Results of pre- and posttests revealed that the cognitive training approaches were successful in enabling the majority of Ss to learn to use speech. (CL)

Using EEG to Discriminate Cognitive Workload and Performance Based on Neural Activation and Connectivity

DTIC Science & Technology

2016-05-31

auditory working memory task to vary cognitive workload by altering the number of digits held in memory during the simultaneous retention of a sentence...in memory . Cognitive efficacy is assessed based on accuracy in recalling digits from memory . A Gaussian classifier is used to discriminate cognitive...effectiveness of cognition under the existing load. One major factor that impacts cognitive load is the amount of working memory required in a task

Does task-irrelevant colour information create extraneous cognitive load? Evidence from a learning task.

PubMed

Miller, Paul; Hazan-Liran, Batel; Cohen, Danielle

2018-06-01

Previous studies have shown that task-irrelevant information impedes learning by creating extraneous cognitive load. But still open is whether such intrusion reflects a purely semantic phenomenon or whether it also stands for sheer perceptual interference. Using Cognitive Load Theory as a framework, this study aimed to answer this question by examining whether and how task-irrelevant colour information modifies extraneous cognitive load in relation to a new code-learning paradigm. For this purpose, university students were asked to learn, based on an example, associations between colour-related and colour-unrelated words and digits presented in black or in a mismatched ink colour. Evident costs in learning efficacy were found in learning the associations between words and digits for colour-related, but not for colour-unrelated, word stimuli. This suggests that interference by task-irrelevant information in learning stands for a mere semantic conflict. Implications of the findings for extraneous cognitive load on learning efficacy are discussed.

Suppression, accessibility of death-related thoughts, and cultural worldview defense: exploring the psychodynamics of terror management.

PubMed

Arndt, J; Greenberg, J; Solomon, S; Pyszczynski, T; Simon, L

1997-07-01

Previous research has shown that after a mortality-salience (MS) treatment, death thought accessibility and worldview defense are initially low and then increase after a delay, suggesting that a person's initial response to conscious thoughts of mortality is to actively suppress death thoughts. If so, then high cognitive load, by disrupting suppression efforts, should lead to immediate increases in death thought accessibility and cultural worldview defense. Studies 1 and 2 supported this reasoning. Specifically, Study 1 replicated the delayed increase in death accessibility after MS among low cognitive load participants but showed a reversed pattern among participants under high cognitive load. Study 2 showed that, unlike low cognitive load participants, high cognitive load participants exhibited immediate increase in pro-American bias after MS. Study 3 demonstrated that worldview defense in response to MS reduces the delayed increase in death accessibility. Implications of these findings for understanding both terror management processes and psychological defense in general are discussed.

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.

Auditory working memory load impairs visual ventral stream processing: toward a unified model of attentional load.

PubMed

Klemen, Jane; Büchel, Christian; Bühler, Mira; Menz, Mareike M; Rose, Michael

2010-03-01

Attentional interference between tasks performed in parallel is known to have strong and often undesired effects. As yet, however, the mechanisms by which interference operates remain elusive. A better knowledge of these processes may facilitate our understanding of the effects of attention on human performance and the debilitating consequences that disruptions to attention can have. According to the load theory of cognitive control, processing of task-irrelevant stimuli is increased by attending in parallel to a relevant task with high cognitive demands. This is due to the relevant task engaging cognitive control resources that are, hence, unavailable to inhibit the processing of task-irrelevant stimuli. However, it has also been demonstrated that a variety of types of load (perceptual and emotional) can result in a reduction of the processing of task-irrelevant stimuli, suggesting a uniform effect of increased load irrespective of the type of load. In the present study, we concurrently presented a relevant auditory matching task [n-back working memory (WM)] of low or high cognitive load (1-back or 2-back WM) and task-irrelevant images at one of three object visibility levels (0%, 50%, or 100%). fMRI activation during the processing of the task-irrelevant visual stimuli was measured in the lateral occipital cortex and found to be reduced under high, compared to low, WM load. In combination with previous findings, this result is suggestive of a more generalized load theory, whereby cognitive load, as well as other types of load (e.g., perceptual), can result in a reduction of the processing of task-irrelevant stimuli, in line with a uniform effect of increased load irrespective of the type of load.

Cognitive Spare Capacity as an Index of Listening Effort.

PubMed

Rudner, Mary

2016-01-01

Everyday listening may be experienced as effortful, especially by individuals with hearing loss. This may be due to internal factors, such as cognitive load, and external factors, such as noise. Even when speech is audible, internal and external factors may combine to reduce cognitive spare capacity, or the ability to engage in cognitive processing of spoken information. A better understanding of cognitive spare capacity and how it can be optimally allocated may guide new approaches to rehabilitation and ultimately improve outcomes. This article presents results of three tests of cognitive spare capacity:1. Sentence-final Word Identification and Recall (SWIR) test2. Cognitive Spare Capacity Test (CSCT)3. Auditory Inference Span Test (AIST)Results show that noise reduces cognitive spare capacity even when speech intelligibility is retained. In addition, SWIR results show that hearing aid signal processing can increase cognitive spare capacity, and CSCT and AIST results show that increasing load reduces cognitive spare capacity. Correlational evidence suggests that while the effect of noise on cognitive spare capacity is related to working memory capacity, the effect of load is related to executive function. Future studies should continue to investigate how hearing aid signal processing can mitigate the effect of load on cognitive spare capacity, and whether such effects can be enhanced by developing executive skills through training. The mechanisms modulating cognitive spare capacity should be investigated by studying their neural correlates, and tests of cognitive spare capacity should be developed for clinical use in conjunction with developing new approaches to rehabilitation.

Effects of Cognitive Load on Trusting Behavior – An Experiment Using the Trust Game

PubMed Central

2015-01-01

Last decades have witnessed a progressing decline of social trust, which has been predominantly linked to worsening economic conditions and increasing social inequality. In the present research we propose a different type of explanation for the observed decline – cognitive load related to technological development and the accelerating pace of modern life. In an experimental study participants played the trust game while performing one of two different secondary tasks – listening to a disturbing noise or memorizing a sequence of characters – or with no additional task in the control condition. Results show that in both cognitive load conditions participants expressed significantly less trust in the trust game than in case of no cognitive load. Additionally, when cognitive resources were limited, participants’ behavior was more impulsive than when their resources were fully available. PMID:26010489

The impact of cognitive load on delayed recall.

PubMed

Camos, Valérie; Portrat, Sophie

2015-08-01

Recent studies have suggested that long-term retention of items studied in a working memory span task depends on the refreshing of memory items-more specifically, on the number of refreshing opportunities. However, it was previously shown that refreshing depends on the cognitive load of the concurrent task introduced in the working memory span task. Thus, cognitive load should determine the long-term retention of items assessed in a delayed-recall test if such retention relies on refreshing. In two experiments, while the amount of refreshing opportunities remained constant, we varied the cognitive load of the concurrent task by either introducing tasks differing in their attentional demands or varying the pace of the concurrent task. To verify that this effect was related to refreshing and not to any maintenance mechanism, we also manipulated the availability of subvocal rehearsal. Replicating previous results, increasing cognitive load reduced immediate recall. This increase also had a detrimental effect on delayed recall. Conversely, the addition of concurrent articulation reduced immediate but not delayed recall. This study shows that both working and episodic memory traces depend on the cognitive load of the concurrent task, whereas the use of rehearsal affects only working memory performance. These findings add further evidence of the dissociation between subvocal rehearsal and attentional refreshing.

Low cortical iron and high entorhinal cortex volume promote cognitive functioning in the oldest-old.

PubMed

van Bergen, Jiri M G; Li, Xu; Quevenco, Frances C; Gietl, Anton F; Treyer, Valerie; Leh, Sandra E; Meyer, Rafael; Buck, Alfred; Kaufmann, Philipp A; Nitsch, Roger M; van Zijl, Peter C M; Hock, Christoph; Unschuld, Paul G

2018-04-01

The aging brain is characterized by an increased presence of neurodegenerative and vascular pathologies. However, there is substantial variation regarding the relationship between an individual's pathological burden and resulting cognitive impairment. To identify correlates of preserved cognitive functioning at highest age, the relationship between β-amyloid plaque load, presence of small vessel cerebrovascular disease (SVCD), iron-burden, and brain atrophy was investigated. Eighty cognitively unimpaired participants (44 oldest-old, aged 85-96 years; 36 younger-old, aged 55-80 years) were scanned by integrated positron emission tomography-magnetic resonance imaging for assessing beta regional amyloid plaque load (18F-flutemetamol), white matter hyperintensities as an indicator of SVCD (fluid-attenuated inversion recovery-magnetic resonance imaging), and iron load (quantitative susceptibility mapping). For the oldest-old group, lower cortical volume, increased β-amyloid plaque load, prevalence of SVCD, and lower cognitive performance in the normal range were found. However, compared to normal-old, cortical iron burden was lower in the oldest-old. Moreover, only in the oldest-old, entorhinal cortex volume positively correlated with β-amyloid plaque load. Our data thus indicate that the co-occurrence of aging-associated neuropathologies with reduced quantitative susceptibility mapping measures of cortical iron load constitutes a lower vulnerability to cognitive loss. Copyright © 2017 Elsevier Inc. All rights reserved.

The effects of tDCS upon sustained visual attention are dependent on cognitive load.

PubMed

Roe, James M; Nesheim, Mathias; Mathiesen, Nina C; Moberget, Torgeir; Alnæs, Dag; Sneve, Markus H

2016-01-08

Transcranial Direct Current Stimulation (tDCS) modulates the excitability of neuronal responses and consequently can affect performance on a variety of cognitive tasks. However, the interaction between cognitive load and the effects of tDCS is currently not well-understood. We recorded the performance accuracy of participants on a bilateral multiple object tracking task while undergoing bilateral stimulation assumed to enhance (anodal) and decrease (cathodal) neuronal excitability. Stimulation was applied to the posterior parietal cortex (PPC), a region inferred to be at the centre of an attentional tracking network that shows load-dependent activation. 34 participants underwent three separate stimulation conditions across three days. Each subject received (1) left cathodal / right anodal PPC tDCS, (2) left anodal / right cathodal PPC tDCS, and (3) sham tDCS. The number of targets-to-be-tracked was also manipulated, giving a low (one target per visual field), medium (two targets per visual field) or high (three targets per visual field) tracking load condition. It was found that tracking performance at high attentional loads was significantly reduced in both stimulation conditions relative to sham, and this was apparent in both visual fields, regardless of the direction of polarity upon the brain's hemispheres. We interpret this as an interaction between cognitive load and tDCS, and suggest that tDCS may degrade attentional performance when cognitive networks become overtaxed and unable to compensate as a result. Systematically varying cognitive load may therefore be a fruitful direction to elucidate the effects of tDCS upon cognitive functions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects of Zoledronate and Mechanical Loading during Simulated Weightlessness on Bone Structure and Mechanical Properties

NASA Technical Reports Server (NTRS)

Scott, R. T.; Nalavadi, M. O.; Shirazi-Fard, Y.; Castillo, A. B.; Alwood, J. S.

2016-01-01

Space flight modulates bone remodeling to favor bone resorption. Current countermeasures include an anti-resorptive drug class, bisphosphonates (BP), and high-force loading regimens. Does the combination of anti-resorptives and high-force exercise during weightlessness have negative effects on the mechanical and structural properties of bone? In this study, we implemented an integrated model to mimic mechanical strain of exercise via cyclical loading (CL) in mice treated with the BP Zoledronate (ZOL) combined with hindlimb unloading (HU). Our working hypothesis is that CL combined with ZOL in the HU model induces additive structural and mechanical changes. Thirty-two C57BL6 mice (male,16 weeks old, n8group) were exposed to 3 weeks of either HU or normal ambulation (NA). Cohorts of mice received one subcutaneous injection of ZOL (45gkg), or saline vehicle, prior to experiment. The right tibia was axially loaded in vivo, 60xday to 9N in compression, repeated 3xweek during HU. During the application of compression, secant stiffness (SEC), a linear estimate of slope of the force displacement curve from rest (0.5N) to max load (9.0N), was calculated for each cycle once per week. Ex vivo CT was conducted on all subjects. For ex vivo mechanical properties, non-CL left femurs underwent 3-point bending. In the proximal tibial metaphysis, HU decreased, CL increased, and ZOL increased the cancellous bone volume to total volume ratio by -26, +21, and +33, respectively. Similar trends held for trabecular thickness and number. Ex vivo left femur mechanical properties revealed HU decreased stiffness (-37),and ZOL mitigated the HU stiffness losses (+78). Data on the ex vivo Ultimate Force followed similar trends. After 3 weeks, HU decreased in vivo SEC (-16). The combination of CL+HU appeared additive in bone structure and mechanical properties. However, when HU + CL + ZOL were combined, ZOL had no additional effect (p0.05) on in vivo SEC. Structural data followed this trend with ZOL not modulating trabecular thickness in CL + NAHU mice. In summary, our integrated model simulates the combination of weightlessness, exercise-induced mechanical strain, and anti-resorptive treatment that astronauts experience during space missions. Based on these results, we conclude that, at the structural and stiffness level, zoledronate treatment during simulated spaceflight does not impede the skeletal response to axial compression. In contrast to our hypothesis, our data show that zoledronate confers no additional mechanical or structural benefit beyond those gained from cyclical loading.

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…

The effects of using screencasting as a multimedia pre-training tool to manage the intrinsic cognitive load of chemical equilibrium instruction for advanced high school chemistry students

NASA Astrophysics Data System (ADS)

Musallam, Ramsey

Chemistry is a complex knowledge domain. Specifically, research notes that Chemical Equilibrium presents greater cognitive challenges than other topics in chemistry. Cognitive Load Theory describes the impact a subject, and the learning environment, have on working memory. Intrinsic load is the facet of Cognitive Load Theory that explains the complexity innate to complex subjects. The purpose of this study was to build on the limited research into intrinsic cognitive load, by examining the effects of using multimedia screencasts as a pre-training technique to manage the intrinsic cognitive load of chemical equilibrium instruction for advanced high school chemistry students. A convenience sample of 62 fourth-year high school students enrolled in an advanced chemistry course from a co-ed high school in urban San Francisco were given a chemical equilibrium concept pre-test. Upon conclusion of the pre-test, students were randomly assigned to two groups: pre-training and no pre-training. The pre-training group received a 10 minute and 52 second pre-training screencast that provided definitions, concepts and an overview of chemical equilibrium. After pre-training both group received the same 50-minute instructional lecture. After instruction, all students were given a chemical equilibrium concept post-test. Independent sample t-tests were conducted to examine differences in performance and intrinsic load. No significant differences in performance or intrinsic load, as measured by ratings of mental effort, were observed on the pre-test. Significant differences in performance, t(60)=3.70, p=.0005, and intrinsic load, t(60)=5.34, p=.0001, were observed on the post-test. A significant correlation between total performance scores and total mental effort ratings was also observed, r(60)=-0.44, p=.0003. Because no significant differences in prior knowledge were observed, it can be concluded that pre-training was successful at reducing intrinsic load. Moreover, a significant correlation between performance and mental effort strengthens the argument that performance measures can be used to approximate intrinsic cognitive load.

Opposing effects of perceptual versus working memory load on emotional distraction.

PubMed

Tavares, Tamara P; Logie, Kyle; Mitchell, Derek G V

2016-10-01

Throughout our day-to-day activities, we are subjected to numerous stimuli that compete for our attention; consequently, we must prioritize stimuli for further processing and influence over behaviour. Previous research has demonstrated that the extent to which task-irrelevant distractors are processed is mediated by the nature of the cognitive task, and the level of processing load. Importantly though, the interaction between cognitive task, processing load, and emotional distractor processing remains unclear. This is a particularly important question given the unique ways that emotion interacts with attention, and the fact that some other forms of processing load have been shown to reduce emotional distractor encoding. In the present study, participants were presented with emotional distractors during a perceptual and working memory task, under varying levels of load. In Experiment 1, we showed that the impact of emotional distractors on behaviour was reduced under conditions of high relative to low perceptual load. However, in sharp contrast, high working memory load was associated with increased emotional distraction. Importantly, these results were replicated in Experiment 2. Overall, the impact of processing load on emotional distraction varies according to the cognitive function being performed. These results raise the intriguing possibility that working memory operations deplete some of the cognitive resources needed to control the impact of emotion on behaviour. The findings, therefore, may have important implications for clinical populations featuring cognitive dysfunction and emotional dysregulation.

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…

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…

Oxidation of elemental mercury vapor over gamma-Al2O3 supported CuCl2 catalyst for mercury emissions control

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

Liu, Zhouyang; Liu, Xin; Lee, Joo-Youp

2015-09-01

In our previous studies, CuCl2 demonstrated excellent Hg(0) oxidation capability and holds potential for Hg(0) oxidation in coal-fired power plants. In this study, the properties and performances of CuCl2 supported onto gamma-Al2O3 with high surface area were investigated. From various characterization techniques using XPS, XAFS, XRD, TPR, SEM and TGA, the existence of multiple copper species was identified. At low CuCl2 loadings, CuCl2 forms copper aluminate species with gamma-Al2O3 and is inactive for Hg(0) oxidation. At high loadings, amorphous CuCl2 forms onto the gamma-Al2O3 surface, working as a redox catalyst for Hg(0) oxidation by consuming Cl to be converted intomore » CuCl and then being regenerated back into CuCl2 in the presence of O-2 and HCl gases. The 10%(wt) CuCl2/gamma-Al2O3 catalyst showed excellent Hg(0) oxidation performance and SO2 resistance at 140 degrees C under simulated flue gas conditions containing 6%(v) O-2 and 10 ppmv HCl. The oxidized Hg(0) in the form of HgCl2 has a high solubility in water and can be easily captured by other air pollution control systems such as wet scrubbers in coal-fired power plants. The CuCl2/gamma-Al2O3 catalyst can be used as a low temperature Hg(0) oxidation catalyst. (C) 2015 Elsevier B.V. All rights reserved.« less

Towards a cognitive resource limitations model of diminished expression in schizotypy.

PubMed

Cohen, Alex S; Morrison, Sean C; Brown, Laura A; Minor, Kyle S

2012-02-01

Diminished expression of speech is a pernicious feature of both schizophrenia and schizotypy--defined as the personality organization reflecting a putative genetic schizophrenia liability. As yet, the mechanism underlying diminished expression is unclear. We tested the hypothesis that diminished expression reflects a cognitive resource issue--that is, as cognitive resources are depleted, expression becomes diminished in individuals with psychometrically defined schizotypy. Acoustic analysis of natural speech was procured during experimentally manipulated baseline and high cognitive-load dual tasks and examined in 38 individuals with psychometrically defined schizotypy and 34 controls. For both groups, expression significantly decreased as a function of increased task demands, although there were no group differences in expression or magnitude of change across baseline to high cognitive-load conditions. Participants with self-reported constricted affect showed significant reductions in expression under high-load versus baseline speaking conditions relative to other schizotypal and control participants. Moreover, psychometrically defined schizotypal participants with poor cognitive performance on the high-load task, suggestive of depleted cognitive resources, also showed expressivity reductions compared with other participants. These findings suggest that diminished expression occurs as a function of limited cognitive resources in psychometrically defined schizotypy. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Effects on automatic attention due to exposure to pictures of emotional faces while performing Chinese word judgment tasks.

PubMed

Junhong, Huang; Renlai, Zhou; Senqi, Hu

2013-01-01

Two experiments were conducted to investigate the automatic processing of emotional facial expressions while performing low or high demand cognitive tasks under unattended conditions. In Experiment 1, 35 subjects performed low (judging the structure of Chinese words) and high (judging the tone of Chinese words) cognitive load tasks while exposed to unattended pictures of fearful, neutral, or happy faces. The results revealed that the reaction time was slower and the performance accuracy was higher while performing the low cognitive load task than while performing the high cognitive load task. Exposure to fearful faces resulted in significantly longer reaction times and lower accuracy than exposure to neutral faces on the low cognitive load task. In Experiment 2, 26 subjects performed the same word judgment tasks and their brain event-related potentials (ERPs) were measured for a period of 800 ms after the onset of the task stimulus. The amplitudes of the early component of ERP around 176 ms (P2) elicited by unattended fearful faces over frontal-central-parietal recording sites was significantly larger than those elicited by unattended neutral faces while performing the word structure judgment task. Together, the findings of the two experiments indicated that unattended fearful faces captured significantly more attention resources than unattended neutral faces on a low cognitive load task, but not on a high cognitive load task. It was concluded that fearful faces could automatically capture attention if residues of attention resources were available under the unattended condition.

Effects on Automatic Attention Due to Exposure to Pictures of Emotional Faces while Performing Chinese Word Judgment Tasks

PubMed Central

Junhong, Huang; Renlai, Zhou; Senqi, Hu

2013-01-01

Two experiments were conducted to investigate the automatic processing of emotional facial expressions while performing low or high demand cognitive tasks under unattended conditions. In Experiment 1, 35 subjects performed low (judging the structure of Chinese words) and high (judging the tone of Chinese words) cognitive load tasks while exposed to unattended pictures of fearful, neutral, or happy faces. The results revealed that the reaction time was slower and the performance accuracy was higher while performing the low cognitive load task than while performing the high cognitive load task. Exposure to fearful faces resulted in significantly longer reaction times and lower accuracy than exposure to neutral faces on the low cognitive load task. In Experiment 2, 26 subjects performed the same word judgment tasks and their brain event-related potentials (ERPs) were measured for a period of 800 ms after the onset of the task stimulus. The amplitudes of the early component of ERP around 176 ms (P2) elicited by unattended fearful faces over frontal-central-parietal recording sites was significantly larger than those elicited by unattended neutral faces while performing the word structure judgment task. Together, the findings of the two experiments indicated that unattended fearful faces captured significantly more attention resources than unattended neutral faces on a low cognitive load task, but not on a high cognitive load task. It was concluded that fearful faces could automatically capture attention if residues of attention resources were available under the unattended condition. PMID:24124486

Twenty years of load theory-Where are we now, and where should we go next?

PubMed

Murphy, Gillian; Groeger, John A; Greene, Ciara M

2016-10-01

Selective attention allows us to ignore what is task-irrelevant and focus on what is task-relevant. The cognitive and neural mechanisms that underlie this process are key topics of investigation in cognitive psychology. One of the more prominent theories of attention is perceptual load theory, which suggests that the efficiency of selective attention is dependent on both perceptual and cognitive load. It is now more than 20 years since the proposal of load theory, and it is a good time to evaluate the evidence in support of this influential model. The present article supplements and extends previous reviews (Lavie, Trends in Cognitive Sciences, 9, 75-82. doi: 10.1016/j.tics.2004.12.004 , 2005, Current Directions in Psychological Science, 19, 143-148. doi: 10.1177/0963721410370295 , 2010) by examining more recent research in what appears to be a rapidly expanding area. The article comprises five parts, examining (1) evidence for the effects of perceptual load on attention, (2) cognitive load, (3) individual differences under load, (4) alternative theories and criticisms, and (5) the future of load theory. We argue that the key next step for load theory will be the application of the model to real-world tasks. The potential benefits of applied attention research are numerous, and there is tentative evidence that applied research would provide strong support for the theory itself, as well as real-world benefits related to activities in which attention is crucial, such as driving and education.

Consolidation and restoration of memory traces in working memory.

PubMed

De Schrijver, Sébastien; Barrouillet, Pierre

2017-10-01

Consolidation is the process through which ephemeral sensory traces are transformed into more stable short-term memory traces. It has been shown that consolidation plays a crucial role in working memory (WM) performance, by strengthening memory traces that then better resist interference and decay. In a recent study, Bayliss, Bogdanovs, and Jarrold (Journal of Memory and Language, 81, 34-50, 2015) argued that this process is separate from the processes known to restore WM traces after degradation, such as attentional refreshing and verbal rehearsal. In the present study, we investigated the relationship between the two types of processes in the context of WM span tasks. Participants were presented with series of letters for serial recall, each letter being followed by four digits for parity judgment. Consolidation opportunity was manipulated by varying the delay between each letter and the first digit to be processed, while opportunities for restoration were manipulated by varying the pace at which the parity task had to be performed (i.e., its cognitive load, or CL). Increasing the time available for either consolidation or restoration resulted in higher WM spans, with some substitutability between the two processes. Accordingly, when consolidation time was added to restoration time in the calculation of CL, the new resulting index, called extended CL, proved a very good predictor of recall performance, a finding also observed when verbal rehearsal was prevented by articulatory suppression. This substitutability between consolidation and restoration suggests that both processes may rely on the same mechanisms.

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…

Cognitive task analysis: harmonizing tasks to human capacities.

PubMed

Neerincx, M A; Griffioen, E

1996-04-01

This paper presents the development of a cognitive task analysis that assesses the task load of jobs and provides indicators for the redesign of jobs. General principles of human task performance were selected and, subsequently, integrated into current task modelling techniques. The resulting cognitive task analysis centres around four aspects of task load: the number of actions in a period, the ratio between knowledge- and rule-based actions, lengthy uninterrupted actions, and momentary overloading. The method consists of three stages: (1) construction of a hierarchical task model, (2) a time-line analysis and task load assessment, and (3), if necessary, adjustment of the task model. An application of the cognitive task analysis in railway traffic control showed its benefits over the 'old' task load analysis of the Netherlands Railways. It provided a provisional standard for traffic control jobs, conveyed two load risks -- momentary overloading and underloading -- and resulted in proposals to satisfy the standard and to diminish the two load risk.

Asymmetric Spatial Processing Under Cognitive Load

PubMed Central

Naert, Lien; Bonato, Mario; Fias, Wim

2018-01-01

Spatial attention allows us to selectively process information within a certain location in space. Despite the vast literature on spatial attention, the effect of cognitive load on spatial processing is still not fully understood. In this study we added cognitive load to a spatial processing task, so as to see whether it would differentially impact upon the processing of visual information in the left versus the right hemispace. The main paradigm consisted of a detection task that was performed during the maintenance interval of a verbal working memory task. We found that increasing cognitive working memory load had a more negative impact on detecting targets presented on the left side compared to those on the right side. The strength of the load effect correlated with the strength of the interaction on an individual level. The implications of an asymmetric attentional bias with a relative disadvantage for the left (vs the right) hemispace under high verbal working memory (WM) load are discussed. PMID:29740371

Response-Conflict Moderates the Cognitive Control of Episodic and Contextual Load in Older Adults.

PubMed

Eich, Teal S; Rakitin, Brian C; Stern, Yaakov

2016-11-01

Decline in cognitive control is one of the primary cognitive changes in normal aging. Reaching a consensus regarding the nature of these age-related changes, however, is complicated by the complexity of cognitive control as a construct. Healthy older and younger adults participated in a multifactorial test of cognitive control. Within participants, the procedure varied as a function of the amount contextual load, episodic load, and response-conflict load present. We found that older adults showed impaired performance relative to younger adults. We also found, however, that the response selection process underlying the response-conflict manipulation was a major moderator of age-related differences in both the contextual and episodic load conditions-suggesting a hierarchical organization. These findings are consistent with previous findings, suggesting that deficits in cognitive control in older adults are directly related to the resolution of response-conflict and that other apparent deficits may be derivative upon the more basic response-conflict related deficit. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Trait susceptibility to worry modulates the effects of cognitive load on cognitive control: An ERP study.

PubMed

Owens, Max; Derakshan, Nazanin; Richards, Anne

2015-10-01

According to the predictions of attentional control theory (ACT) of anxiety (Eysenck, Derakshan, Santos, & Calvo, 2007), worry is a central feature of anxiety that interferes with the ability to inhibit distracting information necessary for successful task performance. However, it is unclear how such cognitive control deficits are modulated by task demands and by the emotionality of the distractors. A sample of 31 participants (25 female) completed a novel flanker task with emotional and neutral distractors under low- and high-cognitive-load conditions. The negative-going N2 event-related potential was measured to index participants' level of top-down resource allocation in the inhibition of distractors under high- and low-load conditions. Results showed N2 amplitudes were larger under high- compared with low-load conditions. In addition, under high but not low load, trait worry was associated with greater N2 amplitudes. Our findings support ACT predictions that trait worry adversely affects goal-directed behavior, and is associated with greater recruitment of cognitive resources to inhibit the impact of distracting information under conditions in which cognitive resources are taxed. (c) 2015 APA, all rights reserved).

Prefrontal activation may predict working-memory training gain in normal aging and mild cognitive impairment.

PubMed

Vermeij, Anouk; Kessels, Roy P C; Heskamp, Linda; Simons, Esther M F; Dautzenberg, Paul L J; Claassen, Jurgen A H R

2017-02-01

Cognitive training has been shown to result in improved behavioral performance in normal aging and mild cognitive impairment (MCI), yet little is known about the neural correlates of cognitive plasticity, or about individual differences in responsiveness to cognitive training. In this study, 21 healthy older adults and 14 patients with MCI received five weeks of adaptive computerized working-memory (WM) training. Before and after training, functional Near-Infrared Spectroscopy (fNIRS) was used to assess the hemodynamic response in left and right prefrontal cortex during performance of a verbal n-back task with varying levels of WM load. After training, healthy older adults demonstrated decreased prefrontal activation at high WM load, which may indicate increased processing efficiency. Although MCI patients showed improved behavioral performance at low WM load after training, no evidence was found for training-related changes in prefrontal activation. Whole-group analyses showed that a relatively strong hemodynamic response at low WM load was related to worse behavioral performance, while a relatively strong hemodynamic response at high WM load was related to higher training gain. Therefore, a 'youth-like' prefrontal activation pattern at older age may be associated with better behavioral outcome and cognitive plasticity.

Sensitive maintenance: a cognitive process underlying individual differences in memory for threatening information.

PubMed

Peters, Jan H; Hock, Michael; Krohne, Heinz Walter

2012-01-01

Dispositional styles of coping with threat influence memory for threatening information. In particular, sensitizers excel over repressors in their memory for threatening information after long retention intervals, but not after short ones. We therefore suggested that sensitizers, but not repressors, employ active maintenance processes during the retention interval to selectively retain threatening material. Sensitive maintenance was studied in 2 experiments in which participants were briefly exposed to threatening and nonthreatening pictures (Experiment 1, N = 128) or words (Experiment 2, N = 145). Following, we administered unannounced recognition tests before and after an intervening task that generated either high or low cognitive load, assuming that high cognitive load would impede sensitizers' memory maintenance of threatening material. Supporting our hypotheses, the same pattern of results was obtained in both experiments: Under low cognitive load, sensitizers forgot less threat material than repressors did; no such differences were observed under high cognitive load.

How Cognitive Load Influences Speakers' Choice of Referring Expressions.

PubMed

Vogels, Jorrig; Krahmer, Emiel; Maes, Alfons

2015-08-01

We report on two experiments investigating the effect of an increased cognitive load for speakers on the choice of referring expressions. Speakers produced story continuations to addressees, in which they referred to characters that were either salient or non-salient in the discourse. In Experiment 1, referents that were salient for the speaker were non-salient for the addressee, and vice versa. In Experiment 2, all discourse information was shared between speaker and addressee. Cognitive load was manipulated by the presence or absence of a secondary task for the speaker. The results show that speakers under load are more likely to produce pronouns, at least when referring to less salient referents. We take this finding as evidence that speakers under load have more difficulties taking discourse salience into account, resulting in the use of expressions that are more economical for themselves. © 2014 Cognitive Science Society, Inc.

Response of reinforced concrete and corrugated steel pipes to surface load

NASA Astrophysics Data System (ADS)

Lay, Geoff R.

Full-scale simulated live load tests were conducted in a controlled laboratory setting using a single-axle frame on 600-mm-inner-diameter reinforced concrete pipe (RCP) and corrugated steel pipe (CSP) when buried in dense, well-graded sand and gravel. Measurements of the RCP at nominal and working forces and beyond are reported for 0.3, 0.6 and 0.9 m of soil cover above the pipe crown. The RCP experienced no cracking when buried at 0.3 m under nominal and working CL-625 and CL-800 single-axle design loads. At these loads, the vertical contraction of the pipe diameter was less than 0.08 and 0.10 mm and the largest tensile strains in the pipe were 75 and 100 muepsilon (50-60% of the cracking strain), respectively. A 0.15 (+/-0.05)-mm-wide axial crack developed at the inner crown in the presence of a 6 kNm/m circumferential bending moment (70% of the theoretical ultimate moment capacity) at the fully factored CL-625 load. This crack did not propagate or widen from 3 series of cyclic load-unload tests. At 1300 kN of applied load the change in pipe diameter was less than 3.5 mm. Increasing soil cover from 0.3 to 0.6 to 0.9 m reduced the circumferential crown bending moment from 6.0 to 3.9 to 2.1 kNm/m, respectively, at 400 kN of axle load. A 1.6- and a 2.8-mm-thick CSP were also subjected to axle loading. No yielding or limit states occurred in the 1.6-mm-thick CSP when buried 0.9-m-deep. However, at 0.6 m of cover a 300 kN axle load caused local yielding at the pipe crown. Increasing soil cover from 0.6 to 0.9 m decreased the vertical diameter change from -3.0 to -1.2 mm and the crown bending moment from 0.7 to 0.2 kNm/m (75% and 20% of the yield moment), respectively, at a 250 kN axle load. Deflections of the thicker CSP were less than the thinner pipe below the CL-625 single-axle load, however further increases in applied load produced a greater response in the thicker pipe, likely due to a haunch support issue. Shallow axle loading produced a greater 3-dimensional response and a larger bending effect in both CSPs.

Cognitive Load Alters Neuronal Processing of Food Odors.

PubMed

Hoffmann-Hensel, Sonja Maria; Sijben, Rik; Rodriguez-Raecke, Rea; Freiherr, Jessica

2017-10-31

Obesity is a major health concern in modern societies. Although decreased physical activity and enhanced intake of high-caloric foods are important risk factors for developing obesity, human behavior during eating also plays a role. Previous studies have shown that distraction while eating increases food intake and leads to impaired processing of food stimuli. As olfaction is the most important sense involved in flavor perception, we used functional magnetic resonance imaging techniques to investigate the influence of cognitive memory load on olfactory perception and processing. Low- and high-caloric food odors were presented in combination with either low or high cognitive loads utilizing a memory task. The efficacy of the memory task was verified by a decrease in participant recall accuracy and an increase in skin conductance response during high cognitive load. Our behavioral data reveal a diminished perceived intensity for low- but not high-caloric food odors during high cognitive load. For low-caloric food odors, bilateral orbitofrontal (OFC) and piriform cortices (pirC) showed significantly lower activity during high compared with low cognitive load. For high-caloric food odors, a similar effect was established in pirC, but not in OFC. Insula activity correlates with higher intensity ratings found during the low cognitive load condition. We conclude lower activity in pirC and OFC to be responsible for diminished intensity perception, comparable to results in olfactory impaired patients and elderly. Further studies should investigate the influence of olfactory/gustatory intensities on food choices under distraction with special regards to low-caloric food. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Temporal pattern of emotions and cognitive load during simulation training and debriefing.

PubMed

Fraser, Kristin; McLaughlin, Kevin

2018-04-24

In the simulated clinical environment, there is a perceived benefit to the emotional activation experienced by learners; however, potential harm of excessive and/or negative emotions has also been hypothesized. An improved understanding of the emotional experiences of learners during each phase of the simulation session will inform instructional design. In this observational study, we asked 174 first-year medical students about their emotional state upon arrival to the simulation lab (t1). They were then trained on a standard simulation scenario, after which they rated their emotional state and perceived cognitive load (t2). After debriefing, we then asked them to again rate their emotions and cognitive load (t3). Students reported that their experience of tranquility (a positive and low-arousal state) dropped from pre-scenario (t1) to post-scenario (t2), and returned to baseline levels after debriefing (t3), from 0.69 (0.87) to 0.14 (0.78) to 0.62 (0.78). Post scenario cognitive load was rated to be moderately high at 6.62 (1.12) and scores increased after debriefing to 6.90 (1.05) d = 0.26, p < 0.001. Cognitive load was associated with the simultaneous measures of emotions at both t2 and t3. Participant emotions are significantly altered through the experience of medical simulation and emotions are associated with subjective ratings of cognitive load.

The effect of a concurrent working memory task and temporal offsets on the integration of auditory and visual speech information.

PubMed

Buchan, Julie N; Munhall, Kevin G

2012-01-01

Audiovisual speech perception is an everyday occurrence of multisensory integration. Conflicting visual speech information can influence the perception of acoustic speech (namely the McGurk effect), and auditory and visual speech are integrated over a rather wide range of temporal offsets. This research examined whether the addition of a concurrent cognitive load task would affect the audiovisual integration in a McGurk speech task and whether the cognitive load task would cause more interference at increasing offsets. The amount of integration was measured by the proportion of responses in incongruent trials that did not correspond to the audio (McGurk response). An eye-tracker was also used to examine whether the amount of temporal offset and the presence of a concurrent cognitive load task would influence gaze behavior. Results from this experiment show a very modest but statistically significant decrease in the number of McGurk responses when subjects also perform a cognitive load task, and that this effect is relatively constant across the various temporal offsets. Participant's gaze behavior was also influenced by the addition of a cognitive load task. Gaze was less centralized on the face, less time was spent looking at the mouth and more time was spent looking at the eyes, when a concurrent cognitive load task was added to the speech task.

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…

The Effects of Technical Illustrations on Cognitive Load.

ERIC Educational Resources Information Center

Purnell, Kenneth N.; And Others

1992-01-01

Outlines two theories of cognitive science that are relevant for instructional design, i.e., schema theory and cognitive load theory; and describes four experiments with Australian secondary school geography students that used these theories to examine the effects of splitting attention between technical illustrations and related text. (20…

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…

EEG Based Analysis of Cognitive Load Enhance Instructional Analysis

ERIC Educational Resources Information Center

Dan, Alex; Reiner, Miriam

2017-01-01

One of the recommended approaches in instructional design methods is to optimize the value of working memory capacity and avoid cognitive overload. Educational neuroscience offers novel processes and methodologies to analyze cognitive load based on physiological measures. Observing psychophysiological changes when they occur in response to the…

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…

Visual Search Load Effects on Age-Related Cognitive Decline: Evidence From the Yakumo Longitudinal Study.

PubMed

Hatta, Takeshi; Kato, Kimiko; Hotta, Chie; Higashikawa, Mari; Iwahara, Akihiko; Hatta, Taketoshi; Hatta, Junko; Fujiwara, Kazumi; Nagahara, Naoko; Ito, Emi; Hamajima, Nobuyuki

2017-01-01

The validity of Bucur and Madden's (2010) proposal that an age-related decline is particularly pronounced in executive function measures rather than in elementary perceptual speed measures was examined via the Yakumo Study longitudinal database. Their proposal suggests that cognitive load differentially affects cognitive abilities in older adults. To address their proposal, linear regression coefficients of 104 participants were calculated individually for the digit cancellation task 1 (D-CAT1), where participants search for a given single digit, and the D-CAT3, where they search for 3 digits simultaneously. Therefore, it can be conjectured that the D-CAT1 represents primarily elementary perceptual speed and low-visual search load task. whereas the D-CAT3 represents primarily executive function and high-visual search load task. Regression coefficients from age 65 to 75 for the D-CAT3 showed a significantly steeper decline than that for the D-CAT1, and a large number of participants showed this tendency. These results support the proposal by Brcur and Madden (2010) and suggest that the degree of cognitive load affects age-related cognitive decline.

Divided attention disrupts perceptual encoding during speech recognition.

PubMed

Mattys, Sven L; Palmer, Shekeila D

2015-03-01

Performing a secondary task while listening to speech has a detrimental effect on speech processing, but the locus of the disruption within the speech system is poorly understood. Recent research has shown that cognitive load imposed by a concurrent visual task increases dependency on lexical knowledge during speech processing, but it does not affect lexical activation per se. This suggests that "lexical drift" under cognitive load occurs either as a post-lexical bias at the decisional level or as a secondary consequence of reduced perceptual sensitivity. This study aimed to adjudicate between these alternatives using a forced-choice task that required listeners to identify noise-degraded spoken words with or without the addition of a concurrent visual task. Adding cognitive load increased the likelihood that listeners would select a word acoustically similar to the target even though its frequency was lower than that of the target. Thus, there was no evidence that cognitive load led to a high-frequency response bias. Rather, cognitive load seems to disrupt sublexical encoding, possibly by impairing perceptual acuity at the auditory periphery.

Fabrication and characterization of curcumin-loaded silk fibroin/P(LLA-CL) nanofibrous scaffold

NASA Astrophysics Data System (ADS)

Lian, Yuan; Zhan, Jian-Chao; Zhang, Kui-Hua; Mo, Xiu-Mei

2014-12-01

Curcumin exhibited excellent properties including antioxidant, antiinflammatory, antiviral, antibacterial, antifungal, anticancer, and anticoagulant activities. In this study, curcumin was incorporated into silk fibroin (SF)/poly(L-lactic acid- co-e-caprolactone) (P(LLA-CL)) nanofibrous scaffolds via electrospinning, and changes brought about by raising the curcumin content were observed: SEM images showed that the average nanofibrous diameter decreased at the beginning and then increased, and the nanofibers became uniform; FTIR showed that the conformation of SF transforming from random coil form to β-sheet structure had not been induced, while SF conformation converted to β-sheet after being treated with 75% ethanol vapor; XRD results confirmed that the crystal structure of (P(LLA-CL)) had been destroyed; The mechanical test illustrated that nanofibrous scaffolds still maintained good mechanical properties. Further, curcumin-loaded nanofibrous scaffolds were evaluated for drug release, antioxidant and antimicrobial activities in vitro. The results showed that curcumin presented a sustained release behavior from nanofibrous scaffolds and maintained its free radical scavenging ability, and such scaffolds could effectively inhibit S. aureus growth (> 95%). Thus, curcumin-loaded SF/P(LLA-CL) nanofibrous scaffolds might be potential candidates for wound dressing and tissue engineering scaffolds.

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.

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

Return to Learn: A review of cognitive rest versus rehabilitation after sports concussion.

PubMed

Eastman, Amelia; Chang, Douglas G

2015-01-01

Cognitive rest is the recommendation for all patients with acute sports concussion. A comprehensive literature search was conducted for the research question "What is the optimal cognitive load for patients with a sports concussion?" Seven studies met the inclusion criteria. The optimal cognitive load for patients after sports concussion is yet to be determined. Additional controlled trials of cognitive rehabilitation are needed to establish best clinical practice. The authors suggest memory training, cognitive behavioral therapy, and environmental interventions as areas of future research for sports concussion injuries.

Implementation and Assessment of Cognitive Load Theory (CLT) Based Questions in an Electronic Homework and Testing System

ERIC Educational Resources Information Center

Behmke, Derek A.; Atwood, Charles H.

2013-01-01

To a first approximation, human memory is divided into two parts, short-term and long-term. Cognitive Load Theory (CLT) attempts to minimize the short-term memory load while maximizing the memory available for transferring knowledge from short-term to long-term memory. According to CLT there are three types of load, intrinsic, extraneous, and…

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.

Food composition and acid-base balance: alimentary alkali depletion and acid load in herbivores.

PubMed

Kiwull-Schöne, Heidrun; Kiwull, Peter; Manz, Friedrich; Kalhoff, Hermann

2008-02-01

Alkali-enriched diets are recommended for humans to diminish the net acid load of their usual diet. In contrast, herbivores have to deal with a high dietary alkali impact on acid-base balance. Here we explore the role of nutritional alkali in experimentally induced chronic metabolic acidosis. Data were collected from healthy male adult rabbits kept in metabolism cages to obtain 24-h urine and arterial blood samples. Randomized groups consumed rabbit diets ad libitum, providing sufficient energy but variable alkali load. One subgroup (n = 10) received high-alkali food and approximately 15 mEq/kg ammonium chloride (NH4Cl) with its drinking water for 5 d. Another group (n = 14) was fed low-alkali food for 5 d and given approximately 4 mEq/kg NH4Cl daily for the last 2 d. The wide range of alimentary acid-base load was significantly reflected by renal base excretion, but normal acid-base conditions were maintained in the arterial blood. In rabbits fed a high-alkali diet, the excreted alkaline urine (pH(u) > 8.0) typically contained a large amount of precipitated carbonate, whereas in rabbits fed a low-alkali diet, both pH(u) and precipitate decreased considerably. During high-alkali feeding, application of NH4Cl likewise decreased pH(u), but arterial pH was still maintained with no indication of metabolic acidosis. During low-alkali feeding, a comparably small amount of added NH4Cl further lowered pH(u) and was accompanied by a significant systemic metabolic acidosis. We conclude that exhausted renal base-saving function by dietary alkali depletion is a prerequisite for growing susceptibility to NH4Cl-induced chronic metabolic acidosis in the herbivore rabbit.

Effect of cognitive load on articulation rate and formant frequencies during simulator flights.

PubMed

Huttunen, Kerttu H; Keränen, Heikki I; Pääkkönen, Rauno J; Päivikki Eskelinen-Rönkä, R; Leino, Tuomo K

2011-03-01

It was explored how three types of intensive cognitive load typical of military aviation (load on situation awareness, information processing, or decision-making) affect speech. The utterances of 13 male military pilots were recorded during simulated combat flights. Articulation rate was calculated from the speech samples, and the first formant (F1) and second formant (F2) were tracked from first-syllable short vowels in pre-defined phoneme environments. Articulation rate was found to correlate negatively (albeit with low coefficients) with loads on situation awareness and decision-making but not with changes in F1 or F2. Changes were seen in the spectrum of the vowels: mean F1 of front vowels usually increased and their mean F2 decreased as a function of cognitive load, and both F1 and F2 of back vowels increased. The strongest associations were seen between the three types of cognitive load and F1 and F2 changes in back vowels. Because fluent and clear radio speech communication is vital to safety in aviation and temporal and spectral changes may affect speech intelligibility, careful use of standard aviation phraseology and training in the production of clear speech during a high level of cognitive load are important measures that diminish the probability of possible misunderstandings. © 2011 Acoustical Society of America

Extending Cognitive Load Theory to Incorporate Working Memory Resource Depletion: Evidence from the Spacing Effect

ERIC Educational Resources Information Center

Chen, Ouhao; Castro-Alonso, Juan C.; Paas, Fred; Sweller, John

2018-01-01

Depletion of limited working memory resources may occur following extensive mental effort resulting in decreased performance compared to conditions requiring less extensive mental effort. This "depletion effect" can be incorporated into cognitive load theory that is concerned with using the properties of human cognitive architecture,…

Science Teaching Based on Cognitive Load Theory: Engaged Students, but Cognitive Deficiencies

ERIC Educational Resources Information Center

Meissner, Barbara; Bogner, Franz X.

2012-01-01

To improve science learning under demanding conditions, we designed an out-of-school lesson in compliance with cognitive load theory (CLT). We extracted student clusters based on individual effectiveness, and compared instructional efficiency, mental effort, and persistence of learning. The present study analyses students' engagement. 50.0% of our…

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…

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…

Behavioral and cognitive effects of tyrosine intake in healthy human adults.

PubMed

Hase, Adrian; Jung, Sophie E; aan het Rot, Marije

2015-06-01

The amino acid tyrosine is the precursor to the catecholamine neurotransmitters dopamine and norepinephrine. Increasing tyrosine uptake may positively influence catecholamine-related psychological functioning. We conducted a systematic review to examine the effects of tyrosine on behavior and cognition. Fifteen studies were reviewed. All studies except one involved tyrosine loading during a single test session. In most behavioral studies, there were no significant effects of tyrosine on exercise performance. In contrast, cognitive studies employing neuropsychological measures found that tyrosine loading acutely counteracts decrements in working memory and information processing that are induced by demanding situational conditions such as extreme weather or cognitive load. The buffering effects of tyrosine on cognition may be explained by tyrosine's ability to neutralize depleted brain catecholamine levels. There is evidence that tyrosine may benefit healthy individuals exposed to demanding situational conditions. For future research we recommend moving from studying the acute effects of a single tyrosine load in small samples to studying the behavioral and cognitive effects of tyrosine in larger groups over multiple weeks. Copyright © 2015 Elsevier Inc. All rights reserved.

Role of GSK-3β in isoflurane-induced neuroinflammation and cognitive dysfunction in aged rats.

PubMed

Li, Shi-yong; Chen, Xin; Chen, Ye-ling; Tan, Lei; Zhao, Yi-lin; Wang, Jin-tao; Xiang, Qiang; Luo, Ai-lin

2013-08-01

This study investigated the role of glycogen synthase kinase-3β (GSK-3β) in isoflurane-induced neuroinflammation and cognitive dysfunction in aged rats. The hippocampi were dissected from aged rats which had been intraperitoneally administered lithium chloride (LiCl, 100 mg/kg) and then exposed to 1.4% isoflurane for 6 h. The expression of GSK-3β was detected by Western blotting. The mRNA and protein expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were measured by real-time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. Morris water maze was employed to detect spatial memory ability of rats. The results revealed that the level of GSK-3β was upregulated after isofurane exposure. Real-time PCR analysis demonstrated that isoflurane anesthesia increased mRNA levels of TNF-α, IL-1β and IL-6, which was consistent with the ELISA results. However, these changes were reversed by prophylactic LiCl, a non-selective inhibitor of GSK-3β. Additionally, we discovered that LiCl alleviated isoflurane-induced cognitive impairment in aged rats. Furthermore, the role of GSK-3β in isoflurae-induced neuroinflammation and cognitive dysfunction was associated with acetylation of NF-κB p65 (Lys310). In conclusion, these results suggested that GSK-3β is associated with isoflurane-induced upregulation of proinflammatory cytokines and cognitive disorder in aged rats.

Automatic Ability Attribution after Failure: A Dual Process View of Achievement Attribution

PubMed Central

Sakaki, Michiko; Murayama, Kou

2013-01-01

Causal attribution has been one of the most influential frameworks in the literature of achievement motivation, but previous studies considered achievement attribution as relatively deliberate and effortful processes. In the current study, we tested the hypothesis that people automatically attribute their achievement failure to their ability, but reduce the ability attribution in a controlled manner. To address this hypothesis, we measured participants’ causal attribution belief for their task failure either under the cognitive load (load condition) or with full attention (no-load condition). Across two studies, participants attributed task performance to their ability more in the load than in the no-load condition. The increased ability attribution under cognitive load further affected intrinsic motivation. These results indicate that cognitive resources available after feedback play crucial roles in determining causal attribution belief, as well as achievement motivations. PMID:23667576

Automatic ability attribution after failure: a dual process view of achievement attribution.

PubMed

Sakaki, Michiko; Murayama, Kou

2013-01-01

Causal attribution has been one of the most influential frameworks in the literature of achievement motivation, but previous studies considered achievement attribution as relatively deliberate and effortful processes. In the current study, we tested the hypothesis that people automatically attribute their achievement failure to their ability, but reduce the ability attribution in a controlled manner. To address this hypothesis, we measured participants' causal attribution belief for their task failure either under the cognitive load (load condition) or with full attention (no-load condition). Across two studies, participants attributed task performance to their ability more in the load than in the no-load condition. The increased ability attribution under cognitive load further affected intrinsic motivation. These results indicate that cognitive resources available after feedback play crucial roles in determining causal attribution belief, as well as achievement motivations.

Contemporary Accounts of the Cognition/Language Relationship: Implications for Speech-Language Clinicians.

ERIC Educational Resources Information Center

Rice, Mabel L.

1983-01-01

A review of research on how cognition relates to language in children with language impairments discusses terminology and analyzes the basic mapping problem. Evidence for a variety of hypotheses related to the issue are examined. (CL)

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…

Perioperative Embolization Load and S-100β Do Not Predict Cognitive Outcome after Carotid Revascularization.

PubMed

Plessers, Maarten; Van Herzeele, Isabelle; Hemelsoet, Dimitri; Vingerhoets, Guy; Vermassen, Frank

2016-10-01

Cognitive changes after carotid revascularization have been reported in 10-20% of patients. The etiology of cognitive impairments remains largely unknown. This study evaluates the predictive value of S-100β serum values and perioperative microembolization on cognition after carotid revascularization. Forty-six patients with significant carotid stenosis underwent carotid endarterectomy (CEA, n = 26), transfemoral carotid artery stenting with distal protection (CASdp, n = 10), or transcervical carotid stenting with dynamic flow reversal (CASfr, n = 10). Twenty-six matched vascular patients without carotid stenosis were recruited as controls. All patients underwent comprehensive cognitive testing on the day before and 1 month after carotid revascularization. S-100β analysis was performed in 31 cases pre-, peri-, and 2, 6, and 24 hr after carotid surgery, and in 25 patients transcranial Doppler monitoring was done during surgery. In the 3 treatment groups similar transient increases in S-100β values were observed. CASdp was associated with a higher embolic load than CEA and CASfr, while CEA was also associated with less microembolization than CASfr. Cognitive improvement or deterioration could not be predicted by S-100β or perioperative embolic load for any of the investigated cognitive domains. Cognitive deterioration could not be predicted using perioperative embolic load and S-100β changes. A similar inverted u-curve of the S-100β levels was observed in the 3 groups and may be caused by impairment in the blood-brain barrier during intervention, and not due to cerebral infarction. Distal protection CAS is associated with a higher embolic load than transcervical CAS using dynamic flow reversal and CEA, but the long-term impact of this higher embolic load is yet unknown. Perfusion-related measures seem promising in their ability to predict cognitive decline. Copyright © 2016 Elsevier Inc. All rights reserved.

In search for instructional techniques to maximize the use of germane cognitive resources: A case of teaching complex tasks in physics

NASA Astrophysics Data System (ADS)

Sliva, Yekaterina

The purpose of this study was to introduce an instructional technique for teaching complex tasks in physics, test its effectiveness and efficiency, and understand cognitive processes taking place in learners' minds while they are exposed to this technique. The study was based primarily on cognitive load theory (CLT). CLT determines the amount of total cognitive load imposed on a learner by a learning task as combined intrinsic (invested in comprehending task complexity) and extraneous (wasteful) cognitive load. Working memory resources associated with intrinsic cognitive load are defined as germane resources caused by element interactivity that lead to learning, in contrast to extraneous working memory resources that are devoted to dealing with extraneous cognitive load. However, the amount of learner's working memory resources actually devoted to a task depends on how well the learner is engaged in the learning environment. Since total cognitive load has to stay within limits of working memory capacity, both extraneous and intrinsic cognitive load need to be reduced. In order for effective learning to occur, the use of germane cognitive resources should be maximized. In this study, the use of germane resources was maximized for two experimental groups by providing a learning environment that combined problem-solving procedure with prompts to self-explain with and without completion problems. The study tested three hypotheses and answered two research questions. The first hypothesis predicting that experimental treatments would reduce total cognitive load was not supported. The second hypothesis predicting that experimental treatments would increase performance was supported for the self-explanation group only. The third hypothesis that tested efficiency measure as adopted from Paas and van Merrienboer (1993) was not supported. As for the research question of whether the quality of self-explanations would change with time for the two experimental conditions, it was determined that time had a positive effect on such quality. The research question that investigated learners' attitudes towards the instructions revealed that experimental groups understood the main idea behind the suggested technique and positively reacted to it. The results of the study support the conclusions that (a) prompting learners to self-explain while independently solving problems can increase performance, especially on far transfer questions; (b) better performance is achieved in combination with increased mental effort; (c) self-explanations do not increase time on task; and (d) quality of self-explanations can be improved with time. Results based on the analyses of learners' attitudes further support that learners in the experimental groups understood the main idea behind the suggested techniques and positively reacted to them. The study also raised concern about application of efficiency formula for instructional conditions that increase both performance and mental effort in CLT. As a result, an alternative model was suggested to explain the relationship between performance and mental effort based on Yerkes-Dodson law (1908). Keywords: instructional design, cognitive load, complex tasks, problem-solving, self-explanation.

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.

Explorations in Cooperative Systems: Thinking Collectively to Learn, Learning Individually to Think

DTIC Science & Technology

1989-12-01

indicates that the CL research lacks sufficient experimental controls, as well as, fails to use current theories associated with cognitiv-e approaches...comparing/contrasting some of the differences between CL and GPS. Finally, examples of successful CL are given to show the transition from theory to...Schmuck, 1985). For example, Stodolsky (1984) differentiates peer-work groups from teacher- led groups. She suggests that there are five types of

Current limiting remote power control module

NASA Technical Reports Server (NTRS)

Hopkins, Douglas C.

1990-01-01

The power source for the Space Station Freedom will be fully utilized nearly all of the time. As such, any loads on the system will need to operate within expected limits. Should any load draw an inordinate amount of power, the bus voltage for the system may sag and disrupt the operation of other loads. To protect the bus and loads some type of power interface between the bus and each load must be provided. This interface is most crucial when load faults occur. A possible system configuration is presented. The proposed interface is the Current Limiting Remote Power Controller (CL-RPC). Such an interface should provide the following power functions: limit overloading and resulting undervoltage; prevent catastrophic failure and still provide for redundancy management within the load; minimize cable heating; and provide accurate current measurement. A functional block diagram of the power processing stage of a CL-RPC is included. There are four functions that drive the circuit design: rate control of current; current sensing; the variable conductance switch (VCS) technology; and the algorithm used for current limiting. Each function is discussed separately.

The effects of cognitive load on attention control in subclinical anxiety and Generalized Anxiety Disorder

PubMed Central

Najmi, Sadia; Amir, Nader; Frosio, Kristen E.; Ayers, Catherine

2014-01-01

Poor regulation of emotions may involve impaired attention control. In the current paper, we report the results of two studies examining the interaction of anxiety, attention control, and cognitive load. In Study I, using a performance-based task to assess attention control, we examined whether anxiety is associated with impaired attention control, and whether these effects are influenced by working memory load. In Study II we examined these effects in patients with a diagnosis of Generalized Anxiety Disorder (GAD) compared to non-anxious control (NAC) participants. Results of Study I showed that high anxiety was associated with increased attention control, that is decreased interference from distractors, but only under high cognitive load. These results were replicated in Study II such that individuals with GAD showed increased attention control relative to NACs, but only under high cognitive load. These results help clarify previous predictions regarding the effect of anxiety on attention control. PMID:25355423

Pupillary response to complex interdependent tasks: A cognitive-load theory perspective.

PubMed

Mitra, Ritayan; McNeal, Karen S; Bondell, Howard D

2017-10-01

Pupil dilation is known to indicate cognitive load. In this study, we looked at the average pupillary responses of a cohort of 29 undergraduate students during graphical problem solving. Three questions were asked, based on the same graphical input. The questions were interdependent and comprised multiple steps. We propose a novel way of analyzing pupillometry data for such tasks on the basis of eye fixations, a commonly used eyetracking parameter. We found that pupil diameter increased during the solution process. However, pupil diameter did not always reflect the expected cognitive load. This result was studied within a cognitive-load theory model. Higher-performing students showed evidence of germane load and schema creation, indicating use of the interdependent nature of the tasks to inform their problem-solving process. However, lower-performing students did not recognize the interdependent nature of the tasks and solved each problem independently, which was expressed in a markedly different pupillary response pattern. We discuss the import of our findings for instructional design.

Evidence for social working memory from a parametric functional MRI study.

PubMed

Meyer, Meghan L; Spunt, Robert P; Berkman, Elliot T; Taylor, Shelley E; Lieberman, Matthew D

2012-02-07

Keeping track of various amounts of social cognitive information, including people's mental states, traits, and relationships, is fundamental to navigating social interactions. However, to date, no research has examined which brain regions support variable amounts of social information processing ("social load"). We developed a social working memory paradigm to examine the brain networks sensitive to social load. Two networks showed linear increases in activation as a function of increasing social load: the medial frontoparietal regions implicated in social cognition and the lateral frontoparietal system implicated in nonsocial forms of working memory. Of these networks, only load-dependent medial frontoparietal activity was associated with individual differences in social cognitive ability (trait perspective-taking). Although past studies of nonsocial load have uniformly found medial frontoparietal activity decreases with increasing task demands, the current study demonstrates these regions do support increasing mental effort when such effort engages social cognition. Implications for the etiology of clinical disorders that implicate social functioning and potential interventions are discussed.

Vestibular control of standing balance is enhanced with increased cognitive load.

PubMed

McGeehan, Michael A; Woollacott, Marjorie H; Dalton, Brian H

2017-04-01

When cognitive load is elevated during a motor task, cortical inhibition and reaction time are increased; yet, standing balance control is often unchanged. This disconnect is likely explained by compensatory mechanisms within the balance system such as increased sensitivity of the vestibulomotor pathway. This study aimed to determine the effects of increased cognitive load on the vestibular control of standing balance. Participants stood blindfolded on a force plate with their head facing left and arms relaxed at their sides for two trials while exposed to continuous electrical vestibular stimulation (EVS). Participants either stood quietly or executed a cognitive task (double-digit arithmetic). Surface electromyography (EMG) and anterior-posterior ground-body forces (APF) were measured in order to evaluate vestibular-evoked balance responses in the frequency (coherence and gain) and time (cumulant density) domains. Total distance traveled for anterior-posterior center of pressure (COP) was assessed as a metric of balance variability. Despite similar distances traveled for COP, EVS-medial gastrocnemius (MG) EMG and EVS-APF coherence and EVS-TA EMG and EVS-MG EMG gain were elevated for multiple frequencies when standing with increased cognitive load. For the time domain, medium-latency peak amplitudes increased by 13-54% for EVS-APF and EVS-EMG relationships with the cognitive task compared to without. Peak short-latency amplitudes were unchanged. These results indicate that reliance on vestibular control of balance is enhanced when cognitive load is elevated. This augmented neural strategy may act to supplement divided cortical processing resources within the balance system and compensate for the acute neuromuscular modifications associated with increased cognitive demand.

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…

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…

Cognitive Evaluation Theory: The Effects of External Rewards on Intrinsic Motivation of Gifted Students.

ERIC Educational Resources Information Center

Rogers, Brenda T.

1985-01-01

E. Deci's cognitive evaluation theory, which suggests that external rewards undermine intrinsic interest in an activity, is applied to the decline of instrinsic motivation in gifted students. Implications for feedback, rewards, and teacher role are noted. (CL)

Cognitive Load Measurement in a Virtual Reality-based Driving System for Autism Intervention

PubMed Central

Zhang, Lian; Wade, Joshua; Bian, Dayi; Fan, Jing; Swanson, Amy; Weitlauf, Amy; Warren, Zachary; Sarkar, Nilanjan

2016-01-01

Autism Spectrum Disorder (ASD) is a highly prevalent neurodevelopmental disorder with enormous individual and social cost. In this paper, a novel virtual reality (VR)-based driving system was introduced to teach driving skills to adolescents with ASD. This driving system is capable of gathering eye gaze, electroencephalography, and peripheral physiology data in addition to driving performance data. The objective of this paper is to fuse multimodal information to measure cognitive load during driving such that driving tasks can be individualized for optimal skill learning. Individualization of ASD intervention is an important criterion due to the spectrum nature of the disorder. Twenty adolescents with ASD participated in our study and the data collected were used for systematic feature extraction and classification of cognitive loads based on five well-known machine learning methods. Subsequently, three information fusion schemes—feature level fusion, decision level fusion and hybrid level fusion—were explored. Results indicate that multimodal information fusion can be used to measure cognitive load with high accuracy. Such a mechanism is essential since it will allow individualization of driving skill training based on cognitive load, which will facilitate acceptance of this driving system for clinical use and eventual commercialization. PMID:28966730

Cognitive Load Measurement in a Virtual Reality-based Driving System for Autism Intervention.

PubMed

Zhang, Lian; Wade, Joshua; Bian, Dayi; Fan, Jing; Swanson, Amy; Weitlauf, Amy; Warren, Zachary; Sarkar, Nilanjan

2017-01-01

Autism Spectrum Disorder (ASD) is a highly prevalent neurodevelopmental disorder with enormous individual and social cost. In this paper, a novel virtual reality (VR)-based driving system was introduced to teach driving skills to adolescents with ASD. This driving system is capable of gathering eye gaze, electroencephalography, and peripheral physiology data in addition to driving performance data. The objective of this paper is to fuse multimodal information to measure cognitive load during driving such that driving tasks can be individualized for optimal skill learning. Individualization of ASD intervention is an important criterion due to the spectrum nature of the disorder. Twenty adolescents with ASD participated in our study and the data collected were used for systematic feature extraction and classification of cognitive loads based on five well-known machine learning methods. Subsequently, three information fusion schemes-feature level fusion, decision level fusion and hybrid level fusion-were explored. Results indicate that multimodal information fusion can be used to measure cognitive load with high accuracy. Such a mechanism is essential since it will allow individualization of driving skill training based on cognitive load, which will facilitate acceptance of this driving system for clinical use and eventual commercialization.

Late-Onset Alzheimer's Disease Polygenic Risk Profile Score Predicts Hippocampal Function.

PubMed

Xiao, Ena; Chen, Qiang; Goldman, Aaron L; Tan, Hao Yang; Healy, Kaitlin; Zoltick, Brad; Das, Saumitra; Kolachana, Bhaskar; Callicott, Joseph H; Dickinson, Dwight; Berman, Karen F; Weinberger, Daniel R; Mattay, Venkata S

2017-11-01

We explored the cumulative effect of several late-onset Alzheimer's disease (LOAD) risk loci using a polygenic risk profile score (RPS) approach on measures of hippocampal function, cognition, and brain morphometry. In a sample of 231 healthy control subjects (19-55 years of age), we used an RPS to study the effect of several LOAD risk loci reported in a recent meta-analysis on hippocampal function (determined by its engagement with blood oxygen level-dependent functional magnetic resonance imaging during episodic memory) and several cognitive metrics. We also studied effects on brain morphometry in an overlapping sample of 280 subjects. There was almost no significant association of LOAD-RPS with cognitive or morphometric measures. However, there was a significant negative relationship between LOAD-RPS and hippocampal function (familywise error [small volume correction-hippocampal region of interest] p < .05). There were also similar associations for risk score based on APOE haplotype, and for a combined LOAD-RPS + APOE haplotype risk profile score (p < .05 familywise error [small volume correction-hippocampal region of interest]). Of the 29 individual single nucleotide polymorphisms used in calculating LOAD-RPS, variants in CLU, PICALM, BCL3, PVRL2, and RELB showed strong effects (p < .05 familywise error [small volume correction-hippocampal region of interest]) on hippocampal function, though none survived further correction for the number of single nucleotide polymorphisms tested. There is a cumulative deleterious effect of LOAD risk genes on hippocampal function even in healthy volunteers. The effect of LOAD-RPS on hippocampal function in the relative absence of any effect on cognitive and morphometric measures is consistent with the reported temporal characteristics of LOAD biomarkers with the earlier manifestation of synaptic dysfunction before morphometric and cognitive changes. Copyright © 2017 Society of Biological Psychiatry. All rights reserved.

Anterior paracingulate and cingulate cortex mediates the effects of cognitive load on speech sound discrimination.

PubMed

Gennari, Silvia P; Millman, Rebecca E; Hymers, Mark; Mattys, Sven L

2018-06-12

Perceiving speech while performing another task is a common challenge in everyday life. How the brain controls resource allocation during speech perception remains poorly understood. Using functional magnetic resonance imaging (fMRI), we investigated the effect of cognitive load on speech perception by examining brain responses of participants performing a phoneme discrimination task and a visual working memory task simultaneously. The visual task involved holding either a single meaningless image in working memory (low cognitive load) or four different images (high cognitive load). Performing the speech task under high load, compared to low load, resulted in decreased activity in pSTG/pMTG and increased activity in visual occipital cortex and two regions known to contribute to visual attention regulation-the superior parietal lobule (SPL) and the paracingulate and anterior cingulate gyrus (PaCG, ACG). Critically, activity in PaCG/ACG was correlated with performance in the visual task and with activity in pSTG/pMTG: Increased activity in PaCG/ACG was observed for individuals with poorer visual performance and with decreased activity in pSTG/pMTG. Moreover, activity in a pSTG/pMTG seed region showed psychophysiological interactions with areas of the PaCG/ACG, with stronger interaction in the high-load than the low-load condition. These findings show that the acoustic analysis of speech is affected by the demands of a concurrent visual task and that the PaCG/ACG plays a role in allocating cognitive resources to concurrent auditory and visual information. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Domain-general involvement of the posterior frontolateral cortex in time-based resource-sharing in working memory: An fMRI study.

PubMed

Vergauwe, Evie; Hartstra, Egbert; Barrouillet, Pierre; Brass, Marcel

2015-07-15

Working memory is often defined in cognitive psychology as a system devoted to the simultaneous processing and maintenance of information. In line with the time-based resource-sharing model of working memory (TBRS; Barrouillet and Camos, 2015; Barrouillet et al., 2004), there is accumulating evidence that, when memory items have to be maintained while performing a concurrent activity, memory performance depends on the cognitive load of this activity, independently of the domain involved. The present study used fMRI to identify regions in the brain that are sensitive to variations in cognitive load in a domain-general way. More precisely, we aimed at identifying brain areas that activate during maintenance of memory items as a direct function of the cognitive load induced by both verbal and spatial concurrent tasks. Results show that the right IFJ and bilateral SPL/IPS are the only areas showing an increased involvement as cognitive load increases and do so in a domain general manner. When correlating the fMRI signal with the approximated cognitive load as defined by the TBRS model, it was shown that the main focus of the cognitive load-related activation is located in the right IFJ. The present findings indicate that the IFJ makes domain-general contributions to time-based resource-sharing in working memory and allowed us to generate the novel hypothesis by which the IFJ might be the neural basis for the process of rapid switching. We argue that the IFJ might be a crucial part of a central attentional bottleneck in the brain because of its inability to upload more than one task rule at once. Copyright © 2015 Elsevier Inc. All rights reserved.

SU33. Load-Sensitive Impairment of Working Memory for Biological Motion in Schizophrenia

PubMed Central

Lee, Hannah; Kim, Jejoong

2017-01-01

Abstract Background: Patients with schizophrenia (SZ) exhibit various deficits that may affect social functioning. The impairments in perceptual processing (eg, motion perception) and in higher cognitive processing such as working memory (WM), as well as deficits in social cognition, need to be closely examined in order to understand dysfunctions in social environments. However, comprehensive research conducted to date that takes these aspects into consideration all together is limited. Biological motion (BM) is a unique motion stimulus containing rich social information. Therefore, BM is optimal for our aim in this study to scrutinize how the dysfunctions in the cognitive processing of aforementioned 3 aspects (motion perception, WM, and social cognition) would be manifested in SZ, in a single experimental design. Methods: In the present study, we used BM in a delayed-response task for measuring WM. Non-BM motion stimulus (pairwise-shuffled motion or PSM) and polygons were also used for comparisons. One of the 3 types of stimuli was presented in each trial. After 12-second delays, 2 probes were shown, and the participants were asked to indicate whether one of them was identical to the memory item or whether both were novel. The number of memory items was either one (low load) or 2 (high load). Results: Overall, SZ performed worse than healthy controls (CO) regardless of the type of stimuli and memory loads, which is consistent with previous WM research. Across the low and high load conditions, CO were more accurate in recognizing BM than PSM, indicating that BM may have a facilitating effect for the encoding process involved in WM. Interestingly, SZ had similar accuracy patterns to that of CO in the low load condition. The BM facilitation effect, however, disappeared in the high load condition, yielding a significant interaction among group, stimulus type, and memory loads. These results suggest that BM, as a socially relevant stimulus, can facilitate encoding and/or maintenance to benefit WM performance in CO and that his effect is also partially valid among SZ. That is, SZ seem to successfully process the meaning of the stimulus when memory load is low. However, the ability is vulnerable to the increase of cognitive load in SZ, implying the presence of inefficiencies in the connections between perceptual and cognitive processes and/or limits in the capacity to process social information. Conclusion: The present study suggests that the intricate interaction among perceptual, cognitive, and social processes needs to be considered to explain cognitive deficits related with social dysfunction in schizophrenia. This study was supported by National Research Foundation of Korea.

The Relationship of Scaffolding on Cognitive Load in an Online Self-Regulated Learning Environment

ERIC Educational Resources Information Center

Danilenko, Eugene Paul

2010-01-01

Scaffolding learners in self-regulated learning environments is a topic of increasing importance as implementation of online learning grows. Since cognitive overload in hypermedia environments can be a problem for some learners, instructional design strategies can be used to decrease extraneous load or encourage germane load in order to help…

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'…

Changes in Predictive Task Switching with Age and with Cognitive Load.

PubMed

Levy-Tzedek, Shelly

2017-01-01

Predictive control of movement is more efficient than feedback-based control, and is an important skill in everyday life. We tested whether the ability to predictively control movements of the upper arm is affected by age and by cognitive load. A total of 63 participants were tested in two experiments. In both experiments participants were seated, and controlled a cursor on a computer screen by flexing and extending their dominant arm. In Experiment 1, 20 young adults and 20 older adults were asked to continuously change the frequency of their horizontal arm movements, with the goal of inducing an abrupt switch between discrete movements (at low frequencies) and rhythmic movements (at high frequencies). We tested whether that change was performed based on a feed-forward (predictive) or on a feedback (reactive) control. In Experiment 2, 23 young adults performed the same task, while being exposed to a cognitive load half of the time via a serial subtraction task. We found that both aging and cognitive load diminished, on average, the ability of participants to predictively control their movements. Five older adults and one young adult under a cognitive load were not able to perform the switch between rhythmic and discrete movement (or vice versa). In Experiment 1, 40% of the older participants were able to predictively control their movements, compared with 70% in the young group. In Experiment 2, 48% of the participants were able to predictively control their movements with a cognitively loading task, compared with 70% in the no-load condition. The ability to predictively change a motor plan in anticipation of upcoming changes may be an important component in performing everyday functions, such as safe driving and avoiding falls.

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

PubMed

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

2015-08-01

Interest in applying cognitive load theory in health care simulation is growing. This line of inquiry requires measures that are sensitive to changes in cognitive load arising from different instructional designs. Recently, mental effort ratings and secondary task performance have shown promise as measures of cognitive load in health care simulation. We investigate the sensitivity of these measures to predicted differences in intrinsic load arising from variations in task complexity and learner expertise during simulation-based surgical skills training. We randomly assigned 28 novice medical students to simulation training on a simple or complex surgical knot-tying task. Participants completed 13 practice trials, interspersed with computer-based video instruction. On trials 1, 5, 9 and 13, knot-tying performance was assessed using time and movement efficiency measures, and cognitive load was assessed using subjective rating of mental effort (SRME) and simple reaction time (SRT) on a vibrotactile stimulus-monitoring secondary task. Significant improvements in knot-tying performance (F(1.04,24.95)  = 41.1, p < 0.001 for movements; F(1.04,25.90)  = 49.9, p < 0.001 for time) and reduced cognitive load (F(2.3,58.5)  = 57.7, p < 0.001 for SRME; F(1.8,47.3)  = 10.5, p < 0.001 for SRT) were observed in both groups during training. The simple-task group demonstrated superior knot tying (F(1,24)  = 5.2, p = 0.031 for movements; F(1,24)  = 6.5, p = 0.017 for time) and a faster decline in SRME over the first five trials (F(1,26)  = 6.45, p = 0.017) compared with their peers. Although SRT followed a similar pattern, group differences were not statistically significant. Both secondary task performance and mental effort ratings are sensitive to changes in intrinsic load among novices engaged in simulation-based learning. These measures can be used to track cognitive load during skills training. Mental effort ratings are also sensitive to small differences in intrinsic load arising from variations in the physical complexity of a simulation task. The complementary nature of these subjective and objective measures suggests their combined use is advantageous in simulation instructional design research. © 2015 John Wiley & Sons Ltd.

A modified approach for estimating the aquatic critical load of acid deposition in northern Saskatchewan, Canada

NASA Astrophysics Data System (ADS)

Whitfield, Colin J.; Mowat, Aidan C.; Scott, Kenneth A.; Watmough, Shaun A.

2016-12-01

Acid-sensitive ecosystems are found in northern Saskatchewan, which lies downwind of major sulphur (S) and nitrogen (N) emissions sources associated with the oil sands extraction industry. In order to protect these ecosystems against acidification, tolerance to acid deposition must be quantified. The suitability of the central empirical relationship used in the Steady-State Water Chemistry (SSWC) model to predict historical sulphate (SO4) concentrations was investigated, and an alternate approach for determining aquatic critical loads of acidity (CL(A)) was employed for the study lakes (n = 260). Critical loads of acidity were often low, with median values of 12-16 mmolc m-2 yr-1, with the lower value reflecting a region-specific limit for acid-neutralizing capacity identified in this study. Uncertain levels of atmospheric deposition in the region, however, are problematic for characterizing acidification risk. Accurate S and chloride (Cl) deposition are needed to identify catchment sources (and sinks) of these elements in the new approach for CL(A) calculation. Likewise, accurate depiction of atmospheric deposition levels can prove useful for evaluation of lake runoff estimates on which estimates of CL(A) are contingent. While CL(A) are low and exceedance may occur according to projected increases in S deposition in the near-term, S retention appears to be an important feature in many catchments and risk of acidification may be overstated should long-term S retention be occurring in peatlands.

Mechanical loading influences the viscoelastic performance of the resin-carious dentin complex.

PubMed

Toledano, Manuel; Osorio, Raquel; López-López, Modesto T; Aguilera, Fátima S; García-Godoy, Franklin; Toledano-Osorio, Manuel; Osorio, Estrella

2017-04-04

The aim of this study was to evaluate the changes in the mechanical behavior and bonding capability of Zn-doped resin-infiltrated caries-affected dentin interfaces. Dentin surfaces were treated with 37% phosphoric acid (PA) followed by application of a dentin adhesive, single bond (SB) (PA+SB) or by 0.5 M ethylenediaminetetraacetic acid (EDTA) followed by SB (EDTA+SB). ZnO microparticles of 10 wt. % or 2 wt. % ZnCl 2 was added into SB, resulting in the following groups: PA+SB, PA+SB-ZnO, PA+SB-ZnCl 2 , EDTA+SB, EDTA+SB-ZnO, EDTA+SB-ZnCl 2 . Bonded interfaces were stored for 24 h, and tested or submitted to mechanical loading. Microtensile bond strength was assessed. Debonded surfaces were evaluated by scanning electron microscopy and elemental analysis. The hybrid layer, bottom of the hybrid layer, and peritubular and intertubular dentin were evaluated using a nanoindenter. The load/displacement responses were used for the nanodynamic mechanical analysis III to estimate complex modulus, tan delta, loss modulus, and storage modulus. The modulus mapping was obtained by imposing a quasistatic force setpoint to which a sinusoidal force was superimposed. Atomic force microscopy imaging was performed. Load cycling decreased the tan delta at the PA+SB-ZnCl 2 and EDTA+SB-ZnO interfaces. Tan delta was also diminished at peritubular dentin when PA+SB-ZnO was used, hindering the dissipation of energy throughout these structures. Tan delta increased at the interface after using EDTA+SB-ZnCl 2 , lowering the energy for recoil or failure. After load cycling, loss moduli at the interface decreased when using ZnCl 2 as doping agent, increasing the risk of fracture; but when using ZnO, loss moduli was dissimilarly affected if dentin was EDTA-treated. The border between intertubular and peritubular dentin attained the highest discrepancy in values of viscoelastic properties, meaning a risk for cracking and breakdown of the resin-dentin interface. PA used on dentin provoked differences in complex and storage modulus values at the intertubular and peritubular structures, and these differences were higher than when EDTA was employed. In these cases, the long-term performance of the restorative interface will be impaired.

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

PubMed

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

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. 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. 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). A real-world inspired online course, based on cognitive and motivational conceptual frameworks, seems to be a strong tool to engage students in learning. It may support them to manage the cognitive challenges involved in clinical care and increase their motivation for learning.

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 learning. It may support them to manage the cognitive challenges involved in clinical care and increase their motivation for learning. PMID:27031859

Influence of controlled immediate loading and implant design on peri-implant bone formation.

PubMed

Vandamme, Katleen; Naert, Ignace; Geris, Liesbet; Vander Sloten, Jozef; Puers, Robert; Duyck, Joke

2007-02-01

Tissue formation at the implant interface is known to be sensitive to mechanical stimuli. The aim of the study was to compare the bone formation around immediately loaded versus unloaded implants in two different implant macro-designs. A repeated sampling bone chamber with a central implant was installed in the tibia of 10 rabbits. Highly controlled loading experiments were designed for a cylindrical (CL) and screw-shaped (SL) implant, while the unloaded screw-shaped (SU) implant served as a control. An F-statistic model with alpha=5% determined statistical significance. A significantly higher bone area fraction was observed for SL compared with SU (p<0.0001). The mineralized bone fraction was the highest for SL and significantly different from SU (p<0.0001). The chance that osteoid- and bone-to-implant contact occurred was the highest for SL and significantly different from SU (p<0.0001), but not from CL. When bone-to-implant contact was observed, a loading (SL versus SU: p=0.0049) as well as an implant geometry effect (SL versus CL: p=0.01) was found, in favour of the SL condition. Well-controlled immediate implant loading accelerates tissue mineralization at the interface. Adequate bone stimulation via mechanical coupling may account for the larger bone response around the screw-type implant compared with the cylindrical implant.

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.

The Impact of Clickers Instruction on Cognitive Loads and Listening and Speaking Skills in College English Class

PubMed Central

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. PMID:25192424

Incidental regulation of attraction: The neural basis of the derogation of attractive alternatives in romantic relationships

PubMed Central

Meyer, Meghan L.; Berkman, Elliot T.; Karremans, Johan C.; Lieberman, Matthew D.

2011-01-01

Although a great deal of research addresses the neural basis of deliberate and intentional emotion-regulation strategies, less attention has been paid to the neural mechanisms involved in implicit forms of emotion regulation. Behavioural research suggests that romantically involved participants implicitly derogate the attractiveness of alternative partners, and the present study sought to examine the neural basis of this effect. Romantically committed participants in the present study were scanned with functional magnetic resonance imaging (fMRI) while indicating whether they would consider each of a series of attractive (or unattractive) opposite-sex others as a hypothetical dating partner both while under cognitive load and no cognitive load. Successful derogation of attractive others during the no cognitive load compared to the cognitive load trials corresponded with increased activation in the ventrolateral prefrontal cortex (VLPFC) and posterior dorsomedial prefrontal cortex (pDMPFC), and decreased activation in the ventral striatum, a pattern similar to those reported in deliberate emotion-regulation studies. Activation in the VLPFC and pDMPFC was not significant in the cognitive load condition, indicating that while the derogation effect may be implicit, it nonetheless requires cognitive resources. Additionally, activation in the right VLPFC correlated with participants’ level of relationship investment. These findings suggest that the RVLPFC may play a particularly important role in implicitly regulating the emotions that threaten the stability of a romantic relationship. PMID:21432689

Mild cognitive impairment and asymptomatic Alzheimer disease subjects: equivalent β-amyloid and tau loads with divergent cognitive outcomes.

PubMed

Iacono, Diego; Resnick, Susan M; O'Brien, Richard; Zonderman, Alan B; An, Yang; Pletnikova, Olga; Rudow, Gay; Crain, Barbara; Troncoso, Juan C

2014-04-01

Older adults with intact cognition before death and substantial Alzheimer disease (AD) lesions at autopsy have been termed "asymptomatic AD subjects" (ASYMAD). We previously reported hypertrophy of neuronal cell bodies, nuclei, and nucleoli in the CA1 of the hippocampus (CA1), anterior cingulate gyrus, posterior cingulate gyrus, and primary visual cortex of ASYMAD versus age-matched Control and mild cognitive impairment (MCI) subjects. However, it was unclear whether the neuronal hypertrophy could be attributed to differences in the severity of AD pathology. Here, we performed quantitative analyses of the severity of β-amyloid (Aβ) and phosphorylated tau (tau) loads in the brains of ASYMAD, Control, MCI, and AD subjects (n = 15 per group) from the Baltimore Longitudinal Study of Aging. Tissue sections from CA1, anterior cingulate gyrus, posterior cingulate gyrus, and primary visual cortex were immunostained for Aβ and tau; the respective loads were assessed using unbiased stereology by measuring the fractional areas of immunoreactivity for each protein in each region. The ASYMAD and MCI groups did not differ in Aβ and tau loads. These data confirm that ASYMAD and MCI subjects have comparable loads of insoluble Aβ and tau in regions vulnerable to AD pathology despite divergent cognitive outcomes. These findings imply that cognitive impairment in AD may be caused or modulated by factors other than insoluble forms of Aβ and tau.

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…

Embedded interruptions and task complexity influence schema-related cognitive load progression in an abstract learning task.

PubMed

Wirzberger, Maria; Esmaeili Bijarsari, Shirin; Rey, Günter Daniel

2017-09-01

Cognitive processes related to schema acquisition comprise an essential source of demands in learning situations. Since the related amount of cognitive load is supposed to change over time, plausible temporal models of load progression based on different theoretical backgrounds are inspected in this study. A total of 116 student participants completed a basal symbol sequence learning task, which provided insights into underlying cognitive dynamics. Two levels of task complexity were determined by the amount of elements within the symbol sequence. In addition, interruptions due to an embedded secondary task occurred at five predefined stages over the task. Within the resulting 2x5-factorial mixed between-within design, the continuous monitoring of efficiency in learning performance enabled assumptions on relevant resource investment. From the obtained results, a nonlinear change of learning efficiency over time seems most plausible in terms of cognitive load progression. Moreover, different effects of the induced interruptions show up in conditions of task complexity, which indicate the activation of distinct cognitive mechanisms related to structural aspects of the task. Findings are discussed in the light of evidence from research on memory and information processing. Copyright © 2017 Elsevier B.V. All rights reserved.

Oculomotor capture during real-world scene viewing depends on cognitive load.

PubMed

Matsukura, Michi; Brockmole, James R; Boot, Walter R; Henderson, John M

2011-03-25

It has been claimed that gaze control during scene viewing is largely governed by stimulus-driven, bottom-up selection mechanisms. Recent research, however, has strongly suggested that observers' top-down control plays a dominant role in attentional prioritization in scenes. A notable exception to this strong top-down control is oculomotor capture, where visual transients in a scene draw the eyes. One way to test whether oculomotor capture during scene viewing is independent of an observer's top-down goal setting is to reduce observers' cognitive resource availability. In the present study, we examined whether increasing observers' cognitive load influences the frequency and speed of oculomotor capture during scene viewing. In Experiment 1, we tested whether increasing observers' cognitive load modulates the degree of oculomotor capture by a new object suddenly appeared in a scene. Similarly, in Experiment 2, we tested whether increasing observers' cognitive load modulates the degree of oculomotor capture by an object's color change. In both experiments, the degree of oculomotor capture decreased as observers' cognitive resources were reduced. These results suggest that oculomotor capture during scene viewing is dependent on observers' top-down selection mechanisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Visual-spatial processing and working-memory load as a function of negative and positive psychotic-like experiences.

PubMed

Abu-Akel, A; Reniers, R L E P; Wood, S J

2016-09-01

Patients with schizophrenia show impairments in working-memory and visual-spatial processing, but little is known about the dynamic interplay between the two. To provide insight into this important question, we examined the effect of positive and negative symptom expressions in healthy adults on perceptual processing while concurrently performing a working-memory task that requires the allocations of various degrees of cognitive resources. The effect of positive and negative symptom expressions in healthy adults (N = 91) on perceptual processing was examined in a dual-task paradigm of visual-spatial working memory (VSWM) under three conditions of cognitive load: a baseline condition (with no concurrent working-memory demand), a low VSWM load condition, and a high VSWM load condition. Participants overall performed more efficiently (i.e., faster) with increasing cognitive load. This facilitation in performance was unrelated to symptom expressions. However, participants with high-negative, low-positive symptom expressions were less accurate in the low VSWM condition compared to the baseline and the high VSWM load conditions. Attenuated, subclinical expressions of psychosis affect cognitive performance that is impaired in schizophrenia. The "resource limitations hypothesis" may explain the performance of the participants with high-negative symptom expressions. The dual-task of visual-spatial processing and working memory may be beneficial to assessing the cognitive phenotype of individuals with high risk for schizophrenia spectrum disorders.

Lose-Shift Responding in Humans Is Promoted by Increased Cognitive Load

PubMed Central

Ivan, Victorita E.; Banks, Parker J.; Goodfellow, Kris; Gruber, Aaron J.

2018-01-01

The propensity of animals to shift choices immediately after unexpectedly poor reinforcement outcomes is a pervasive strategy across species and tasks. We report here on the memory supporting such lose-shift responding in humans, assessed using a binary choice task in which random responding is the optimal strategy. Participants exhibited little lose-shift responding when fully attending to the task, but this increased by 30%–40% in participants that performed with additional cognitive load that is known to tax executive systems. Lose-shift responding in the cognitively loaded adults persisted throughout the testing session, despite being a sub-optimal strategy, but was less likely as the time increased between reinforcement and the subsequent choice. Furthermore, children (5–9 years old) without load performed similarly to the cognitively loaded adults. This effect disappeared in older children aged 11–13 years old. These data provide evidence supporting our hypothesis that lose-shift responding is a default and reflexive strategy in the mammalian brain, likely mediated by a decaying memory trace, and is normally suppressed by executive systems. Reducing the efficacy of executive control by cognitive load (adults) or underdevelopment (children) increases its prevalence. It may therefore be an important component to consider when interpreting choice data, and may serve as an objective behavioral assay of executive function in humans that is easy to measure. PMID:29568264

BowMapCL: Burrows-Wheeler Mapping on Multiple Heterogeneous Accelerators.

PubMed

Nogueira, David; Tomas, Pedro; Roma, Nuno

2016-01-01

The computational demand of exact-search procedures has pressed the exploitation of parallel processing accelerators to reduce the execution time of many applications. However, this often imposes strict restrictions in terms of the problem size and implementation efforts, mainly due to their possibly distinct architectures. To circumvent this limitation, a new exact-search alignment tool (BowMapCL) based on the Burrows-Wheeler Transform and FM-Index is presented. Contrasting to other alternatives, BowMapCL is based on a unified implementation using OpenCL, allowing the exploitation of multiple and possibly different devices (e.g., NVIDIA, AMD/ATI, and Intel GPUs/APUs). Furthermore, to efficiently exploit such heterogeneous architectures, BowMapCL incorporates several techniques to promote its performance and scalability, including multiple buffering, work-queue task-distribution, and dynamic load-balancing, together with index partitioning, bit-encoding, and sampling. When compared with state-of-the-art tools, the attained results showed that BowMapCL (using a single GPU) is 2 × to 7.5 × faster than mainstream multi-threaded CPU BWT-based aligners, like Bowtie, BWA, and SOAP2; and up to 4 × faster than the best performing state-of-the-art GPU implementations (namely, SOAP3 and HPG-BWT). When multiple and completely distinct devices are considered, BowMapCL efficiently scales the offered throughput, ensuring a convenient load-balance of the involved processing in the several distinct devices.

Students' Responses to CL-Based Teaching of English Prepositions

ERIC Educational Resources Information Center

Hung, Bui Phu; Truong, Vien; Nguyen, Ngoc Vu

2018-01-01

Purpose: Most EFL textbooks suggest the use of vivid pictures and verbal explanations in teaching English prepositions. However, this word class appears in collocations, and rote-learning does not really help learners retain and use this word class successfully. Cognitive linguistics (CL) has implications for English language teaching as it rests…

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

DTIC Science & Technology

2014-03-01

using scales like NASA’s Task Load Index ( TLX ) (Hart and Staveland, 1988). At present, there are no comparable measurement scales for cognitive...Staveland, L. E. Development of NASA- TLX (Task Load Index): Results of empirical and theoretical research. In Human Mental Workload; Hancock, P. A...Requests for Information SA situation awareness TLX Task Load Index TOC tactical operations center WSMR White Sands Missile Range XO executive

Predicting Risk of Cognitive Decline in Very Old Adults Using Three Models: The Framingham Stroke Risk Profile; the Cardiovascular Risk Factors, Aging, and Dementia Model; and Oxi-Inflammatory Biomarkers.

PubMed

Harrison, Stephanie L; de Craen, Anton J M; Kerse, Ngaire; Teh, Ruth; Granic, Antoneta; Davies, Karen; Wesnes, Keith A; den Elzen, Wendy P J; Gussekloo, Jacobijn; Kirkwood, Thomas B L; Robinson, Louise; Jagger, Carol; Siervo, Mario; Stephan, Blossom C M

2017-02-01

To examine the Framingham Stroke Risk Profile (FSRP); the Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE) risk score, and oxi-inflammatory load (cumulative risk score of three blood biomarkers-homocysteine, interleukin-6, C-reactive protein) for associations with cognitive decline using three cohort studies of very old adults and to examine whether incorporating these biomarkers with the risk scores can affect the association with cognitive decline. Three longitudinal, population-based cohort studies. Newcastle-upon-Tyne, United Kingdom; Leiden, the Netherlands; and Lakes and Bay of Plenty District Health Board areas, New Zealand. Newcastle 85+ Study participants (n = 616), Leiden 85-plus Study participants (n = 444), and Life and Living in Advanced Age, a Cohort Study in New Zealand (LiLACS NZ Study) participants (n = 396). FSRP, CAIDE risk score, oxi-inflammatory load, FSRP incorporating oxi-inflammatory load, and CAIDE risk score incorporating oxi-inflammatory load. Oxi-inflammatory load could be calculated only in the Newcastle 85+ and the Leiden 85-plus studies. Measures of global cognitive function were available for all three data sets. Domain-specific measures were available for the Newcastle 85+ and the Leiden 85-plus studies. Meta-analysis of pooled results showed greater risk of incident global cognitive impairment with higher FSRP (hazard ratio (HR) = 1.46, 95% confidence interval (CI) = 1.08-1.98), CAIDE (HR = 1.53, 95% CI = 1.09-2.14), and oxi-inflammatory load (HR = 1.73, 95% CI = 1.04-2.88) scores. Adding oxi-inflammatory load to the risk scores increased the risk of cognitive impairment for the FSRP (HR = 1.65, 95% CI = 1.17-2.33) and the CAIDE model (HR = 1.93, 95% CI = 1.39-2.67). Adding oxi-inflammatory load to cardiovascular risk scores may be useful for determining risk of cognitive impairment in very old adults. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Cognitive impairment, clinical severity and MRI changes in MELAS syndrome.

PubMed

Kraya, Torsten; Neumann, Lena; Paelecke-Habermann, Yvonne; Deschauer, Marcus; Stoevesandt, Dietrich; Zierz, Stephan; Watzke, Stefan

2017-12-29

To examine clinical severity, cognitive impairment, and MRI changes in patients with MELAS syndrome. Cognitive-mnestic functions, brain MRI (lesion load, cella media index) and clinical severity of ten patients with MELAS syndrome were examined. All patients carried the m.3243A>G mutation. The detailed neuropsychological assessment revealed cognitive deficits in attention, executive function, visuoperception, and -construction. There were significant correlations between these cognitive changes, lesion load in MRI, disturbances in everyday life (clinical scale), and high scores in NMDAS. Patients with MELAS syndrome showed no global neuropsychological deficit, but rather distinct cognitive deficits. Copyright © 2018 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

A study of cognitive loading in dual-coding theory.

PubMed

Ishi, H; Yamauchi, H

1994-08-01

15 university students were engaged in a task of recalling sentences with and without figures. Analysis of the number recalled indicated that cognitive loading for sentences with figures was more effective than for recall of sentences without figures.

A Novel Cognitive Stress Test for the Detection of Preclinical Alzheimer Disease: Discriminative Properties and Relation to Amyloid Load.

PubMed

Loewenstein, David A; Curiel, Rosie E; Greig, Maria T; Bauer, Russell M; Rosado, Marian; Bowers, Dawn; Wicklund, Meredith; Crocco, Elizabeth; Pontecorvo, Michael; Joshi, Abhinay D; Rodriguez, Rosemarie; Barker, Warren W; Hidalgo, Jacqueline; Duara, Ranjan

2016-10-01

To examine the utility of a novel "cognitive stress test" to detect subtle cognitive impairments and amyloid load within the brains of neuropsychologically normal community-dwelling elders. Participants diagnosed as cognitively normal (CN), subjective memory impairment (SMI), mild cognitive impairment (MCI), and preclinical mild cognitive impairment (PreMCI) were administered the Loewenstein-Acevedo Scale for Semantic Interference and Learning (LASSI-L), a sensitive test of proactive semantic interference (PSI), retroactive semantic interference, and, uniquely, the ability to recover from the effects of PSI. Ninety-three subjects (31 men and 62 women) were recruited from three academic institutions in a research consortium. A subset of these individuals underwent 18F florbetapir positron emission tomography scanning. Relative percentages of impairment for each diagnostic group on the LASSI-L were calculated by χ(2) and Fisher's exact tests. Spearman's rho was used to examine associations between amyloid load and different cognitive measures. LASSI-L deficits were identified among 89% of those with MCI, 47% with PreMCI, 33% with SMI, and 13% classified as CN. CN subjects had no difficulties with recovery from PSI, whereas SMI, preMCI, and MCI participants evidenced deficits in recovery from PSI effects. Among a subgroup of participants with normal scores on traditional neuropsychological tests, the strong associations were between the failure to recover from the effects of PSI and amyloid load in the brain. Failure to recover or compensate for the effects of PSI on the LASSI-L distinguishes the LASSI-L from other widely used neuropsychological tests and appears to be sensitive to subtle cognitive impairments and increasing amyloid load. Copyright © 2016 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Reduced but broader prefrontal activity in patients with schizophrenia during n-back working memory tasks: a multi-channel near-infrared spectroscopy study.

PubMed

Koike, Shinsuke; Takizawa, Ryu; Nishimura, Yukika; Kinou, Masaru; Kawasaki, Shingo; Kasai, Kiyoto

2013-09-01

Caudal regions of the prefrontal cortex, including the dorsolateral (DLPFC) and ventrolateral (VLPFC) prefrontal cortex, are involved in essential cognitive functions such as working memory. In contrast, more rostral regions, such as the frontopolar cortex (FpC), have integrative functions among cognitive functions and thereby contribute crucially to real-world social activity. Previous functional magnetic resonance imaging studies have shown patients with schizophrenia had different DLPFC activity pattern in response to cognitive load changes compared to healthy controls; however, the spatial relationship between the caudal and rostral prefrontal activation has not been evaluated under less-constrained conditions. Twenty-six patients with schizophrenia and 26 age-, sex-, and premorbid-intelligence-matched healthy controls participated in this study. Hemodynamic changes during n-back working memory tasks with different cognitive loads were measured using multi-channel near-infrared spectroscopy (NIRS). Healthy controls showed significant task-related activity in the bilateral VLPFC and significant task-related decreased activity in the DLPFC, with greater signal changes when the task required more cognitive load. In contrast, patients with schizophrenia showed activation in the more rostral regions, including bilateral DLPFC and FpC. Neither decreased activity nor greater activation in proportion to elevated cognitive load occurred. This multi-channel NIRS study demonstrated that activation intensity did not increase in patients with schizophrenia associated with cognitive load changes, suggesting hypo-frontality as cognitive impairment in schizophrenia. On the other hand, patients had broader prefrontal activity in areas such as the bilateral DLPFC and FpC regions, thus suggesting a hyper-frontality compensatory response. Copyright © 2013 Elsevier Ltd. All rights reserved.

Use of dissolved chloride concentrations in tributary streams to support geospatial estimates of Cl contamination potential near Skiatook Lake, northeastern Oklahoma

USGS Publications Warehouse

Rice, C.A.; Abbott, M.M.; Zielinski, R.A.

2007-01-01

Releases of NaCl-rich (>100 000 mg/L) water that is co-produced from petroleum wells can adversely affect the quality of ground and surface waters. To evaluate produced water impacts on lakes, rivers and streams, an assessment of the contamination potential must be attainable using reliable and cost-effective methods. This study examines the feasibility of using geographic information system (GIS) analysis to assess the contamination potential of Cl to Skiatook Lake in the Hominy Creek drainage basin in northeastern Oklahoma. GIS-based predictions of affects of Cl within individual subdrainages are supported by measurements of Cl concentration and discharge in 19 tributaries to Skiatook Lake. Dissolved Cl concentrations measured in October, 2004 provide a snapshot of conditions assumed to be reasonably representative of typical inputs to the lake. Chloride concentrations ranged from 5.8 to 2300 mg/L and compare to a value of 34 mg/L in the lake. At the time of sampling, Hominy Creek provided 63% of the surface water entering the lake and 80% of the Cl load. The Cl load from the other tributaries is relatively small (150 mg/L) were generally in subdrainages with greater well density (>15 wells/km2), relatively large numbers of petroleum wells in close proximity (>2 proximity wells/stream km), and relatively small discharge (<0.005 m3/s). GIS calculations of subdrainage areas can be used to estimate the expected discharge of the tributary for each subdrainage. GIS-based assessment of Cl contamination potential at Skiatook Lake and at other lakes surrounded by oil fields can proceed even when direct measurements of Cl or discharge in tributary streams may be limited or absent.

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. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Controlled Release of Antimicrobial ClO2 Gas from a Two-Layer Polymeric Film System.

PubMed

Bai, Zhifeng; Cristancho, Diego E; Rachford, Aaron A; Reder, Amy L; Williamson, Alexander; Grzesiak, Adam L

2016-11-16

We report a two-component label system comprising a chlorite-containing polymer film and an acid-containing polymer film that can release antimicrobial ClO 2 gas upon adhering the two films together to enable a reaction of the chlorite and acid under moisture exposure. The chlorite-containing film comprises a commercial acrylate-based pressure-sensitive adhesive polymer impregnated with sodium chlorite. The acid-containing film comprises a commercial poly(vinyl alcohol) polymer loaded with tartaric acid. Both of the films were prepared on low ClO 2 -absorbing substrate films from stable aqueous systems of the polymers with high reagent loading. Rapid and sustained releases of significant amounts of ClO 2 gas from the label system were observed in an in situ quantification system using UV-vis spectroscopy. It was found that the ClO 2 release is slower at a lower temperature and can be accelerated by moisture in the atmosphere and the films. Controlled release of ClO 2 gas from the label system was demonstrated by tailoring film composition and thickness. A model was developed to extract release kinetics and revealed good conversions of the label system. This two-component system can potentially be applied as a two-part label without premature release for applications in food packaging.

Combination of PPT with LiCl Treatment Prevented Bilateral Ovariectomy-Induced Hippocampal-Dependent Cognition Deficit in Rats.

PubMed

Qu, Na; Zhou, Xiang-Yu; Han, Li; Wang, Lei; Xu, Jia-Xin; Zhang, Teng; Chu, Jiang; Chen, Qiao; Wang, Jian-Zhi; Zhang, Qi; Tian, Qing

2016-03-01

Estrogen deprivation is a high risk of cognitive dysfunction in neurodegenerative diseases, and the early used estrogen replacement has been proved effective in many studies. Because of the adverse actions, selective estrogen receptor modulating has been raised to substitute for estrogen replacement. In this study, we observed in hippocampus of bilaterally ovariectomized rats that the level of estrogen receptor α (ERα) was decreased in nuclei with activated glycogen synthase kinase-3β (GSK-3β) in cytoplasm at 8 weeks after operation. The level of nuclear ERα is important for its transcriptional property, and the inhibition of GSK-3β benefits to ERα nuclear translocation. Then, we used 4,4k,4a-(4-propyl-[1H]-pyrazole-1, 3, 5-triyl) trisphenol (PPT) (1 mg/kg/day), an agonist of ERα, combined with LiCl (40 mg/kg/day), an inhibitor of GSK-3β, to treat the ovariectomized rats. After the combination treatment of these two drugs (PPT + LiCl), the improved learning and memory abilities of ovariectomized rats in Morris water maze, increased dendritic spines in CA1 region, and decreased tau phosphorylation at Ser-396 in hippocampus were observed. Furthermore, PPT + LiCl treatment significantly increased ERα level in the nuclear fraction of hippocampus, and in the cytoplasmic fraction, the total level of GSK-3β was declined after treatment with its increased phosphorylation at Ser-9 (inactivation form). This study suggested that PPT + LiCl treatment could inhibit the activation of cytoplasmic GSK-3β and promote the nuclear translocation of ERα, and ERα together with GSK-3β maybe the targets to preserve hippocampus-dependent cognitive ability after long-term ovariectomy.

Potential Interactions of Calcium-Sensitive Reagents with Zinc Ion in Different Cultured Cells

PubMed Central

Fujikawa, Koichi; Fukumori, Ryo; Nakamura, Saki; Kutsukake, Takaya; Takarada, Takeshi; Yoneda, Yukio

2015-01-01

Background Several chemicals have been widely used to evaluate the involvement of free Ca2+ in mechanisms underlying a variety of biological responses for decades. Here, we report high reactivity to zinc of well-known Ca2+-sensitive reagents in diverse cultured cells. Methodology/Principal Findings In rat astrocytic C6 glioma cells loaded with the fluorescent Ca2+ dye Fluo-3, the addition of ZnCl2 gradually increased the fluorescence intensity in a manner sensitive to the Ca2+ chelator EGTA irrespective of added CaCl2. The addition of the Ca2+ ionophore A23187 drastically increased Fluo-3 fluorescence in the absence of ZnCl2, while the addition of the Zn2+ ionophore pyrithione rapidly and additionally increased the fluorescence in the presence of ZnCl2, but not in its absence. In cells loaded with the zinc dye FluoZin-3 along with Fluo-3, a similarly gradual increase was seen in the fluorescence of Fluo-3, but not of FluoZin-3, in the presence of both CaCl2 and ZnCl2. Further addition of pyrithione drastically increased the fluorescence intensity of both dyes, while the addition of the Zn2+ chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethane-1,2-diamine (TPEN) rapidly and drastically decreased FluoZin-3 fluorescence. In cells loaded with FluoZin-3 alone, the addition of ZnCl2 induced a gradual increase in the fluorescence in a fashion independent of added CaCl2 but sensitive to EGTA. Significant inhibition was found in the vitality to reduce 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide in a manner sensitive to TPEN, EDTA and BAPTA in C6 glioma cells exposed to ZnCl2, with pyrithione accelerating the inhibition. Similar inhibition occurred in an EGTA-sensitive fashion after brief exposure to ZnCl2 in pluripotent P19 cells, neuronal Neuro2A cells and microglial BV2 cells, which all expressed mRNA for particular zinc transporters. Conclusions/Significance Taken together, comprehensive analysis is absolutely required for the demonstration of a variety of physiological and pathological responses mediated by Ca2+ in diverse cells enriched of Zn2+. PMID:26010609

An analysis of the suitability of a low-cost eye tracker for assessing the cognitive load of drivers.

PubMed

Čegovnik, Tomaž; Stojmenova, Kristina; Jakus, Grega; Sodnik, Jaka

2018-04-01

This paper presents a driving simulator study in which we investigated whether the Eye Tribe eye tracker (ET) is capable of assessing changes in the cognitive load of drivers through oculography and pupillometry. In the study, participants were asked to drive a simulated vehicle and simultaneously perform a set of secondary tasks with different cognitive complexity levels. We measured changes in eye properties, such as the pupil size, blink rate and fixation time. We also performed a measurement with a Detection Response Task (DRT) to validate the results and to prove a steady increase of cognitive load with increasing secondary task difficulty. The results showed that the ET precisely recognizes an increasing pupil diameter with increasing secondary task difficulty. In addition, the ET shows increasing blink rates, decreasing fixation time and narrowing of the attention field with increasing secondary task difficulty. The results were validated with the DRT method and the secondary task performance. We conclude that the Eye Tribe ET is a suitable device for assessing a driver's cognitive load. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of cognitive load on speech prosody in aviation: Evidence from military simulator flights.

PubMed

Huttunen, Kerttu; Keränen, Heikki; Väyrynen, Eero; Pääkkönen, Rauno; Leino, Tuomo

2011-01-01

Mental overload directly affects safety in aviation and needs to be alleviated. Speech recordings are obtained non-invasively and as such are feasible for monitoring cognitive load. We recorded speech of 13 military pilots while they were performing a simulator task. Three types of cognitive load (load on situation awareness, information processing and decision making) were rated by a flight instructor separately for each flight phase and participant. As a function of increased cognitive load, the mean utterance-level fundamental frequency (F0) increased, on average, by 7 Hz and the mean vocal intensity increased by 1 dB. In the most intensive simulator flight phases, mean F0 increased by 12 Hz and mean intensity, by 1.5 dB. At the same time, the mean F0 range decreased by 5 Hz, on average. Our results showed that prosodic features of speech can be used to monitor speaker state and support pilot training in a simulator environment. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Cognitive load of navigating without vision when guided by virtual sound versus spatial language.

PubMed

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

2006-12-01

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") or virtual sound (i.e., the perceived azimuth of the sound indicated the target direction). The authors hypothesized that virtual sound, being processed at direct perceptual levels, would have lower load than even simple language commands, which require cognitive mediation. As predicted, whereas the guidance modes did not differ significantly in the no-load condition, participants showed shorter distance traveled and less time to complete a path when performing the N-back task while navigating with virtual sound as guidance. Virtual sound also produced better N-back performance than spatial language. By indicating the superiority of virtual sound for guidance when cognitive load is present, as is characteristic of everyday navigation, these results have implications for guidance systems for the visually impaired and others.

Effect of meal volume and calorie load on postprandial gastric function and emptying: studies under physiological conditions by combined fiber-optic pressure measurement and MRI.

PubMed

Kwiatek, Monika A; Menne, Dieter; Steingoetter, Andreas; Goetze, Oliver; Forras-Kaufman, Zsofia; Kaufman, Elad; Fruehauf, Heiko; Boesiger, Peter; Fried, Michael; Schwizer, Werner; Fox, Mark R

2009-11-01

This study assessed the effects of meal volume (MV) and calorie load (CL) on gastric function. MRI and a minimally invasive fiber-optic recording system (FORS) provided simultaneous measurement of gastric volume and pressure changes during gastric filling and emptying of a liquid nutrient meal in physiological conditions. The gastric response to 12 iso-osmolar MV-CL combinations of a multinutrient drink (MV: 200, 400, 600, 800 ml; CL: 200, 300, 400 kcal) was tested in 16 healthy subjects according to a factorial design. Total gastric volume (TGV) and gastric content volume (GCV = MV + secretion) were measured by MRI during nasogastric meal infusion and gastric emptying over 60 min. Intragastric pressure was assessed at 1 Hz by FORS. The dynamic change in postprandial gastric volumes was described by a validated three-component linear exponential model. The stomach expanded with MV, but the ratio of GCV:MV at t(0) diminished with increasing MV (P < 0.01). Postprandial changes in TGV followed those of GCV. Intragastric pressure increased with MV, and this effect was augmented further by CL (P = 0.02); however, the absolute pressure rise was <4 mmHg. A further postprandial increase of gastric volumes was observed early on before any subsequent volume decrease. This "early" increase in GCV was greater for smaller than larger MV (P < 0.01), indicating faster initial gastric emptying of larger MV. In contrast, volume change during filling and in the early postprandial period were unaffected by CL. In the later postprandial period, gastric emptying rate continued to be more rapid with high MVs (P < 0.001); however, at any given volume, gastric emptying was slowed by higher CL (P < 0.001). GCV half-emptying time decreased with CL at 18 +/- 6 min for each additional 100-kcal load (P < 0.001). These findings indicate that gastric wall stress (passive strain and active tone) provides the driving force for gastric emptying, but distal resistance to gastric outflow regulates further passage of nutrients. The distinct early phase of gastric emptying with relatively rapid, uncontrolled passage of nutrients into the small bowel, modulated by meal volume but not nutrient composition, ensures that the delivery of nutrients in the later postprandial period is related to the overall calorie load of the meal.

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:…

Effects of Load, Cognitive Complexity and Type A on Satisfaction.

DTIC Science & Technology

1983-06-01

load, performance , style, cognitive style, Type A, cognitive complexity, stress, satisfaction , visual motor tasks 20. ABSTRAC (Continue on reverse side...1982) and Ewen (1973) have pointed toward pressure to perform as a condition which modifies the satisfaction - performance relationship. Other moderator...1975; Mehrabian and West, 1977) are much more rare than theory and research focused on, for example, the performance - satisfaction relationship

Effect of perceptual load on conceptual processing: an extension of Vermeulen's theory.

PubMed

Xie, Jiushu; Wang, Ruiming; Sun, Xun; Chang, Song

2013-10-01

The effect of color and shape load on conceptual processing was studied. Perceptual load effects have been found in visual and auditory conceptual processing, supporting the theory of embodied cognition. However, whether different types of visual concepts, such as color and shape, share the same perceptual load effects is unknown. In the current experiment, 32 participants were administered simultaneous perceptual and conceptual tasks to assess the relation between perceptual load and conceptual processing. Keeping color load in mind obstructed color conceptual processing. Hence, perceptual processing and conceptual load shared the same resources, suggesting embodied cognition. Color conceptual processing was not affected by shape pictures, indicating that different types of properties within vision were separate.

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

DOEpatents

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.

The effect of cognitive load on hemispheric asymmetries in true and false memory.

PubMed

Tat, Michael J; Azuma, Tamiko

2016-01-01

Studies examining hemispheric asymmetries in false memory have shown that the right hemisphere (RH) is more susceptible to false memories compared to the left hemisphere (LH). Theories suggest that hemispheric asymmetries in true and false memory may be due to differences in representational coding and the use of top-down mechanisms in each hemisphere. In the current study, the Deese-Roediger-McDermott false memory paradigm was used in conjunction with divided visual field presentation to examine the role of top-down mechanisms in hemispheric asymmetries of true and false memory. In Experiment 1, participants studied lists of related words while completing secondary cognitive load tasks. In Experiment 2, the secondary tasks were administered during memory retrieval instead of memory encoding. Results revealed that cognitive loads imposed during the study phase influenced veridical memory in the LH more than the RH, but cognitive loads imposed during retrieval did not influence veridical memory in either hemisphere. Surprisingly, false memory rates were not influenced by cognitive loads and were higher in the LH. These data provide evidence that, at least for veridical memory, top-down control mechanisms are used more readily for the encoding of information into memory in the LH compared to the RH.

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. Copyright © 2015 Elsevier B.V. All rights reserved.

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

Faded-example as a Tool to Acquire and Automate Mathematics Knowledge

NASA Astrophysics Data System (ADS)

Retnowati, E.

2017-04-01

Students themselves accomplish Knowledge acquisition and automation. The teacher plays a role as the facilitator by creating mathematics tasks that assist students in building knowledge efficiently and effectively. Cognitive load caused by learning material presented by teachers should be considered as a critical factor. While the intrinsic cognitive load is related to the degree of complexity of the material learning ones can handle, the extraneous cognitive load is directly caused by how the material is presented. Strategies to present a learning material in computational learning domains like mathematics are a namely worked example (fully-guided task) or problem-solving (discovery task with no guidance). According to the empirical evidence, learning based on problem-solving may cause high-extraneous cognitive load for students who have limited prior knowledge, conversely learn based on worked example may cause high-extraneous cognitive load for students who have mastered the knowledge base. An alternative is a faded example consisting of the partly-completed task. Learning from faded-example can facilitate students who already acquire some knowledge about the to-be-learned material but still need more practice to automate the knowledge further. This instructional strategy provides a smooth transition from a fully-guided into an independent problem solver. Designs of faded examples for learning trigonometry are discussed.

Search, Memory, and Choice Error: An Experiment

PubMed Central

Sanjurjo, Adam

2015-01-01

Multiple attribute search is a central feature of economic life: we consider much more than price when purchasing a home, and more than wage when choosing a job. An experiment is conducted in order to explore the effects of cognitive limitations on choice in these rich settings, in accordance with the predictions of a new model of search memory load. In each task, subjects are made to search the same information in one of two orders, which differ in predicted memory load. Despite standard models of choice treating such variations in order of acquisition as irrelevant, lower predicted memory load search orders are found to lead to substantially fewer choice errors. An implication of the result for search behavior, more generally, is that in order to reduce memory load (thus choice error) a limited memory searcher ought to deviate from the search path of an unlimited memory searcher in predictable ways-a mechanism that can explain the systematic deviations from optimal sequential search that have recently been discovered in peoples' behavior. Further, as cognitive load is induced endogenously (within the task), and found to affect choice behavior, this result contributes to the cognitive load literature (in which load is induced exogenously), as well as the cognitive ability literature (in which cognitive ability is measured in a separate task). In addition, while the information overload literature has focused on the detrimental effects of the quantity of information on choice, this result suggests that, holding quantity constant, the order that information is observed in is an essential determinant of choice failure. PMID:26121356

The influence of cognitive load on transfer with error prevention training methods: a meta-analysis.

PubMed

Hutchins, Shaun D; Wickens, Christopher D; Carolan, Thomas F; Cumming, John M

2013-08-01

The objective was to conduct research synthesis for the U.S.Army on the effectiveness of two error prevention training strategies (training wheels and scaffolding) on the transfer of training. Motivated as part of an ongoing program of research on training effectiveness, the current work presents some of the program's research into the effects on transfer of error prevention strategies during training from a cognitive load perspective. Based on cognitive load theory, two training strategies were hypothesized to reduce intrinsic load by supporting learners early in acquisition during schema development. A transfer ratio and Hedges' g were used in the two meta-analyses conducted on transfer studies employing the two training strategies. Moderators relevant to cognitive load theory and specific to the implemented strategies were examined.The transfer ratio was the ratio of treatment transfer performance to control transfer. Hedges' g was used in comparing treatment and control group standardized mean differences. Both effect sizes were analyzed with versions of sample weighted fixed effect models. Analysis of the training wheels strategy suggests a transfer benefit. The observed benefit was strongest when the training wheels were a worked example coupled with a principle-based prompt. Analysis of the scaffolding data also suggests a transfer benefit for the strategy. Both training wheels and scaffolding demonstrated positive transfer as training strategies.As error prevention techniques, both support the intrinsic load--reducing implications of cognitive load theory. The findings are applicable to the development of instructional design guidelines in professional skill-based organizations such as the military.

Enhanced removal of arsenic from a highly laden industrial effluent using a combined coprecipitation/nano-adsorption process.

PubMed

Jiang, Yingnan; Hua, Ming; Wu, Bian; Ma, Hongrui; Pan, Bingcai; Zhang, Quanxing

2014-05-01

Effective arsenic removal from highly laden industrial wastewater is an important but challenging task. Here, a combined coprecipitation/nano-adsorption process, with ferric chloride and calcium chloride as coprecipitation agents and polymer-based nanocomposite as selective adsorbent, has been validated for arsenic removal from tungsten-smelting wastewater. On the basis of operating optimization, a binary FeCl3 (520 mg/L)-CaCl2 (300 mg/L) coprecipitation agent could remove more than 93% arsenic from the wastewater. The resulting precipitate has proved environmental safety based on leaching toxicity test. Fixed-bed column packed with zirconium or ferric-oxide-loaded nanocomposite was employed for further elimination of arsenic in coprecipitated effluent, resulting in a significant decrease of arsenic (from 0.96 to less than 0.5 mg/L). The working capacity of zirconium-loaded nanocomposite was 220 bed volumes per run, much higher than that of ferric-loaded nanocomposite (40 bed volumes per run). The exhausted zirconium-loaded nanocomposite could be efficiently in situ regenerated with a binary NaOH-NaCl solution for reuse without any significant capacity loss. The results validated the combinational coprecipitation/nano-adsorption process to be a potential alternative for effective arsenic removal from highly laden industrial effluent.

Formulation, Characterization and Stability Assessment of a Food-Derived Tripeptide, Leucine-Lysine-Proline Loaded Chitosan Nanoparticles.

PubMed

Danish, Minna K; Vozza, Giuliana; Byrne, Hugh J; Frias, Jesus M; Ryan, Sinéad M

2017-09-01

The chicken- or fish-derived tripeptide, leucine-lysine-proline (LKP), inhibits the angiotensin converting enzyme and may be used as an alternative treatment for prehypertension. However, it has low permeation across the small intestine. The formulation of LKP into a nanoparticle (NP) has the potential to address this issue. LKP-loaded NPs were produced using an ionotropic gelation technique, using chitosan (CL113). Following optimization of unloaded NPs, a mixture amount design was constructed using variable concentration of CL113 and tripolyphosphate at a fixed LKP concentration. Resultant particle sizes ranged from 120 to 271 nm, zeta potential values from 29 to 37 mV, and polydispersity values from 0.3 to 0.6. A ratio of 6:1 (CL113:TPP) produced the best encapsulation of approximately 65%. Accelerated studies of the loaded NPs indicated stability under normal storage conditions (room temperature). Cytotoxicity assessment showed no significant loss of cell viability and in vitro release studies indicated an initial burst followed by a slower and sustained release. © 2017 Institute of Food Technologists®.

Visual representations in science education: The influence of prior knowledge and cognitive load theory on instructional design principles

NASA Astrophysics Data System (ADS)

Cook, Michelle Patrick

2006-11-01

Visual representations are essential for communicating ideas in the science classroom; however, the design of such representations is not always beneficial for learners. This paper presents instructional design considerations providing empirical evidence and integrating theoretical concepts related to cognitive load. Learners have a limited working memory, and instructional representations should be designed with the goal of reducing unnecessary cognitive load. However, cognitive architecture alone is not the only factor to be considered; individual differences, especially prior knowledge, are critical in determining what impact a visual representation will have on learners' cognitive structures and processes. Prior knowledge can determine the ease with which learners can perceive and interpret visual representations in working memory. Although a long tradition of research has compared experts and novices, more research is necessary to fully explore the expert-novice continuum and maximize the potential of visual representations.

Review of the long-term pavement performance backcalculation results : final report

DOT National Transportation Integrated Search

2006-02-01

A new approach to determine layered elastic moduli from in situ load-deflection data was developed. This forwardcalculation approach differs from backcalculation in that modulus estimates come directly from the load and deflection data using cl...

Acute glycaemic load breakfast manipulations do not attenuate cognitive impairments in adults with type 2 diabetes.

PubMed

Lamport, Daniel Joseph; Dye, Louise; Mansfield, Michael W; Lawton, Clare L

2013-04-01

Research on young healthy samples suggests that low glycaemic load foods can confer benefits for cognitive performance. The aim was to examine the effects of type 2 diabetes on cognitive function, and to investigate whether consumption of low glycaemic load breakfasts affects cognitive function in adults with type 2 diabetes. Memory, psychomotor skill and executive function were examined at two morning test sessions in 24 adults with type 2 diabetes and 10 adults with normal glucose tolerance (NGT) aged 45-77 years without dementia after water, low, and high glycaemic load breakfasts were consumed in accordance with a crossover, counterbalanced design. The type 2 diabetes and NGT groups were matched for education, depression, and IQ. Type 2 diabetes was associated with impairments in verbal memory, spatial memory, psychomotor skill, and executive function compared to adults with NGT. Consumption of the three breakfast conditions did not impact on cognitive performance in the type 2 diabetes or NGT participants. Abnormalities in glucose tolerance such as type 2 diabetes can have demonstrable negative effects on a range of cognitive functions. However, there was no evidence that low GL breakfasts administered acutely could confer benefits for cognitive function (ClincalTrials.gov identifier, NCT01047813). Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Incidental regulation of attraction: the neural basis of the derogation of attractive alternatives in romantic relationships.

PubMed

Meyer, Meghan L; Berkman, Elliot T; Karremans, Johan C; Lieberman, Matthew D

2011-04-01

Although a great deal of research addresses the neural basis of deliberate and intentional emotion-regulation strategies, less attention has been paid to the neural mechanisms involved in implicit forms of emotion regulation. Behavioural research suggests that romantically involved participants implicitly derogate the attractiveness of alternative partners, and the present study sought to examine the neural basis of this effect. Romantically committed participants in the present study were scanned with functional magnetic resonance imaging (fMRI) while indicating whether they would consider each of a series of attractive (or unattractive) opposite-sex others as a hypothetical dating partner both while under cognitive load and no cognitive load. Successful derogation of attractive others during the no cognitive load compared to the cognitive load trials corresponded with increased activation in the ventrolateral prefrontal cortex (VLPFC) and posterior dorsomedial prefrontal cortex (pDMPFC), and decreased activation in the ventral striatum, a pattern similar to those reported in deliberate emotion-regulation studies. Activation in the VLPFC and pDMPFC was not significant in the cognitive load condition, indicating that while the derogation effect may be implicit, it nonetheless requires cognitive resources. Additionally, activation in the right VLPFC correlated with participants' level of relationship investment. These findings suggest that the RVLPFC may play a particularly important role in implicitly regulating the emotions that threaten the stability of a romantic relationship. © 2011 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

The Older Adult Positivity Effect in Evaluations of Trustworthiness: Emotion Regulation or Cognitive Capacity?

PubMed

Zebrowitz, Leslie A; Boshyan, Jasmine; Ward, Noreen; Gutchess, Angela; Hadjikhani, Nouchine

2017-01-01

An older adult positivity effect, i.e., the tendency for older adults to favor positive over negative stimulus information more than do younger adults, has been previously shown in attention, memory, and evaluations. This effect has been attributed to greater emotion regulation in older adults. In the case of attention and memory, this explanation has been supported by some evidence that the older adult positivity effect is most pronounced for negative stimuli, which would motivate emotion regulation, and that it is reduced by cognitive load, which would impede emotion regulation. We investigated whether greater older adult positivity in the case of evaluative responses to faces is also enhanced for negative stimuli and attenuated by cognitive load, as an emotion regulation explanation would predict. In two studies, younger and older adults rated trustworthiness of faces that varied in valence both under low and high cognitive load, with the latter manipulated by a distracting backwards counting task. In Study 1, face valence was manipulated by attractiveness (low /disfigured faces, medium, high/fashion models' faces). In Study 2, face valence was manipulated by trustworthiness (low, medium, high). Both studies revealed a significant older adult positivity effect. However, contrary to an emotion regulation account, this effect was not stronger for more negative faces, and cognitive load increased rather than decreased the rated trustworthiness of negatively valenced faces. Although inconsistent with emotion regulation, the latter effect is consistent with theory and research arguing that more cognitive resources are required to process negative stimuli, because they are more cognitively elaborated than positive ones. The finding that increased age and increased cognitive load both enhanced the positivity of trustworthy ratings suggests that the older adult positivity effect in evaluative ratings of faces may reflect age-related declines in cognitive capacity rather than increases in the regulation of negative emotions.

Amyloid mediates the association of apolipoprotein E e4 allele to cognitive function in older people

PubMed Central

Bennett, D; Schneider, J; Wilson, R; Bienias, J; Berry-Kravis, E; Arnold, S

2005-01-01

Background: The neurobiological changes underlying the association of the apolipoprotein E (APOE) e4 allele with level of cognition are poorly understood. Objective: To test the hypothesis that amyloid load can account for (mediate) the association of the APOE e4 allele with level of cognition assessed proximate to death. Methods: There were 44 subjects with clinically diagnosed Alzheimer's disease and 50 without dementia, who had participated in the Religious Orders Study. They underwent determination of APOE allele status, had comprehensive cognitive testing in the last year of life, and brain autopsy at death. The percentage area of cortex occupied by amyloid beta and the density of tau positive neurofibrillary tangles were quantified from six brain regions and averaged to yield summary measures of amyloid load and neurofibrillary tangles. Multiple regression analyses were used to examine whether amyloid load could account for the effect of allele status on level of cognition, controlling for age, sex, and education. Results: Possession of at least one APOE e4 allele was associated with lower level of cognitive function proximate to death (p = 0.04). The effect of the e4 allele was reduced by nearly 60% and was no longer significant after controlling for the effect of amyloid load, whereas there was a robust inverse association between amyloid and cognition (p = 0.001). Because prior work had suggested that neurofibrillary tangles could account for the association of amyloid on cognition, we next examined whether amyloid could account for the effect of allele status on tangles. In a series of regression analyses, e4 was associated with density of tangles (p = 0.002), but the effect of the e4 allele was reduced by more than 50% and was no longer significant after controlling for the effect of amyloid load. Conclusion: These findings are consistent with a sequence of events whereby the e4 allele works through amyloid deposition and subsequent tangle formation to cause cognitive impairment. PMID:16107349

Learning STEM Through Integrative Visual Representations

NASA Astrophysics Data System (ADS)

Virk, Satyugjit Singh

Previous cognitive models of memory have not comprehensively taken into account the internal cognitive load of chunking isolated information and have emphasized the external cognitive load of visual presentation only. Under the Virk Long Term Working Memory Multimedia Model of cognitive load, drawing from the Cowan model, students presented with integrated animations of the key neural signal transmission subcomponents where the interrelationships between subcomponents are visually and verbally explicit, were hypothesized to perform significantly better on free response and diagram labeling questions, than students presented with isolated animations of these subcomponents. This is because the internal attentional cognitive load of chunking these concepts is greatly reduced and hence the overall cognitive load is less for the integrated visuals group than the isolated group, despite the higher external load for the integrated group of having the interrelationships between subcomponents presented explicitly. Experiment 1 demonstrated that integrating the subcomponents of the neuron significantly enhanced comprehension of the interconnections between cellular subcomponents and approached significance for enhancing comprehension of the layered molecular correlates of the cellular structures and their interconnections. Experiment 2 corrected time on task confounds from Experiment 1 and focused on the cellular subcomponents of the neuron only. Results from the free response essay subcomponent subscores did demonstrate significant differences in favor of the integrated group as well as some evidence from the diagram labeling section. Results from free response, short answer and What-If (problem solving), and diagram labeling detailed interrelationship subscores demonstrated the integrated group did indeed learn the extra material they were presented with. This data demonstrating the integrated group learned the extra material they were presented with provides some initial support for the assertion that chunking mediated the greater gains in learning for the neural subcomponent concepts over the control.

The complex interaction between anxiety and cognition: insight from spatial and verbal working memory

PubMed Central

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. PMID:23542914

Brain beta-amyloid measures and magnetic resonance imaging atrophy both predict time-to-progression from mild cognitive impairment to Alzheimer's disease.

PubMed

Jack, Clifford R; Wiste, Heather J; Vemuri, Prashanthi; Weigand, Stephen D; Senjem, Matthew L; Zeng, Guang; Bernstein, Matt A; Gunter, Jeffrey L; Pankratz, Vernon S; Aisen, Paul S; Weiner, Michael W; Petersen, Ronald C; Shaw, Leslie M; Trojanowski, John Q; Knopman, David S

2010-11-01

Biomarkers of brain Aβ amyloid deposition can be measured either by cerebrospinal fluid Aβ42 or Pittsburgh compound B positron emission tomography imaging. Our objective was to evaluate the ability of Aβ load and neurodegenerative atrophy on magnetic resonance imaging to predict shorter time-to-progression from mild cognitive impairment to Alzheimer's dementia and to characterize the effect of these biomarkers on the risk of progression as they become increasingly abnormal. A total of 218 subjects with mild cognitive impairment were identified from the Alzheimer's Disease Neuroimaging Initiative. The primary outcome was time-to-progression to Alzheimer's dementia. Hippocampal volumes were measured and adjusted for intracranial volume. We used a new method of pooling cerebrospinal fluid Aβ42 and Pittsburgh compound B positron emission tomography measures to produce equivalent measures of brain Aβ load from either source and analysed the results using multiple imputation methods. We performed our analyses in two phases. First, we grouped our subjects into those who were 'amyloid positive' (n = 165, with the assumption that Alzheimer's pathology is dominant in this group) and those who were 'amyloid negative' (n = 53). In the second phase, we included all 218 subjects with mild cognitive impairment to evaluate the biomarkers in a sample that we assumed to contain a full spectrum of expected pathologies. In a Kaplan-Meier analysis, amyloid positive subjects with mild cognitive impairment were much more likely to progress to dementia within 2 years than amyloid negative subjects with mild cognitive impairment (50 versus 19%). Among amyloid positive subjects with mild cognitive impairment only, hippocampal atrophy predicted shorter time-to-progression (P < 0.001) while Aβ load did not (P = 0.44). In contrast, when all 218 subjects with mild cognitive impairment were combined (amyloid positive and negative), hippocampal atrophy and Aβ load predicted shorter time-to-progression with comparable power (hazard ratio for an inter-quartile difference of 2.6 for both); however, the risk profile was linear throughout the range of hippocampal atrophy values but reached a ceiling at higher values of brain Aβ load. Our results are consistent with a model of Alzheimer's disease in which Aβ deposition initiates the pathological cascade but is not the direct cause of cognitive impairment as evidenced by the fact that Aβ load severity is decoupled from risk of progression at high levels. In contrast, hippocampal atrophy indicates how far along the neurodegenerative path one is, and hence how close to progressing to dementia. Possible explanations for our finding that many subjects with mild cognitive impairment have intermediate levels of Aβ load include: (i) individual subjects may reach an Aβ load plateau at varying absolute levels; (ii) some subjects may be more biologically susceptible to Aβ than others; and (iii) subjects with mild cognitive impairment with intermediate levels of Aβ may represent individuals with Alzheimer's disease co-existent with other pathologies.

Prevalence of Dementia and Cognitive Complaints in the Context of High Cognitive Reserve: A Population-Based Study.

PubMed

Perquin, Magali; Diederich, Nico; Pastore, Jessica; Lair, Marie-Lise; Stranges, Saverio; Vaillant, Michel

2015-01-01

This study aimed to assess the prevalence of dementia and cognitive complaints in a cross-sectional sample of Luxembourg seniors, and to discuss the results in the societal context of high cognitive reserve resulting from multilingualism. A population sample of 1,377 people representative of Luxembourg residents aged over 64 years was initially identified via the national social insurance register. There were three different levels of contribution: full participation in the study, partial participation, and non-participation. We examined the profiles of these three different samples so that we could infer the prevalence estimates in the Luxembourgish senior population as a whole using the prevalence estimates obtained in this study. After careful attention to the potential bias and of the possibility of underestimation, we considered the obtained prevalence estimates of 3.8% for dementia (with corresponding 95% confidence limits (CL) of 2.8% and 4.8%) and 26.1% for cognitive complaints (CL = [17.8-34.3]) as trustworthy. Based on these findings, we postulate that high cognitive reserve may result in surprisingly low prevalence estimates of cognitive complaints and dementia in adults over the age of 64 years, which thereby corroborates the longer disability-free life expectancy observed in the Luxembourg population. To the best of our knowledge, this study is the first to report such Luxembourgish public health data.

Prevalence of Dementia and Cognitive Complaints in the Context of High Cognitive Reserve: A Population-Based Study

PubMed Central

Perquin, Magali; Diederich, Nico; Pastore, Jessica; Lair, Marie-Lise; Stranges, Saverio; Vaillant, Michel

2015-01-01

Objectives This study aimed to assess the prevalence of dementia and cognitive complaints in a cross-sectional sample of Luxembourg seniors, and to discuss the results in the societal context of high cognitive reserve resulting from multilingualism. Methods A population sample of 1,377 people representative of Luxembourg residents aged over 64 years was initially identified via the national social insurance register. There were three different levels of contribution: full participation in the study, partial participation, and non-participation. We examined the profiles of these three different samples so that we could infer the prevalence estimates in the Luxembourgish senior population as a whole using the prevalence estimates obtained in this study. Results After careful attention to the potential bias and of the possibility of underestimation, we considered the obtained prevalence estimates of 3.8% for dementia (with corresponding 95% confidence limits (CL) of 2.8% and 4.8%) and 26.1% for cognitive complaints (CL = [17.8–34.3]) as trustworthy. Conclusion Based on these findings, we postulate that high cognitive reserve may result in surprisingly low prevalence estimates of cognitive complaints and dementia in adults over the age of 64 years, which thereby corroborates the longer disability-free life expectancy observed in the Luxembourg population. To the best of our knowledge, this study is the first to report such Luxembourgish public health data. PMID:26390288

Late-onset Alzheimer's risk variants in memory decline, incident mild cognitive impairment, and Alzheimer's disease.

PubMed

Carrasquillo, Minerva M; Crook, Julia E; Pedraza, Otto; Thomas, Colleen S; Pankratz, V Shane; Allen, Mariet; Nguyen, Thuy; Malphrus, Kimberly G; Ma, Li; Bisceglio, Gina D; Roberts, Rosebud O; Lucas, John A; Smith, Glenn E; Ivnik, Robert J; Machulda, Mary M; Graff-Radford, Neill R; Petersen, Ronald C; Younkin, Steven G; Ertekin-Taner, Nilüfer

2015-01-01

We tested association of nine late-onset Alzheimer's disease (LOAD) risk variants from genome-wide association studies (GWAS) with memory and progression to mild cognitive impairment (MCI) or LOAD (MCI/LOAD) in older Caucasians, cognitively normal at baseline and longitudinally evaluated at Mayo Clinic Rochester and Jacksonville (n>2000). Each variant was tested both individually and collectively using a weighted risk score. APOE-e4 associated with worse baseline memory and increased decline with highly significant overall effect on memory. CLU-rs11136000-G associated with worse baseline memory and incident MCI/LOAD. MS4A6A-rs610932-C associated with increased incident MCI/LOAD and suggestively with lower baseline memory. ABCA7-rs3764650-C and EPHA1-rs11767557-A associated with increased rates of memory decline in subjects with a final diagnosis of MCI/LOAD. PICALM-rs3851179-G had an unexpected protective effect on incident MCI/LOAD. Only APOE-inclusive risk scores associated with worse memory and incident MCI/LOAD. The collective influence of the nine top LOAD GWAS variants on memory decline and progression to MCI/LOAD appears limited. Discovery of biologically functional variants at these loci may uncover stronger effects on memory and incident disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Intracellular pH regulation in hepatocytes isolated from three teleost species.

PubMed

Furimsky, M; Moon, T W; Perry, S F

1999-09-01

The mechanisms of intracellular pH (pH(i)) regulation were studied in hepatocytes isolated from three species of teleost: rainbow trout (Oncorhynchus mykiss), black bullhead (Ameiurus melas) and American eel (Anguilla rostrata). Intracellular pH was monitored over time using the pH-sensitive fluorescent dye BCECF in response to acid loading under control conditions and in different experimental media containing either low Na(+) or Cl(-) concentrations, the Na(+)-H(+) exchanger blocker amiloride or the blocker of the V-type H(+)-ATPase, bafilomycin A(1). In trout and bullhead hepatocytes, recovery to an intracellular acid load occurred principally by way of a Na(+)-dependent amiloride-sensitive Na(+)-H(+) exchanger. In eel hepatocytes, the Na(+)-H(+) exchanger did not contribute to recovery to an acid load though evidence suggests that it is present on the cell membrane and participates in the maintenance of steady-state pH(i). The V-type H(+)-ATPase did not participate in recovery to an acid load in any species. A Cl(-)-HCO(3)(-) exchanger may play a role in recovery to an acid load in eel hepatocytes by switching off and retaining base that would normally be tonically extruded. Thus, it is clear that hepatocytes isolated from the three species are capable of regulating pH(i), principally by way of a Na(+)-H(+) exchanger and a Cl(-)-HCO(3)(-) exchanger, but do not exploit identical mechanisms for pH(i) recovery. J. Exp. Zool. 284:361-367, 1999. Copyright 1999 Wiley-Liss, Inc.

(p-ClPhSe)2 stimulates carbohydrate metabolism and reverses the metabolic alterations induced by high fructose load in rats.

PubMed

Quines, Caroline B; Rosa, Suzan G; Chagas, Pietro M; Velasquez, Daniela; Prado, Vinicius C; Nogueira, Cristina W

2017-09-01

The modern life leads to excess consumption of food rich in fructose; however, the long-term changes in carbohydrate and lipid metabolism could lead to metabolic dysfunction in humans. The present study evaluated the in vitro insulin-mimetic action of p-chloro-diphenyl diselenide (p-ClPhSe) 2 . The second aim of this study was to investigate if (p-ClPhSe) 2 reverses metabolic dysfunction induced by fructose load in Wistar rats. The insulin-mimetic action of (p-ClPhSe) 2  at concentrations of 50 and 100 μM was determined in slices of rat skeletal muscle. (p-ClPhSe) 2  at a concentration of 50 μM stimulated the glucose uptake by 40% in skeletal muscle. A dose-response curve revealed that (p-ClPhSe) 2  at a dose of 25 mg/kg reduced (∼20%) glycemia in rats treated with fructose (5 g/kg, i.g.). The administration of fructose impaired the liver homeostasis and (p-ClPhSe) 2 (25 mg/kg) protected against the increase (∼25%) in the G-6-Pase and isocitrate dehydrogenase activities and reduced the triglyceride content (∼25%) in the liver. (p-ClPhSe) 2 regulated the liver homeostasis by stimulating hexokinase activity (∼27%), regulating the TCA cycle activity (increased the ATP and citrate synthase activity (∼15%)) and increasing the glycogen levels (∼67%). In conclusion, (p-ClPhSe) 2 stimulated carbohydrate metabolism and reversed metabolic dysfunction in rats fed with fructose. Copyright © 2017 Elsevier Ltd. All rights reserved.

Beyond the Dedicated Education Unit: Using Cognitive Load Theory to Guide Clinical Placement.

PubMed

Mulcock, Pamela McPhie; Grassley, Jane; Davis, Michael; White, Kathryn

2017-02-01

Navigating multiple instructors and clinical agencies can impair students' learning by increasing their cognitive load and perceived stress. This study used cognitive load theory to guide the home base clinical model (HBCM), which assigned students to the same faculty and hospital unit for two consecutive medical-surgical clinical courses. The study used a quasi-experimental three-group design to evaluate the effects of the HBCM on students' perceived stress, compared with groups who changed hospital or instructor. A 10-point visual analog scale measured students' perceived stress on nine clinical tasks. The study recruited 140 participants. Reductions in mean stress were greater for the HBCM groups than the other two groups. The study findings challenge the current practice of placing students with changing faculty and facilities. The HBCM demonstrates potential as an effective model for increasing students' ability to learn by decreasing their cognitive load and subsequent stress in their clinical placements. [J Nurs Educ. 2017;56(2):105-109.]. Copyright 2017, SLACK Incorporated.

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses.

PubMed

Xie, Heping; Wang, Fuxing; Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = -0.11, 95% CI = [-0.19, -0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = -0.70, 95% CI = [-1.02, -0.38], p < 0.001), as well as dtransfer for cueing (β = -0.60, 95% CI = [-0.92, -0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning.

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses

PubMed Central

Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = −0.11, 95% CI = [−0.19, −0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = −0.70, 95% CI = [−1.02, −0.38], p < 0.001), as well as dtransfer for cueing (β = −0.60, 95% CI = [−0.92, −0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning. PMID:28854205

Multitasking during social interactions in adolescence and early adulthood

PubMed Central

Mills, Kathryn L.; Dumontheil, Iroise; Speekenbrink, Maarten; Blakemore, Sarah-Jayne

2015-01-01

Multitasking is part of the everyday lives of both adolescents and adults. We often multitask during social interactions by simultaneously keeping track of other non-social information. Here, we examined how keeping track of non-social information impacts the ability to navigate social interactions in adolescents and adults. Participants aged 11–17 and 22–30 years old were instructed to carry out two tasks, one social and one non-social, within each trial. The social task involved referential communication, requiring participants to use social cues to guide their decisions, which sometimes required taking a different perspective. The non-social task manipulated cognitive load by requiring participants to remember non-social information in the form of one two-digit number (low load) or three two-digit numbers (high load) presented before each social task stimulus. Participants showed performance deficits when under high cognitive load and when the social task involved taking a different perspective, and individual differences in both trait perspective taking and working memory capacity predicted performance. Overall, adolescents were less adept at multitasking than adults when under high cognitive load. These results suggest that multitasking during social interactions incurs performance deficits, and that adolescents are more sensitive than adults to the effects of cognitive load while multitasking. PMID:26715991

Multitasking during social interactions in adolescence and early adulthood.

PubMed

Mills, Kathryn L; Dumontheil, Iroise; Speekenbrink, Maarten; Blakemore, Sarah-Jayne

2015-11-01

Multitasking is part of the everyday lives of both adolescents and adults. We often multitask during social interactions by simultaneously keeping track of other non-social information. Here, we examined how keeping track of non-social information impacts the ability to navigate social interactions in adolescents and adults. Participants aged 11-17 and 22-30 years old were instructed to carry out two tasks, one social and one non-social, within each trial. The social task involved referential communication, requiring participants to use social cues to guide their decisions, which sometimes required taking a different perspective. The non-social task manipulated cognitive load by requiring participants to remember non-social information in the form of one two-digit number (low load) or three two-digit numbers (high load) presented before each social task stimulus. Participants showed performance deficits when under high cognitive load and when the social task involved taking a different perspective, and individual differences in both trait perspective taking and working memory capacity predicted performance. Overall, adolescents were less adept at multitasking than adults when under high cognitive load. These results suggest that multitasking during social interactions incurs performance deficits, and that adolescents are more sensitive than adults to the effects of cognitive load while multitasking.

The effect of integrating constructivist and evidence-based practice on baccalaureate nursing student's cognitive load and learning performance in a research course.

PubMed

Hsieh, Suh-Ing; Hsu, Li-Ling; Huang, Tzu-Hsin

2016-07-01

Baccalaureate nursing students perceive research as unattractive, doubt the value of nursing research, and do not appreciate the link of research with practice. No studies have examined students' cognitive load during an evidence-based practice research course versus a traditional research course. To assess the effect of integrating constructivist theories and evidence-based practice on student cognitive load and learning performance in a research course. A true experimental study. A Registered Nurse-to-Bachelor of Science in Nursing program. Six classes of second-year students. Students were randomly allocated to the control group (two classes) or the experimental group (two classes) using cluster randomization. The control group underwent "traditional research"; the experimental group experienced "integrating evidence-based practice into research." Instruments for outcome assessment include the Cognitive Load Scale, cognitive test, team critique paper, and qualitative feedback on course satisfaction. The between-subjects effects were compared by Analysis of Covariance. The experimental group had significantly higher mental load (8.74 vs. 7.27, p<.001), mental effort (11.07 vs. 10.07, p=.009), mental efficiency (0.33 vs. -0.31, p<.001), and research knowledge (70.61 vs. 44.92, p<.001) than the control group. The experimental group had better critique paper scores in introduction (92.80%), literature review (91.70%), and assignment requirement and writing (89.40%). Some experimental learners expressed satisfaction with learning evidence-based practice (17.78%) and critiquing a research article (7.78%). Integrating evidence-based practice into a research course not only improved the research knowledge of baccalaureate nursing students, but also increased their mental load, mental effort, and mental efficiency. Additional studies may track learners' responses to different learning systems using the developed instrument to measure the three types of cognitive load. These findings may help educators design more effective and interesting curricula for integrating research and evidence-based practice into the studies of student nurses. Copyright © 2016. Published by Elsevier Ltd.

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 completed by comparing lab grade averages, final exam averages, and final course grade averages between the two groups. Participant mental effort survey results showed significant positive effects of technology in reducing cognitive load for two laboratory investigations. One investigation revealed a significant difference in achievement measured by lab grade average comparisons. Although results of this study are inconclusive as to the usefulness of technology-driven investigations to affect learning, recommendations for further study are discussed.

Cognitive Load Selectively Interferes with Utilitarian Moral Judgment

PubMed Central

Greene, Joshua D.; Morelli, Sylvia A.; Lowenberg, Kelly; Nystrom, Leigh E.; Cohen, Jonathan D.

2008-01-01

Traditional theories of moral development emphasize the role of controlled cognition in mature moral judgment, while a more recent trend emphasizes intuitive and emotional processes. Here we test a dual-process theory synthesizing these perspectives. More specifically, our theory associates utilitarian moral judgment (approving of harmful actions that maximize good consequences) with controlled cognitive processes and associates non-utilitarian moral judgment with automatic emotional responses. Consistent with this theory, we find that a cognitive load manipulation selectively interferes with utilitarian judgment. This interference effect provides direct evidence for the influence of controlled cognitive processes in moral judgment, and utilitarian moral judgment more specifically. PMID:18158145

Interaction of threat and verbal working memory in adolescents.

PubMed

Patel, Nilam; Vytal, Katherine; Pavletic, Nevia; Stoodley, Catherine; Pine, Daniel S; Grillon, Christian; Ernst, Monique

2016-04-01

Threat induces a state of sustained anxiety that can disrupt cognitive processing, and, reciprocally, cognitive processing can modulate an anxiety response to threat. These effects depend on the level of cognitive engagement, which itself varies as a function of task difficulty. In adults, we recently showed that induced anxiety impaired working memory accuracy at low and medium but not high load. Conversely, increasing the task load reduced the physiological correlates of anxiety (anxiety-potentiated startle). The present work examines such threat-cognition interactions as a function of age. We expected threat to more strongly impact working memory in younger individuals by virtue of putatively restricted cognitive resources and weaker emotion regulation. This was tested by examining the influence of age on the interaction of anxiety and working memory in 25 adolescents (10 to 17 years) and 25 adults (22 to 46 years). Working memory load was manipulated using a verbal n-back task. Anxiety was induced using the threat of an aversive loud scream and measured via eyeblink startle. Findings revealed that, in both age groups, accuracy was lower during threat than safe conditions at low and medium but not high load, and reaction times were faster during threat than safe conditions at high load but did not differ at other loads. Additionally, anxiety-potentiated startle was greater during low and medium than high load. Thus, the interactions of anxiety with working memory appear similar in adolescents and adults. Whether these similarities reflect common neural mechanisms would need to be assessed using functional neuroimaging. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

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…

Decreasing Cognitive Load for Novice EFL Learners: Effects of Question and Descriptive Advance Organizers in Facilitating EFL Learners' Comprehension of an Animation-Based Content Lesson

ERIC Educational Resources Information Center

Lin, Huifen; Chen, Tsuiping

2006-01-01

Cognitive load can be defined as the amount of mental effort that performing a specific task imposes on a learner's cognitive system. It can be measured by the number of new concepts embedded in a learning task. English as a Foreign Language (EFL) learners, with their limited English proficiency and minimal entry knowledge of a subject matter,…

Integrating Cognitive Linguistics Insights into Data-Driven Learning: Teaching Vertical Prepositions

ERIC Educational Resources Information Center

Kilimci, Abdurrahman

2017-01-01

The present study investigates the impact of the integration of the Cognitive Linguistics (CL) pedagogy into Data-driven learning (DDL) on the learners' acquisition of two sets of English spatial prepositions of verticality, "over/under" and "above/below." The study followed a quasi-experimental design with a control and an…

Is the alkaline tide a signal to activate metabolic or ionoregulatory enzymes in the dogfish shark (Squalus acanthias)?

PubMed

Wood, Chris M; Kajimura, Makiko; Mommsen, Thomas P; Walsh, Patrick J

2008-01-01

Experimental metabolic alkalosis is known to stimulate whole-animal urea production and active ion secretion by the rectal gland in the dogfish shark. Furthermore, recent evidence indicates that a marked alkaline tide (systemic metabolic alkalosis) follows feeding in this species and that the activities of the enzymes of the ornithine-urea cycle (OUC) for urea synthesis in skeletal muscle and liver and of energy metabolism and ion transport in the rectal gland are increased at this time. We therefore evaluated whether alkalosis and/or NaCl/volume loading (which also occurs with feeding) could serve as a signal for activation of these enzymes independent of nutrient loading. Fasted dogfish were infused for 20 h with either 500 mmol L(-1) NaHCO3 (alkalosis + volume expansion) or 500 mmol L(-1) NaCl (volume expansion alone), both isosmotic to dogfish plasma, at a rate of 3 mL kg(-1) h(-1). NaHCO3 infusion progressively raised arterial pH to 8.28 (control = 7.85) and plasma [HCO3-] to 20.8 mmol L(-1) (control = 4.5 mmol L(-1)) at 20 h, with unchanged arterial P(CO2), whereas NaCl/volume loading had no effect on blood acid-base status. Rectal gland Na+,K+-ATPase activity was increased 50% by NaCl loading and more than 100% by NaHCO3 loading, indicating stimulatory effects of both volume expansion and alkalosis. Rectal gland lactate dehydrogenase activity was elevated 25% by both treatments, indicating volume expansion effects only, whereas neither treatment increased the activities of the aerobic enzymes citrate synthase, NADP-isocitrate dehydrogenase, or the ketone body-utilizing enzyme beta-hydroxybutyrate dehydrogenase in the rectal gland or liver. The activity of ornithine-citrulline transcarbamoylase in skeletal muscle was doubled by NaHCO3 infusion, but neither treatment altered the activities of other OUC-related enzymes (glutamine synthetase, carbamoylphosphate synthetase III). We conclude that both the alkaline tide and salt loading/volume expansion act as signals to activate some but not all of the elevated metabolic pathways and ionoregulatory mechanisms needed during processing of a meal.

On the Post-Compaction Evolution of Tensile Strength of Sodium Chloride-Starch Mixture Tablets.

PubMed

Radojevic, Jovana; Zavaliangos, Antonios

2017-08-01

This study focuses on the evolution of mechanical behavior of starch and sodium chloride (NaCl) mixture tablets after compaction. This type of mixture has attracted attention in the past because such tablets exhibit lower tensile strengths than the ones of its individual components. Here we demonstrate that the strengths of NaCl-starch mixtures and NaCl tablets evolve after compaction in an opposite way. When stored at relative humidity of 60%, NaCl tablets strengthen with time, whereas NaCl-starch mixtures weaken. To explain this behavior, we propose that in the NaCl-starch mixture, the presence of 2 materials with significantly different elastic moduli leads to creation of tensile stresses at the stiffer NaCl-NaCl contacts. Such tensile stresses lead to a reduction in strength of the compacted mixtures by negating a local dissolution-reprecipitation mechanism, which strengthens the NaCl-NaCl in pure NaCl tablet. This effect is proven by experimental results from NaCl specimens diametrically loaded during storage. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Surprise responses in the human brain demonstrate statistical learning under high concurrent cognitive demand

NASA Astrophysics Data System (ADS)

Garrido, Marta Isabel; Teng, Chee Leong James; Taylor, Jeremy Alexander; Rowe, Elise Genevieve; Mattingley, Jason Brett

2016-06-01

The ability to learn about regularities in the environment and to make predictions about future events is fundamental for adaptive behaviour. We have previously shown that people can implicitly encode statistical regularities and detect violations therein, as reflected in neuronal responses to unpredictable events that carry a unique prediction error signature. In the real world, however, learning about regularities will often occur in the context of competing cognitive demands. Here we asked whether learning of statistical regularities is modulated by concurrent cognitive load. We compared electroencephalographic metrics associated with responses to pure-tone sounds with frequencies sampled from narrow or wide Gaussian distributions. We showed that outliers evoked a larger response than those in the centre of the stimulus distribution (i.e., an effect of surprise) and that this difference was greater for physically identical outliers in the narrow than in the broad distribution. These results demonstrate an early neurophysiological marker of the brain's ability to implicitly encode complex statistical structure in the environment. Moreover, we manipulated concurrent cognitive load by having participants perform a visual working memory task while listening to these streams of sounds. We again observed greater prediction error responses in the narrower distribution under both low and high cognitive load. Furthermore, there was no reliable reduction in prediction error magnitude under high-relative to low-cognitive load. Our findings suggest that statistical learning is not a capacity limited process, and that it proceeds automatically even when cognitive resources are taxed by concurrent demands.

Effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome.

PubMed

Zeinalzadeh, Afsaneh; Talebian, Saeed; Naghdi, Soofia; Salavati, Mahyar; Nazary-Moghadam, Salman; Zeynalzadeh Ghoochani, Bahareh

2018-04-01

To compare the effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome (PFPS). Twenty-eight PFPS patients and 28 controls participated in the study. Postural control was assessed in isolation as well as with visual manipulation and cognitive loading on symptomatic limb. The outcome measures of postural control were quantified in terms of area, anterior-posterior (AP), medial-lateral (ML), and mean velocity (MV) of the displacements of center of pressure (COP). In addition, cognitive performance (auditory Stroop task) was measured in the forms of average reaction time and error ratio in baseline (sitting) and different postural conditions. PFPS subjects showed greater increases in area (p = 0.01), AP (p = 0.01), and ML (p = 0.05) displacements of COP in the blindfolded tasks as compared to control group. However, cognitive load did not differently affect postural control in the two groups. Although PFPS and control group had similar reaction times in the sitting position (p = 0.29), PFPS subjects had longer reaction times than healthy subjects in dual task conditions (p = 0.04). Visual inputs seem to be essential for discriminating postural control between PFPS and healthy individuals. PFPS patients biased toward decreasing cognitive performance more than healthy subjects when they perform the single leg stance and cognitive task concurrently.

Anticholinergic load negatively correlates with recovery of cognitive activities of daily living for geriatric patients after stroke in the convalescent stage.

PubMed

Kose, E; Hirai, T; Seki, T; Hidaka, S; Hamamoto, T

2018-05-16

Anticholinergic drugs are associated with risks of falls, confusion and cognitive dysfunction. However, the effect of anticholinergic drug use on rehabilitation outcomes after a stroke is poorly documented. We therefore aimed to establish whether the anticholinergic load was associated with functional recovery among geriatric patients convalescing after stroke. Consecutive geriatric stroke patients admitted and discharged from a convalescence rehabilitation ward between 2010 and 2016 were included in this retrospective cohort study. Anticholinergic load was assessed by the Anticholinergic Risk Scale (ARS), and functional recovery was assessed by the Functional Independence Measure (FIM). The primary outcome was cognitive FIM (FIM-C) gain, but we also assessed the interaction of other putative factors identified from univariate analysis. Multivariate analyses were performed, adjusting for confounding factors. We included 418 participants (171 males, 247 females) with a median age of 78 years (interquartile range, 72-84 years). Multiple regression analysis revealed that ARS change, length of stay, and epilepsy were independently and negatively correlated with cognitive FIM gain. Multiple logistic regression analysis indicated that the "Comprehension" and "Memory" items of the cognitive FIM gain were independently and negatively associated with anticholinergic load. A causal relationship cannot be established, but increased ARS scores during hospitalization may predict limited cognitive functional improvement in geriatric patients after stroke. Alternatively, cognitive impairment may lead to increased use of anticholinergic drugs. © 2018 John Wiley & Sons Ltd.

Monitoring the response of patients with cutaneous leishmaniasis to treatment with pentamidine isethionate by quantitative real-time PCR, and identification of Leishmania parasites not responding to therapy.

PubMed

Mans, D R A; Kent, A D; Hu, R V; Lai A Fat, E J; Schoone, G J; Adams, E R; Rood, E J; Alba, S; Sabajo, L O A; Lai A Fat, R F; de Vries, H J C; Schallig, H D F H

2016-08-01

Leishmania (Viannia) guyanensis is believed to be the principal cause of cutaneous leishmaniasis (CL) in Suriname. This disease is treated with pentamidine isethionate (PI), but treatment failure has increasingly been reported. To evaluate PI for its clinical efficacy, to compare parasite load, and to assess the possibility of treatment failure due to other infecting Leishmania species. Parasite load of patients with CL was determined in skin biopsies using real-time quantitative PCR before treatment and 6 and 12 weeks after treatment. Clinical responses were evaluated at week 12 and compared with parasite load. In parallel, molecular species differentiation was performed. L. (V.) guyanensis was the main infecting species in 129 of 143 patients (about 90%). PI treatment led to a significant decrease (P < 0.001) in parasite counts, and cured about 75% of these patients. Treatment failure was attributable to infections with Leishmania (Viannia) braziliensis, Leishmania (Leishmania) amazonensis and L. (V.) guyanensis (1/92, 1/92 and 22/92 evaluable cases, respectively). There was substantial agreement beyond chance between the parasite load at week 6 and the clinical outcome at week 12, as indicated by the κ value of 0.61. L. (V.) guyanensis is the main infecting species of CL in Suriname, followed by L. (V.) braziliensis and L. (L.) amazonensis. Furthermore, patient response to PI can be better anticipated based on the parasite load 6 weeks after the treatment rather than on parasite load before treatment. © 2015 The Authors Clinical and Experimental Dermatology published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists, North American Clinical Dermatologic Society and St Johns Dermatological Society.

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. © 2016 American Association of Anatomists.

Pointing and tracing gestures may enhance anatomy and physiology learning.

PubMed

Macken, Lucy; Ginns, Paul

2014-07-01

Currently, instructional effects generated by Cognitive load theory (CLT) are limited to visual and auditory cognitive processing. In contrast, "embodied cognition" perspectives suggest a range of gestures, including pointing, may act to support communication and learning, but there is relatively little research showing benefits of such "embodied learning" in the health sciences. This study investigated whether explicit instructions to gesture enhance learning through its cognitive effects. Forty-two university-educated adults were randomly assigned to conditions in which they were instructed to gesture, or not gesture, as they learnt from novel, paper-based materials about the structure and function of the human heart. Subjective ratings were used to measure levels of intrinsic, extraneous and germane cognitive load. Participants who were instructed to gesture performed better on a knowledge test of terminology and a test of comprehension; however, instructions to gesture had no effect on subjective ratings of cognitive load. This very simple instructional re-design has the potential to markedly enhance student learning of typical topics and materials in the health sciences and medicine.

Time and Cognitive Load in Working Memory

ERIC Educational Resources Information Center

Barrouillet, Pierre; Bernardin, Sophie; Portrat, Sophie; Vergauwe, Evie; Camos, Valerie

2007-01-01

According to the time-based resource-sharing model (P. Barrouillet, S. Bernardin, & V. Camos, 2004), the cognitive load a given task involves is a function of the proportion of time during which it captures attention, thus impeding other attention-demanding processes. Accordingly, the present study demonstrates that the disruptive effect on…

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…

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…

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…

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…

Rethinking the Boundaries of Cognitive Load Theory in Complex Learning

ERIC Educational Resources Information Center

Kalyuga, Slava; Singh, Anne-Marie

2016-01-01

In the traditional framework of cognitive load theory, it is assumed that the acquisition of domain-specific knowledge structures (or schemas) is the only instructional goal, and therefore, the theory is applicable to any instructional task. Accordingly, the basic concepts of intrinsic (productive) and extraneous (unproductive) types of cognitive…

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…

Cognitive Load Theory and Music Instruction

ERIC Educational Resources Information Center

Owens, Paul; Sweller, John

2008-01-01

In two experiments, the principles of cognitive load theory were applied to the design of alternatives to conventional music instruction hypothesised to facilitate learning. Experiment 1 demonstrated that spatial integration of visual text and musical notation, and dual-modal delivery of auditory text and musical notation, were superior to the…

Performance, Cognitive Load, and Behaviour of Technology-Assisted English Listening Learning: From CALL to MALL

ERIC Educational Resources Information Center

Chang, Chi-Cheng; Warden, Clyde A.; Liang, Chaoyun; Chou, Pao-Nan

2018-01-01

This study examines differences in English listening comprehension, cognitive load, and learning behaviour between outdoor ubiquitous learning and indoor computer-assisted learning. An experimental design, employing a pretest-posttest control group is employed. Randomly assigned foreign language university majors joined either the experimental…

Is improved lane keeping during cognitive load caused by increased physical arousal or gaze concentration toward the road center?

PubMed

Li, Penghui; Markkula, Gustav; Li, Yibing; Merat, Natasha

2018-08-01

Driver distraction is one of the main causes of motor-vehicle accidents. However, the impact on traffic safety of tasks that impose cognitive (non-visual) distraction remains debated. One particularly intriguing finding is that cognitive load seems to improve lane keeping performance, most often quantified as reduced standard deviation of lateral position (SDLP). The main competing hypotheses, supported by current empirical evidence, suggest that cognitive load improves lane keeping via either increased physical arousal, or higher gaze concentration toward the road center, but views are mixed regarding if, and how, these possible mediators influence lane keeping performance. Hence, a simulator study was conducted, with participants driving on a straight city road section whilst completing a cognitive task at different levels of difficulty. In line with previous studies, cognitive load led to increased physical arousal, higher gaze concentration toward the road center, and higher levels of micro-steering activity, accompanied by improved lane keeping performance. More importantly, during the high cognitive task, both physical arousal and gaze concentration changed earlier in time than micro-steering activity, which in turn changed earlier than lane keeping performance. In addition, our results did not show a significant correlation between gaze concentration and physical arousal on the level of individual task recordings. Based on these findings, various multilevel models for micro-steering activity and lane keeping performance were conducted and compared, and the results suggest that all of the mechanisms proposed by existing hypotheses could be simultaneously involved. In other words, it is suggested that cognitive load leads to: (i) an increase in arousal, causing increased micro-steering activity, which in turn improves lane keeping performance, and (ii) an increase in gaze concentration, causing lane keeping improvement through both (a) further increased micro-steering activity and (b) a tendency to steer toward the gaze target. Copyright © 2018 Elsevier Ltd. All rights reserved.

Development, Characterization, and In Vitro Biological Performance of Fluconazole-Loaded Microemulsions for the Topical Treatment of Cutaneous Leishmaniasis

PubMed Central

Graminha, Márcia; Cerecetto, Hugo; González, Mercedes

2015-01-01

Cutaneous leishmaniasis (CL) is a resistant form of leishmaniasis that is caused by a parasite belonging to the genus Leishmania. FLU-loaded microemulsions (MEs) were developed by phase diagram for topical administration of fluconazole (FLU) as prominent alternative to combat CL. Three MEs called F1, F2, and F3 (F1—60% 50 M phosphate buffer at pH 7.4 (PB) as aqueous phase, 10% cholesterol (CHO) as oil phase, and 30% soy phosphatidylcholine/oil polyoxyl-60 hydrogenated castor oil/sodium oleate (3/8/6) (S) as surfactant; F2—50% PB, 10% CHO, and 40% S; F3—40% PB, 10% CHO, and 50 % S) were characterized by droplet size analysis, zeta potential analysis, X-ray diffraction, continuous flow, texture profile analysis, and in vitro bioadhesion. MEs presented pseudoplastic flow and thixotropy was dependent on surfactant concentration. Droplet size was not affected by FLU. FLU-loaded MEs improved the FLU safety profile that was evaluated using red cell haemolysis and in vitro cytotoxicity assays with J-774 mouse macrophages. FLU-unloaded MEs did not exhibit leishmanicidal activity that was performed using MTT colourimetric assays; however, FLU-loaded MEs exhibited activity. Therefore, these MEs have potential to modulate FLU action, being a promising platform for drug delivery systems to treat CL. PMID:25650054

Deciding the fate of others: the cognitive underpinnings of racially biased juror decision making.

PubMed

Kleider, Heather M; Knuycky, Leslie R; Cavrak, Sarah E

2012-01-01

In criminal law, jurors are supposed to ignore defendant race when considering factual matters of culpability. However, when judging the merits of a criminal case, jurors' ability (or inability) to avoid bias may affect verdicts. Fact-based decision making expend cognitive resources, while heuristic-based decisions (e.g., using criminal stereotypes) conserve resources. Here, we investigated whether differences in cognitive resources and prejudice attitudes about Blacks influenced trial outcomes. We tested the impact of working memory capacity (WMC), cognitive load, prejudice, and target race (Black, White) on penalties ascribed to fictional criminal defendants in ambiguous-fact cases. Results showed that when "loaded," prejudiced-low-WMC persons supported guilty verdicts with higher confidence more often for Black than White defendants. Conversely, regardless of WMC or prejudice attitude, participants penalized White defendants more often when not loaded. We suggest that cognitive resources and prejudice attitude influence fact-based decisions. Links to juror judgments and potential trial outcomes are discussed.

Working memory regulates trait anxiety-related threat processing biases.

PubMed

Booth, Robert W; Mackintosh, Bundy; Sharma, Dinkar

2017-06-01

High trait anxious individuals tend to show biased processing of threat. Correlational evidence suggests that executive control could be used to regulate such threat-processing. On this basis, we hypothesized that trait anxiety-related cognitive biases regarding threat should be exaggerated when executive control is experimentally impaired by loading working memory. In Study 1, 68 undergraduates read ambiguous vignettes under high and low working memory load; later, their interpretations of these vignettes were assessed via a recognition test. Trait anxiety predicted biased interpretation of social threat vignettes under high working memory load, but not under low working memory load. In Study 2, 53 undergraduates completed a dot probe task with fear-conditioned Japanese characters serving as threat stimuli. Trait anxiety predicted attentional bias to the threat stimuli but, again, this only occurred under high working memory load. Interestingly however, actual eye movements toward the threat stimuli were only associated with state anxiety, and this was not moderated by working memory load, suggesting that executive control regulates biased threat-processing downstream of initial input processes such as orienting. These results suggest that cognitive loads can exacerbate trait anxiety-related cognitive biases, and therefore represent a useful tool for assessing cognitive biases in future research. More importantly, since biased threat-processing has been implicated in the etiology and maintenance of anxiety, poor executive control may be a risk factor for anxiety disorders. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Brain beta-amyloid measures and magnetic resonance imaging atrophy both predict time-to-progression from mild cognitive impairment to Alzheimer’s disease

PubMed Central

Wiste, Heather J.; Vemuri, Prashanthi; Weigand, Stephen D.; Senjem, Matthew L.; Zeng, Guang; Bernstein, Matt A.; Gunter, Jeffrey L.; Pankratz, Vernon S.; Aisen, Paul S.; Weiner, Michael W.; Petersen, Ronald C.; Shaw, Leslie M.; Trojanowski, John Q.; Knopman, David S.

2010-01-01

Biomarkers of brain Aβ amyloid deposition can be measured either by cerebrospinal fluid Aβ42 or Pittsburgh compound B positron emission tomography imaging. Our objective was to evaluate the ability of Aβ load and neurodegenerative atrophy on magnetic resonance imaging to predict shorter time-to-progression from mild cognitive impairment to Alzheimer’s dementia and to characterize the effect of these biomarkers on the risk of progression as they become increasingly abnormal. A total of 218 subjects with mild cognitive impairment were identified from the Alzheimer’s Disease Neuroimaging Initiative. The primary outcome was time-to-progression to Alzheimer’s dementia. Hippocampal volumes were measured and adjusted for intracranial volume. We used a new method of pooling cerebrospinal fluid Aβ42 and Pittsburgh compound B positron emission tomography measures to produce equivalent measures of brain Aβ load from either source and analysed the results using multiple imputation methods. We performed our analyses in two phases. First, we grouped our subjects into those who were ‘amyloid positive’ (n = 165, with the assumption that Alzheimer's pathology is dominant in this group) and those who were ‘amyloid negative’ (n = 53). In the second phase, we included all 218 subjects with mild cognitive impairment to evaluate the biomarkers in a sample that we assumed to contain a full spectrum of expected pathologies. In a Kaplan–Meier analysis, amyloid positive subjects with mild cognitive impairment were much more likely to progress to dementia within 2 years than amyloid negative subjects with mild cognitive impairment (50 versus 19%). Among amyloid positive subjects with mild cognitive impairment only, hippocampal atrophy predicted shorter time-to-progression (P < 0.001) while Aβ load did not (P = 0.44). In contrast, when all 218 subjects with mild cognitive impairment were combined (amyloid positive and negative), hippocampal atrophy and Aβ load predicted shorter time-to-progression with comparable power (hazard ratio for an inter-quartile difference of 2.6 for both); however, the risk profile was linear throughout the range of hippocampal atrophy values but reached a ceiling at higher values of brain Aβ load. Our results are consistent with a model of Alzheimer’s disease in which Aβ deposition initiates the pathological cascade but is not the direct cause of cognitive impairment as evidenced by the fact that Aβ load severity is decoupled from risk of progression at high levels. In contrast, hippocampal atrophy indicates how far along the neurodegenerative path one is, and hence how close to progressing to dementia. Possible explanations for our finding that many subjects with mild cognitive impairment have intermediate levels of Aβ load include: (i) individual subjects may reach an Aβ load plateau at varying absolute levels; (ii) some subjects may be more biologically susceptible to Aβ than others; and (iii) subjects with mild cognitive impairment with intermediate levels of Aβ may represent individuals with Alzheimer’s disease co-existent with other pathologies. PMID:20935035

[Preliminary study on transdermal characteristics and sunface anesthetic effects of lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome in animals].

PubMed

Wang, Yue; Zhang, Lianyun; Li, Changyi; Wang, Hanjie; Li, Qin

2015-07-01

To prepare a new dental topical anesthetics, lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome (LID-TAT-N), and to evaluate its transdermal properties and topical anesthesia effects. LID-TAT-N was prepared using reverse-phase evaporation method, and lidocaine loaded conventional liposome (LID-CL) was prepared in the same manner as positive control. The diameter, ζ potential and encapsulation efficiency of LID-TAT-N and LID-CL were measured. The skin permeation of LID-TAT-N was examined, and compared with LID-CL and lidocaine injection (LID-IJ, as negative control), using a Franz diffusion cell mounted with depilated mouse skin in vitro for 12 hours. Each experiment was repeated six times. The anesthetic effect of the new topical anesthetic was investigated on the cornea of rabbits. The mean diameter of LID-TAT-N was smaller than that of LID-CL [(152.7 ± 10.6) nm vs. (259.5 ± 15.5) nm, P < 0.01]. The 12 h cumulative permeation amount was significantly higher in LID-TAT-N group [(1 340.0 ± 97.5) µg · cm(-2)] than those of LID-CL and LID-IJ groups [(1 060.6 ± 80.2), (282.6 ± 65.1) µg · cm(-2), respectively, P < 0.05]. Rabbit corneal reflex results showed that LID-TAT-N had anesthetic effect and the duration of analgesia [(24.8 ± 2.8) min] was also longer than that of LID-IJ [(14.5 ± 2.3) min, P < 0.05]. LID-TAT-N had good transdermal ability, and the advanced skin penetration feature can improve its tropical anesthetic effect.

Sulfate-chloride exchange by lobster hepatopancreas is regulated by pH-sensitive modifier sites

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

Cattey, M.A.; Ahearn, G.A.; Gerencser, G.A.

1991-03-15

{sup 35}SO{sub 4}{sup 2{minus}} uptake by Atlantic lobster (Homarus americanus) hepatopancreatic epithelial brush border membrane vesicles (BBMV) was stimulated by internal Cl{sup {minus}}, but not internal HCO{sub 3}{sup {minus}}, or external Na{sup +}. Sulfate-chloride exchange was stimulated by inside positive, and inhibited by inside negative, trans-membrane K diffusion potentials. {sup 35}SO{sub 4}{sup 2{minus}}-Cl{sup {minus}} exchange was strongly inhibited by 4,4{prime} diisothiocyanostilbene-2,2{prime}-disulfonic acid (DIDS), 4-acetamido-4{prime}-isotheocynaostilbene-2,2{prime}-disulfonic acid, (SITS), and thiosulfate. Chloride, bicarbonate, furosamide, and bumetanide slightly, yet significantly, cis-inhibited {sup 35}SO{sub 4}{sup 2{minus}}-Cl{sup {minus}} exchange. Altering bilateral pH from 8.0 to 5.4 stimulated {sup 35}SO{sub 4}{sup 2{minus}}-Cl{sup {minus}} exchange when vesicles weremore » loaded with Cl{sup {minus}}, but reduced bilateral pH alone or the presence of pH gradients did not affect {sup 35}SO{sub 4}{sup 2{minus}} transport in the absence of internal Cl{sup {minus}}. {sup 36}Cl uptake into SO{sub 4}{sup 2{minus}}-loaded BBMV was stimulated by an internal negative membrane potential and inhibited when the interior was electrically positive. A model is proposed which suggests that SO{sub 4}{sup 2{minus}}-Cl{sup {minus}} exchange is regulated by internal and external pH-sensitive modifier sites on the anion antiporter and by coupling to the electrogenic 2 Na{sup +}/1 H{sup +} antiporter and by coupling to the electrogenic 2 Na{sup +}/1 H{sup +} antiporter on the same membrane.« less

Use of Combined Biogeochemical Model Approaches and Empirical Data to Assess Critical Loads of Nitrogen

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

Fenn, Mark E.; Driscoll, Charles; Zhou, Qingtao

2015-01-01

Empirical and dynamic biogeochemical modelling are complementary approaches for determining the critical load (CL) of atmospheric nitrogen (N) or other constituent deposition that an ecosystem can tolerate without causing ecological harm. The greatest benefits are obtained when these approaches are used in combination. Confounding environmental factors can complicate the determination of empirical CLs across depositional gradients, while the experimental application of N amendments for estimating the CL does not realistically mimic the effects of chronic atmospheric N deposition. Biogeochemical and vegetation simulation models can provide CL estimates and valuable ecosystem response information, allowing for past and future scenario testing withmore » various combinations of environmental factors, pollutants, pollutant control options, land management, and ecosystem response parameters. Even so, models are fundamentally gross simplifications of the real ecosystems they attempt to simulate. Empirical approaches are vital as a check on simulations and CL estimates, to parameterize models, and to elucidate mechanisms and responses under real world conditions. In this chapter, we provide examples of empirical and modelled N CL approaches in ecosystems from three regions of the United States: mixed conifer forest, desert scrub and pinyon- juniper woodland in California; alpine catchments in the Rocky Mountains; and lakes in the Adirondack region of New York state.« less

Mechanism of oxidative DNA damage induction in a strict anaerobe, Prevotella melaninogenica.

PubMed

Takeuchi, T; Kato, N; Watanabe, K; Morimoto, K

2000-11-01

We investigated the mechanism of the oxidative DNA damage induction by exposure to O(2) in Prevotella melaninogenica, a strict anaerobe. Flow cytometry with hydroethidine and dichlorofluorescein diacetate showed that O(2) exposure generated O(2)*-) and H(2)O(2). Results of electron spin resonance with alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone and ethanol showed that O(2) exposure also induced *OH radical generation in P. melaninogenica loaded with FeCl(2) but not in samples without FeCl(2) loading. In P. melaninogenica, O(2) exposure increased 8-hydroxydeoxyguanosine (8OHdG), typical of oxidative DNA damage. Catalase inhibited the increase, but the *OH radical scavengers did not. Phenanthroline, a membrane-permeable Fe and Cu chelator, increased the 8OHdG induction. In FeCl(2)-loaded samples, induction of 8OHdG decreased. Addition of H(2)O(2) markedly increased 8OHdG levels. These results indicate that in P. melaninogenica, exposure to O(2) generated and accumulated O(2)* and H(2)O(2), and that a crypto-OH radical generated through H(2)O(2) was the active species in the 8OHdG induction.

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…

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…

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…

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…

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…

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…

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…

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…

Reading an Augmented Reality Book: An Exploration of Learners' Cognitive Load, Motivation, and Attitudes

ERIC Educational Resources Information Center

Cheng, Kun-Hung

2017-01-01

Since augmented reality (AR) has been increasingly applied in education recently, the investigation of students' learning experiences with AR could be helpful for educators to implement AR learning. With a quantitative survey using three questionnaires, this study explored the relationships among 153 students' perceived cognitive load, motivation,…

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…

A Knowledge Conversion Model Based on the Cognitive Load Theory for Architectural Design Education

ERIC Educational Resources Information Center

Wu, Yun-Wu; Liao, Shin; Wen, Ming-Hui; Weng, Kuo-Hua

2017-01-01

The education of architectural design requires balanced curricular arrangements of respectively theoretical knowledge and practical skills to really help students build their knowledge structures, particularly helping them in solving the problems of cognitive load. The purpose of this study is to establish an architectural design knowledge…

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…

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…

Visual Representations in Science Education: The Influence of Prior Knowledge and Cognitive Load Theory on Instructional Design Principles

ERIC Educational Resources Information Center

Cook, Michelle Patrick

2006-01-01

Visual representations are essential for communicating ideas in the science classroom; however, the design of such representations is not always beneficial for learners. This paper presents instructional design considerations providing empirical evidence and integrating theoretical concepts related to cognitive load. Learners have a limited…

Metacognitive Load--Useful, or Extraneous Concept? Metacognitive and Self-Regulatory Demands in Computer-Based Learning

ERIC Educational Resources Information Center

Schwonke, Rolf

2015-01-01

Instructional design theories such as the "cognitive load theory" (CLT) or the "cognitive theory of multimedia learning" (CTML) explain learning difficulties in (computer-based) learning usually as a result of design deficiencies that hinder effective schema construction. However, learners often struggle even in well-designed…

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…

Applications of Cognitive Load Theory to Multimedia-Based Foreign Language Learning: An Overview

ERIC Educational Resources Information Center

Chen, I-Jung; Chang, Chi-Cheng; Lee, Yen-Chang

2009-01-01

This article reviews the multimedia instructional design literature based on cognitive load theory (CLT) in the context of foreign language learning. Multimedia are of particular importance in language learning materials because they incorporate text, image, and sound, thus offering an integrated learning experience of the four language skills…

Anchoring in Numeric Judgments of Visual Stimuli

PubMed Central

Langeborg, Linda; Eriksson, Mårten

2016-01-01

This article investigates effects of anchoring in age estimation and estimation of quantities, two tasks which to different extents are based on visual stimuli. The results are compared to anchoring in answers to classic general knowledge questions that rely on semantic knowledge. Cognitive load was manipulated to explore possible differences between domains. Effects of source credibility, manipulated by differing instructions regarding the selection of anchor values (no information regarding anchor selection, information that the anchors are randomly generated or information that the anchors are answers from an expert) on anchoring were also investigated. Effects of anchoring were large for all types of judgments but were not affected by cognitive load or by source credibility in either one of the researched domains. A main effect of cognitive load on quantity estimations and main effects of source credibility in the two visually based domains indicate that the manipulations were efficient. Implications for theoretical explanations of anchoring are discussed. In particular, because anchoring did not interact with cognitive load, the results imply that the process behind anchoring in visual tasks is predominantly automatic and unconscious. PMID:26941684

Cognitive load and task condition in event- and time-based prospective memory: an experimental investigation.

PubMed

Khan, Azizuddin; Sharma, Narendra K; Dixit, Shikha

2008-09-01

Prospective memory is memory for the realization of delayed intention. Researchers distinguish 2 kinds of prospective memory: event- and time-based (G. O. Einstein & M. A. McDaniel, 1990). Taking that distinction into account, the present authors explored participants' comparative performance under event- and time-based tasks. In an experimental study of 80 participants, the authors investigated the roles of cognitive load and task condition in prospective memory. Cognitive load (low vs. high) and task condition (event- vs. time-based task) were the independent variables. Accuracy in prospective memory was the dependent variable. Results showed significant differential effects under event- and time-based tasks. However, the effect of cognitive load was more detrimental in time-based prospective memory. Results also revealed that time monitoring is critical in successful performance of time estimation and so in time-based prospective memory. Similarly, participants' better performance on the event-based prospective memory task showed that they acted on the basis of environment cues. Event-based prospective memory was environmentally cued; time-based prospective memory required self-initiation.

Working memory load eliminates the survival processing effect.

PubMed

Kroneisen, Meike; Rummel, Jan; Erdfelder, Edgar

2014-01-01

In a series of experiments, Nairne, Thompson, and Pandeirada (2007) demonstrated that words judged for their relevance to a survival scenario are remembered better than words judged for a scenario not relevant on a survival dimension. They explained this survival-processing effect by arguing that nature "tuned" our memory systems to process and remember fitness-relevant information. Kroneisen and Erdfelder (2011) proposed that it may not be survival processing per se that facilitates recall but the richness and distinctiveness with which information is encoded. To further test this account, we investigated how the survival processing effect is affected by cognitive load. If the survival processing effect is due to automatic processes or, alternatively, if survival processing is routinely prioritized in dual-task contexts, we would expect this effect to persist under cognitive load conditions. If the effect relies on cognitively demanding processes like richness and distinctiveness of encoding, however, the survival processing benefit should be hampered by increased cognitive load during encoding. Results were in line with the latter prediction, that is, the survival processing effect vanished under dual-task conditions.

Target loads of atmospheric sulfur deposition for the protection and recovery of acid-sensitive streams in the Southern Blue Ridge Province

Treesearch

Timothy Sullivan; Bernard Cosby; William Jackson

2011-01-01

An important tool in the evaluation of acidification damage to aquatic and terrestrial ecosystems is the critical load (CL), which represents the steady-state level of acidic deposition below which ecological damage would not be expected to occur, according to current scientific understanding. A deposition load intended to be protective of a specified resource...

Reduced firing rates of high threshold motor units in response to eccentric overload.

PubMed

Balshaw, Tom G; Pahar, Madhu; Chesham, Ross; Macgregor, Lewis J; Hunter, Angus M

2017-01-01

Acute responses of motor units were investigated during submaximal voluntary isometric tasks following eccentric overload (EO) and constant load (CL) knee extension resistance exercise. Ten healthy resistance-trained participants performed four experimental test sessions separated by 5 days over a 20 day period. Two sessions involved constant load and the other two used eccentric overload. EO and CL used both sessions for different target knee eccentric extension phases; one at 2 sec and the other at 4 sec. Maximal voluntary contractions (MVC) and isometric trapezoid efforts for 10 sec at 70% MVC were completed before and after each intervention and decomposed electromyography was used to measure motor unit firing rate. The firing rate of later recruited, high-threshold motor units declined following the 2-sec EO but was maintained following 2sec CL (P < 0.05), whereas MUFR for all motor units were maintained for both loading types following 4-sec extension phases. MVC and rate of force development where maintained following both EO and CL and 2 and 4 sec phases. This study demonstrates a slower firing rate of high-threshold motor units following fast eccentric overload while MVC was maintained. This suggests that there was a neuromuscular stimulus without cost to the force-generating capacity of the knee extensors. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Cognitive processing load during listening is reduced more by decreasing voice similarity than by increasing spatial separation between target and masker speech.

PubMed

Zekveld, Adriana A; Rudner, Mary; Kramer, Sophia E; Lyzenga, Johannes; Rönnberg, Jerker

2014-01-01

We investigated changes in speech recognition and cognitive processing load due to the masking release attributable to decreasing similarity between target and masker speech. This was achieved by using masker voices with either the same (female) gender as the target speech or different gender (male) and/or by spatially separating the target and masker speech using HRTFs. We assessed the relation between the signal-to-noise ratio required for 50% sentence intelligibility, the pupil response and cognitive abilities. We hypothesized that the pupil response, a measure of cognitive processing load, would be larger for co-located maskers and for same-gender compared to different-gender maskers. We further expected that better cognitive abilities would be associated with better speech perception and larger pupil responses as the allocation of larger capacity may result in more intense mental processing. In line with previous studies, the performance benefit from different-gender compared to same-gender maskers was larger for co-located masker signals. The performance benefit of spatially-separated maskers was larger for same-gender maskers. The pupil response was larger for same-gender than for different-gender maskers, but was not reduced by spatial separation. We observed associations between better perception performance and better working memory, better information updating, and better executive abilities when applying no corrections for multiple comparisons. The pupil response was not associated with cognitive abilities. Thus, although both gender and location differences between target and masker facilitate speech perception, only gender differences lower cognitive processing load. Presenting a more dissimilar masker may facilitate target-masker separation at a later (cognitive) processing stage than increasing the spatial separation between the target and masker. The pupil response provides information about speech perception that complements intelligibility data.

Cognitive processing load during listening is reduced more by decreasing voice similarity than by increasing spatial separation between target and masker speech

PubMed Central

Zekveld, Adriana A.; Rudner, Mary; Kramer, Sophia E.; Lyzenga, Johannes; Rönnberg, Jerker

2014-01-01

We investigated changes in speech recognition and cognitive processing load due to the masking release attributable to decreasing similarity between target and masker speech. This was achieved by using masker voices with either the same (female) gender as the target speech or different gender (male) and/or by spatially separating the target and masker speech using HRTFs. We assessed the relation between the signal-to-noise ratio required for 50% sentence intelligibility, the pupil response and cognitive abilities. We hypothesized that the pupil response, a measure of cognitive processing load, would be larger for co-located maskers and for same-gender compared to different-gender maskers. We further expected that better cognitive abilities would be associated with better speech perception and larger pupil responses as the allocation of larger capacity may result in more intense mental processing. In line with previous studies, the performance benefit from different-gender compared to same-gender maskers was larger for co-located masker signals. The performance benefit of spatially-separated maskers was larger for same-gender maskers. The pupil response was larger for same-gender than for different-gender maskers, but was not reduced by spatial separation. We observed associations between better perception performance and better working memory, better information updating, and better executive abilities when applying no corrections for multiple comparisons. The pupil response was not associated with cognitive abilities. Thus, although both gender and location differences between target and masker facilitate speech perception, only gender differences lower cognitive processing load. Presenting a more dissimilar masker may facilitate target-masker separation at a later (cognitive) processing stage than increasing the spatial separation between the target and masker. The pupil response provides information about speech perception that complements intelligibility data. PMID:24808818

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. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

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.

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…

Reaction times of normal listeners to laryngeal, alaryngeal, and synthetic speech.

PubMed

Evitts, Paul M; Searl, Jeff

2006-12-01

The purpose of this study was to compare listener processing demands when decoding alaryngeal compared to laryngeal speech. Fifty-six listeners were presented with single words produced by 1 proficient speaker from 5 different modes of speech: normal, tracheosophageal (TE), esophageal (ES), electrolaryngeal (EL), and synthetic speech (SS). Cognitive processing load was indexed by listener reaction time (RT). To account for significant durational differences among the modes of speech, an RT ratio was calculated (stimulus duration divided by RT). Results indicated that the cognitive processing load was greater for ES and EL relative to normal speech. TE and normal speech did not differ in terms of RT ratio, suggesting fairly comparable cognitive demands placed on the listener. SS required greater cognitive processing load than normal and alaryngeal speech. The results are discussed relative to alaryngeal speech intelligibility and the role of the listener. Potential clinical applications and directions for future research are also presented.

A novel indirect method for capturing involuntary musical imagery under varying cognitive load.

PubMed

Floridou, Georgia A; Williamson, Victoria J; Stewart, Lauren

2017-11-01

Involuntary musical imagery (INMI), i.e the internal experience of a repetitive musical fragment, is one of the most ubiquitous forms of spontaneous cognition. Findings regarding the relationship between INMI and cognitive load are conflicting. In the present study, 200 participants watched and evaluated two non-dialogue, music-only film trailers. Subsequently, they either closed their eyes for 5 min (baseline), or engaged in one of three dot tasks of varying challenge and attentional demand (low, medium, and high cognitive load). Finally, they completed a novel "Mind Activity Questionnaire", which allows for indirect INMI sampling rather than direct questioning. The same questionnaire was completed 24 hours later. Overall, a significant negative linear trend was found. At baseline, 65% of people reported experiencing INMI. This rate decreased to 32.5% in the low load condition with further reductions observed in the medium and high conditions, which did not differ significantly from each other. INMI frequency and duration followed the same pattern as the induction rates. In the 24-hour follow-up, 21% of participants reported INMI experiences. This study supports the hypothesis that INMI occurrence, frequency, and duration relate to spare cognitive capacity and demonstrates an ecologically valid laboratory paradigm for covertly inducing and documenting INMI experiences.

Effects of reverberation time on the cognitive load in speech communication: theoretical considerations.

PubMed

Kjellberg, A

2004-01-01

The paper presents a theoretical analysis of possible effects of reverberation time on the cognitive load in speech communication. Speech comprehension requires not only phonological processing of the spoken words. Simultaneously, this information must be further processed and stored. All this processing takes place in the working memory, which has a limited processing capacity. The more resources that are allocated to word identification, the fewer resources are therefore left for the further processing and storing of the information. Reverberation conditions that allow the identification of almost all words may therefore still interfere with speech comprehension and memory storing. These problems are likely to be especially serious in situations where speech has to be followed continuously for a long time. An unfavourable reverberation time (RT) then could contribute to the development of cognitive fatigue, which means that working memory resources are gradually reduced. RT may also affect the cognitive load in two other ways: RT may change the distracting effects of a sound and a person's mood. Both effects could influence the cognitive load of a listener. It is argued that we need studies of RT effects in realistic long-lasting listening situations to better understand the effect of RT on speech communication. Furthermore, the effect of RT on distraction and mood need to be better understood.

The effects of concurrent cognitive load on phonological processing in adults who stutter.

PubMed

Jones, Robin M; Fox, Robert A; Jacewicz, Ewa

2012-12-01

To determine whether phonological processing in adults who stutter (AWS) is disrupted by increased amounts of cognitive load in a concurrent attention-demanding task. Nine AWS and 9 adults who do not stutter (AWNS) participated. Using a dual-task paradigm, the authors presented word pairs for rhyme judgments and, concurrently, letter strings for memory recall. The rhyme judgment task manipulated rhyming type (rhyming/nonrhyming) and orthographic representation (similar/dissimilar). The memory recall task varied stimulus complexity (no letters, 3 letters, 5 letters). Rhyme judgment accuracy and reaction time (RT) were used to assess phonological processing, and letter recall accuracy was used to measure memory recall. For rhyme judgments, AWS were as accurate as AWNS, and the increase in the cognitive load did not affect rhyme judgment accuracy of either group. Significant group differences were found in RTs (delays by AWS were 241 ms greater). RTs of AWS were also slower in the most demanding rhyme condition and varied with the complexity of the memory task. Accuracy of letter recall of AWS was comparatively worse in the most demanding 5-letter condition. Phonological and cognitive processing of AWS is more vulnerable to disruptions caused by increased amounts of cognitive load in concurrent attention-demanding tasks.

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

PubMed

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

2017-03-16

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

Evaluation of cognitive load and emotional states during multidisciplinary critical care simulation sessions.

PubMed

Pawar, Swapnil; Jacques, Theresa; Deshpande, Kush; Pusapati, Raju; Meguerdichian, Michael J

2018-04-01

The simulation in critical care setting involves a heterogeneous group of participants with varied background and experience. Measuring the impacts of simulation on emotional state and cognitive load in this setting is not often performed. The feasibility of such measurement in the critical care setting needs further exploration. Medical and nursing staff with varying levels of experience from a tertiary intensive care unit participated in a standardised clinical simulation scenario. The emotional state of each participant was assessed before and after completion of the scenario using a validated eight-item scale containing bipolar oppositional descriptors of emotion. The cognitive load of each participant was assessed after the completion of the scenario using a validated subjective rating tool. A total of 103 medical and nursing staff participated in the study. The participants felt more relaxed (-0.28±1.15 vs 0.14±1, P<0.005; d=0.39), excited (0.25±0.89 vs 0.55±0.92, P<0.005, d=0.35) and alert (0.85±0.87 vs 1.28±0.73, P<0.00001, d=0.54) following simulation. There was no difference in the mean scores for the remaining five items. The mean cognitive load for all participants was 6.67±1.41. There was no significant difference in the cognitive loads among medical staff versus nursing staff (6.61±2.3 vs 6.62±1.7; P>0.05). A well-designed complex high fidelity critical care simulation scenario can be evaluated to identify the relative cognitive load of the participants' experience and their emotional state. The movement of learners emotionally from a more negative state to a positive state suggests that simulation can be an effective tool for improved knowledge transfer and offers more opportunity for dynamic thinking.

Blur Detection is Unaffected by Cognitive Load.

PubMed

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

2014-03-01

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 cognitive load produced by the N -back task.

The Preservation of Cued Recall in the Acute Mentally Fatigued State: A Randomised Crossover Study.

PubMed

Flindall, Ian Richard; Leff, Daniel Richard; Pucks, Neysan; Sugden, Colin; Darzi, Ara

2016-01-01

The objective of this study is to investigate the impact of acute mental fatigue on the recall of clinical information in the non-sleep-deprived state. Acute mental fatigue in the non-sleep-deprived subject is rarely studied in the medical workforce. Patient handover has been highlighted as an area of high risk especially in fatigued subjects. This study evaluates the deterioration in recall of clinical information over 2 h with cognitively demanding work in non-sleep-deprived subjects. A randomised crossover study involving twenty medical students assessed free (presentation) and cued (MCQ) recall of clinical case histories at 0 and 2 h under low and high cognitive load using the N-Back task. Acute mental fatigue was assessed through the Visual Analogue Scale, Stanford Scale and NASA-TLX Mental Workload Rating Scale. Free recall is significantly impaired by increased cognitive load (p < 0.05) with subjects demonstrating perceived mental fatigue during the high cognitive load assessment. There was no significant difference in the amount of information retrieved by cued recall under high and low cognitive load conditions (p = 1). This study demonstrates the loss of clinical information over a short time period involving a mentally fatiguing, high cognitive load task. Free recall for the handover of clinical information is unreliable. Memory cues maintain recall of clinical information. This study provides evidence towards the requirement for standardisation of a structured patient handover. The use of memory cues (involving recognition memory and cued recall methodology) would be beneficial in a handover checklist to aid recall of clinical information and supports evidence for their adoption into clinical practice.

Working memory maintenance is sufficient to reduce state anxiety.

PubMed

Balderston, Nicholas L; Quispe-Escudero, David; Hale, Elizabeth; Davis, Andrew; O'Connell, Katherine; Ernst, Monique; Grillon, Christian

2016-11-01

According to the attentional control theory (ACT) proposed by Eysenck and colleagues, anxiety interferes with cognitive processing by prioritizing bottom-up attentional processes over top-down attentional processes, leading to competition for access to limited resources in working memory, particularly the central executive (Eysenck, Derakshan, Santos, & Calvo, ). However, previous research using the n-back working memory task suggests that working memory load also reduces state anxiety. Assuming that similar mechanisms underlie the effect of anxiety on cognition, and the effect of cognition on anxiety, one possible implication of the ACT would suggest that the reduction of state anxiety with increasing working memory load is driven by activation of central executive attentional control processes. We tested this hypothesis using the Sternberg working memory paradigm, where maintenance processes can be isolated from central executive processes (Altamura et al., ; Sternberg, ). Consistent with the n-back results, subjects showed decreased state anxiety during the maintenance period of high-load trials relative to low-load trials, suggesting that maintenance processes alone are sufficient to achieve this state anxiety reduction. Given that the Sternberg task does not require central executive engagement, these results are not consistent with an implication of the ACT where the cognition/anxiety relationship and anxiety/cognition relationship are mediated by similar central executive mechanisms. Instead, we propose an extension of the ACT such that engaging working memory maintenance suppresses state anxiety in a load-dependent manner. Furthermore, we hypothesize that the efficacy of this effect may moderate the effect of trait anxiety on cognition. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

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

PubMed

Dan, Alex; Reiner, Miriam

2017-12-01

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. Copyright © 2016 Elsevier B.V. All rights reserved.

Attention Measures of Accuracy, Variability, and Fatigue Detect Early Response to Donepezil in Alzheimer's Disease: A Randomized, Double-blind, Placebo-Controlled Pilot Trial.

PubMed

Vila-Castelar, Clara; Ly, Jenny J; Kaplan, Lillian; Van Dyk, Kathleen; Berger, Jeffrey T; Macina, Lucy O; Stewart, Jennifer L; Foldi, Nancy S

2018-04-09

Donepezil is widely used to treat Alzheimer's disease (AD), but detecting early response remains challenging for clinicians. Acetylcholine is known to directly modulate attention, particularly under high cognitive conditions, but no studies to date test whether measures of attention under high load can detect early effects of donepezil. We hypothesized that load-dependent attention tasks are sensitive to short-term treatment effects of donepezil, while global and other domain-specific cognitive measures are not. This longitudinal, randomized, double-blind, placebo-controlled pilot trial (ClinicalTrials.gov Identifier: NCT03073876) evaluated 23 participants newly diagnosed with AD initiating de novo donepezil treatment (5 mg). After baseline assessment, participants were randomized into Drug (n = 12) or Placebo (n = 11) groups, and retested after approximately 6 weeks. Cognitive assessment included: (a) attention tasks (Foreperiod Effect, Attentional Blink, and Covert Orienting tasks) measuring processing speed, top-down accuracy, orienting, intra-individual variability, and fatigue; (b) global measures (Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental Status Examination, Dementia Rating Scale); and (c) domain-specific measures (memory, language, visuospatial, and executive function). The Drug but not the Placebo group showed benefits of treatment at high-load measures by preserving top-down accuracy, improving intra-individual variability, and averting fatigue. In contrast, other global or cognitive domain-specific measures could not detect treatment effects over the same treatment interval. The pilot-study suggests that attention measures targeting accuracy, variability, and fatigue under high-load conditions could be sensitive to short-term cholinergic treatment. Given the central role of acetylcholine in attentional function, load-dependent attentional measures may be valuable cognitive markers of early treatment response.

Load-Dependent Interference of Deep Brain Stimulation of the Subthalamic Nucleus with Switching from Automatic to Controlled Processing During Random Number Generation in Parkinson's Disease.

PubMed

Williams, Isobel Anne; Wilkinson, Leonora; Limousin, Patricia; Jahanshahi, Marjan

2015-01-01

Deep brain stimulation of the subthalamic nucleus (STN DBS) ameliorates the motor symptoms of Parkinson's disease (PD). However, some aspects of executive control are impaired with STN DBS. We tested the prediction that (i) STN DBS interferes with switching from automatic to controlled processing during fast-paced random number generation (RNG) (ii) STN DBS-induced cognitive control changes are load-dependent. Fifteen PD patients with bilateral STN DBS performed paced-RNG, under three levels of cognitive load synchronised with a pacing stimulus presented at 1, 0.5 and 0.33 Hz (faster rates require greater cognitive control), with DBS on or off. Measures of output randomness were calculated. Countscore 1 (CS1) indicates habitual counting in steps of one (CS1). Countscore 2 (CS2) indicates a more controlled strategy of counting in twos. The fastest rate was associated with an increased CS1 score with STN DBS on compared to off. At the slowest rate, patients had higher CS2 scores with DBS off than on, such that the differences between CS1 and CS2 scores disappeared. We provide evidence for a load-dependent effect of STN DBS on paced RNG in PD. Patients could switch to more controlled RNG strategies during conditions of low cognitive load at slower rates only when the STN stimulators were off, but when STN stimulation was on, they engaged in more automatic habitual counting under increased cognitive load. These findings are consistent with the proposal that the STN implements a switch signal from the medial frontal cortex which enables a shift from automatic to controlled processing.

Load-Dependent Interference of Deep Brain Stimulation of the Subthalamic Nucleus with Switching from Automatic to Controlled Processing During Random Number Generation in Parkinson’s Disease

PubMed Central

Williams, Isobel Anne; Wilkinson, Leonora; Limousin, Patricia; Jahanshahi, Marjan

2015-01-01

Background: Deep brain stimulation of the subthalamic nucleus (STN DBS) ameliorates the motor symptoms of Parkinson’s disease (PD). However, some aspects of executive control are impaired with STN DBS. Objective: We tested the prediction that (i) STN DBS interferes with switching from automatic to controlled processing during fast-paced random number generation (RNG) (ii) STN DBS-induced cognitive control changes are load-dependent. Methods: Fifteen PD patients with bilateral STN DBS performed paced-RNG, under three levels of cognitive load synchronised with a pacing stimulus presented at 1, 0.5 and 0.33 Hz (faster rates require greater cognitive control), with DBS on or off. Measures of output randomness were calculated. Countscore 1 (CS1) indicates habitual counting in steps of one (CS1). Countscore 2 (CS2) indicates a more controlled strategy of counting in twos. Results: The fastest rate was associated with an increased CS1 score with STN DBS on compared to off. At the slowest rate, patients had higher CS2 scores with DBS off than on, such that the differences between CS1 and CS2 scores disappeared. Conclusions: We provide evidence for a load-dependent effect of STN DBS on paced RNG in PD. Patients could switch to more controlled RNG strategies during conditions of low cognitive load at slower rates only when the STN stimulators were off, but when STN stimulation was on, they engaged in more automatic habitual counting under increased cognitive load. These findings are consistent with the proposal that the STN implements a switch signal from the medial frontal cortex which enables a shift from automatic to controlled processing. PMID:25720447

Does the Cambridge Automated Neuropsychological Test Battery (CANTAB) Distinguish Between Cognitive Domains in Healthy Older Adults?

PubMed

Lenehan, Megan E; Summers, Mathew J; Saunders, Nichole L; Summers, Jeffery J; Vickers, James C

2016-04-01

The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a semiautomated computer interface for assessing cognitive function. We examined whether CANTAB tests measured specific cognitive functions, using established neuropsychological tests as a reference point. A sample of 500 healthy older (M = 60.28 years, SD = 6.75) participants in the Tasmanian Healthy Brain Project completed battery of CANTAB subtests and standard paper-based neuropsychological tests. Confirmatory factor analysis identified four factors: processing speed, verbal ability, episodic memory, and working memory. However, CANTAB tests did not consistently load onto the cognitive domain factors derived from traditional measures of the same function. These results indicate that five of the six CANTAB subtests examined did not load onto single cognitive functions. These CANTAB tests may lack the sensitivity to measure discrete cognitive functions in healthy populations or may measure other cognitive domains not included in the traditional neuropsychological battery. © The Author(s) 2015.

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

A reverse order interview does not aid deception detection regarding intentions

PubMed Central

Fenn, Elise; McGuire, Mollie; Langben, Sara; Blandón-Gitlin, Iris

2015-01-01

Promising recent research suggests that more cognitively demanding interviews improve deception detection accuracy. Would these cognitively demanding techniques work in the same way when discriminating between true and false future intentions? In Experiment 1 participants planned to complete a task, but instead were intercepted and interviewed about their intentions. Participants lied or told the truth, and were subjected to high (reverse order) or low (sequential order) cognitive load interviews. Third-party observers watched these interviews and indicated whether they thought the person was lying or telling the truth. Subjecting participants to a reverse compared to sequential interview increased the misidentification rate and the appearance of cognitive load in truth tellers. People lying about false intentions were not better identified. In Experiment 2, a second set of third-party observers rated behavioral cues. Consistent with Experiment 1, truth tellers, but not liars, exhibited more behaviors associated with lying and fewer behaviors associated with truth telling in the reverse than sequential interview. Together these results suggest that certain cognitively demanding interviews may be less useful when interviewing to detect false intentions. Explaining a true intention while under higher cognitive demand places truth tellers at risk of being misclassified. There may be such a thing as too much cognitive load induced by certain techniques PMID:26379610

A reverse order interview does not aid deception detection regarding intentions.

PubMed

Fenn, Elise; McGuire, Mollie; Langben, Sara; Blandón-Gitlin, Iris

2015-01-01

Promising recent research suggests that more cognitively demanding interviews improve deception detection accuracy. Would these cognitively demanding techniques work in the same way when discriminating between true and false future intentions? In Experiment 1 participants planned to complete a task, but instead were intercepted and interviewed about their intentions. Participants lied or told the truth, and were subjected to high (reverse order) or low (sequential order) cognitive load interviews. Third-party observers watched these interviews and indicated whether they thought the person was lying or telling the truth. Subjecting participants to a reverse compared to sequential interview increased the misidentification rate and the appearance of cognitive load in truth tellers. People lying about false intentions were not better identified. In Experiment 2, a second set of third-party observers rated behavioral cues. Consistent with Experiment 1, truth tellers, but not liars, exhibited more behaviors associated with lying and fewer behaviors associated with truth telling in the reverse than sequential interview. Together these results suggest that certain cognitively demanding interviews may be less useful when interviewing to detect false intentions. Explaining a true intention while under higher cognitive demand places truth tellers at risk of being misclassified. There may be such a thing as too much cognitive load induced by certain techniques.

Thrive or overload? The effect of task complexity on novices' simulation-based learning.

PubMed

Haji, Faizal A; Cheung, Jeffrey J H; Woods, Nicole; Regehr, Glenn; de Ribaupierre, Sandrine; Dubrowski, Adam

2016-09-01

Fidelity is widely viewed as an important element of simulation instructional design based on its purported relationship with transfer of learning. However, higher levels of fidelity may increase task complexity to a point at which novices' cognitive resources become overloaded. In this experiment, we investigate the effects of variations in task complexity on novices' cognitive load and learning during simulation-based procedural skills training. Thirty-eight medical students were randomly assigned to simulation training on a simple or complex lumbar puncture (LP) task. Participants completed four practice trials on this task (skill acquisition). After 10 days of rest, all participants completed one additional trial on their assigned task (retention) and one trial on a 'very complex' simulation designed to be similar to the complex task (transfer). We assessed LP performance and cognitive load on each trial using multiple measures. In both groups, LP performance improved significantly during skill acquisition (p ≤ 0.047, f = 0.29-0.96) and was maintained at retention. The simple task group demonstrated superior performance compared with the complex task group throughout these phases (p ≤ 0.002, d = 1.13-2.31). Cognitive load declined significantly in the simple task group (p < 0.009, f = 0.48-0.76), but not in the complex task group during skill acquisition, and remained lower at retention (p ≤ 0.024, d = 0.78-1.39). Between retention and transfer, LP performance declined and cognitive load increased in the simple task group, whereas both remained stable in the complex task group. At transfer, no group differences were observed in LP performance and cognitive load, except that the simple task group made significantly fewer breaches of sterility (p = 0.023, d = 0.80). Reduced task complexity was associated with superior LP performance and lower cognitive load during skill acquisition and retention, but mixed results on transfer to a more complex task. These results indicate that task complexity is an important factor that may mediate (via cognitive overload) the relationship between instructional design elements (e.g. fidelity) and simulation-based learning outcomes. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

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

PubMed

Zimmerman, Frederick J; Shimoga, Sandhya V

2014-04-10

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. 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. 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). Televised food advertising has strong effects on individual food choice, and these effects are magnified when individuals are cognitively occupied by other tasks.

The Effects of Concurrent Cognitive Load on Phonological Processing in Adults Who Stutter

ERIC Educational Resources Information Center

Jones, Robin M.; Fox, Robert A.; Jacewicz, Ewa

2012-01-01

Purpose: To determine whether phonological processing in adults who stutter (AWS) is disrupted by increased amounts of cognitive load in a concurrent attention-demanding task. Method: Nine AWS and 9 adults who do not stutter (AWNS) participated. Using a dual-task paradigm, the authors presented word pairs for rhyme judgments and, concurrently,…

Evaluating the Benefits of Displaying Word Prediction Lists on a Personal Digital Assistant at the Keyboard Level

ERIC Educational Resources Information Center

Tam, Cynthia; Wells, David

2009-01-01

Visual-cognitive loads influence the effectiveness of word prediction technology. Adjusting parameters of word prediction programs can lessen visual-cognitive loads. This study evaluated the benefits of WordQ word prediction software for users' performance when the prediction window was moved to a personal digital assistant (PDA) device placed at…

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…

Short vs. Long: Cognitive Load, Retention and Changing Class Structures

ERIC Educational Resources Information Center

Sheridan, Brandon; Smith, Ben; Pleggenkuhle-Miles, Erin

2017-01-01

University class structure is changing. To accommodate working students, programmes are increasing their offerings of long night classes--some lasting as long as six hours. While these long classes may be more convenient for students, they have unintended consequences as a result of cognitive load. Using a panel of 124 students (372 observations)…

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…

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…

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…

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…

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,…

Effectiveness of Different Pinyin Presentation Formats in Learning Chinese Characters: A Cognitive Load Perspective

ERIC Educational Resources Information Center

Lee, Chee Ha; Kalyuga, Slava

2011-01-01

This article reports the results of an experiment designed to investigate the effectiveness of pinyin (a phonic transcription system) in learning vocabulary of Chinese as a second language from the perspective of cognitive load theory. In the reported experiment, the learning effects of the vertical and horizontal layouts of characters, pinyin,…

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…

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…

Applying Cognitive Load Theory Principles to Library Instructional Guidance

ERIC Educational Resources Information Center

Pickens, Kathleen E.

2017-01-01

If the goal of library instructional guidance is to provide students with the knowledge needed to acquire new skills in order to accomplish their learning objectives, then it is prudent to consider factors that impact learning. Cognitive load theory addresses several of these factors and is applicable to a wide-range of instructional devices used…

A Test of Attention Control Theory in Public Speaking: Cognitive Load Influences the Relationship between State Anxiety and Verbal Production

ERIC Educational Resources Information Center

King, Paul E.; Finn, Amber N.

2017-01-01

This study investigated the relationship between public-speaking state anxiety (PSA) and verbal communication performance when delivering a speech. In Study 1, participants delivered an extemporaneous five-minute classroom speech behind a lectern, and in Study 2, to increase cognitive load, participants delivered an extemporaneous five-minute…

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…

Teaching Domain-Specific Skills before Peer Assessment Skills Is Superior to Teaching Them Simultaneously

ERIC Educational Resources Information Center

van Zundert, M. J.; Konings, K. D.; Sluijsmans, D. M. A.; van Merrienboer, J.J.G.

2012-01-01

Instruction in peer assessment of complex task performance may cause high cognitive load, impairing learning. A stepwise instructional strategy aimed at reducing cognitive load was investigated by comparing it with a combined instructional strategy in an experiment with 128 secondary school students (mean age 14.0 years; 45.2% male) with the…

Pupillometry as a Tool to Study Expertise in Medicine

ERIC Educational Resources Information Center

Szulewski, Adam; Kelton, Danielle; Howes, Daniel

2017-01-01

Background: Pupillometry has been studied as a physiological marker for quantifying cognitive load since the early 1960s. It has been established that small changes in pupillary size can provide an index of the cognitive load of an individual as he/she performs a mental task. The utility of pupillometry as a measure of expertise is less well…

Learning Declarative and Procedural Knowledge via Video Lectures: Cognitive Load and Learning Effectiveness

ERIC Educational Resources Information Center

Hong, Jianzhong; Pi, Zhongling; Yang, Jiumin

2018-01-01

Video lectures are being widely used in online and blended learning classes worldwide, and their learning effectiveness is becoming a focus of many educators and researchers. This study examined the cognitive load and learning effectiveness of video lectures in terms of the type of knowledge being taught (declarative or procedural) and instructor…

Affective Overload: The Effect of Emotive Visual Stimuli on Target Vocabulary Retrieval

ERIC Educational Resources Information Center

Çetin, Yakup; Griffiths, Carol; Özel, Zeynep Ebrar Yetkiner; Kinay, Hüseyin

2016-01-01

There has been considerable interest in cognitive load in recent years, but the effect of affective load and its relationship to mental functioning has not received as much attention. In order to investigate the effects of affective stimuli on cognitive function as manifest in the ability to remember foreign language vocabulary, two groups of…

Effects of Presentation Modes on Mobile-Assisted Vocabulary Learning and Cognitive Load

ERIC Educational Resources Information Center

Lin, Chih-Cheng; Yu, Ya-Chuan

2017-01-01

Previous studies of multimedia presentations have determined the effects of the combination of text and pictures on vocabulary learning, but not those of the sound of new words. This study was intended to confirm those previous findings from the integration of mobile technologies and the approach of cognitive load. It adopted a within-subjects…

Geothermal solute flux monitoring and the source and fate of solutes in the Snake River, Yellowstone National Park, WY

USGS Publications Warehouse

McCleskey, R. Blaine; Lowenstern, Jacob B.; Schaper, Jonas; Nordstrom, D. Kirk; Heasler, Henry P.; Mahony, Dan

2016-01-01

The combined geothermal discharge from over 10,000 features in Yellowstone National Park (YNP) can be can be estimated from the Cl flux in the Madison, Yellowstone, Falls, and Snake Rivers. Over the last 30 years, the Cl flux in YNP Rivers has been calculated using discharge measurements and Cl concentrations determined in discrete water samples and it has been determined that approximately 12% of the Cl flux exiting YNP is from the Snake River. The relationship between electrical conductivity and concentrations of Cl and other geothermal solutes was quantified at a monitoring site located downstream from the thermal inputs in the Snake River. Beginning in 2012, continuous (15 min) electrical conductivity measurements have been made at the monitoring site. Combining continuous electrical conductivity and discharge data, the Cl and other geothermal solute fluxes were determined. The 2013–2015 Cl fluxes (5.3–5.8 kt/yr) determined using electrical conductivity are comparable to historical data. In addition, synoptic water samples and discharge data were obtained from sites along the Snake River under low-flow conditions of September 2014. The synoptic water study extended 17 km upstream from the monitoring site. Surface inflows were sampled to identify sources and to quantify solute loading. The Lewis River was the primary source of Cl, Na, K, Cl, SiO2, Rb, and As loads (50–80%) in the Snake River. The largest source of SO4 was from the upper Snake River (50%). Most of the Ca and Mg (50–55%) originate from the Snake Hot Springs. Chloride, Ca, Mg, Na, K, SiO2, F, HCO3, SO4, B, Li, Rb, and As behave conservatively in the Snake River, and therefore correlate well with conductivity (R2 ≥ 0.97).

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.

Degradation forecast for PEMFC cathode-catalysts under cyclic loads

NASA Astrophysics Data System (ADS)

Moein-Jahromi, M.; Kermani, M. J.; Movahed, S.

2017-08-01

Degradation of Fuel Cell (FC) components under cyclic loads is one of the biggest bottlenecks in FC commercialization. In this paper, a novel experimental based algorithm is presented to predict the Catalyst Layer (CL) performance loss during cyclic load. The algorithm consists of two models namely Models 1 and 2. The Model 1 calculates the Electro-Chemical Surface Area (ECSA) and agglomerate size (e.g. agglomerate radius, rt,agg) for the catalyst layer under cyclic load. The Model 2 is the already-existing model from our earlier studies that computes catalyst performance with fixed structural parameters. Combinations of these two Models predict the CL performance under an arbitrary cyclic load. A set of parametric/sensitivity studies is performed to investigate the effects of operating parameters on the percentage of Voltage Degradation Rate (VDR%) with rank 1 for the most influential one. Amongst the considered parameters (such as: temperature, relative humidity, pressure, minimum and maximum voltage of the cyclic load), the results show that temperature and pressure have the most and the least influences on the VDR%, respectively. So that, increase of temperature from 60 °C to 80 °C leads to over 20% VDR intensification, the VDR will also reduce 1.41% by increasing pressure from 2 atm to 4 atm.

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.

Battling the challenges of training nurses to use information systems through theory-based training material design.

PubMed

Galani, Malatsi; Yu, Ping; Paas, Fred; Chandler, Paul

2014-01-01

The attempts to train nurses to effectively use information systems have had mixed results. One problem is that training materials are not adequately designed to guide trainees to gradually learn to use a system without experiencing a heavy cognitive load. This is because training design often does not take into consideration a learner's cognitive ability to absorb new information in a short training period. Given the high cost and difficulty of organising training in healthcare organisations, there is an urgent need for information system trainers to be aware of how cognitive overload or information overload affect a trainee's capability to acquire new knowledge and skills, and what instructional techniques can be used to facilitate effective learning. This paper introduces the concept of cognitive load and how it affects nurses when learning to use a new health information system. This is followed by the relevant strategies for instructional design, underpinned by the principles of cognitive load theory, which may be helpful for the development of effective instructional materials and activities for training nurses to use information systems.

The effects of working memory load and attention refocusing on delay discounting rates in alcohol use disorder with comorbid antisocial personality disorder.

PubMed

Gunn, Rachel L; Gerst, Kyle R; Lake, Allison J; Finn, Peter R

2018-02-01

Executive working memory capacity (eWMC) is central to adaptive decision-making. Research has revealed reduced eWMC and higher rates of impulsive decision making in individuals with alcohol use disorders (AUDs: DSM-IV Alcohol Dependence of Alcohol Abuse) and antisocial psychopathology (AP). Recent work has shown that placing a load on working memory (WM) further increases impulsive decision making on the delay discounting (DD) task in those with AUDs and AP. The current study examined the effects of an attention refocusing manipulation to offset the effects of this WM-load on DD rates in control subjects, those with AUDs without AP, and AUDs with AP (AUD-AP). Results revealed that 1) the AUD-AP group had higher DD rates (i.e., more impulsive decision-making) than the AUD group, followed by controls, and 2) attention refocusing after a load is placed on WM was associated with lower DD rates compared to the load without refocusing in both AUD groups, but not controls. Results suggest that refocusing attention after a cognitive load may be an effective cognitive strategy for reducing the impulsivity-enhancing effects of cognitive load on decision making in individuals with AUDs and AP. Copyright © 2017 Elsevier Inc. All rights reserved.

Adsorption equilibrium and kinetics of monomer-dimer monoclonal antibody mixtures on a cation exchange resin.

PubMed

Reck, Jason M; Pabst, Timothy M; Hunter, Alan K; Wang, Xiangyang; Carta, Giorgio

2015-07-10

Adsorption equilibrium and kinetics are determined for a monoclonal antibody (mAb) monomer and dimer species, individually and in mixtures, on a macroporous cation exchange resin both under the dilute limit of salt gradient elution chromatography and at high protein loads and low salt based on batch adsorption equilibrium and confocal laser scanning microscopy (CLSM) experiments. In the dilute limit and weak binding conditions, the dimer/monomer selectivity in 10mM phosphate at pH 7 varies between 8.7 and 2.3 decreasing with salt concentration in the range of 170-230mM NaCl. At high protein loads and strong binding conditions (0-60mM NaCl), the selectivity in the same buffer is near unity with no NaCl added, but increases gradually with salt concentration reaching high values between 2 and 15 with 60mM added NaCl. For these conditions, the two-component adsorption kinetics is controlled by pore diffusion and is predicted approximately by a dual shrinking core model using parameters based on single component equilibrium and kinetics measurements. Copyright © 2015 Elsevier B.V. All rights reserved.

LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

DOEpatents

Ko, Suk M.

1980-01-01

This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

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

PubMed

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

2017-07-01

Longitudinal research indicates that cognitive load dual-task gait assessment is predictive of cognitive decline and thus might provide a sensitive measure to screen for mild cognitive impairment (MCI). However, research among older adults being clinically evaluated for cognitive concerns, a defining feature of MCI, is lacking. The present study investigated the effect of performing a cognitive task on normal walking speed in patients presenting to a memory clinic with cognitive complaints. Sixty-one patients with a mean age of 68 years underwent comprehensive neuropsychological testing, clinical interview, and gait speed (simple- and dual-task conditions) assessments. Thirty-four of the 61 patients met criteria for MCI. Repeated measure analyses of covariance revealed that greater age and MCI both significantly associated with slower gait speed, ps<.05. Follow-up analysis indicated that the MCI group had significantly slower dual-task gait speed but did not differ in simple-gait speed. Multivariate linear regression across groups found that executive attention performance accounted for 27.4% of the variance in dual-task gait speed beyond relevant demographic and health risk factors. The present study increases the external validity of dual-task gait assessment of MCI. Differences in dual-task gait speed appears to be largely attributable to executive attention processes. These findings have clinical implications as they demonstrate expected patterns of gait-brain behavior relationships in response to a cognitive dual task within a clinically representative population. Cognitive load dual-task gait assessment may provide a cost efficient and sensitive measure to detect older adults at high risk of a dementia disorder. (JINS, 2017, 23, 493-501).

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

Mechanism of chloride-dependent release of Ca2+ in the sarcoplasmic reticulum of rabbit skeletal muscle.

PubMed Central

Sukhareva, M; Morrissette, J; Coronado, R

1994-01-01

We investigated the effect of Cl- on the Ca2+ permeability of rabbit skeletal muscle junctional sarcoplasmic reticulum (SR) using 45Ca2+ fluxes and single channel recordings. In 45Ca2+ efflux experiments, the lumen of the SR was passively loaded with solutions of 150 mM univalent salt containing 5 mM 45Ca2+. Release of 45Ca2+ was measured by rapid filtration in the presence of extravesicular 0.4-0.8 microM free Ca2+ and 150 mM of the same univalent salt loaded into the SR lumen. The rate of release was 5-10 times higher when the univalent salt equilibrated across the SR-contained Cl- (Tris-Cl, choline-Cl, KCl) instead of an organic anion or other halides (gluconate-, methanesulfonate-, acetate-, HEPES-, Br-, I-). Cations (K+, Tris+) could be interchanged without a significant effect on the release rate. To determine whether Cl- stimulated ryanodine receptors, we measured the stimulation of release by ATP (5 mM total) and caffeine (20 mM total) and the inhibition by Mg2+ (0.8 mM estimated free) in Cl(-)-free and Cl(-)-containing solutions. The effects of ATP, caffeine, and Mg2+ were the largest in K-gluconate and Tris-gluconate, intermediate in KCl, and notably poor or absent in choline-Cl and Tris-Cl. Procaine (10 mM) inhibited the caffeine-stimulated release measured in K-gluconate, whereas the Cl- channel blocker clofibric acid (10 mM) but not procaine inhibited the caffeine-insensitive release measured in choline-Cl. Ruthenium red (20 microM) inhibited release in all solutions. In SR fused to planar bilayers we identified a nonselective Cl- channel (PCl: PTris: PCa = 1:0.5:0.3) blocked by ruthenium red and clofibric acid but not by procaine. These conductive and pharmacological properties suggested the channel was likely to mediate Cl(-)-dependent SR Ca2+ release. The absence of a contribution of ryanodine receptors to the Cl(-)-dependent release were indicated by the lack of an effect of Cl- on the open probability of this channel, a complete block by procaine, and a stimulation rather than inhibition by clofibric acid. A plug model of Cl(-)-dependent release, whereby Cl- removed the inhibition of the nonselective channel by large anions, was formulated under the assumption that nonselective channels and ryanodine receptor channels operated separately from each other in the terminal cisternae. The remarkably large contribution of Cl- to the SR Ca2+ permeability suggested that nonselective Cl- channels may control the Ca2+ permeability of the SR in the resting muscle cell. Images FIGURE 8 FIGURE 13 PMID:7948689

Glycopolymer micelles with reducible ionic cores for hepatocytes-targeting delivery of DOX.

PubMed

Wang, Yanxia; Zhang, Xinge; Yu, Peien; Li, Chaoxing

2013-01-30

A novel galactose-decorated cross-linked micelles (cl-micelles) with ionic cores using cystamine (Cys) as a biodegradable cross-linker was prepared by using block ionomer complexes of poly(ethylene glycol)-b-poly(2-acryloxyethyl-galactose)-b-poly(acrylic acid) (PEG-b-PAEG-b-PAA) and Ca(2+) (PEG-b-PAEG-b-PAA cl-micelles/Cys). Doxorubicin (DOX) was successfully incorporated into the ionic cores of such micelles via electrostatic interactions. Proton nuclear magnetic resonance spectrum and Fourier transform infrared spectrometer indicated galactose ligands were exposed at the micellar surface. The micelles were spherical in shape, with an average size of 100nm. The in vitro release studies confirmed that DOX-loaded PEG-b-PAEG-b-PAA cl-micelles/Cys accomplished rapid drug release under reducing condition. Remarkably, PEG-b-PAEG-b-PAA cl-micelles/Cys efficiently delivered and released DOX into the cell nucleus of HepG2 cells, and the intensity of fluorescence observed in HepG2 cells was stronger than that incubated with the micelles without galactose ligands. In contrast, little fluorescence was observed in NIH3T3 cells after incubation with PEG-b-PAEG-b-PAA cl-micelles/Cys. Interestingly, cytotoxicity assays showed that DOX-loaded PEG-b-PAEG-b-PAA cl-micelles/Cys retained higher cell inhibition efficiency in HepG2 cells as compared with NIH3T3 cells, and were more potent than the micelles without galactose ligands and the micelles with non degradable cross-links. These results indicate that PEG-b-PAEG-b-PAA cl-micelles/Cys have great potential in liver tumor-targeted chemotherapy. Copyright © 2012 Elsevier B.V. All rights reserved.

Zr-doped ceria additives for enhanced PEM fuel cell durability and radical scavenger stability

DOE PAGES

Baker, Andrew M.; Williams, Stefan Thurston DuBard; Mukundan, Rangachary; ...

2017-06-06

Doped ceria compounds demonstrate excellent radical scavenging abilities and are promising additives to improve the chemical durability of polymer electrolyte membrane (PEM) fuel cells. Here in this paper, Ce 0.85Zr 0.15O 2 (CZO) nanoparticles were incorporated into the cathode catalyst layers (CLs) of PEM fuel cells (based on Nafion XL membranes containing 6.0 μg cm -2 ion-exchanged Ce) at loadings of 10 and 55 μg cm -2. When compared to a CZO-free baseline, CZO-containing membrane electrode assemblies (MEAs) demonstrated extended lifetimes during PEM chemical stability accelerated stress tests (ASTs), exhibiting reduced electrochemical gas crossover, open circuit voltage decay, and fluoridemore » emission rates. The MEA with high CZO loading (55 μg cm -2) demonstrated performance losses, which are attributed to Ce poisoning of the PEM and CL ionomer regions, which is supported by X-ray fluorescence (XRF) analysis. In the MEA with the low CZO loading (10 μg cm -2), both the beginning of life (BOL) performance and the performance after 500 hours of ASTs were nearly identical to the BOL performance of the CZO-free baseline MEA. XRF analysis of the MEA with low CZO loading reveals that the BOL PEM Ce concentrations are preserved after 1408 hours of ASTs and that Ce contents in the cathode CL are not significant enough to reduce performance. Therefore, employing a highly effective radical scavenger such as CZO, at a loading of 10 μg cm -2 in the cathode CL, dramatically mitigates degradation effects, which improves MEA chemical durability and minimizes performance losses.« less

Zr-doped ceria additives for enhanced PEM fuel cell durability and radical scavenger stability

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

Baker, Andrew M.; Williams, Stefan Thurston DuBard; Mukundan, Rangachary

Doped ceria compounds demonstrate excellent radical scavenging abilities and are promising additives to improve the chemical durability of polymer electrolyte membrane (PEM) fuel cells. Here in this paper, Ce 0.85Zr 0.15O 2 (CZO) nanoparticles were incorporated into the cathode catalyst layers (CLs) of PEM fuel cells (based on Nafion XL membranes containing 6.0 μg cm -2 ion-exchanged Ce) at loadings of 10 and 55 μg cm -2. When compared to a CZO-free baseline, CZO-containing membrane electrode assemblies (MEAs) demonstrated extended lifetimes during PEM chemical stability accelerated stress tests (ASTs), exhibiting reduced electrochemical gas crossover, open circuit voltage decay, and fluoridemore » emission rates. The MEA with high CZO loading (55 μg cm -2) demonstrated performance losses, which are attributed to Ce poisoning of the PEM and CL ionomer regions, which is supported by X-ray fluorescence (XRF) analysis. In the MEA with the low CZO loading (10 μg cm -2), both the beginning of life (BOL) performance and the performance after 500 hours of ASTs were nearly identical to the BOL performance of the CZO-free baseline MEA. XRF analysis of the MEA with low CZO loading reveals that the BOL PEM Ce concentrations are preserved after 1408 hours of ASTs and that Ce contents in the cathode CL are not significant enough to reduce performance. Therefore, employing a highly effective radical scavenger such as CZO, at a loading of 10 μg cm -2 in the cathode CL, dramatically mitigates degradation effects, which improves MEA chemical durability and minimizes performance losses.« less

Working memory load modulates the neural response to other's pain: Evidence from an ERP study.

PubMed

Cui, Fang; Zhu, Xiangru; Luo, Yuejia; Cheng, Jiaping

2017-03-22

The present study investigated the time course of processing other's pain under different conditions of working memory (WM) load. Event-related potentials (ERPs) were recorded while the participants held two digits (low WM load) or six digits (high WM load) in WM and viewed pictures that showed others who were in painful or non-painful situations. Robust WM-load×Picture interactions were found for the N2 and LPP components. In the high WM-load condition, painful pictures elicited significantly larger amplitudes than non-painful pictures. In the low WM load condition, the difference between the painful and non-painful pictures was not significant. These ERP results indicate that WM load can influence both the early automatic N2 component and late cognitive LPP component. Compared with high WM load, low WM load reduced affective arousal and emotional sharing in response to other's pain and weakened the cognitive evaluation of task irrelevant stimuli. These findings are explained from the load theory perspective. Copyright © 2017 Elsevier B.V. All rights reserved.

White matter lesions and the cholinergic deficit in aging and mild cognitive impairment.

PubMed

Richter, Nils; Michel, Anne; Onur, Oezguer A; Kracht, Lutz; Dietlein, Markus; Tittgemeyer, Marc; Neumaier, Bernd; Fink, Gereon R; Kukolja, Juraj

2017-05-01

In Alzheimer's disease (AD), white matter lesions (WMLs) are associated with an increased risk of progression from mild cognitive impairment (MCI) to dementia, while memory deficits have, at least in part, been linked to a cholinergic deficit. We investigated the relationship between WML load assessed with the Scheltens scale, cerebral acetylcholinesterase (AChE) activity measured with [ 11 C]N-methyl-4-piperidyl acetate PET, and neuropsychological performance in 17 patients with MCI due to AD and 18 cognitively normal older participants. Only periventricular, not nonperiventricular, WML load negatively correlated with AChE activity in both groups. Memory performance depended on periventricular and total WML load across groups. Crucially, AChE activity predicted memory function better than WML load, gray matter atrophy, or age. The effects of WML load on memory were fully mediated by AChE activity. Data suggest that the contribution of WML to the dysfunction of the cholinergic system in MCI due to AD depends on WML distribution. Pharmacologic studies are warranted to explore whether this influences the response to cholinergic treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

Proactive Semantic Interference is Associated with Total and Regional Abnormal Amyloid Load in Non-Demented Community-Dwelling Elders: A Preliminary Study.

PubMed

Loewenstein, David A; Greig, Maria T; Curiel, Rosie; Rodriguez, Rosemarie; Wicklund, Meredith; Barker, Warren W; Hidalgo, Jacqueline; Rosado, Marian; Duara, Ranjan

2015-12-01

To evaluate the relationship between susceptibility to proactive semantic interference (PSI) and retroactive semantic interference (RSI) and brain amyloid load in non-demented elders. 27 participants (11 cognitively normal [CN] with subjective memory complaints, 8 CN without memory complaints, and 8 with mild cognitive impairment [MCI]) underwent complete neurological and neuropsychological evaluations. Participants also received the Semantic Interference Test (SIT) and AV-45 amyloid PET imaging. High levels of association were present between total amyloid load, regional amyloid levels, and the PSI measure (in the entire sample and a subsample excluding MCI subjects). RSI and other memory measures showed much weaker associations or no associations with total and regional amyloid load. No associations between amyloid levels and non-memory performance were observed. In non-demented individuals, vulnerability to PSI was highly associated with total and regional beta-amyloid load and may be an early cognitive marker of brain pathology. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Teaching Letter Formation.

ERIC Educational Resources Information Center

Graham, Steve; Madan, Avi J.

1981-01-01

The authors describe a remedial technique for teaching letter formation to students with handwriting difficulties. The approach blends traditional procedures (modeling, physical prompts, tracing, self correction, etc.) with cognitive behavior modification principles. (CL)

Blockade of AT1 Receptors Protects the Blood–Brain Barrier and Improves Cognition in Dahl Salt-Sensitive Hypertensive Rats

PubMed Central

Pelisch, Nicolas; Hosomi, Naohisa; Ueno, Masaki; Nakano, Daisuke; Hitomi, Hirofumi; Mogi, Masaki; Shimada, Kenji; Kobori, Hiroyuki; Horiuchi, Masatsugu; Sakamoto, Haruhiko; Matsumoto, Masayasu; Kohno, Masakazu; Nishiyama, Akira

2011-01-01

BACKGROUND The present study tested the hypothesis that inappropriate activation of the brain renin–angiotensin system (RAS) contributes to the pathogenesis of blood–brain barrier (BBB) disruption and cognitive impairment during development of salt-dependent hypertension. Effects of an angiotensin II (AngII) type-1 receptor blocker (ARB), at a dose that did not reduce blood pressure, were also examined. METHODS Dahl salt-sensitive (DSS) rats at 6 weeks of age were assigned to three groups: low-salt diet (DSS/L; 0.3% NaCl), high-salt diet (DSS/H; 8% NaCl), and high-salt diet treated with ARB, olmesartan at 1 mg/kg. RESULTS DSS/H rats exhibited hypertension, leakage from brain microvessels in the hippocampus, and impaired cognitive functions, which were associated with increased brain AngII levels, as well as decreased mRNA levels of tight junctions (TJs) and collagen-IV in the hippocampus. In DSS/H rats, olmesartan treatment, at a dose that did not alter blood pressure, restored the cognitive decline, and ameliorated leakage from brain microvessels. Olmesartan also decreased brain AngII levels and restored mRNA expression of TJs and collagen-IV in DSS/H rats. CONCLUSIONS These results suggest that during development of salt-dependent hypertension, activation of the brain RAS contributes to BBB disruption and cognitive impairment. Treatment with an ARB could elicit neuroprotective effects in cognitive disorders by preventing BBB permeability, which is independent of blood pressure changes. PMID:21164491

Synthesis of palm-based polyurethane-LiClO{sub 4} via prepolymerization

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

Sien, Jason Wong Chee; School of Biosciences, Taylor’s University, Subang Jaya; Badri, Khairiah Haji

2015-09-25

Palm-based polyurethane (pPU) with varying lithium salt (LiClO{sub 4}) content was synthesized. Higher loading percentage of LiClO{sub 4} in the pPU led to the inhibition of prepolymerization process from taking place. Hydrogen bonded C=O was detected in the FTIR spectrum indicating the hydrogen bonding between the urethane bonds. Ordered complexed C=O was observed in the FTIR spectrum confirming the complex formation between urethane bond and Li{sup +} ion. DSC thermogram showed the increase in the LiClO{sub 4} content could increase the glass transition temperature. SEM micrographs exhibited that more bubbles were formed when the LiClO{sub 4} increased from 10 tomore » 30wt% indicating the reaction between free isocyanate groups with moisture presence in the salt due to the hygroscopic properties of LiClO{sub 4}.« less

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…

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…

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…

Awareness and Cognitive Load Levels of Teacher Candidates towards Student Products Made by Digital Storytelling

ERIC Educational Resources Information Center

Kilic, Figen

2014-01-01

The purpose of this research is to assess the student products created by digital storytelling, and to determine the awareness towards learning the topic and the cognitive loads of students during the process. Research was performed with a total of 52 teacher candidates attending 2nd class at "Classroom Teacher" department of Mersin…

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…

The Effects of Arousal Presented by a Pedagogical Agent on English Language Learners' Situational Interest, Cognitive Load and Reading Comprehension in Online Reading Tasks

ERIC Educational Resources Information Center

Drobisz, Jack

2017-01-01

This research examined how four different animated pedagogical agent implementations, which focus on perceptual and inquiry arousal conditions of attention as defined in Keller's ARCS model of motivational design (Keller, 2009), impact English language learners' situational interest, cognitive load, and reading comprehension in online readings…

Cognitive Load and Attentional Demands during Objects' Position Change in Real and Digital Environments

ERIC Educational Resources Information Center

Zacharis, Georgios K.; Mikropoulos, Tassos Anastasios; Kalyvioti, Katerina

2016-01-01

Studies showed that two-dimensional (2D) and three-dimensional (3D) educational content contributes to learning. Although there were many studies with 3D stereoscopic learning environments, only a few studies reported on the differences between real, 2D, and 3D scenes, as far as cognitive load and attentional demands were concerned. We used…

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…

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…

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…

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…

Cognitive Load Criteria for Critical Evaluation and Selection of Web-Based Resources for Science Teaching.

ERIC Educational Resources Information Center

Klemm, E. Barbara; Iding, Marie K.; Crosby, Martha E.

This study addresses the need to develop research-based criteria for science teacher educators to use in preparing teachers to critically evaluate and select web-based resources for their students' use. The study focuses on the cognitive load imposed on the learner for tasks required in using text, illustrations, and other features of multi-…

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…

The Effects of Task-Induced Involvement Load on Word Learning and Confidence Judgments Mediated by Knowledge and Regulation of Cognition

ERIC Educational Resources Information Center

Teng, Feng

2017-01-01

The relationships between knowledge and regulation of cognition and how they interact to mediate the effects of task-induced involvement load on word learning and confidence judgments were investigated. The participants were 77 undergraduate English majors. They were required to complete a checklist on metacognition. Subsequently, they were…

Determination Instructions Efficiency of Teaching Methods in Teaching Physics in the Case of Teaching Unit "Viscosity. Newtonian and Stokes Law"

ERIC Educational Resources Information Center

Radulovic, Branka; Stojanovic, Maja

2015-01-01

The use of different teaching methods has resulted in different quality and quantity of students' knowledge. For this reason, it is important to constantly review the teaching methods and applied most effectively. One way of determining instruction efficiency is by using cognitive load and student achievement. Cognitive load can be generally…

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…

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…

The Effect of Agent-Based Lectures on Student Learning and Conceptual Change in an Online Inquiry-Based Learning Environment

ERIC Educational Resources Information Center

Chang, Ju-Yu

2013-01-01

Cognitive load theorists claim that problem-centered instruction is not an effective instruction because it is not compatible with human cognitive structure. They argue that the nature of problem-centered instruction tends to over-load learner working memory capacity. That is why many problem-centered practices fail. To better support students and…

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…

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…

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…

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.