Comparing performance in discrete and continuous comparison tasks.

PubMed

Leibovich, Tali; Henik, Avishai

2014-05-01

The approximate number system (ANS) theory suggests that all magnitudes, discrete (i.e., number of items) or continuous (i.e., size, density, etc.), are processed by a shared system and comply with Weber's law. The current study reexamined this notion by comparing performance in discrete (comparing numerosities of dot arrays) and continuous (comparisons of area of squares) tasks. We found that: (a) threshold of discrimination was higher for continuous than for discrete comparisons; (b) while performance in the discrete task complied with Weber's law, performance in the continuous task violated it; and (c) performance in the discrete task was influenced by continuous properties (e.g., dot density, dot cumulative area) of the dot array that were not predictive of numerosities or task relevant. Therefore, we propose that the magnitude processing system (MPS) is actually divided into separate (yet interactive) systems for discrete and continuous magnitude processing. Further subdivisions are discussed. We argue that cooperation between these systems results in a holistic comparison of magnitudes, one that takes into account continuous properties in addition to numerosities. Considering the MPS as two systems opens the door to new and important questions that shed light on both normal and impaired development of the numerical system.

Symbolic Number Comparison Is Not Processed by the Analog Number System: Different Symbolic and Non-symbolic Numerical Distance and Size Effects

PubMed Central

Krajcsi, Attila; Lengyel, Gábor; Kojouharova, Petia

2018-01-01

HIGHLIGHTS We test whether symbolic number comparison is handled by an analog noisy system.Analog system model has systematic biases in describing symbolic number comparison.This suggests that symbolic and non-symbolic numbers are processed by different systems. Dominant numerical cognition models suppose that both symbolic and non-symbolic numbers are processed by the Analog Number System (ANS) working according to Weber's law. It was proposed that in a number comparison task the numerical distance and size effects reflect a ratio-based performance which is the sign of the ANS activation. However, increasing number of findings and alternative models propose that symbolic and non-symbolic numbers might be processed by different representations. Importantly, alternative explanations may offer similar predictions to the ANS prediction, therefore, former evidence usually utilizing only the goodness of fit of the ANS prediction is not sufficient to support the ANS account. To test the ANS model more rigorously, a more extensive test is offered here. Several properties of the ANS predictions for the error rates, reaction times, and diffusion model drift rates were systematically analyzed in both non-symbolic dot comparison and symbolic Indo-Arabic comparison tasks. It was consistently found that while the ANS model's prediction is relatively good for the non-symbolic dot comparison, its prediction is poorer and systematically biased for the symbolic Indo-Arabic comparison. We conclude that only non-symbolic comparison is supported by the ANS, and symbolic number comparisons are processed by other representation. PMID:29491845

Assessing Young Children's Number Magnitude Representation: A Comparison between Novel and Conventional Tasks

ERIC Educational Resources Information Center

Reid, Erin E.; Baroody, Arthur J.; Purpura, David J.

2015-01-01

Previously, researchers have relied on asking young children to plot a given number on a 0-to-10 number line to assess their mental representation of numbers 1 to 9. However, such a ("conventional") number-to-position (N-P) task may underestimate the accuracy of young children's magnitude estimates and misrepresent the nature of their…

Mathematical difficulties in developmental coordination disorder: Symbolic and nonsymbolic number processing.

PubMed

Gomez, Alice; Piazza, Manuela; Jobert, Antoinette; Dehaene-Lambertz, Ghislaine; Dehaene, Stanislas; Huron, Caroline

2015-01-01

At school, children with Developmental Coordination Disorder (DCD) struggle with mathematics. However, little attention has been paid to their numerical cognition abilities. The goal of this study was to better understand the cognitive basis for mathematical difficulties in children with DCD. Twenty 7-to-10 years-old children with DCD were compared to twenty age-matched typically developing children using dot and digit comparison tasks to assess symbolic and nonsymbolic number processing and in a task of single digits additions. Results showed that children with DCD had lower performance in nonsymbolic and symbolic number comparison tasks than typically developing children. They were also slower to solve simple addition problems. Moreover, correlational analyses showed that children with DCD who experienced greater impairments in the nonsymbolic task also performed more poorly in the symbolic tasks. These findings suggest that DCD impairs both nonsymbolic and symbolic number processing. A systematic assessment of numerical cognition in children with DCD could provide a more comprehensive picture of their deficits and help in proposing specific remediation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Parietal dysfunction during number processing in children with fetal alcohol spectrum disorders

PubMed Central

Woods, K.J.; Meintjes, E.M.; Molteno, C.D.; Jacobson, S.W.; Jacobson, J.L.

2015-01-01

Number processing deficits are frequently seen in children prenatally exposed to alcohol. Although the parietal lobe, which is known to mediate several key aspects of number processing, has been shown to be structurally impaired in fetal alcohol spectrum disorders (FASD), effects on functional activity in this region during number processing have not previously been investigated. This fMRI study of 49 children examined differences in activation associated with prenatal alcohol exposure in five key parietal regions involved in number processing, using tasks involving simple addition and magnitude comparison. Despite generally similar behavioral performance, in both tasks greater prenatal alcohol exposure was related to less activation in an anterior section of the right horizontal intraparietal sulcus known to mediate mental representation and manipulation of quantity. Children with fetal alcohol syndrome and partial fetal alcohol syndrome appeared to compensate for this deficit by increased activation of the angular gyrus during the magnitude comparison task. PMID:26199871

Domain-Specific and Domain-General Changes in Children's Development of Number Comparison

ERIC Educational Resources Information Center

Holloway, Ian D.; Ansari, Daniel

2008-01-01

The numerical distance effect (inverse relationship between numerical distance and reaction time in relative number comparison tasks) has frequently been used to characterize the mental representation of number. The size of the distance effect decreases over developmental time. However, it is unclear whether this reduction simply reflects…

Unpacking symbolic number comparison and its relation with arithmetic in adults.

PubMed

Sasanguie, Delphine; Lyons, Ian M; De Smedt, Bert; Reynvoet, Bert

2017-08-01

Symbolic number - or digit - comparison has been a central tool in the domain of numerical cognition for decades. More recently, individual differences in performance on this task have been shown to robustly relate to individual differences in more complex math processing - a result that has been replicated across many different age groups. In this study, we 'unpack' the underlying components of digit comparison (i.e. digit identification, digit to number-word matching, digit ordering and general comparison) in a sample of adults. In a first experiment, we showed that digit comparison performance was most strongly related to digit ordering ability - i.e., the ability to judge whether symbolic numbers are in numerical order. Furthermore, path analyses indicated that the relation between digit comparison and arithmetic was partly mediated by digit ordering and fully mediated when non-numerical (letter) ordering was also entered into the model. In a second experiment, we examined whether a general order working memory component could account for the relation between digit comparison and arithmetic. It could not. Instead, results were more consistent with the notion that fluent access and activation of long-term stored associations between numbers explains the relation between arithmetic and both digit comparison and digit ordering tasks. Copyright © 2017 Elsevier B.V. All rights reserved.

Differences in the acuity of the Approximate Number System in adults: the effect of mathematical ability.

PubMed

Guillaume, Mathieu; Nys, Julie; Mussolin, Christophe; Content, Alain

2013-11-01

It is largely admitted that processing numerosity relies on an innate Approximate Number System (ANS), and recent research consistently observed a relationship between ANS acuity and mathematical ability in childhood. However, studies assessing this relationship in adults led to contradictory results. In this study, adults with different levels of mathematical expertise performed two tasks on the same pairs of dot collections, based either on numerosity comparison or on cumulative area comparison. Number of dots and cumulative area were congruent in half of the stimuli, and incongruent in the other half. The results showed that adults with higher mathematical ability obtained lower Weber fractions in the numerical condition than participants with lower mathematical ability. Further, adults with lower mathematical ability were more affected by the interference of the continuous dimension in the numerical comparison task, whereas conversely higher-expertise adults showed stronger interference of the numerical dimension in the continuous comparison task. Finally, ANS acuity correlated with arithmetic performance. Taken together, the data suggest that individual differences in ANS acuity subsist in adulthood, and that they are related to mathematical ability. © 2013.

Task-Driven Comparison of Topic Models.

PubMed

Alexander, Eric; Gleicher, Michael

2016-01-01

Topic modeling, a method of statistically extracting thematic content from a large collection of texts, is used for a wide variety of tasks within text analysis. Though there are a growing number of tools and techniques for exploring single models, comparisons between models are generally reduced to a small set of numerical metrics. These metrics may or may not reflect a model's performance on the analyst's intended task, and can therefore be insufficient to diagnose what causes differences between models. In this paper, we explore task-centric topic model comparison, considering how we can both provide detail for a more nuanced understanding of differences and address the wealth of tasks for which topic models are used. We derive comparison tasks from single-model uses of topic models, which predominantly fall into the categories of understanding topics, understanding similarity, and understanding change. Finally, we provide several visualization techniques that facilitate these tasks, including buddy plots, which combine color and position encodings to allow analysts to readily view changes in document similarity.

Comparisons and Evaluation of Hall Thruster Models

DTIC Science & Technology

2002-03-20

COVERED (FROM - TO) 20-04-2001 to 20-04-2002 4. TITLE AND SUBTITLE comparisons and Evaluation of Hall Thruster Models Unclassified 5a. CONTRACT NUMBER...TITLE AND SUBTITLE Comparisons and Evaluation of Hall Thruster Models 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5d. TASK NUMBER 6. AUTHOR(S...evaluation of Hall thruster models G. J. M. Hagelaar, J. Bareilles, L. Garrigues, and J.-P. Boeuf CPAT, Bâtiment 3R2, Université Paul Sabatier 118 Route

The link between mental rotation ability and basic numerical representations

PubMed Central

Thompson, Jacqueline M.; Nuerk, Hans-Christoph; Moeller, Korbinian; Cohen Kadosh, Roi

2013-01-01

Mental rotation and number representation have both been studied widely, but although mental rotation has been linked to higher-level mathematical skills, to date it has not been shown whether mental rotation ability is linked to the most basic mental representation and processing of numbers. To investigate the possible connection between mental rotation abilities and numerical representation, 43 participants completed four tasks: 1) a standard pen-and-paper mental rotation task; 2) a multi-digit number magnitude comparison task assessing the compatibility effect, which indicates separate processing of decade and unit digits; 3) a number-line mapping task, which measures precision of number magnitude representation; and 4) a random number generation task, which yields measures both of executive control and of spatial number representations. Results show that mental rotation ability correlated significantly with both size of the compatibility effect and with number mapping accuracy, but not with any measures from the random number generation task. Together, these results suggest that higher mental rotation abilities are linked to more developed number representation, and also provide further evidence for the connection between spatial and numerical abilities. PMID:23933002

Individual Differences in Inhibitory Control, Not Non-Verbal Number Acuity, Correlate with Mathematics Achievement

PubMed Central

Gilmore, Camilla; Attridge, Nina; Clayton, Sarah; Cragg, Lucy; Johnson, Samantha; Marlow, Neil; Simms, Victoria; Inglis, Matthew

2013-01-01

Given the well-documented failings in mathematics education in many Western societies, there has been an increased interest in understanding the cognitive underpinnings of mathematical achievement. Recent research has proposed the existence of an Approximate Number System (ANS) which allows individuals to represent and manipulate non-verbal numerical information. Evidence has shown that performance on a measure of the ANS (a dot comparison task) is related to mathematics achievement, which has led researchers to suggest that the ANS plays a critical role in mathematics learning. Here we show that, rather than being driven by the nature of underlying numerical representations, this relationship may in fact be an artefact of the inhibitory control demands of some trials of the dot comparison task. This suggests that recent work basing mathematics assessments and interventions around dot comparison tasks may be inappropriate. PMID:23785521

Understanding less than nothing: children's neural response to negative numbers shifts across age and accuracy.

PubMed

Gullick, Margaret M; Wolford, George

2013-01-01

We examined the brain activity underlying the development of our understanding of negative numbers, which are amounts lacking direct physical counterparts. Children performed a paired comparison task with positive and negative numbers during an fMRI session. As previously shown in adults, both pre-instruction fifth-graders and post-instruction seventh-graders demonstrated typical behavioral and neural distance effects to negative numbers, where response times and parietal and frontal activity increased as comparison distance decreased. We then determined the factors impacting the distance effect in each age group. Behaviorally, the fifth-grader distance effect for negatives was significantly predicted only by positive comparison accuracy, indicating that children who were generally better at working with numbers were better at comparing negatives. In seventh-graders, negative number comparison accuracy significantly predicted their negative number distance effect, indicating that children who were better at working with negative numbers demonstrated a more typical distance effect. Across children, as age increased, the negative number distance effect increased in the bilateral IPS and decreased frontally, indicating a frontoparietal shift consistent with previous numerical development literature. In contrast, as negative comparison task accuracy increased, the parietal distance effect increased in the left IPS and decreased in the right, possibly indicating a change from an approximate understanding of negatives' values to a more exact, precise representation (particularly supported by the left IPS) with increasing expertise. These shifts separately indicate the effects of increasing maturity generally in numeric processing and specifically in negative number understanding.

Comparison of Bladder Directed and Pelvic Floor Therapy in Women With Interstitial Cystitis/Bladder Pain Syndrome

DTIC Science & Technology

2017-09-01

PROJECT NUMBER Kenneth M. Peters 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT...AWARD NUMBER: W81XWH-16-1-0307 TITLE: Comparison of Bladder-Directed and Pelvic Floor Therapy in Women With Interstitial Cystitis/Bladder Pain...Pelvic Floor Therapy in Women With Interstitial Cystitis/Bladder Pain Syndrome 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d

An open trial assessment of "The Number Race", an adaptive computer game for remediation of dyscalculia

PubMed Central

Wilson, Anna J; Revkin, Susannah K; Cohen, David; Cohen, Laurent; Dehaene, Stanislas

2006-01-01

Background In a companion article [1], we described the development and evaluation of software designed to remediate dyscalculia. This software is based on the hypothesis that dyscalculia is due to a "core deficit" in number sense or in its access via symbolic information. Here we review the evidence for this hypothesis, and present results from an initial open-trial test of the software in a sample of nine 7–9 year old children with mathematical difficulties. Methods Children completed adaptive training on numerical comparison for half an hour a day, four days a week over a period of five-weeks. They were tested before and after intervention on their performance in core numerical tasks: counting, transcoding, base-10 comprehension, enumeration, addition, subtraction, and symbolic and non-symbolic numerical comparison. Results Children showed specific increases in performance on core number sense tasks. Speed of subitizing and numerical comparison increased by several hundred msec. Subtraction accuracy increased by an average of 23%. Performance on addition and base-10 comprehension tasks did not improve over the period of the study. Conclusion Initial open-trial testing showed promising results, and suggested that the software was successful in increasing number sense over the short period of the study. However these results need to be followed up with larger, controlled studies. The issues of transfer to higher-level tasks, and of the best developmental time window for intervention also need to be addressed. PMID:16734906

Task- and age-dependent effects of visual stimulus properties on children's explicit numerosity judgments.

PubMed

Defever, Emmy; Reynvoet, Bert; Gebuis, Titia

2013-10-01

Researchers investigating numerosity processing manipulate the visual stimulus properties (e.g., surface). This is done to control for the confound between numerosity and its visual properties and should allow the examination of pure number processes. Nevertheless, several studies have shown that, despite different visual controls, visual cues remained to exert their influence on numerosity judgments. This study, therefore, investigated whether the impact of the visual stimulus manipulations on numerosity judgments is dependent on the task at hand (comparison task vs. same-different task) and whether this impact changes throughout development. In addition, we examined whether the influence of visual stimulus manipulations on numerosity judgments plays a role in the relation between performance on numerosity tasks and mathematics achievement. Our findings confirmed that the visual stimulus manipulations affect numerosity judgments; more important, we found that these influences changed with increasing age and differed between the comparison and the same-different tasks. Consequently, direct comparisons between numerosity studies using different tasks and age groups are difficult. No meaningful relationship between the performance on the comparison and same-different tasks and mathematics achievement was found in typically developing children, nor did we find consistent differences between children with and without mathematical learning disability (MLD). Copyright © 2013 Elsevier Inc. All rights reserved.

Are Books Like Number Lines? Children Spontaneously Encode Spatial-Numeric Relationships in a Novel Spatial Estimation Task.

PubMed

Thompson, Clarissa A; Morris, Bradley J; Sidney, Pooja G

2017-01-01

Do children spontaneously represent spatial-numeric features of a task, even when it does not include printed numbers (Mix et al., 2016)? Sixty first grade students completed a novel spatial estimation task by seeking and finding pages in a 100-page book without printed page numbers. Children were shown pages 1 through 6 and 100, and then were asked, "Can you find page X?" Children's precision of estimates on the page finder task and a 0-100 number line estimation task was calculated with the Percent Absolute Error (PAE) formula (Siegler and Booth, 2004), in which lower PAE indicated more precise estimates. Children's numerical knowledge was further assessed with: (1) numeral identification (e.g., What number is this: 57?), (2) magnitude comparison (e.g., Which is larger: 54 or 57?), and (3) counting on (e.g., Start counting from 84 and count up 5 more). Children's accuracy on these tasks was correlated with their number line PAE. Children's number line estimation PAE predicted their page finder PAE, even after controlling for age and accuracy on the other numerical tasks. Children's estimates on the page finder and number line tasks appear to tap a general magnitude representation. However, the page finder task did not correlate with numeral identification and counting-on performance, likely because these tasks do not measure children's magnitude knowledge. Our results suggest that the novel page finder task is a useful measure of children's magnitude knowledge, and that books have similar spatial-numeric affordances as number lines and numeric board games.

Comparing a number line and audio prompts in supporting price comparison by students with intellectual disability.

PubMed

Bouck, Emily C; Satsangi, Rajiv; Bartlett, Whitney

2016-01-01

Price comparison is an important and complex skill, but it lacks sufficient research attention in terms of educating secondary students with intellectual disability and/or autism spectrum disorder. This alternating treatment design study compared the use of a paper-based number line and audio prompts delivered via an audio recorder to support three secondary students with intellectual disability to independently and accuracy compare the price of three separate grocery items. The study consisted of 22 sessions, spread across baseline, intervention, best treatment, and two different generalization phases. Data were collected on the percent of task analysis steps completed independently, the type of prompts needed, students' accuracy selecting the lowest priced item, and task completion time. With both intervention conditions, students were able to independently complete the task analysis steps as well as accurately select the lowest priced item and decrease their task completion time. For two of the students, the audio recorder condition resulted in the greatest independence and for one the number line. For only one student was the condition with the greatest independence also the condition for the highest rate of accuracy. The results suggest both tools can support students with price comparison. Yet, audio recorders offer students and teachers an age-appropriate and setting-appropriate option. Copyright © 2016 Elsevier Ltd. All rights reserved.

Singing numbers…in cognitive space--a dual-task study of the link between pitch, space, and numbers.

PubMed

Fischer, Martin H; Riello, Marianna; Giordano, Bruno L; Rusconi, Elena

2013-04-01

We assessed the automaticity of spatial-numerical and spatial-musical associations by testing their intentionality and load sensitivity in a dual-task paradigm. In separate sessions, 16 healthy adults performed magnitude and pitch comparisons on sung numbers with variable pitch. Stimuli and response alternatives were identical, but the relevant stimulus attribute (pitch or number) differed between tasks. Concomitant tasks required retention of either color or location information. Results show that spatial associations of both magnitude and pitch are load sensitive and that the spatial association for pitch is more powerful than that for magnitude. These findings argue against the automaticity of spatial mappings in either stimulus dimension. Copyright © 2013 Cognitive Science Society, Inc.

Approximate number sense, symbolic number processing, or number-space mappings: what underlies mathematics achievement?

PubMed

Sasanguie, Delphine; Göbel, Silke M; Moll, Kristina; Smets, Karolien; Reynvoet, Bert

2013-03-01

In this study, the performance of typically developing 6- to 8-year-old children on an approximate number discrimination task, a symbolic comparison task, and a symbolic and nonsymbolic number line estimation task was examined. For the first time, children's performances on these basic cognitive number processing tasks were explicitly contrasted to investigate which of them is the best predictor of their future mathematical abilities. Math achievement was measured with a timed arithmetic test and with a general curriculum-based math test to address the additional question of whether the predictive association between the basic numerical abilities and mathematics achievement is dependent on which math test is used. Results revealed that performance on both mathematics achievement tests was best predicted by how well childrencompared digits. In addition, an association between performance on the symbolic number line estimation task and math achievement scores for the general curriculum-based math test measuring a broader spectrum of skills was found. Together, these results emphasize the importance of learning experiences with symbols for later math abilities. Copyright © 2012 Elsevier Inc. All rights reserved.

Rational-number comparison across notation: Fractions, decimals, and whole numbers.

PubMed

Hurst, Michelle; Cordes, Sara

2016-02-01

Although fractions, decimals, and whole numbers can be used to represent the same rational-number values, it is unclear whether adults conceive of these rational-number magnitudes as lying along the same ordered mental continuum. In the current study, we investigated whether adults' processing of rational-number magnitudes in fraction, decimal, and whole-number notation show systematic ratio-dependent responding characteristic of an integrated mental continuum. Both reaction time (RT) and eye-tracking data from a number-magnitude comparison task revealed ratio-dependent performance when adults compared the relative magnitudes of rational numbers, both within the same notation (e.g., fractions vs. fractions) and across different notations (e.g., fractions vs. decimals), pointing to an integrated mental continuum for rational numbers across notation types. In addition, eye-tracking analyses provided evidence of an implicit whole-number bias when we compared values in fraction notation, and individual differences in this whole-number bias were related to the individual's performance on a fraction arithmetic task. Implications of our results for both cognitive development research and math education are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Optical data transmission technology for fixed and drag-on STS payloads umbilicals. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

St.denis, R. W.

1981-01-01

The feasibility of using optical data handling methods to transmit payload checkout and telemetry is discussed. Optical communications are superior to conventional communication systems for the following reasons: high data capacity optical channels; small and light weight optical cables; and optical signal immunity to electromagnetic interference. Task number one analyzed the ground checkout data requirements that may be expected from the payload community. Task number two selected the optical approach based on the interface requirements, the location of the interface, the amount of time required to reconfigure hardware, and the method of transporting the optical signal. Task number three surveyed and selected optical components for the two payload data link. Task number four makes a qualitative comparison of the conventional electrical communication system and the proposed optical communication system.

Numbers Are Associated with Different Types of Spatial Information Depending on the Task

ERIC Educational Resources Information Center

van Dijck, Jean-Philippe; Gevers, Wim; Fias, Wim

2009-01-01

In this study, we examined the nature of the spatial-numerical associations underlying the SNARC-effect by imposing a verbal or spatial working memory load during a parity judgment and a magnitude comparison task. The results showed a double dissociation between the type of working memory load and type of task. The SNARC-effect disappeared under…

Are Books Like Number Lines? Children Spontaneously Encode Spatial-Numeric Relationships in a Novel Spatial Estimation Task

PubMed Central

Thompson, Clarissa A.; Morris, Bradley J.; Sidney, Pooja G.

2017-01-01

Do children spontaneously represent spatial-numeric features of a task, even when it does not include printed numbers (Mix et al., 2016)? Sixty first grade students completed a novel spatial estimation task by seeking and finding pages in a 100-page book without printed page numbers. Children were shown pages 1 through 6 and 100, and then were asked, “Can you find page X?” Children’s precision of estimates on the page finder task and a 0-100 number line estimation task was calculated with the Percent Absolute Error (PAE) formula (Siegler and Booth, 2004), in which lower PAE indicated more precise estimates. Children’s numerical knowledge was further assessed with: (1) numeral identification (e.g., What number is this: 57?), (2) magnitude comparison (e.g., Which is larger: 54 or 57?), and (3) counting on (e.g., Start counting from 84 and count up 5 more). Children’s accuracy on these tasks was correlated with their number line PAE. Children’s number line estimation PAE predicted their page finder PAE, even after controlling for age and accuracy on the other numerical tasks. Children’s estimates on the page finder and number line tasks appear to tap a general magnitude representation. However, the page finder task did not correlate with numeral identification and counting-on performance, likely because these tasks do not measure children’s magnitude knowledge. Our results suggest that the novel page finder task is a useful measure of children’s magnitude knowledge, and that books have similar spatial-numeric affordances as number lines and numeric board games. PMID:29312084

Can Dyscalculics Estimate the Results of Arithmetic Problems?

ERIC Educational Resources Information Center

Ganor-Stern, Dana

2017-01-01

The present study is the first to examine the computation estimation skills of dyscalculics versus controls using the estimation comparison task. In this task, participants judged whether an estimated answer to a multidigit multiplication problem was larger or smaller than a given reference number. While dyscalculics were less accurate than…

Are Secondary School Students Still Hampered by the Natural Number Bias? A Reaction Time Study on Fraction Comparison Tasks

ERIC Educational Resources Information Center

Van Hoof, Jo; Lijnen, Tristan; Verschaffel, Lieven; Van Dooren, Wim

2013-01-01

Rational numbers and particularly fractions are difficult for students. It is often claimed that the "natural number bias" underlies erroneous reasoning about rational numbers. This cross-sectional study investigated the natural number bias in first and fifth year secondary school students. Relying on dual process theory assumptions that…

Common magnitude representation of fractions and decimals is task dependent.

PubMed

Zhang, Li; Fang, Qiaochu; Gabriel, Florence C; Szűcs, Denes

2016-01-01

Although several studies have compared the representation of fractions and decimals, no study has investigated whether fractions and decimals, as two types of rational numbers, share a common representation of magnitude. The current study aimed to answer the question of whether fractions and decimals share a common representation of magnitude and whether the answer is influenced by task paradigms. We included two different number pairs, which were presented sequentially: fraction-decimal mixed pairs and decimal-fraction mixed pairs in all four experiments. Results showed that when the mixed pairs were very close numerically with the distance 0.1 or 0.3, there was a significant distance effect in the comparison task but not in the matching task. However, when the mixed pairs were further apart numerically with the distance 0.3 or 1.3, the distance effect appeared in the matching task regardless of the specific stimuli. We conclude that magnitudes of fractions and decimals can be represented in a common manner, but how they are represented is dependent on the given task. Fractions and decimals could be translated into a common representation of magnitude in the numerical comparison task. In the numerical matching task, fractions and decimals also shared a common representation. However, both of them were represented coarsely, leading to a weak distance effect. Specifically, fractions and decimals produced a significant distance effect only when the numerical distance was larger.

Number sense in the transition from natural to rational numbers.

PubMed

Van Hoof, Jo; Verschaffel, Lieven; Van Dooren, Wim

2017-03-01

Rational numbers are of critical importance both in mathematics and in other fields of science. However, they form a stumbling block for learners. One widely known source of the difficulty learners have with rational numbers is the natural number bias, that is the tendency to (inappropriately) apply natural number properties in rational number tasks. Still, it has been shown that a good understanding of natural numbers is highly predictive for mathematics achievement in general, and for performance on rational number tasks in particular. In this study, we further investigated the relation between learners' natural and rational number knowledge, specifically in cases where a natural number bias may lead to errors. Participants were 140 sixth graders from six different primary schools. Participants completed a symbolic and a non-symbolic natural number comparison task, a number line estimation task, and a rational number sense test. Learners' natural number knowledge was found to be a good predictor of their rational number knowledge. However, after first controlling for learners' general mathematics achievement, their natural number knowledge only predicted the subaspect of operations with rational numbers. The results of this study suggest that the relation between learners' natural and rational number knowledge can largely be explained by their relation with learners' general mathematics achievement. © 2016 The British Psychological Society.

Eye movements during the handwriting of words: Individually and within sentences.

PubMed

Sita, Jodi C; Taylor, Katelyn A

2015-10-01

Handwriting, a complex motor process involves the coordination of both the upper limb and visual system. The gaze behavior that occurs during the handwriting process is an area that has been little studied. This study investigated the eye-movements of adults during writing and reading tasks. Eye and handwriting movements were recorded for six different words over three different tasks. The results compared reading and handwriting the same words, a between condition comparison and a comparison between the two handwriting tasks. Compared to reading, participants produced more fixations during handwriting tasks and the average fixation durations were longer. When reading fixations were found to be mostly around the center of word, whereas fixations when writing appear to be made for each letter in a written word and were located around the base of letters and flowed in a left to right direction. Between the two writing tasks more fixations were made when words were written individually compared to within sentences, yet fixation durations were no different. Correlation of the number of fixations made to kinematic variables revealed that horizontal size and road length held a strong correlation with the number of fixations made by participants. Copyright © 2015 Elsevier B.V. All rights reserved.

Rational numbers: componential versus holistic representation of fractions in a magnitude comparison task.

PubMed

Meert, Gaëlle; Grégoire, Jacques; Noël, Marie-Pascale

2009-08-01

This study investigated whether the mental representation of the fraction magnitude was componential and/or holistic in a numerical comparison task performed by adults. In Experiment 1, the comparison of fractions with common numerators (x/a_x/b) and of fractions with common denominators (a/x_b/x) primed the comparison of natural numbers. In Experiment 2, fillers (i.e., fractions without common components) were added to reduce the regularity of the stimuli. In both experiments, distance effects indicated that participants compared the numerators for a/x_b/x fractions, but that the magnitudes of the whole fractions were accessed and compared for x/a_x/b fractions. The priming effect of x/a_x/b fractions on natural numbers suggested that the interference of the denominator magnitude was controlled during the comparison of these fractions. These results suggested a hybrid representation of their magnitude (i.e., componential and holistic). In conclusion, the magnitude of the whole fraction can be accessed, probably by estimating the ratio between the magnitude of the denominator and the magnitude of the numerator. However, adults might prefer to rely on the magnitudes of the components and compare the magnitudes of the whole fractions only when the use of a componential strategy is made difficult.

Separate mechanisms for magnitude and order processing in the spatial-numerical association of response codes (SNARC) effect: The strange case of musical note values.

PubMed

Prpic, Valter; Fumarola, Antonia; De Tommaso, Matteo; Luccio, Riccardo; Murgia, Mauro; Agostini, Tiziano

2016-08-01

The spatial-numerical association of response codes (SNARC) effect is considered an evidence of the association between numbers and space, with faster left key-press responses to small numbers and faster right key-press responses to large numbers. We examined whether visually presented note values produce a SNARC-like effect. Differently from numbers, note values are represented as a decreasing left-to-right progression, allowing us to disambiguate the contribution of order and magnitude in determining the direction of the effect. Musicians with formal education performed a note value comparison in Experiment 1 (direct task), a line orientation judgment in Experiment 2 (indirect task), and a detection task in Experiment 3 (indirect task). When note values were task relevant (direct task), participants responded faster to large note values with the left key-press, and vice versa. Conversely, when note values were task irrelevant (indirect tasks), the direction of this association was reversed. This evidence suggests the existence of separate mechanisms underlying the SNARC effect. Namely, an Order-Related Mechanism (ORM) and a Magnitude-Related Mechanism (MRM) that are revealed by different task demands. Indeed, according to a new model we proposed, ordinal and magnitude related information appears to be preferentially involved in direct and indirect tasks, respectively. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Comparison between a Terramechanics Model and a Continuum Soil Model Implemented within the Absolute Nodal Coordinate Formulation

DTIC Science & Technology

2012-08-01

Chicago, IL 60607, USA Email: fosterc@uic.edu Paramsothy Jayakumar U.S. Army RDECOM-TARDEC Warren, MI 48397-5000, USA...Mike Letherwood; Paramsothy Jayakumar ; Guangbu Li; Ulysses Contreras; Craig Foster 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7

Reliability and Validity of Nonsymbolic and Symbolic Comparison Tasks in School-Aged Children.

PubMed

Castro, Danilka; Estévez, Nancy; Gómez, David; Dartnell, Pablo Ricardo

2017-12-04

Basic numerical processing has been regularly assessed using numerical nonsymbolic and symbolic comparison tasks. It has been assumed that these tasks index similar underlying processes. However, the evidence concerning the reliability and convergent validity across different versions of these tasks is inconclusive. We explored the reliability and convergent validity between two numerical comparison tasks (nonsymbolic vs. symbolic) in school-aged children. The relations between performance in both tasks and mental arithmetic were described and a developmental trajectories' analysis was also conducted. The influence of verbal and visuospatial working memory processes and age was controlled for in the analyses. Results show significant reliability (p < .001) between Block 1 and 2 for nonsymbolic task (global adjusted RT (adjRT): r = .78, global efficiency measures (EMs): r = .74) and, for symbolic task (adjRT: r = .86, EMs: r = .86). Also, significant convergent validity between tasks (p < .001) for both adjRT (r = .71) and EMs (r = .70) were found after controlling for working memory and age. Finally, it was found the relationship between nonsymbolic and symbolic efficiencies varies across the sample's age range. Overall, these findings suggest both tasks index the same underlying cognitive architecture and are appropriate to explore the Approximate Number System (ANS) characteristics. The evidence supports the central role of ANS in arithmetic efficiency and suggests there are differences across the age range assessed, concerning the extent to which efficiency in nonsymbolic and symbolic tasks reflects ANS acuity.

Processing of Intentional and Automatic Number Magnitudes in Children Born Prematurely: Evidence From fMRI

PubMed Central

Klein, Elise; Moeller, Korbinian; Kiechl-Kohlendorfer, Ursula; Kremser, Christian; Starke, Marc; Cohen Kadosh, Roi; Pupp-Peglow, Ulrike; Schocke, Michael; Kaufmann, Liane

2014-01-01

This study examined the neural correlates of intentional and automatic number processing (indexed by number comparison and physical Stroop task, respectively) in 6- and 7-year-old children born prematurely. Behavioral results revealed significant numerical distance and size congruity effects. Imaging results disclosed (1) largely overlapping fronto-parietal activation for intentional and automatic number processing, (2) a frontal to parietal shift of activation upon considering the risk factors gestational age and birth weight, and (3) a task-specific link between math proficiency and functional magnetic resonance imaging (fMRI) signal within distinct regions of the parietal lobes—indicating commonalities but also specificities of intentional and automatic number processing. PMID:25090014

Spatial and numerical processing in children with high and low visuospatial abilities.

PubMed

Crollen, Virginie; Noël, Marie-Pascale

2015-04-01

In the literature on numerical cognition, a strong association between numbers and space has been repeatedly demonstrated. However, only a few recent studies have been devoted to examine the consequences of low visuospatial abilities on calculation processing. In this study, we wanted to investigate whether visuospatial weakness may affect pure spatial processing as well as basic numerical reasoning. To do so, the performances of children with high and low visuospatial abilities were directly compared on different spatial tasks (the line bisection and Simon tasks) and numerical tasks (the number bisection, number-to-position, and numerical comparison tasks). Children from the low visuospatial group presented the classic Simon and SNARC (spatial numerical association of response codes) effects but showed larger deviation errors as compared with the high visuospatial group. Our results, therefore, demonstrated that low visuospatial abilities did not change the nature of the mental number line but rather led to a decrease in its accuracy. Copyright © 2014 Elsevier Inc. All rights reserved.

The Influence of Learner Strategies on Oral Presentations: A Comparison between Group and Individual Performance

ERIC Educational Resources Information Center

Chou, Mu-hsuan

2011-01-01

Cooperative learning has frequently been used in language classrooms, from in-class task-based group work to group presentations. Research suggests that cooperative learning provides mutual support, as well as successful and effective learning outcomes of tasks. The present research addressed a number of problems discovered in group oral…

Meanings for Fraction as Number-Measure by Exploring the Number Line

ERIC Educational Resources Information Center

Psycharis, Giorgos; Latsi, Maria; Kynigos, Chronis

2009-01-01

This paper reports on a case-study design experiment in the domain of fraction as number-measure. We designed and implemented a set of exploratory tasks concerning comparison and ordering of fractions as well as operations with fractions. Two groups of 12-year-old students worked collaboratively using paper and pencil as well as a specially…

A Comparison of Prostate Cancer Incidence Between U.S. Air Force Enlisted Aircrew

DTIC Science & Technology

2011-06-30

COL DAVID B. RHODES, RAM Prog Dir COL ROBERT E. CARROLL , Chair FE...PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) Joseph A. Lopez 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING...ORGANIZATION NAME( S ) AND ADDRESS(ES) USAF School of Aerospace Medicine Aerospace Medicine Education/FEEG 2510 Fifth St. Wright-Patterson AFB, OH 45433-7913

The counting abilities of children with specific language impairment: a comparison of oral and gestural tasks.

PubMed

Fazio, B B

1994-04-01

This study examined the counting abilities of preschool children with specific language impairment compared to language-matched and mental-age-matched peers. In order to determine the nature of the difficulties SLI children exhibited in counting, the subjects participated in a series of oral counting tasks and a series of gestural tasks that used an invented counting system based on pointing to body parts. Despite demonstrating knowledge of many of the rules associated with counting, SLI preschool children displayed marked difficulty in counting objects. On oral counting tasks, they showed difficulty with rote counting, displayed a limited repertoire of number terms, and miscounted sets of objects. However, on gestural counting tasks, SLI children's performance was significantly better. These findings suggest that SLI children have a specific difficulty with the rote sequential aspect of learning number words.

A comparison of usability factors of four mobile devices for accessing healthcare information by adolescents.

PubMed

Sheehan, B; Lee, Y; Rodriguez, M; Tiase, V; Schnall, R

2012-01-01

Mobile health (mHealth) is a growing field aimed at developing mobile information and communication technologies for healthcare. Adolescents are known for their ubiquitous use of mobile technologies in everyday life. However, the use of mHealth tools among adolescents is not well described. We examined the usability of four commonly used mobile devices (an iPhone, an Android with touchscreen keyboard, an Android with built-in keyboard, and an iPad) for accessing healthcare information among a group of urban-dwelling adolescents. Guided by the FITT (Fit between Individuals, Task, and Technology) framework, a thinkaloud protocol was combined with a questionnaire to describe usability on three dimensions: 1) task-technology fit; 2) individual-technology fit; and 3) individual-task fit. For task-technology fit, we compared the efficiency, and effectiveness of each of the devices tested and found that the iPhone was the most usable had the fewest errors and prompts and had the lowest mean overall task time For individual-task fit, we compared efficiency and learnability measures by website tasks and found no statistically significant effect on tasks steps, task time and number of errors. Following our comparison of success rates by website tasks, we compared the difference between two mobile applications which were used for diet tracking and found statistically significant effect on tasks steps, task time and number of errors. For individual-technology fit, interface quality was significantly different across devices indicating that this is an important factor to be considered in developing future mobile devices. All of our users were able to complete all of the tasks, however the time needed to complete the tasks was significantly different by mobile device and mHealth application. Future design of mobile technology and mHealth applications should place particular importance on interface quality.

Variation in Strategy Use Across Measures of Verbal Working Memory

PubMed Central

Morrison, Alexandra B; Rosenbaum, Gail M.; Fair, Damien; Chein, Jason M.

2016-01-01

The working memory (WM) literature contains a number of tasks that vary on dimensions such as when or how memory items are reported. In addition to the ways in which WM tasks are designed to differ, tasks may also diverge according to the strategies participants use during task performance. The present study included seven tasks from the WM literature, each requiring short-term retention of verbal items. Following completion of a small number of trials from each task, individuals completed a self-report questionnaire to identify their primary strategy. Results indicated substantial variation across individuals for a given task, and within the same individual across tasks. Moreover, while direct comparisons between tasks showed that some tasks evinced similar patterns of strategy use despite differing task demands, others showed markedly different patterns of self-reported strategy use. A community detection algorithm aimed at identifying groups of individuals based on their profile of strategic choices revealed unique communities of individuals who are dependent on specific strategies under varying demands. Together, the findings suggest that researchers using common working memory paradigms should very carefully consider the implications of variation in strategy use when interpreting their findings. PMID:27038310

Developmental specialization in the right intraparietal sulcus for the abstract representation of numerical magnitude.

PubMed

Holloway, Ian D; Ansari, Daniel

2010-11-01

Because number is an abstract quality of a set, the way in which a number is externally represented does not change its quantitative meaning. In this study, we examined the development of the brain regions that support format-independent representation of numerical magnitude. We asked children and adults to perform both symbolic (Hindu-Arabic numerals) and nonsymbolic (arrays of squares) numerical comparison tasks as well as two control tasks while their brains were scanned using fMRI. In a preliminary analysis, we calculated the conjunction between symbolic and nonsymbolic numerical comparison. We then examined in which brain regions this conjunction differed between children and adults. This analysis revealed a large network of visual and parietal regions that showed greater activation in adults relative to children. In our primary analysis, we examined age-related differences in the conjunction of symbolic and nonsymbolic comparison after subtracting the control tasks. This analysis revealed a much more limited set of regions including the right inferior parietal lobe near the intraparietal sulcus. In addition to showing increased activation to both symbolic and nonsymbolic magnitudes over and above activation related to response selection, this region showed age-related differences in the distance effect. Our findings demonstrate that the format-independent representation of numerical magnitude in the right inferior parietal lobe is the product of developmental processes of cortical specialization and highlight the importance of using appropriate control tasks when conducting developmental neuroimaging studies.

Costs and benefits of integrating information between the cerebral hemispheres: a computational perspective.

PubMed

Belger, A; Banich, M T

1998-07-01

Because interaction of the cerebral hemispheres has been found to aid task performance under demanding conditions, the present study examined how this effect is moderated by computational complexity, the degree of lateralization for a task, and individual differences in asymmetric hemispheric activation (AHA). Computational complexity was manipulated across tasks either by increasing the number of inputs to be processed or by increasing the number of steps to a decision. Comparison of within- and across-hemisphere trials indicated that the size of the between-hemisphere advantage increased as a function of task complexity, except for a highly lateralized rhyme decision task that can only be performed by the left hemisphere. Measures of individual differences in AHA revealed that when task demands and an individual's AHA both load on the same hemisphere, the ability to divide the processing between the hemispheres is limited. Thus, interhemispheric division of processing improves performance at higher levels of computational complexity only when the required operations can be divided between the hemispheres.

Examining pitch and numerical magnitude processing in congenital amusia: A quasi-experimental pilot study.

PubMed

Nunes-Silva, Marilia; Moura, Ricardo; Lopes-Silva, Júlia Beatriz; Haase, Vitor Geraldi

2016-08-01

Congenital amusia is a developmental disorder associated with deficits in pitch height discrimination or in integrating pitch sequences into melodies. This quasi-experimental pilot study investigated whether there is an association between pitch and numerical processing deficits in congenital amusia. Since pitch height discrimination is considered a form of magnitude processing, we investigated whether individuals with amusia present an impairment in numerical magnitude processing, which would reflect damage to a generalized magnitude system. Alternatively, we investigated whether the numerical processing deficit would reflect a disconnection between nonsymbolic and symbolic number representations. This study was conducted with 11 adult individuals with congenital amusia and a control comparison group of 6 typically developing individuals. Participants performed nonsymbolic and symbolic magnitude comparisons and number line tasks. Results were available from previous testing using the Montreal Battery of Evaluation of Amusia (MBEA) and a pitch change detection task (PCD). Compared to the controls, individuals with amusia exhibited no significant differences in their performance on both the number line and the nonsymbolic magnitude tasks. Nevertheless, they showed significantly worse performance on the symbolic magnitude task. Moreover, individuals with congenital amusia, who presented worse performance in the Meter subtest, also presented less precise nonsymbolic numerical representation. The relationship between meter and nonsymbolic numerical discrimination could indicate a general ratio processing deficit. The finding of preserved nonsymbolic numerical magnitude discrimination and mental number line representations, with impaired symbolic number processing, in individuals with congenital amusia indicates that (a) pitch height and numerical magnitude processing may not share common neural representations, and (b) in addition to pitch processing, individuals with amusia may present a deficit in accessing nonsymbolic numerical representations from symbolic representations. The symbolic access deficit could reflect a widespread impairment in the establishment of cortico-cortical connections between association areas.

On the functional role of human parietal cortex in number processing: How gender mediates the impact of a 'virtual lesion' induced by rTMS.

PubMed

Knops, Andre; Nuerk, Hans-Christoph; Sparing, Roland; Foltys, Henrik; Willmes, Klaus

2006-01-01

Areas around the horizontal part of the intraparietal sulcus (hIPS) have repeatedly been reported to participate in processing numerical magnitude. Using transcranial magnetic stimulation (TMS), we investigated the functional role of the hIPS by examining two effects from the domain of numerical cognition: in magnitude comparison tasks response latencies are inversely related to the numerical distance between two numbers. This distance effect indexes access to the mental number representation. In magnitude comparison tasks responses are faster when decade and unit comparison would lead to the same decision (e.g. 42_57, 4 < 5 and 2 < 7) than when they would not (e.g. 47_62, 4 < 6 but 7 > 2). This compatibility effect reflects unit-decade integration processes. Differential susceptibility of (fe)male participants to TMS was examined. We applied repetitive TMS (rTMS; 1Hz for 10 min) over the left hIPS in 12 participants (6 female). No stimulation and vertex stimulation served as control conditions. The effect of rTMS was mediated by gender: in male participants, the distance effect decreased after TMS over hIPS. For female participants distance and compatibility effect both increased. This modulation of the compatibility effect was limited in duration to no more than 4 min. The hIPS seems to be functionally involved both in number magnitude processing and in integrating unit-decade magnitude information of two-digit numbers. Relative hemispheric specialization of the hIPS with respect to two-digit magnitude comparison is discussed.

Measuring effects of voluntary attention: a comparison among predictive arrow, colour, and number cues.

PubMed

Olk, Bettina; Tsankova, Elena; Petca, A Raisa; Wilhelm, Adalbert F X

2014-10-01

The Posner cueing paradigm is one of the most widely used paradigms in attention research. Importantly, when employing it, it is critical to understand which type of orienting a cue triggers. It has been suggested that large effects elicited by predictive arrow cues reflect an interaction of involuntary and voluntary orienting. This conclusion is based on comparisons of cueing effects of predictive arrows, nonpredictive arrows (involuntary orienting), and predictive numbers (voluntary orienting). Experiment 1 investigated whether this conclusion is restricted to comparisons with number cues and showed similar results to those of previous studies, but now for comparisons to predictive colour cues, indicating that the earlier conclusion can be generalized. Experiment 2 assessed whether the size of a cueing effect is related to the ease of deriving direction information from a cue, based on the rationale that effects for arrows may be larger, because it may be easier to process direction information given by symbols such as arrows than that given by other cues. Indeed, direction information is derived faster and more accurately from arrows than from colour and number cues in a direction judgement task, and cueing effects are larger for arrows than for the other cues. Importantly though, performance in the two tasks is not correlated. Hence, the large cueing effects of arrows are not a result of the ease of information processing, but of the types of orienting that the arrows elicit.

Risk approximation in decision making: approximative numeric abilities predict advantageous decisions under objective risk.

PubMed

Mueller, Silke M; Schiebener, Johannes; Delazer, Margarete; Brand, Matthias

2018-01-22

Many decision situations in everyday life involve mathematical considerations. In decisions under objective risk, i.e., when explicit numeric information is available, executive functions and abilities to handle exact numbers and ratios are predictors of objectively advantageous choices. Although still debated, exact numeric abilities, e.g., normative calculation skills, are assumed to be related to approximate number processing skills. The current study investigates the effects of approximative numeric abilities on decision making under objective risk. Participants (N = 153) performed a paradigm measuring number-comparison, quantity-estimation, risk-estimation, and decision-making skills on the basis of rapid dot comparisons. Additionally, a risky decision-making task with exact numeric information was administered, as well as tasks measuring executive functions and exact numeric abilities, e.g., mental calculation and ratio processing skills, were conducted. Approximative numeric abilities significantly predicted advantageous decision making, even beyond the effects of executive functions and exact numeric skills. Especially being able to make accurate risk estimations seemed to contribute to superior choices. We recommend approximation skills and approximate number processing to be subject of future investigations on decision making under risk.

Mathematics anxiety reduces default mode network deactivation in response to numerical tasks.

PubMed

Pletzer, Belinda; Kronbichler, Martin; Nuerk, Hans-Christoph; Kerschbaum, Hubert H

2015-01-01

Mathematics anxiety is negatively related to mathematics performance, thereby threatening the professional success. Preoccupation with the emotional content of the stimuli may consume working memory resources, which may be reflected in decreased deactivation of areas associated with the default mode network (DMN) activated during self-referential and emotional processing. The common problem is that math anxiety is usually associated with poor math performance, so that any group differences are difficult to interpret. Here we compared the BOLD-response of 18 participants with high (HMAs) and 18 participants with low mathematics anxiety (LMAs) matched for their mathematical performance to two numerical tasks (number comparison, number bisection). During both tasks, we found stronger deactivation within the DMN in LMAs compared to HMAs, while BOLD-response in task-related activation areas did not differ between HMAs and LMAs. The difference in DMN deactivation between the HMA and LMA group was more pronounced in stimuli with additional requirement on inhibitory functions, but did not differ between number magnitude processing and arithmetic fact retrieval.

Mathematics anxiety reduces default mode network deactivation in response to numerical tasks

PubMed Central

Pletzer, Belinda; Kronbichler, Martin; Nuerk, Hans-Christoph; Kerschbaum, Hubert H.

2015-01-01

Mathematics anxiety is negatively related to mathematics performance, thereby threatening the professional success. Preoccupation with the emotional content of the stimuli may consume working memory resources, which may be reflected in decreased deactivation of areas associated with the default mode network (DMN) activated during self-referential and emotional processing. The common problem is that math anxiety is usually associated with poor math performance, so that any group differences are difficult to interpret. Here we compared the BOLD-response of 18 participants with high (HMAs) and 18 participants with low mathematics anxiety (LMAs) matched for their mathematical performance to two numerical tasks (number comparison, number bisection). During both tasks, we found stronger deactivation within the DMN in LMAs compared to HMAs, while BOLD-response in task-related activation areas did not differ between HMAs and LMAs. The difference in DMN deactivation between the HMA and LMA group was more pronounced in stimuli with additional requirement on inhibitory functions, but did not differ between number magnitude processing and arithmetic fact retrieval. PMID:25954179

Distinct representations of subtraction and multiplication in the neural systems for numerosity and language

PubMed Central

Prado, Jérôme; Mutreja, Rachna; Zhang, Hongchuan; Mehta, Rucha; Desroches, Amy S.; Minas, Jennifer E.; Booth, James R.

2010-01-01

It has been proposed that recent cultural inventions such as symbolic arithmetic recycle evolutionary older neural mechanisms. A central assumption of this hypothesis is that the degree to which a pre-existing mechanism is recycled depends upon the degree of similarity between its initial function and the novel task. To test this assumption, we investigated whether the brain region involved in magnitude comparison in the intraparietal sulcus (IPS), localized by a numerosity comparison task, is recruited to a greater degree by arithmetic problems that involve number comparison (single-digit subtractions) than by problems that involve retrieving facts from memory (single-digit multiplications). Our results confirmed that subtractions are associated with greater activity in the IPS than multiplications, whereas multiplications elicit greater activity than subtractions in regions involved in verbal processing including the middle temporal gyrus and inferior frontal gyrus that were localized by a phonological processing task. Pattern analyses further indicated that the neural mechanisms more active for subtraction than multiplication in the IPS overlap with those involved in numerosity comparison, and that the strength of this overlap predicts inter-individual performance in the subtraction task. These findings provide novel evidence that elementary arithmetic relies on the co-option of evolutionary older neural circuits. PMID:21246667

Two-digit number comparison: Decade-unit and unit-decade produce the same compatibility effect with number words.

PubMed

Macizo, Pedro; Herrera, Amparo

2010-03-01

This study explored the processing of 2-digit number words by examining the unit-decade compatibility effect in Spanish. Participants were required to choose the larger of 2-digit number words presented in verbal notation. In compatible trials the decade and unit comparisons led to the same response (e.g., 53-68) while in incompatible trials the decade and unit comparisons led to different responses (e.g., 59-74). Participants were slower on compatible trials as compared to incompatible trials. In Experiments 2 and 3, we evaluated whether the reverse compatibility effect in Spanish was only due to a pure left-to-right encoding which favours the decade processing in this language (decade-unit order). When participants processed 2-digit number words presented in reverse form (in the unit-decade order), the same reverse compatibility effect was found. This pattern of results suggests that participants have learnt a language-dependent process for analysing written numbers which is used irrespective of the specific arrangement of units and decades in the comparison task. 2010 APA, all rights reserved.

Intranasal Rapamycin Rescues Mice from Staphylococcal Enterotoxin B-Induced Shock

DTIC Science & Technology

2012-09-18

PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Medical Research Institute of...Infectious Diseases,Fort Detrick,MD,21702 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR...Student’s t-test. Statistical comparisons of survival data were performed by Fisher’s exact test with Stata software (Stata Corp., College Station, TX

Analogical reasoning in amazons.

PubMed

Obozova, Tanya; Smirnova, Anna; Zorina, Zoya; Wasserman, Edward

2015-11-01

Two juvenile orange-winged amazons (Amazona amazonica) were initially trained to match visual stimuli by color, shape, and number of items, but not by size. After learning these three identity matching-to-sample tasks, the parrots transferred discriminative responding to new stimuli from the same categories that had been used in training (other colors, shapes, and numbers of items) as well as to stimuli from a different category (stimuli varying in size). In the critical testing phase, both parrots exhibited reliable relational matching-to-sample (RMTS) behavior, suggesting that they perceived and compared the relationship between objects in the sample stimulus pair to the relationship between objects in the comparison stimulus pairs, even though no physical matches were possible between items in the sample and comparison pairs. The parrots spontaneously exhibited this higher-order relational responding without having ever before been trained on RMTS tasks, therefore joining apes and crows in displaying this abstract cognitive behavior.

Development of fraction comparison strategies: A latent transition analysis.

PubMed

Rinne, Luke F; Ye, Ai; Jordan, Nancy C

2017-04-01

The present study investigated the development of fraction comparison strategies through a longitudinal analysis of children's responses to a fraction comparison task in 4th through 6th grades (N = 394). Participants were asked to choose the larger value for 24 fraction pairs blocked by fraction type. Latent class analysis of performance over item blocks showed that most children initially exhibited a "whole number bias," indicating that larger numbers in numerators and denominators produce larger fraction values. However, some children instead chose fractions with smaller numerators and denominators, demonstrating a partial understanding that smaller numbers can yield larger fractions. Latent transition analysis showed that most children eventually adopted normative comparison strategies. Children who exhibited a partial understanding by choosing fractions with smaller numbers were more likely to adopt normative comparison strategies earlier than those with larger number biases. Controlling for general math achievement and other cognitive abilities, whole number line estimation accuracy predicted the probability of transitioning to normative comparison strategies. Exploratory factor analyses showed that over time, children appeared to increasingly represent fractions as discrete magnitudes when simpler strategies were unavailable. These results support the integrated theory of numerical development, which posits that an understanding of numbers as magnitudes unifies the process of learning whole numbers and fractions. The findings contrast with conceptual change theories, which propose that children must move from a view of numbers as counting units to a new view that accommodates fractions to overcome whole number bias. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Brief non-symbolic, approximate number practice enhances subsequent exact symbolic arithmetic in children

PubMed Central

Spelke, Elizabeth S.

2014-01-01

Recent research reveals a link between individual differences in mathematics achievement and performance on tasks that activate the approximate number system (ANS): a primitive cognitive system shared by diverse animal species and by humans of all ages. Here we used a brief experimental paradigm to test one causal hypothesis suggested by this relationship: activation of the ANS may enhance children's performance of symbolic arithmetic. Over 2 experiments, children who briefly practiced tasks that engaged primitive approximate numerical quantities performed better on subsequent exact, symbolic arithmetic problems than did children given other tasks involving comparison and manipulation of non-numerical magnitudes (brightness and length). The practice effect appeared specific to mathematics, as no differences between groups were observed on a comparable sentence completion task. These results move beyond correlational research and provide evidence that the exercise of non-symbolic numerical processes can enhance children's performance of symbolic mathematics. PMID:24462713

Developmental dyscalculia: compensatory mechanisms in left intraparietal regions in response to nonsymbolic magnitudes.

PubMed

Kaufmann, Liane; Vogel, Stephan E; Starke, Marc; Kremser, Christian; Schocke, Michael; Wood, Guilherme

2009-08-05

Functional magnetic resonance imaging (fMRI) studies investigating the neural mechanisms underlying developmental dyscalculia are scarce and results are thus far inconclusive. Main aim of the present study is to investigate the neural correlates of nonsymbolic number magnitude processing in children with and without dyscalculia. 18 children (9 with dyscalculia) were asked to solve a non-symbolic number magnitude comparison task (finger patterns) during brain scanning. For the spatial control task identical stimuli were employed, instructions varying only (judgment of palm rotation). This design enabled us to present identical stimuli with identical visual processing requirements in the experimental and the control task. Moreover, because numerical and spatial processing relies on parietal brain regions, task-specific contrasts are expected to reveal true number-specific activations. Behavioral results during scanning reveal that despite comparable (almost at ceiling) performance levels, task-specific activations were stronger in dyscalculic children in inferior parietal cortices bilaterally (intraparietal sulcus, supramarginal gyrus, extending to left angular gyrus). Interestingly, fMRI signal strengths reflected a group x task interaction: relative to baseline, controls produced significant deactivations in (intra)parietal regions bilaterally in response to number but not spatial processing, while the opposite pattern emerged in dyscalculics. Moreover, beta weights in response to number processing differed significantly between groups in left - but not right - (intra)parietal regions (becoming even positive in dyscalculic children). Overall, findings are suggestive of (a) less consistent neural activity in right (intra)parietal regions upon processing nonsymbolic number magnitudes; and (b) compensatory neural activity in left (intra)parietal regions in developmental dyscalculia.

Developmental dyscalculia: compensatory mechanisms in left intraparietal regions in response to nonsymbolic magnitudes

PubMed Central

Kaufmann, Liane; Vogel, Stephan E; Starke, Marc; Kremser, Christian; Schocke, Michael; Wood, Guilherme

2009-01-01

Background Functional magnetic resonance imaging (fMRI) studies investigating the neural mechanisms underlying developmental dyscalculia are scarce and results are thus far inconclusive. Main aim of the present study is to investigate the neural correlates of nonsymbolic number magnitude processing in children with and without dyscalculia. Methods 18 children (9 with dyscalculia) were asked to solve a non-symbolic number magnitude comparison task (finger patterns) during brain scanning. For the spatial control task identical stimuli were employed, instructions varying only (judgment of palm rotation). This design enabled us to present identical stimuli with identical visual processing requirements in the experimental and the control task. Moreover, because numerical and spatial processing relies on parietal brain regions, task-specific contrasts are expected to reveal true number-specific activations. Results Behavioral results during scanning reveal that despite comparable (almost at ceiling) performance levels, task-specific activations were stronger in dyscalculic children in inferior parietal cortices bilaterally (intraparietal sulcus, supramarginal gyrus, extending to left angular gyrus). Interestingly, fMRI signal strengths reflected a group × task interaction: relative to baseline, controls produced significant deactivations in (intra)parietal regions bilaterally in response to number but not spatial processing, while the opposite pattern emerged in dyscalculics. Moreover, beta weights in response to number processing differed significantly between groups in left – but not right – (intra)parietal regions (becoming even positive in dyscalculic children). Conclusion Overall, findings are suggestive of (a) less consistent neural activity in right (intra)parietal regions upon processing nonsymbolic number magnitudes; and (b) compensatory neural activity in left (intra)parietal regions in developmental dyscalculia. PMID:19653919

The effects of bilingual growth on toddlers’ executive function

PubMed Central

Crivello, Cristina; Kuzyk, Olivia; Rodrigues, Monyka; Friend, Margaret; Zesiger, Pascal; Poulin-Dubois, Diane

2015-01-01

The mastery of two languages provides bilingual speakers with cognitive benefits over monolinguals, particularly on cognitive flexibility and selective attention. However, extant research is limited to comparisons between monolinguals and bilinguals at a single point in time. This study investigated whether growth in bilingual proficiency, as shown by an increased number of translation equivalents (TEs) over a 7-month period, improves executive function. We hypothesized that bilingual toddlers with a larger increase of TEs would have more practice in switching across lexical systems, boosting executive function abilities. Expressive vocabulary and TEs were assessed at 24 and 31 months of age. A battery of tasks, including conflict, delay, and working memory tasks, was administered at 31 months. As expected, we observed a task-specific advantage in inhibitory control in bilinguals. More important, within the bilingual group, larger increases in the number of TEs predicted better performance on conflict tasks but not on delay tasks. This unique longitudinal design confirms the relation between executive function and early bilingualism. PMID:26402219

Text chat as a tool for referential questioning in Asperger syndrome.

PubMed

Rajendran, Gnanathusharan; Mitchell, Peter

2006-02-01

This article reports a study in which referential communication in 11 individuals with Asperger syndrome (AS) and 11 controls was compared between text chat and telephone, using a route-solving task. Participants deduced routes by asking closed questions, and the dependent variables were (a) accuracy in working out the route, (b) number of questions posed (turns taken), and (c) time taken to complete the task. Generally, individuals with AS were equally competent in solving the task in both media but less efficient than the typically developing comparison group. Individuals with AS who had higher measured executive ability adopted a similar approach to the comparison group, asking about landmarks on the map to deduce the route taken. In contrast, AS participants with lower executive ability used an inefficient left/right questioning strategy, which occupied more time, required more conversational turns, and was associated with a higher rate of error. Individuals with AS, who also have problems of executive functioning, may have difficulty communicating with others to use a route-solving task.

A Comparison of Techniques for Camera Selection and Hand-Off in a Video Network

NASA Astrophysics Data System (ADS)

Li, Yiming; Bhanu, Bir

Video networks are becoming increasingly important for solving many real-world problems. Multiple video sensors require collaboration when performing various tasks. One of the most basic tasks is the tracking of objects, which requires mechanisms to select a camera for a certain object and hand-off this object from one camera to another so as to accomplish seamless tracking. In this chapter, we provide a comprehensive comparison of current and emerging camera selection and hand-off techniques. We consider geometry-, statistics-, and game theory-based approaches and provide both theoretical and experimental comparison using centralized and distributed computational models. We provide simulation and experimental results using real data for various scenarios of a large number of cameras and objects for in-depth understanding of strengths and weaknesses of these techniques.

Numerical landmarks are useful--except when they're not.

PubMed

Siegler, Robert S; Thompson, Clarissa A

2014-04-01

Placing landmarks on number lines, such as marking each tenth on a 0-1 line with a hatch mark and the corresponding decimal, has been recommended as a useful tool for improving children's number sense. Four experiments indicated that some landmarks do have beneficial effects, others have harmful effects, and yet others have no effects on representations of common fractions (N/M). The effects of the landmarks were seen not only on the number line task where they appeared but also on a subsequent magnitude comparison task and on correlations with mathematics achievement tests. Landmarks appeared to exert their effects through the encodings and strategies that they promoted. Theoretical and educational implications are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Arithmetic processing in the brain shaped by cultures

PubMed Central

Tang, Yiyuan; Zhang, Wutian; Chen, Kewei; Feng, Shigang; Ji, Ye; Shen, Junxian; Reiman, Eric M.; Liu, Yijun

2006-01-01

The universal use of Arabic numbers in mathematics raises a question whether these digits are processed the same way in people speaking various languages, such as Chinese and English, which reflect differences in Eastern and Western cultures. Using functional MRI, we demonstrated a differential cortical representation of numbers between native Chinese and English speakers. Contrasting to native English speakers, who largely employ a language process that relies on the left perisylvian cortices for mental calculation such as a simple addition task, native Chinese speakers, instead, engage a visuo-premotor association network for the same task. Whereas in both groups the inferior parietal cortex was activated by a task for numerical quantity comparison, functional MRI connectivity analyses revealed a functional distinction between Chinese and English groups among the brain networks involved in the task. Our results further indicate that the different biological encoding of numbers may be shaped by visual reading experience during language acquisition and other cultural factors such as mathematics learning strategies and education systems, which cannot be explained completely by the differences in languages per se. PMID:16815966

Optimization of a Small-Scale Engine Using Plasma Enhanced Ignition

DTIC Science & Technology

2013-03-01

PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT...systems were tested in the small engine and their effects on engine performance determined through comparison with a regular spark discharge (thermal...pulse plasma discharge system purchased from Plasmatronics LLC. Air fuel ratio (λ units are used in this report) sweeps were performed at several

Logistics and Sampling Plan for Task 2: 1979-1980 IRS Comparison Study. Quality Control Analysis of Selected Aspects of Programs Administered by the Bureau of Student Financial Assistance.

ERIC Educational Resources Information Center

Walker, Gail; Kuchak, JoAnn

The type, number, and scope of errors on Basic Educational Opportunity Grant (BEOG) program applications were estimated in a replication of a 1976-1977 Internal Revenue Service (IRS) Comparison Study. Information reported on BEOG applicants and IRS income tax returns was compared for various categories of applicants. The study provides information…

Representations of numerical and non-numerical magnitude both contribute to mathematical competence in children.

PubMed

Lourenco, Stella F; Bonny, Justin W

2017-07-01

A growing body of evidence suggests that non-symbolic representations of number, which humans share with nonhuman animals, are functionally related to uniquely human mathematical thought. Other research suggesting that numerical and non-numerical magnitudes not only share analog format but also form part of a general magnitude system raises questions about whether the non-symbolic basis of mathematical thinking is unique to numerical magnitude. Here we examined this issue in 5- and 6-year-old children using comparison tasks of non-symbolic number arrays and cumulative area as well as standardized tests of math competence. One set of findings revealed that scores on both magnitude comparison tasks were modulated by ratio, consistent with shared analog format. Moreover, scores on these tasks were moderately correlated, suggesting overlap in the precision of numerical and non-numerical magnitudes, as expected under a general magnitude system. Another set of findings revealed that the precision of both types of magnitude contributed shared and unique variance to the same math measures (e.g. calculation and geometry), after accounting for age and verbal competence. These findings argue against an exclusive role for non-symbolic number in supporting early mathematical understanding. Moreover, they suggest that mathematical understanding may be rooted in a general system of magnitude representation that is not specific to numerical magnitude but that also encompasses non-numerical magnitude. © 2016 John Wiley & Sons Ltd.

Sequential or parallel decomposed processing of two-digit numbers? Evidence from eye-tracking.

PubMed

Moeller, Korbinian; Fischer, Martin H; Nuerk, Hans-Christoph; Willmes, Klaus

2009-02-01

While reaction time data have shown that decomposed processing of two-digit numbers occurs, there is little evidence about how decomposed processing functions. Poltrock and Schwartz (1984) argued that multi-digit numbers are compared in a sequential digit-by-digit fashion starting at the leftmost digit pair. In contrast, Nuerk and Willmes (2005) favoured parallel processing of the digits constituting a number. These models (i.e., sequential decomposition, parallel decomposition) make different predictions regarding the fixation pattern in a two-digit number magnitude comparison task and can therefore be differentiated by eye fixation data. We tested these models by evaluating participants' eye fixation behaviour while selecting the larger of two numbers. The stimulus set consisted of within-decade comparisons (e.g., 53_57) and between-decade comparisons (e.g., 42_57). The between-decade comparisons were further divided into compatible and incompatible trials (cf. Nuerk, Weger, & Willmes, 2001) and trials with different decade and unit distances. The observed fixation pattern implies that the comparison of two-digit numbers is not executed by sequentially comparing decade and unit digits as proposed by Poltrock and Schwartz (1984) but rather in a decomposed but parallel fashion. Moreover, the present fixation data provide first evidence that digit processing in multi-digit numbers is not a pure bottom-up effect, but is also influenced by top-down factors. Finally, implications for multi-digit number processing beyond the range of two-digit numbers are discussed.

The development of automated access to symbolic and non-symbolic number knowledge in children: an ERP study.

PubMed

Gebuis, Titia; Herfs, Inkeri K; Kenemans, J Leon; de Haan, Edward H F; van der Smagt, Maarten J

2009-11-01

Infants can visually detect changes in numerosity, which suggests that a (non-symbolic) numerosity system is already present early in life. This non-symbolic system is hypothesized to serve as the basis for the later acquired symbolic system. Little is known about the processes underlying the transition from the non-symbolic to symbolic code. In the current study we investigated the development of automatization of symbolic number processing in children from second (6.0 years) and fourth grade (8.0 years) and adults using a symbolic and non-symbolic size congruency task and event-related potentials (ERPs) as a measure. The comparison between symbolic and non-symbolic size congruency effects (SCEs) allowed us to disentangle processes necessary to perform the task from processes specific to numerosity notation. In contrast to previous studies, second graders already revealed a behavioral symbolic SCE similar to that of adults. In addition, the behavioral SCE increased for symbolic and decreased for non-symbolic notation with increasing age. For all age groups, the ERP data showed that the two magnitudes interfered at a level before selective activation of the response system, for both notations. However, only for the second graders distinct processes were recruited to perform the symbolic size comparison task. This shift in recruited processes for the symbolic task only might reflect the functional specialization of the parietal cortex.

The effect of visual parameters on neural activation during nonsymbolic number comparison and its relation to math competency.

PubMed

Wilkey, Eric D; Barone, Jordan C; Mazzocco, Michèle M M; Vogel, Stephan E; Price, Gavin R

2017-10-01

Nonsymbolic numerical comparison task performance (whereby a participant judges which of two groups of objects is numerically larger) is thought to index the efficiency of neural systems supporting numerical magnitude perception, and performance on such tasks has been related to individual differences in math competency. However, a growing body of research suggests task performance is heavily influenced by visual parameters of the stimuli (e.g. surface area and dot size of object sets) such that the correlation with math is driven by performance on trials in which number is incongruent with visual cues. Almost nothing is currently known about whether the neural correlates of nonsymbolic magnitude comparison are also affected by visual congruency. To investigate this issue, we used functional magnetic resonance imaging (fMRI) to analyze neural activity during a nonsymbolic comparison task as a function of visual congruency in a sample of typically developing high school students (n = 36). Further, we investigated the relation to math competency as measured by the preliminary scholastic aptitude test (PSAT) in 10th grade. Our results indicate that neural activity was modulated by the ratio of the dot sets being compared in brain regions previously shown to exhibit an effect of ratio (i.e. left anterior cingulate, left precentral gyrus, left intraparietal sulcus, and right superior parietal lobe) when calculated from the average of congruent and incongruent trials, as it is in most studies, and that the effect of ratio within those regions did not differ as a function of congruency condition. However, there were significant differences in other regions in overall task-related activation, as opposed to the neural ratio effect, when congruent and incongruent conditions were contrasted at the whole-brain level. Math competency negatively correlated with ratio-dependent neural response in the left insula across congruency conditions and showed distinct correlations when split across conditions. There was a positive correlation between math competency in the right supramarginal gyrus during congruent trials and a negative correlation in the left angular gyrus during incongruent trials. Together, these findings support the idea that performance on the nonsymbolic comparison task relates to math competency and ratio-dependent neural activity does not differ by congruency condition. With regards to math competency, congruent and incongruent trials showed distinct relations between math competency and individual differences in ratio-dependent neural activity. Copyright © 2017 Elsevier Inc. All rights reserved.

Laser light visual cueing for freezing of gait in Parkinson disease: A pilot study with male participants.

PubMed

Bunting-Perry, Lisette; Spindler, Meredith; Robinson, Keith M; Noorigian, Joseph; Cianci, Heather J; Duda, John E

2013-01-01

Freezing of gait (FOG) is a debilitating feature of Parkinson disease (PD). In this pilot study, we sought to assess the efficacy of a rolling walker with a laser beam visual cue to treat FOG in PD patients. We recruited 22 subjects with idiopathic PD who experienced on- and off-medication FOG. Subjects performed three walking tasks both with and without the laser beam while on medications. Outcome measures included time to complete tasks, number of steps, and number of FOG episodes. A crossover design allowed within-group comparisons between the two conditions. No significant differences were observed between the two walking conditions across the three tasks. The laser beam, when applied as a visual cue on a rolling walker, did not diminish FOG in this study.

Individual differences in the components of children's and adults' information processing for simple symbolic and non-symbolic numeric decisions.

PubMed

Thompson, Clarissa A; Ratcliff, Roger; McKoon, Gail

2016-10-01

How do speed and accuracy trade off, and what components of information processing develop as children and adults make simple numeric comparisons? Data from symbolic and non-symbolic number tasks were collected from 19 first graders (Mage=7.12 years), 26 second/third graders (Mage=8.20 years), 27 fourth/fifth graders (Mage=10.46 years), and 19 seventh/eighth graders (Mage=13.22 years). The non-symbolic task asked children to decide whether an array of asterisks had a larger or smaller number than 50, and the symbolic task asked whether a two-digit number was greater than or less than 50. We used a diffusion model analysis to estimate components of processing in tasks from accuracy, correct and error response times, and response time (RT) distributions. Participants who were accurate on one task were accurate on the other task, and participants who made fast decisions on one task made fast decisions on the other task. Older participants extracted a higher quality of information from the stimulus arrays, were more willing to make a decision, and were faster at encoding, transforming the stimulus representation, and executing their responses. Individual participants' accuracy and RTs were uncorrelated. Drift rate and boundary settings were significantly related across tasks, but they were unrelated to each other. Accuracy was mainly determined by drift rate, and RT was mainly determined by boundary separation. We concluded that RT and accuracy operate largely independently. Copyright © 2016 Elsevier Inc. All rights reserved.

Use of B-Spline in the Finite Element Analysis: Comparison with ANCF Geometry

DTIC Science & Technology

2011-02-04

Beam Elements”, Multibody System Dynamics , Vol. 20 (1), pp. 1-28. 7. Hamed, A.M., Shabana, A.A., Jayakumar , P., and Letherwood, M.D., 2011 “Non...West Taylor Street Chicago, Illinois 60607 Paramsothy Jayakumar Michael D. Letherwood U.S. Army RDECOM-TARDEC 6501 E. 11 Mile Road Warren...Ashraf Hamed; Abdel - Nasser Mohamed; Paramsothy Jayakumar ; Michael Letherwood 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7

Nonsymbolic number and cumulative area representations contribute shared and unique variance to symbolic math competence

PubMed Central

Lourenco, Stella F.; Bonny, Justin W.; Fernandez, Edmund P.; Rao, Sonia

2012-01-01

Humans and nonhuman animals share the capacity to estimate, without counting, the number of objects in a set by relying on an approximate number system (ANS). Only humans, however, learn the concepts and operations of symbolic mathematics. Despite vast differences between these two systems of quantification, neural and behavioral findings suggest functional connections. Another line of research suggests that the ANS is part of a larger, more general system of magnitude representation. Reports of cognitive interactions and common neural coding for number and other magnitudes such as spatial extent led us to ask whether, and how, nonnumerical magnitude interfaces with mathematical competence. On two magnitude comparison tasks, college students estimated (without counting or explicit calculation) which of two arrays was greater in number or cumulative area. They also completed a battery of standardized math tests. Individual differences in both number and cumulative area precision (measured by accuracy on the magnitude comparison tasks) correlated with interindividual variability in math competence, particularly advanced arithmetic and geometry, even after accounting for general aspects of intelligence. Moreover, analyses revealed that whereas number precision contributed unique variance to advanced arithmetic, cumulative area precision contributed unique variance to geometry. Taken together, these results provide evidence for shared and unique contributions of nonsymbolic number and cumulative area representations to formally taught mathematics. More broadly, they suggest that uniquely human branches of mathematics interface with an evolutionarily primitive general magnitude system, which includes partially overlapping representations of numerical and nonnumerical magnitude. PMID:23091023

The number of functional olfactory receptor genes and the relative size of olfactory brain structures are poor predictors of olfactory discrimination performance with enantiomers.

PubMed

Laska, Matthias; Genzel, Daria; Wieser, Alexandra

2005-02-01

The ability of four squirrel monkeys and three pigtail macaques to distinguish between nine enantiomeric odor pairs sharing an isopropenyl group at the chiral center was investigated in terms of a conditioning paradigm. All animals from both species were able to discriminate between the optical isomers of limonene, carvone, dihydrocarvone, dihydrocarveole and dihydrocarvyl acetate, whereas they failed to distinguish between the (+)- and (-)-forms of perillaaldehyde and limonene oxide. The pigtail macaques, but not the squirrel monkeys, also discriminated between the antipodes of perillaalcohol and isopulegol. A comparison of the across-task patterns of discrimination performance shows a high degree of similarity among the two primate species and also between these nonhuman primates and human subjects tested in an earlier study on the same tasks. These findings suggest that between-species comparisons of the relative size of olfactory brain structures or of the number of functional olfactory receptor genes are poor predictors of olfactory discrimination performance with enantiomers.

Comparisons of population subgroups performance on a keyboard psychomotor task

NASA Technical Reports Server (NTRS)

Stapleford, R. L.

1973-01-01

Response time and pass/fail data were obtained from 163 subjects performing a psychomotor task. The basic task comprised a random five digit number briefly displayed to the subject at the start of each trail, and the keyboard on which the subject was to enter the number as fast as he could accurately do so after the display was extinguished. Some tests were run with the addition of a secondary task which required the subject to respond to a displayed light appearing at a random time. Matched pairs of subjects were selected from the group to analyze the effects of age, sex, intelligence, prior keyboard skill, and drinking habits. There was little or no effect due to age or drinking habits. Differences in response time were: average IQ subjects faster than low IQ subjects by 0.5 to 0.6 sec; subjects with prior keyboard skill faster by 0.4 to 0.5 sec; and female subjects faster by 0.2 to 0.3 sec. These effects were generally insensitive to the presence of the secondary task.

The contribution of general cognitive abilities and number abilities to different aspects of mathematics in children.

PubMed

Träff, Ulf

2013-10-01

This study examined the relative contributions of general cognitive abilities and number abilities to word problem solving, calculation, and arithmetic fact retrieval in a sample of 134 children aged 10 to 13 years. The following tasks were administered: listening span, visual matrix span, verbal fluency, color naming, Raven's Progressive Matrices, enumeration, number line estimation, and digit comparison. Hierarchical multiple regressions demonstrated that number abilities provided an independent contribution to fact retrieval and word problem solving. General cognitive abilities contributed to problem solving and calculation. All three number tasks accounted for a similar amount of variance in fact retrieval, whereas only the number line estimation task contributed unique variance in word problem solving. Verbal fluency and Raven's matrices accounted for an equal amount of variance in problem solving and calculation. The current findings demonstrate, in accordance with Fuchs and colleagues' developmental model of mathematical learning (Developmental Psychology, 2010, Vol. 46, pp. 1731-1746), that both number abilities and general cognitive abilities underlie 10- to 13-year-olds' proficiency in problem solving, whereas only number abilities underlie arithmetic fact retrieval. Thus, the amount and type of cognitive contribution to arithmetic proficiency varies between the different aspects of arithmetic. Furthermore, how closely linked a specific aspect of arithmetic is to the whole number representation systems is not the only factor determining the amount and type of cognitive contribution in 10- to 13-year-olds. In addition, the mathematical complexity of the task appears to influence the amount and type of cognitive support. Copyright © 2013 Elsevier Inc. All rights reserved.

Differences in arithmetic performance between Chinese and German adults are accompanied by differences in processing of non-symbolic numerical magnitude

PubMed Central

Lonnemann, Jan; Li, Su; Zhao, Pei; Li, Peng; Linkersdörfer, Janosch; Lindberg, Sven; Hasselhorn, Marcus; Yan, Song

2017-01-01

Human beings are assumed to possess an approximate number system (ANS) dedicated to extracting and representing approximate numerical magnitude information. The ANS is assumed to be fundamental to arithmetic learning and has been shown to be associated with arithmetic performance. It is, however, still a matter of debate whether better arithmetic skills are reflected in the ANS. To address this issue, Chinese and German adults were compared regarding their performance in simple arithmetic tasks and in a non-symbolic numerical magnitude comparison task. Chinese participants showed a better performance in solving simple arithmetic tasks and faster reaction times in the non-symbolic numerical magnitude comparison task without making more errors than their German peers. These differences in performance could not be ascribed to differences in general cognitive abilities. Better arithmetic skills were thus found to be accompanied by a higher speed of retrieving non-symbolic numerical magnitude knowledge but not by a higher precision of non-symbolic numerical magnitude representations. The group difference in the speed of retrieving non-symbolic numerical magnitude knowledge was fully mediated by the performance in arithmetic tasks, suggesting that arithmetic skills shape non-symbolic numerical magnitude processing skills. PMID:28384191

Longitudinal changes in everyday life after home modifications for people aging with disabilities.

PubMed

Petersson, Ingela; Kottorp, Anders; Bergström, Jakob; Lilja, Margareta

2009-05-01

To investigate longitudinal impacts of home modifications on the difficulty of performing everyday life tasks for people aging with disabilities, and to investigate whether other factors had any additional impacts on difficulty in everyday life tasks for people receiving home modifications. The sample consisted of 103 persons aging with disabilities and in need of home modifications, divided into an intervention group and a comparison group. The data were first subjected to Rasch analysis and a random coefficient model was used. Participants in the intervention group reported a significantly lower level of difficulty in everyday life tasks compared with those in the comparison group. One confounding factor, number of months waiting for home modification, had an impact on difficulty in everyday life. Home modifications are effective in decreasing difficulty in performing everyday life tasks up to six months after the installation. Furthermore, to be effective home modifications need to be installed in a timely fashion. For each consecutive month the person waited for their home modification the difficulty of performing everyday life tasks increased. Therefore, it is important that home modifications be installed as soon as possible after the need has been identified.

Magnitude comparison with different types of rational numbers.

PubMed

DeWolf, Melissa; Grounds, Margaret A; Bassok, Miriam; Holyoak, Keith J

2014-02-01

An important issue in understanding mathematical cognition involves the similarities and differences between the magnitude representations associated with various types of rational numbers. For single-digit integers, evidence indicates that magnitudes are represented as analog values on a mental number line, such that magnitude comparisons are made more quickly and accurately as the numerical distance between numbers increases (the distance effect). Evidence concerning a distance effect for compositional numbers (e.g., multidigit whole numbers, fractions and decimals) is mixed. We compared the patterns of response times and errors for college students in magnitude comparison tasks across closely matched sets of rational numbers (e.g., 22/37, 0.595, 595). In Experiment 1, a distance effect was found for both fractions and decimals, but response times were dramatically slower for fractions than for decimals. Experiments 2 and 3 compared performance across fractions, decimals, and 3-digit integers. Response patterns for decimals and integers were extremely similar but, as in Experiment 1, magnitude comparisons based on fractions were dramatically slower, even when the decimals varied in precision (i.e., number of place digits) and could not be compared in the same way as multidigit integers (Experiment 3). Our findings indicate that comparisons of all three types of numbers exhibit a distance effect, but that processing often involves strategic focus on components of numbers. Fractions impose an especially high processing burden due to their bipartite (a/b) structure. In contrast to the other number types, the magnitude values associated with fractions appear to be less precise, and more dependent on explicit calculation. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Comparative assessment of laparoscopic single-site surgery instruments to conventional laparoscopic in laboratory setting.

PubMed

Stolzenburg, Jens-Uwe; Kallidonis, Panagiotis; Oh, Min-A; Ghulam, Nabi; Do, Minh; Haefner, Tim; Dietel, Anja; Till, Holger; Sakellaropoulos, George; Liatsikos, Evangelos N

2010-02-01

Laparoendoscopic single-site surgery (LESS) represents the latest innovation in laparoscopic surgery. We compare in dry and animal laboratory the efficacy of recently introduced pre-bent instruments with conventional laparoscopic and flexible instruments in terms of time requirement, maneuverability, and ease of handling. Participants of varying laparoscopic experience were included in the study and divided in groups according to their experience. The participants performed predetermined tasks in dry laboratory using all sets of instruments. An experienced laparoscopic surgeon performed 24 nephrectomies in 12 pigs using all sets of instruments. Single port was used for all instrument sets except for the conventional instruments, which were inserted through three ports. The time required for the performance of dry laboratory tasks and the porcine nephrectomies was recorded. Errors in the performance of dry laboratory tasks of each instrument type were also recorded. Pre-bent instruments had a significant advantage over flexible instruments in terms of time requirement to accomplish tasks and procedures as well as maneuverability. Flexible instruments were more time consuming in comparison to the conventional laparoscopic instruments during the performance of the tasks. There were no significant differences in the time required for the accomplishment of dry laboratory tasks or steps of nephrectomy using conventional instruments through appropriate number of ports in comparison to pre-bent instruments through single port. Pre-bent instruments were less time consuming and with better maneuverability in comparison to flexible instruments in experimental single-port access surgery. Further clinical investigations would elucidate the efficacy of pre-bent instruments.

Language affects symbolic arithmetic in children: the case of number word inversion.

PubMed

Göbel, Silke M; Moeller, Korbinian; Pixner, Silvia; Kaufmann, Liane; Nuerk, Hans-Christoph

2014-03-01

Specific language influences have been observed in basic numerical tasks such as magnitude comparison, transcoding, and the number line estimation task. However, so far language influences in more complex calculations have not been reported in children. In this translingual study, 7- to 9-year-old German- and Italian-speaking children were tested on a symbolic addition task. Whereas the order of tens and units in Italian number words follows the order of the Arabic notation, the order is inverted in German number words. For both language groups, addition problems were more difficult when a carry operation was needed, that is, when a manipulation within the place-value structure of the Arabic number system was particularly important. Most important, this carry effect was more pronounced in response latencies for children speaking German, a language with inverted verbal mapping of the place-value structure. In addition, independent of language group, the size of the carry effect was significantly related to verbal working memory. The current study indicates that symbolic arithmetic and the carry effect in particular are modulated by language-specific characteristics. Our results underline the fact that the structure of the language of instruction is an important factor in children's mathematical education and needs to be taken into account even for seemingly nonverbal symbolic Arabic tasks. Copyright © 2013 Elsevier Inc. All rights reserved.

A Constructive Neural-Network Approach to Modeling Psychological Development

ERIC Educational Resources Information Center

Shultz, Thomas R.

2012-01-01

This article reviews a particular computational modeling approach to the study of psychological development--that of constructive neural networks. This approach is applied to a variety of developmental domains and issues, including Piagetian tasks, shift learning, language acquisition, number comparison, habituation of visual attention, concept…

Individual differences influence two-digit number processing, but not their analog magnitude processing: a large-scale online study.

PubMed

Huber, Stefan; Nuerk, Hans-Christoph; Reips, Ulf-Dietrich; Soltanlou, Mojtaba

2017-12-23

Symbolic magnitude comparison is one of the most well-studied cognitive processes in research on numerical cognition. However, while the cognitive mechanisms of symbolic magnitude processing have been intensively studied, previous studies have paid less attention to individual differences influencing symbolic magnitude comparison. Employing a two-digit number comparison task in an online setting, we replicated previous effects, including the distance effect, the unit-decade compatibility effect, and the effect of cognitive control on the adaptation to filler items, in a large-scale study in 452 adults. Additionally, we observed that the most influential individual differences were participants' first language, time spent playing computer games and gender, followed by reported alcohol consumption, age and mathematical ability. Participants who used a first language with a left-to-right reading/writing direction were faster than those who read and wrote in the right-to-left direction. Reported playing time for computer games was correlated with faster reaction times. Female participants showed slower reaction times and a larger unit-decade compatibility effect than male participants. Participants who reported never consuming alcohol showed overall slower response times than others. Older participants were slower, but more accurate. Finally, higher grades in mathematics were associated with faster reaction times. We conclude that typical experiments on numerical cognition that employ a keyboard as an input device can also be run in an online setting. Moreover, while individual differences have no influence on domain-specific magnitude processing-apart from age, which increases the decade distance effect-they generally influence performance on a two-digit number comparison task.

Numerical aerodynamic simulation facility preliminary study, volume 2 and appendices

NASA Technical Reports Server (NTRS)

1977-01-01

Data to support results obtained in technology assessment studies are presented. Objectives, starting points, and future study tasks are outlined. Key design issues discussed in appendices include: data allocation, transposition network design, fault tolerance and trustworthiness, logic design, processing element of existing components, number of processors, the host system, alternate data base memory designs, number representation, fast div 521 instruction, architectures, and lockstep array versus synchronizable array machine comparison.

Blood Biomarker Profile of TBI Associated Cognitive Impairment Among Old and Young Veterans

DTIC Science & Technology

2016-10-01

INVESTIGATOR: Kristine Yaffe, MD CONTRACTING ORGANIZATION: Northern California Institute for Research and Education San Francisco, CA 94121 REPORT...MD 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Northern California Institute for Research and Education ...and Resiliency for Dementia: Comparison of Male and Female Veterans (Yaffe: PI) Time Commitment: 1.2 calendar months Supporting Agency: DOD

Comparing capacity coefficient and dual task assessment of visual multitasking workload

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

Blaha, Leslie M.

Capacity coefficient analysis could offer a theoretically grounded alternative approach to subjective measures and dual task assessment of cognitive workload. Workload capacity or workload efficiency is a human information processing modeling construct defined as the amount of information that can be processed by the visual cognitive system given a specified of amount of time. In this paper, I explore the relationship between capacity coefficient analysis of workload efficiency and dual task response time measures. To capture multitasking performance, I examine how the relatively simple assumptions underlying the capacity construct generalize beyond the single visual decision making tasks. The fundamental toolsmore » for measuring workload efficiency are the integrated hazard and reverse hazard functions of response times, which are defined by log transforms of the response time distribution. These functions are used in the capacity coefficient analysis to provide a functional assessment of the amount of work completed by the cognitive system over the entire range of response times. For the study of visual multitasking, capacity coefficient analysis enables a comparison of visual information throughput as the number of tasks increases from one to two to any number of simultaneous tasks. I illustrate the use of capacity coefficients for visual multitasking on sample data from dynamic multitasking in the modified Multi-attribute Task Battery.« less

Early Numeracy Assessment: The Development of the Preschool Numeracy Scales

PubMed Central

Purpura, David J.; Lonigan, Christopher J.

2015-01-01

Research Findings The focus of this study was to construct and validate twelve brief early numeracy assessment tasks that measure the skills and concepts identified as key to early mathematics development by the National Council of Teachers of Mathematics (2006) and the National Mathematics Advisory Panel (2008)—as well as critical developmental precursors to later mathematics skill by the Common Core State Standards (CCSS; 2010). Participants were 393 preschool children ages 3 to 5 years old. Measure development and validation occurred through three analytic phases designed to ensure that the measures were brief, reliable, and valid. These measures included: one-to-one counting, cardinality, counting subsets, subitizing, number comparison, set comparison, number order, numeral identification, set-to-numerals, story problems, number combinations, and verbal counting. Practice or Policy Teachers have extensive demands on their time, yet, they are tasked with ensuring that all students’ academic needs are met. To identify individual instructional needs and measure progress, they need to be able to efficiently assess children’s numeracy skills. The measures developed in this study are not only reliable and valid, but also easy to use and can be utilized for measuring the effects of targeted instruction on individual numeracy skills. PMID:25709375

Development of numerical processing in children with typical and dyscalculic arithmetic skills—a longitudinal study

PubMed Central

Landerl, Karin

2013-01-01

Numerical processing has been demonstrated to be closely associated with arithmetic skills, however, our knowledge on the development of the relevant cognitive mechanisms is limited. The present longitudinal study investigated the developmental trajectories of numerical processing in 42 children with age-adequate arithmetic development and 41 children with dyscalculia over a 2-year period from beginning of Grade 2, when children were 7; 6 years old, to beginning of Grade 4. A battery of numerical processing tasks (dot enumeration, non-symbolic and symbolic comparison of one- and two-digit numbers, physical comparison, number line estimation) was given five times during the study (beginning and middle of each school year). Efficiency of numerical processing was a very good indicator of development in numerical processing while within-task effects remained largely constant and showed low long-term stability before middle of Grade 3. Children with dyscalculia showed less efficient numerical processing reflected in specifically prolonged response times. Importantly, they showed consistently larger slopes for dot enumeration in the subitizing range, an untypically large compatibility effect when processing two-digit numbers, and they were consistently less accurate in placing numbers on a number line. Thus, we were able to identify parameters that can be used in future research to characterize numerical processing in typical and dyscalculic development. These parameters can also be helpful for identification of children who struggle in their numerical development. PMID:23898310

Basic and Exceptional Calculation Abilities in a Calculating Prodigy: A Case Study.

ERIC Educational Resources Information Center

Pesenti, Mauro; Seron, Xavier; Samson, Dana; Duroux, Bruno

1999-01-01

Describes the basic and exceptional calculation abilities of a calculating prodigy whose performances were investigated in single- and multi-digit number multiplication, numerical comparison, raising of powers, and short-term memory tasks. Shows how his highly efficient long-term memory storage and retrieval processes, knowledge of calculation…

Children's Early Numeracy in Finland and Iran

ERIC Educational Resources Information Center

Aunio, Pirjo; Korhonen, Johan; Bashash, Laaya; Khoshbakht, Fariba

2014-01-01

This research investigates similarities and differences in young children's early numeracy skills related to age, nationality and gender. The participants were five- to seven-year-old children from Finland and Iran. Early numeracy was investigated by using tasks measuring number-related relational skills (e.g. comparison, one-to-one…

CoCoNUT: an efficient system for the comparison and analysis of genomes

PubMed Central

2008-01-01

Background Comparative genomics is the analysis and comparison of genomes from different species. This area of research is driven by the large number of sequenced genomes and heavily relies on efficient algorithms and software to perform pairwise and multiple genome comparisons. Results Most of the software tools available are tailored for one specific task. In contrast, we have developed a novel system CoCoNUT (Computational Comparative geNomics Utility Toolkit) that allows solving several different tasks in a unified framework: (1) finding regions of high similarity among multiple genomic sequences and aligning them, (2) comparing two draft or multi-chromosomal genomes, (3) locating large segmental duplications in large genomic sequences, and (4) mapping cDNA/EST to genomic sequences. Conclusion CoCoNUT is competitive with other software tools w.r.t. the quality of the results. The use of state of the art algorithms and data structures allows CoCoNUT to solve comparative genomics tasks more efficiently than previous tools. With the improved user interface (including an interactive visualization component), CoCoNUT provides a unified, versatile, and easy-to-use software tool for large scale studies in comparative genomics. PMID:19014477

Identity matching in a patient with Alzheimer's disease.

PubMed

Steinunn Steingrimsdottir, Hanna; Arntzen, Erik

2011-05-01

Difficulties with short-term memory are one of the main problems in patients with dementia. Therefore, one purpose of this study was to examine the effects of simultaneous vs delayed presentation of comparison stimuli in a matching-to-sample (MTS) task using computerized training. By using an identity MTS procedure, the participant was trained to select a comparison stimulus identical to a sample stimulus. A 2nd purpose was to study the effect of the number of choices presented, thereby evaluating short-term memory deficits and possible deterioration of deficits over time. In this study, an 80-year-old-male with a Mini-Mental State Examination (MMSE) score of 10 was exposed to 4 experimental conditions. The results showed that using 3 comparison stimuli presented simultaneously with the sample stimulus on the screen resulted in more incorrect responding than when using 2 comparison stimuli. Furthermore, when adding a 0-second delay between the presentation of the sample stimulus and the 2 comparison stimuli, the number of correct responses did not exceed chance level.

Frequency of Home Numeracy Activities Is Differentially Related to Basic Number Processing and Calculation Skills in Kindergartners.

PubMed

Mutaf Yıldız, Belde; Sasanguie, Delphine; De Smedt, Bert; Reynvoet, Bert

2018-01-01

Home numeracy has been shown to play an important role in children's mathematical performance. However, findings are inconsistent as to which home numeracy activities are related to which mathematical skills. The present study disentangled between various mathematical abilities that were previously masked by the use of composite scores of mathematical achievement. Our aim was to shed light on the specific associations between home numeracy and various mathematical abilities. The relationships between kindergartners' home numeracy activities, their basic number processing and calculation skills were investigated. Participants were 128 kindergartners ( M age = 5.43 years, SD = 0.29, range: 4.88-6.02 years) and their parents. The children completed non-symbolic and symbolic comparison tasks, non-symbolic and symbolic number line estimation tasks, mapping tasks (enumeration and connecting), and two calculation tasks. Their parents completed a home numeracy questionnaire. Results indicated small but significant associations between formal home numeracy activities that involved more explicit teaching efforts (i.e., identifying numerals, counting) and children's enumeration skills. There was no correlation between formal home numeracy activities and non-symbolic number processing. Informal home numeracy activities that involved more implicit teaching attempts , such as "playing games" and "using numbers in daily life," were (weakly) correlated with calculation and symbolic number line estimation, respectively. The present findings suggest that disentangling between various basic number processing and calculation skills in children might unravel specific relations with both formal and informal home numeracy activities. This might explain earlier reported contradictory findings on the association between home numeracy and mathematical abilities.

Frequency of Home Numeracy Activities Is Differentially Related to Basic Number Processing and Calculation Skills in Kindergartners

PubMed Central

Mutaf Yıldız, Belde; Sasanguie, Delphine; De Smedt, Bert; Reynvoet, Bert

2018-01-01

Home numeracy has been shown to play an important role in children’s mathematical performance. However, findings are inconsistent as to which home numeracy activities are related to which mathematical skills. The present study disentangled between various mathematical abilities that were previously masked by the use of composite scores of mathematical achievement. Our aim was to shed light on the specific associations between home numeracy and various mathematical abilities. The relationships between kindergartners’ home numeracy activities, their basic number processing and calculation skills were investigated. Participants were 128 kindergartners (Mage = 5.43 years, SD = 0.29, range: 4.88–6.02 years) and their parents. The children completed non-symbolic and symbolic comparison tasks, non-symbolic and symbolic number line estimation tasks, mapping tasks (enumeration and connecting), and two calculation tasks. Their parents completed a home numeracy questionnaire. Results indicated small but significant associations between formal home numeracy activities that involved more explicit teaching efforts (i.e., identifying numerals, counting) and children’s enumeration skills. There was no correlation between formal home numeracy activities and non-symbolic number processing. Informal home numeracy activities that involved more implicit teaching attempts, such as “playing games” and “using numbers in daily life,” were (weakly) correlated with calculation and symbolic number line estimation, respectively. The present findings suggest that disentangling between various basic number processing and calculation skills in children might unravel specific relations with both formal and informal home numeracy activities. This might explain earlier reported contradictory findings on the association between home numeracy and mathematical abilities. PMID:29623055

Dynamic sequence analysis of a decision making task of multielement target tracking and its usage as a learning method

NASA Astrophysics Data System (ADS)

Kang, Ziho

This dissertation is divided into four parts: 1) Development of effective methods for comparing visual scanning paths (or scanpaths) for a dynamic task of multiple moving targets, 2) application of the methods to compare the scanpaths of experts and novices for a conflict detection task of multiple aircraft on radar screen, 3) a post-hoc analysis of other eye movement characteristics of experts and novices, and 4) finding out whether the scanpaths of experts can be used to teach the novices. In order to compare experts' and novices' scanpaths, two methods are developed. The first proposed method is the matrix comparisons using the Mantel test. The second proposed method is the maximum transition-based agglomerative hierarchical clustering (MTAHC) where comparisons of multi-level visual groupings are held out. The matrix comparison method was useful for a small number of targets during the preliminary experiment, but turned out to be inapplicable to a realistic case when tens of aircraft were presented on screen; however, MTAHC was effective with large number of aircraft on screen. The experiments with experts and novices on the aircraft conflict detection task showed that their scanpaths are different. The MTAHC result was able to explicitly show how experts visually grouped multiple aircraft based on similar altitudes while novices tended to group them based on convergence. Also, the MTAHC results showed that novices paid much attention to the converging aircraft groups even if they are safely separated by altitude; therefore, less attention was given to the actual conflicting pairs resulting in low correct conflict detection rates. Since the analysis showed the scanpath differences, experts' scanpaths were shown to novices in order to find out its effectiveness. The scanpath treatment group showed indications that they changed their visual movements from trajectory-based to altitude-based movements. Between the treatment and the non-treatment group, there were no significant differences in terms of number of correct detections; however, the treatment group made significantly fewer false alarms.

Rankings, Standards, and Competition: Task vs. Scale Comparisons

ERIC Educational Resources Information Center

Garcia, Stephen M.; Tor, Avishalom

2007-01-01

Research showing how upward social comparison breeds competitive behavior has so far conflated local comparisons in "task" performance (e.g. a test score) with comparisons on a more general "scale" (i.e. an underlying skill). Using a ranking methodology (Garcia, Tor, & Gonzalez, 2006) to separate task and scale comparisons, Studies 1-2 reveal that…

A meta-analysis of math performance in Turner syndrome.

PubMed

Baker, Joseph M; Reiss, Allan L

2016-02-01

Studies investigating the relationship between Turner syndrome and math learning disability have used a wide variation of tasks designed to test various aspects of mathematical competencies. Although these studies have revealed much about the math deficits common to Turner syndrome, their diversity makes comparisons between individual studies difficult. As a result, the consistency of outcomes among these diverse measures remains unknown. The overarching aim of this review is to provide a systematic meta-analysis of the differences in math and number performance between females with Turner syndrome and age-matched neurotypical peers. We provide a meta-analysis of behavioral performance in Turner syndrome relative to age-matched neurotypical populations on assessments of math and number aptitude. In total, 112 comparisons collected across 17 studies were included. Although 54% of all statistical comparisons in our analyses failed to reject the null hypothesis, our results indicate that meaningful group differences exist on all comparisons except those that do not require explicit calculation. Taken together, these results help elucidate our current understanding of math and number weaknesses in Turner syndrome, while highlighting specific topics that require further investigation. © 2015 Mac Keith Press.

Eye movements reflect and shape strategies in fraction comparison.

PubMed

Ischebeck, Anja; Weilharter, Marina; Körner, Christof

2016-01-01

The comparison of fractions is a difficult task that can often be facilitated by separately comparing components (numerators and denominators) of the fractions--that is, by applying so-called component-based strategies. The usefulness of such strategies depends on the type of fraction pair to be compared. We investigated the temporal organization and the flexibility of strategy deployment in fraction comparison by evaluating sequences of eye movements in 20 young adults. We found that component-based strategies could account for the response times and the overall number of fixations observed for the different fraction pairs. The analysis of eye movement sequences showed that the initial eye movements in a trial were characterized by stereotypical scanning patterns indicative of an exploratory phase that served to establish the kind of fraction pair presented. Eye movements that followed this phase adapted to the particular type of fraction pair and indicated the deployment of specific comparison strategies. These results demonstrate that participants employ eye movements systematically to support strategy use in fraction comparison. Participants showed a remarkable flexibility to adapt to the most efficient strategy on a trial-by-trial basis. Our results confirm the value of eye movement measurements in the exploration of strategic adaptation in complex tasks.

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

PubMed

File, S E

1992-01-01

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

A case study of arithmetic facts dyscalculia caused by a hypersensitivity-to-interference in memory.

PubMed

De Visscher, Alice; Noël, Marie-Pascale

2013-01-01

While the heterogeneity of developmental dyscalculia is increasingly recognized, the different profiles have not yet been clearly established. Among the features underpinning types of developmental dyscalculia suggested in the literature, an impairment in arithmetic fact retrieval is particularly prominent. In this paper, we present a case study of an adult woman (DB) with very good cognitive capacities suffering from a specific and developmental arithmetic fact retrieval deficit. We test the main hypotheses about developmental dyscalculia derived from literature. We first explore the influential hypothesis of an approximate number system deficit, through estimation tasks, comparison tasks and a priming comparison task. Secondly, we evaluate whether DB's mathematical deficiencies are caused by a rote verbal memory deficit, using tasks involving completion of expressions, and reciting automatic series such as the alphabet and the months of the year. Alternatively, taking into account the extreme similarity of the arithmetic facts, we propose that a heightened sensitivity to interference could have prevented DB from memorizing the arithmetic facts. The pattern of DB's results on different tasks supports this hypothesis. Our findings identify a new etiology of a specific impairment of arithmetic facts storage, namely a hypersensitivity-to-interference. Copyright © 2012 Elsevier Ltd. All rights reserved.

Modelling of non-equilibrium flow in the branched pipeline systems

NASA Astrophysics Data System (ADS)

Sumskoi, S. I.; Sverchkov, A. M.; Lisanov, M. V.; Egorov, A. F.

2016-09-01

This article presents a mathematical model and a numerical method for solving the task of water hammer in the branched pipeline system. The task is considered in the onedimensional non-stationary formulation taking into account the realities such as the change in the diameter of the pipeline and its branches. By comparison with the existing analytic solution it has been shown that the proposed method possesses good accuracy. With the help of the developed model and numerical method the task has been solved concerning the transmission of the compression waves complex in the branching pipeline system when several shut down valves operate. It should be noted that the offered model and method may be easily introduced to a number of other tasks, for example, to describe the flow of blood in the vessels.

Number-specific and general cognitive markers of preschoolers' math ability profiles.

PubMed

Gray, Sarah A; Reeve, Robert A

2016-07-01

Different number-specific and general cognitive markers have been claimed to underlie preschoolers' math ability. It is unclear, however, whether similar/different cognitive markers, or combinations of them, are associated with different patterns of emerging math abilities (i.e., different patterns of strength and weakness). To examine this question, 103 preschoolers (40-60 months of age) completed six math tasks (count sequence, object counting, give a number, naming numbers, ordinal relations, and arithmetic), three number-specific markers of math ability (dot enumeration, magnitude comparison, and spontaneous focusing on numerosity), and four general markers (working memory, response inhibition, attention, and vocabulary). A three-step latent profile modeling procedure identified five math ability profiles that differed in their patterns of math strengths and weaknesses; specifically, the profiles were characterized by (a) excellent math ability on all math tasks, (b) good arithmetic ability, (c) good math ability but relatively poor count sequence recitation ability, (d) average ability on all math tasks, and (e) poor ability on all math tasks. After controlling for age, only dot enumeration and spontaneous focusing on numerosity were associated with the math ability profiles, whereas vocabulary was also marginally significant, and these markers were differentially associated with different profiles; that is, different cognitive markers were associated with different patterns of strengths and weaknesses in math abilities. Findings are discussed in terms of their implications for the development of math cognition. Copyright © 2016 Elsevier Inc. All rights reserved.

Between-individual comparisons in performance evaluation: a perspective from prospect theory.

PubMed

Wong, Kin Fai Ellick; Kwong, Jessica Y Y

2005-03-01

This article examines how between-individual comparisons influence performance evaluations in rating tasks. The authors demonstrated a systematic change in the perceived difference across ratees as a result of changing the way performance information is expressed. Study 1 found that perceived performance difference between 2 individuals was greater when their objective performance levels were presented with small numbers (e.g., absence rates of 2% vs. 5%) than when they were presented with large numbers (e.g., attendance rates of 98% vs. 95%). Extending this finding to situations involving trade-offs between multiple performance attributes across ratees, Study 2 showed that the relative preference for 1 ratee over another actually reversed when the presentation format of the performance information changed. The authors draw upon prospect theory to offer a theoretical framework describing the between-individual comparison aspect of performance evaluation.

Symbolic and non-symbolic number magnitude processing in children with developmental dyscalculia.

PubMed

Castro Cañizares, Danilka; Reigosa Crespo, Vivian; González Alemañy, Eduardo

2012-11-01

The aim of this study was to evaluate if children with Developmental Dyscalculia (DD) exhibit a general deficit in magnitude representations or a specific deficit in the connection of symbolic representations with the corresponding analogous magnitudes. DD was diagnosed using a timed arithmetic task. The experimental magnitude comparison tasks were presented in non-symbolic and symbolic formats. DD and typically developing (TD) children showed similar numerical distance and size congruity effects. However, DD children performed significantly slower in the symbolic task. These results are consistent with the access deficit hypothesis, according to which DD children's deficits are caused by difficulties accessing magnitude information from numerical symbols rather than in processing numerosities per se.

Adapting to the surface: A comparison of handwriting measures when writing on a tablet computer and on paper.

PubMed

Gerth, Sabrina; Dolk, Thomas; Klassert, Annegret; Fliesser, Michael; Fischer, Martin H; Nottbusch, Guido; Festman, Julia

2016-08-01

Our study addresses the following research questions: Are there differences between handwriting movements on paper and on a tablet computer? Can experienced writers, such as most adults, adapt their graphomotor execution during writing to a rather unfamiliar surface for instance a tablet computer? We examined the handwriting performance of adults in three tasks with different complexity: (a) graphomotor abilities, (b) visuomotor abilities and (c) handwriting. Each participant performed each task twice, once on paper and once on a tablet computer with a pen. We tested 25 participants by measuring their writing duration, in air time, number of pen lifts, writing velocity and number of inversions in velocity. The data were analyzed using linear mixed-effects modeling with repeated measures. Our results reveal differences between writing on paper and on a tablet computer which were partly task-dependent. Our findings also show that participants were able to adapt their graphomotor execution to the smoother surface of the tablet computer during the tasks. Copyright © 2016 Elsevier B.V. All rights reserved.

Environmental Stress and Human Migration in a Low-lying Developing Nation: A Comparison of Co-evolving Natural and Human Landscapes in the Physically and Culturally Diverse Context of Bangladesh

DTIC Science & Technology

2013-09-30

preclude the deposition of sediment and organic matter that normally sustains the elevation and fertility of the landscape. In May 2012 we conducted a fast...Bangladesh. How do groups self- organize to be successful in the face of changing environment, and social and economic pressures? What are the strategies and...ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Vanderbilt

Task exposures in an office environment: a comparison of methods.

PubMed

Van Eerd, Dwayne; Hogg-Johnson, Sheilah; Mazumder, Anjali; Cole, Donald; Wells, Richard; Moore, Anne

2009-10-01

Task-related factors such as frequency and duration are associated with musculoskeletal disorders in office settings. The primary objective was to compare various task recording methods as measures of exposure in an office workplace. A total of 41 workers from different jobs were recruited from a large urban newspaper (71% female, mean age 41 years SD 9.6). Questionnaire, task diaries, direct observation and video methods were used to record tasks. A common set of task codes was used across methods. Different estimates of task duration, number of tasks and task transitions arose from the different methods. Self-report methods did not consistently result in longer task duration estimates. Methodological issues could explain some of the differences in estimates seen between methods observed. It was concluded that different task recording methods result in different estimates of exposure likely due to different exposure constructs. This work addresses issues of exposure measurement in office environments. It is of relevance to ergonomists/researchers interested in how to best assess the risk of injury among office workers. The paper discusses the trade-offs between precision, accuracy and burden in the collection of computer task-based exposure measures and different underlying constructs captures in each method.

Comparing observer models and feature selection methods for a task-based statistical assessment of digital breast tomsynthesis in reconstruction space

NASA Astrophysics Data System (ADS)

Park, Subok; Zhang, George Z.; Zeng, Rongping; Myers, Kyle J.

2014-03-01

A task-based assessment of image quality1 for digital breast tomosynthesis (DBT) can be done in either the projected or reconstructed data space. As the choice of observer models and feature selection methods can vary depending on the type of task and data statistics, we previously investigated the performance of two channelized- Hotelling observer models in conjunction with 2D Laguerre-Gauss (LG) and two implementations of partial least squares (PLS) channels along with that of the Hotelling observer in binary detection tasks involving DBT projections.2, 3 The difference in these observers lies in how the spatial correlation in DBT angular projections is incorporated in the observer's strategy to perform the given task. In the current work, we extend our method to the reconstructed data space of DBT. We investigate how various model observers including the aforementioned compare for performing the binary detection of a spherical signal embedded in structured breast phantoms with the use of DBT slices reconstructed via filtered back projection. We explore how well the model observers incorporate the spatial correlation between different numbers of reconstructed DBT slices while varying the number of projections. For this, relatively small and large scan angles (24° and 96°) are used for comparison. Our results indicate that 1) given a particular scan angle, the number of projections needed to achieve the best performance for each observer is similar across all observer/channel combinations, i.e., Np = 25 for scan angle 96° and Np = 13 for scan angle 24°, and 2) given these sufficient numbers of projections, the number of slices for each observer to achieve the best performance differs depending on the channel/observer types, which is more pronounced in the narrow scan angle case.

Representation of numerosity in posterior parietal cortex

PubMed Central

Roitman, Jamie D.; Brannon, Elizabeth M.; Platt, Michael L.

2012-01-01

Humans and animals appear to share a similar representation of number as an analog magnitude on an internal, subjective scale. Neurological and neurophysiological data suggest that posterior parietal cortex (PPC) is a critical component of the circuits that form the basis of numerical abilities in humans. Patients with parietal lesions are impaired in their ability to access the deep meaning of numbers. Acalculiac patients with inferior parietal damage often have difficulty performing arithmetic (2 + 4?) or number bisection (what is between 3 and 5?) tasks, but are able to recite multiplication tables and read or write numerals. Functional imaging studies of neurologically intact humans performing subtraction, number comparison, and non-verbal magnitude comparison tasks show activity in areas within the intraparietal sulcus (IPS). Taken together, clinical cases and imaging studies support a critical role for parietal cortex in the mental manipulation of numerical quantities. Further, responses of single PPC neurons in non-human primates are sensitive to the numerosity of visual stimuli independent of low-level stimulus qualities. When monkeys are trained to make explicit judgments about the numerical value of such stimuli, PPC neurons encode their cardinal numerical value; without such training PPC neurons appear to encode numerical magnitude in an analog fashion. Here we suggest that the spatial and integrative properties of PPC neurons contribute to their critical role in numerical cognition. PMID:22666194

A Comparison of Two Methods Used for Ranking Task Exposure Levels Using Simulated Multi-Task Data

DTIC Science & Technology

1999-12-17

OF OKLAHOMA HEALTH SCIENCES CENTER GRADUATE COLLEGE A COMPARISON OF TWO METHODS USED FOR RANKING TASK EXPOSURE LEVELS USING SIMULATED MULTI-TASK...COSTANTINO Oklahoma City, Oklahoma 1999 ^ooo wx °^ A COMPARISON OF TWO METHODS USED FOR RANKING TASK EXPOSURE LEVELS USING SIMULATED MULTI-TASK DATA... METHODS AND MATERIALS 9 TV. RESULTS 14 V. DISCUSSION AND CONCLUSION 28 LIST OF REFERENCES 31 APPENDICES 33 Appendix A JJ -in Appendix B Dl IV

Comparison versus Contrast: Task Specifics Affect Category Acquisition

ERIC Educational Resources Information Center

Ankowski, Amber A.; Vlach, Haley A.; Sandhofer, Catherine M.

2013-01-01

A large literature has documented that comparison and contrast lead to better performance in a variety of tasks. However, studies of comparison and contrast present contradictory conclusions as to when and how these processes benefit learners. Across four studies, we examined how the specifics of the comparison and contrast task affect performance…

Breaking down number syntax: spared comprehension of multi-digit numbers in a patient with impaired digit-to-word conversion.

PubMed

Dotan, Dror; Friedmann, Naama; Dehaene, Stanislas

2014-10-01

Can the meaning of two-digit Arabic numbers be accessed independently of their verbal-phonological representations? To answer this question we explored the number processing of ZN, an aphasic patient with a syntactic deficit in digit-to-verbal transcoding, who could hardly read aloud two-digit numbers, but could read them as single digits ("four, two"). Neuropsychological examination showed that ZN's deficit was neither in the digit input nor in the phonological output processes, as he could copy and repeat two-digit numbers. His deficit thus lied in a central process that converts digits to abstract number words and sends this information to phonological retrieval processes. Crucially, in spite of this deficit in number transcoding, ZN's two-digit comprehension was spared in several ways: (1) he could calculate two-digit additions; (2) he showed good performance in a two-digit comparison task, and a continuous distance effect; and (3) his performance in a task of mapping numbers to positions on an unmarked number line showed a logarithmic (nonlinear) factor, indicating that he represented two-digit Arabic numbers as holistic two-digit quantities. Thus, at least these aspects of number comprehension can be performed without converting the two-digit number from digits to verbal representation.

Stimulus-reinforcement Based Decision-making and Anxiety: Impairment in Generalized Anxiety Disorder (GAD), but not in Generalized Social Phobia (GSP)

PubMed Central

DeVido, Jeffrey; Jones, Matthew; Geraci, Marilla; Hollon, Nick; Blair, R. J. R.; Pine, Daniel S.; Blair, Karina

2010-01-01

Background Generalized Social Phobia (GSP) involves the fear/avoidance of social situations while Generalized Anxiety Disorder (GAD) involves an intrusive worry about everyday life circumstances. It remains unclear whether these, highly comorbid, conditions represent distinct disorders or alternative presentations of a single underlying pathology. In this study, we examined stimulus-reinforcement based decision-making in GSP and GAD. Methods Twenty unmedicated patients with GSP, sixteen unmedicated patients with GAD and nineteen age, IQ, and gender matched healthy comparison individuals completed the Differential Reward/ Punishment Learning Task (DRPLT). In this task, the subject chooses between two objects associated with different levels of reward or punishment. Thus, response choice indexes not only reward/ punishment sensitivity but also sensitivity to reward/ punishment level according to between-object reinforcement distance. Results We found that patients with GAD committed a significantly greater number of errors compared to both the patients with GSP and the healthy comparison individuals. In contrast, the patients with GSP and the healthy comparison individuals did not differ in performance on this task. Conclusions These results link GAD with an anomalous non-affective based decision-making. Further, they are indicative that GSP and GAD are associated with distinct pathophysiologies. PMID:19102795

Differences in Arithmetic Performance between Chinese and German Children Are Accompanied by Differences in Processing of Symbolic Numerical Magnitude

PubMed Central

Lonnemann, Jan; Linkersdörfer, Janosch; Hasselhorn, Marcus; Lindberg, Sven

2016-01-01

Symbolic numerical magnitude processing skills are assumed to be fundamental to arithmetic learning. It is, however, still an open question whether better arithmetic skills are reflected in symbolic numerical magnitude processing skills. To address this issue, Chinese and German third graders were compared regarding their performance in arithmetic tasks and in a symbolic numerical magnitude comparison task. Chinese children performed better in the arithmetic tasks and were faster in deciding which one of two Arabic numbers was numerically larger. The group difference in symbolic numerical magnitude processing was fully mediated by the performance in arithmetic tasks. We assume that a higher degree of familiarity with arithmetic in Chinese compared to German children leads to a higher speed of retrieving symbolic numerical magnitude knowledge. PMID:27630606

The Transient Excitation and Oscillation Testing Technique Applied to a Captive Model.

DTIC Science & Technology

1981-06-01

8217Kall io I 9. PERFORMING ORGANIZATION NAME AND ADDRESS PROGRAM ELEMENT. PROJECT, TASK David W. Tayl.or Naval Ship Research and -OW UNIT NUMBERS...corrective tare terms (C’. 11 C35’ C 53 and C 55) used in calculating the nondimensional oscillat ion coff ticient s. Figures 7--14 contain comparisons of

Special Programs in Medical Library Education, 1957-1971: Part IV. Career Characteristics of Two Groups of Medical Librarians *†

PubMed Central

Roper, Fred W.

1974-01-01

This final report compares career characteristics of former trainees employed in medical libraries in 1971 with those of another group of professional medical librarians who did not enter medical librarianship from special training programs. Career characteristics include career advancement (position level, number of people supervised, salary level), professional utilization (tasks perforṁed), and professional activity (association memberships and offices, number of journals read, continuing education activity). The comparison of characteristics for the two groups showed many similarities. A major difference appeared in the career advancement comparison. For the former trainees, economic advancement seems less dependent on upward movement in line positions. This suggests the possibility of two career tracks available to them. PMID:4462688

Eye movements reflect and shape strategies in fraction comparison

PubMed Central

Ischebeck, Anja; Weilharter, Marina; Körner, Christof

2016-01-01

The comparison of fractions is a difficult task that can often be facilitated by separately comparing components (numerators and denominators) of the fractions—that is, by applying so-called component-based strategies. The usefulness of such strategies depends on the type of fraction pair to be compared. We investigated the temporal organization and the flexibility of strategy deployment in fraction comparison by evaluating sequences of eye movements in 20 young adults. We found that component-based strategies could account for the response times and the overall number of fixations observed for the different fraction pairs. The analysis of eye movement sequences showed that the initial eye movements in a trial were characterized by stereotypical scanning patterns indicative of an exploratory phase that served to establish the kind of fraction pair presented. Eye movements that followed this phase adapted to the particular type of fraction pair and indicated the deployment of specific comparison strategies. These results demonstrate that participants employ eye movements systematically to support strategy use in fraction comparison. Participants showed a remarkable flexibility to adapt to the most efficient strategy on a trial-by-trial basis. Our results confirm the value of eye movement measurements in the exploration of strategic adaptation in complex tasks. PMID:26039819

The role of inhibition for working memory processes: ERP evidence from a short-term storage task.

PubMed

Getzmann, Stephan; Wascher, Edmund; Schneider, Daniel

2018-05-01

Human working memory is the central unit for short-term storage of information. In addition to the selection and adequate storage of relevant information, the suppression of irrelevant stimuli from the environment seems to be of importance for working memory processes. To learn more about the interplay of information uptake and inhibition of irrelevant information, the present study used ERP measures and a short-term storage and retrieval task, in which pairs of either numbers or letters had to be compared. Random sequences of four stimuli (two numbers and two letters) were presented, with either the numbers or the letters being relevant for comparison. The analysis of ERPs to each of the four stimuli indicated more pronounced P2 and P3b amplitudes for relevant than irrelevant stimuli. In contrast, the N2 (reflecting inhibitory control) was only elicited by irrelevant stimuli. Moreover, the N2 amplitude of the second irrelevant stimulus was associated with behavioral performance, indicating the importance of inhibition of task-irrelevant stimuli for working memory processes. In sum, the findings demonstrate the role of cognitive control mechanisms for protecting relevant contents in working memory against irrelevant information. © 2017 Society for Psychophysiological Research.

Detecting gait abnormalities after concussion or mild traumatic brain injury: A systematic review of single-task, dual-task, and complex gait.

PubMed

Fino, Peter C; Parrington, Lucy; Pitt, Will; Martini, Douglas N; Chesnutt, James C; Chou, Li-Shan; King, Laurie A

2018-05-01

While a growing number of studies have investigated the effects of concussion or mild traumatic brain injury (mTBI) on gait, many studies use different experimental paradigms and outcome measures. The path for translating experimental studies for objective clinical assessments of gait is unclear. This review asked 2 questions: 1) is gait abnormal after concussion/mTBI, and 2) what gait paradigms (single-task, dual-task, complex gait) detect abnormalities after concussion. Data sources included MEDLINE/PubMed, Scopus, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) accessed on March 14, 2017. Original research articles reporting gait outcomes in people with concussion or mTBI were included. Studies of moderate, severe, or unspecified TBI, and studies without a comparator were excluded. After screening 233 articles, 38 studies were included and assigned to one or more sections based on the protocol and reported outcomes. Twenty-six articles reported single-task simple gait outcomes, 24 reported dual-task simple gait outcomes, 21 reported single-task complex gait outcomes, and 10 reported dual-task complex gait outcomes. Overall, this review provides evidence for two conclusions: 1) gait is abnormal acutely after concussion/mTBI but generally resolves over time; and 2) the inconsistency of findings, small sample sizes, and small number of studies examining homogenous measures at the same time-period post-concussion highlight the need for replication across independent populations and investigators. Future research should concentrate on dual-task and complex gait tasks, as they showed promise for detecting abnormal locomotor function outside of the acute timeframe. Additionally, studies should provide detailed demographic and clinical characteristics to enable more refined comparisons across studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Performance-informed EEG analysis reveals mixed evidence for EEG signatures unique to the processing of time.

PubMed

Schlichting, Nadine; de Jong, Ritske; van Rijn, Hedderik

2018-06-20

Certain EEG components (e.g., the contingent negative variation, CNV, or beta oscillations) have been linked to the perception of temporal magnitudes specifically. However, it is as of yet unclear whether these EEG components are really unique to time perception or reflect the perception of magnitudes in general. In the current study we recorded EEG while participants had to make judgments about duration (time condition) or numerosity (number condition) in a comparison task. This design allowed us to directly compare EEG signals between the processing of time and number. Stimuli consisted of a series of blue dots appearing and disappearing dynamically on a black screen. Each stimulus was characterized by its duration and the total number of dots that it consisted of. Because it is known that tasks like these elicit perceptual interference effects that we used a maximum-likelihood estimation (MLE) procedure to determine, for each participant and dimension separately, to what extent time and numerosity information were taken into account when making a judgement in an extensive post hoc analysis. This approach enabled us to capture individual differences in behavioral performance and, based on the MLE estimates, to select a subset of participants who suppressed task-irrelevant information. Even for this subset of participants, who showed no or only small interference effects and thus were thought to truly process temporal information in the time condition and numerosity information in the number condition, we found CNV patterns in the time-domain EEG signals for both tasks that was more pronounced in the time-task. We found no substantial evidence for differences between the processing of temporal and numerical information in the time-frequency domain.

Multiple numeric competencies: When a number is not just a number.

PubMed

Peters, Ellen; Bjalkebring, Par

2015-05-01

A growing body of evidence demonstrates the practical and theoretical importance of numeracy in evaluations and choices involving numeric information, an importance that goes beyond simple accuracy in performing mathematical computations. Numeric competency, however, may be multiply determined, but little research has examined potentially separable influences in evaluations and choice. In the present article, we describe 3 numeric competencies and begin to disentangle their effects. Participants (N = 111) completed a series of tasks in 4 1-hr sessions. We first examined relations between objective numeracy, subjective numeracy, and symbolic-number mapping abilities (thought to tap into internal representations of numeric magnitude and the mapping of symbolic numbers onto those representations) using a structural equation model. We then explored their dissociations in numeric and nonnumeric tasks. Higher vs. lower scores in objective numeracy were associated with explicit number operations, including number comparisons and calculations. Those with more vs. less exact mapping had better numeric memory (but not nonnumeric) and produced valuations that were closer to (but did not equal) a risky gamble's expected value, indicating a link with superior number intuitions. Finally, individuals lower vs. higher in subjective numeracy had more negative emotional reactions to numbers and were less motivated and/or confident in numeric tasks. It was less clear whether subjective numeracy might also relate to more general motivations and metacognitions involving nonnumeric information. We conclude that numeric competencies should be used in a more targeted fashion to understand their multiple mechanisms in people's evaluations, choices, and life outcomes. (c) 2015 APA, all rights reserved).

An Improved Measure of Cognitive Salience in Free Listing Tasks: A Marshallese Example

ERIC Educational Resources Information Center

Robbins, Michael C.; Nolan, Justin M.; Chen, Diana

2017-01-01

A new free-list measure of cognitive salience, B', is presented, which includes both list position and list frequency. It surpasses other extant measures by being normed to vary between a maximum of 1 and a minimum of 0, thereby making it useful for comparisons irrespective of list length or number of respondents. An illustration of its…

Project LASER: Learning about science, engineering, and research

NASA Technical Reports Server (NTRS)

1990-01-01

The number of American students entering science and engineering careers and their ranking in comparison with other countries is on the decline. This decline has alarmed Congress which, in 1987, established a Task Force on Women, Minorities, and the Handicapped in Science and Technology to define the problem and find solutions. If left unchanged, the task force has warned that the prospects for maintaining an advanced industrial society will diminish. NASA is supportive of the six goals outlined by the task force, which are paraphrase herein, and is carefully assessing its education programs to identify those offering the greatest potential for achieving the task force objectives with a reasonable range of resources. A major initiative is under way on behalf of NASA at its Marshall Space Flight Center, where highly effective features of several NASA education programs along with innovations are being integrated into a comprehensive pilot program. This program, dubbed Project LASER, is discussed.

Behavioral Economics of Cigarette Purchase Tasks: Within-Subject Comparison of Real, Potentially Real, and Hypothetical Cigarettes

PubMed Central

Wilson, A. George; Franck, Christopher T.; Koffarnus, Mikhail N.

2016-01-01

Abstract Introduction: Hypothetical rewards are commonly used in studies of laboratory-based tobacco demand. However, behavioral economic demand procedures require confirmation that the behavior elicited from real and hypothetical reward types are equivalent, and that results attained from these procedures are comparable to other accepted tasks, such as the hypothetical purchase task. Methods: Nineteen smokers were asked to purchase 1 week’s worth of cigarettes that they would consume over the following week either at one price that incrementally increased across four weekly sessions (“real” sessions) or four prices in a single session (“potentially real” session), one of which was randomly chosen to be actualized. At each session, participants also completed a hypothetical cigarette purchase task. After each week, participants reported the number of cigarettes they actually smoked. Results: Demand was found to be equivalent under both the real and potentially real reward conditions but statistically different from the demand captured in the hypothetical purchase task. However, the amounts purchased at specific prices in the hypothetical purchase task were significantly correlated with the amount purchased at comparable prices in the other two tasks (except for the highest price examined in both tasks of $1.00 per cigarette). Number of cigarettes consumed that were obtained outside of the study was correlated with study cigarette price. Conclusions: Combined, these results suggest that purchasing behavior during potentially real sessions (1) was not functionally different from real sessions, (2) imposes fewer costs to the experimenter, and (3) has high levels of both internal and external validity. PMID:26187389

Validation of a novel attentional bias modification task: the future may be in the cards.

PubMed

Notebaert, Lies; Clarke, Patrick J F; Grafton, Ben; MacLeod, Colin

2015-02-01

Attentional bias modification (ABM) is a promising therapeutic tool aimed at changing patterns of attentional selectivity associated with heightened anxiety. A number of studies have successfully implemented ABM using the modified dot-probe task. However others have not achieved the attentional change required to achieve emotional benefits, highlighting the need for new ABM methods. The current study compared the effectiveness of a newly developed ABM task against the traditional dot-probe ABM task. The new person-identity-matching (PIM) task presented participants with virtual cards, each depicting a happy and angry person. The task encourages selective attention toward or away from threat by requiring participants to make matching judgements between two cards, based either on the identities of the happy faces, or of the angry faces. Change in attentional bias achieved by both ABM tasks was measured by a dot-probe assessment task. Their impact on emotional vulnerability was assessed by measuring negative emotional reactions to a video stressor. The PIM task succeeded in modifying attentional bias, and exerting an impact on emotional reactivity, whereas this was not the case for the dot-probe task. These results are considered in relation to the potential clinical utility of the current task in comparison to traditional ABM methodologies. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Submodularity Framework for Data Subset Selection

DTIC Science & Technology

2013-09-01

37 7 List of Language Modeling Corpora in thet Arabic -to-English NIST Task ............. 37 8...Task ( Arabic -to-English) ................. 39 10 Baseline BLEU (%) PER Scores on Transtac Task (English-to- Arabic ) ................. 39 11...Comparison of BLEU (%) PER Scores on Transtac Task ( Arabic -to-English) ....... 39 12 Comparison of BLEU (%) PER Scores on Transtac Task (English-to- Arabic

Self-referenced memory, social cognition, and symptom presentation in autism.

PubMed

Henderson, Heather A; Zahka, Nicole E; Kojkowski, Nicole M; Inge, Anne P; Schwartz, Caley B; Hileman, Camilla M; Coman, Drew C; Mundy, Peter C

2009-07-01

We examined performance on a self-referenced memory (SRM) task for higher-functioning children with autism (HFA) and a matched comparison group. SRM performance was examined in relation to symptom severity and social cognitive tests of mentalizing. Sixty-two children (31 HFA, 31 comparison; 8-16 years) completed a SRM task in which they read a list of words and decided whether the word described something about them, something about Harry Potter, or contained a certain number of letters. They then identified words that were familiar from a longer list. Dependent measures were memory performance (d') in each of the three encoding conditions as well as a self-memory bias score (d' self-d' other). Children completed The Strange Stories Task and The Children's Eyes Test as measures of social cognition. Parents completed the SCQ and ASSQ as measures of symptom severity. Children in the comparison sample showed the standard SRM effect in which they recognized significantly more self-referenced words relative to words in the other-referenced and letter conditions. In contrast, HFA children showed comparable rates of recognition for self- and other-referenced words. For all children, SRM performance improved with age and enhanced SRM performance was related to lower levels of social problems. These associations were not accounted for by performance on the mentalizing tasks. Children with HFA did not show the standard enhanced processing of self- vs. other-relevant information. Individual differences in the tendency to preferentially process self-relevant information may be associated with social cognitive processes that serve to modify the expression of social symptoms in children with autism.

The contributions of numerical acuity and non-numerical stimulus features to the development of the number sense and symbolic math achievement.

PubMed

Starr, Ariel; DeWind, Nicholas K; Brannon, Elizabeth M

2017-11-01

Numerical acuity, frequently measured by a Weber fraction derived from nonsymbolic numerical comparison judgments, has been shown to be predictive of mathematical ability. However, recent findings suggest that stimulus controls in these tasks are often insufficiently implemented, and the proposal has been made that alternative visual features or inhibitory control capacities may actually explain this relation. Here, we use a novel mathematical algorithm to parse the relative influence of numerosity from other visual features in nonsymbolic numerical discrimination and to examine the strength of the relations between each of these variables, including inhibitory control, and mathematical ability. We examined these questions developmentally by testing 4-year-old children, 6-year-old children, and adults with a nonsymbolic numerical comparison task, a symbolic math assessment, and a test of inhibitory control. We found that the influence of non-numerical features decreased significantly over development but that numerosity was a primary determinate of decision making at all ages. In addition, numerical acuity was a stronger predictor of math achievement than either non-numerical bias or inhibitory control in children. These results suggest that the ability to selectively attend to number contributes to the maturation of the number sense and that numerical acuity, independent of inhibitory control, contributes to math achievement in early childhood. Copyright © 2017 Elsevier B.V. All rights reserved.

Spatial coding of object typical size: evidence for a SNARC-like effect.

PubMed

Sellaro, Roberta; Treccani, Barbara; Job, Remo; Cubelli, Roberto

2015-11-01

The present study aimed to assess whether the representation of the typical size of objects can interact with response position codes in two-choice bimanual tasks, and give rise to a SNARC-like effect (faster responses when the representation of the typical size of the object to which the target stimulus refers corresponds to response side). Participants performed either a magnitude comparison task (in which they were required to judge whether the target was smaller or larger than a reference stimulus; Experiment 1) or a semantic decision task (in which they had to classify the target as belonging to either the category of living or non-living entities; Experiment 2). Target stimuli were pictures or written words referring to either typically large and small animals or inanimate objects. In both tasks, participants responded by pressing a left- or right-side button. Results showed that, regardless of the to-be-performed task (magnitude comparison or semantic decision) and stimulus format (picture or word), left responses were faster when the target represented typically small-sized entities, whereas right responses were faster for typically large-sized entities. These results provide evidence that the information about the typical size of objects is activated even if it is not requested by the task, and are consistent with the idea that objects' typical size is automatically spatially coded, as has been proposed to occur for number magnitudes. In this representation, small objects would be on the left and large objects would be on the right. Alternative interpretations of these results are also discussed.

A university teaching simulation facility

NASA Technical Reports Server (NTRS)

Stark, Lawrence; Kim, Won-Soo; Tendick, Frank; Tyler, Mitchell; Hannaford, Blake; Barakat, Wissam; Bergengruen, Olaf; Braddi, Louis; Eisenberg, Joseph; Ellis, Stephen

1987-01-01

An experimental telerobotics (TR) simulation is described suitable for studying human operator (HO) performance. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. A number of control modes could be compared in this TR simulation, including displacement, rate, and acceleratory control using position and force joysticks. A homeomorphic controller turned out to be no better than joysticks; the adaptive properties of the HO can apparently permit quite good control over a variety of controller configurations and control modes. Training by optimal control example seemed helpful in preliminary experiments.

Observed behaviours of pre-term children in a social play situation with classroom peers.

PubMed

Nadeau, Line; Tessier, Réjean; Descôteaux, Amélie

2009-08-01

A number of studies have reported social adjustment problems in pre-term children. To observe the pre-term's behaviour in an experimental situation and correlate these observed behaviours with the children's peer-rated social behaviours (withdrawal, aggression and sociability/leadership). Of 56 pre-term children, 24 were classified as the sick pre-term (SPT) group and 32 children as the healthy pre-term (HPT) group. The comparison group comprised 56 healthy full-terms. The experimental situation used a game called Rush Hour, a labyrinth-type board game. The play situation was videotaped and behaviours (number of consecutive moves) were coded in real time. At 12 years of age, the sick pre-term (SPT) group exhibited fewer consecutive moves during the game than the other two groups, especially when the task became more complex (involving four consecutives moves). Moreover, the Complex Task Index was correlated with the social withdrawal score rated by peers. The at-birth sick pre-term gradually became less involved in a complex decision-making task and this was understood as a lesser ability to make a decision in a complex setting.

Effects of symbol type and numerical distance on the human event-related potential.

PubMed

Jiang, Ting; Qiao, Sibing; Li, Jin; Cao, Zhongyu; Gao, Xuefei; Song, Yan; Xue, Gui; Dong, Qi; Chen, Chuansheng

2010-01-01

This study investigated the influence of the symbol type and numerical distance of numbers on the amplitudes and peak latencies of event-related potentials (ERPs). Our aim was to (1) determine the point in time of magnitude information access in visual number processing; and (2) identify at what stage the advantage of Arabic digits over Chinese verbal numbers occur. ERPs were recorded from 64 scalp sites while subjects (n=26) performed a classification task. Results showed that larger ERP amplitudes were elicited by numbers with distance-close condition in comparison to distance-far condition in the VPP component over centro-frontal sites. Furthermore, the VPP latency varied as a function of the symbol type, but the N170 did not. Such results demonstrate that magnitude information access takes place as early as 150 ms after onset of visual number stimuli and the advantage of Arabic digits over verbal numbers should be localized to the VPP component. We establish the VPP component as a critical ERP component to report in studies of numerical cognition and our results call into question the N170/VPP association hypothesis and the serial-stage model of visual number comparison processing.

Eye-movement patterns during nonsymbolic and symbolic numerical magnitude comparison and their relation to math calculation skills.

PubMed

Price, Gavin R; Wilkey, Eric D; Yeo, Darren J

2017-05-01

A growing body of research suggests that the processing of nonsymbolic (e.g. sets of dots) and symbolic (e.g. Arabic digits) numerical magnitudes serves as a foundation for the development of math competence. Performance on magnitude comparison tasks is thought to reflect the precision of a shared cognitive representation, as evidence by the presence of a numerical ratio effect for both formats. However, little is known regarding how visuo-perceptual processes are related to the numerical ratio effect, whether they are shared across numerical formats, and whether they relate to math competence independently of performance outcomes. The present study investigates these questions in a sample of typically developing adults. Our results reveal a pattern of associations between eye-movement measures, but not their ratio effects, across formats. This suggests that ratio-specific visuo-perceptual processing during magnitude processing is different across nonsymbolic and symbolic formats. Furthermore, eye movements are related to math performance only during symbolic comparison, supporting a growing body of literature suggesting symbolic number processing is more strongly related to math outcomes than nonsymbolic magnitude processing. Finally, eye-movement patterns, specifically fixation dwell time, continue to be negatively related to math performance after controlling for task performance (i.e. error rate and reaction time) and domain general cognitive abilities (IQ), suggesting that fluent visual processing of Arabic digits plays a unique and important role in linking symbolic number processing to formal math abilities. Copyright © 2017 Elsevier B.V. All rights reserved.

Methods for the analysis of ordinal response data in medical image quality assessment.

PubMed

Keeble, Claire; Baxter, Paul D; Gislason-Lee, Amber J; Treadgold, Laura A; Davies, Andrew G

2016-07-01

The assessment of image quality in medical imaging often requires observers to rate images for some metric or detectability task. These subjective results are used in optimization, radiation dose reduction or system comparison studies and may be compared to objective measures from a computer vision algorithm performing the same task. One popular scoring approach is to use a Likert scale, then assign consecutive numbers to the categories. The mean of these response values is then taken and used for comparison with the objective or second subjective response. Agreement is often assessed using correlation coefficients. We highlight a number of weaknesses in this common approach, including inappropriate analyses of ordinal data and the inability to properly account for correlations caused by repeated images or observers. We suggest alternative data collection and analysis techniques such as amendments to the scale and multilevel proportional odds models. We detail the suitability of each approach depending upon the data structure and demonstrate each method using a medical imaging example. Whilst others have raised some of these issues, we evaluated the entire study from data collection to analysis, suggested sources for software and further reading, and provided a checklist plus flowchart for use with any ordinal data. We hope that raised awareness of the limitations of the current approaches will encourage greater method consideration and the utilization of a more appropriate analysis. More accurate comparisons between measures in medical imaging will lead to a more robust contribution to the imaging literature and ultimately improved patient care.

Visual Form Perception Can Be a Cognitive Correlate of Lower Level Math Categories for Teenagers.

PubMed

Cui, Jiaxin; Zhang, Yiyun; Cheng, Dazhi; Li, Dawei; Zhou, Xinlin

2017-01-01

Numerous studies have assessed the cognitive correlates of performance in mathematics, but little research has been conducted to systematically examine the relations between visual perception as the starting point of visuospatial processing and typical mathematical performance. In the current study, we recruited 223 seventh graders to perform a visual form perception task (figure matching), numerosity comparison, digit comparison, exact computation, approximate computation, and curriculum-based mathematical achievement tests. Results showed that, after controlling for gender, age, and five general cognitive processes (choice reaction time, visual tracing, mental rotation, spatial working memory, and non-verbal matrices reasoning), visual form perception had unique contributions to numerosity comparison, digit comparison, and exact computation, but had no significant relation with approximate computation or curriculum-based mathematical achievement. These results suggest that visual form perception is an important independent cognitive correlate of lower level math categories, including the approximate number system, digit comparison, and exact computation.

Context influences decision-making in boys with attention-deficit/hyperactivity disorder: A comparison of traditional and novel choice-impulsivity paradigms.

PubMed

Patros, Connor H G; Alderson, R Matt; Lea, Sarah E; Tarle, Stephanie J

2017-02-01

Attention-deficit/hyperactivity disorder (ADHD) is characterized by an impaired ability to maintain attention and/or hyperactivity/impulsivity. Impulsivity is frequently defined as the preference for small, immediate rewards over larger, delayed rewards, and has been associated with a variety of negative outcomes such as risky behavior and academic difficulty. Extant studies have uniformly utilized the traditional paradigm of presenting two response choices, which limits the generalization of findings to scenarios in which children/adolescents are faced with dichotomous decisions. The current study is the first to examine the effect of manipulating the number of available response options on impulsive decision-making in boys with and without ADHD. A total of 39 boys (ADHD = 16, typically developing [TD] = 23) aged 8-12 years completed a traditional two-choice impulsivity task and a novel five-choice impulsivity task to examine the effect of manipulating the number of choice responses (two vs five) on impulsive decision-making. A five-choice task was utilized as it presents a more continuous array of choice options when compared to the typical two-choice task, and is comparable given its methodological similarity to the two-choice task. Results suggested that boys with ADHD were significantly more impulsive than TD boys during the two-choice task, but not during the five-choice task. Collectively, these findings suggest that ADHD-related impulsivity is not ubiquitous, but rather dependent on variation in demands and/or context. Further, these findings highlight the importance of examining ADHD-related decision-making within the context of alternative paradigms, as the exclusive utilization of two-choice tasks may promote inaccurate conceptualizations of the disorder.

Promoting broad and stable improvements in low-income children's numerical knowledge through playing number board games.

PubMed

Ramani, Geetha B; Siegler, Robert S

2008-01-01

Theoretical analyses of the development of numerical representations suggest that playing linear number board games should enhance young children's numerical knowledge. Consistent with this prediction, playing such a game for roughly 1 hr increased low-income preschoolers' (mean age = 5.4 years) proficiency on 4 diverse numerical tasks: numerical magnitude comparison, number line estimation, counting, and numeral identification. The gains remained 9 weeks later. Classmates who played an identical game, except for the squares varying in color rather than number, did not improve on any measure. Also as predicted, home experience playing number board games correlated positively with numerical knowledge. Thus, playing number board games with children from low-income backgrounds may increase their numerical knowledge at the outset of school.

Perceiving numbers does not cause automatic shifts of spatial attention.

PubMed

Fattorini, Enrico; Pinto, Mario; Rotondaro, Francesca; Doricchi, Fabrizio

2015-12-01

It is frequently assumed that the brain codes number magnitudes according to an inherent left-to-right spatial organization. In support of this hypothesis it has been reported that in humans, perceiving small numbers induces automatic shifts of attention toward the left side of space whereas perceiving large numbers automatically shifts attention to the right side of space (i.e., Attentional SNARC: Att-SNARC; Fischer, Castel, Dodd, & Pratt, 2003). Nonetheless, the Att-SNARC has been often not replicated and its reliability never tested. To ascertain whether the mere perception of numbers causes shifts of spatial attention or whether number-space interaction takes place at a different stage of cognitive processing, we re-assessed the consistency and reliability of the Att-SNARC and investigated its role in the production of SNARC effects in Parity Judgement (PJ) and Magnitude Comparison (MC) tasks. In a first study in 60 participants, we found no Att-SNARC, despite finding strong PJ- and MC-SNARC effects. No correlation was present between the Att-SNARC and the SNARC. Split-half tests showed no reliability of the Att-SNARC and high reliability of the PJ- and MC-SNARC. In a second study, we re-assessed the Att-SNARC and tested its direct influence on a MC-SNARC task with laterally presented targets. No Att-SNARC and no influence of the Att-SNARC on the MC-SNARC were found. Also in this case, the SNARC was reliable whereas the Att-SNARC task was not. Finally, in a third study we observed a significant Att-SNARC when participants were asked to recall the position occupied on a ruler by the numbers presented in each trial: however the Att-SNARC task was not reliable. These results show that perceiving numbers does not cause automatic shifts of spatial attention and that whenever present, these shifts do not modulate the SNARC. The same results suggest that numbers have no inherent mental left-to-right organization and that, whenever present, this organization can have both response-related and strategically driven memory-related origins. Nonetheless, response-related factors generate more reliable and stable spatial representations of numbers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Relation between Approximate Number System Acuity and Mathematical Achievement: The Influence of Fluency

PubMed Central

Wang, Li; Sun, Yuhua; Zhou, Xinlin

2016-01-01

Previous studies have observed inconsistent relations between the acuity of the Approximate Number System (ANS) and mathematical achievement. In this paper, we hypothesize that the relation between ANS acuity and mathematical achievement is influenced by fluency; that is, the mathematical achievement test covering a greater expanse of mathematical fluency may better reflect the relation between ANS acuity and mathematics skills. We explored three types of mathematical achievement tests utilized in this study: Subtraction, graded, and semester-final examination. The subtraction test was designed to measure the mathematical fluency. The graded test was more fluency-based than the semester-final examination, but both involved the same mathematical knowledge from the class curriculum. A total of 219 fifth graders from primary schools were asked to perform all three tests, then given a numerosity comparison task, a visual form perception task (figure matching), and a series of other tasks to assess general cognitive processes (mental rotation, non-verbal matrix reasoning, and choice reaction time). The findings were consistent with our expectations. The relation between ANS acuity and mathematical achievement was particularly clearly reflected in the participants’ performance on the visual form perception task, which supports the domain-general explanations for the underlying mechanisms of the relation between ANS acuity and math achievement. PMID:28066291

Time manages interference in visual short-term memory.

PubMed

Smith, Amy V; McKeown, Denis; Bunce, David

2017-09-01

Emerging evidence suggests that age-related declines in memory may reflect a failure in pattern separation, a process that is believed to reduce the encoding overlap between similar stimulus representations during memory encoding. Indeed, behavioural pattern separation may be indexed by a visual continuous recognition task in which items are presented in sequence and observers report for each whether it is novel, previously viewed (old), or whether it shares features with a previously viewed item (similar). In comparison to young adults, older adults show a decreased pattern separation when the number of items between "old" and "similar" items is increased. Yet the mechanisms of forgetting underpinning this type of recognition task are yet to be explored in a cognitively homogenous group, with careful control over the parameters of the task, including elapsing time (a critical variable in models of forgetting). By extending the inter-item intervals, number of intervening items and overall decay interval, we observed in a young adult sample (N = 35, M age  = 19.56 years) that the critical factor governing performance was inter-item interval. We argue that tasks using behavioural continuous recognition to index pattern separation in immediate memory will benefit from generous inter-item spacing, offering protection from inter-item interference.

Genetics and mathematics: evidence from Prader-Willi syndrome.

PubMed

Semenza, Carlo; Pignatti, Riccardo; Bertella, Laura; Ceriani, Francesca; Mori, Ileana; Molinari, Enrico; Giardino, Daniela; Malvestiti, Francesca; Grugni, Graziano

2008-01-15

Mathematical abilities were tested in people with Prader-Willi syndrome (PWS), using a series of basic mathematical tasks for which normative data are available. The difference between the deletion and the disomy variants of this condition was explored. While a wide phenotypic variation was found, some basic findings emerge clearly. As expected from previous literature, deletion and disomy participants were found to differ in their degree of impairment, with disomy being overall the most spared condition. However, the tasks selectively spared in the disomy condition are not necessarily the easiest ones and those that discriminate less the PWS group from controls. It rather seems that disomy patients are spared, with respect to deletion, in tasks entailing transcoding and comparison of numbers in the Arabic code. Overall a particular difficulty was detected in reliably performing parity judgments. This task has been shown to be very frequently spared after a brain injury, even in severe aphasic conditions. The most interesting result is the sparing in analog number scale, whereby PWS seem, overall, to outperform controls. This finding may help in understanding previously reported, surprising results about cognitive skills in PWS. Elevated performances in PWS may result from life-long hyper-reliance on one visuo-spatial system in presence of underdevelopment of the other.

Self-Referenced Memory, Social Cognition, and Symptom Presentation in Autism

PubMed Central

Henderson, Heather A.; Zahka, Nicole E.; Kojkowski, Nicole M.; Inge, Anne P.; Schwartz, Caley B.; Hileman, Camilla M.; Coman, Drew C.; Mundy, Peter C.

2009-01-01

Background We examined performance on a self-referenced memory (SRM) task for higher functioning children with autism (HFA) and a matched comparison group. SRM performance was examined in relation to symptom severity and social cognitive tests of mentalizing. Method Sixty-two children (31 HFA, 31 comparison; 8–16 years) completed a SRM task in which they read a list of words and decided whether the word described something about them, something about Harry Potter, or contained a certain number of letters. They then identified words that were familiar from a longer list. Dependent measures were memory performance (d′) in each of the three encoding conditions as well as a self-memory bias score (d′ self-d′ other). Children completed The Strange Stories Task and The Children’s Eyes Test as measures of social cognition. Parents completed the SCQ and ASSQ as measures of symptom severity. Results Children in the comparison sample showed the standard SRM effect in which they recognized significantly more self-referenced words relative to words in the other-referenced and letter conditions. In contrast, HFA children showed comparable rates of recognition for self- and other-referenced words. For all children, SRM performance improved with age and enhanced SRM performance was related to lower levels of social problems. These associations were not accounted for by performance on the mentalizing tasks. Conclusions Children with HFA did not show the standard enhanced processing of self- vs. other-relevant information. Individual differences in the tendency to preferentially process self-relevant information may be associated with social cognitive processes that serve to modify the expression of social symptoms in children with autism. PMID:19298471

Numerical bias in bounded and unbounded number line tasks.

PubMed

Cohen, Dale J; Blanc-Goldhammer, Daryn

2011-04-01

The number line task is often used to assess children's and adults' underlying representations of integers. Traditional bounded number line tasks, however, have limitations that can lead to misinterpretation. Here we present a new task, an unbounded number line task, that overcomes these limitations. In Experiment 1, we show that adults use a biased proportion estimation strategy to complete the traditional bounded number line task. In Experiment 2, we show that adults use a dead-reckoning integer estimation strategy in our unbounded number line task. Participants revealed a positively accelerating numerical bias in both tasks, but showed scalar variance only in the unbounded number line task. We conclude that the unbounded number line task is a more pure measure of integer representation than the bounded number line task, and using these results, we present a preliminary description of adults' underlying representation of integers.

A Comparison of the Ship System Acquisition Process of the Greek Navy and US Navy.

DTIC Science & Technology

1984-12-01

ADDRESS 10. PROGRAM ELEMENT, PROJECT, TASK AREA & WORK UNIT NUMBERS Naval Postgraduate School Monterey, California 93943 II. CONTROLLING OFFICE NAME AND...Approved by: ------ so -- -- -= B T= ag -- - - Department of Administrative Sciences Dean of Information and Poliy Sciences 3...for their attentive assistance in all phases of this work . Furthermore, I would like tc express my sincere content- ment to: o My wife Katerina who

Structural Validity of the Movement ABC-2 Test: Factor Structure Comparisons across Three Age Groups

ERIC Educational Resources Information Center

Schulz, Joerg; Henderson, Sheila E.; Sugden, David A.; Barnett, Anna L.

2011-01-01

Background: The Movement ABC test is one of the most widely used assessments in the field of Developmental Coordination Disorder (DCD). Improvements to the 2nd edition of the test (M-ABC-2) include an extension of the age range and reduction in the number of age bands as well as revision of tasks. The total test score provides a measure of motor…

Comparative Racial Analysis of Enlisted Advancement Exams: Item- Difficulty.

DTIC Science & Technology

1975-07-01

11cm-ana lysis Promotion Racial comparison Equal opportunity 1 20. ABSTRACT (Continue on reveree aide 11 neceeemry mnd Identity by block...improving equal oppor- tunity in career growth for minority groups. The study of exam item- difficulty levels is the first of a series of technical reports...under Exploratory Development Task Area PF55.521.032 (Contemporary Social Issues). J. J. CLARKIN Commanding Officer SUMMARY Purpose A number of

A Constraint Generation Approach to Learning Stable Linear Dynamical Systems

DTIC Science & Technology

2008-01-01

task of learning dynamic textures from image sequences as well as to modeling biosurveillance drug-sales data. The constraint generation approach...previous methods in our experiments. One application of LDSs in computer vision is learning dynamic textures from video data [8]. An advantage of...over-the-counter (OTC) drug sales for biosurveillance , and sunspot numbers from the UCR archive [9]. Comparison to the best alternative methods [7, 10

Canagliflozin prevents scopolamine-induced memory impairment in rats: Comparison with galantamine hydrobromide action.

PubMed

Arafa, Nadia M S; Ali, Elham H A; Hassan, Mohamed Kamel

2017-11-01

Canagliflozin (CAN) is a sodium-glucose co-transporter 2 (SGLT2) inhibitor indicated to improve glycemic control in adults with type 2 diabetes mellitus. There is a little information about its effect on the cholinergic system that proposed mechanism for memory improvement occurring by SGLT2 drugs. This study aimed to estimate the effect of CAN as compared to galantamine (GAL) treatments for two weeks on scopolamine hydrobromide (SCO)-induced memory dysfunction in experimental rats. Animals divided into six groups; control (CON), CAN, GAL, SCO, SCO + CAN and SCO + GAL. Results indicated significant decrease in body weights of the CAN groups as compared to control values. Moreover, in the SCO + CAN and SCO + GAL the number of arm entry and number of correct alternation in Y maze task increased and showed improvement in the water maze task, acetylcholinesterase (AChE) activities decreased significantly, while monoamines levels significantly increased compared with the SCO group values. Results also recorded acetylcholine M1 receptor (M1 mAChR) in SCO + CAN or SCO + GAL groups in comparison with the SCO group. The study suggested that canagliflozin might improve memory dysfunction induced by scopolamine hydrobromide via cholinergic and monoamines system. Copyright © 2017 Elsevier B.V. All rights reserved.

Cognitive arithmetic and problem solving: a comparison of children with specific and general mathematics difficulties.

PubMed

Jordan, N C; Montani, T O

1997-01-01

This study examined problem-solving and number-fact skills in two subgroups of third-grade children with mathematics difficulties (MD): MD-specific (n = 12) and MD-general (n = 12). The MD-specific group had difficulties in mathematics but not in reading, and the MD-general group had difficulties in reading as well as in mathematics. A comparison group of nonimpaired children (n = 24) also was included. The findings showed that on both story and number-fact problems, the MD-specific group performed worse than the nonimpaired group in timed conditions but not in untimed conditions. The MD-general group, on the other hand, performed worse than the nonimpaired group, regardless of whether tasks were timed or not. An analysis of children's strategies in untimed conditions showed that both the MD-specific and the MD-general groups relied more on backup strategies than the nonimpaired group. However, children in the MD-specific group executed backup strategies more skillfully than children in the MD-general group, allowing them to achieve parity with children in the nonimpaired group when tasks were not timed. The findings suggest that children with specific MD have circumscribed deficits associated with fact retrieval, whereas children with general MD have more basic delays associated with problem conceptualization and execution of calculation procedures.

Comparison of software packages for detecting differential expression in RNA-seq studies

PubMed Central

Seyednasrollah, Fatemeh; Laiho, Asta

2015-01-01

RNA-sequencing (RNA-seq) has rapidly become a popular tool to characterize transcriptomes. A fundamental research problem in many RNA-seq studies is the identification of reliable molecular markers that show differential expression between distinct sample groups. Together with the growing popularity of RNA-seq, a number of data analysis methods and pipelines have already been developed for this task. Currently, however, there is no clear consensus about the best practices yet, which makes the choice of an appropriate method a daunting task especially for a basic user without a strong statistical or computational background. To assist the choice, we perform here a systematic comparison of eight widely used software packages and pipelines for detecting differential expression between sample groups in a practical research setting and provide general guidelines for choosing a robust pipeline. In general, our results demonstrate how the data analysis tool utilized can markedly affect the outcome of the data analysis, highlighting the importance of this choice. PMID:24300110

Comparison of software packages for detecting differential expression in RNA-seq studies.

PubMed

Seyednasrollah, Fatemeh; Laiho, Asta; Elo, Laura L

2015-01-01

RNA-sequencing (RNA-seq) has rapidly become a popular tool to characterize transcriptomes. A fundamental research problem in many RNA-seq studies is the identification of reliable molecular markers that show differential expression between distinct sample groups. Together with the growing popularity of RNA-seq, a number of data analysis methods and pipelines have already been developed for this task. Currently, however, there is no clear consensus about the best practices yet, which makes the choice of an appropriate method a daunting task especially for a basic user without a strong statistical or computational background. To assist the choice, we perform here a systematic comparison of eight widely used software packages and pipelines for detecting differential expression between sample groups in a practical research setting and provide general guidelines for choosing a robust pipeline. In general, our results demonstrate how the data analysis tool utilized can markedly affect the outcome of the data analysis, highlighting the importance of this choice. © The Author 2013. Published by Oxford University Press.

Electrophysiological dynamic brain connectivity during symbolic magnitude comparison in children with different mathematics achievement levels.

PubMed

Gómez-Velázquez, Fabiola R; Vélez-Pérez, Hugo; Espinoza-Valdez, Aurora; Romo-Vazquez, Rebeca; Salido-Ruiz, Ricardo A; Ruiz-Stovel, Vanessa; Gallardo-Moreno, Geisa B; González-Garrido, Andrés A; Berumen, Gustavo

2017-02-08

Children with mathematical difficulties usually have an impaired ability to process symbolic representations. Functional MRI methods have suggested that early frontoparietal connectivity can predict mathematic achievements; however, the study of brain connectivity during numerical processing remains unexplored. With the aim of evaluating this in children with different math proficiencies, we selected a sample of 40 children divided into two groups [high achievement (HA) and low achievement (LA)] according to their arithmetic scores in the Wide Range Achievement Test, 4th ed.. Participants performed a symbolic magnitude comparison task (i.e. determining which of two numbers is numerically larger), with simultaneous electrophysiological recording. Partial directed coherence and graph theory methods were used to estimate and depict frontoparietal connectivity in both groups. The behavioral measures showed that children with LA performed significantly slower and less accurately than their peers in the HA group. Significantly higher frontocentral connectivity was found in LA compared with HA; however, when the connectivity analysis was restricted to parietal locations, no relevant group differences were observed. These findings seem to support the notion that LA children require greater memory and attentional efforts to meet task demands, probably affecting early stages of symbolic comparison.

Relations of different types of numerical magnitude representations to each other and to mathematics achievement.

PubMed

Fazio, Lisa K; Bailey, Drew H; Thompson, Clarissa A; Siegler, Robert S

2014-07-01

We examined relations between symbolic and non-symbolic numerical magnitude representations, between whole number and fraction representations, and between these representations and overall mathematics achievement in fifth graders. Fraction and whole number symbolic and non-symbolic numerical magnitude understandings were measured using both magnitude comparison and number line estimation tasks. After controlling for non-mathematical cognitive proficiency, both symbolic and non-symbolic numerical magnitude understandings were uniquely related to mathematics achievement, but the relation was much stronger for symbolic numbers. A meta-analysis of 19 published studies indicated that relations between non-symbolic numerical magnitude knowledge and mathematics achievement are present but tend to be weak, especially beyond 6 years of age. Copyright © 2014 Elsevier Inc. All rights reserved.

Subjective scaling of mental workload in a multi-task environment

NASA Technical Reports Server (NTRS)

Daryanian, B.

1982-01-01

Those factors in a multi-task environment that contribute to the operators' "sense" of mental workload were identified. The subjective judgment as conscious experience of mental effort was decided to be the appropriate method of measurement. Thurstone's law of comparative judgment was employed in order to construct interval scales of subjective mental workload from paired comparisons data. An experimental paradigm (Simulated Multi-Task Decision-Making Environment) was employed to represent the ideal experimentally controlled environment in which human operators were asked to "attend" to different cases of Tulga's decision making tasks. Through various statistical analyses it was found that, in general, a lower number of tasks-to-be-processed per unit time (a condition associated with longer interarrival times), results in a lower mental workload, a higher consistency of judgments within a subject, a higher degree of agreement among the subjects, and larger distances between the cases on the Thurstone scale of subjective mental workload. The effects of various control variables and their interactions, and the different characteristics of the subjects on the variation of subjective mental workload are demonstrated.

Objective comparison of particle tracking methods.

PubMed

Chenouard, Nicolas; Smal, Ihor; de Chaumont, Fabrice; Maška, Martin; Sbalzarini, Ivo F; Gong, Yuanhao; Cardinale, Janick; Carthel, Craig; Coraluppi, Stefano; Winter, Mark; Cohen, Andrew R; Godinez, William J; Rohr, Karl; Kalaidzidis, Yannis; Liang, Liang; Duncan, James; Shen, Hongying; Xu, Yingke; Magnusson, Klas E G; Jaldén, Joakim; Blau, Helen M; Paul-Gilloteaux, Perrine; Roudot, Philippe; Kervrann, Charles; Waharte, François; Tinevez, Jean-Yves; Shorte, Spencer L; Willemse, Joost; Celler, Katherine; van Wezel, Gilles P; Dan, Han-Wei; Tsai, Yuh-Show; Ortiz de Solórzano, Carlos; Olivo-Marin, Jean-Christophe; Meijering, Erik

2014-03-01

Particle tracking is of key importance for quantitative analysis of intracellular dynamic processes from time-lapse microscopy image data. Because manually detecting and following large numbers of individual particles is not feasible, automated computational methods have been developed for these tasks by many groups. Aiming to perform an objective comparison of methods, we gathered the community and organized an open competition in which participating teams applied their own methods independently to a commonly defined data set including diverse scenarios. Performance was assessed using commonly defined measures. Although no single method performed best across all scenarios, the results revealed clear differences between the various approaches, leading to notable practical conclusions for users and developers.

Alcohol consumption impairs stimulus- and error-related processing during a Go/No-Go Task.

PubMed

Easdon, Craig; Izenberg, Aaron; Armilio, Maria L; Yu, He; Alain, Claude

2005-12-01

Alcohol consumption has been shown to increase the number of errors in tasks that require a high degree of cognitive control, such as a go/no-go task. The alcohol-related decline in performance may be related to difficulties in maintaining attention on the task at hand and/or deficits in inhibiting a prepotent response. To test these two accounts, we investigated the effects of alcohol on stimulus- and response-locked evoked potentials recorded during a go/no-go task that involved the withholding of key presses to rare targets. All participants performed the task prior to drinking and were then assigned randomly to either a control, low-dose, or moderate-dose treatment. Both doses of alcohol increased the number of errors relative to alcohol-free performance. Success in withholding a prepotent response was associated with an early-enhanced stimulus-locked negativity at inferior parietal sites, which was delayed when participants failed to inhibit the motor command. Moreover, low and moderate doses of alcohol reduced N170 and P3 amplitudes during go, no-go, and error trials. In comparison with the correct responses, errors generated large response-locked negative (Ne) and positive (Pe) waves at central sites. Both doses of alcohol reduced the Ne amplitude whereas the Pe amplitude decreased only after moderate doses of alcohol. These results are consistent with the interpretation that behavioral disinhibition following alcohol consumption involved alcohol-induced deficits in maintaining and allocating attention thereby affecting the processing of incoming stimuli and the recognition that an errant response has been made.

Why is quality estimation judgment fast? Comparison of gaze control strategies in quality and difference estimation tasks

NASA Astrophysics Data System (ADS)

Radun, Jenni; Leisti, Tuomas; Virtanen, Toni; Nyman, Göte; Häkkinen, Jukka

2014-11-01

To understand the viewing strategies employed in a quality estimation task, we compared two visual tasks-quality estimation and difference estimation. The estimation was done for a pair of natural images having small global changes in quality. Two groups of observers estimated the same set of images, but with different instructions. One group estimated the difference in quality and the other the difference between image pairs. The results demonstrated the use of different visual strategies in the tasks. The quality estimation was found to include more visual planning during the first fixation than the difference estimation, but afterward needed only a few long fixations on the semantically important areas of the image. The difference estimation used many short fixations. Salient image areas were mainly attended to when these areas were also semantically important. The results support the hypothesis that these tasks' general characteristics (evaluation time, number of fixations, area fixated on) show differences in processing, but also suggest that examining only single fixations when comparing tasks is too narrow a view. When planning a subjective experiment, one must remember that a small change in the instructions might lead to a noticeable change in viewing strategy.

Decision paths in complex tasks

NASA Technical Reports Server (NTRS)

Galanter, Eugene

1991-01-01

Complex real world action and its prediction and control has escaped analysis by the classical methods of psychological research. The reason is that psychologists have no procedures to parse complex tasks into their constituents. Where such a division can be made, based say on expert judgment, there is no natural scale to measure the positive or negative values of the components. Even if we could assign numbers to task parts, we lack rules i.e., a theory, to combine them into a total task representation. We compare here two plausible theories for the amalgamation of the value of task components. Both of these theories require a numerical representation of motivation, for motivation is the primary variable that guides choice and action in well-learned tasks. We address this problem of motivational quantification and performance prediction by developing psychophysical scales of the desireability or aversiveness of task components based on utility scaling methods (Galanter 1990). We modify methods used originally to scale sensory magnitudes (Stevens and Galanter 1957), and that have been applied recently to the measure of task 'workload' by Gopher and Braune (1984). Our modification uses utility comparison scaling techniques which avoid the unnecessary assumptions made by Gopher and Braune. Formula for the utility of complex tasks based on the theoretical models are used to predict decision and choice of alternate paths to the same goal.

Brain activity across the development of automatic categorization: A comparison of categorization tasks using multi-voxel pattern analysis

PubMed Central

Soto, Fabian A.; Waldschmidt, Jennifer G.; Helie, Sebastien; Ashby, F. Gregory

2013-01-01

Previous evidence suggests that relatively separate neural networks underlie initial learning of rule-based and information-integration categorization tasks. With the development of automaticity, categorization behavior in both tasks becomes increasingly similar and exclusively related to activity in cortical regions. The present study uses multi-voxel pattern analysis to directly compare the development of automaticity in different categorization tasks. Each of three groups of participants received extensive training in a different categorization task: either an information-integration task, or one of two rule-based tasks. Four training sessions were performed inside an MRI scanner. Three different analyses were performed on the imaging data from a number of regions of interest (ROIs). The common patterns analysis had the goal of revealing ROIs with similar patterns of activation across tasks. The unique patterns analysis had the goal of revealing ROIs with dissimilar patterns of activation across tasks. The representational similarity analysis aimed at exploring (1) the similarity of category representations across ROIs and (2) how those patterns of similarities compared across tasks. The results showed that common patterns of activation were present in motor areas and basal ganglia early in training, but only in the former later on. Unique patterns were found in a variety of cortical and subcortical areas early in training, but they were dramatically reduced with training. Finally, patterns of representational similarity between brain regions became increasingly similar across tasks with the development of automaticity. PMID:23333700

Other better versus self better in baboons: an evolutionary approach of social comparison

PubMed Central

2017-01-01

Comparing oneself with others is an important characteristic of human social life, but the link between human and non-human forms of social comparison remains largely unknown. The present study used a computerized task presented in a social context to explore psychological mechanisms supporting social comparison in baboons and compare major findings with those usually observed in humans. We found that the effects of social comparison on subject's performance were guided both by similarity (same versus different sex) and by task complexity. Comparing oneself with a better-off other (upward comparison) increased performance when the other was similar rather than dissimilar, and a reverse effect was obtained when the self was better (downward comparison). Furthermore, when the other was similar, upward comparison led to a better performance than downward comparison. Interestingly, the beneficial effect of upward comparison on baboons' performance was only observed during simple task. Our results support the hypothesis of shared social comparison mechanisms in human and non-human primates. PMID:28539512

Effects of Healthy Aging and Mild Cognitive Impairment on a Real-Life Decision-Making Task.

PubMed

Pertl, Marie-Theres; Benke, Thomas; Zamarian, Laura; Delazer, Margarete

2017-01-01

In this study, we investigated the effects of age and of mild cognitive impairment (MCI) on decision making under risk by adopting a task representing real-life health-related situations and involving complex numerical information. Moreover, we assessed the relationship of real-life decision making to other cognitive functions such as number processing, executive functions, language, memory, and attention. For this reason, we compared the performance of 19 healthy, relatively younger adults with that of 18 healthy older adults and the performance of the 18 healthy older adults with that of 17 patients with MCI. Results indicated difficulties in real-life decision making for the healthy older adults compared with the healthy, relatively younger adults. Difficulties of patients with MCI relative to the healthy older adults arose in particular in difficult items requiring processing of frequencies and fractions. Significant effects of age and of MCI in processing frequencies were also evident in a ratio number comparison task. Decision-making performance of healthy participants and of the patient group correlated significantly with number processing. There was a further significant correlation with executive functions for the healthy participants and with reading comprehension for the patients. Our results suggest that healthy older individuals and patients with MCI make less advantageous decisions when the information is complex and high demands are put on executive functions and numerical abilities. Moreover, we show that executive functions and numerical abilities are not only essential in laboratory gambling tasks but also in more realistic and ecological decision situations within the health context.

Vibrotactile neurofeedback balance training in patients with Parkinson's disease: reducing the number of falls.

PubMed

Rossi-Izquierdo, Marcos; Ernst, Arne; Soto-Varela, Andrés; Santos-Pérez, Sofía; Faraldo-García, Ana; Sesar-Ignacio, Angel; Basta, Dietmar

2013-02-01

The aim of this study was to assess effectiveness of balance training with a vibrotactile neurofeedback system in improving overall stability in patients with Parkinson's disease (PD). Ten patients diagnosed with idiopathic PD were included. Individualization of the rehabilitation program started with a body sway analysis of stance and gait tasks (Standard Balance Deficit Test, SBDT) by using the diagnostic tool of the applied device (Vertiguard(®)-RT). Those tasks with the poorest outcome as related to age- and gender-related controls were included in the training program (not more than six tasks). Improvement of postural stability was assessed by performing SBDT, Sensory Organization Test (SOT) of Computerized Dynamic Posturography (CDP), Dizziness Handicap Inventory (DHI), activity-specific balance confidence scale and recording the number of falls over the past three months. Furthermore, scores of SOT and DHI of 10 PD patients previously trained in an earlier study (by using CDP) were compared with results of those in the present study. After neurofeedback training (NFT), there was a statistically significant improvement in body sway (calculated over all training tasks), number of falls, and scores of SOT, DHI and ABC. In comparison with CDP-training, a statistically significant higher increase of SOT score was observed for patients after NFT with the Vertiguard-RT device compared to CDP training. Our results showed that a free-field vibrotactile NFT with Vertiguard(®)-RT device can improve balance in PD patients in everyday life conditions very effectively, which might led in turn to a reduction of falls. Copyright © 2012 Elsevier B.V. All rights reserved.

Comparison of Psychophysiological and Dual-Task Measures of Listening Effort

ERIC Educational Resources Information Center

Seeman, Scott; Sims, Rebecca

2015-01-01

Purpose: We wished to make a comparison of psychophysiological measures of listening effort with subjective and dual-task measures of listening effort for a diotic-dichotic-digits and a sentences-in-noise task. Method: Three groups of young adults (18-38 years old) with normal hearing participated in three experiments: two psychophysiological…

Dimension-based attention in visual short-term memory.

PubMed

Pilling, Michael; Barrett, Doug J K

2016-07-01

We investigated how dimension-based attention influences visual short-term memory (VSTM). This was done through examining the effects of cueing a feature dimension in two perceptual comparison tasks (change detection and sameness detection). In both tasks, a memory array and a test array consisting of a number of colored shapes were presented successively, interleaved by a blank interstimulus interval (ISI). In Experiment 1 (change detection), the critical event was a feature change in one item across the memory and test arrays. In Experiment 2 (sameness detection), the critical event was the absence of a feature change in one item across the two arrays. Auditory cues indicated the feature dimension (color or shape) of the critical event with 80 % validity; the cues were presented either prior to the memory array, during the ISI, or simultaneously with the test array. In Experiment 1, the cue validity influenced sensitivity only when the cue was given at the earliest position; in Experiment 2, the cue validity influenced sensitivity at all three cue positions. We attributed the greater effectiveness of top-down guidance by cues in the sameness detection task to the more active nature of the comparison process required to detect sameness events (Hyun, Woodman, Vogel, Hollingworth, & Luck, Journal of Experimental Psychology: Human Perception and Performance, 35; 1140-1160, 2009).

Safe driving and executive functions in healthy middle-aged drivers.

PubMed

León-Domínguez, Umberto; Solís-Marcos, Ignacio; Barrio-Álvarez, Elena; Barroso Y Martín, Juan Manuel; León-Carrión, José

2017-01-01

The introduction of the point system driver's license in several European countries could offer a valid framework for evaluating driving skills. This is the first study to use this framework to assess the functional integrity of executive functions in middle-aged drivers with full points, partial points or no points on their driver's license (N = 270). The purpose of this study is to find differences in executive functions that could be determinants in safe driving. Cognitive tests were used to assess attention processes, processing speed, planning, cognitive flexibility, and inhibitory control. Analyses for covariance (ANCOVAS) were used for group comparisons while adjusting for education level. The Bonferroni method was used for correcting for multiple comparisons. Overall, drivers with the full points on their license showed better scores than the other two groups. In particular, significant differences were found in reaction times on Simple and Conditioned Attention tasks (both p-values < 0.001) and in number of type-III errors on the Tower of Hanoi task (p = 0.026). Differences in reaction time on attention tasks could serve as neuropsychological markers for safe driving. Further analysis should be conducted in order to determine the behavioral impact of impaired executive functioning on driving ability.

Scaling bioinformatics applications on HPC.

PubMed

Mikailov, Mike; Luo, Fu-Jyh; Barkley, Stuart; Valleru, Lohit; Whitney, Stephen; Liu, Zhichao; Thakkar, Shraddha; Tong, Weida; Petrick, Nicholas

2017-12-28

Recent breakthroughs in molecular biology and next generation sequencing technologies have led to the expenential growh of the sequence databases. Researchrs use BLAST for processing these sequences. However traditional software parallelization techniques (threads, message passing interface) applied in newer versios of BLAST are not adequate for processing these sequences in timely manner. A new method for array job parallelization has been developed which offers O(T) theoretical speed-up in comparison to multi-threading and MPI techniques. Here T is the number of array job tasks. (The number of CPUs that will be used to complete the job equals the product of T multiplied by the number of CPUs used by a single task.) The approach is based on segmentation of both input datasets to the BLAST process, combining partial solutions published earlier (Dhanker and Gupta, Int J Comput Sci Inf Technol_5:4818-4820, 2014), (Grant et al., Bioinformatics_18:765-766, 2002), (Mathog, Bioinformatics_19:1865-1866, 2003). It is accordingly referred to as a "dual segmentation" method. In order to implement the new method, the BLAST source code was modified to allow the researcher to pass to the program the number of records (effective number of sequences) in the original database. The team also developed methods to manage and consolidate the large number of partial results that get produced. Dual segmentation allows for massive parallelization, which lifts the scaling ceiling in exciting ways. BLAST jobs that hitherto failed or slogged inefficiently to completion now finish with speeds that characteristically reduce wallclock time from 27 days on 40 CPUs to a single day using 4104 tasks, each task utilizing eight CPUs and taking less than 7 minutes to complete. The massive increase in the number of tasks when running an analysis job with dual segmentation reduces the size, scope and execution time of each task. Besides significant speed of completion, additional benefits include fine-grained checkpointing and increased flexibility of job submission. "Trickling in" a swarm of individual small tasks tempers competition for CPU time in the shared HPC environment, and jobs submitted during quiet periods can complete in extraordinarily short time frames. The smaller task size also allows the use of older and less powerful hardware. The CDRH workhorse cluster was commissioned in 2010, yet its eight-core CPUs with only 24GB RAM work well in 2017 for these dual segmentation jobs. Finally, these techniques are excitingly friendly to budget conscious scientific research organizations where probabilistic algorithms such as BLAST might discourage attempts at greater certainty because single runs represent a major resource drain. If a job that used to take 24 days can now be completed in less than an hour or on a space available basis (which is the case at CDRH), repeated runs for more exhaustive analyses can be usefully contemplated.

The symbol-grounding problem in numerical cognition: A review of theory, evidence, and outstanding questions.

PubMed

Leibovich, Tali; Ansari, Daniel

2016-03-01

How do numerical symbols, such as number words, acquire semantic meaning? This question, also referred to as the "symbol-grounding problem," is a central problem in the field of numerical cognition. Present theories suggest that symbols acquire their meaning by being mapped onto an approximate system for the nonsymbolic representation of number (Approximate Number System or ANS). In the present literature review, we first asked to which extent current behavioural and neuroimaging data support this theory, and second, to which extent the ANS, upon which symbolic numbers are assumed to be grounded, is numerical in nature. We conclude that (a) current evidence that has examined the association between the ANS and number symbols does not support the notion that number symbols are grounded in the ANS and (b) given the strong correlation between numerosity and continuous variables in nonsymbolic number processing tasks, it is next to impossible to measure the pure association between symbolic and nonsymbolic numerosity. Instead, it is clear that significant cognitive control resources are required to disambiguate numerical from continuous variables during nonsymbolic number processing. Thus, if there exists any mapping between the ANS and symbolic number, then this process of association must be mediated by cognitive control. Taken together, we suggest that studying the role of both cognitive control and continuous variables in numerosity comparison tasks will provide a more complete picture of the symbol-grounding problem. (c) 2016 APA, all rights reserved).

Adolescents with Developmental Dyscalculia Do Not Have a Generalized Magnitude Deficit - Processing of Discrete and Continuous Magnitudes.

PubMed

McCaskey, Ursina; von Aster, Michael; O'Gorman Tuura, Ruth; Kucian, Karin

2017-01-01

The link between number and space has been discussed in the literature for some time, resulting in the theory that number, space and time might be part of a generalized magnitude system. To date, several behavioral and neuroimaging findings support the notion of a generalized magnitude system, although contradictory results showing a partial overlap or separate magnitude systems are also found. The possible existence of a generalized magnitude processing area leads to the question how individuals with developmental dyscalculia (DD), known for deficits in numerical-arithmetical abilities, process magnitudes. By means of neuropsychological tests and functional magnetic resonance imaging (fMRI) we aimed to examine the relationship between number and space in typical and atypical development. Participants were 16 adolescents with DD (14.1 years) and 14 typically developing (TD) peers (13.8 years). In the fMRI paradigm participants had to perform discrete (arrays of dots) and continuous magnitude (angles) comparisons as well as a mental rotation task. In the neuropsychological tests, adolescents with dyscalculia performed significantly worse in numerical and complex visuo-spatial tasks. However, they showed similar results to TD peers when making discrete and continuous magnitude decisions during the neuropsychological tests and the fMRI paradigm. A conjunction analysis of the fMRI data revealed commonly activated higher order visual (inferior and middle occipital gyrus) and parietal (inferior and superior parietal lobe) magnitude areas for the discrete and continuous magnitude tasks. Moreover, no differences were found when contrasting both magnitude processing conditions, favoring the possibility of a generalized magnitude system. Group comparisons further revealed that dyscalculic subjects showed increased activation in domain general regions, whilst TD peers activate domain specific areas to a greater extent. In conclusion, our results point to the existence of a generalized magnitude system in the occipito-parietal stream in typical development. The detailed investigation of spatial and numerical magnitude abilities in DD reveals that the deficits in number processing and arithmetic cannot be explained with a general magnitude deficiency. Our results further indicate that multiple neuro-cognitive components might contribute to the explanation of DD.

Adolescents with Developmental Dyscalculia Do Not Have a Generalized Magnitude Deficit – Processing of Discrete and Continuous Magnitudes

PubMed Central

McCaskey, Ursina; von Aster, Michael; O’Gorman Tuura, Ruth; Kucian, Karin

2017-01-01

The link between number and space has been discussed in the literature for some time, resulting in the theory that number, space and time might be part of a generalized magnitude system. To date, several behavioral and neuroimaging findings support the notion of a generalized magnitude system, although contradictory results showing a partial overlap or separate magnitude systems are also found. The possible existence of a generalized magnitude processing area leads to the question how individuals with developmental dyscalculia (DD), known for deficits in numerical-arithmetical abilities, process magnitudes. By means of neuropsychological tests and functional magnetic resonance imaging (fMRI) we aimed to examine the relationship between number and space in typical and atypical development. Participants were 16 adolescents with DD (14.1 years) and 14 typically developing (TD) peers (13.8 years). In the fMRI paradigm participants had to perform discrete (arrays of dots) and continuous magnitude (angles) comparisons as well as a mental rotation task. In the neuropsychological tests, adolescents with dyscalculia performed significantly worse in numerical and complex visuo-spatial tasks. However, they showed similar results to TD peers when making discrete and continuous magnitude decisions during the neuropsychological tests and the fMRI paradigm. A conjunction analysis of the fMRI data revealed commonly activated higher order visual (inferior and middle occipital gyrus) and parietal (inferior and superior parietal lobe) magnitude areas for the discrete and continuous magnitude tasks. Moreover, no differences were found when contrasting both magnitude processing conditions, favoring the possibility of a generalized magnitude system. Group comparisons further revealed that dyscalculic subjects showed increased activation in domain general regions, whilst TD peers activate domain specific areas to a greater extent. In conclusion, our results point to the existence of a generalized magnitude system in the occipito-parietal stream in typical development. The detailed investigation of spatial and numerical magnitude abilities in DD reveals that the deficits in number processing and arithmetic cannot be explained with a general magnitude deficiency. Our results further indicate that multiple neuro-cognitive components might contribute to the explanation of DD. PMID:28373834

Visual Form Perception Can Be a Cognitive Correlate of Lower Level Math Categories for Teenagers

PubMed Central

Cui, Jiaxin; Zhang, Yiyun; Cheng, Dazhi; Li, Dawei; Zhou, Xinlin

2017-01-01

Numerous studies have assessed the cognitive correlates of performance in mathematics, but little research has been conducted to systematically examine the relations between visual perception as the starting point of visuospatial processing and typical mathematical performance. In the current study, we recruited 223 seventh graders to perform a visual form perception task (figure matching), numerosity comparison, digit comparison, exact computation, approximate computation, and curriculum-based mathematical achievement tests. Results showed that, after controlling for gender, age, and five general cognitive processes (choice reaction time, visual tracing, mental rotation, spatial working memory, and non-verbal matrices reasoning), visual form perception had unique contributions to numerosity comparison, digit comparison, and exact computation, but had no significant relation with approximate computation or curriculum-based mathematical achievement. These results suggest that visual form perception is an important independent cognitive correlate of lower level math categories, including the approximate number system, digit comparison, and exact computation. PMID:28824513

Perceived Dentist and Dental Hygienist Task Distribution After Dental and Dental Hygiene Students' Team Intervention.

PubMed

Reinders, Jan J; Krijnen, Wim P; Stegenga, Boudewijn; van der Schans, Cees P

2017-04-01

Attitudes of dental students regarding the provision of treatment tend to be dentist-centered; however, facilitating mixed student group formation could change such perceptions. The aim of this study was to investigate the perceived scope of practice of dental and dental hygiene students and whether their perceptions of task distribution between dentists and dental hygienists would change following an educational intervention consisting of feedback, intergroup comparison, and competition between mixed-group teams. The study employed a pretest-posttest single group design. Third-year dental students and second-year dental hygiene students at a university in The Netherlands were randomly assigned to intraprofessional teams (four or five members) and received team-based performance feedback and comparison. The intervention was finalized with an award ceremony for the best intraprofessional team. Before and after the intervention, students completed a questionnaire measuring their perceived distribution of ten tasks between dentists and dental hygienists. A total of 38 dental students and 32 dental hygiene students participated in the intervention-all 70 of those eligible. Questionnaires were completed by a total 88.4% (n=61) of the participants: 34 dental (89.5%) and 27 dental hygiene students (84.4%). Dental and dental hygiene students had similar perceptions regarding teeth cleaning (prophylaxis) (p=0.372, p=0.404) and, after the intervention, preventive tasks (p=0.078). Following the intervention, dental students considered four out of ten tasks as less dentist-centered: radiograph for periodontal diagnosis (p=0.003), local anesthesia (p=0.037), teeth cleaning (p=0.037), and periodontal treatment (p=0.045). Dental hygiene students perceived one task as being less dentist-centered after the intervention: radiograph for cariologic diagnosis (p=0.041). This study found that these dental and dental hygiene students had different opinions regarding the scope of practice for dentistry and dental hygiene. The number of redistributed tasks after the intervention was especially substantial among the dental students, although the amount of change per task was minimal. Half of all tasks were perceived as less dentist-centered as a result of the intervention.

Interaction between numbers and size during visual search.

PubMed

Krause, Florian; Bekkering, Harold; Pratt, Jay; Lindemann, Oliver

2017-05-01

The current study investigates an interaction between numbers and physical size (i.e. size congruity) in visual search. In three experiments, participants had to detect a physically large (or small) target item among physically small (or large) distractors in a search task comprising single-digit numbers. The relative numerical size of the digits was varied, such that the target item was either among the numerically large or small numbers in the search display and the relation between numerical and physical size was either congruent or incongruent. Perceptual differences of the stimuli were controlled by a condition in which participants had to search for a differently coloured target item with the same physical size and by the usage of LCD-style numbers that were matched in visual similarity by shape transformations. The results of all three experiments consistently revealed that detecting a physically large target item is significantly faster when the numerical size of the target item is large as well (congruent), compared to when it is small (incongruent). This novel finding of a size congruity effect in visual search demonstrates an interaction between numerical and physical size in an experimental setting beyond typically used binary comparison tasks, and provides important new evidence for the notion of shared cognitive codes for numbers and sensorimotor magnitudes. Theoretical consequences for recent models on attention, magnitude representation and their interactions are discussed.

What Explains Doctors’ Usage of Mobile Information and Communication Technologies? A Comparison of US and Portuguese Hospitals

PubMed Central

Martins, Henrique MG; Jones, Matthew R

2005-01-01

Doctors, either as a result of individual initiative or departmental policy, may use a number of different mobile computers. The relationship between device ownership/provision and usage is, however, rarely discussed. This paper therefore presents survey data (N=267) on mobile computer ownership and use by doctors in two Portuguese and two US hospitals, considering both devices owned by individuals and those supplied by the hospital. The results show that ownership is not clearly related to either usage pattern or frequency of use. Providing handheld computers also did not lead to higher number of users, higher frequency of use or significant differences in tasks carried out. Nevertheless, doctors owning handhelds alone or in combination with laptops used them more frequently than those using laptops alone. Differences in usage pattern proportions rather than demographics were a better indication of differences in usage frequencies and the tasks for which MICT devices were being used. PMID:16779089

What explains doctors' usage of Mobile Information and Communication Technologies? A comparison of US and Portuguese hospitals.

PubMed

Martins, Henrique M G; Jones, Matthew R

2005-01-01

Doctors, either as a result of individual initiative or departmental policy, may use a number of different mobile computers. The relationship between device ownership/provision and usage is, however, rarely discussed. This paper therefore presents survey data (N=267) on mobile computer ownership and use by doctors in two Portuguese and two US hospitals, considering both devices owned by individuals and those supplied by the hospital. The results show that ownership is not clearly related to either usage pattern or frequency of use. Providing handheld computers also did not lead to higher number of users, higher frequency of use or significant differences in tasks carried out. Nevertheless, doctors owning handhelds alone or in combination with laptops used them more frequently than those using laptops alone. Differences in usage pattern proportions rather than demographics were a better indication of differences in usage frequencies and the tasks for which MICT devices were being used.

Objective comparison of particle tracking methods

PubMed Central

Chenouard, Nicolas; Smal, Ihor; de Chaumont, Fabrice; Maška, Martin; Sbalzarini, Ivo F.; Gong, Yuanhao; Cardinale, Janick; Carthel, Craig; Coraluppi, Stefano; Winter, Mark; Cohen, Andrew R.; Godinez, William J.; Rohr, Karl; Kalaidzidis, Yannis; Liang, Liang; Duncan, James; Shen, Hongying; Xu, Yingke; Magnusson, Klas E. G.; Jaldén, Joakim; Blau, Helen M.; Paul-Gilloteaux, Perrine; Roudot, Philippe; Kervrann, Charles; Waharte, François; Tinevez, Jean-Yves; Shorte, Spencer L.; Willemse, Joost; Celler, Katherine; van Wezel, Gilles P.; Dan, Han-Wei; Tsai, Yuh-Show; de Solórzano, Carlos Ortiz; Olivo-Marin, Jean-Christophe; Meijering, Erik

2014-01-01

Particle tracking is of key importance for quantitative analysis of intracellular dynamic processes from time-lapse microscopy image data. Since manually detecting and following large numbers of individual particles is not feasible, automated computational methods have been developed for these tasks by many groups. Aiming to perform an objective comparison of methods, we gathered the community and organized, for the first time, an open competition, in which participating teams applied their own methods independently to a commonly defined data set including diverse scenarios. Performance was assessed using commonly defined measures. Although no single method performed best across all scenarios, the results revealed clear differences between the various approaches, leading to important practical conclusions for users and developers. PMID:24441936

Comparison of de novo assembly statistics of Cucumis sativus L.

NASA Astrophysics Data System (ADS)

Wojcieszek, Michał; Kuśmirek, Wiktor; Pawełkowicz, Magdalena; PlÄ der, Wojciech; Nowak, Robert M.

2017-08-01

Genome sequencing is the core of genomic research. With the development of NGS and lowering the cost of procedure there is another tight gap - genome assembly. Developing the proper tool for this task is essential as quality of genome has important impact on further research. Here we present comparison of several de Bruijn assemblers tested on C. sativus genomic reads. The assessment shows that newly developed software - dnaasm provides better results in terms of quantity and quality. The number of generated sequences is lower by 5 - 33% with even two fold higher N50. Quality check showed reliable results were generated by dnaasm. This provides us with very strong base for future genomic analysis.

The influence of time units on the flexibility of the spatial numerical association of response codes effect.

PubMed

Zhao, Tingting; He, Xianyou; Zhao, Xueru; Huang, Jianrui; Zhang, Wei; Wu, Shuang; Chen, Qi

2018-05-01

The Spatial Numerical/Temporal Association of Response Codes (SNARC/STEARC) effects are considered evidence of the association between number or time and space, respectively. As the SNARC effect was proposed by Dehaene, Bossini, and Giraux in 1993, several studies have suggested that different tasks and cultural factors can affect the flexibility of the SNARC effect. This study explored the influence of time units on the flexibility of the SNARC effect via materials with Arabic numbers, which were suffixed with time units and subjected to magnitude comparison tasks. Experiment 1 replicated the SNARC effect for numbers and the STEARC effect for time units. Experiment 2 explored the flexibility of the SNARC effect when numbers were attached to time units, which either conflicted with the numerical magnitude or in which the time units were the same or different. Experiment 3 explored whether the SNARC effect of numbers was stable when numbers were near the transition of two adjacent time units. The results indicate that the SNARC effect was flexible when the numbers were suffixed with time units: Time units influenced the direction of the SNARC effect in a way which could not be accounted for by the mathematical differences between the time units and numbers. This suggests that the SNARC effect is not obligatory and can be easily adapted or inhibited based on the current context. © 2017 The Authors. British Journal of Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

A comparison of spontaneous problem-solving abilities in three estrildid finch (Taeniopygia guttata, Lonchura striata var. domestica, Stagonopleura guttata) species.

PubMed

Schmelz, Martin; Krüger, Oliver; Call, Josep; Krause, E Tobias

2015-11-01

Cognition has been extensively studied in primates while other, more distantly related taxa have been neglected for a long time. More recently, there has been an increased interest in avian cognition, with the focus mostly on big-brained species like parrots and corvids. However, the majority of bird species has never systematically been studied in diverse cognitive tasks other than memory and learning tasks, so not much can yet be concluded about the relevant factors for the evolution of cognition. Here we examined 3 species of the estrildid finch family in problem-solving tasks. These granivorous, non-tool-using birds are distributed across 3 continents and are not known for high levels of innovation or spontaneous problem solving in the wild. In this study, our aim was to find such abilities in these species, assess what role domestication might play with a comparison of 4 genetically separated zebra finch strains, and to look for between-species differences between zebra finches, Bengalese finches, and diamond firetails. Furthermore, we established a 3-step spontaneous problem-solving procedure with increasing levels of complexity. Results showed that some estrildid finches were generally capable of spontaneously solving problems of variable complexity to obtain food. We found striking differences in these abilities between species, but not between strains within species, and offer a discussion of potential reasons. Our established methodology can now be applied to a larger number of bird species for phylogenetic comparisons on the behavioral level to get a deeper understanding of the evolution of cognitive abilities. (c) 2015 APA, all rights reserved).

A New Measure for Neural Compensation Is Positively Correlated With Working Memory and Gait Speed.

PubMed

Ji, Lanxin; Pearlson, Godfrey D; Hawkins, Keith A; Steffens, David C; Guo, Hua; Wang, Lihong

2018-01-01

Neuroimaging studies suggest that older adults may compensate for declines in brain function and cognition through reorganization of neural resources. A limitation of prior research is reliance on between-group comparisons of neural activation (e.g., younger vs. older), which cannot be used to assess compensatory ability quantitatively. It is also unclear about the relationship between compensatory ability with cognitive function or how other factors such as physical exercise modulates compensatory ability. Here, we proposed a data-driven method to semi-quantitatively measure neural compensation under a challenging cognitive task, and we then explored connections between neural compensation to cognitive engagement and cognitive reserve (CR). Functional and structural magnetic resonance imaging scans were acquired for 26 healthy older adults during a face-name memory task. Spatial independent component analysis (ICA) identified visual, attentional and left executive as core networks. Results show that the smaller the volumes of the gray matter (GM) structures within core networks, the more networks were needed to conduct the task ( r = -0.408, p = 0.035). Therefore, the number of task-activated networks controlling for the GM volume within core networks was defined as a measure of neural compensatory ability. We found that compensatory ability correlated with working memory performance ( r = 0.528, p = 0.035). Among subjects with good memory task performance, those with higher CR used fewer networks than subjects with lower CR. Among poor-performance subjects, those using more networks had higher CR. Our results indicated that using a high cognitive-demanding task to measure the number of activated neural networks could be a useful and sensitive measure of neural compensation in older adults.

A Diffusion Model Analysis of Magnitude Comparison in Children with and without Dyscalculia: Care of Response and Ability Are Related to Both Mathematical Achievement and Stimuli.

PubMed

Szardenings, Carsten; Kuhn, Jörg-Tobias; Ranger, Jochen; Holling, Heinz

2017-01-01

The respective roles of the approximate number system (ANS) and an access deficit (AD) in developmental dyscalculia (DD) are not well-known. Most studies rely on response times (RTs) or accuracy (error rates) separately. We analyzed the results of two samples of elementary school children in symbolic magnitude comparison (MC) and non-symbolic MC using a diffusion model. This approach uses the joint distribution of both RTs and accuracy in order to synthesize measures closer to ability and response caution or response conservatism. The latter can be understood in the context of the speed-accuracy tradeoff: It expresses how much a subject trades in speed for improved accuracy. We found significant effects of DD on both ability (negative) and response caution (positive) in MC tasks and a negative interaction of DD with symbolic task material on ability. These results support that DD subjects suffer from both an impaired ANS and an AD and in particular support that slower RTs of children with DD are indeed related to impaired processing of numerical information. An interaction effect of symbolic task material and DD (low mathematical ability) on response caution could not be refuted. However, in a sample more representative of the general population we found a negative association of mathematical ability and response caution in symbolic but not in non-symbolic task material. The observed differences in response behavior highlight the importance of accounting for response caution in the analysis of MC tasks. The results as a whole present a good example of the benefits of a diffusion model analysis.

A Diffusion Model Analysis of Magnitude Comparison in Children with and without Dyscalculia: Care of Response and Ability Are Related to Both Mathematical Achievement and Stimuli

PubMed Central

Szardenings, Carsten; Kuhn, Jörg-Tobias; Ranger, Jochen; Holling, Heinz

2018-01-01

The respective roles of the approximate number system (ANS) and an access deficit (AD) in developmental dyscalculia (DD) are not well-known. Most studies rely on response times (RTs) or accuracy (error rates) separately. We analyzed the results of two samples of elementary school children in symbolic magnitude comparison (MC) and non-symbolic MC using a diffusion model. This approach uses the joint distribution of both RTs and accuracy in order to synthesize measures closer to ability and response caution or response conservatism. The latter can be understood in the context of the speed-accuracy tradeoff: It expresses how much a subject trades in speed for improved accuracy. We found significant effects of DD on both ability (negative) and response caution (positive) in MC tasks and a negative interaction of DD with symbolic task material on ability. These results support that DD subjects suffer from both an impaired ANS and an AD and in particular support that slower RTs of children with DD are indeed related to impaired processing of numerical information. An interaction effect of symbolic task material and DD (low mathematical ability) on response caution could not be refuted. However, in a sample more representative of the general population we found a negative association of mathematical ability and response caution in symbolic but not in non-symbolic task material. The observed differences in response behavior highlight the importance of accounting for response caution in the analysis of MC tasks. The results as a whole present a good example of the benefits of a diffusion model analysis. PMID:29379450

The evolution of face processing in primates

PubMed Central

Parr, Lisa A.

2011-01-01

The ability to recognize faces is an important socio-cognitive skill that is associated with a number of cognitive specializations in humans. While numerous studies have examined the presence of these specializations in non-human primates, species where face recognition would confer distinct advantages in social situations, results have been mixed. The majority of studies in chimpanzees support homologous face-processing mechanisms with humans, but results from monkey studies appear largely dependent on the type of testing methods used. Studies that employ passive viewing paradigms, like the visual paired comparison task, report evidence of similarities between monkeys and humans, but tasks that use more stringent, operant response tasks, like the matching-to-sample task, often report species differences. Moreover, the data suggest that monkeys may be less sensitive than chimpanzees and humans to the precise spacing of facial features, in addition to the surface-based cues reflected in those features, information that is critical for the representation of individual identity. The aim of this paper is to provide a comprehensive review of the available data from face-processing tasks in non-human primates with the goal of understanding the evolution of this complex cognitive skill. PMID:21536559

One Task, Divergent Solutions: High- versus Low-Status Sources and Social Comparison Guide Adaptation in a Computer-Supported Socio-Cognitive Conflict Task

ERIC Educational Resources Information Center

Baumeister, Antonia E.; Engelmann, Tanja; Hesse, Friedrich W.

2017-01-01

This experimental study extends conflict elaboration theory (1) by revealing social influence dynamics for a knowledge-rich computer-supported socio-cognitive conflict task not investigated in the context of this theory before and (2) by showing the impact of individual differences in social comparison orientation. Students in two conditions…

A coordinate-based ALE functional MRI meta-analysis of brain activation during verbal fluency tasks in healthy control subjects

PubMed Central

2014-01-01

Background The processing of verbal fluency tasks relies on the coordinated activity of a number of brain areas, particularly in the frontal and temporal lobes of the left hemisphere. Recent studies using functional magnetic resonance imaging (fMRI) to study the neural networks subserving verbal fluency functions have yielded divergent results especially with respect to a parcellation of the inferior frontal gyrus for phonemic and semantic verbal fluency. We conducted a coordinate-based activation likelihood estimation (ALE) meta-analysis on brain activation during the processing of phonemic and semantic verbal fluency tasks involving 28 individual studies with 490 healthy volunteers. Results For phonemic as well as for semantic verbal fluency, the most prominent clusters of brain activation were found in the left inferior/middle frontal gyrus (LIFG/MIFG) and the anterior cingulate gyrus. BA 44 was only involved in the processing of phonemic verbal fluency tasks, BA 45 and 47 in the processing of phonemic and semantic fluency tasks. Conclusions Our comparison of brain activation during the execution of either phonemic or semantic verbal fluency tasks revealed evidence for spatially different activation in BA 44, but not other regions of the LIFG/LMFG (BA 9, 45, 47) during phonemic and semantic verbal fluency processing. PMID:24456150

[Worrying and performance on the Stroop task in women].

PubMed

Janowski, Konrad; Kaczmarek, Łukasz; Kossowska, Magdalena; Niedbał, Kornelia

2009-01-01

Worrying is a process involving chronic, repetitive activation of unproductive thought chains whose contents are predominantly characterized by anticipation of future outcomes undesirable for the individual. Numerous studies demonstrated the role of excessive worrying in the patomechanisms of general anxiety disorder and depression as well as its associations with several non-adaptative aspects of functioning. Some neuroimaging studies suggested an association of worrying with frontal cortex activity. The objective of this study was to assess the associations of worrying with the frontal lobe functions, as measured by the Stroop Task. Fifty female students took part in the study. Each participant completed the Penn State Worry Questionnaire (PSQW), a psychometric measure of worrying tendencies, and performed on the Color Words Stroop Task. No statistically significant associations were found between the worrying levels and response times on the Stroop Task. However, worrying was found to be statistically significantly related to the number of errors committed on the Stroop Task, with women characterized by higher worrying levels, making approximately two-fold fewer errors in comparison to women with lower worrying levels. In women, higher worrying levels may be associated with a qualitatively better performance on some mental tasks, which may probably be accounted for by the involvement of higher attentional readiness or personality traits, such as perfectionism.

Comparison of Perimeters: Improving Students' Performance by Increasing the Salience of the Relevant Variable

ERIC Educational Resources Information Center

Babai, Reuven; Nattiv, Laura; Stavy, Ruth

2016-01-01

Students' difficulties in mathematics and science may stem from interference of irrelevant salient variables. We focus on the comparison of perimeters task, in which area is the irrelevant salient variable. A previous fMRI brain-imaging study related to the comparison of perimeters task suggested that increasing the level of salience of the…

PIPI: PTM-Invariant Peptide Identification Using Coding Method.

PubMed

Yu, Fengchao; Li, Ning; Yu, Weichuan

2016-12-02

In computational proteomics, the identification of peptides with an unlimited number of post-translational modification (PTM) types is a challenging task. The computational cost associated with database search increases exponentially with respect to the number of modified amino acids and linearly with respect to the number of potential PTM types at each amino acid. The problem becomes intractable very quickly if we want to enumerate all possible PTM patterns. To address this issue, one group of methods named restricted tools (including Mascot, Comet, and MS-GF+) only allow a small number of PTM types in database search process. Alternatively, the other group of methods named unrestricted tools (including MS-Alignment, ProteinProspector, and MODa) avoids enumerating PTM patterns with an alignment-based approach to localizing and characterizing modified amino acids. However, because of the large search space and PTM localization issue, the sensitivity of these unrestricted tools is low. This paper proposes a novel method named PIPI to achieve PTM-invariant peptide identification. PIPI belongs to the category of unrestricted tools. It first codes peptide sequences into Boolean vectors and codes experimental spectra into real-valued vectors. For each coded spectrum, it then searches the coded sequence database to find the top scored peptide sequences as candidates. After that, PIPI uses dynamic programming to localize and characterize modified amino acids in each candidate. We used simulation experiments and real data experiments to evaluate the performance in comparison with restricted tools (i.e., Mascot, Comet, and MS-GF+) and unrestricted tools (i.e., Mascot with error tolerant search, MS-Alignment, ProteinProspector, and MODa). Comparison with restricted tools shows that PIPI has a close sensitivity and running speed. Comparison with unrestricted tools shows that PIPI has the highest sensitivity except for Mascot with error tolerant search and ProteinProspector. These two tools simplify the task by only considering up to one modified amino acid in each peptide, which results in a higher sensitivity but has difficulty in dealing with multiple modified amino acids. The simulation experiments also show that PIPI has the lowest false discovery proportion, the highest PTM characterization accuracy, and the shortest running time among the unrestricted tools.

[Physicians' tasks in the Occupational Health Services].

PubMed

von Bülow, B A

1995-03-06

The aim of this study was to describe the kind of present and future tasks doctors employed in the Occupational Health Service (OHS) in Denmark carried out and to shed light on the reasons why only a moderate number of doctors are employed in the OHS. Additional aims were to map out the number of engaged part-time and full-time doctors in the OHS in Denmark compared with the number of other professionals engaged in the OHS. The study was based on questionnaires sent out to all 109 OHS units in Denmark and to all the doctors employed in the OHS. Ten persons in the OHS were strategically selected for an open interview. There were still only a very few doctors (9%) employed in the OHS in comparison to the other professionals employed in OHS, (nurses, various therapists and technicians) and the doctors were mostly engaged part-time; most of them for less than 10 hours a week. The moderate number of doctors was amongst other things explained by the relatively high cost of the doctors' salaries and the doctors having a reputation for being arrogant and dominating. The doctors were in general very experienced in occupational health matters and solved many problems which required a doctors education. A great deal of the problems they solved were in finding the causality between the workers' symptoms and the working-place conditions. The doctors suggested several future tasks for OHS, e.g. to evaluate its preventive results and to participate in a higher degree when planning working environments.

Baseline experiments in teleoperator control

NASA Technical Reports Server (NTRS)

Hankins, W. W., III; Mixon, R. W.

1986-01-01

Studies have been conducted at the NASA Langley Research Center (LaRC) to establish baseline human teleoperator interface data and to assess the influence of some of the interface parameters on human performance in teleoperation. As baseline data, the results will be used to assess future interface improvements resulting from this research in basic teleoperator human factors. In addition, the data have been used to validate LaRC's basic teleoperator hardware setup and to compare initial teleoperator study results. Four subjects controlled a modified industrial manipulator to perform a simple task involving both high and low precision. Two different schemes for controlling the manipulator were studied along with both direct and indirect viewing of the task. Performance of the task was measured as the length of time required to complete the task along with the number of errors made in the process. Analyses of variance were computed to determine the significance of the influences of each of the independent variables. Comparisons were also made between the LaRC data and data taken earlier by Grumman Aerospace Corp. at their facilities.

Telerobotics - Display, control, and communication problems

NASA Technical Reports Server (NTRS)

Stark, Lawrence; Kim, Won-Soo; Tendick, Frank; Hannaford, Blake; Ellis, Stephen

1987-01-01

An experimental telerobotics simulation is described suitable for studying human operator (HO) performance. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. An enhanced perspective display was effective with a reference line from target to base, with or without a complex three-dimensional grid framing the view. This was true especially if geometrical display parameters such as azimuth and elevation were arranged to be near optimal. Quantitative comparisons were made possible, utilizing control performance measures such as root mean square error. There was a distinct preference for controlling the manipulator in end-effector Cartesian space for the primitive pick-and-place task, rather than controlling joint angles and then, via direct kinematis, the end-effector position. An introduced communication delay was found to produce decrease in performance. In considerable part, this difficulty could be compensated for by preview control information. The fact that neurological control of normal human movement contains a sampled data period of 0.2 s may relate to this robustness of HO control to delay.

No psychological effect of color context in a low level vision task

PubMed Central

Pedley, Adam; Wade, Alex R

2013-01-01

Background: A remarkable series of recent papers have shown that colour can influence performance in cognitive tasks. In particular, they suggest that viewing a participant number printed in red ink or other red ancillary stimulus elements improves performance in tasks requiring local processing and impedes performance in tasks requiring global processing whilst the reverse is true for the colour blue. The tasks in these experiments require high level cognitive processing such as analogy solving or remote association tests and the chromatic effect on local vs. global processing is presumed to involve widespread activation of the autonomic nervous system. If this is the case, we might expect to see similar effects on all local vs. global task comparisons. To test this hypothesis, we asked whether chromatic cues also influence performance in tasks involving low level visual feature integration. Methods: Subjects performed either local (contrast detection) or global (form detection) tasks on achromatic dynamic Glass pattern stimuli. Coloured instructions, target frames and fixation points were used to attempt to bias performance to different task types. Based on previous literature, we hypothesised that red cues would improve performance in the (local) contrast detection task but would impede performance in the (global) form detection task.  Results: A two-way, repeated measures, analysis of covariance (2×2 ANCOVA) with gender as a covariate, revealed no influence of colour on either task, F(1,29) = 0.289, p = 0.595, partial η 2 = 0.002. Additional analysis revealed no significant differences in only the first attempts of the tasks or in the improvement in performance between trials. Discussion: We conclude that motivational processes elicited by colour perception do not influence neuronal signal processing in the early visual system, in stark contrast to their putative effects on processing in higher areas. PMID:25075280

No psychological effect of color context in a low level vision task.

PubMed

Pedley, Adam; Wade, Alex R

2013-01-01

A remarkable series of recent papers have shown that colour can influence performance in cognitive tasks. In particular, they suggest that viewing a participant number printed in red ink or other red ancillary stimulus elements improves performance in tasks requiring local processing and impedes performance in tasks requiring global processing whilst the reverse is true for the colour blue. The tasks in these experiments require high level cognitive processing such as analogy solving or remote association tests and the chromatic effect on local vs. global processing is presumed to involve widespread activation of the autonomic nervous system. If this is the case, we might expect to see similar effects on all local vs. global task comparisons. To test this hypothesis, we asked whether chromatic cues also influence performance in tasks involving low level visual feature integration. Subjects performed either local (contrast detection) or global (form detection) tasks on achromatic dynamic Glass pattern stimuli. Coloured instructions, target frames and fixation points were used to attempt to bias performance to different task types. Based on previous literature, we hypothesised that red cues would improve performance in the (local) contrast detection task but would impede performance in the (global) form detection task.  A two-way, repeated measures, analysis of covariance (2×2 ANCOVA) with gender as a covariate, revealed no influence of colour on either task, F(1,29) = 0.289, p = 0.595, partial η (2) = 0.002. Additional analysis revealed no significant differences in only the first attempts of the tasks or in the improvement in performance between trials. We conclude that motivational processes elicited by colour perception do not influence neuronal signal processing in the early visual system, in stark contrast to their putative effects on processing in higher areas.

Reasoning strategies with rational numbers revealed by eye tracking.

PubMed

Plummer, Patrick; DeWolf, Melissa; Bassok, Miriam; Gordon, Peter C; Holyoak, Keith J

2017-07-01

Recent research has begun to investigate the impact of different formats for rational numbers on the processes by which people make relational judgments about quantitative relations. DeWolf, Bassok, and Holyoak (Journal of Experimental Psychology: General, 144(1), 127-150, 2015) found that accuracy on a relation identification task was highest when fractions were presented with countable sets, whereas accuracy was relatively low for all conditions where decimals were presented. However, it is unclear what processing strategies underlie these disparities in accuracy. We report an experiment that used eye-tracking methods to externalize the strategies that are evoked by different types of rational numbers for different types of quantities (discrete vs. continuous). Results showed that eye-movement behavior during the task was jointly determined by image and number format. Discrete images elicited a counting strategy for both fractions and decimals, but this strategy led to higher accuracy only for fractions. Continuous images encouraged magnitude estimation and comparison, but to a greater degree for decimals than fractions. This strategy led to decreased accuracy for both number formats. By analyzing participants' eye movements when they viewed a relational context and made decisions, we were able to obtain an externalized representation of the strategic choices evoked by different ontological types of entities and different types of rational numbers. Our findings using eye-tracking measures enable us to go beyond previous studies based on accuracy data alone, demonstrating that quantitative properties of images and the different formats for rational numbers jointly influence strategies that generate eye-movement behavior.

Analyzing Global Components in Developmental Dyscalculia and Dyslexia.

PubMed

Filippo, Gloria Di; Zoccolotti, Pierluigi

2018-01-01

The study examined whether developmental deficits in reading and numerical skills could be expressed in terms of global factors by reference to the rate and amount (RAM) and difference engine (DEM) models. From a sample of 325 fifth grade children, we identified 5 children with dyslexia, 16 with dyscalculia, 7 with a "mixed pattern," and 49 control children. Children were asked to read aloud words presented individually that varied for frequency and length and to respond (either vocally or manually) to a series of simple number tasks (addition, subtraction, number reading, and number comparisons). Reaction times were measured. Results indicated that the deficit of children with dyscalculia and children with a mixed pattern on numerical tasks could be explained by a single global factor, similarly to the reading deficit shown by children with dyslexia. As predicted by the DEM, increases in task difficulty were accompanied by a corresponding increase in inter-individual variability for both the reading and numerical tasks. These relationships were constant across the four groups of children but differed in terms of slope and intercept on the x -axis, indicating that two different general rules underlie performance in reading and numerical skills. The study shows for the first time that, as previously shown for reading, also numerical performance can be explained with reference to a global factor. The advantage of this approach is that it takes into account the over-additivity effect, i.e., the presence of larger group differences in the case of more difficult conditions over and above the characteristics of the experimental conditions. It is concluded that reference to models such as the RAM and DEM can be useful in delineating the characteristics of the dyscalculic deficit as well as in the description of co-morbid disturbances, as in the case of dyslexia and dyscalculia.

Comparison of the Effects of Continuous Video Modeling, Video Prompting, and Video Modeling on Task Completion by Young Adults with Moderate Intellectual Disability

ERIC Educational Resources Information Center

Mechling, Linda C.; Ayres, Kevin M.; Bryant, Kathryn J.; Foster, Ashley L.

2014-01-01

This study compared the effects of three procedures (video prompting: VP, video modeling: VM, and continuous video modeling: CVM) on task completion by three high school students with moderate intellectual disability. The comparison was made across three sets of fundamentally different tasks (putting away household items in clusters of two items;…

Numerosity processing is context driven even in the subitizing range: An fMRI study

PubMed Central

Leibovich, Tali; Henik, Avishai; Salti, Moti

2015-01-01

Numerical judgments are involved in almost every aspect of our daily life. They are carried out so efficiently that they are often considered to be automatic and innate. However, numerosity of non-symbolic stimuli is highly correlated with its continuous properties (e.g., density, area), and so it is hard to determine whether numerosity and continuous properties rely on the same mechanism. Here we examined the behavioral and neuronal mechanisms underlying such judgments. We scanned subjects' hemodynamic responses to a numerosity comparison task and to a surface area comparison task. In these tasks, numerical and continuous magnitudes could be either congruent or incongruent. Behaviorally, an interaction between the order of the tasks and the relevant dimension modulated the congruency effects. Continuous magnitudes always interfered with numerosity comparison. Numerosity, on the other hand, interfered with the surface area comparison only when participants began with the numerosity task. Hemodynamic activity showed that context (induced by task order) determined the neuronal pathways in which the dimensions were processed. Starting with the numerosity task led to enhanced activity in the right hemisphere, while starting with the continuous task led to enhanced left hemisphere activity. Continuous magnitudes processing relied on activation of the frontal eye field and the post-central gyrus. Processing of numerosities, on the other hand, relied on deactivation of these areas, suggesting active suppression of the continuous dimension. Accordingly, we suggest that numerosities, even in the subitizing range, are not always processed automatically; their processing depends on context and task demands. PMID:26297625

Can Dyscalculics Estimate the Results of Arithmetic Problems?

PubMed

Ganor-Stern, Dana

2017-01-01

The present study is the first to examine the computation estimation skills of dyscalculics versus controls using the estimation comparison task. In this task, participants judged whether an estimated answer to a multidigit multiplication problem was larger or smaller than a given reference number. While dyscalculics were less accurate than controls, their performance was well above chance level. The performance of controls but not of those with developmental dyscalculia (DD) improved consistently for smaller problem sizes. The performance of both groups was superior when the reference number was smaller (vs. larger) than the exact answer and when it was far (vs. close) from it, both of which are considered to be the markers of the approximate number system (ANS). Strategy analysis distinguished between an approximated calculation strategy and a sense of magnitude strategy, which does not involve any calculation but relies entirely on the ANS. Dyscalculics used the latter more often than controls. The present results suggest that there is little, if any, impairment in the ANS of adults with DD and that their main deficiency is with performing operations on magnitudes rather than with the representations of the magnitudes themselves. © Hammill Institute on Disabilities 2015.

Set size influences the relationship between ANS acuity and math performance: a result of different strategies?

PubMed

Dietrich, Julia Felicitas; Nuerk, Hans-Christoph; Klein, Elise; Moeller, Korbinian; Huber, Stefan

2017-08-29

Previous research has proposed that the approximate number system (ANS) constitutes a building block for later mathematical abilities. Therefore, numerous studies investigated the relationship between ANS acuity and mathematical performance, but results are inconsistent. Properties of the experimental design have been discussed as a potential explanation of these inconsistencies. In the present study, we investigated the influence of set size and presentation duration on the association between non-symbolic magnitude comparison and math performance. Moreover, we focused on strategies reported as an explanation for these inconsistencies. In particular, we employed a non-symbolic magnitude comparison task and asked participants how they solved the task. We observed that set size was a significant moderator of the relationship between non-symbolic magnitude comparison and math performance, whereas presentation duration of the stimuli did not moderate this relationship. This supports the notion that specific design characteristics contribute to the inconsistent results. Moreover, participants reported different strategies including numerosity-based, visual, counting, calculation-based, and subitizing strategies. Frequencies of these strategies differed between different set sizes and presentation durations. However, we found no specific strategy, which alone predicted arithmetic performance, but when considering the frequency of all reported strategies, arithmetic performance could be predicted. Visual strategies made the largest contribution to this prediction. To conclude, the present findings suggest that different design characteristics contribute to the inconsistent findings regarding the relationship between non-symbolic magnitude comparison and mathematical performance by inducing different strategies and additional processes.

Tracking the first two seconds: three stages of visual information processing?

PubMed

Jacob, Jane; Breitmeyer, Bruno G; Treviño, Melissa

2013-12-01

We compared visual priming and comparison tasks to assess information processing of a stimulus during the first 2 s after its onset. In both tasks, a 13-ms prime was followed at varying SOAs by a 40-ms probe. In the priming task, observers identified the probe as rapidly and accurately as possible; in the comparison task, observers determined as rapidly and accurately as possible whether or not the probe and prime were identical. Priming effects attained a maximum at an SOA of 133 ms and then declined monotonically to zero by 700 ms, indicating reliance on relatively brief visuosensory (iconic) memory. In contrast, the comparison effects yielded a multiphasic function, showing a maximum at 0 ms followed by a minimum at 133 ms, followed in turn by a maximum at 240 ms and another minimum at 720 ms, and finally a third maximum at 1,200 ms before declining thereafter. The results indicate three stages of prime processing that we take to correspond to iconic visible persistence, iconic informational persistence, and visual working memory, with the first two used in the priming task and all three in the comparison task. These stages are related to stages presumed to underlie stimulus processing in other tasks, such as those giving rise to the attentional blink.

Abstract number and arithmetic in preschool children.

PubMed

Barth, Hilary; La Mont, Kristen; Lipton, Jennifer; Spelke, Elizabeth S

2005-09-27

Educated humans use language to express abstract number, applying the same number words to seven apples, whistles, or sins. Is language or education the source of numerical abstraction? Claims to the contrary must present evidence for numerical knowledge that applies to disparate entities, in people who have received no formal mathematics instruction and cannot express such knowledge in words. Here we show that preschool children can compare and add large sets of elements without counting, both within a single visual-spatial modality (arrays of dots) and across two modalities and formats (dot arrays and tone sequences). In two experiments, children viewed animations and either compared one visible array of dots to a second array or added two successive dot arrays and compared the sum to a third array. In further experiments, a dot array was replaced by a sequence of sounds, so that participants had to integrate quantity information presented aurally and visually. Children performed all tasks successfully, without resorting to guessing strategies or responding to continuous variables. Their accuracy varied with the ratio of the two quantities: a signature of large, approximate number representations in adult humans and animals. Addition was as accurate as comparison, even though children showed no relevant knowledge when presented with symbolic versions of the addition tasks. Abstract knowledge of number and addition therefore precedes, and may guide, language-based instruction in mathematics.

Age and gender dependent development of Theory of Mind in 6- to 8-years old children

PubMed Central

Calero, Cecilia I.; Salles, Alejo; Semelman, Mariano; Sigman, Mariano

2013-01-01

The ability to attribute different mental states to distinct individuals, or Theory of Mind (ToM), is widely believed to be developed mostly during preschool years. How different factors such as gender, number of siblings, or coarse personality traits affect this development is not entirely agreed upon. Here, we introduce a computerized version of the scaled ToM suite of tasks introduced by Wellman and Liu (2004), which allows us to meaningfully test ToM development on children 6 to 8-years old. We find that kids this age are still not entirely proficient in all ToM tasks, and continue to show a progression of performance with age. By testing this new age range, too, we are able to observe a significant advantage of girls over boys in ToM performance. Other factors such as number of siblings, birth order, and coarse personality traits show no significant relation with the ToM task results. Finally, we introduce a novel way to quantify the scaling property of the suite involving a sequence of set inclusions on one hand and a comparison between specially tailored sets of logistic models on the other. These measures confirm the validity of the scale in the 6- to 8-years old range. PMID:23785326

Age and gender dependent development of Theory of Mind in 6- to 8-years old children.

PubMed

Calero, Cecilia I; Salles, Alejo; Semelman, Mariano; Sigman, Mariano

2013-01-01

The ability to attribute different mental states to distinct individuals, or Theory of Mind (ToM), is widely believed to be developed mostly during preschool years. How different factors such as gender, number of siblings, or coarse personality traits affect this development is not entirely agreed upon. Here, we introduce a computerized version of the scaled ToM suite of tasks introduced by Wellman and Liu (2004), which allows us to meaningfully test ToM development on children 6 to 8-years old. We find that kids this age are still not entirely proficient in all ToM tasks, and continue to show a progression of performance with age. By testing this new age range, too, we are able to observe a significant advantage of girls over boys in ToM performance. Other factors such as number of siblings, birth order, and coarse personality traits show no significant relation with the ToM task results. Finally, we introduce a novel way to quantify the scaling property of the suite involving a sequence of set inclusions on one hand and a comparison between specially tailored sets of logistic models on the other. These measures confirm the validity of the scale in the 6- to 8-years old range.

A Binary Array Asynchronous Sorting Algorithm with Using Petri Nets

NASA Astrophysics Data System (ADS)

Voevoda, A. A.; Romannikov, D. O.

2017-01-01

Nowadays the tasks of computations speed-up and/or their optimization are actual. Among the approaches on how to solve these tasks, a method applying approaches of parallelization and asynchronization to a sorting algorithm is considered in the paper. The sorting methods are ones of elementary methods and they are used in a huge amount of different applications. In the paper, we offer a method of an array sorting that based on a division into a set of independent adjacent pairs of numbers and their parallel and asynchronous comparison. And this one distinguishes the offered method from the traditional sorting algorithms (like quick sorting, merge sorting, insertion sorting and others). The algorithm is implemented with the use of Petri nets, like the most suitable tool for an asynchronous systems description.

Comparison of the learning curves and frustration level in performing laparoscopic and robotic training skills by experts and novices.

PubMed

Passerotti, Carlo C; Franco, Felipe; Bissoli, Julio C C; Tiseo, Bruno; Oliveira, Caio M; Buchalla, Carlos A O; Inoue, Gustavo N C; Sencan, Arzu; Sencan, Aydin; do Pardo, Rogerio Ruscitto; Nguyen, Hiep T

2015-07-01

Robotic assistance may provide for distinct technical advantages over conventional laparoscopic technique. The goals of this study were (1) to objectively evaluate the difference in the learning curves by novice and expert surgeons in performing fundamental laparoscopic skills using conventional laparoscopic surgery (CLS) and robotic-assisted laparoscopic surgery (RALS) and (2) to evaluate the surgeons' frustration level in performing these tasks. Twelve experienced and 31 novices in laparoscopy were prospectively evaluated in performing three standardized laparoscopic tasks in five consecutive, weekly training sessions. Analysis of the learning curves was based on the magnitude, rate, and quickness in performance improvement. The participant's frustration and mood were also evaluated during and after every session. For the novice participants, RALS allowed for shorter time to task completion and greater accuracy. However, significant and rapid improvement in performance as measured by magnitude, rate, and quickness at each session was also seen with CLS. For the experienced surgeons, RALS only provided a slight improvement in performance. For all participants, the use of RALS was associated with less number of sessions in which they felt frustrated, less number of frustration episodes during a session, lower frustration score during and after the session, and higher good mood score. The advantages of RALS may be of most benefit when doing more complex tasks and by less experienced surgeons. RALS should not be used as a replacement for CLS but rather in specific situations in which it has the greatest advantages.

Can Dual Task Walking Improve in Parkinson's Disease After External Focus of Attention Exercise? A Single Blind Randomized Controlled Trial.

PubMed

Beck, Eric N; Intzandt, Brittany N; Almeida, Quincy J

2018-01-01

It may be possible to use attention-based exercise to decrease demands associated with walking in Parkinson's disease (PD), and thus improve dual task walking ability. For example, an external focus of attention (focusing on the effect of an action on the environment) may recruit automatic control processes degenerated in PD, whereas an internal focus (limb movement) may recruit conscious (nonautomatic) control processes. Thus, we aimed to investigate how externally and internally focused exercise influences dual task walking and symptom severity in PD. Forty-seven participants with PD were randomized to either an Externally (n = 24) or Internally (n = 23) focused group and completed 33 one-hour attention-based exercise sessions over 11 weeks. In addition, 16 participants were part of a control group. Before, after, and 8 weeks following the program (pre/post/washout), gait patterns were measured during single and dual task walking (digit-monitoring task, ie, walking while counting numbers announced by an audio-track), and symptom severity (UPDRS-III) was assessed ON and OFF dopamine replacement. Pairwise comparisons (95% confidence intervals [CIs]) and repeated-measures analyses of variance were conducted. Pre to post: Dual task step time decreased in the external group (Δ = 0.02 seconds, CI 0.01-0.04). Dual task step length (Δ = 2.3 cm, CI 0.86-3.75) and velocity (Δ = 4.5 cm/s, CI 0.59-8.48) decreased (became worse) in the internal group. UPDRS-III scores (ON and OFF) decreased (improved) in only the External group. Pre to washout: Dual task step time ( P = .005) and percentage in double support ( P = .014) significantly decreased (improved) in both exercise groups, although only the internal group increased error on the secondary counting task (ie, more errors monitoring numbers). UPDRS-III scores in both exercise groups significantly decreased ( P = .001). Since dual task walking improvements were found immediately, and 8 weeks after the cessation of an externally focused exercise program, we conclude that externally focused exercise may improve on functioning of automatic control networks in PD. Internally focused exercise hindered dual tasking ability. Overall, externally focused exercise led to greater rehabilitation benefits in dual tasking and motor symptoms compared with internally focused exercise.

Cultural differences in attention: Eye movement evidence from a comparative visual search task.

PubMed

Alotaibi, Albandri; Underwood, Geoffrey; Smith, Alastair D

2017-10-01

Individual differences in visual attention have been linked to thinking style: analytic thinking (common in individualistic cultures) is thought to promote attention to detail and focus on the most important part of a scene, whereas holistic thinking (common in collectivist cultures) promotes attention to the global structure of a scene and the relationship between its parts. However, this theory is primarily based on relatively simple judgement tasks. We compared groups from Great Britain (an individualist culture) and Saudi Arabia (a collectivist culture) on a more complex comparative visual search task, using simple natural scenes. A higher overall number of fixations for Saudi participants, along with longer search times, indicated less efficient search behaviour than British participants. Furthermore, intra-group comparisons of scan-path for Saudi participants revealed less similarity than within the British group. Together, these findings suggest that there is a positive relationship between an analytic cognitive style and controlled attention. Copyright © 2017 Elsevier Inc. All rights reserved.

Matching-to-sample by an echolocating dolphin (Tursiops truncatus).

PubMed

Roitblat, H L; Penner, R H; Nachtigall, P E

1990-01-01

An adult male dolphin was trained to perform a three-alternative delayed matching-to-sample task while wearing eyecups to occlude its vision. Sample and comparison stimuli consisted of a small and a large PVC plastic tube, a water-filled stainless steel sphere, and a solid aluminum cone. Stimuli were presented under water and the dolphin was allowed to identify the stimuli through echolocation. The echolocation clicks emitted by the dolphin to each sample and each comparison stimulus were recorded and analyzed. Over 48 sessions of testing, choice accuracy averaged 94.5% correct. This high level of accuracy was apparently achieved by varying the number of echolocation clicks emitted to various stimuli. Performance appeared to reflect a preexperimental stereotyped search pattern that dictated the order in which comparison items were examined and a complex sequential-sampling decision process. A model for the dolphin's decision-making processes is described.

The SNARC Effect in Number Memorization and Retrieval. What is the Impact of Congruency, Magnitude and the Exact Position of Numbers in Short-Term Memory Processing?

PubMed Central

Gut, Małgorzata; Staniszewski, Rafał

2016-01-01

Mental representations of numbers are spatially organized along a Mental Number Line (MNL). One widely proven manifestation of this relationship is the Spatial Numerical Association of Response Codes (SNARC) effect. It refers to the phenomenon of faster responses to numbers when there is congruency between the reaction side and the number position on the MNL . Although long-term memory is considered to house the MNL, short-term memory (STM) load may also modulate responses to numbers and the SN ARCRC effect. Our question, however, was not how STM content modulates the SNARC effect observed in responses to digits, but rather how the MNLNL representation affects the number retrieval from ST M. Each trial began with four digits presented horizontally in a spatial sequence (prime stimuli), which were then replaced by one of the priming digits as a single target. The task required participants to recall the exact location of the target. The SN ARCRC effect occurred only in the retrieval of left-sided digits, most likely because of the generally better processing of right-sided ones, as well as in reaction to digits presented more laterally. Moreover, memory processing was more efficient with low-magnitude numbers, which may suggest that they trigger attention shifting. We conclude that the MNL affects not only the responses to numbers obtained in typical SNARC-induction tasks, such as number detection, parity judgment or magnitude comparison, but also memorization and retrieval of them. Importantly, this effect seems to be dependent on the exact position of a digit in STM. PMID:28154615

The SNARC Effect in Number Memorization and Retrieval. What is the Impact of Congruency, Magnitude and the Exact Position of Numbers in Short-Term Memory Processing?

PubMed

Gut, Małgorzata; Staniszewski, Rafał

2016-01-01

Mental representations of numbers are spatially organized along a Mental Number Line (MNL). One widely proven manifestation of this relationship is the Spatial Numerical Association of Response Codes (SNARC) effect. It refers to the phenomenon of faster responses to numbers when there is congruency between the reaction side and the number position on the MNL . Although long-term memory is considered to house the MNL, short-term memory (STM) load may also modulate responses to numbers and the SN ARCRC effect. Our question, however, was not how STM content modulates the SNARC effect observed in responses to digits, but rather how the MNLNL representation affects the number retrieval from ST M. Each trial began with four digits presented horizontally in a spatial sequence (prime stimuli), which were then replaced by one of the priming digits as a single target. The task required participants to recall the exact location of the target. The SN ARCRC effect occurred only in the retrieval of left-sided digits, most likely because of the generally better processing of right-sided ones, as well as in reaction to digits presented more laterally. Moreover, memory processing was more efficient with low-magnitude numbers, which may suggest that they trigger attention shifting. We conclude that the MNL affects not only the responses to numbers obtained in typical SNARC-induction tasks, such as number detection, parity judgment or magnitude comparison, but also memorization and retrieval of them. Importantly, this effect seems to be dependent on the exact position of a digit in STM.

The influence of social cognition on ego disturbances in patients with schizophrenia.

PubMed

Schimansky, Jenny; Rössler, Wulf; Haker, Helene

2012-01-01

Subjects experiencing ego disturbances can be classified as a distinct subgroup of schizophrenia patients. These symptoms imply a disturbance in the ego-world boundary, which in turn implies aberrations in the perception, processing and understanding of social information. This paper provides a comparison of a group of schizophrenia patients and a group of healthy controls on a range of social-cognitive tasks. Furthermore, it analyzes the relationship between ego disturbances and social-cognitive as well as clinical variables in the schizophrenia subsample. Two groups - 40 schizophrenia patients and 39 healthy subjects - were compared. In the source monitoring task, subjects performed simple computer mouse movements and evaluated the partially manipulated visual feedback as either self- or other-generated. In a second step, participants indicated the confidence of their decision on a 4-point rating scale. In an emotion-recognition task, subjects had to identify 6 basic emotions in the prosody of spoken sentences. In the 'reading-the-mind-in-the-eyes' test, subjects had to infer mental states from pictures that depicted others' eyes. In an attribution task, subjects were presented with descriptions of social events and asked to attribute the cause of the event either to a person, an object or a situation. Additionally, all subjects were tested for cognitive functioning levels. The schizophrenia patient group performed significantly worse on all social-cognitive tasks than the healthy control group. Correlation analysis showed that ego disturbances were related to deficits in person attribution and lower levels of confidence in the source monitoring task. Also, ego disturbances were related to higher PANSS positive scores and a higher number of hospitalizations. Stepwise regression analysis revealed that social-cognitive variables explained 48.0% of the variance in the ego-disturbance score and represented the best predictors for ego disturbances. One particular clinical variable, namely the number of hospitalizations, additionally explained 13.8% of the variance. Our findings suggest that ego disturbances are related to deficits in the social-cognitive domain, and, to a lesser extent, to clinical variables such as the number of hospitalizations. Copyright © 2012 S. Karger AG, Basel.

Capuchin monkeys (Cebus apella) treat small and large numbers of items similarly during a relative quantity judgment task.

PubMed

Beran, Michael J; Parrish, Audrey E

2016-08-01

A key issue in understanding the evolutionary and developmental emergence of numerical cognition is to learn what mechanism(s) support perception and representation of quantitative information. Two such systems have been proposed, one for dealing with approximate representation of sets of items across an extended numerical range and another for highly precise representation of only small numbers of items. Evidence for the first system is abundant across species and in many tests with human adults and children, whereas the second system is primarily evident in research with children and in some tests with non-human animals. A recent paper (Choo & Franconeri, Psychonomic Bulletin & Review, 21, 93-99, 2014) with adult humans also reported "superprecise" representation of small sets of items in comparison to large sets of items, which would provide more support for the presence of a second system in human adults. We first presented capuchin monkeys with a test similar to that of Choo and Franconeri in which small or large sets with the same ratios had to be discriminated. We then presented the same monkeys with an expanded range of comparisons in the small number range (all comparisons of 1-9 items) and the large number range (all comparisons of 10-90 items in 10-item increments). Capuchin monkeys showed no increased precision for small over large sets in making these discriminations in either experiment. These data indicate a difference in the performance of monkeys to that of adult humans, and specifically that monkeys do not show improved discrimination performance for small sets relative to large sets when the relative numerical differences are held constant.

Cognitive inhibition in students with and without dyslexia and dyscalculia.

PubMed

Wang, Li-Chih; Tasi, Hung-Ju; Yang, Hsien-Ming

2012-01-01

The present study presents a comparison of the cognitive inhibition abilities of dyslexic, dyscalculic, and control students. The participants were 45 dyslexic students, 45 dyscalculic students, and 45 age-, gender-, and IQ-matched control students. The major evaluation tools included six cognitive inhibition tasks which were restructured during principal component analysis into three categories: graph inhibition, number inhibition, and word inhibition. Comparisons of the 3 groups of students revealed that in graph inhibition, dyscalculic students performed worst of the 3 groups, with dyslexic students also performing worse than control students in this category. For number inhibition, the control students' performances were equal to those of dyslexic students, with both groups performing better than dyscalculic students. For word inhibition, control students' performances were equal to those of dyscalculic students; both groups had shorter response times and lower incorrect rates than dyslexic students. These results suggest the complexity of the different cognitive inhibition abilities displayed by dyslexic, dyscalculic, and control students. However, some regular patterns occurred. Copyright © 2012 Elsevier Ltd. All rights reserved.

A Weight Comparison of Several Attitude Controls for Satellites

NASA Technical Reports Server (NTRS)

Adams, James J.; Chilton, Robert G.

1959-01-01

A brief theoretical study has been made for the purpose for estimating and comparing the weight of three different types of controls that can be used to change the attitude of a satellite. The three types of controls are jet reaction, inertia wheel, and a magnetic bar which interacts with the magnetic field of the earth. An idealized task which imposed severe requirements on the angular motion of the satellite was used as the basis for comparison. The results showed that a control for one axis can be devised which will weigh less than 1 percent of the total weight of the satellite. The inertia-wheel system offers weight-saving possibilities if a large number of cycles of operation are required, whereas the jet system would be preferred if a limited number of cycles are required. The magnetic-bar control requires such a large magnet that it is impractical for the example application but might be of value for supplying small trimming moments about certain axes.

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

PubMed

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

2011-02-01

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

Intentional and automatic numerical processing as predictors of mathematical abilities in primary school children

PubMed Central

Pina, Violeta; Castillo, Alejandro; Cohen Kadosh, Roi; Fuentes, Luis J.

2015-01-01

Previous studies have suggested that numerical processing relates to mathematical performance, but it seems that such relationship is more evident for intentional than for automatic numerical processing. In the present study we assessed the relationship between the two types of numerical processing and specific mathematical abilities in a sample of 109 children in grades 1–6. Participants were tested in an ample range of mathematical tests and also performed both a numerical and a size comparison task. The results showed that numerical processing related to mathematical performance only when inhibitory control was involved in the comparison tasks. Concretely, we found that intentional numerical processing, as indexed by the numerical distance effect in the numerical comparison task, was related to mathematical reasoning skills only when the task-irrelevant dimension (the physical size) was incongruent; whereas automatic numerical processing, indexed by the congruency effect in the size comparison task, was related to mathematical calculation skills only when digits were separated by small distance. The observed double dissociation highlights the relevance of both intentional and automatic numerical processing in mathematical skills, but when inhibitory control is also involved. PMID:25873909

Spatial but not temporal numerosity thresholds correlate with formal math skills in children.

PubMed

Anobile, Giovanni; Arrighi, Roberto; Castaldi, Elisa; Grassi, Eleonora; Pedonese, Lara; Moscoso, Paula A M; Burr, David C

2018-03-01

Humans and other animals are able to make rough estimations of quantities using what has been termed the approximate number system (ANS). Much evidence suggests that sensitivity to numerosity correlates with symbolic math capacity, leading to the suggestion that the ANS may serve as a start-up tool to develop symbolic math. Many experiments have demonstrated that numerosity perception transcends the sensory modality of stimuli and their presentation format (sequential or simultaneous), but it remains an open question whether the relationship between numerosity and math generalizes over stimulus format and modality. Here we measured precision for estimating the numerosity of clouds of dots and sequences of flashes or clicks, as well as for paired comparisons of the numerosity of clouds of dots. Our results show that in children, formal math abilities correlate positively with sensitivity for estimation and paired-comparisons of the numerosity of visual arrays of dots. However, precision of numerosity estimation for sequences of flashes or sounds did not correlate with math, although sensitivities in all estimations tasks (for sequential or simultaneous stimuli) were strongly correlated with each other. In adults, we found no significant correlations between math scores and sensitivity to any of the psychophysical tasks. Taken together these results support the existence of a generalized number sense, and go on to demonstrate an intrinsic link between mathematics and perception of spatial, but not temporal numerosity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The effect of two different electronic health record user interfaces on intensive care provider task load, errors of cognition, and performance.

PubMed

Ahmed, Adil; Chandra, Subhash; Herasevich, Vitaly; Gajic, Ognjen; Pickering, Brian W

2011-07-01

The care of critically ill patients generates large quantities of data. Increasingly, these data are presented to the provider within an electronic medical record. The manner in which data are organized and presented can impact on the ability of users to synthesis that data into meaningful information. The objective of this study was to test the hypothesis that novel user interfaces, which prioritize the display of high-value data to providers within system-based packages, reduce task load, and result in fewer errors of cognition compared with established user interfaces that do not. Randomized crossover study. Academic tertiary referral center. Attending, resident and fellow critical care physicians. Novel health care record user interface. Subjects randomly assigned to either a standard electronic medical record or a novel user interface, were asked to perform a structured task. The task required the subjects to use the assigned electronic environment to review the medical record of an intensive care unit patient said to be actively bleeding for data that formed the basis of answers to clinical questions posed in the form of a structured questionnaire. The primary outcome was task load, measured using the paper version of the NASA-task load index. Secondary outcome measures included time to task completion, number of errors of cognition measured by comparison of subject to post hoc gold standard questionnaire responses, and the quantity of information presented to subjects by each environment. Twenty subjects completed the task on eight patients, resulting in 160 patient-provider encounters (80 in each group). The standard electronic medical record contained a much larger data volume with a median (interquartile range) number of data points per patient of 1008 (895-1183) compared with 102 (77-112) contained within the novel user interface. The median (interquartile range) NASA-task load index values were 38.8 (32-45) and 58 (45-65) for the novel user interface compared with the standard electronic medical record (p < .001). The median (interquartile range) times in seconds taken to complete the task for four consecutive patients were 93 (57-132), 60 (48-71), 68 (48-80), and 54 (42-64) for the novel user interface compared with 145 (109-201), 125 (113-162), 129 (100-145), and 112 (92-123) for the standard interface (p < .0001), respectively. The median (interquartile range) number of errors per provider was 0.5 (0-1) and two (0.25-3) for the novel user interface and standard electronic medical record interface, respectively (p = .007). A novel user interface was designed based on the information needs of intensive care unit providers with a specific goal of development being the reduction of task load and errors of cognition associated with filtering, extracting, and using medical data contained within a comprehensive electronic medical record. The results of this simulated clinical experiment suggest that the configuration of the intensive care unit user interface contributes significantly to the task load, time to task completion, and number of errors of cognition associated with the identification, and subsequent use, of relevant patient data. Task-specific user interfaces, developed from an understanding of provider information requirements, offer advantages over interfaces currently available within a standard electronic medical record.

Count on dopamine: influences of COMT polymorphisms on numerical cognition

PubMed Central

Júlio-Costa, Annelise; Antunes, Andressa M.; Lopes-Silva, Júlia B.; Moreira, Bárbara C.; Vianna, Gabrielle S.; Wood, Guilherme; Carvalho, Maria R. S.; Haase, Vitor G.

2013-01-01

Catechol-O-methyltransferase (COMT) is an enzyme that is particularly important for the metabolism of dopamine. Functional polymorphisms of COMT have been implicated in working memory and numerical cognition. This is an exploratory study that aims at investigating associations between COMT polymorphisms, working memory, and numerical cognition. Elementary school children from 2th to 6th grades were divided into two groups according to their COMT val158met polymorphism [homozygous for valine allele (n = 61) vs. heterozygous plus methionine homozygous children or met+ group (n = 94)]. Both groups were matched for age and intelligence. Working memory was assessed through digit span and Corsi blocks. Symbolic numerical processing was assessed through transcoding and single-digit word problem tasks. Non-symbolic magnitude comparison and estimation tasks were used to assess number sense. Between-group differences were found in symbolic and non-symbolic numerical tasks, but not in working memory tasks. Children in the met+ group showed better performance in all numerical tasks while val homozygous children presented slower development of non-symbolic magnitude representations. These results suggest COMT-related dopaminergic modulation may be related not only to working memory, as found in previous studies, but also to the development of magnitude processing and magnitude representations. PMID:23966969

Task complexity modifies the search strategy of rats.

PubMed

Ruprecht, Chad M; Taylor, C Drew; Wolf, Joshua E; Leising, Kenneth J

2014-01-01

Human and non-human animals exhibit a variety of response strategies (e.g., place responding) when searching for a familiar place or evading predators. We still know little about the conditions that support the use of each strategy. We trained rats to locate a hidden food reward in a small-scale spatial search task. The complexity of the search task was manipulated by reducing the number of search locations (25, 4, and 2) within an open-field apparatus and by comparison to a path-based apparatus (plus-maze). After rats were trained to reliably locate the hidden food, each apparatus was shifted to gauge whether rats were searching at the location of the goal relative to extramaze cues (i.e., place responding), or searching in the direction of the goal relative to a combination of intramaze and extramaze cues (i.e.,directional responding). The results indicate that the open field supported place responding when more than two response locations were present, whereas, the four-arm plus-maze supported strong directional responding. These results extend prior research into the role of task demands on search strategy, as well as support the use of the four-choice open field as an analog to the Morris water task for future studies targeting the neural underpinnings of place responding.

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

PubMed

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

2015-02-01

To evaluate, in a simulated suturing task, individual surgeons’ performance using three surgical approaches: open, laparoscopic and robot-assisted. subjects and methods: Six urological surgeons made an in vitro simulated vesico-urethral anastomosis. All surgeons performed the simulated suturing task using all three surgical approaches (open, laparoscopic and robot-assisted). The time taken to perform each task was recorded. Participants were evaluated for perceived discomfort using the self-reporting Borg scale. Errors made by surgeons were quantified by studying the video recording of the tasks. Anastomosis quality was quantified using scores for knot security, symmetry of suture, position of suture and apposition of anastomosis. The time taken to complete the task by the laparoscopic approach was on average 221 s, compared with 55 s for the open approach and 116 s for the robot-assisted approach (anova, P < 0.005). The number of errors and the level of self-reported discomfort were highest for the laparoscopic approach (anova, P < 0.005). Limitations of the present study include the small sample size and variation in prior surgical experience of the participants. In an in vitro model of anastomosis surgery, robot-assisted surgery combines the accuracy of open surgery while causing lesser surgeon discomfort than laparoscopy and maintaining minimal access.

Functional Magnetic Resonance Imaging of Semantic Memory as a Presymptomatic Biomarker of Alzheimer’s Disease Risk

PubMed Central

Sugarman, Michael A.; Woodard, John L.; Nielson, Kristy A.; Seidenberg, Michael; Smith, J. Carson; Durgerian, Sally; Rao, Stephen M.

2011-01-01

Extensive research efforts have been directed toward strategies for predicting risk of developing Alzheimer’s disease (AD) prior to the appearance of observable symptoms. Existing approaches for early detection of AD vary in terms of their efficacy, invasiveness, and ease of implementation. Several non-invasive magnetic resonance imaging strategies have been developed for predicting decline in cognitively healthy older adults. This review will survey a number of studies, beginning with the development of a famous name discrimination task used to identify neural regions that participate in semantic memory retrieval and to test predictions of several key theories of the role of the hippocampus in memory. This task has revealed medial temporal and neocortical contributions to recent and remote memory retrieval, and it has been used to demonstrate compensatory neural recruitment in older adults, apolipoprotein E ε4 carriers, and amnestic mild cognitive impairment patients. Recently, we have also found that the famous name discrimination task provides predictive value for forecasting episodic memory decline among asymptomatic older adults. Other studies investigating the predictive value of semantic memory tasks will also be presented. We suggest several advantages associated with the use of semantic processing tasks, particularly those based on person identification, in comparison to episodic memory tasks to study AD risk. Future directions for research and potential clinical uses of semantic memory paradigms are also discussed. PMID:21996618

Performance norms for a rhesus monkey neuropsychological testing battery: acquisition and long-term performance.

PubMed

Weed, M R; Taffe, M A; Polis, I; Roberts, A C; Robbins, T W; Koob, G F; Bloom, F E; Gold, L H

1999-10-25

A computerized behavioral battery based upon human neuropsychological tests (CANTAB, CeNeS, Cambridge, UK) has been developed to assess cognitive behaviors of rhesus monkeys. Monkeys reliably performed multiple tasks, providing long-term assessment of changes in a number of behaviors for a given animal. The overall goal of the test battery is to characterize changes in cognitive behaviors following central nervous system (CNS) manipulations. The battery addresses memory (delayed non-matching to sample, DNMS; spatial working memory, using a self-ordered spatial search task, SOSS), attention (intra-/extra-dimensional shift, ID/ED), motivation (progressive-ratio, PR), reaction time (RT) and motor coordination (bimanual task). As with human neuropsychological batteries, different tasks are thought to involve different neural substrates, and therefore performance profiles should assess function in particular brain regions. Monkeys were tested in transport cages, and responding on a touch sensitive computer monitor was maintained by food reinforcement. Parametric manipulations of several tasks demonstrated the sensitivity of performance to increases in task difficulty. Furthermore, the factors influencing difficulty for rhesus monkeys were the same as those shown to affect human performance. Data from this study represent performance of a population of healthy normal monkeys that will be used for comparison in subsequent studies of performance following CNS manipulations such as infection with simian immunodeficiency virus (NeuroAIDS) or drug administration.

Familiarity and Within-Person Facial Variability: The Importance of the Internal and External Features.

PubMed

Kramer, Robin S S; Manesi, Zoi; Towler, Alice; Reynolds, Michael G; Burton, A Mike

2018-01-01

As faces become familiar, we come to rely more on their internal features for recognition and matching tasks. Here, we assess whether this same pattern is also observed for a card sorting task. Participants sorted photos showing either the full face, only the internal features, or only the external features into multiple piles, one pile per identity. In Experiments 1 and 2, we showed the standard advantage for familiar faces-sorting was more accurate and showed very few errors in comparison with unfamiliar faces. However, for both familiar and unfamiliar faces, sorting was less accurate for external features and equivalent for internal and full faces. In Experiment 3, we asked whether external features can ever be used to make an accurate sort. Using familiar faces and instructions on the number of identities present, we nevertheless found worse performance for the external in comparison with the internal features, suggesting that less identity information was available in the former. Taken together, we show that full faces and internal features are similarly informative with regard to identity. In comparison, external features contain less identity information and produce worse card sorting performance. This research extends current thinking on the shift in focus, both in attention and importance, toward the internal features and away from the external features as familiarity with a face increases.

Perceptual Distortions in Pitch and Time Reveal Active Prediction and Support for an Auditory Pitch-Motion Hypothesis

PubMed Central

Henry, Molly J.; McAuley, J. Devin

2013-01-01

A number of accounts of human auditory perception assume that listeners use prior stimulus context to generate predictions about future stimulation. Here, we tested an auditory pitch-motion hypothesis that was developed from this perspective. Listeners judged either the time change (i.e., duration) or pitch change of a comparison frequency glide relative to a standard (referent) glide. Under a constant-velocity assumption, listeners were hypothesized to use the pitch velocity (Δf/Δt) of the standard glide to generate predictions about the pitch velocity of the comparison glide, leading to perceptual distortions along the to-be-judged dimension when the velocities of the two glides differed. These predictions were borne out in the pattern of relative points of subjective equality by a significant three-way interaction between the velocities of the two glides and task. In general, listeners’ judgments along the task-relevant dimension (pitch or time) were affected by expectations generated by the constant-velocity standard, but in an opposite manner for the two stimulus dimensions. When the comparison glide velocity was faster than the standard, listeners overestimated time change, but underestimated pitch change, whereas when the comparison glide velocity was slower than the standard, listeners underestimated time change, but overestimated pitch change. Perceptual distortions were least evident when the velocities of the standard and comparison glides were matched. Fits of an imputed velocity model further revealed increasingly larger distortions at faster velocities. The present findings provide support for the auditory pitch-motion hypothesis and add to a larger body of work revealing a role for active prediction in human auditory perception. PMID:23936462

Perceptual distortions in pitch and time reveal active prediction and support for an auditory pitch-motion hypothesis.

PubMed

Henry, Molly J; McAuley, J Devin

2013-01-01

A number of accounts of human auditory perception assume that listeners use prior stimulus context to generate predictions about future stimulation. Here, we tested an auditory pitch-motion hypothesis that was developed from this perspective. Listeners judged either the time change (i.e., duration) or pitch change of a comparison frequency glide relative to a standard (referent) glide. Under a constant-velocity assumption, listeners were hypothesized to use the pitch velocity (Δf/Δt) of the standard glide to generate predictions about the pitch velocity of the comparison glide, leading to perceptual distortions along the to-be-judged dimension when the velocities of the two glides differed. These predictions were borne out in the pattern of relative points of subjective equality by a significant three-way interaction between the velocities of the two glides and task. In general, listeners' judgments along the task-relevant dimension (pitch or time) were affected by expectations generated by the constant-velocity standard, but in an opposite manner for the two stimulus dimensions. When the comparison glide velocity was faster than the standard, listeners overestimated time change, but underestimated pitch change, whereas when the comparison glide velocity was slower than the standard, listeners underestimated time change, but overestimated pitch change. Perceptual distortions were least evident when the velocities of the standard and comparison glides were matched. Fits of an imputed velocity model further revealed increasingly larger distortions at faster velocities. The present findings provide support for the auditory pitch-motion hypothesis and add to a larger body of work revealing a role for active prediction in human auditory perception.

The distance effect in numerical memory-updating tasks.

PubMed

Lendínez, Cristina; Pelegrina, Santiago; Lechuga, Teresa

2011-05-01

Two experiments examined the role of numerical distance in updating numerical information in working memory. In the first experiment, participants had to memorize a new number only when it was smaller than a previously memorized number. In the second experiment, updating was based on an external signal, which removed the need to perform any numerical comparison. In both experiments, distance between the memorized number and the new one was manipulated. The results showed that smaller distances between the new and the old information led to shorter updating times. This graded facilitation suggests that the process by which information is substituted in the focus of attention involves maintaining the shared features between the new and the old number activated and selecting other new features to be activated. Thus, the updating cost may be related to amount of new features to be activated in the focus of attention.

Impact of High Mathematics Education on the Number Sense

PubMed Central

Castronovo, Julie; Göbel, Silke M.

2012-01-01

In adult number processing two mechanisms are commonly used: approximate estimation of quantity and exact calculation. While the former relies on the approximate number sense (ANS) which we share with animals and preverbal infants, the latter has been proposed to rely on an exact number system (ENS) which develops later in life following the acquisition of symbolic number knowledge. The current study investigated the influence of high level math education on the ANS and the ENS. Our results showed that the precision of non-symbolic quantity representation was not significantly altered by high level math education. However, performance in a symbolic number comparison task as well as the ability to map accurately between symbolic and non-symbolic quantities was significantly better the higher mathematics achievement. Our findings suggest that high level math education in adults shows little influence on their ANS, but it seems to be associated with a better anchored ENS and better mapping abilities between ENS and ANS. PMID:22558077

Impact of high mathematics education on the number sense.

PubMed

Castronovo, Julie; Göbel, Silke M

2012-01-01

In adult number processing two mechanisms are commonly used: approximate estimation of quantity and exact calculation. While the former relies on the approximate number sense (ANS) which we share with animals and preverbal infants, the latter has been proposed to rely on an exact number system (ENS) which develops later in life following the acquisition of symbolic number knowledge. The current study investigated the influence of high level math education on the ANS and the ENS. Our results showed that the precision of non-symbolic quantity representation was not significantly altered by high level math education. However, performance in a symbolic number comparison task as well as the ability to map accurately between symbolic and non-symbolic quantities was significantly better the higher mathematics achievement. Our findings suggest that high level math education in adults shows little influence on their ANS, but it seems to be associated with a better anchored ENS and better mapping abilities between ENS and ANS.

The underlying number-space mapping among kindergarteners and its relation with early numerical abilities.

PubMed

Chan, Winnie Wai Lan; Wong, Terry Tin-Yau

2016-08-01

People map numbers onto space. The well-replicated SNARC (spatial-numerical association of response codes) effect indicates that people have a left-sided bias when responding to small numbers and a right-sided bias when responding to large numbers. This study examined whether such spatial codes were tagged to the ordinal or magnitude information of numbers among kindergarteners and whether it was related to early numerical abilities. Based on the traditional magnitude judgment task, we developed two variant tasks-namely the month judgment task and dot judgment task-to elicit ordinal and magnitude processing of numbers, respectively. Results showed that kindergarteners oriented small numbers toward the left side and large numbers toward the right side when processing the ordinal information of numbers in the month judgment task but not when processing the magnitude information in the number judgment task and dot judgment task, suggesting that the left-to-right spatial bias was probably tagged to the ordinal but not magnitude property of numbers. Moreover, the strength of the SNARC effect was not related to early numerical abilities. These findings have important implications for the early spatial representation of numbers and its role in numerical performance among kindergarteners. Copyright © 2016 Elsevier Inc. All rights reserved.

Separating Automatic and Intentional Inhibitory Mechanisms of Attention in Adults with Attention-Deficit/Hyperactivity Disorder

PubMed Central

Roberts, Walter; Fillmore, Mark T.; Milich, Richard

2011-01-01

Researchers in the cognitive sciences recognize a fundamental distinction between automatic and intentional mechanisms of inhibitory control. The use of eye-tracking tasks to assess selective attention has led to a better understanding of this distinction in specific populations such as children with attention-deficit/hyperactivity disorder (ADHD). This study examined automatic and intentional inhibitory control mechanisms in adults with ADHD using a saccadic interference (SI) task and a delayed ocular response (DOR) task. Thirty adults with ADHD were compared to 27 comparison adults on measures of inhibitory control. The DOR task showed that adults with ADHD were less able than comparison adults to inhibit a reflexive saccade towards the sudden appearance of a stimulus in the periphery. However, SI task performance showed that the ADHD group did not differ significantly from the comparison group on a measure of automatic inhibitory control. These findings suggest a dissociation between automatic and intentional inhibitory deficits in adults with ADHD. PMID:21058752

Kindergartners’ Fluent Processing of Symbolic Numerical Magnitude is Predicted by Their Cardinal Knowledge and Implicit Understanding of Arithmetic Two Years Earlier

PubMed Central

Moore, Alex M.; vanMarle, Kristy; Geary, David C.

2016-01-01

Fluency in first graders’ processing of the magnitudes associated with Arabic numerals, collections of objects, and mixtures of objects and numerals predicts current and future mathematics achievement. The quantitative competencies that support the development of fluent processing of magnitude are not fully understood, however. At the beginning and end of preschool (M = 3 years, 9 months at first assessment; range 3 years, 3 months to 4years, 3 months), 112 (51 boys) children completed tasks measuring numeral recognition and comparison, acuity of the approximate number system, and knowledge of counting principles, cardinality, and implicit arithmetic, and completed a magnitude processing task (number sets test) in kindergarten. Use of Bayesian and linear regression techniques revealed that two measures of preschoolers’ cardinal knowledge and their competence at implicit arithmetic predicted later fluency of magnitude processing, controlling domain general factors, preliteracy skills, and parental education. The results help to narrow the search for the early foundation of children’s emerging competence with symbolic mathematics and provide direction for early interventions. PMID:27236038

Kindergartners' fluent processing of symbolic numerical magnitude is predicted by their cardinal knowledge and implicit understanding of arithmetic 2years earlier.

PubMed

Moore, Alex M; vanMarle, Kristy; Geary, David C

2016-10-01

Fluency in first graders' processing of the magnitudes associated with Arabic numerals, collections of objects, and mixtures of objects and numerals predicts current and future mathematics achievement. The quantitative competencies that support the development of fluent processing of magnitude, however, are not fully understood. At the beginning and end of preschool (M=3years 9months at first assessment, range=3years 3months to 4years 3months), 112 children (51 boys) completed tasks measuring numeral recognition and comparison, acuity of the approximate number system, and knowledge of counting principles, cardinality, and implicit arithmetic and also completed a magnitude processing task (number sets test) in kindergarten. Use of Bayesian and linear regression techniques revealed that two measures of preschoolers' cardinal knowledge and their competence at implicit arithmetic predicted later fluency of magnitude processing, controlling domain-general factors, preliteracy skills, and parental education. The results help to narrow the search for the early foundation of children's emerging competence with symbolic mathematics and provide direction for early interventions. Copyright © 2016 Elsevier Inc. All rights reserved.

Space Environmental Effects Knowledgebase

NASA Technical Reports Server (NTRS)

Wood, B. E.

2007-01-01

This report describes the results of an NRA funded program entitled Space Environmental Effects Knowledgebase that received funding through a NASA NRA (NRA8-31) and was monitored by personnel in the NASA Space Environmental Effects (SEE) Program. The NASA Project number was 02029. The Satellite Contamination and Materials Outgassing Knowledgebase (SCMOK) was created as a part of the earlier NRA8-20. One of the previous tasks and part of the previously developed Knowledgebase was to accumulate data from facilities using QCMs to measure the outgassing data for satellite materials. The main object of this current program was to increase the number of material outgassing datasets from 250 up to approximately 500. As a part of this effort, a round-robin series of materials outgassing measurements program was also executed that allowed comparison of the results for the same materials tested in 10 different test facilities. Other programs tasks included obtaining datasets or information packages for 1) optical effects of contaminants on optical surfaces, thermal radiators, and sensor systems and 2) space environmental effects data and incorporating these data into the already existing NASA/SEE Knowledgebase.

Quantification of crew workload imposed by communications-related tasks in commercial transport aircraft

NASA Technical Reports Server (NTRS)

Acton, W. H.; Crabtree, M. S.; Simons, J. C.; Gomer, F. E.; Eckel, J. S.

1983-01-01

Information theoretic analysis and subjective paired-comparison and task ranking techniques were employed in order to scale the workload of 20 communications-related tasks frequently performed by the captain and first officer of transport category aircraft. Tasks were drawn from taped conversations between aircraft and air traffic controllers (ATC). Twenty crewmembers performed subjective message comparisons and task rankings on the basis of workload. Information theoretic results indicated a broad range of task difficulty levels, and substantial differences between captain and first officer workload levels. Preliminary subjective data tended to corroborate these results. A hybrid scale reflecting the results of both the analytical and the subjective techniques is currently being developed. The findings will be used to select representative sets of communications for use in high fidelity simulation.

Counting ability in Down syndrome: The comprehension of the one-to-one correspondence principle and the role of receptive vocabulary.

PubMed

Abreu-Mendoza, Roberto A; Arias-Trejo, Natalia

2017-10-01

The authors investigated whether children with Down's syndrome (DS) who have not started to produce number words understand the one-to-one correspondence principle (Experiment 1), and they looked at the relationship between number word knowledge and receptive vocabulary (Experiment 2). Sixteen children with DS who did not recite the count list participated in Experiment 1, along with 2 comparison groups: 1 of 16 children with DS who recited up to 10, paired by chronological age, and another of 16 typically developing children paired by their ability to recite the list. The understanding of the principle was evaluated by a preferential looking task. Children saw 1 of 2 conditions. In the number condition, they heard number words and in the beep condition they heard computerized beeps. In both conditions, children saw videos depicting counting events that were principle-consistent or principle-inconsistent. Experiment 2 evaluated 25 children with DS using the Give-a-Number task and the Receptive Vocabulary subtest of the Wechsler Preschool and Primary Scale of Intelligence-III. In Experiment 1, children in the number condition preferred principle-consistent videos, independent of their ability to recite the count list. Experiment 2 showed a strong correlation between number word knowledge and receptive vocabulary scores, independent of chronological age. The results suggest that the difficulty of children with DS in acquiring counting ability might not reflect a lack of understanding of the one-to-one correspondence principle, but might instead be related to vocabulary development. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Novices in surgery are the target group of a virtual reality training laboratory.

PubMed

Hassan, Iyad; Maschuw, Katja; Rothmund, Matthias; Koller, Michael; Gerdes, Berthold

2006-01-01

This study aims to establish which physicians represent the suitable target group of a virtual training laboratory. Novices (48 physicians with fewer than 10 laparoscopic operations) and intermediate trainees (19 physicians who performed 30-50 laparoscopic operations) participated in this study. Each participant performed the basic module 'clip application' at the beginning and after a 1-hour short training course on the LapSim. The course consisted of the tasks coordination, lift and grasp, clip application, cutting with diathermy and fine dissection at increasing difficulty levels. The time taken to complete the tasks, number of errors, and economy of motion parameters (path length and angular path) were analyzed. Following training with the simulator, novices completed the task significantly faster (p = 0.001), demonstrated a greater economy of motion [path length (p = 0.04) and angular path (p = 0.01)]. In contrast, the intermediate trainees showed a reduction of their errors, but without reaching statistical significance. They showed no improvement in economy of motion and completed the task significantly slower (p = 0.03). Novices, in comparison to intermediate trainees, tend to benefit most during their first exposure to a laparoscopy simulator.

Testing visual short-term memory of pigeons (Columba livia) and a rhesus monkey (Macaca mulatta) with a location change detection task.

PubMed

Leising, Kenneth J; Elmore, L Caitlin; Rivera, Jacquelyne J; Magnotti, John F; Katz, Jeffrey S; Wright, Anthony A

2013-09-01

Change detection is commonly used to assess capacity (number of objects) of human visual short-term memory (VSTM). Comparisons with the performance of non-human animals completing similar tasks have shown similarities and differences in object-based VSTM, which is only one aspect ("what") of memory. Another important aspect of memory, which has received less attention, is spatial short-term memory for "where" an object is in space. In this article, we show for the first time that a monkey and pigeons can be accurately trained to identify location changes, much as humans do, in change detection tasks similar to those used to test object capacity of VSTM. The subject's task was to identify (touch/peck) an item that changed location across a brief delay. Both the monkey and pigeons showed transfer to delays longer than the training delay, to greater and smaller distance changes than in training, and to novel colors. These results are the first to demonstrate location-change detection in any non-human species and encourage comparative investigations into the nature of spatial and visual short-term memory.

Multi-Source Multi-Target Dictionary Learning for Prediction of Cognitive Decline.

PubMed

Zhang, Jie; Li, Qingyang; Caselli, Richard J; Thompson, Paul M; Ye, Jieping; Wang, Yalin

2017-06-01

Alzheimer's Disease (AD) is the most common type of dementia. Identifying correct biomarkers may determine pre-symptomatic AD subjects and enable early intervention. Recently, Multi-task sparse feature learning has been successfully applied to many computer vision and biomedical informatics researches. It aims to improve the generalization performance by exploiting the shared features among different tasks. However, most of the existing algorithms are formulated as a supervised learning scheme. Its drawback is with either insufficient feature numbers or missing label information. To address these challenges, we formulate an unsupervised framework for multi-task sparse feature learning based on a novel dictionary learning algorithm. To solve the unsupervised learning problem, we propose a two-stage Multi-Source Multi-Target Dictionary Learning (MMDL) algorithm. In stage 1, we propose a multi-source dictionary learning method to utilize the common and individual sparse features in different time slots. In stage 2, supported by a rigorous theoretical analysis, we develop a multi-task learning method to solve the missing label problem. Empirical studies on an N = 3970 longitudinal brain image data set, which involves 2 sources and 5 targets, demonstrate the improved prediction accuracy and speed efficiency of MMDL in comparison with other state-of-the-art algorithms.

Conflict resolution in two-digit number processing: evidence of an inhibitory mechanism.

PubMed

Macizo, Pedro

2017-01-01

We investigated the mechanism involved in conflict resolution when individuals processed two-digit numbers. Participants performed a comparison task in blocks of two trials. In the first trial, between-decade two-digit numbers were used in a compatible condition where the decade and the unit of one number were larger than those of the other number (i.e., 21-73) and an incompatible condition where the decade of one number was larger but the unit was smaller than those of the other number (i.e., 61-53). In the second trial, within-decade two-digit numbers were presented in a related condition where the numbers contained the units presented previously (i.e., 41-43) and an unrelated condition with units that did not appear before (i.e., 48-49). In the first trial, participants responded more slowly in incompatible trials relative to compatible trials. In the second trial, participants were slower in the related condition relative to unrelated trials only after incompatible trials. These results suggest that participants experienced conflict in the incompatible condition of first trial and that they inhibited irrelevant units to resolve conflict.

Inhibitory control and visuo-spatial reversibility in Piaget's seminal number conservation task: a high-density ERP study

PubMed Central

Borst, Grégoire; Simon, Grégory; Vidal, Julie; Houdé, Olivier

2013-01-01

The present high-density event-related potential (ERP) study on 13 adults aimed to determine whether number conservation relies on the ability to inhibit the overlearned length-equals-number strategy and then imagine the shortening of the row that was lengthened. Participants performed the number-conservation task and, after the EEG session, the mental imagery task. In the number-conservation task, first two rows with the same number of tokens and the same length were presented on a computer screen (COV condition) and then, the tokens in one of the two rows were spread apart (INT condition). Participants were instructed to determine whether the two rows had an identical number of tokens. In the mental imagery task, two rows with different lengths but the same number of tokens were presented and participants were instructed to imagine the tokens in the longer row aligning with the tokens in the shorter row. In the number-conservation task, we found that the amplitudes of the centro-parietal N2 and fronto-central P3 were higher in the INT than in the COV conditions. In addition, the differences in response times between the two conditions were correlated with the differences in the amplitudes of the fronto-central P3. In light of previous results reported on the number-conservation task in adults, the present results suggest that inhibition might be necessary to succeed the number-conservation task in adults even when the transformation of the length of one of the row is displayed. Finally, we also reported correlations between the speed at which participants could imagine the shortening of one of the row in the mental imagery task, the speed at which participants could determine that the two rows had the same number of tokens after the tokens in one of the row were spread apart and the latency of the late positive parietal component in the number-conservation task. Therefore, performing the number-conservation task might involve mental transformation processes in adults. PMID:24409135

In Search of Circasemidian Rhythms

DTIC Science & Technology

2006-11-01

NUMBER James C. Miller, Ph.D 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7757P905 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION...circasemidian rhythmicity in task performance was attributed to the nature of task, itself. Future investigations should attempt to replicate our...circasemidian rhythmicity in task performance was attributed to the nature of task, itself. Future investigations should attempt to replicate our findings

Social comparison modulates reward-driven attentional capture.

PubMed

Jiao, Jun; Du, Feng; He, Xiaosong; Zhang, Kan

2015-10-01

It is well established that attention can be captured by task irrelevant and non-salient objects associated with value through reward learning. However, it is unknown whether social comparison influences reward-driven attentional capture. The present study created four social contexts to examine whether different social comparisons modulate the reward-driven capture of attention. The results showed that reward-driven attentional capture varied with different social comparison conditions. Most prominently, reward-driven attentional capture is dramatically reduced in the disadvantageous social comparison context, in which an individual is informed that the other participant is earning more monetary reward for performing the same task. These findings suggest that social comparison can affect the reward-driven capture of attention.

Sex-typed play in gender-disturbed children: a comparison to sibling and psychiatric controls.

PubMed

Zucker, K J; Doering, R W; Bradley, S J; Finegan, J K

1982-08-01

Gender-disturbed children (n = 14) were compared to their preadolescent siblings (n = 16) and psychiatric controls (n = 13) on a sex-typed free-play task previously shown to differentiate gender-disturbed boys from normal boys. On three separate trials totaling 20 minutes, the gender-disturbed children played for a significantly longer period of time with cross-sex toys and for a significantly shorter period of time with same-sex toys than did the two control groups. The gender-disturbed children also showed greater trial-to-trial consistency in their play preferences than the other two groups. The utility of this task in the assessment of childhood gender disturbance is discussed. In addition, the results are discussed in relation to a number of perspectives regarding both typical and atypical gender identity development in childhood.

Conditional associative memory for musical stimuli in nonmusicians: implications for absolute pitch.

PubMed

Bermudez, Patrick; Zatorre, Robert J

2005-08-24

A previous positron emission tomography (PET) study of musicians with and without absolute pitch put forth the hypothesis that the posterior dorsolateral prefrontal cortex is involved in the conditional associative aspect of the identification of a pitch. In the work presented here, we tested this hypothesis by training eight nonmusicians to associate each of four different complex musical sounds (triad chords) with an arbitrary number in a task designed to have limited analogy to absolute-pitch identification. Each subject under-went a functional magnetic resonance imaging scanning procedure both before and after training. Active condition (identification of chords)-control condition (amplitude-matched noise bursts) comparisons for the pretraining scan showed no significant activation maxima. The same comparison for the posttraining scan revealed significant peaks of activation in posterior dorsolateral prefrontal, ventrolateral prefrontal, and parietal areas. A conjunction analysis was performed to show that the posterior dorsolateral prefrontal activity in this study is similar to that observed in the aforementioned PET study. We conclude that the posterior dorsolateral prefrontal cortex is selectively involved in the conditional association aspect of our task, as it is in the attribution of a verbal label to a note by absolute-pitch musicians.

A componential model of human interaction with graphs: 1. Linear regression modeling

NASA Technical Reports Server (NTRS)

Gillan, Douglas J.; Lewis, Robert

1994-01-01

Task analyses served as the basis for developing the Mixed Arithmetic-Perceptual (MA-P) model, which proposes (1) that people interacting with common graphs to answer common questions apply a set of component processes-searching for indicators, encoding the value of indicators, performing arithmetic operations on the values, making spatial comparisons among indicators, and repsonding; and (2) that the type of graph and user's task determine the combination and order of the components applied (i.e., the processing steps). Two experiments investigated the prediction that response time will be linearly related to the number of processing steps according to the MA-P model. Subjects used line graphs, scatter plots, and stacked bar graphs to answer comparison questions and questions requiring arithmetic calculations. A one-parameter version of the model (with equal weights for all components) and a two-parameter version (with different weights for arithmetic and nonarithmetic processes) accounted for 76%-85% of individual subjects' variance in response time and 61%-68% of the variance taken across all subjects. The discussion addresses possible modifications in the MA-P model, alternative models, and design implications from the MA-P model.

Rapid target foraging with reach or gaze: The hand looks further ahead than the eye

PubMed Central

2017-01-01

Real-world tasks typically consist of a series of target-directed actions and often require choices about which targets to act on and in what order. Such choice behavior can be assessed from an optimal foraging perspective whereby target selection is shaped by a balance between rewards and costs. Here we evaluated such decision-making in a rapid movement foraging task. On a given trial, participants were presented with 15 targets of varying size and value and were instructed to harvest as much reward as possible by either moving a handle to the targets (hand task) or by briefly fixating them (eye task). The short trial duration enabled participants to harvest about half the targets, ensuring that total reward was due to choice behavior. We developed a probabilistic model to predict target-by-target harvesting choices that considered the rewards and movement-related costs (i.e., target distance and size) associated with the current target as well as future targets. In the hand task, in comparison to the eye task, target choice was more strongly influenced by movement-related costs and took into account a greater number of future targets, consistent with the greater costs associated with arm movement. In both tasks, participants exhibited near-optimal behaviour and in a constrained version of the hand task in which choices could only be based on target positions, participants consistently chose among the shortest movement paths. Our results demonstrate that people can rapidly and effectively integrate values and movement-related costs associated with current and future targets when sequentially harvesting targets. PMID:28683138

Validation of operant social motivation paradigms using BTBR T+tf/J and C57BL/6J inbred mouse strains

PubMed Central

Martin, Loren; Sample, Hannah; Gregg, Michael; Wood, Caleb

2014-01-01

Background As purported causal factors are identified for autism spectrum disorder (ASD), new assays are needed to better phenotype animal models designed to explore these factors. With recent evidence suggesting that deficits in social motivation are at the core of ASD behavior, the development of quantitative measures of social motivation is particularly important. The goal of our study was to develop and validate novel assays to quantitatively measure social motivation in mice. Methods In order to test the validity of our paradigms, we compared the BTBR strain, with documented social deficits, to the prosocial C57BL/6J strain. Two novel conditioning paradigms were developed that allowed the test mouse to control access to a social partner. In the social motivation task, the test mice lever pressed for a social reward. The reward contingency was set on a progressive ratio of reinforcement and the number of lever presses achieved in the final trial of a testing session (breakpoint) was used as an index of social motivation. In the valence comparison task, motivation for a food reward was compared to a social reward. We also explored activity, social affiliation, and preference for social novelty through a series of tasks using an ANY-Maze video-tracking system in an open-field arena. Results BTBR mice had significantly lower breakpoints in the social motivation paradigm than C57BL/6J mice. However, the valence comparison task revealed that BTBR mice also made significantly fewer lever presses for a food reward. Conclusions The results of the conditioning paradigms suggest that the BTBR strain has an overall deficit in motivated behavior. Furthermore, the results of the open-field observations may suggest that social differences in the BTBR strain are anxiety induced. PMID:25328850

Validation of operant social motivation paradigms using BTBR T+tf/J and C57BL/6J inbred mouse strains.

PubMed

Martin, Loren; Sample, Hannah; Gregg, Michael; Wood, Caleb

2014-09-01

As purported causal factors are identified for autism spectrum disorder (ASD), new assays are needed to better phenotype animal models designed to explore these factors. With recent evidence suggesting that deficits in social motivation are at the core of ASD behavior, the development of quantitative measures of social motivation is particularly important. The goal of our study was to develop and validate novel assays to quantitatively measure social motivation in mice. In order to test the validity of our paradigms, we compared the BTBR strain, with documented social deficits, to the prosocial C57BL/6J strain. Two novel conditioning paradigms were developed that allowed the test mouse to control access to a social partner. In the social motivation task, the test mice lever pressed for a social reward. The reward contingency was set on a progressive ratio of reinforcement and the number of lever presses achieved in the final trial of a testing session (breakpoint) was used as an index of social motivation. In the valence comparison task, motivation for a food reward was compared to a social reward. We also explored activity, social affiliation, and preference for social novelty through a series of tasks using an ANY-Maze video-tracking system in an open-field arena. BTBR mice had significantly lower breakpoints in the social motivation paradigm than C57BL/6J mice. However, the valence comparison task revealed that BTBR mice also made significantly fewer lever presses for a food reward. The results of the conditioning paradigms suggest that the BTBR strain has an overall deficit in motivated behavior. Furthermore, the results of the open-field observations may suggest that social differences in the BTBR strain are anxiety induced.

Task-Driven Evaluation of Aggregation in Time Series Visualization

PubMed Central

Albers, Danielle; Correll, Michael; Gleicher, Michael

2014-01-01

Many visualization tasks require the viewer to make judgments about aggregate properties of data. Recent work has shown that viewers can perform such tasks effectively, for example to efficiently compare the maximums or means over ranges of data. However, this work also shows that such effectiveness depends on the designs of the displays. In this paper, we explore this relationship between aggregation task and visualization design to provide guidance on matching tasks with designs. We combine prior results from perceptual science and graphical perception to suggest a set of design variables that influence performance on various aggregate comparison tasks. We describe how choices in these variables can lead to designs that are matched to particular tasks. We use these variables to assess a set of eight different designs, predicting how they will support a set of six aggregate time series comparison tasks. A crowd-sourced evaluation confirms these predictions. These results not only provide evidence for how the specific visualizations support various tasks, but also suggest using the identified design variables as a tool for designing visualizations well suited for various types of tasks. PMID:25343147

A Comparison of the Compression Response of Thick (6.35mm) and Thin (1.60mm) Dry and Moisture Saturated AS4/3501-6 Laminates

DTIC Science & Technology

1990-10-01

of 1.27 mm/mm/min (0.05 in./in./min.) using a 60 kip Satec universal machine, with a spherically seated compression platen for alignment purposes. At...Task No. 6. AUTHOR(S) R3450SOS, ROOONOO, Work Karin Gipple Unit No. 2802-950 and 2844-220 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS( ES ) 8... ES ) 10. SPONSORING /MONITOR ING AGENCY REPORT NUMBER DTRC Materials Block, IR 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION /AVAILABILTY STATEMENT 12b

The Development of the Mental Representations of the Magnitude of Fractions

PubMed Central

Gabriel, Florence C.; Szucs, Denes; Content, Alain

2013-01-01

We investigated the development of the mental representation of the magnitude of fractions during the initial stages of fraction learning in grade 5, 6 and 7 children as well as in adults. We examined the activation of global fraction magnitude in a numerical comparison task and a matching task. There were global distance effects in the comparison task, but not in the matching task. This suggests that the activation of the global magnitude representation of fractions is not automatic in all tasks involving magnitude judgments. The slope of the global distance effect increased during early fraction learning and declined by adulthood, demonstrating that the development of the fraction global distance effect differs from that of the integer distance effect. PMID:24236169

Poor Performance on Serial Visual Tasks in Persons with Reading Disabilities: Impaired Working Memory?

ERIC Educational Resources Information Center

Ram-Tsur, Ronit; Faust, Miriam; Zivotofsky, Ari Z.

2008-01-01

The present study investigates the performance of persons with reading disabilities (PRD) on a variety of sequential visual-comparison tasks that have different working-memory requirements. In addition, mediating relationships between the sequential comparison process and attention and memory skills were looked for. Our findings suggest that PRD…

Learners' Uses of Two Types of Written Feedback on a L2 Writing Revision Task

ERIC Educational Resources Information Center

Sachs, Rebecca; Polio, Charlene

2007-01-01

This study examines the effectiveness of written error corrections versus reformulations of second language learners' writing as two means of improving learners' grammatical accuracy on a three-stage composition-comparison-revision task. Concurrent verbal protocols were employed during the comparison stage in order to study the learners' reported…

Unbounding the mental number line—new evidence on children's spatial representation of numbers

PubMed Central

Link, Tanja; Huber, Stefan; Nuerk, Hans-Christoph; Moeller, Korbinian

2014-01-01

Number line estimation (i.e., indicating the position of a given number on a physical line) is a standard assessment of children's spatial representation of number magnitude. Importantly, there is an ongoing debate on the question in how far the bounded task version with start and endpoint given (e.g., 0 and 100) might induce specific estimation strategies and thus may not allow for unbiased inferences on the underlying representation. Recently, a new unbounded version of the task was suggested with only the start point and a unit fixed (e.g., the distance from 0 to 1). In adults this task provided a less biased index of the spatial representation of number magnitude. Yet, so far there are no children data available for the unbounded number line estimation task. Therefore, we conducted a cross-sectional study on primary school children performing both, the bounded and the unbounded version of the task. We observed clear evidence for systematic strategic influences (i.e., the consideration of reference points) in the bounded number line estimation task for children older than grade two whereas there were no such indications for the unbounded version for any one of the age groups. In summary, the current data corroborate the unbounded number line estimation task to be a valuable tool for assessing children's spatial representation of number magnitude in a systematic and unbiased manner. Yet, similar results for the bounded and the unbounded version of the task for first- and second-graders may indicate that both versions of the task might assess the same underlying representation for relatively younger children—at least in number ranges familiar to the children assessed. This is of particular importance for inferences about the nature and development of children's magnitude representation. PMID:24478734

Representation of numerical magnitude in math-anxious individuals.

PubMed

Colomé, Àngels

2018-01-01

Larger distance effects in high math-anxious individuals (HMA) performing comparison tasks have previously been interpreted as indicating less precise magnitude representation in this population. A recent study by Dietrich, Huber, Moeller, and Klein limited the effects of math anxiety to symbolic comparison, in which they found larger distance effects for HMA, despite equivalent size effects. However, the question of whether distance effects in symbolic comparison reflect the properties of the magnitude representation or decisional processes is currently under debate. This study was designed to further explore the relation between math anxiety and magnitude representation through three different tasks. HMA and low math-anxious individuals (LMA) performed a non-symbolic comparison, in which no group differences were found. Furthermore, we did not replicate previous findings in an Arabic digit comparison, in which HMA individuals showed equivalent distance effects to their LMA peers. Lastly, there were no group differences in a counting Stroop task. Altogether, an explanation of math anxiety differences in terms of less precise magnitude representation is not supported.

Nano-Zirconium Tungstate Reinforced Liquid Crystalline Thermosetting Composites with Near Zero Thermal Expansion

DTIC Science & Technology

2015-06-25

5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Washington State University, Pullman...1234. 5c. PROGRAM ELEMENT NUMBER. Enter all program element numbers as they appear in the report, e.g. 61101A. 5d. PROJECT NUMBER. Enter all... project numbers as they appear in the report, e.g. 1F665702D1257; ILIR. 5e. TASK NUMBER. Enter all task numbers as they appear in the report

Comparison of School Counselors and School Social Workers: Performance of Tasks and Perceived Preparedness

ERIC Educational Resources Information Center

Feldman, Matthew

2010-01-01

This study compares the professional roles of school counselors and school social workers in terms of the frequency of performing various practice tasks, feelings of preparedness to perform various practice tasks, discrepancies between frequency of task performance and feelings of preparedness to perform said tasks, and factors that may affect…

VDA, a Method of Choosing a Better Algorithm with Fewer Validations

PubMed Central

Kluger, Yuval

2011-01-01

The multitude of bioinformatics algorithms designed for performing a particular computational task presents end-users with the problem of selecting the most appropriate computational tool for analyzing their biological data. The choice of the best available method is often based on expensive experimental validation of the results. We propose an approach to design validation sets for method comparison and performance assessment that are effective in terms of cost and discrimination power. Validation Discriminant Analysis (VDA) is a method for designing a minimal validation dataset to allow reliable comparisons between the performances of different algorithms. Implementation of our VDA approach achieves this reduction by selecting predictions that maximize the minimum Hamming distance between algorithmic predictions in the validation set. We show that VDA can be used to correctly rank algorithms according to their performances. These results are further supported by simulations and by realistic algorithmic comparisons in silico. VDA is a novel, cost-efficient method for minimizing the number of validation experiments necessary for reliable performance estimation and fair comparison between algorithms. Our VDA software is available at http://sourceforge.net/projects/klugerlab/files/VDA/ PMID:22046256

Number Sense and Mathematics: Which, When and How?

PubMed Central

2017-01-01

Individual differences in number sense correlate with mathematical ability and performance, although the presence and strength of this relationship differs across studies. Inconsistencies in the literature may stem from heterogeneity of number sense and mathematical ability constructs. Sample characteristics may also play a role as changes in the relationship between number sense and mathematics may differ across development and cultural contexts. In this study, 4,984 16-year-old students were assessed on estimation ability, one aspect of number sense. Estimation was measured using 2 different tasks: number line and dot-comparison. Using cognitive and achievement data previously collected from these students at ages 7, 9, 10, 12, and 14, the study explored for which of the measures and when in development these links are observed, and how strong these links are and how much these links are moderated by other cognitive abilities. The 2 number sense measures correlated modestly with each other (r = .22), but moderately with mathematics at age 16. Both measures were also associated with earlier mathematics; but this association was uneven across development and was moderated by other cognitive abilities. PMID:28758784

Neural Correlates of Encoding Predict Infants' Memory in the Paired-Comparison Procedure

ERIC Educational Resources Information Center

Snyder, Kelly A.

2010-01-01

The present study used event-related potentials (ERPs) to monitor infant brain activity during the initial encoding of a previously novel visual stimulus, and examined whether ERP measures of encoding predicted infants' subsequent performance on a visual memory task (i.e., the paired-comparison task). A late slow wave component of the ERP measured…

Self-Referenced Memory, Social Cognition, and Symptom Presentation in Autism

ERIC Educational Resources Information Center

Henderson, Heather A.; Zahka, Nicole E.; Kojkowski, Nicole M.; Inge, Anne P.; Schwartz, Caley B.; Hileman, Camilla M.; Coman, Drew C.; Mundy, Peter C.

2009-01-01

Background: We examined performance on a self-referenced memory (SRM) task for higher-functioning children with autism (HFA) and a matched comparison group. SRM performance was examined in relation to symptom severity and social cognitive tests of mentalizing. Method: Sixty-two children (31 HFA, 31 comparison; 8-16 years) completed a SRM task in…

Semantic and Phonological Task-Set Priming and Stimulus Processing Investigated Using Magnetoencephalography (MEG)

ERIC Educational Resources Information Center

McNab, F.; Rippon, G.; Hillebrand, A.; Singh, K. D.; Swithenby, S. J.

2007-01-01

In this study the neural substrates of semantic and phonological task priming and task performance were investigated using single word task-primes. Magnetoencephalography (MEG) data were analysed using Synthetic Aperture Magnetometry (SAM) to determine the spatiotemporal and spectral characteristics of cortical responses. Comparisons were made…

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

PubMed

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

2017-01-01

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

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

PubMed Central

Madni, Syed Hamid Hussain; Abd Latiff, Muhammad Shafie; Abdullahi, Mohammed; Usman, Mohammed Joda

2017-01-01

Cloud computing infrastructure is suitable for meeting computational needs of large task sizes. Optimal scheduling of tasks in cloud computing environment has been proved to be an NP-complete problem, hence the need for the application of heuristic methods. Several heuristic algorithms have been developed and used in addressing this problem, but choosing the appropriate algorithm for solving task assignment problem of a particular nature is difficult since the methods are developed under different assumptions. Therefore, six rule based heuristic algorithms are implemented and used to schedule autonomous tasks in homogeneous and heterogeneous environments with the aim of comparing their performance in terms of cost, degree of imbalance, makespan and throughput. First Come First Serve (FCFS), Minimum Completion Time (MCT), Minimum Execution Time (MET), Max-min, Min-min and Sufferage are the heuristic algorithms considered for the performance comparison and analysis of task scheduling in cloud computing. PMID:28467505

Analyzing Global Components in Developmental Dyscalculia and Dyslexia

PubMed Central

Filippo, Gloria Di; Zoccolotti, Pierluigi

2018-01-01

The study examined whether developmental deficits in reading and numerical skills could be expressed in terms of global factors by reference to the rate and amount (RAM) and difference engine (DEM) models. From a sample of 325 fifth grade children, we identified 5 children with dyslexia, 16 with dyscalculia, 7 with a “mixed pattern,” and 49 control children. Children were asked to read aloud words presented individually that varied for frequency and length and to respond (either vocally or manually) to a series of simple number tasks (addition, subtraction, number reading, and number comparisons). Reaction times were measured. Results indicated that the deficit of children with dyscalculia and children with a mixed pattern on numerical tasks could be explained by a single global factor, similarly to the reading deficit shown by children with dyslexia. As predicted by the DEM, increases in task difficulty were accompanied by a corresponding increase in inter-individual variability for both the reading and numerical tasks. These relationships were constant across the four groups of children but differed in terms of slope and intercept on the x-axis, indicating that two different general rules underlie performance in reading and numerical skills. The study shows for the first time that, as previously shown for reading, also numerical performance can be explained with reference to a global factor. The advantage of this approach is that it takes into account the over-additivity effect, i.e., the presence of larger group differences in the case of more difficult conditions over and above the characteristics of the experimental conditions. It is concluded that reference to models such as the RAM and DEM can be useful in delineating the characteristics of the dyscalculic deficit as well as in the description of co-morbid disturbances, as in the case of dyslexia and dyscalculia. PMID:29515490

Effects of Presentation Type and Visual Control in Numerosity Discrimination: Implications for Number Processing?

PubMed Central

Smets, Karolien; Moors, Pieter; Reynvoet, Bert

2016-01-01

Performance in a non-symbolic comparison task in which participants are asked to indicate the larger numerosity of two dot arrays, is assumed to be supported by the Approximate Number System (ANS). This system allows participants to judge numerosity independently from other visual cues. Supporting this idea, previous studies indicated that numerosity can be processed when visual cues are controlled for. Consequently, distinct types of visual cue control are assumed to be interchangeable. However, a previous study showed that the type of visual cue control affected performance using a simultaneous presentation of the stimuli in numerosity comparison. In the current study, we explored whether the influence of the type of visual cue control on performance disappeared when sequentially presenting each stimulus in numerosity comparison. While the influence of the applied type of visual cue control was significantly more evident in the simultaneous condition, sequentially presenting the stimuli did not completely exclude the influence of distinct types of visual cue control. Altogether, these results indicate that the implicit assumption that it is possible to compare performances across studies with a differential visual cue control is unwarranted and that the influence of the type of visual cue control partly depends on the presentation format of the stimuli. PMID:26869967

Functional magnetic resonance imaging of semantic memory as a presymptomatic biomarker of Alzheimer's disease risk.

PubMed

Sugarman, Michael A; Woodard, John L; Nielson, Kristy A; Seidenberg, Michael; Smith, J Carson; Durgerian, Sally; Rao, Stephen M

2012-03-01

Extensive research efforts have been directed toward strategies for predicting risk of developing Alzheimer's disease (AD) prior to the appearance of observable symptoms. Existing approaches for early detection of AD vary in terms of their efficacy, invasiveness, and ease of implementation. Several non-invasive magnetic resonance imaging strategies have been developed for predicting decline in cognitively healthy older adults. This review will survey a number of studies, beginning with the development of a famous name discrimination task used to identify neural regions that participate in semantic memory retrieval and to test predictions of several key theories of the role of the hippocampus in memory. This task has revealed medial temporal and neocortical contributions to recent and remote memory retrieval, and it has been used to demonstrate compensatory neural recruitment in older adults, apolipoprotein E ε4 carriers, and amnestic mild cognitive impairment patients. Recently, we have also found that the famous name discrimination task provides predictive value for forecasting episodic memory decline among asymptomatic older adults. Other studies investigating the predictive value of semantic memory tasks will also be presented. We suggest several advantages associated with the use of semantic processing tasks, particularly those based on person identification, in comparison to episodic memory tasks to study AD risk. Future directions for research and potential clinical uses of semantic memory paradigms are also discussed. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease. Copyright © 2011 Elsevier B.V. All rights reserved.

Introduction: Prediction of F-16XL Flight Flow Physics

NASA Technical Reports Server (NTRS)

Lamar, John E.

2009-01-01

This special section is the result of fruitful endeavors by an international group of researchers in industry, government laboratories and university-led efforts to improve the technology readiness level of their CFD solvers through comparisons with flight data collected on the F-16XL-1 aircraft at a variety of test conditions. These 1996 flight data were documented and detailed the flight-flow physics of this aircraft through surface tufts and pressures, boundary-layer rakes and skin-friction measurements. The flight project was called the Cranked Wing Aerodynamics Project (CAWAP), due to its leading-edge sweep crank (70 degrees inboard, 50 degrees outboard), and served as a basis for the International comparisons to be made, called CAWAPI. This highly focused effort was one of two vortical flow studies facilitated by the NATO Research and Technology Organization through its Applied Vehicle Panel with a title of Understanding and Modeling Vortical Flows to Improve the Technology Readiness Level for Military Aircraft. It was given a task group number of AVT-113 and had an official start date of Spring 2003. The companion part of this task group dealt with fundamentals of vortical flow from both an experimental and numerical perspective on an analytically describable 65 degree delta-wing model for which much surface pressure data had already been measured at NASA Langley Research Center at a variety of Mach and Reynolds numbers and is called the Vortex Flow Experiment - 2 (VFE-2). These two parts or facets helped one another in understanding the predictions and data that had been or were being collected.

Impaired Decision-Making in Adolescent Suicide Attempters

PubMed Central

Bridge, Jeffrey A.; McBee-Strayer, Sandra M.; Cannon, Elizabeth A.; Sheftall, Arielle H.; Reynolds, Brady; Campo, John V.; Pajer, Kathleen A.; Barbe, Rémy P.; Brent, David A.

2012-01-01

Objective Decision-making deficits have been linked to suicidal behavior in adults. However, it remains unclear whether impaired decision-making plays a role in the etiopathogenesis of youth suicidal behavior. The purpose of this study was to examine decision-making processes in adolescent suicide attempters and never-suicidal comparison subjects. Method Using the Iowa Gambling Task, the authors examined decision-making in 40 adolescent suicide attempters, ages 13–18, and 40 never-suicidal, demographically-matched psychiatric comparison subjects. Results Overall, suicide attempters performed significantly worse on the Iowa Gambling Task than comparison subjects. This difference in overall task performance between the groups persisted in an exact conditional logistic regression analysis that controlled for affective disorder, current psychotropic medication use, impulsivity, and hostility (adjusted odds ratio=0.96, 95% confidence interval=0.90–0.99, p<.05). A two-way repeated-measures analysis of variance revealed a significant group-by-block interaction, demonstrating that attempters failed to learn during the task, picking approximately the same proportion of disadvantageous cards in the first and final blocks of the task. In contrast, comparison subjects picked proportionately fewer cards from the disadvantageous decks as the task progressed. Within the attempter group, overall task performance did not correlate with any characteristic of the index attempt or with the personality dimensions of impulsivity, hostility, and emotional lability. Conclusions Similar to findings in adults, impaired decision-making is associated with suicidal behavior in adolescents. Longitudinal studies are needed to elucidate the temporal relationship between decision-making processes and suicidal behavior and help frame potential targets for early identification and preventive interventions to reduce youth suicide and suicidal behavior. PMID:22449645

Caloric restriction and spatial learning in old mice.

PubMed

Bellush, L L; Wright, A M; Walker, J P; Kopchick, J; Colvin, R A

1996-08-01

Spatial learning in old mice (19 or 24 months old), some of which had been calorically restricted beginning at 14 weeks of age, was compared to that of young mice, in two separate experiments using a Morris water maze. In the first experiment, only old mice reaching criterion performance on a cued learning task were tested in a subsequent spatial task. Thus, all old mice tested for spatial learning had achieved escape latencies equivalent to those of young controls. Despite equivalent swimming speeds, only about half the old mice in each diet group achieved criterion performance in the spatial task. In the second experiment, old and young mice all received the same number of training trials in a cued task and then in a spatial task. Immediately following spatial training, they were given a 60-s probe trial, with no platform in the pool. Both groups of old mice spent significantly less time in the quadrant where the platform had been and made significantly fewer direct crosses over the previous platform location than did the young control group. As in Experiment 1, calorie restriction failed to provide protection against aging-related deficits. However, in both experiments, some individual old mice evidenced performance in spatial learning indistinguishable from that of young controls. Separate comparisons of "age-impaired" and "age-unimpaired" old mice with young controls may facilitate the identification of neurobiological mechanisms underlying age-related cognitive decline.

TASK COMPLEXITY MODIFIES THE SEARCH STRATEGY OF RATS.

PubMed

Ruprecht, Chad M; Taylor, C Drew; Wolf, Joshua E; Leising, Kenneth J

2013-10-25

Human and non-human animals exhibit a variety of response strategies (e.g., place responding) when searching for a familiar place or evading predators. We still know little about the conditions that support the use of each strategy. We trained rats to locate a hidden food reward in a small-scale spatial search task. The complexity of the search task was manipulated by reducing the number of search locations (25, 4, and 2) within an open-field apparatus and by comparison to a path-based apparatus (plus maze). After rats were trained to reliably locate the hidden food, each apparatus was shifted to gauge whether rats were searching at the location of the goal relative to extramaze cues (i.e., place responding), or searching in the direction of the goal relative to a combination of intramaze and extramaze cues (i.e., directional responding). The results indicate that the open field supported place responding when more than two response locations were present, whereas, the four-arm plus-maze supported strong directional responding. These results extend prior research into the role of task demands on search strategy, as well as support the use of the four-choice open field as an analog to the Morris water task for future studies targeting the neural underpinnings of place responding. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimizing the number of steps in learning tasks for complex skills.

PubMed

Nadolski, Rob J; Kirschner, Paul A; van Merriënboer, Jeroen J G

2005-06-01

Carrying out whole tasks is often too difficult for novice learners attempting to acquire complex skills. The common solution is to split up the tasks into a number of smaller steps. The number of steps must be optimized for efficient and effective learning. The aim of the study is to investigate the relation between the number of steps provided to learners and the quality of their learning of complex skills. It is hypothesized that students receiving an optimized number of steps will learn better than those receiving either the whole task in only one step or those receiving a large number of steps. Participants were 35 sophomore law students studying at Dutch universities, mean age=22.8 years (SD=3.5), 63% were female. Participants were randomly assigned to 1 of 3 computer-delivered versions of a multimedia programme on how to prepare and carry out a law plea. The versions differed only in the number of learning steps provided. Videotaped plea-performance results were determined, various related learning measures were acquired and all computer actions were logged and analyzed. Participants exposed to an intermediate (i.e. optimized) number of steps outperformed all others on the compulsory learning task. No differences in performance on a transfer task were found. A high number of steps proved to be less efficient for carrying out the learning task. An intermediate number of steps is the most effective, proving that the number of steps can be optimized for improving learning.

Why rate when you could compare? Using the "EloChoice" package to assess pairwise comparisons of perceived physical strength.

PubMed

Clark, Andrew P; Howard, Kate L; Woods, Andy T; Penton-Voak, Ian S; Neumann, Christof

2018-01-01

We introduce "EloChoice", a package for R which uses Elo rating to assess pairwise comparisons between stimuli in order to measure perceived stimulus characteristics. To demonstrate the package and compare results from forced choice pairwise comparisons to those from more standard single stimulus rating tasks using Likert (or Likert-type) items, we investigated perceptions of physical strength from images of male bodies. The stimulus set comprised images of 82 men standing on a raised platform with minimal clothing. Strength-related anthropometrics and grip strength measurements were available for each man in the set. UK laboratory participants (Study 1) and US online participants (Study 2) viewed all images in both a Likert rating task, to collect mean Likert scores, and a pairwise comparison task, to calculate Elo, mean Elo (mElo), and Bradley-Terry scores. Within both studies, Likert, Elo and Bradley-Terry scores were closely correlated to mElo scores (all rs > 0.95), and all measures were correlated with stimulus grip strength (all rs > 0.38) and body size (all rs > 0.59). However, mElo scores were less variable than Elo scores and were hundreds of times quicker to compute than Bradley-Terry scores. Responses in pairwise comparison trials were 2/3 quicker than in Likert tasks, indicating that participants found pairwise comparisons to be easier. In addition, mElo scores generated from a data set with half the participants randomly excluded produced very comparable results to those produced with Likert scores from the full participant set, indicating that researchers require fewer participants when using pairwise comparisons.

An fMRI study of facial emotion processing in patients with schizophrenia.

PubMed

Gur, Raquel E; McGrath, Claire; Chan, Robin M; Schroeder, Lee; Turner, Travis; Turetsky, Bruce I; Kohler, Christian; Alsop, David; Maldjian, Joseph; Ragland, J Daniel; Gur, Ruben C

2002-12-01

Emotion processing deficits are notable in schizophrenia. The authors evaluated cerebral blood flow response in schizophrenia patients during facial emotion processing to test the hypothesis of diminished limbic activation related to emotional relevance of facial stimuli. Fourteen patients with schizophrenia and 14 matched comparison subjects viewed facial displays of happiness, sadness, anger, fear, and disgust as well as neutral faces. Functional magnetic resonance imaging was used to measure blood-oxygen-level-dependent signal changes as the subjects alternated between tasks of discriminating emotional valence (positive versus negative) and age (over 30 versus under 30) of the faces with an interleaved crosshair reference condition. The groups did not differ in performance on either task. For both tasks, healthy participants showed activation in the fusiform gyrus, occipital lobe, and inferior frontal cortex relative to the resting baseline condition. The increase was greater in the amygdala and hippocampus during the emotional valence discrimination task than during the age discrimination task. In the patients with schizophrenia, minimal focal response was observed for all tasks relative to the resting baseline condition. Contrasting patients and comparison subjects on the emotional valence discrimination task revealed voxels in the left amygdala and bilateral hippocampus in which the comparison subjects had significantly greater activation. Failure to activate limbic regions during emotional valence discrimination may explain emotion processing deficits in patients with schizophrenia. While the lack of limbic recruitment did not significantly impair simple valence discrimination performance in this clinically stable group, it may impact performance of more demanding tasks.

Cross-Cultural Study of Special Education Teachers' Perception of Iconicity of Graphic Symbols for Emotions

ERIC Educational Resources Information Center

Chae, Soo Jung

2011-01-01

This study was to investigate whether there are differences in perception of the symbols representing six emotions between the Korean and the American teachers. For an accurate comparison, two transparency tasks (Task 1-1 and Task 2) and one translucency task (Task 3) were used to investigate differences between Korean and American special…

Robotics/Automated Systems Task Analysis and Description of Required Job Competencies Report. Task Analysis and Description of Required Job Competencies of Robotics/Automated Systems Technicians.

ERIC Educational Resources Information Center

Hull, Daniel M.; Lovett, James E.

This task analysis report for the Robotics/Automated Systems Technician (RAST) curriculum project first provides a RAST job description. It then discusses the task analysis, including the identification of tasks, the grouping of tasks according to major areas of specialty, and the comparison of the competencies to existing or new courses to…

A comparison of SAR ATR performance with information theoretic predictions

NASA Astrophysics Data System (ADS)

Blacknell, David

2003-09-01

Performance assessment of automatic target detection and recognition algorithms for SAR systems (or indeed any other sensors) is essential if the military utility of the system / algorithm mix is to be quantified. This is a relatively straightforward task if extensive trials data from an existing system is used. However, a crucial requirement is to assess the potential performance of novel systems as a guide to procurement decisions. This task is no longer straightforward since a hypothetical system cannot provide experimental trials data. QinetiQ has previously developed a theoretical technique for classification algorithm performance assessment based on information theory. The purpose of the study presented here has been to validate this approach. To this end, experimental SAR imagery of targets has been collected using the QinetiQ Enhanced Surveillance Radar to allow algorithm performance assessments as a number of parameters are varied. In particular, performance comparisons can be made for (i) resolutions up to 0.1m, (ii) single channel versus polarimetric (iii) targets in the open versus targets in scrubland and (iv) use versus non-use of camouflage. The change in performance as these parameters are varied has been quantified from the experimental imagery whilst the information theoretic approach has been used to predict the expected variation of performance with parameter value. A comparison of these measured and predicted assessments has revealed the strengths and weaknesses of the theoretical technique as will be discussed in the paper.

A comparison of human performance in figural and navigational versions of the traveling salesman problem.

PubMed

Blaser, R E; Wilber, Julie

2013-11-01

Performance on a typical pen-and-paper (figural) version of the Traveling Salesman Problem was compared to performance on a room-sized navigational version of the same task. Nine configurations were designed to examine the use of the nearest-neighbor (NN), cluster approach, and convex-hull strategies. Performance decreased with an increasing number of nodes internal to the hull, and improved when the NN strategy produced the optimal path. There was no overall difference in performance between figural and navigational task modalities. However, there was an interaction between modality and configuration, with evidence that participants relied more heavily on the NN strategy in the figural condition. Our results suggest that participants employed similar, but not identical, strategies when solving figural and navigational versions of the problem. Surprisingly, there was no evidence that participants favored global strategies in the figural version and local strategies in the navigational version.

Narrative abilities, memory and attention in children with a specific language impairment.

PubMed

Duinmeijer, Iris; de Jong, Jan; Scheper, Annette

2012-01-01

While narrative tasks have proven to be valid measures for detecting language disorders, measuring communicative skills and predicting future academic performance, research into the comparability of different narrative tasks has shown that outcomes are dependent on the type of task used. Although many of the studies detecting task differences touch upon the fact that tasks place differential demands on cognitive abilities like auditory attention and memory, few studies have related specific narrative tasks to these cognitive abilities. Examining this relation is especially warranted for children with specific language impairment (SLI), who are characterized by language problems, but often have problems in other cognitive domains as well. In the current research, a comparison was made between a story retelling task (The Bus Story) and a story generation task (The Frog Story) in a group of children with SLI (n= 34) and a typically developing group (n= 38) from the same age range. In addition to the two narrative tasks, sustained auditory attention (TEA-Ch) and verbal working memory (WISC digit span and the Dutch version of the CVLT-C word list recall) were measured. Correlations were computed between the narrative, the memory and the attention scores. A group comparison showed that the children with SLI scored significantly worse than the typically developing children on several narrative measures as well as on sustained auditory attention and verbal working memory. A within-subjects comparison of the scores on the two narrative tasks showed a contrast between the tasks on several narrative measures. Furthermore, correlational analyses showed that, on the level of plot structure, the story generation task correlated with sustained auditory attention, while the story retelling task correlated with word list recall. Mean length of utterance (MLU) on the other hand correlated with digit span but not with sustained auditory attention. While children with SLI have problems with narratives in general, their performance is also dependent on the specific elicitation task used for research or diagnostics. Various narrative tasks generate different scores and are differentially correlated to cognitive skills like attention and memory, making the selection of a given task crucial in the clinical setting. © 2012 Royal College of Speech and Language Therapists.

Autonomic nervous system correlates to readiness state and negative outcome during visual discrimination tasks.

PubMed

Salvia, Emilie; Guillot, Aymeric; Collet, Christian

2012-05-01

Decision-making in daily activities require different levels of mental load depending on both objective task requirements and self-perception of task constraints. Such factors elicit strain that could influence information processing, decision-making, and forthcoming performance. This experiment aimed at studying how task difficulty, errors and unfair feedback may impact strain. Participants were requested to compare two polygons and to decide as quickly and accurately as possible whether these were identical or different. Task difficulty depended upon the number of polygon sides (from 12 to 21 sides) and their degree of similarity (different by 1, 2 or 3 sides). Reaction time (RT) and response accuracy were the dependent variables as well as electrodermal activity (EDA) and Instantaneous Heart Rate (IHR). Physiological variables from the autonomic nervous system were expected to evolve as a function of strain. As expected, we found that RT increased along with task difficulty. Similarly, the amplitude of IHR responses was affected by task difficulty. We recorded bradycardia during the 5s pre-stimulation period associated with correct responses, while wrong responses were associated with tachycardia. Bradycardia was thus a predictive index of performance related to the readiness to act when the participants focused on external cues. Processing identical polygons elicited longer electrodermal responses than those for different polygons. Indeed, the comparison of two different polygons ended as early as the difference was found. When similar, the participants were still looking for a difference and the issue was uncertain until the performance was displayed. Unfair information, i.e. wrong feedback associated with a good response, as well as response errors elicited larger and longer electrodermal responses. Autonomic nervous system activity was thus task-specific, and correlated to both cognitive and emotional processes. Copyright © 2012 Elsevier B.V. All rights reserved.

The development of a virtual reality training curriculum for colonoscopy.

PubMed

Sugden, Colin; Aggarwal, Rajesh; Banerjee, Amrita; Haycock, Adam; Thomas-Gibson, Siwan; Williams, Christopher B; Darzi, Ara

2012-07-01

The development of a structured virtual reality (VR) training curriculum for colonoscopy using high-fidelity simulation. Colonoscopy requires detailed knowledge and technical skill. Changes to working practices in recent times have reduced the availability of traditional training opportunities. Much might, therefore, be achieved by applying novel technologies such as VR simulation to colonoscopy. Scientifically developed device-specific curricula aim to maximize the yield of laboratory-based training by focusing on validated modules and linking progression to the attainment of benchmarked proficiency criteria. Fifty participants comprised of 30 novices (<10 colonoscopies), 10 intermediates (100 to 500 colonoscopies), and 10 experienced (>500 colonoscopies) colonoscopists were recruited to participate. Surrogates of proficiency, such as number of procedures undertaken, determined prospective allocation to 1 of 3 groups (novice, intermediate, and experienced). Construct validity and learning value (comparison between groups and within groups respectively) for each task and metric on the chosen simulator model determined suitability for inclusion in the curriculum. Eight tasks in possession of construct validity and significant learning curves were included in the curriculum: 3 abstract tasks, 4 part-procedural tasks, and 1 procedural task. The whole-procedure task was valid for 11 metrics including the following: "time taken to complete the task" (1238, 343, and 293 s; P < 0.001) and "insertion length with embedded tip" (23.8, 3.6, and 4.9 cm; P = 0.005). Learning curves consistently plateaued at or beyond the ninth attempt. Valid metrics were used to define benchmarks, derived from the performance of the experienced cohort, for each included task. A comprehensive, stratified, benchmarked, whole-procedure curriculum has been developed for a modern high-fidelity VR colonoscopy simulator.

Differences in the Efficiency of Pattern Encoding in Relation to Autistic-Like Traits: An Event-Related Potential Study

ERIC Educational Resources Information Center

Takahashi, Junichi; Yasunaga, Daichi; Gyoba, Jiro

2014-01-01

We examined the effects of complexity on the efficiency of pattern encoding in the general population differing on autism-spectrum quotient (AQ) scores. We compared brain activity (electroencephalography) during a same-different task for High and Low AQ groups. The task was composed of identical comparison and categorical comparison (CC)…

Independent vs. Integrated Writing Tasks: A Comparison of Task Representation

ERIC Educational Resources Information Center

Plakans, Lia

2010-01-01

As the field of second language writing embraces the authenticity and meaningfulness of connecting writing with other skills, language teachers and testers require greater understanding of how writers respond to as well as compose for integrated tasks. Research on integrated tasks is critical in highlighting how integration impacts students and…

Optimizing The Number Of Steps In Learning Tasks For Complex Skills

ERIC Educational Resources Information Center

Nadolski, Rob J.; Kirschner, Paul A.; van Merrienboer, Jeroen J.G.

2005-01-01

Background: Carrying out whole tasks is often too difficult for novice learners attempting to acquire complex skills. The common solution is to split up the tasks into a number of smaller steps. The number of steps must be optimized for efficient and effective learning. Aim: The aim of the study is to investigate the relation between the number of…

On the instability and constraints of the interaction between number representation and spatial attention in healthy humans: A concise review of the literature and new experimental evidence.

PubMed

Fattorini, E; Pinto, M; Merola, S; D'Onofrio, M; Doricchi, F

2016-01-01

The relationship between number and space representation is still one of the most debated topics in studies of mathematical cognition. Here we offer a concise review of two important behavioral effects that have pointed out the use of a spatially left-to-right oriented mental number line (MNL) in healthy participants: the SNARC effect and the attentional SNARC effect (Att-SNARC). Following a brief summary of seminal investigations on the introspective properties of the MNL, we review recent empirical evidence and theories on the functional origin of the SNARC effect, where upon left/right response choices faster reaction times are found for small numbers with left-side responses and for large numbers with right-side responses. Then we offer a summary of the studies that have investigated whether the mere perception of visual Arabic numbers presented at central fixation can engender spatially congruent lateral shifts of attention, ie, leftward for small numbers and rightward for large ones, ie, the Att-SNARC effect. Finally, we summarize four experiments that tested whether the Att-SNARC depends on an active rather than passive processing of centrally presented digit cues. In line with other recent studies, these experiment do not replicate the original Att-SNARC and show that the mere perception of Arabic numerals does not trigger automatic shifts of attention. These shifts are instead found when the task requires the explicit left/right spatial coding of digit cues, ie, Spatial Att-SNARC (Fattorini et al., 2015b). Nonetheless, the reliability of the Spatial Att-SNARC effect seems not as strong as that of conventional SNARC effects where left/right codes are mapped onto responses rather than directly mapped on digit cues. Comparing the magnitude of digits to a numerical reference, ie, "5," also produced a Magnitude Comparison Att-SNARC that was weaker than the spatial one. However, the reliability of this Magnitude Comparison Att-SNARC should be considered with caution because, like in a study by Zanolie and Pecher (2014), we recently failed to replicate this effect in a separate behavioral-event-related potentials study in preparation (Fattorini et al., 2015a). All together the results from the present series of experiments support the hypothesis that spatial coding is not an intrinsic part of number representation and that number-space interaction is determined by the use of stimulus- or response-related spatial codes in the task at hand. © 2016 Elsevier B.V. All rights reserved.

Muscle synergies in neuroscience and robotics: from input-space to task-space perspectives.

PubMed

Alessandro, Cristiano; Delis, Ioannis; Nori, Francesco; Panzeri, Stefano; Berret, Bastien

2013-01-01

In this paper we review the works related to muscle synergies that have been carried-out in neuroscience and control engineering. In particular, we refer to the hypothesis that the central nervous system (CNS) generates desired muscle contractions by combining a small number of predefined modules, called muscle synergies. We provide an overview of the methods that have been employed to test the validity of this scheme, and we show how the concept of muscle synergy has been generalized for the control of artificial agents. The comparison between these two lines of research, in particular their different goals and approaches, is instrumental to explain the computational implications of the hypothesized modular organization. Moreover, it clarifies the importance of assessing the functional role of muscle synergies: although these basic modules are defined at the level of muscle activations (input-space), they should result in the effective accomplishment of the desired task. This requirement is not always explicitly considered in experimental neuroscience, as muscle synergies are often estimated solely by analyzing recorded muscle activities. We suggest that synergy extraction methods should explicitly take into account task execution variables, thus moving from a perspective purely based on input-space to one grounded on task-space as well.

Multi-Source Multi-Target Dictionary Learning for Prediction of Cognitive Decline

PubMed Central

Zhang, Jie; Li, Qingyang; Caselli, Richard J.; Thompson, Paul M.; Ye, Jieping; Wang, Yalin

2017-01-01

Alzheimer’s Disease (AD) is the most common type of dementia. Identifying correct biomarkers may determine pre-symptomatic AD subjects and enable early intervention. Recently, Multi-task sparse feature learning has been successfully applied to many computer vision and biomedical informatics researches. It aims to improve the generalization performance by exploiting the shared features among different tasks. However, most of the existing algorithms are formulated as a supervised learning scheme. Its drawback is with either insufficient feature numbers or missing label information. To address these challenges, we formulate an unsupervised framework for multi-task sparse feature learning based on a novel dictionary learning algorithm. To solve the unsupervised learning problem, we propose a two-stage Multi-Source Multi-Target Dictionary Learning (MMDL) algorithm. In stage 1, we propose a multi-source dictionary learning method to utilize the common and individual sparse features in different time slots. In stage 2, supported by a rigorous theoretical analysis, we develop a multi-task learning method to solve the missing label problem. Empirical studies on an N = 3970 longitudinal brain image data set, which involves 2 sources and 5 targets, demonstrate the improved prediction accuracy and speed efficiency of MMDL in comparison with other state-of-the-art algorithms. PMID:28943731

Neural representations of magnitude for natural and rational numbers.

PubMed

DeWolf, Melissa; Chiang, Jeffrey N; Bassok, Miriam; Holyoak, Keith J; Monti, Martin M

2016-11-01

Humans have developed multiple symbolic representations for numbers, including natural numbers (positive integers) as well as rational numbers (both fractions and decimals). Despite a considerable body of behavioral and neuroimaging research, it is currently unknown whether different notations map onto a single, fully abstract, magnitude code, or whether separate representations exist for specific number types (e.g., natural versus rational) or number representations (e.g., base-10 versus fractions). We address this question by comparing brain metabolic response during a magnitude comparison task involving (on different trials) integers, decimals, and fractions. Univariate and multivariate analyses revealed that the strength and pattern of activation for fractions differed systematically, within the intraparietal sulcus, from that of both decimals and integers, while the latter two number representations appeared virtually indistinguishable. These results demonstrate that the two major notations formats for rational numbers, fractions and decimals, evoke distinct neural representations of magnitude, with decimals representations being more closely linked to those of integers than to those of magnitude-equivalent fractions. Our findings thus suggest that number representation (base-10 versus fractions) is an important organizational principle for the neural substrate underlying mathematical cognition. Copyright © 2016 Elsevier Inc. All rights reserved.

When Stroop helps Piaget: An inter-task positive priming paradigm in 9-year-old children.

PubMed

Linzarini, A; Houdé, O; Borst, G

2015-11-01

To determine whether inhibitory control is domain general or domain specific in school children, we asked 40 9-year-old children to perform an inter-task priming paradigm in which they responded to Stroop items on the primes and to Piaget number conservation items on the probes. The children were more efficient in the inhibition of a misleading "length-equals-number" heuristic in the number conservation task if they had successfully inhibited a previous prepotent reading response in the Stroop task. This study provides evidence that the inhibitory control ability of school children generalizes to distinct cognitive domains, that is, verbal for the Stroop task and logico-mathematical for Piaget's number conservation task. Copyright © 2015 Elsevier Inc. All rights reserved.

Automated Cloud Observation for Ground Telescope Optimization

NASA Astrophysics Data System (ADS)

Lane, B.; Jeffries, M. W., Jr.; Therien, W.; Nguyen, H.

As the number of man-made objects placed in space each year increases with advancements in commercial, academic and industry, the number of objects required to be detected, tracked, and characterized continues to grow at an exponential rate. Commercial companies, such as ExoAnalytic Solutions, have deployed ground based sensors to maintain track custody of these objects. For the ExoAnalytic Global Telescope Network (EGTN), observation of such objects are collected at the rate of over 10 million unique observations per month (as of September 2017). Currently, the EGTN does not optimally collect data on nights with significant cloud levels. However, a majority of these nights prove to be partially cloudy providing clear portions in the sky for EGTN sensors to observe. It proves useful for a telescope to utilize these clear areas to continue resident space object (RSO) observation. By dynamically updating the tasking with the varying cloud positions, the number of observations could potentially increase dramatically due to increased persistence, cadence, and revisit. This paper will discuss the recent algorithms being implemented within the EGTN, including the motivation, need, and general design. The use of automated image processing as well as various edge detection methods, including Canny, Sobel, and Marching Squares, on real-time large FOV images of the sky enhance the tasking and scheduling of a ground based telescope is discussed in Section 2. Implementations of these algorithms on single and expanding to multiple telescopes, will be explored. Results of applying these algorithms to the EGTN in real-time and comparison to non-optimized EGTN tasking is presented in Section 3. Finally, in Section 4 we explore future work in applying these throughout the EGTN as well as other optical telescopes.

Further dissociating the processes involved in recognition memory: an FMRI study.

PubMed

Henson, Richard N A; Hornberger, Michael; Rugg, Michael D

2005-07-01

Based on an event-related potential study by Rugg et al. [Dissociation of the neural correlates of implicit and explicit memory. Nature, 392, 595-598, 1998], we attempted to isolate the hemodynamic correlates of recollection, familiarity, and implicit memory within a single verbal recognition memory task using event-related fMRI. Words were randomly cued for either deep or shallow processing, and then intermixed with new words for yes/no recognition. The number of studied words was such that, whereas most were recognized ("hits"), an appreciable number of shallow-studied words were not ("misses"). Comparison of deep hits versus shallow hits at test revealed activations in regions including the left inferior parietal gyrus. Comparison of shallow hits versus shallow misses revealed activations in regions including the bilateral intraparietal sulci, the left posterior middle frontal gyrus, and the left frontopolar cortex. Comparison of hits versus correct rejections revealed a relative deactivation in an anterior left medial-temporal region (most likely the perirhinal cortex). Comparison of shallow misses versus correct rejections did not reveal response decreases in any regions expected on the basis of previous imaging studies of priming. Given these and previous data, we associate the left inferior parietal activation with recollection, the left anterior medial-temporal deactivation with familiarity, and the intraparietal and prefrontal responses with target detection. The absence of differences between shallow misses and correct rejections means that the hemodynamic correlates of implicit memory remain unclear.

Conceptual structure and the procedural affordances of rational numbers: relational reasoning with fractions and decimals.

PubMed

DeWolf, Melissa; Bassok, Miriam; Holyoak, Keith J

2015-02-01

The standard number system includes several distinct types of notations, which differ conceptually and afford different procedures. Among notations for rational numbers, the bipartite format of fractions (a/b) enables them to represent 2-dimensional relations between sets of discrete (i.e., countable) elements (e.g., red marbles/all marbles). In contrast, the format of decimals is inherently 1-dimensional, expressing a continuous-valued magnitude (i.e., proportion) but not a 2-dimensional relation between sets of countable elements. Experiment 1 showed that college students indeed view these 2-number notations as conceptually distinct. In a task that did not involve mathematical calculations, participants showed a strong preference to represent partitioned displays of discrete objects with fractions and partitioned displays of continuous masses with decimals. Experiment 2 provided evidence that people are better able to identify and evaluate ratio relationships using fractions than decimals, especially for discrete (or discretized) quantities. Experiments 3 and 4 found a similar pattern of performance for a more complex analogical reasoning task. When solving relational reasoning problems based on discrete or discretized quantities, fractions yielded greater accuracy than decimals; in contrast, when quantities were continuous, accuracy was lower for both symbolic notations. Whereas previous research has established that decimals are more effective than fractions in supporting magnitude comparisons, the present study reveals that fractions are relatively advantageous in supporting relational reasoning with discrete (or discretized) concepts. These findings provide an explanation for the effectiveness of natural frequency formats in supporting some types of reasoning, and have implications for teaching of rational numbers.

Dancing with the SNARC: Measuring spatial-numerical associations on a digital dance mat.

PubMed

Fischer, Ursula; Moeller, Korbinian; Class, Friderike; Huber, Stefan; Cress, Ulrike; Nuerk, Hans-Christoph

2016-12-01

According to the concept of embodied numerosity, bodily experiences influence the way in which we process numerical magnitude. The development of this influence could be anchored in the spatial ordering of numbers along a mental number line representation, which is measured by effects of spatial-numerical associations. The aim of this study was to investigate whether horizontally oriented full-body movement and visual presentation of a number line both contribute to spatial-numerical associations in children. We presented fourth-graders with 2 magnitude comparison tasks that differed in the relevance of magnitude information. In both tasks, we varied the amount of bodily movement in different response conditions (responding verbally, with a foot tap, or by jumping) and the visual presentation (items were presented with or without a number line). From the data, we calculated 2 spatial-numerical effects and expected to find the strongest effects if a full-body response was combined with a number line presentation. The 2 effects were differentially influenced by response modalities, but not presentation. The SNARC (= Spatial Numerical Association of Response Codes) effect was present in all conditions and was not influenced by our manipulations. In contrast, a new relative numerical congruity effect was influenced by the variations in responses in accordance with our hypotheses. The relative numerical congruity effect results suggest that responses involving bodily movement increase activation of spatial-numerical associations compared to verbal responses. These results are the first to demonstrate such an influence in a full-body approach in elementary schoolchildren. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A meta-heuristic method for solving scheduling problem: crow search algorithm

NASA Astrophysics Data System (ADS)

Adhi, Antono; Santosa, Budi; Siswanto, Nurhadi

2018-04-01

Scheduling is one of the most important processes in an industry both in manufacturingand services. The scheduling process is the process of selecting resources to perform an operation on tasks. Resources can be machines, peoples, tasks, jobs or operations.. The selection of optimum sequence of jobs from a permutation is an essential issue in every research in scheduling problem. Optimum sequence becomes optimum solution to resolve scheduling problem. Scheduling problem becomes NP-hard problem since the number of job in the sequence is more than normal number can be processed by exact algorithm. In order to obtain optimum results, it needs a method with capability to solve complex scheduling problems in an acceptable time. Meta-heuristic is a method usually used to solve scheduling problem. The recently published method called Crow Search Algorithm (CSA) is adopted in this research to solve scheduling problem. CSA is an evolutionary meta-heuristic method which is based on the behavior in flocks of crow. The calculation result of CSA for solving scheduling problem is compared with other algorithms. From the comparison, it is found that CSA has better performance in term of optimum solution and time calculation than other algorithms.

Further evidence for a spatial-numerical association in children before formal schooling.

PubMed

Ebersbach, Mirjam; Luwel, Koen; Verschaffel, Lieven

2014-01-01

Given the robust finding that number and space are associated systematically at least in school children and adults, it has been concluded that this association might be based on the frequent practice of reading or writing skills, which are usually consolidated by formal schooling. However, first studies contradict this assumption demonstrating that associations of "small" magnitudes with left space and of "large" magnitudes with right space exist already in preschoolers. The present study used a non-symbolic magnitude comparison task to examine whether kindergartners who have not yet been formally instructed in reading and writing show a SNARC effect, that is, whether they would respond more rapidly with the right hand to larger numbers and with the left hand to smaller numbers. This assumption was confirmed by the data. In view of further evidence for an association between number and space that evolves before children are proficient in reading and writing, the role of potential alternative culture-specific, individual, and universal foundations of this association is emphasized and discussed.

Hemispheric specialization in quantification processes.

PubMed

Pasini, M; Tessari, A

2001-01-01

Three experiments were carried out to study hemispheric specialization for subitizing (the rapid enumeration of small patterns) and counting (the serial quantification process based on some formal principles). The experiments consist of numerosity identification of dot patterns presented in one visual field, with a tachistoscopic technique, or eye movements monitored through glasses, and comparison between centrally presented dot patterns and lateralized tachistoscopically presented digits. Our experiments show left visual field advantage in the identification and comparison tasks in the subitizing range, whereas right visual field advantage has been found in the comparison task for the counting range.

Comparison of Identify-Friend-Foe and Blue-Force Tracking Decision Support for Combat Identification (Comparaison des Systemes d’aide a la Decision Identification ami ou Ennemi et Suivi des Forces Bleues pour l’Identification au Combat)

DTIC Science & Technology

2011-02-01

In the context of the CID task, sensitivity refers to subjects’ psychological discrimination between friends and foes, or their ability to...G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81-97...Wiley. 21. Macmillan, N. A., & Creelman , C. D. (1991). Detection theory: A user’s guide. Cambridge, UK: Cambridge University Press. DRDC Toronto

Stimulus Equivalence, Generalization, and Contextual Stimulus Control in Verbal Classes

PubMed Central

Sigurðardóttir, Zuilma Gabriela; Mackay, Harry A; Green, Gina

2012-01-01

Stimulus generalization and contextual control affect the development of equivalence classes. Experiment 1 demonstrated primary stimulus generalization from the members of trained equivalence classes. Adults were taught to match six spoken Icelandic nouns and corresponding printed words and pictures to one another in computerized three-choice matching-to-sample tasks. Tests confirmed that six equivalence classes had formed. Without further training, plural forms of the stimuli were presented in tests for all matching performances. All participants demonstrated virtually errorless performances. In Experiment 2, classifications of the nouns used in Experiment 1 were brought under contextual control. Three nouns were feminine and three were masculine. The match-to-sample training taught participants to select a comparison of the same number as the sample (i.e., singular or plural) in the presence of contextual stimulus A regardless of noun gender. Concurrently, in the presence of contextual stimulus B, participants were taught to select a comparison of the same gender as the sample (i.e., feminine or masculine), regardless of number. Generalization was assessed using a card-sorting test. All participants eventually sorted the cards correctly into gender and number stimulus classes. When printed words used in training were replaced by their picture equivalents, participants demonstrated almost errorless performances. PMID:22754102

Semantic Verbal Fluency in Children with and without Autism Spectrum Disorder: Relationship with Chronological Age and IQ

PubMed Central

Pastor-Cerezuela, Gemma; Fernández-Andrés, Maria-Inmaculada; Feo-Álvarez, Mireia; González-Sala, Francisco

2016-01-01

We administered a semantic verbal fluency (SVF) task to two groups of children (age range from 5 to 8): 47 diagnosed with Autism Spectrum Disorder (ASD Group) and 53 with typical development (Comparison Group), matched on gender, chronological age, and non-verbal IQ. Four specific indexes were calculated from the SVF task, reflecting the different underlying cognitive strategies used: clustering (component of generativity and lexical-semantic access), and switching (executive component, cognitive flexibility). First, we compared the performance of the two groups on the different SVF task indicators, with the ASD group scoring lower than the Comparison Group, although the difference was greater on switching than on clustering. Second, we analyzed the relationships between the different SVF measures and chronological age, verbal IQ and non-verbal IQ. While in the Comparison Group chronological age was the main predictor of performance on the SVF task, in the ASD Group verbal IQ was the best predictor. In the children with ASD, therefore, greater linguistic competence would be associated with better performance on the SVF task, which should be taken into account in speech therapies designed to achieve improvements in linguistic generativity and cognitive flexibility. PMID:27379002

Three DIBELS Tasks vs. Three Informal Reading/Spelling Tasks: A Comparison of Predictive Validity

ERIC Educational Resources Information Center

Morris, Darrell; Trathen, Woodrow; Perney, Jan; Gill, Tom; Schlagal, Robert; Ward, Devery; Frye, Elizabeth M.

2017-01-01

Within a developmental framework, this study compared the predictive validity of three DIBELS tasks (phoneme segmentation fluency [PSF], nonsense word fluency [NWF], and oral reading fluency [ORF]) with that of three alternative tasks drawn from the field of reading (phonemic spelling [phSPEL], word recognition-timed [WR-t], and graded passage…

Comparison of the Effects of Video Models with and without Verbal Cueing on Task Completion by Young Adults with Moderate Intellectual Disability

ERIC Educational Resources Information Center

Mechling, Linda C.; Collins, Terri S.

2012-01-01

This study compared the effects of video models with and without verbal cuing (voice over) on the completion of fine motor cooking related tasks by four young adults with moderate intellectual disability. The effects of the two modeling conditions were compared using an adapted alternating treatments design with an extended baseline, comparison,…

Why rate when you could compare? Using the “EloChoice” package to assess pairwise comparisons of perceived physical strength

PubMed Central

Howard, Kate L.; Woods, Andy T.; Penton-Voak, Ian S.; Neumann, Christof

2018-01-01

We introduce “EloChoice”, a package for R which uses Elo rating to assess pairwise comparisons between stimuli in order to measure perceived stimulus characteristics. To demonstrate the package and compare results from forced choice pairwise comparisons to those from more standard single stimulus rating tasks using Likert (or Likert-type) items, we investigated perceptions of physical strength from images of male bodies. The stimulus set comprised images of 82 men standing on a raised platform with minimal clothing. Strength-related anthropometrics and grip strength measurements were available for each man in the set. UK laboratory participants (Study 1) and US online participants (Study 2) viewed all images in both a Likert rating task, to collect mean Likert scores, and a pairwise comparison task, to calculate Elo, mean Elo (mElo), and Bradley-Terry scores. Within both studies, Likert, Elo and Bradley-Terry scores were closely correlated to mElo scores (all rs > 0.95), and all measures were correlated with stimulus grip strength (all rs > 0.38) and body size (all rs > 0.59). However, mElo scores were less variable than Elo scores and were hundreds of times quicker to compute than Bradley-Terry scores. Responses in pairwise comparison trials were 2/3 quicker than in Likert tasks, indicating that participants found pairwise comparisons to be easier. In addition, mElo scores generated from a data set with half the participants randomly excluded produced very comparable results to those produced with Likert scores from the full participant set, indicating that researchers require fewer participants when using pairwise comparisons. PMID:29293615

Preschool children use space, rather than counting, to infer the numerical magnitude of digits: Evidence for a spatial mapping principle.

PubMed

Sella, Francesco; Berteletti, Ilaria; Lucangeli, Daniela; Zorzi, Marco

2017-01-01

A milestone in numerical development is the acquisition of counting principles which allow children to exactly determine the numerosity of a given set. Moreover, a canonical left-to-right spatial layout for representing numbers also emerges during preschool. These foundational aspects of numerical competence have been extensively studied, but there is sparse knowledge about the interplay between the acquisition of the cardinality principle and spatial mapping of numbers in early numerical development. The present study investigated how these skills concurrently develop before formal schooling. Preschool children were classified according to their performance in Give-a-Number and Number-to-position tasks. Experiment 1 revealed three qualitatively different groups: (i) children who did not master the cardinality principle and lacked any consistent spatial mapping for digits, (ii) children who mastered the cardinality principle and yet failed in spatial mapping, and (iii) children who mastered the cardinality principle and displayed consistent spatial mapping. This suggests that mastery of the cardinality principle does not entail the emergence of spatial mapping. Experiment 2 confirmed the presence of these three developmental stages and investigated their relation with a digit comparison task. Crucially, only children who displayed a consistent spatial mapping of numbers showed the ability to compare digits by numerical magnitude. A congruent (i.e., numerically ordered) positioning of numbers onto a visual line as well as the concept that moving rightwards (in Western cultures) conveys an increase in numerical magnitude mark the mastery of a spatial mapping principle. Children seem to rely on this spatial organization to achieve a full understanding of the magnitude relations between digits. Copyright © 2016 Elsevier B.V. All rights reserved.

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

PubMed

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

2015-01-01

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

Diagnosing Developmental Dyscalculia on the Basis of Reliable Single Case FMRI Methods: Promises and Limitations

PubMed Central

Dinkel, Philipp Johannes; Willmes, Klaus; Krinzinger, Helga; Konrad, Kerstin; Koten Jr, Jan Willem

2013-01-01

FMRI-studies are mostly based on a group study approach, either analyzing one group or comparing multiple groups, or on approaches that correlate brain activation with clinically relevant criteria or behavioral measures. In this study we investigate the potential of fMRI-techniques focusing on individual differences in brain activation within a test-retest reliability context. We employ a single-case analysis approach, which contrasts dyscalculic children with a control group of typically developing children. In a second step, a support-vector machine analysis and cluster analysis techniques served to investigate similarities in multivariate brain activation patterns. Children were confronted with a non-symbolic number comparison and a non-symbolic exact calculation task during fMRI acquisition. Conventional second level group comparison analysis only showed small differences around the angular gyrus bilaterally and the left parieto-occipital sulcus. Analyses based on single-case statistical procedures revealed that developmental dyscalculia is characterized by individual differences predominantly in visual processing areas. Dyscalculic children seemed to compensate for relative under-activation in the primary visual cortex through an upregulation in higher visual areas. However, overlap in deviant activation was low for the dyscalculic children, indicating that developmental dyscalculia is a disorder characterized by heterogeneous brain activation differences. Using support vector machine analysis and cluster analysis, we tried to group dyscalculic and typically developing children according to brain activation. Fronto-parietal systems seem to qualify for a distinction between the two groups. However, this was only effective when reliable brain activations of both tasks were employed simultaneously. Results suggest that deficits in number representation in the visual-parietal cortex get compensated for through finger related aspects of number representation in fronto-parietal cortex. We conclude that dyscalculic children show large individual differences in brain activation patterns. Nonetheless, the majority of dyscalculic children can be differentiated from controls employing brain activation patterns when appropriate methods are used. PMID:24349547

Diagnosing developmental dyscalculia on the basis of reliable single case FMRI methods: promises and limitations.

PubMed

Dinkel, Philipp Johannes; Willmes, Klaus; Krinzinger, Helga; Konrad, Kerstin; Koten, Jan Willem

2013-01-01

FMRI-studies are mostly based on a group study approach, either analyzing one group or comparing multiple groups, or on approaches that correlate brain activation with clinically relevant criteria or behavioral measures. In this study we investigate the potential of fMRI-techniques focusing on individual differences in brain activation within a test-retest reliability context. We employ a single-case analysis approach, which contrasts dyscalculic children with a control group of typically developing children. In a second step, a support-vector machine analysis and cluster analysis techniques served to investigate similarities in multivariate brain activation patterns. Children were confronted with a non-symbolic number comparison and a non-symbolic exact calculation task during fMRI acquisition. Conventional second level group comparison analysis only showed small differences around the angular gyrus bilaterally and the left parieto-occipital sulcus. Analyses based on single-case statistical procedures revealed that developmental dyscalculia is characterized by individual differences predominantly in visual processing areas. Dyscalculic children seemed to compensate for relative under-activation in the primary visual cortex through an upregulation in higher visual areas. However, overlap in deviant activation was low for the dyscalculic children, indicating that developmental dyscalculia is a disorder characterized by heterogeneous brain activation differences. Using support vector machine analysis and cluster analysis, we tried to group dyscalculic and typically developing children according to brain activation. Fronto-parietal systems seem to qualify for a distinction between the two groups. However, this was only effective when reliable brain activations of both tasks were employed simultaneously. Results suggest that deficits in number representation in the visual-parietal cortex get compensated for through finger related aspects of number representation in fronto-parietal cortex. We conclude that dyscalculic children show large individual differences in brain activation patterns. Nonetheless, the majority of dyscalculic children can be differentiated from controls employing brain activation patterns when appropriate methods are used.

Student Off-Task Behavior in Computer-Based Learning in the Philippines: Comparison to Prior Research in the USA

ERIC Educational Resources Information Center

Rodrigo, Ma. Mercedes T.; Baker, Ryan S. J. D.; Rossi, Lisa

2013-01-01

Background: Off-task behavior can be defined as any behavior that does not involve the learning task or material, or where learning from the material is not the primary goal. One suggested path for understanding how to address off-task behavior is to study classrooms where off-task behavior is less common, particularly in Asia, in order to…

Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystem Concepts. Volume 1; Executive Summary

NASA Technical Reports Server (NTRS)

Levack, Daniel J. H.

2000-01-01

The Alternate Propulsion Subsystem Concepts contract had seven tasks defined that are reported under this contract deliverable. The tasks were: FAA Restart Study, J-2S Restart Study, Propulsion Database Development. SSME Upper Stage Use. CERs for Liquid Propellant Rocket Engines. Advanced Low Cost Engines, and Tripropellant Comparison Study. The two restart studies, F-1A and J-2S, generated program plans for restarting production of each engine. Special emphasis was placed on determining changes to individual parts due to obsolete materials, changes in OSHA and environmental concerns, new processes available, and any configuration changes to the engines. The Propulsion Database Development task developed a database structure and format which is easy to use and modify while also being comprehensive in the level of detail available. The database structure included extensive engine information and allows for parametric data generation for conceptual engine concepts. The SSME Upper Stage Use task examined the changes needed or desirable to use the SSME as an upper stage engine both in a second stage and in a translunar injection stage. The CERs for Liquid Engines task developed qualitative parametric cost estimating relationships at the engine and major subassembly level for estimating development and production costs of chemical propulsion liquid rocket engines. The Advanced Low Cost Engines task examined propulsion systems for SSTO applications including engine concept definition, mission analysis. trade studies. operating point selection, turbomachinery alternatives, life cycle cost, weight definition. and point design conceptual drawings and component design. The task concentrated on bipropellant engines, but also examined tripropellant engines. The Tripropellant Comparison Study task provided an unambiguous comparison among various tripropellant implementation approaches and cycle choices, and then compared them to similarly designed bipropellant engines in the SSTO mission This volume overviews each of the tasks giving its objectives, main results. and conclusions. More detailed Final Task Reports are available on each individual task.

An occupational exposure assessment for engineered nanoparticles used in semiconductor fabrication.

PubMed

Shepard, Michele Noble; Brenner, Sara

2014-03-01

Engineered nanoparticles of alumina, amorphous silica, and ceria are used in semiconductor device fabrication during wafer polishing steps referred to as 'chemical mechanical planarization' (CMP). Some metal oxide nanoparticles can impact the biological response of cells and organ systems and may cause adverse health effects; additional research is necessary to better understand potential risks from nanomaterial applications and occupational exposure scenarios. This study was conducted to assess potential airborne exposures to nanoparticles and agglomerates using direct-reading instruments and filter-based samples to characterize workplace aerosols by particle number, mass, size, composition, and morphology. Sampling was repeated for tasks in three work areas (fab, subfab, wastewater treatment) at a facility using engineered nanoparticles for CMP. Real-time measurements were collected using a condensation particle counter (CPC), optical particle counter, and scanning mobility particle spectrometer (SMPS). Filter-based samples were analyzed for total mass or the respirable fraction, and for specific metals of interest. Additional air sample filters were analyzed by transmission electron microscopy with energy dispersive x-ray spectroscopy (TEM/EDX) for elemental identification and to provide data on particle size, morphology, and concentration. Peak concentrations measured on the CPC ranged from 1 to 16 particles per cubic centimeter (P cm(-3)) for background and from 4 to 74 P cm(-3) during tasks sampled in the fab; from 1 to 60 P cm(-3) for background and from 3 to 84 P cm(-3) for tasks sampled in the subfab; and from 1160 to 45 894 P cm(-3) for background and from 1710 to 45 519 P cm(-3) during wastewater treatment system filter change tasks. Significant variability was seen among the repeated task measurements and among background comparisons in each area. Several data analysis methods were used to compare each set of task and background measurements. Increased concentrations of respirable particles were identified for some tasks sampled in each work area, although of relatively low magnitude and inconsistently among repeated measurements for specific tasks. Measurements with a portable SMPS indicated that nanoparticle number concentrations (channels 11.5-115.5nm) increased above background levels by 3.2 P cm(-3) during CMP tool set-up in the fab area but were not elevated when changing filters for the CMP wastewater treatment system. All results from mass concentration analysis were below the limits of detection. Characterization by TEM/EDX identified structures containing the elements of interest (Al, Si), primarily as agglomerates or aggregates in the 100-1000nm size range. Although health-based occupational exposure limits have not been established for nanoscale alumina, silica, or ceria, the measured concentrations by number and mass were below currently proposed benchmarks or reference values for poorly soluble low-toxicity nanoparticles.

Quantity processing in deaf and hard of hearing children: evidence from symbolic and nonsymbolic comparison tasks.

PubMed

Rodríguez-Santos, José Miguel; Calleja, Marina; García-Orza, Javier; Iza, Mauricio; Damas, Jesús

2014-01-01

Deaf children usually achieve lower scores on numerical tasks than normally hearing peers. Explanations for mathematical disabilities in hearing children are based on quantity representation deficits (Geary, 1994) or on deficits in accessing these representations (Rousselle & Noël, 2008). The present study aimed to verify, by means of symbolic (Arabic digits) and nonsymbolic (dot constellations and hands) magnitude comparison tasks, whether deaf children show deficits in representations or in accessing numerical representations. The study participants were 10 prelocutive deaf children and 10 normally hearing children. Numerical distance and magnitude were manipulated. Response time (RT) analysis showed similar magnitude and distance effects in both groups on the 3 tasks. However, slower RTs were observed among the deaf participants on the symbolic task alone. These results suggest that although both groups' quantity representations were similar, the deaf group experienced a delay in accessing representations from symbolic codes.

A Measure of Search Efficiency in a Real World Search Task (PREPRINT)

DTIC Science & Technology

2009-02-16

Search Task 5a. CONTRACT NUMBER N00173-08-1-G030 5b. GRANT NUMBER NRL BAA 08-09, 55-07-01 5c. PROGRAM ELEMENT NUMBER 0602782N 6. AUTHOR(S... Beck , Melissa R. Ph.D (LSU) Maura C. Lohrenz (NRL Code 7440.1) J. Gregory Trafton (NRL Code 5515) 5d. PROJECT NUMBER 08294 5e. TASK NUMBER... Beck 19b. TELEPHONE NUMBER (Include area code) (225)578-7214 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 A measure of search

Reliability of drivers in urban intersections.

PubMed

Gstalter, Herbert; Fastenmeier, Wolfgang

2010-01-01

The concept of human reliability has been widely used in industrial settings by human factors experts to optimise the person-task fit. Reliability is estimated by the probability that a task will successfully be completed by personnel in a given stage of system operation. Human Reliability Analysis (HRA) is a technique used to calculate human error probabilities as the ratio of errors committed to the number of opportunities for that error. To transfer this notion to the measurement of car driver reliability the following components are necessary: a taxonomy of driving tasks, a definition of correct behaviour in each of these tasks, a list of errors as deviations from the correct actions and an adequate observation method to register errors and opportunities for these errors. Use of the SAFE-task analysis procedure recently made it possible to derive driver errors directly from the normative analysis of behavioural requirements. Driver reliability estimates could be used to compare groups of tasks (e.g. different types of intersections with their respective regulations) as well as groups of drivers' or individual drivers' aptitudes. This approach was tested in a field study with 62 drivers of different age groups. The subjects drove an instrumented car and had to complete an urban test route, the main features of which were 18 intersections representing six different driving tasks. The subjects were accompanied by two trained observers who recorded driver errors using standardized observation sheets. Results indicate that error indices often vary between both the age group of drivers and the type of driving task. The highest error indices occurred in the non-signalised intersection tasks and the roundabout, which exactly equals the corresponding ratings of task complexity from the SAFE analysis. A comparison of age groups clearly shows the disadvantage of older drivers, whose error indices in nearly all tasks are significantly higher than those of the other groups. The vast majority of these errors could be explained by high task load in the intersections, as they represent difficult tasks. The discussion shows how reliability estimates can be used in a constructive way to propose changes in car design, intersection layout and regulation as well as driver training.

Intolerance for discomfort among smokers: comparison of smoking-specific and non-specific measures to smoking history and patterns.

PubMed

Sirota, Alan D; Rohsenow, Damaris J; Dolan, Sara L; Martin, Rosemarie A; Kahler, Christopher W

2013-03-01

Intolerance of discomfort associated with recent smoking cessation has been studied with only one smoking-specific questionnaire. The present study investigates the extent to which the previously validated Intolerance for Smoking Abstinence Discomfort Questionnaire (IDQ-S) scales share variance with (a) laboratory measures of distress tolerance (Paced Serial Addition Task and a breath-holding task) that have themselves been validated against smoking history, (b) the cold pressor task (not previously validated for smoking), and (c) an anxiety sensitivity questionnaire previously used for a similar purpose. The study then tests the hypothesis that the IDQ-S scales will have a higher correlation with smoking rate and dependence and with number and length of past smoking cessation attempts than with anxiety sensitivity or behavioral distress tolerance tasks do, since those measures are not smoking-specific. Sixty daily smokers recruited from the community completed the measures. The behavioral tasks and anxiety sensitivity shared little common variance. Anxiety sensitivity correlated more highly with IDQ-S than did the behavioral tasks but only 27% of variance was shared with the IDQ-S Withdrawal Intolerance; no distress tolerance measure correlated significantly with the IDQ-S Lack of Cognitive Coping scale. Only the IDQ-S scales correlated significantly with nicotine dependence, rate and past cessation: Withdrawal Intolerance with nicotine dependence and rate, and Lack of Cognitive Coping with fewer quit attempts. The smoking-specific measure of intolerance for discomfort may be more useful in smoking research than the less specific measures of distress tolerance. Published by Elsevier Ltd.

The Influence of Load and Speed on Individuals' Movement Behavior.

PubMed

Frost, David M; Beach, Tyson A C; Callaghan, Jack P; McGill, Stuart M

2015-09-01

Because individuals' movement patterns have been linked to their risk of future injury, movement evaluations have become a topic of interest. However, if individuals adapt their movement behavior in response to the demands of a task, the utility of evaluations comprising only low-demand activities could have limited application with regard to the prediction of future injury. This investigation examined the impact of load and speed on individuals' movement behavior. Fifty-two firefighters performed 5 low-demand (i.e., light load, low movement speed) whole-body tasks (i.e., lift, squat, lunge, push, and pull). Each task was then modified by increasing the speed, external load, or speed and load. Select measures of motion were used to characterize the performance of each task, and comparisons were made between conditions. The participants adapted their movement behavior in response to the external demands of a task (64 and 70% of all the variables were influenced [p ≤ 0.05] by changing the load and speed, respectively), but in a manner unique to the task and type of demand. The participants exhibited greater spine and frontal plane knee motion in response to an increase in speed when compared with increasing loads. However, there were a large number of movement strategies exhibited by individual firefighters that differed from the group's response. The data obtained here imply that individuals may not be physically prepared to perform safely or effectively when a task's demands are elevated simply because they exhibit the ability to perform a low-demand activity with competence. Therefore, movement screens comprising only low-demand activities may not adequately reflect an individual's capacity, or their risk of injury, and could adversely affect any recommendations that are made for training or job performance.

Imitating actions on objects in early-onset and regressive autism: Effects and implications of task characteristics on performance

PubMed Central

Rogers, Sally J.; Young, Gregory S.; Cook, Ian; Giolzetti, Angelo; Ozonoff, Sally

2010-01-01

This study was designed to examine the nature of object imitation performance in early autism. We hypothesized that imitation would be relatively preserved when behaviors on objects resulted in salient instrumental effects. We designed tasks in which, in one condition, the motor action resulted in a salient, meaningful effect on an object, whereas in the other condition, the same action resulted in a less salient effect because of differing object characteristics. The motor aspects of the tasks did not vary across conditions. Four participant groups of 2- to 5-year-olds were examined: 17 children with early-onset autism, 24 children with regressive onset autism, 22 children with developmental delays, and 22 children with typical development. Groups were matched on nonverbal skills, and differences in verbal development were examined as a moderator of imitative ability. Results revealed an interaction of group by condition, with the combined autism group failing more tasks than the combined comparison groups, and failing more tasks in the less salient condition than in the more salient condition, as hypothesized. Analyses of autism subgroups revealed these effects were primarily because of the regression onset group. Accuracy of motor performance was examined by analyzing errors. Among children passing imitative acts, there were no group differences and no condition effects in the number, type, or pattern of performance errors. Among children passing the tasks, the group with autism did not demonstrate more emulation errors (imitating the goal but not the means) than other groups. There was no evidence that either motor or attentional aspects of the tasks contributed to the poorer imitative performance of the children with autism. PMID:20102648

Training, Retention, and Transfer of Data Entry Perceptual and Motoric Processes Over Long Retention Intervals

NASA Technical Reports Server (NTRS)

Kole, James A.; Schneider, Vivian I.; Healy, Alice F.; Barshi, Immanuel

2017-01-01

Subjects trained in a standard data entry task, which involved typing numbers (e.g., 5421) using their right hands. At test (6 months post-training), subjects completed the standard task, followed by a left-hand variant (typing with their left hands) that involved the same perceptual, but different motoric, processes as the standard task. At a second test (8 months post-training), subjects completed the standard task, followed by a code variant (translating letters into digits, then typing the digits with their right hands) that involved different perceptual, but the same motoric, processes as the standard task. For each of the three tasks, half the trials were trained numbers (old) and half were new. Repetition priming (faster response times to old than new numbers) was found for each task. Repetition priming for the standard task reflects retention of trained numbers; for the left-hand variant reflects transfer of perceptual processes; and for the code variant reflects transfer of motoric processes. There was thus evidence for both specificity and generalizability of training data entry perceptual and motoric processes over very long retention intervals.

Evaluation of scheduling techniques for payload activity planning

NASA Technical Reports Server (NTRS)

Bullington, Stanley F.

1991-01-01

Two tasks related to payload activity planning and scheduling were performed. The first task involved making a comparison of space mission activity scheduling problems with production scheduling problems. The second task consisted of a statistical analysis of the output of runs of the Experiment Scheduling Program (ESP). Details of the work which was performed on these two tasks are presented.

Effects of Planning on Task Load, Knowledge, and Tool Preference: A Comparison of Two Tools

ERIC Educational Resources Information Center

Bonestroo, Wilco J.; de Jong, Ton

2012-01-01

Self-regulated learners are expected to plan their own learning. Because planning is a complex task, it is not self-evident that all learners can perform this task successfully. In this study, we examined the effects of two planning support tools on the quality of created plans, planning behavior, task load, and acquired knowledge. Sixty-five…

Reinforcer Control by Comparison-Stimulus Color and Location in a Delayed Matching-to-Sample Task

ERIC Educational Resources Information Center

Alsop, Brent; Jones, B. Max

2008-01-01

Six pigeons were trained in a delayed matching-to-sample task involving bright- and dim-yellow samples on a central key, a five-peck response requirement to either sample, a constant 1.5-s delay, and the presentation of comparison stimuli composed of red on the left key and green on the right key or vice versa. Green-key responses were…

Distilled single-cell genome sequencing and de novo assembly for sparse microbial communities.

PubMed

Taghavi, Zeinab; Movahedi, Narjes S; Draghici, Sorin; Chitsaz, Hamidreza

2013-10-01

Identification of every single genome present in a microbial sample is an important and challenging task with crucial applications. It is challenging because there are typically millions of cells in a microbial sample, the vast majority of which elude cultivation. The most accurate method to date is exhaustive single-cell sequencing using multiple displacement amplification, which is simply intractable for a large number of cells. However, there is hope for breaking this barrier, as the number of different cell types with distinct genome sequences is usually much smaller than the number of cells. Here, we present a novel divide and conquer method to sequence and de novo assemble all distinct genomes present in a microbial sample with a sequencing cost and computational complexity proportional to the number of genome types, rather than the number of cells. The method is implemented in a tool called Squeezambler. We evaluated Squeezambler on simulated data. The proposed divide and conquer method successfully reduces the cost of sequencing in comparison with the naïve exhaustive approach. Squeezambler and datasets are available at http://compbio.cs.wayne.edu/software/squeezambler/.

Improving pairwise comparison of protein sequences with domain co-occurrence

PubMed Central

Gascuel, Olivier

2018-01-01

Comparing and aligning protein sequences is an essential task in bioinformatics. More specifically, local alignment tools like BLAST are widely used for identifying conserved protein sub-sequences, which likely correspond to protein domains or functional motifs. However, to limit the number of false positives, these tools are used with stringent sequence-similarity thresholds and hence can miss several hits, especially for species that are phylogenetically distant from reference organisms. A solution to this problem is then to integrate additional contextual information to the procedure. Here, we propose to use domain co-occurrence to increase the sensitivity of pairwise sequence comparisons. Domain co-occurrence is a strong feature of proteins, since most protein domains tend to appear with a limited number of other domains on the same protein. We propose a method to take this information into account in a typical BLAST analysis and to construct new domain families on the basis of these results. We used Plasmodium falciparum as a case study to evaluate our method. The experimental findings showed an increase of 14% of the number of significant BLAST hits and an increase of 25% of the proteome area that can be covered with a domain. Our method identified 2240 new domains for which, in most cases, no model of the Pfam database could be linked. Moreover, our study of the quality of the new domains in terms of alignment and physicochemical properties show that they are close to that of standard Pfam domains. Source code of the proposed approach and supplementary data are available at: https://gite.lirmm.fr/menichelli/pairwise-comparison-with-cooccurrence PMID:29293498

Number Conservation is Related to Children’s Prefrontal Inhibitory Control: An fMRI Study of a Piagetian Task

PubMed Central

Simon, Grégory; Rossi, Sandrine; Cassotti, Mathieu; Pineau, Arlette; Houdé, Olivier

2012-01-01

Although young children can accurately determine that two rows contain the same number of coins when they are placed in a one-to-one correspondence, children younger than 7 years of age erroneously think that the longer row contains more coins when the coins in one of the rows are spread apart. To demonstrate that prefrontal inhibitory control is necessary to succeed at this task (Piaget’s conservation-of-number task), we studied the relationship between the percentage of BOLD signal changes in the brain areas activated in this developmental task and behavioral performance on a Stroop task and a Backward Digit Span task. The level of activation in the right insula/inferior frontal gyrus was selectively related to inhibitory control efficiency (i.e., the Stroop task), whereas the activation in the left intraparietal sulcus (IPS) was selectively related to the ability to manipulate numerical information in working memory (i.e., the Backward Digit Span task). Taken together, the results indicate that to acquire number conservation, children’s brains must not only activate the reversibility of cognitive operations (supported by the IPS) but also inhibit a misleading length-equal-number strategy (supported by the right insula/inferior frontal gyrus). PMID:22815825

All for one but not one for all: how multiple number representations are recruited in one numerical task.

PubMed

Wood, Guilherme; Nuerk, Hans-Christoph; Moeller, Korbinian; Geppert, Barbara; Schnitker, Ralph; Weber, Jochen; Willmes, Klaus

2008-01-02

Number processing recruits a complex network of multiple numerical representations. Usually the components of this network are examined in a between-task approach with the disadvantage of relying upon different instructions, tasks, and inhomogeneous stimulus sets across different studies. A within-task approach may avoid these disadvantages and access involved numerical representations more specifically. In the present study we employed a within-task approach to investigate numerical representations activated in the number bisection task (NBT) using parametric rapid event-related fMRI. Participants were to judge whether the central number of a triplet was also its arithmetic mean (e.g. 23_26_29) or not (e.g. 23_25_29). Activation in the left inferior parietal cortex was associated with the deployment of arithmetic fact knowledge, while activation of the intraparietal cortex indicated more intense magnitude processing, instrumental aspects of calculation and integration of the base-10 structure of two-digit numbers. These results replicate evidence from the literature. Furthermore, activation in the dorsolateral and ventrolateral prefrontal cortex revealed mechanisms of feature monitoring and inhibition as well as allocation of cognitive resources recruited to solve a specific triplet. We conclude that the network of numerical representations should rather be studied in a within-task approach than in varying between-task approaches.

Detecting and Quantifying Mind Wandering during Simulated Driving.

PubMed

Baldwin, Carryl L; Roberts, Daniel M; Barragan, Daniela; Lee, John D; Lerner, Neil; Higgins, James S

2017-01-01

Mind wandering is a pervasive threat to transportation safety, potentially accounting for a substantial number of crashes and fatalities. In the current study, mind wandering was induced through completion of the same task for 5 days, consisting of a 20-min monotonous freeway-driving scenario, a cognitive depletion task, and a repetition of the 20-min driving scenario driven in the reverse direction. Participants were periodically probed with auditory tones to self-report whether they were mind wandering or focused on the driving task. Self-reported mind wandering frequency was high, and did not statistically change over days of participation. For measures of driving performance, participant labeled periods of mind wandering were associated with reduced speed and reduced lane variability, in comparison to periods of on task performance. For measures of electrophysiology, periods of mind wandering were associated with increased power in the alpha band of the electroencephalogram (EEG), as well as a reduction in the magnitude of the P3a component of the event related potential (ERP) in response to the auditory probe. Results support that mind wandering has an impact on driving performance and the associated change in driver's attentional state is detectable in underlying brain physiology. Further, results suggest that detecting the internal cognitive state of humans is possible in a continuous task such as automobile driving. Identifying periods of likely mind wandering could serve as a useful research tool for assessment of driver attention, and could potentially lead to future in-vehicle safety countermeasures.

Detecting and Quantifying Mind Wandering during Simulated Driving

PubMed Central

Baldwin, Carryl L.; Roberts, Daniel M.; Barragan, Daniela; Lee, John D.; Lerner, Neil; Higgins, James S.

2017-01-01

Mind wandering is a pervasive threat to transportation safety, potentially accounting for a substantial number of crashes and fatalities. In the current study, mind wandering was induced through completion of the same task for 5 days, consisting of a 20-min monotonous freeway-driving scenario, a cognitive depletion task, and a repetition of the 20-min driving scenario driven in the reverse direction. Participants were periodically probed with auditory tones to self-report whether they were mind wandering or focused on the driving task. Self-reported mind wandering frequency was high, and did not statistically change over days of participation. For measures of driving performance, participant labeled periods of mind wandering were associated with reduced speed and reduced lane variability, in comparison to periods of on task performance. For measures of electrophysiology, periods of mind wandering were associated with increased power in the alpha band of the electroencephalogram (EEG), as well as a reduction in the magnitude of the P3a component of the event related potential (ERP) in response to the auditory probe. Results support that mind wandering has an impact on driving performance and the associated change in driver’s attentional state is detectable in underlying brain physiology. Further, results suggest that detecting the internal cognitive state of humans is possible in a continuous task such as automobile driving. Identifying periods of likely mind wandering could serve as a useful research tool for assessment of driver attention, and could potentially lead to future in-vehicle safety countermeasures. PMID:28848414

Training apartment upkeep skills to rehabilitation clients: a comparison of task analytic strategies.

PubMed Central

Williams, G E; Cuvo, A J

1986-01-01

The research was designed to validate procedures to teach apartment upkeep skills to severely handicapped clients with various categorical disabilities. Methodological features of this research included performance comparisons between general and specific task analyses, effect of an impasse correction baseline procedure, social validation of training goals, natural environment assessments and contingencies, as well as long-term follow-up. Subjects were taught to perform upkeep responses on their air conditioner-heating unit, electric range, refrigerator, and electrical appliances within the context of a multiple-probe across subjects experimental design. The results showed acquisition, long-term maintenance, and generalization of the upkeep skills to a nontraining apartment. General task analyses were recommended for assessment and specific task analyses for training. The impasse correction procedure generally did not produce acquisition. PMID:3710947

Number sense and mathematics: Which, when and how?

PubMed

Tosto, Maria G; Petrill, Stephen A; Malykh, Sergey; Malki, Karim; Haworth, Claire M A; Mazzocco, Michele M M; Thompson, Lee; Opfer, John; Bogdanova, Olga Y; Kovas, Yulia

2017-10-01

Individual differences in number sense correlate with mathematical ability and performance, although the presence and strength of this relationship differs across studies. Inconsistencies in the literature may stem from heterogeneity of number sense and mathematical ability constructs. Sample characteristics may also play a role as changes in the relationship between number sense and mathematics may differ across development and cultural contexts. In this study, 4,984 16-year-old students were assessed on estimation ability, one aspect of number sense. Estimation was measured using 2 different tasks: number line and dot-comparison. Using cognitive and achievement data previously collected from these students at ages 7, 9, 10, 12, and 14, the study explored for which of the measures and when in development these links are observed, and how strong these links are and how much these links are moderated by other cognitive abilities. The 2 number sense measures correlated modestly with each other (r = .22), but moderately with mathematics at age 16. Both measures were also associated with earlier mathematics; but this association was uneven across development and was moderated by other cognitive abilities. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Forensic comparison and matching of fingerprints: using quantitative image measures for estimating error rates through understanding and predicting difficulty.

PubMed

Kellman, Philip J; Mnookin, Jennifer L; Erlikhman, Gennady; Garrigan, Patrick; Ghose, Tandra; Mettler, Everett; Charlton, David; Dror, Itiel E

2014-01-01

Latent fingerprint examination is a complex task that, despite advances in image processing, still fundamentally depends on the visual judgments of highly trained human examiners. Fingerprints collected from crime scenes typically contain less information than fingerprints collected under controlled conditions. Specifically, they are often noisy and distorted and may contain only a portion of the total fingerprint area. Expertise in fingerprint comparison, like other forms of perceptual expertise, such as face recognition or aircraft identification, depends on perceptual learning processes that lead to the discovery of features and relations that matter in comparing prints. Relatively little is known about the perceptual processes involved in making comparisons, and even less is known about what characteristics of fingerprint pairs make particular comparisons easy or difficult. We measured expert examiner performance and judgments of difficulty and confidence on a new fingerprint database. We developed a number of quantitative measures of image characteristics and used multiple regression techniques to discover objective predictors of error as well as perceived difficulty and confidence. A number of useful predictors emerged, and these included variables related to image quality metrics, such as intensity and contrast information, as well as measures of information quantity, such as the total fingerprint area. Also included were configural features that fingerprint experts have noted, such as the presence and clarity of global features and fingerprint ridges. Within the constraints of the overall low error rates of experts, a regression model incorporating the derived predictors demonstrated reasonable success in predicting objective difficulty for print pairs, as shown both in goodness of fit measures to the original data set and in a cross validation test. The results indicate the plausibility of using objective image metrics to predict expert performance and subjective assessment of difficulty in fingerprint comparisons.

Person-independent facial expression analysis by fusing multiscale cell features

NASA Astrophysics Data System (ADS)

Zhou, Lubing; Wang, Han

2013-03-01

Automatic facial expression recognition is an interesting and challenging task. To achieve satisfactory accuracy, deriving a robust facial representation is especially important. A novel appearance-based feature, the multiscale cell local intensity increasing patterns (MC-LIIP), to represent facial images and conduct person-independent facial expression analysis is presented. The LIIP uses a decimal number to encode the texture or intensity distribution around each pixel via pixel-to-pixel intensity comparison. To boost noise resistance, MC-LIIP carries out comparison computation on the average values of scalable cells instead of individual pixels. The facial descriptor fuses region-based histograms of MC-LIIP features from various scales, so as to encode not only textural microstructures but also the macrostructures of facial images. Finally, a support vector machine classifier is applied for expression recognition. Experimental results on the CK+ and Karolinska directed emotional faces databases show the superiority of the proposed method.

Dissociation between arithmetic relatedness and distance effects is modulated by task properties: an ERP study comparing explicit vs. implicit arithmetic processing.

PubMed

Avancini, Chiara; Galfano, Giovanni; Szűcs, Dénes

2014-12-01

Event-related potential (ERP) studies have detected several characteristic consecutive amplitude modulations in both implicit and explicit mental arithmetic tasks. Implicit tasks typically focused on the arithmetic relatedness effect (in which performance is affected by semantic associations between numbers) while explicit tasks focused on the distance effect (in which performance is affected by the numerical difference of to-be-compared numbers). Both task types elicit morphologically similar ERP waves which were explained in functionally similar terms. However, to date, the relationship between these tasks has not been investigated explicitly and systematically. In order to fill this gap, here we examined whether ERP effects and their underlying cognitive processes in implicit and explicit mental arithmetic tasks differ from each other. The same group of participants performed both an implicit number-matching task (in which arithmetic knowledge is task-irrelevant) and an explicit arithmetic-verification task (in which arithmetic knowledge is task-relevant). 129-channel ERP data differed substantially between tasks. In the number-matching task, the arithmetic relatedness effect appeared as a negativity over left-frontal electrodes whereas the distance effect was more prominent over right centro-parietal electrodes. In the verification task, all probe types elicited similar N2b waves over right fronto-central electrodes and typical centro-parietal N400 effects over central electrodes. The distance effect appeared as an early-rising, long-lasting left parietal negativity. We suggest that ERP effects in the implicit task reflect access to semantic memory networks and to magnitude discrimination, respectively. In contrast, effects of expectation violation are more prominent in explicit tasks and may mask more delicate cognitive processes. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Dissociation between arithmetic relatedness and distance effects is modulated by task properties: An ERP study comparing explicit vs. implicit arithmetic processing

PubMed Central

Avancini, Chiara; Galfano, Giovanni; Szűcs, Dénes

2014-01-01

Event-related potential (ERP) studies have detected several characteristic consecutive amplitude modulations in both implicit and explicit mental arithmetic tasks. Implicit tasks typically focused on the arithmetic relatedness effect (in which performance is affected by semantic associations between numbers) while explicit tasks focused on the distance effect (in which performance is affected by the numerical difference of to-be-compared numbers). Both task types elicit morphologically similar ERP waves which were explained in functionally similar terms. However, to date, the relationship between these tasks has not been investigated explicitly and systematically. In order to fill this gap, here we examined whether ERP effects and their underlying cognitive processes in implicit and explicit mental arithmetic tasks differ from each other. The same group of participants performed both an implicit number-matching task (in which arithmetic knowledge is task-irrelevant) and an explicit arithmetic-verification task (in which arithmetic knowledge is task-relevant). 129-channel ERP data differed substantially between tasks. In the number-matching task, the arithmetic relatedness effect appeared as a negativity over left-frontal electrodes whereas the distance effect was more prominent over right centro-parietal electrodes. In the verification task, all probe types elicited similar N2b waves over right fronto-central electrodes and typical centro-parietal N400 effects over central electrodes. The distance effect appeared as an early-rising, long-lasting left parietal negativity. We suggest that ERP effects in the implicit task reflect access to semantic memory networks and to magnitude discrimination, respectively. In contrast, effects of expectation violation are more prominent in explicit tasks and may mask more delicate cognitive processes. PMID:25450162

Individual Difference Relations in Psychometric and Experimental Cognitive Tasks. Final Report. No. 163.

ERIC Educational Resources Information Center

Carroll, John B.

Fifty-five recent studies of individual differences (IDs) in elementary cognitive tasks (ECTs) are reviewed. Twenty-five data sets are examined, analyzed, or reanalyzed by factor analysis. The following promising dimensions are identified: basic perceptual processes, reaction and movement times, mental comparison and recognition tasks, retrieval…

Exploring methodological frameworks for a mental task-based near-infrared spectroscopy brain-computer interface.

PubMed

Weyand, Sabine; Takehara-Nishiuchi, Kaori; Chau, Tom

2015-10-30

Near-infrared spectroscopy (NIRS) brain-computer interfaces (BCIs) enable users to interact with their environment using only cognitive activities. This paper presents the results of a comparison of four methodological frameworks used to select a pair of tasks to control a binary NIRS-BCI; specifically, three novel personalized task paradigms and the state-of-the-art prescribed task framework were explored. Three types of personalized task selection approaches were compared, including: user-selected mental tasks using weighted slope scores (WS-scores), user-selected mental tasks using pair-wise accuracy rankings (PWAR), and researcher-selected mental tasks using PWAR. These paradigms, along with the state-of-the-art prescribed mental task framework, where mental tasks are selected based on the most commonly used tasks in literature, were tested by ten able-bodied participants who took part in five NIRS-BCI sessions. The frameworks were compared in terms of their accuracy, perceived ease-of-use, computational time, user preference, and length of training. Most notably, researcher-selected personalized tasks resulted in significantly higher accuracies, while user-selected personalized tasks resulted in significantly higher perceived ease-of-use. It was also concluded that PWAR minimized the amount of data that needed to be collected; while, WS-scores maximized user satisfaction and minimized computational time. In comparison to the state-of-the-art prescribed mental tasks, our findings show that overall, personalized tasks appear to be superior to prescribed tasks with respect to accuracy and perceived ease-of-use. The deployment of personalized rather than prescribed mental tasks ought to be considered and further investigated in future NIRS-BCI studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Executive Functions are not Affected by 24 Hours of Sleep Deprivation: A Color-Word Stroop Task Study.

PubMed

Dixit, Abhinav; Mittal, Tushar

2015-01-01

Sleep is an important factor affecting cognitive performance. Sleep deprivation results in fatigue, lack of concentration, confusion and sleepiness along with anxiety, depression and irritability. Sleep deprivation can have serious consequences in professions like armed forces and medicine where quick decisions and actions need to be taken. Color-Word Stroop task is one of the reliable tests to assess attention and it analyzes the processing of information in two dimensions i.e., reading of words and naming of colour. The evidence regarding the effect of sleep deprivation on Stroop interference is conflicting. The present study evaluated the effect of 24 hours of sleep deprivation on reaction time and interference in Stroop task. The present study was done on 30 healthy male medical student volunteers in the age group of 18-25 years after taking their consent and clearance from Institute Ethics Committee. Recordings of Stroop task were at three times: baseline (between 7-9 am), after 12 hours (7-9 pm) and after 24 hours (7-9 am, next day). The subjects were allowed to perform normal daily activities. The study revealed a significant increase in reaction time after 24 hours of sleep deprivation in comparison to baseline and after 12 hours of sleep deprivation. There was no significant change in interference and facilitation after sleep deprivation in comparison to baseline. The number of errors also did not show any significant change after sleep deprivation. The study indicated that there was slowing of responses without change in executive functions after 24 hours of sleep deprivation. It is probable that 24 hours of sleep deprivation does not bring about change in areas of brain affecting executive functions in healthy individuals who have normal sleep cycle. The present study indicated that in professions like armed forces and medicine working 24 hours at a stretch can lead to decrease in motor responses without affecting information processing and judgment ability.

An Investigation of the Use of Real-time Image Mosaicing for Facilitating Global Spatial Awareness in Visual Search

NASA Astrophysics Data System (ADS)

Soung Yee, Anthony

Three experiments have been completed to investigate whether and how a software technique called real-time image mosaicing applied to a restricted field of view (FOV) might influence target detection and path integration performance in simulated aerial search scenarios, representing local and global spatial awareness tasks respectively. The mosaiced FOV (mFOV) was compared to single FOV (sFOV) and one with double the single size (dFOV). In addition to advancing our understanding of visual information in mosaicing, the present study examines the advantages and limitations of a number of metrics used to evaluate performance in path integration tasks, with particular attention paid to measuring performance in identifying complex routes. The highlights of the results are summarized as follows, according to Experiments 1 through 3 respectively. 1. A novel response method for evaluating route identification performance was developed. The surmised benefits of the mFOV relative to sFOV and dFOV revealed no significant differences in performance for the relatively simple route shapes tested. Compared to the mFOV and dFOV conditions, target detection performance in the local task was found to be superior in the sFOV condition. 2. In order to appropriately quantify the observed differences in complex route selections made by the participants, a novel analysis method was developed using the Thurstonian Paired Comparisons Method. 3. To investigate the effect of display size and elevation angle (EA) in a complex route environment, a 2x3 experiment was conducted for the two spatial tasks, at a height selected from Experiment 2. Although no significant differences were found in the target detection task, contrasts in the Paired Comparisons Method results revealed that route identification performance were as hypothesised: mFOV > dFOV > sFOV for EA = 90°. Results were similar for EA = 45°, but with mFOV being no different than dFOV. As hypothesised, EA was found to have an effect on route selection performance, with a top down view performing better than an angled view for the mFOV and sFOV conditions.

Emergency Medical Technician Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains the occupational duty/task lists for 12 duties in the occupation of emergency medical technician. Each duty is divided into a number of tasks. A separate page for each duty lists the task with its code number and columns to indicate whether that particular duty has been taught and to provide space for comments. The 12 duties…

ARBAN-A new method for analysis of ergonomic effort.

PubMed

Holzmann, P

1982-06-01

ARBAN is a method for the ergonomic analysis of work, including work situations which involve widely differing body postures and loads. The idea of the method is thal all phases of the analysis process that imply specific knowledge on ergonomics are teken over by filming equipment and a computer routine. All tasks that must be carried out by the investigator in the process of analysis are so designed that they appear as evident by the use of systematic common sense. The ARBAN analysis method contains four steps: 1. Recording of the workplace situation on video or film. 2. Coding the posture and load situation at a number of closely spaced 'frozen' situations. 3. Computerisation. 4. Evaluation of the results. The computer calculates figures for the total ergonomic stress on the whole body as well as on different parts of the body separately. They are presented as 'Ergonomic stress/ time curves', where the heavy load situations occur as peaks of the curve. The work cycle may also be divided into different tasks, where the stress and duration patterns can be compared. The integral of the curves are calculated for single-figure comparison of different tasks as well as different work situations.

Functional neural bases of numerosity judgments in healthy adults born preterm.

PubMed

Clark, Caron A C; Liu, Yating; Wright, Nicolas Lee Abbot; Bedrick, Alan; Edgin, Jamie O

2017-11-01

High rates of mathematics learning disabilities among individuals born preterm (<37weeksGA) have spurred calls for a greater understanding of the nature of these weaknesses and their neural underpinnings. Groups of healthy, high functioning young adults born preterm and full term (n=20) completed a symbolic and non-symbolic magnitude comparison task while undergoing functional MRI scanning. Collectively, participants showed activation in superior and inferior frontal and parietal regions previously linked to numeric processing when comparing non-symbolic magnitude arrays separated by small numeric distances. Simultaneous deactivation of the default mode network also was evident during these trials. Individuals born preterm showed increased signal change relative to their full term peers in right inferior frontal and parietal regions when comparing the non-symbolic magnitude arrays. Elevated signal change during non-symbolic task blocks was associated with poorer performance on a calculation task administered outside of the scanner. These findings indicate that healthy, high-functioning adults born preterm may recruit fronto-parietal networks more extensively when processing non-symbolic magnitudes, suggesting that approximate number system training may be an inroad for early intervention to prevent mathematics difficulties in this population. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparison of the effects of mobile technology AAC apps on programming visual scene displays.

PubMed

Caron, Jessica; Light, Janice; Davidoff, Beth E; Drager, Kathryn D R

2017-12-01

Parents and professionals who work with individuals who use augmentative and alternative communication (AAC) face tremendous time pressures, especially when programming vocabulary in AAC technologies. System design (from programming functions to layout options) necessitates a range of skills related to operational competence and can impose intensive training demands for communication partners. In fact, some AAC applications impose considerable learning demands, which can lead to increased time to complete the same programming tasks. A within-subject design was used to investigate the comparative effects of three visual scene display AAC apps (GoTalk Now, AutisMate, EasyVSD) on the programming times for three off-line programming activities, by adults who were novices to programming AAC apps. The results indicated all participants were able to create scenes and add hotspots during off-line programming tasks with minimal self-guided training. The AAC app that had the least number of programming steps, EasyVSD, resulted in the fastest completion times across the three programming tasks. These results suggest that by simplifying the operational requirements of AAC apps the programming time is reduced, which may allow partners to better support individuals who use AAC.

A Mobile, Map-Based Tasking Interface for Human-Robot Interaction

DTIC Science & Technology

2010-12-01

A MOBILE, MAP-BASED TASKING INTERFACE FOR HUMAN-ROBOT INTERACTION By Eli R. Hooten Thesis Submitted to the Faculty of the Graduate School of...SUBTITLE A Mobile, Map-Based Tasking Interface for Human-Robot Interaction 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...3 II.1 Interactive Modalities and Multi-Touch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 II.2

Is Handwriting Performance Affected by the Writing Surface? Comparing Preschoolers', Second Graders', and Adults' Writing Performance on a Tablet vs. Paper.

PubMed

Gerth, Sabrina; Klassert, Annegret; Dolk, Thomas; Fliesser, Michael; Fischer, Martin H; Nottbusch, Guido; Festman, Julia

2016-01-01

Due to their multifunctionality, tablets offer tremendous advantages for research on handwriting dynamics or for interactive use of learning apps in schools. Further, the widespread use of tablet computers has had a great impact on handwriting in the current generation. But, is it advisable to teach how to write and to assess handwriting in pre- and primary schoolchildren on tablets rather than on paper? Since handwriting is not automatized before the age of 10 years, children's handwriting movements require graphomotor and visual feedback as well as permanent control of movement execution during handwriting. Modifications in writing conditions, for instance the smoother writing surface of a tablet, might influence handwriting performance in general and in particular those of non-automatized beginning writers. In order to investigate how handwriting performance is affected by a difference in friction of the writing surface, we recruited three groups with varying levels of handwriting automaticity: 25 preschoolers, 27 second graders, and 25 adults. We administered three tasks measuring graphomotor abilities, visuomotor abilities, and handwriting performance (only second graders and adults). We evaluated two aspects of handwriting performance: the handwriting quality with a visual score and the handwriting dynamics using online handwriting measures [e.g., writing duration, writing velocity, strokes and number of inversions in velocity (NIV)]. In particular, NIVs which describe the number of velocity peaks during handwriting are directly related to the level of handwriting automaticity. In general, we found differences between writing on paper compared to the tablet. These differences were partly task-dependent. The comparison between tablet and paper revealed a faster writing velocity for all groups and all tasks on the tablet which indicates that all participants-even the experienced writers-were influenced by the lower friction of the tablet surface. Our results for the group-comparison show advancing levels in handwriting automaticity from preschoolers to second graders to adults, which confirms that our method depicts handwriting performance in groups with varying degrees of handwriting automaticity. We conclude that the smoother tablet surface requires additional control of handwriting movements and therefore might present an additional challenge for learners of handwriting.

Is Handwriting Performance Affected by the Writing Surface? Comparing Preschoolers', Second Graders', and Adults' Writing Performance on a Tablet vs. Paper

PubMed Central

Gerth, Sabrina; Klassert, Annegret; Dolk, Thomas; Fliesser, Michael; Fischer, Martin H.; Nottbusch, Guido; Festman, Julia

2016-01-01

Due to their multifunctionality, tablets offer tremendous advantages for research on handwriting dynamics or for interactive use of learning apps in schools. Further, the widespread use of tablet computers has had a great impact on handwriting in the current generation. But, is it advisable to teach how to write and to assess handwriting in pre- and primary schoolchildren on tablets rather than on paper? Since handwriting is not automatized before the age of 10 years, children's handwriting movements require graphomotor and visual feedback as well as permanent control of movement execution during handwriting. Modifications in writing conditions, for instance the smoother writing surface of a tablet, might influence handwriting performance in general and in particular those of non-automatized beginning writers. In order to investigate how handwriting performance is affected by a difference in friction of the writing surface, we recruited three groups with varying levels of handwriting automaticity: 25 preschoolers, 27 second graders, and 25 adults. We administered three tasks measuring graphomotor abilities, visuomotor abilities, and handwriting performance (only second graders and adults). We evaluated two aspects of handwriting performance: the handwriting quality with a visual score and the handwriting dynamics using online handwriting measures [e.g., writing duration, writing velocity, strokes and number of inversions in velocity (NIV)]. In particular, NIVs which describe the number of velocity peaks during handwriting are directly related to the level of handwriting automaticity. In general, we found differences between writing on paper compared to the tablet. These differences were partly task-dependent. The comparison between tablet and paper revealed a faster writing velocity for all groups and all tasks on the tablet which indicates that all participants—even the experienced writers—were influenced by the lower friction of the tablet surface. Our results for the group-comparison show advancing levels in handwriting automaticity from preschoolers to second graders to adults, which confirms that our method depicts handwriting performance in groups with varying degrees of handwriting automaticity. We conclude that the smoother tablet surface requires additional control of handwriting movements and therefore might present an additional challenge for learners of handwriting. PMID:27672372

Neural substrates related to auditory working memory comparisons in dyslexia: An fMRI study

PubMed Central

CONWAY, TIM; HEILMAN, KENNETH M.; GOPINATH, KAUNDINYA; PECK, KYUNG; BAUER, RUSSELL; BRIGGS, RICHARD W.; TORGESEN, JOSEPH K.; CROSSON, BRUCE

2010-01-01

Adult readers with developmental phonological dyslexia exhibit significant difficulty comparing pseudowords and pure tones in auditory working memory (AWM). This suggests deficient AWM skills for adults diagnosed with dyslexia. Despite behavioral differences, it is unknown whether neural substrates of AWM differ between adults diagnosed with dyslexia and normal readers. Prior neuroimaging of adults diagnosed with dyslexia and normal readers, and post-mortem findings of neural structural anomalies in adults diagnosed with dyslexia support the hypothesis of atypical neural activity in temporoparietal and inferior frontal regions during AWM tasks in adults diagnosed with dyslexia. We used fMRI during two binaural AWM tasks (pseudowords or pure tones comparisons) in adults diagnosed with dyslexia (n = 11) and normal readers (n = 11). For both AWM tasks, adults diagnosed with dyslexia exhibited greater activity in left posterior superior temporal (BA 22) and inferior parietal regions (BA 40) than normal readers. Comparing neural activity between groups and between stimuli contrasts (pseudowords vs. tones), adults diagnosed with dyslexia showed greater primary auditory cortex activity (BA 42; tones > pseudowords) than normal readers. Thus, greater activity in primary auditory, posterior superior temporal, and inferior parietal cortices during linguistic and non-linguistic AWM tasks for adults diagnosed with dyslexia compared to normal readers indicate differences in neural substrates of AWM comparison tasks. PMID:18577292

Number line estimation and complex mental calculation: Is there a shared cognitive process driving the two tasks?

PubMed

Montefinese, Maria; Semenza, Carlo

2018-05-17

It is widely accepted that different number-related tasks, including solving simple addition and subtraction, may induce attentional shifts on the so-called mental number line, which represents larger numbers on the right and smaller numbers on the left. Recently, it has been shown that different number-related tasks also employ spatial attention shifts along with general cognitive processes. Here we investigated for the first time whether number line estimation and complex mental arithmetic recruit a common mechanism in healthy adults. Participants' performance in two-digit mental additions and subtractions using visual stimuli was compared with their performance in a mental bisection task using auditory numerical intervals. Results showed significant correlations between participants' performance in number line bisection and that in two-digit mental arithmetic operations, especially in additions, providing a first proof of a shared cognitive mechanism (or multiple shared cognitive mechanisms) between auditory number bisection and complex mental calculation.

Challenging Tasks: What Happens When Challenging Tasks Are Used in Mixed Ability Middle School Mathematics Classrooms?

ERIC Educational Resources Information Center

Perkins, Karen

2016-01-01

The topics of decimals and polygons were taught to two classes by using challenging tasks, rather than the more conventional textbook approach. Students were given a pre-test and a post-test. A comparison between the two classes on the pre- and post-test was made. Prior to teaching through challenging tasks, students were surveyed about their…

Identifying effective connectivity parameters in simulated fMRI: a direct comparison of switching linear dynamic system, stochastic dynamic causal, and multivariate autoregressive models

PubMed Central

Smith, Jason F.; Chen, Kewei; Pillai, Ajay S.; Horwitz, Barry

2013-01-01

The number and variety of connectivity estimation methods is likely to continue to grow over the coming decade. Comparisons between methods are necessary to prune this growth to only the most accurate and robust methods. However, the nature of connectivity is elusive with different methods potentially attempting to identify different aspects of connectivity. Commonalities of connectivity definitions across methods upon which base direct comparisons can be difficult to derive. Here, we explicitly define “effective connectivity” using a common set of observation and state equations that are appropriate for three connectivity methods: dynamic causal modeling (DCM), multivariate autoregressive modeling (MAR), and switching linear dynamic systems for fMRI (sLDSf). In addition while deriving this set, we show how many other popular functional and effective connectivity methods are actually simplifications of these equations. We discuss implications of these connections for the practice of using one method to simulate data for another method. After mathematically connecting the three effective connectivity methods, simulated fMRI data with varying numbers of regions and task conditions is generated from the common equation. This simulated data explicitly contains the type of the connectivity that the three models were intended to identify. Each method is applied to the simulated data sets and the accuracy of parameter identification is analyzed. All methods perform above chance levels at identifying correct connectivity parameters. The sLDSf method was superior in parameter estimation accuracy to both DCM and MAR for all types of comparisons. PMID:23717258

Cognitive-Motor Interference during Walking in Older Adults with Probable Mild Cognitive Impairment

PubMed Central

Klotzbier, Thomas J.; Schott, Nadja

2017-01-01

Although several studies have shown that dual-tasking (DT) mobility is impaired in Alzheimer's disease, studies on the effects of DT conditions in probable Mild Cognitive Impairment (pMCI) have not yielded unequivocal results. The objectives of the study were to (1) examine the effect of a concurrent task on a complex walking task in adults with cognitive impairment; and (2) determine whether the effect varied with different difficulty levels of the concurrent task. Furthermore, the study was designed to evaluate the Trail-Walking Test (TWT) as a potential detection tool for MCI. We examined DT performance in 42 young adults (mean age 23.9 ± 1.98), and 43 older adults (mean age 68.2 ± 6.42). The MoCA was used to stratify the subjects into those with and without pMCI. DT was assessed using the TWT: participants completed 5 trials each of walking along a fixed pathway, stepping on targets with increasing sequential numbers (i.e., 1-2-…-15), and increasing sequential numbers and letters (i.e., 1-A-2-B-3-…-8). Motor and cognitive DT effects (DTE) were calculated for each task. ROC curves were used to distinguish younger and healthy older adults from older adults with pMCI. The TWT showed excellent test-retest reliability across all conditions and groups (ICC : 0.83–0.97). SEM% was also low (<11%) as was the MDC95% (<30%). Within the DT conditions, the pMCI group showed significantly longer durations for all tasks regardless of the cognitive load compared to the younger and the healthy older adults. The motor DTEs were greatest for the complex condition in older adults with pMCI more so than in comparison with younger and healthy older adults. ROC analyses confirmed that only the tasks with higher cognitive load could differentiate older adults with pMCI from controls (area under the curve >0.7, p < 0.05). The TWT is a reliable DT mobility measure in people with pMCI. However, the condition with high cognitive load is more sensitive than the condition with low cognitive load in identifying pMCI. The TWT-3 thus could serve as a screening tool for early detection of individuals with pMCI. Future studies need to determine the neural correlates for cognitive-motor interference in older adults with pMCI. PMID:29321738

Cognitive-Motor Interference during Walking in Older Adults with Probable Mild Cognitive Impairment.

PubMed

Klotzbier, Thomas J; Schott, Nadja

2017-01-01

Although several studies have shown that dual-tasking (DT) mobility is impaired in Alzheimer's disease, studies on the effects of DT conditions in probable Mild Cognitive Impairment (pMCI) have not yielded unequivocal results. The objectives of the study were to (1) examine the effect of a concurrent task on a complex walking task in adults with cognitive impairment; and (2) determine whether the effect varied with different difficulty levels of the concurrent task. Furthermore, the study was designed to evaluate the Trail-Walking Test (TWT) as a potential detection tool for MCI. We examined DT performance in 42 young adults (mean age 23.9 ± 1.98), and 43 older adults (mean age 68.2 ± 6.42). The MoCA was used to stratify the subjects into those with and without pMCI. DT was assessed using the TWT: participants completed 5 trials each of walking along a fixed pathway, stepping on targets with increasing sequential numbers (i.e., 1-2-…-15), and increasing sequential numbers and letters (i.e., 1-A-2-B-3-…-8). Motor and cognitive DT effects (DTE) were calculated for each task. ROC curves were used to distinguish younger and healthy older adults from older adults with pMCI. The TWT showed excellent test-retest reliability across all conditions and groups (ICC : 0.83-0.97). SEM% was also low (<11%) as was the MDC95% (<30%). Within the DT conditions, the pMCI group showed significantly longer durations for all tasks regardless of the cognitive load compared to the younger and the healthy older adults. The motor DTEs were greatest for the complex condition in older adults with pMCI more so than in comparison with younger and healthy older adults. ROC analyses confirmed that only the tasks with higher cognitive load could differentiate older adults with pMCI from controls (area under the curve >0.7, p < 0.05). The TWT is a reliable DT mobility measure in people with pMCI. However, the condition with high cognitive load is more sensitive than the condition with low cognitive load in identifying pMCI. The TWT-3 thus could serve as a screening tool for early detection of individuals with pMCI. Future studies need to determine the neural correlates for cognitive-motor interference in older adults with pMCI.

Student Material for Competency-Based Education Curriculum for Licensed Practical Nurse.

ERIC Educational Resources Information Center

Associated Educational Consultants, Inc., Pittsburgh, PA.

This curriculum for licensed practical nurse contains 18 units. Each unit is divided into modules comprised of task or job-related competencies. A student competency sheet (SCS) provided for each task is organized into this format: unit number and name, module letter and name of the group of related tasks, and number and name of task; performance…

The National Shipbuilding Research Program. Application of Industrial Engineering Techniques to Reduce Workers’ Compensation and Environmental Costs

DTIC Science & Technology

1999-10-01

TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Surface Warfare Center CD Code 2230-Design Integration...Tools Bldg 192, Room 128 9500 MacArthur Blvd Bethesda, MD 20817-5700 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S...Implementation of Task 2.4 • Task 7.0 Conduct Workshops • Task 8.0 Final Report To ensure success with the project, the research needed to be performed at the

Inappropriately Applying Natural Number Properties in Rational Number Tasks: Characterizing the Development of the Natural Number Bias through Primary and Secondary Education

ERIC Educational Resources Information Center

van Hoof, Jo; Verschaffel, Lieven; van Dooren, Wim

2015-01-01

The natural number bias is known to explain many difficulties learners have with understanding rational numbers. The research field distinguishes three aspects where natural number properties are sometimes inappropriately applied in rational number tasks: density, size, and operations. The overall goal of this study was to characterize the…

Implicit versus explicit frequency comparisons: two mechanisms of auditory change detection.

PubMed

Demany, Laurent; Semal, Catherine; Pressnitzer, Daniel

2011-04-01

Listeners had to compare, with respect to pitch (frequency), a pure tone (T) to a combination of pure tones presented subsequently (C). The elements of C were either synchronous, and therefore difficult to hear out individually, or asynchronous and therefore easier to hear out individually. In the "present/absent" condition, listeners had to judge if T reappeared in C or not. In the "up/down" condition, the task was to judge if the element of C most similar to T was higher or lower than T. When the elements of C were synchronous, the up/down task was found to be easier than the present/absent task; the converse result was obtained when the elements of C were asynchronous. This provides evidence for a duality of auditory comparisons between tone frequencies: (1) implicit comparisons made by automatic and direction-sensitive "frequency-shift detectors"; (2) explicit comparisons more sensitive to the magnitude of a frequency change than to its direction. Another experiment suggests that although the frequency-shift detectors cannot compare effectively two tones separated by an interfering tone, they are largely insensitive to interfering noise bursts.

Impaired Interlimb Coordination of Voluntary Leg Movements in Poststroke Hemiparesis

PubMed Central

Tseng, Shih-Chiao

2010-01-01

Appropriate interlimb coordination of the lower extremities is particularly important for a variety of functional human motor behaviors such as jumping, kicking a ball, or simply walking. Specific interlimb coordination patterns may be especially impaired after a lesion to the motor system such as stroke, yet this has not been thoroughly examined to date. The purpose of this study was to investigate the motor deficits in individuals with chronic stroke and hemiparesis when performing unilateral versus bilateral inphase versus bilateral antiphase voluntary cyclic ankle movements. We recorded ankle angular trajectories and muscle activity from the dorsiflexors and plantarflexors and compared these between subjects with stroke and a group of healthy age-matched control subjects. Results showed clear abnormalities in both the kinematics and EMG of the stroke subjects, with significant movement degradation during the antiphase task compared with either the unilateral or the inphase task. The abnormalities included prolonged cycle durations, reduced ankle excursions, decreased agonist EMG bursts, and reduced EMG modulation across movement phases. By comparison, the control group showed nearly identical performance across all task conditions. These findings suggest that stroke involving the corticospinal system projection to the leg specifically impairs one or more components of the neural circuitry involved in lower extremity interlimb coordination. The express susceptibility of the antiphase pattern to exaggerated motor deficits could contribute to functional deficits in a number of antiphase leg movement tasks, including walking. PMID:20463199

Geospace Plasma Dynamics Laboratory Annual Task Report (FY11)

DTIC Science & Technology

2012-03-01

Site Contractors: Nagendra Singh, Ph.D., Physicist , 0.5 MY Neil Grossbard, M.S., Mathematician , 0.7 MY Visitors: Publications: Articles in...PhD Project Manager Division Chief, RVB This report is published in the interest of scientific and technical...Annual Task Report (FY11) 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) 5d. PROJECT NUMBER 2311 Daniel Ober 5e. TASK NUMBER

A Voxel-by-Voxel Comparison of Deformable Vector Fields Obtained by Three Deformable Image Registration Algorithms Applied to 4DCT Lung Studies.

PubMed

Fatyga, Mirek; Dogan, Nesrin; Weiss, Elizabeth; Sleeman, William C; Zhang, Baoshe; Lehman, William J; Williamson, Jeffrey F; Wijesooriya, Krishni; Christensen, Gary E

2015-01-01

Commonly used methods of assessing the accuracy of deformable image registration (DIR) rely on image segmentation or landmark selection. These methods are very labor intensive and thus limited to relatively small number of image pairs. The direct voxel-by-voxel comparison can be automated to examine fluctuations in DIR quality on a long series of image pairs. A voxel-by-voxel comparison of three DIR algorithms applied to lung patients is presented. Registrations are compared by comparing volume histograms formed both with individual DIR maps and with a voxel-by-voxel subtraction of the two maps. When two DIR maps agree one concludes that both maps are interchangeable in treatment planning applications, though one cannot conclude that either one agrees with the ground truth. If two DIR maps significantly disagree one concludes that at least one of the maps deviates from the ground truth. We use the method to compare 3 DIR algorithms applied to peak inhale-peak exhale registrations of 4DFBCT data obtained from 13 patients. All three algorithms appear to be nearly equivalent when compared using DICE similarity coefficients. A comparison based on Jacobian volume histograms shows that all three algorithms measure changes in total volume of the lungs with reasonable accuracy, but show large differences in the variance of Jacobian distribution on contoured structures. Analysis of voxel-by-voxel subtraction of DIR maps shows differences between algorithms that exceed a centimeter for some registrations. Deformation maps produced by DIR algorithms must be treated as mathematical approximations of physical tissue deformation that are not self-consistent and may thus be useful only in applications for which they have been specifically validated. The three algorithms tested in this work perform fairly robustly for the task of contour propagation, but produce potentially unreliable results for the task of DVH accumulation or measurement of local volume change. Performance of DIR algorithms varies significantly from one image pair to the next hence validation efforts, which are exhaustive but performed on a small number of image pairs may not reflect the performance of the same algorithm in practical clinical situations. Such efforts should be supplemented by validation based on a longer series of images of clinical quality.

Verbal and action-based measures of kindergartners' SFON and their associations with number-related utterances during picture book reading.

PubMed

Rathé, Sanne; Torbeyns, Joke; De Smedt, Bert; Hannula-Sormunen, Minna M; Verschaffel, Lieven

2017-11-20

Young children's spontaneous focusing on numerosity (SFON) as measured by experimental tasks is related to their mathematics achievement. This association is hypothetically explained by children's self-initiated practice in number recognition during everyday activities. As such, experimentally measured SFON should be associated with SFON exhibited during everyday activities and play. However, prior studies investigating this assumed association provided inconsistent findings. We aimed to address this issue by investigating the association between kindergartners' SFON as measured by two different experimental tasks and the frequency of their number-related utterances during a typical picture book reading activity. Participants were 65 4- to 6-year-olds in kindergarten (before the start of formal education). Kindergartners individually participated in two sessions. First, they completed an action-based SFON Imitation task and a verbal SFON Picture task, with a short visuo-motor task in between. Next, children were invited to spontaneously comment on the pictures of a picture book during a typical picture book reading activity. Results revealed a positive association between children's SFON as measured by the Picture task and the frequency of their number-related utterances during typical picture book reading, but no such association for the Imitation task. Our findings indicate that children with higher SFON as measured by a verbal experimental task also tend to focus more frequently on number during verbal everyday activities, such as picture book reading. In view of the divergent associations between our SFON measures under study with everyday number activities, the current data suggest that SFON may not be a unitary construct and/or might be task-dependent. © 2017 The British Psychological Society.

A study of active learning methods for named entity recognition in clinical text.

PubMed

Chen, Yukun; Lasko, Thomas A; Mei, Qiaozhu; Denny, Joshua C; Xu, Hua

2015-12-01

Named entity recognition (NER), a sequential labeling task, is one of the fundamental tasks for building clinical natural language processing (NLP) systems. Machine learning (ML) based approaches can achieve good performance, but they often require large amounts of annotated samples, which are expensive to build due to the requirement of domain experts in annotation. Active learning (AL), a sample selection approach integrated with supervised ML, aims to minimize the annotation cost while maximizing the performance of ML-based models. In this study, our goal was to develop and evaluate both existing and new AL methods for a clinical NER task to identify concepts of medical problems, treatments, and lab tests from the clinical notes. Using the annotated NER corpus from the 2010 i2b2/VA NLP challenge that contained 349 clinical documents with 20,423 unique sentences, we simulated AL experiments using a number of existing and novel algorithms in three different categories including uncertainty-based, diversity-based, and baseline sampling strategies. They were compared with the passive learning that uses random sampling. Learning curves that plot performance of the NER model against the estimated annotation cost (based on number of sentences or words in the training set) were generated to evaluate different active learning and the passive learning methods and the area under the learning curve (ALC) score was computed. Based on the learning curves of F-measure vs. number of sentences, uncertainty sampling algorithms outperformed all other methods in ALC. Most diversity-based methods also performed better than random sampling in ALC. To achieve an F-measure of 0.80, the best method based on uncertainty sampling could save 66% annotations in sentences, as compared to random sampling. For the learning curves of F-measure vs. number of words, uncertainty sampling methods again outperformed all other methods in ALC. To achieve 0.80 in F-measure, in comparison to random sampling, the best uncertainty based method saved 42% annotations in words. But the best diversity based method reduced only 7% annotation effort. In the simulated setting, AL methods, particularly uncertainty-sampling based approaches, seemed to significantly save annotation cost for the clinical NER task. The actual benefit of active learning in clinical NER should be further evaluated in a real-time setting. Copyright © 2015 Elsevier Inc. All rights reserved.

Online fully automated three-dimensional surface reconstruction of unknown objects

NASA Astrophysics Data System (ADS)

Khalfaoui, Souhaiel; Aigueperse, Antoine; Fougerolle, Yohan; Seulin, Ralph; Fofi, David

2015-04-01

This paper presents a novel scheme for automatic and intelligent 3D digitization using robotic cells. The advantage of our procedure is that it is generic since it is not performed for a specific scanning technology. Moreover, it is not dependent on the methods used to perform the tasks associated with each elementary process. The comparison of results between manual and automatic scanning of complex objects shows that our digitization strategy is very efficient and faster than trained experts. The 3D models of the different objects are obtained with a strongly reduced number of acquisitions while moving efficiently the ranging device.

A preference for mathematical processing outweighs the selectivity for Arabic numbers in the inferior temporal gyrus.

PubMed

Grotheer, Mareike; Jeska, Brianna; Grill-Spector, Kalanit

2018-03-28

A region in the posterior inferior temporal gyrus (ITG), referred to as the number form area (NFA, here ITG-numbers) has been implicated in the visual processing of Arabic numbers. However, it is unknown if this region is specifically involved in the visual encoding of Arabic numbers per se or in mathematical processing more broadly. Using functional magnetic resonance imaging (fMRI) during experiments that systematically vary tasks and stimuli, we find that mathematical processing, not preference to Arabic numbers, consistently drives both mean and distributed responses in the posterior ITG. While we replicated findings of higher responses in ITG-numbers to numbers than other visual stimuli during a 1-back task, this preference to numbers was abolished when participants engaged in mathematical processing. In contrast, an ITG region (ITG-math) that showed higher responses during an adding task vs. other tasks maintained this preference for mathematical processing across a wide range of stimuli including numbers, number/letter morphs, hands, and dice. Analysis of distributed responses across an anatomically-defined posterior ITG expanse further revealed that mathematical task but not Arabic number form can be successfully and consistently decoded from these distributed responses. Together, our findings suggest that the function of neuronal regions in the posterior ITG goes beyond the specific visual processing of Arabic numbers. We hypothesize that they ascribe numerical content to the visual input, irrespective of the format of the stimulus. Copyright © 2018 Elsevier Inc. All rights reserved.

Australian Public Preferences for the Funding of New Health Technologies: A Comparison of Discrete Choice and Profile Case Best-Worst Scaling Methods.

PubMed

Whitty, Jennifer A; Ratcliffe, Julie; Chen, Gang; Scuffham, Paul A

2014-07-01

Ethical, economic, political, and legitimacy arguments support the consideration of public preferences in health technology decision making. The objective was to assess public preferences for funding new health technologies and to compare a profile case best-worst scaling (BWS) and traditional discrete choice experiment (DCE) method. An online survey consisting of a DCE and BWS task was completed by 930 adults recruited via an Internet panel. Respondents traded between 7 technology attributes. Participation quotas broadly reflected the population of Queensland, Australia, by gender and age. Choice data were analyzed using a generalized multinomial logit model. The findings from both the BWS and DCE were generally consistent in that respondents exhibited stronger preferences for technologies offering prevention or early diagnosis over other benefit types. Respondents also prioritized technologies that benefit younger people, larger numbers of people, those in rural areas, or indigenous Australians; that provide value for money; that have no available alternative; or that upgrade an existing technology. However, the relative preference weights and consequent preference orderings differed between the DCE and BWS models. Further, poor correlation between the DCE and BWS weights was observed. While only a minority of respondents reported difficulty completing either task (22.2% DCE, 31.9% BWS), the majority (72.6%) preferred the DCE over BWS task. This study provides reassurance that many criteria routinely used for technology decision making are considered to be relevant by the public. The findings clearly indicate the perceived importance of prevention and early diagnosis. The dissimilarity observed between DCE and profile case BWS weights is contrary to the findings of previous comparisons and raises uncertainty regarding the comparative merits of these stated preference methods in a priority-setting context. © The Author(s) 2014.

Lateralized effects of categorical and coordinate spatial processing of component parts on the recognition of 3D non-nameable objects.

PubMed

Saneyoshi, Ayako; Michimata, Chikashi

2009-12-01

Participants performed two object-matching tasks for novel, non-nameable objects consisting of geons. For each original stimulus, two transformations were applied to create comparison stimuli. In the categorical transformation, a geon connected to geon A was moved to geon B. In the coordinate transformation, a geon connected to geon A was moved to a different position on geon A. The Categorical task consisted of the original and the categorically transformed objects. The Coordinate task consisted of the original and the coordinately transformed objects. The original object was presented to the central visual field, followed by a comparison object presented to the right or left visual half-fields (RVF and LVF). The results showed an RVF advantage for the Categorical task and an LVF advantage for the Coordinate task. The possibility that categorical and coordinate spatial processing subsystems would be basic computational elements for between- and within-category object recognition was discussed.

Altered neural activation during prepotent response inhibition in breast cancer survivors treated with chemotherapy: an fMRI study.

PubMed

Kam, Julia W Y; Boyd, Lara A; Hsu, Chun L; Liu-Ambrose, Teresa; Handy, Todd C; Lim, Howard J; Hayden, Sherri; Campbell, Kristin L

2016-09-01

While impairments in executive functions have been reported in breast cancer survivors (BCS) who have undergone adjuvant chemotherapy, only a limited number of functional neuroimaging studies have associated alterations in cerebral activity with executive functions deficits in BCS. Using fMRI, the current study assessed the neural basis underlying a specific facet of executive function, namely prepotent response inhibition. 12 BCS who self-reported cognitive problems up to 3 years following cancer treatment and 12 female healthy comparisons (HC) performed the Stroop task. We compared their neural activation between the incongruent and neutral experimental conditions. Relative to the HC group, BCS showed lower blood-oxygen level dependent signal in several frontal regions, including the anterior cingulate cortex, a region critical for response inhibition. Our data indicates reduced neural activation in BCS during a prepotent response inhibition task, providing support for the prevailing notion of neural alterations observed in BCS treated with chemotherapy.

Contingent capture and inhibition of return: a comparison of mechanisms.

PubMed

Prinzmetal, William; Taylor, Jordan A; Myers, Loretta Barry; Nguyen-Espino, Jacqueline

2011-09-01

We investigated the cause(s) of two effects associated with involuntary attention in the spatial cueing task: contingent capture and inhibition of return (IOR). Previously, we found that there were two mechanisms of involuntary attention in this task: (1) a (serial) search mechanism that predicts a larger cueing effect in reaction time with more display locations and (2) a decision (threshold) mechanism that predicts a smaller cueing effect with more display locations (Prinzmetal et al. 2010). In the present study, contingent capture and IOR had completely different patterns of results when we manipulated the number of display locations and the presence of distractors. Contingent capture was best described by a search model, whereas the inhibition of return was best described by a decision model. Furthermore, we fit a linear ballistic accumulator model to the results and IOR was accounted for by a change of threshold, whereas the results from contingent capture experiments could not be fit with a change of threshold and were better fit by a search model.

[Family practitioners in Switzerland by 2030: which roles for medical task delegation?].

PubMed

Jaccard Ruedin, Hélène; Seematter-Bagnoud, Laurence; Roth, Maik; Junod, Julien; Santos-Eggimann, Brigitte

2009-01-01

Due to population aging, by 2030 Switzerland may face a demand of 24 million family practitioner visits, a growth of 13 percent from the 2005 level. This result is based on the assumption that the per capita demand for doctor visits remains what was observed in 2005 by age groups and sex. During the same period, the total number of practitioners may decrease by 14 percent whereas the female proportion of such practitioners may double. These changes may cause a 33 percent decrease in the supply of physician visits to reach only 14 millions. The comparison of the demand and supply of family doctor visits reveals that by 2030, 10 million visits may be unmet which represents 40 percent of the demand. On the supply side, a full scale implementation of task delegation may partially reduce that gap (minus 2 millions). On the demand side, improved health status may bring in a larger decrease in the needs for visits (minus 4 million).

A practical guide for the identification of membrane and plasma membrane proteins in human embryonic stem cells and human embryonal carcinoma cells.

PubMed

Dormeyer, Wilma; van Hoof, Dennis; Mummery, Christine L; Krijgsveld, Jeroen; Heck, Albert J R

2008-10-01

The identification of (plasma) membrane proteins in cells can provide valuable insights into the regulation of their biological processes. Pluripotent cells such as human embryonic stem cells and embryonal carcinoma cells are capable of unlimited self-renewal and share many of the biological mechanisms that regulate proliferation and differentiation. The comparison of their membrane proteomes will help unravel the biological principles of pluripotency, and the identification of biomarker proteins in their plasma membranes is considered a crucial step to fully exploit pluripotent cells for therapeutic purposes. For these tasks, membrane proteomics is the method of choice, but as indicated by the scarce identification of membrane and plasma membrane proteins in global proteomic surveys it is not an easy task. In this minireview, we first describe the general challenges of membrane proteomics. We then review current sample preparation steps and discuss protocols that we found particularly beneficial for the identification of large numbers of (plasma) membrane proteins in human tumour- and embryo-derived stem cells. Our optimized assembled protocol led to the identification of a large number of membrane proteins. However, as the composition of cells and membranes is highly variable we still recommend adapting the sample preparation protocol for each individual system.

A large-scale dataset of single and mixed-source short tandem repeat profiles to inform human identification strategies: PROVEDIt.

PubMed

Alfonse, Lauren E; Garrett, Amanda D; Lun, Desmond S; Duffy, Ken R; Grgicak, Catherine M

2018-01-01

DNA-based human identity testing is conducted by comparison of PCR-amplified polymorphic Short Tandem Repeat (STR) motifs from a known source with the STR profiles obtained from uncertain sources. Samples such as those found at crime scenes often result in signal that is a composite of incomplete STR profiles from an unknown number of unknown contributors, making interpretation an arduous task. To facilitate advancement in STR interpretation challenges we provide over 25,000 multiplex STR profiles produced from one to five known individuals at target levels ranging from one to 160 copies of DNA. The data, generated under 144 laboratory conditions, are classified by total copy number and contributor proportions. For the 70% of samples that were synthetically compromised, we report the level of DNA damage using quantitative and end-point PCR. In addition, we characterize the complexity of the signal by exploring the number of detected alleles in each profile. Copyright © 2017 Elsevier B.V. All rights reserved.

Age-related spatial learning impairment is unrelated to spinophilin immunoreactive spine number and protein levels in rat hippocampus.

PubMed

Calhoun, Michael E; Fletcher, Bonnie R; Yi, Stella; Zentko, Diana C; Gallagher, Michela; Rapp, Peter R

2008-08-01

Age-related impairments in hippocampus-dependent learning and memory tasks are not associated with a loss of hippocampal neurons, but may be related to alterations in synaptic integrity. Here we used stereological techniques to estimate spine number in hippocampal subfields using immunostaining for the spine-associated protein, spinophilin, as a marker. Quantification of the immunoreactive profiles was performed using the optical disector/fractionator technique. Aging was associated with a modest increase in spine number in the molecular layer of the dentate gyrus and CA1 stratum lacunosum-moleculare. By comparison, spinophilin protein levels in the hippocampus, measured by Western blot analysis, failed to differ as a function of age. Neither the morphological nor the protein level data were correlated with spatial learning ability across individual aged rats. The results extend current evidence on synaptic integrity in the aged brain, indicating that a substantial loss of dendritic spines and spinophilin protein in the hippocampus are unlikely to contribute to age-related impairment in spatial learning.

The relationship between lateral differences in tympanic membrane temperature and behavioral impulsivity.

PubMed

Helton, William S

2010-11-01

In this study lateral differences in tympanic membrane temperature (T(Ty)) were explored as a correlate of either impulsive or cautious responding in Go-No-Go tasks. Thirty-two women and men performed two sustained attention to response tasks (Go-No-Go tasks). Those with warmer right in comparison to left tympanic membranes were more cautious, and those with warmer left in comparison to right tympanic membranes were more impulsive. This finding is in line with previous research and theory indicating a hemispheric bias for active and passive behavior. T(Ty) may be a useful addition to the techniques employed by neuropsychologists. Copyright 2010 Elsevier Inc. All rights reserved.

Reactivity to stress and the cognitive components of math disability in grade 1 children.

PubMed

MacKinnon McQuarrie, Maureen A; Siegel, Linda S; Perry, Nancy E; Weinberg, Joanne

2014-01-01

This study investigated the relationship among working memory, processing speed, math performance, and reactivity to stress in 83 Grade 1 children. Specifically, 39 children with math disability (MD) were compared to 44 children who are typically achieving (TA) in mathematics. It is the first study to use a physiological index of stress (salivary cortisol levels) to measure children's reactivity while completing tasks that assess the core components of MD: working memory for numbers, working memory for words, digits backward, letter number sequence, digit span forward, processing speed for numbers and words, block rotation, and math tasks. Grade 1 children with MD obtained significantly lower scores on the letter number sequence and quantitative concepts tasks. Higher levels of reactivity significantly predicted poorer performance on the working memory for numbers, working memory for words, and quantitative concepts tasks for Grade 1 children, regardless of math ability. Grade 1 children with MD and higher reactivity had significantly lower scores on the letter number sequence task than the children with MD and low reactivity. The findings suggest that high reactivity impairs performance in working memory and math tasks in Grade 1 children, and young children with high reactivity may benefit from interventions aimed at lowering anxiety in stressful situations, which may improve learning. © Hammill Institute on Disabilities 2012.

Reactivity to Stress and the Cognitive Components of Math Disability in Grade 1 Children

PubMed Central

MacKinnon McQuarrie, Maureen A.; Siegel, Linda S.; Perry, Nancy E.; Weinberg, Joanne

2016-01-01

This study investigated the relationship among working memory, processing speed, math performance, and reactivity to stress in 83 Grade 1 children. Specifically, 39 children with math disability (MD) were compared to 44 children who are typically achieving (TA) in mathematics. It is the first study to use a physiological index of stress (salivary cortisol levels) to measure children’s reactivity while completing tasks that assess the core components of MD: working memory for numbers, working memory for words, digits backward, letter number sequence, digit span forward, processing speed for numbers and words, block rotation, and math tasks. Grade 1 children with MD obtained significantly lower scores on the letter number sequence and quantitative concepts tasks. Higher levels of reactivity significantly predicted poorer performance on the working memory for numbers, working memory for words, and quantitative concepts tasks for Grade 1 children, regardless of math ability. Grade 1 children with MD and higher reactivity had significantly lower scores on the letter number sequence task than the children with MD and low reactivity. The findings suggest that high reactivity impairs performance in working memory and math tasks in Grade 1 children, and young children with high reactivity may benefit from interventions aimed at lowering anxiety in stressful situations, which may improve learning. PMID:23124381

Single-digit Arabic numbers do not automatically activate magnitude representations in adults or in children: evidence from the symbolic same-different task.

PubMed

Wong, Becky; Szücs, Dénes

2013-11-01

We investigated whether the mere presentation of single-digit Arabic numbers activates their magnitude representations using a visually-presented symbolic same-different task for 20 adults and 15 children. Participants saw two single-digit Arabic numbers on a screen and judged whether the numbers were the same or different. We examined whether reaction time in this task was primarily driven by (objective or subjective) perceptual similarity, or by the numerical difference between the two digits. We reasoned that, if Arabic numbers automatically activate magnitude representations, a numerical function would best predict reaction time; but if Arabic numbers do not automatically activate magnitude representations, a perceptual function would best predict reaction time. Linear regressions revealed that a perceptual function, specifically, subjective visual similarity, was the best and only significant predictor of reaction time in adults and in children. These data strongly suggest that, in this task, single-digit Arabic numbers do not necessarily automatically activate magnitude representations in adults or in children. As the first study to date to explicitly study the developmental importance of perceptual factors in the symbolic same-different task, we found no significant differences between adults and children in their reliance on perceptual information in this task. Based on our findings, we propose that visual properties may play a key role in symbolic number judgements. © 2013. Published by Elsevier B.V. All rights reserved.

Haptic-Based Perception-Empathy Biofeedback Enhances Postural Motor Learning During High-Cognitive Load Task in Healthy Older Adults

PubMed Central

Yasuda, Kazuhiro; Saichi, Kenta; Iwata, Hiroyasu

2018-01-01

Falls and fall-induced injuries are major global public health problems, and sensory input impairment in older adults results in significant limitations in feedback-type postural control. A haptic-based biofeedback (BF) system can be used for augmenting somatosensory input in older adults, and the application of this BF system can increase the objectivity of the feedback and encourage comparison with that provided by a trainer. Nevertheless, an optimal BF system that focuses on interpersonal feedback for balance training in older adults has not been proposed. Thus, we proposed a haptic-based perception-empathy BF system that provides information regarding the older adult's center-of-foot pressure pattern to the trainee and trainer for refining the motor learning effect. The first objective of this study was to examine the effect of this balance training regimen in healthy older adults performing a postural learning task. Second, this study aimed to determine whether BF training required high cognitive load to clarify its practicability in real-life settings. Twenty older adults were assigned to two groups: BF and control groups. Participants in both groups tried balance training in the single-leg stance while performing a cognitive task (i.e., serial subtraction task). Retention was tested 24 h later. Testing comprised balance performance measures (i.e., 95% confidence ellipse area and mean velocity of sway) and dual-task performance (number of responses and correct answers). Measurements of postural control using a force plate revealed that the stability of the single-leg stance was significantly lower in the BF group than in the control group during the balance task. The BF group retained the improvement in the 95% confidence ellipse area 24 h after the retention test. Results of dual-task performance during the balance task were not different between the two groups. These results confirmed the potential benefit of the proposed balance training regimen in designing successful motor learning programs for preventing falls in older adults. PMID:29868597

Haptic-Based Perception-Empathy Biofeedback Enhances Postural Motor Learning During High-Cognitive Load Task in Healthy Older Adults.

PubMed

Yasuda, Kazuhiro; Saichi, Kenta; Iwata, Hiroyasu

2018-01-01

Falls and fall-induced injuries are major global public health problems, and sensory input impairment in older adults results in significant limitations in feedback-type postural control. A haptic-based biofeedback (BF) system can be used for augmenting somatosensory input in older adults, and the application of this BF system can increase the objectivity of the feedback and encourage comparison with that provided by a trainer. Nevertheless, an optimal BF system that focuses on interpersonal feedback for balance training in older adults has not been proposed. Thus, we proposed a haptic-based perception-empathy BF system that provides information regarding the older adult's center-of-foot pressure pattern to the trainee and trainer for refining the motor learning effect. The first objective of this study was to examine the effect of this balance training regimen in healthy older adults performing a postural learning task. Second, this study aimed to determine whether BF training required high cognitive load to clarify its practicability in real-life settings. Twenty older adults were assigned to two groups: BF and control groups. Participants in both groups tried balance training in the single-leg stance while performing a cognitive task (i.e., serial subtraction task). Retention was tested 24 h later. Testing comprised balance performance measures (i.e., 95% confidence ellipse area and mean velocity of sway) and dual-task performance (number of responses and correct answers). Measurements of postural control using a force plate revealed that the stability of the single-leg stance was significantly lower in the BF group than in the control group during the balance task. The BF group retained the improvement in the 95% confidence ellipse area 24 h after the retention test. Results of dual-task performance during the balance task were not different between the two groups. These results confirmed the potential benefit of the proposed balance training regimen in designing successful motor learning programs for preventing falls in older adults.

Validation of the da Vinci Surgical Skill Simulator across three surgical disciplines: A pilot study

PubMed Central

Alzahrani, Tarek; Haddad, Richard; Alkhayal, Abdullah; Delisle, Josée; Drudi, Laura; Gotlieb, Walter; Fraser, Shannon; Bergman, Simon; Bladou, Frank; Andonian, Sero; Anidjar, Maurice

2013-01-01

Objective: In this paper, we evaluate face, content and construct validity of the da Vinci Surgical Skills Simulator (dVSSS) across 3 surgical disciplines. Methods: In total, 48 participants from urology, gynecology and general surgery participated in the study as novices (0 robotic cases performed), intermediates (1–74) or experts (≥75). Each participant completed 9 tasks (Peg board level 2, match board level 2, needle targeting, ring and rail level 2, dots and needles level 1, suture sponge level 2, energy dissection level 1, ring walk level 3 and tubes). The Mimic Technologies software scored each task from 0 (worst) to 100 (best) using several predetermined metrics. Face and content validity were evaluated by a questionnaire administered after task completion. Wilcoxon test was used to perform pair wise comparisons. Results: The expert group comprised of 6 attending surgeons. The intermediate group included 4 attending surgeons, 3 fellows and 5 residents. The novices included 1 attending surgeon, 1 fellow, 13 residents, 13 medical students and 2 research assistants. The median number of robotic cases performed by experts and intermediates were 250 and 9, respectively. The median overall realistic score (face validity) was 8/10. Experts rated the usefulness of the simulator as a training tool for residents (content validity) as 8.5/10. For construct validity, experts outperformed novices in all 9 tasks (p < 0.05). Intermediates outperformed novices in 7 of 9 tasks (p < 0.05); there were no significant differences in the energy dissection and ring walk tasks. Finally, experts scored significantly better than intermediates in only 3 of 9 tasks (matchboard, dots and needles and energy dissection) (p < 0.05). Conclusions: This study confirms the face, content and construct validities of the dVSSS across urology, gynecology and general surgery. Larger sample size and more complex tasks are needed to further differentiate intermediates from experts. PMID:23914275

The smartphone and the driver's cognitive workload: A comparison of Apple, Google, and Microsoft's intelligent personal assistants.

PubMed

Strayer, David L; Cooper, Joel M; Turrill, Jonna; Coleman, James R; Hopman, Rachel J

2017-06-01

The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple's Siri , Google's Google Now for Android phones, and Microsoft's Cortana ) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive workload of drivers when they used the voice-based features of each smartphone to place a call, select music, or send text messages. Cognitive workload was derived from primary task performance through video analysis, secondary-task performance using the Detection Response Task (DRT), and subjective mental workload. We found that workload was significantly higher than that measured in the single-task drive. There were also systematic differences between the smartphones: The Google system placed lower cognitive demands on the driver than the Apple and Microsoft systems, which did not differ. Video analysis revealed that the difference in mental workload between the smartphones was associated with the number of system errors, the time to complete an action, and the complexity and intuitiveness of the devices. Finally, surprisingly high levels of cognitive workload were observed when drivers were interacting with the devices: "on-task" workload measures did not systematically differ from that associated with a mentally demanding Operation Span (OSPAN) task. The analysis also found residual costs associated using each of the smartphones that took a significant time to dissipate. The data suggest that caution is warranted in the use of smartphone voice-based technology in the vehicle because of the high levels of cognitive workload associated with these interactions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Order of stimulus presentation influences children's acquisition in receptive identification tasks.

PubMed

Petursdottir, Anna Ingeborg; Aguilar, Gabriella

2016-03-01

Receptive identification is usually taught in matching-to-sample format, which entails the presentation of an auditory sample stimulus and several visual comparison stimuli in each trial. Conflicting recommendations exist regarding the order of stimulus presentation in matching-to-sample trials. The purpose of this study was to compare acquisition in receptive identification tasks under 2 conditions: when the sample was presented before the comparisons (sample first) and when the comparisons were presented before the sample (comparison first). Participants included 4 typically developing kindergarten-age boys. Stimuli, which included birds and flags, were presented on a computer screen. Acquisition in the 2 conditions was compared in an adapted alternating-treatments design combined with a multiple baseline design across stimulus sets. All participants took fewer trials to meet the mastery criterion in the sample-first condition than in the comparison-first condition. © 2015 Society for the Experimental Analysis of Behavior.

Does visual working memory represent the predicted locations of future target objects? An event-related brain potential study.

PubMed

Grubert, Anna; Eimer, Martin

2015-11-11

During the maintenance of task-relevant objects in visual working memory, the contralateral delay activity (CDA) is elicited over the hemisphere opposite to the visual field where these objects are presented. The presence of this lateralised CDA component demonstrates the existence of position-dependent object representations in working memory. We employed a change detection task to investigate whether the represented object locations in visual working memory are shifted in preparation for the known location of upcoming comparison stimuli. On each trial, bilateral memory displays were followed after a delay period by bilateral test displays. Participants had to encode and maintain three visual objects on one side of the memory display, and to judge whether they were identical or different to three objects in the test display. Task-relevant memory and test stimuli were located in the same visual hemifield in the no-shift task, and on opposite sides in the horizontal shift task. CDA components of similar size were triggered contralateral to the memorized objects in both tasks. The absence of a polarity reversal of the CDA in the horizontal shift task demonstrated that there was no preparatory shift of memorized object location towards the side of the upcoming comparison stimuli. These results suggest that visual working memory represents the locations of visual objects during encoding, and that the matching of memorized and test objects at different locations is based on a comparison process that can bridge spatial translations between these objects. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2014 Elsevier B.V. All rights reserved.

A Comparison of Self-Monitoring with and without Reinforcement to Improve On-Task Classroom Behavior

ERIC Educational Resources Information Center

Davis, Tonya N.; Dacus, Sharon; Bankhead, Jenna; Haupert, Megan; Fuentes, Lisa; Zoch, Tamara; Kang, Soyeon; Attai, Shanna; Lang, Russell

2014-01-01

In this study we analyzed the effects of a self-monitoring and self-monitoring plus reinforcement intervention on classroom behavior. A typically-developing high school student demonstrating difficulty staying on-task during classroom instruction was observed in three classroom settings associated with high levels of off-task behavior. During…

How Does Sam Feel?: Children's Labelling and Drawing of Basic Emotions

ERIC Educational Resources Information Center

Brechet, Claire; Baldy, Rene; Picard, Delphine

2009-01-01

This study compares the ability of children aged from 6 to 11 to freely produce emotional labels based on detailed scenarios (labelling task), and their ability to depict basic emotions in their human figure drawing (subsequent drawing task). This comparison assesses the relevance of the use of a human figure drawing task in order to test…

Multi-optimization Criteria-based Robot Behavioral Adaptability and Motion Planning

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

Pin, Francois G.

2002-06-01

Robotic tasks are typically defined in Task Space (e.g., the 3-D World), whereas robots are controlled in Joint Space (motors). The transformation from Task Space to Joint Space must consider the task objectives (e.g., high precision, strength optimization, torque optimization), the task constraints (e.g., obstacles, joint limits, non-holonomic constraints, contact or tool task constraints), and the robot kinematics configuration (e.g., tools, type of joints, mobile platform, manipulator, modular additions, locked joints). Commercially available robots are optimized for a specific set of tasks, objectives and constraints and, therefore, their control codes are extremely specific to a particular set of conditions. Thus,more » there exist a multiplicity of codes, each handling a particular set of conditions, but none suitable for use on robots with widely varying tasks, objectives, constraints, or environments. On the other hand, most DOE missions and tasks are typically ''batches of one''. Attempting to use commercial codes for such work requires significant personnel and schedule costs for re-programming or adding code to the robots whenever a change in task objective, robot configuration, number and type of constraint, etc. occurs. The objective of our project is to develop a ''generic code'' to implement this Task-space to Joint-Space transformation that would allow robot behavior adaptation, in real time (at loop rate), to changes in task objectives, number and type of constraints, modes of controls, kinematics configuration (e.g., new tools, added module). Our specific goal is to develop a single code for the general solution of under-specified systems of algebraic equations that is suitable for solving the inverse kinematics of robots, is useable for all types of robots (mobile robots, manipulators, mobile manipulators, etc.) with no limitation on the number of joints and the number of controlled Task-Space variables, can adapt to real time changes in number and type of constraints and in task objectives, and can adapt to changes in kinematics configurations (change of module, change of tool, joint failure adaptation, etc.).« less

Numerical magnitude processing in children with mild intellectual disabilities.

PubMed

Brankaer, Carmen; Ghesquière, Pol; De Smedt, Bert

2011-01-01

The present study investigated numerical magnitude processing in children with mild intellectual disabilities (MID) and examined whether these children have difficulties in the ability to represent numerical magnitudes and/or difficulties in the ability to access numerical magnitudes from formal symbols. We compared the performance of 26 children with MID on a symbolic (digits) and a non-symbolic (dot-arrays) comparison task with the performance of two control groups of typically developing children: one group matched on chronological age and one group matched on mathematical ability level. Findings revealed that children with MID performed more poorly than their typically developing chronological age-matched peers on both the symbolic and non-symbolic comparison tasks, while their performance did not substantially differ from the ability-matched control group. These findings suggest that the development of numerical magnitude representation in children with MID is marked by a delay. This performance pattern was observed for both symbolic and non-symbolic comparison tasks, although difficulties on the former task were more prominent. Interventions in children with MID should therefore foster both the development of magnitude representations and the connections between symbols and the magnitudes they represent. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comparison of inhibition in two timed reaction tasks: the color and emotion Stroop tasks.

PubMed

Cothran, D Lisa; Larsen, Randy

2008-07-01

The authors examined the cross-task consistency of the ability to inhibit the processing of irrelevant information. They compared interference scores on 2 widely used inhibition tasks and found that color word Stroop interference scores correlated with emotion word Stroop interference scores. An examination of physiological reactivity showed that, in general, the color Stroop was more arousing than was the emotion Stroop, most likely due to increased response conflict.

Using Cognitive Task Analysis and Eye Tracking to Understand Imagery Analysis

DTIC Science & Technology

2006-01-01

Using Cognitive Task Analysis and Eye Tracking to Understand Imagery Analysis Laura Kurland, Abigail Gertner, Tom Bartee, Michael Chisholm and...have used these to study the analysts search behavior in detail. 2 EXPERIMENT Using a Cognitive Task Analysis (CTA) framework for knowledge...TITLE AND SUBTITLE Using Cognitive Task Analysis and Eye Tracking to Understand Imagery Analysis 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

Measurement and Modification of Sensorimotor System Function during Visual-Motor Performance

DTIC Science & Technology

1984-04-01

end four video games , were tested on each of six adult subjects. Ewdiuat ion of these tasks as well as EEG correlates of performance led to the...significance in each comparison. RESULTS A. Comparison of Video Game Tasks: In evaluating the four video games tested we considered their structure, ease of... video games tested. In all but the missile dodging game good performarice was associated with an increase in power at 4-7 Hz and to some extent in the

High Velocity Jet Noise Source Location and Reduction. Task 2. Theoretical Developments and Basic Experiments.

DTIC Science & Technology

1978-05-01

Measured Flight Effect for J85/ Aerotrain Conical Nozzle, 400 ft Sideline. 360 4-149. Comparison of Predicted and Measured Flight Velocity Exponent m for J85... Aerotrain Conical Nozzle. 362 4-150. Comparison of Measured and Predicted Flight Noise Spectra for J85/ Aerotrain Conical Nozzle, V = 2200 fps, 400 ft...Bertin Aerotrain simulated flight noise results which were obtained by Clapper, et al.( 72) in Task 4 of this program. Fig- ure 4-148 shows the

On the origins of logarithmic number-to-position mapping.

PubMed

Dotan, Dror; Dehaene, Stanislas

2016-11-01

The number-to-position task, in which children and adults are asked to place numbers on a spatial number line, has become a classic measure of number comprehension. We present a detailed experimental and theoretical dissection of the processing stages that underlie this task. We used a continuous finger-tracking technique, which provides detailed information about the time course of processing stages. When adults map the position of 2-digit numbers onto a line, their final mapping is essentially linear, but intermediate finger location show a transient logarithmic mapping. We identify the origins of this log effect: Small numbers are processed faster than large numbers, so the finger deviates toward the target position earlier for small numbers than for large numbers. When the trajectories are aligned on the finger deviation onset, the log effect disappears. The small-number advantage and the log effect are enhanced in dual-task setting and are further enhanced when the delay between the 2 tasks is shortened, suggesting that these effects originate from a central stage of quantification and decision making. We also report cases of logarithmic mapping-by children and by a brain-injured individual-which cannot be explained by faster responding to small numbers. We show that these findings are captured by an ideal-observer model of the number-to-position mapping task, comprising 3 distinct stages: a quantification stage, whose duration is influenced by both exact and approximate representations of numerical quantity; a Bayesian accumulation-of-evidence stage, leading to a decision about the target location; and a pointing stage. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Approximate number word knowledge before the cardinal principle.

PubMed

Gunderson, Elizabeth A; Spaepen, Elizabet; Levine, Susan C

2015-02-01

Approximate number word knowledge-understanding the relation between the count words and the approximate magnitudes of sets-is a critical piece of knowledge that predicts later math achievement. However, researchers disagree about when children first show evidence of approximate number word knowledge-before, or only after, they have learned the cardinal principle. In two studies, children who had not yet learned the cardinal principle (subset-knowers) produced sets in response to number words (verbal comprehension task) and produced number words in response to set sizes (verbal production task). As evidence of approximate number word knowledge, we examined whether children's numerical responses increased with increasing numerosity of the stimulus. In Study 1, subset-knowers (ages 3.0-4.2 years) showed approximate number word knowledge above their knower-level on both tasks, but this effect did not extend to numbers above 4. In Study 2, we collected data from a broader age range of subset-knowers (ages 3.1-5.6 years). In this sample, children showed approximate number word knowledge on the verbal production task even when only examining set sizes above 4. Across studies, children's age predicted approximate number word knowledge (above 4) on the verbal production task when controlling for their knower-level, study (1 or 2), and parents' education, none of which predicted approximation ability. Thus, children can develop approximate knowledge of number words up to 10 before learning the cardinal principle. Furthermore, approximate number word knowledge increases with age and might not be closely related to the development of exact number word knowledge. Copyright © 2014 Elsevier Inc. All rights reserved.

Brain circuitries involved in emotional interference task in major depression disorder.

PubMed

Chechko, Natalia; Augustin, Marc; Zvyagintsev, Michael; Schneider, Frank; Habel, Ute; Kellermann, Thilo

2013-07-01

Emotional and non-emotional Stroop are frequently applied to study major depressive disorder (MDD). The versions of emotional Stroop used in previous studies were not, unlike the ones employed in the present study, based on semantic incongruence, making it difficult to compare the tasks. We used functional magnetic resonance imaging (fMRI) to study the neural and behavioral responses of 18 healthy subjects and 18 subjects with MDD to emotional and non-emotional word-face Stroop tasks based on semantic incompatibility between targets and distractors. In both groups, the distractors triggered significant amounts of interference conflict. A between-groups comparison revealed hypoactivation in MDD during emotional task in areas supporting conflict resolution (lateral prefrontal cortex, parietal and extrastriate cortices) paralleled by increased response in the right amygdala. Response in the amygdala, however, did not vary between conflicting and non-conflicting trials. While in the emotional (compared to non-emotional) task healthy controls showed considerably stronger involvement of networks related to conflict resolution, in patients, the processing differences between the two conflict types were negligible. The patients group was inhomogeneous in terms of medication and clinical characteristics. The number of female participants was higher, due to which gender effects could not be studied or excluded. Whilst healthy controls seemed able to adjust the involvement of the network supporting conflict resolution based on conflict demand, patients appeared to lack this capability. The reduced cortical involvement coupled with increased response of limbic structures might underlie the maladjustment vis-à-vis new demands in depressed mood. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of Yoga practice on reducing cognitive-motor interference for improving dynamic balance control in healthy adults.

PubMed

Subramaniam, Savitha; Bhatt, Tanvi

2017-02-01

The purpose of our study was to investigate the effects of Yoga on reducing cognitive-motor interference (CMI) for maintaining balance control during varied balance tasks. Yoga (N=10) and age-similar non-practitioners (N=10) performed three balance tasks including the Limits of Stability test (LOS - Intentional balance), Motor Control test (MCT - Reactive balance), and Sensory Organization Test (SOT -condition 6: inducing both somatosensory and visual conflicts) under single-task (ST) and dual-task (DT, addition of a cognitive working memory task) conditions. The motor performance was assessed by recording the response time (RT) and movement velocity (MV) of the center of pressure (CoP) on LOS test, weight symmetry (WS) of CoP on the MCT test and equilibrium (EQ) of CoP on the SOT test. Cognitive performance was recorded as the number of correct responses enumerated in sitting (ST) and under DT conditions. The Motor cost (MC) and cognitive cost (CC) were computed using the formula ([ST-DT]/ST)*100 for all the variables. Greater cost indicates lower performance under DT versus ST condition. The Yoga group showed a significantly lesser MC for both MCT and SOT tests (p<0.05) in comparison to their counterparts. The CC were significantly lower on LOS and MCT test for the Yoga group (p<0.05). Results suggest that Yoga practice can significantly reduce CMI by improving allocation and utilization of attentional resources for both balance control and executive cognitive functioning; thus resulting in better performance under DT conditions. Copyright © 2016. Published by Elsevier Ltd.

Do children with grapheme-colour synaesthesia show cognitive benefits?

PubMed

Simner, Julia; Bain, Angela E

2018-02-01

Grapheme-colour synaesthesia is characterized by conscious and consistent associations between letters and colours, or between numbers and colours (e.g., synaesthetes might see A as red, 7 as green). Our study explored the development of this condition in a group of randomly sampled child synaesthetes. Two previous studies (Simner & Bain, 2013, Frontiers in Human Neuroscience, 7, 603; Simner, Harrold, Creed, Monro, & Foulkes, 2009, Brain, 132, 57) had screened over 600 primary school children to find the first randomly sampled cohort of child synaesthetes. In this study, we evaluate this cohort to ask whether their synaesthesia is associated with a particular cognitive profile of strengths and/or weaknesses. We tested our child synaesthetes at age 10-11 years in a series of cognitive tests, in comparison with matched controls and baseline norms. One previous study (Green & Goswami, 2008, Cognition, 106, 463) had suggested that child synaesthetes might perform differently to non-synaesthetes in such tasks, although those participants may have been a special type of population independent of their synaesthesia. In our own study of randomly sampled child synaesthetes, we found no significant advantages or disadvantages in a receptive vocabulary test and a memory matrix task. However, we found that synaesthetes demonstrated above-average performance in a processing-speed task and a near-significant advantage in a letter-span task (i.e., memory/recall task of letters). Our findings point to advantages for synaesthetes that go beyond those expected from enhanced coding accounts and we present the first picture of the broader cognitive profile of a randomly sampled population of child synaesthetes. © 2017 The British Psychological Society.

Assessment of methodologies for analysis of the dungeness B accidental aircraft crash risk.

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

LaChance, Jeffrey L.; Hansen, Clifford W.

2010-09-01

The Health and Safety Executive (HSE) has requested Sandia National Laboratories (SNL) to review the aircraft crash methodology for nuclear facilities that are being used in the United Kingdom (UK). The scope of the work included a review of one method utilized in the UK for assessing the potential for accidental airplane crashes into nuclear facilities (Task 1) and a comparison of the UK methodology against similar International Atomic Energy Agency (IAEA), United States (US) Department of Energy (DOE), and the US Nuclear Regulatory Commission (NRC) methods (Task 2). Based on the conclusions from Tasks 1 and 2, an additionalmore » Task 3 would provide an assessment of a site-specific crash frequency for the Dungeness B facility using one of the other methodologies. This report documents the results of Task 2. The comparison of the different methods was performed for the three primary contributors to aircraft crash risk at the Dungeness B site: airfield related crashes, crashes below airways, and background crashes. The methods and data specified in each methodology were compared for each of these risk contributors, differences in the methodologies were identified, and the importance of these differences was qualitatively and quantitatively assessed. The bases for each of the methods and the data used were considered in this assessment process. A comparison of the treatment of the consequences of the aircraft crashes was not included in this assessment because the frequency of crashes into critical structures is currently low based on the existing Dungeness B assessment. Although the comparison found substantial differences between the UK and the three alternative methodologies (IAEA, NRC, and DOE) this assessment concludes that use of any of these alternative methodologies would not change the conclusions reached for the Dungeness B site. Performance of Task 3 is thus not recommended.« less

Symbolic Numerical Distance Effect Does Not Reflect the Difference between Numbers.

PubMed

Krajcsi, Attila; Kojouharova, Petia

2017-01-01

In a comparison task, the larger the distance between the two numbers to be compared, the better the performance-a phenomenon termed as the numerical distance effect. According to the dominant explanation, the distance effect is rooted in a noisy representation, and performance is proportional to the size of the overlap between the noisy representations of the two values. According to alternative explanations, the distance effect may be rooted in the association between the numbers and the small-large categories, and performance is better when the numbers show relatively high differences in their strength of association with the small-large properties. In everyday number use, the value of the numbers and the association between the numbers and the small-large categories strongly correlate; thus, the two explanations have the same predictions for the distance effect. To dissociate the two potential sources of the distance effect, in the present study, participants learned new artificial number digits only for the values between 1 and 3, and between 7 and 9, thus, leaving out the numbers between 4 and 6. It was found that the omitted number range (the distance between 3 and 7) was considered in the distance effect as 1, and not as 4, suggesting that the distance effect does not follow the values of the numbers predicted by the dominant explanation, but it follows the small-large property association predicted by the alternative explanations.

Embedding Task-Based Neural Models into a Connectome-Based Model of the Cerebral Cortex.

PubMed

Ulloa, Antonio; Horwitz, Barry

2016-01-01

A number of recent efforts have used large-scale, biologically realistic, neural models to help understand the neural basis for the patterns of activity observed in both resting state and task-related functional neural imaging data. An example of the former is The Virtual Brain (TVB) software platform, which allows one to apply large-scale neural modeling in a whole brain framework. TVB provides a set of structural connectomes of the human cerebral cortex, a collection of neural processing units for each connectome node, and various forward models that can convert simulated neural activity into a variety of functional brain imaging signals. In this paper, we demonstrate how to embed a previously or newly constructed task-based large-scale neural model into the TVB platform. We tested our method on a previously constructed large-scale neural model (LSNM) of visual object processing that consisted of interconnected neural populations that represent, primary and secondary visual, inferotemporal, and prefrontal cortex. Some neural elements in the original model were "non-task-specific" (NS) neurons that served as noise generators to "task-specific" neurons that processed shapes during a delayed match-to-sample (DMS) task. We replaced the NS neurons with an anatomical TVB connectome model of the cerebral cortex comprising 998 regions of interest interconnected by white matter fiber tract weights. We embedded our LSNM of visual object processing into corresponding nodes within the TVB connectome. Reciprocal connections between TVB nodes and our task-based modules were included in this framework. We ran visual object processing simulations and showed that the TVB simulator successfully replaced the noise generation originally provided by NS neurons; i.e., the DMS tasks performed with the hybrid LSNM/TVB simulator generated equivalent neural and fMRI activity to that of the original task-based models. Additionally, we found partial agreement between the functional connectivities using the hybrid LSNM/TVB model and the original LSNM. Our framework thus presents a way to embed task-based neural models into the TVB platform, enabling a better comparison between empirical and computational data, which in turn can lead to a better understanding of how interacting neural populations give rise to human cognitive behaviors.

The auditory dynamic attending theory revisited: A closer look at the pitch comparison task.

PubMed

Bauer, Anna-Katharina R; Jaeger, Manuela; Thorne, Jeremy D; Bendixen, Alexandra; Debener, Stefan

2015-11-11

The dynamic attending theory as originally proposed by Jones, 1976. Psychol. Rev. 83(5), 323-355 posits that tone sequences presented at a regular rhythm entrain attentional oscillations and thereby facilitate the processing of sounds presented in phase with this rhythm. The increased interest in neural correlates of dynamic attending requires robust behavioral indicators of the phenomenon. Here we aimed to replicate and complement the most prominent experimental implementation of dynamic attending (Jones et al., 2002. Psychol. Sci. 13(4), 313-319). The paradigm uses a pitch comparison task in which two tones, the initial and the last of a longer series, have to be compared. In-between the two, distractor tones with variable pitch are presented, at a regular pace. A comparison tone presented in phase with the entrained rhythm is hypothesized to lead to better behavioral performance. Aiming for a conceptual replication, four different variations of the original paradigm were created which were followed by an exact replication attempt. Across all five experiments, only 40 of the 140 tested participants showed the hypothesized pattern of an inverted U-shaped profile in task accuracy, and the group average effects did not replicate the pattern reported by Jones et al., 2002. Psychol. Sci. 13(4), 313-319 in any of the five experiments. However, clear evidence for a relationship between musicality and overall behavioral performance was found. This study casts doubt on the suitability of the pitch comparison task for demonstrating auditory dynamic attending. We discuss alternative tasks that have been shown to support dynamic attending theory, thus lending themselves more readily to studying its neural correlates. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Effects of metacognitive exercise on the development of scientific reasoning

NASA Astrophysics Data System (ADS)

Pearsall, Susan Helen

1999-12-01

The essence of scientific reasoning is the coordination of theory and evidence. Kuhn (1998) implicates metacognitive skill in reflecting on one's theories, and metastrategic management of inferential strategies involved in their coordination with evidence, as critical to scientific reasoning. The present study investigates how metacognitive exercise may improve children's performance on scientific reasoning tasks. Two groups composed of 50 fifth- and sixth-grade students engaged in a scientific investigation activity over six weekly sessions. Additionally, one group engaged in an activity involving reflection on others' performance on the task, while the comparison group spent equivalent time on an unrelated task. Children in the experimental condition showed significant improvement (relative to those in the comparison condition) in terms of the sequence identified by Kuhn et al. (1995), from entirely theory-based reasoning to the skilled coordination of theory and evidence. This improvement, however, was confined to the beginning levels in the sequence. Specifically, experimental subjects attended to and employed evidence in their reasoning to a greater extent than did comparison subjects, even though their inferences remained largely invalid. Also, experimental subjects showed a marginally significant trend toward greater use of multiple-instance evidence (which, unlike single instance evidence, allowed them to make comparative inferences). On a delayed posttest, children in the experimental condition continued to use evidence to justify their inferences to a significantly greater extent than the comparison group. In contrast, performance increased only slightly on a transfer task and group differences were largely nonsignificant. At the delayed posttest, experimental children's level of performance on the metacognitive activity was compared to their performance on the main task. Results indicated that when children were not consistent on both tasks, performance was superior on the metacognitive task. This finding points to a utilization deficiency. Future research should focus on helping children close the gap between knowing strategies and using them. Like the main findings documenting the benefits of enhancing metacognitive awareness, identification of this gap points to the critical role of metacognitive awareness and understanding in skilled thinking.

Selecting Tasks for Evaluating Human Performance as a Function of Gravity

NASA Technical Reports Server (NTRS)

Norcross, Jason R.; Gernhardt, Michael L.

2011-01-01

A challenge in understanding human performance as a function of gravity is determining which tasks to research. Initial studies began with treadmill walking, which was easy to quantify and control. However, with the development of pressurized rovers, it is less important to optimize human performance for ambulation as pressurized rovers will likely perform gross translation for them. Future crews are likely to spend much of their extravehicular activity (EVA) performing geology, construction,a nd maintenance type tasks. With these types of tasks, people have different performance strategies, and it is often difficult to quantify the task and measure steady-state metabolic rates or perform biomechanical analysis. For many of these types of tasks, subjective feedback may be the only data that can be collected. However, subjective data may not fully support a rigorous scientific comparison of human performance across different gravity levels and suit factors. NASA would benefit from having a wide variety of quantifiable tasks that allow human performance comparison across different conditions. In order to determine which tasks will effectively support scientific studies, many different tasks and data analysis techniques will need to be employed. Many of these tasks and techniques will not be effective, but some will produce quantifiable results that are sensitive enough to show performance differences. One of the primary concerns related to EVA performance is metabolic rate. The higher the metabolic rate, the faster the astronaut will exhaust consumables. The focus of this poster will be on how different tasks affect metabolic rate across different gravity levels.

Learning Radiological Appearances of Diseases: Does Comparison Help?

ERIC Educational Resources Information Center

Kok, Ellen M.; de Bruin, Anique B. H.; Robben, Simon G. F.; van Merrienboer, Jeroen J. G.

2013-01-01

Comparison learning is a promising approach for learning complex real-life visual tasks. When medical students study radiological appearances of diseases, comparison of images showing diseases with images showing no abnormalities could help them learn to discriminate relevant, disease-related information. Medical students studied 12 diseases on…

Exploring the Developmental Changes in Automatic Two-Digit Number Processing

ERIC Educational Resources Information Center

Chan, Winnie Wai Lan; Au, Terry K.; Tang, Joey

2011-01-01

Even when two-digit numbers are irrelevant to the task at hand, adults process them. Do children process numbers automatically, and if so, what kind of information is activated? In a novel dot-number Stroop task, children (Grades 1-5) and adults were shown two different two-digit numbers made up of dots. Participants were asked to select the…

Who can escape the natural number bias in rational number tasks? A study involving students and experts.

PubMed

Obersteiner, Andreas; Hoof, Jo Van; Verschaffel, Lieven; Dooren, Wim Van

2016-08-01

Many learners have difficulties with rational number tasks because they persistently rely on their natural number knowledge, which is not always applicable. Studies show that such a natural number bias can mislead not only children but also educated adults. It is still unclear whether and under what conditions mathematical expertise enables people to be completely unaffected by such a bias on tasks in which people with less expertise are clearly biased. We compared the performance of eighth-grade students and expert mathematicians on the same set of algebraic expression problems that addressed the effect of arithmetic operations (multiplication and division). Using accuracy and response time measures, we found clear evidence for a natural number bias in students but no traces of a bias in experts. The data suggested that whereas students based their answers on their intuitions about natural numbers, expert mathematicians relied on their skilled intuitions about algebraic expressions. We conclude that it is possible for experts to be unaffected by the natural number bias on rational number tasks when they use strategies that do not involve natural numbers. © 2015 The British Psychological Society.

3D vision system assessment

NASA Astrophysics Data System (ADS)

Pezzaniti, J. Larry; Edmondson, Richard; Vaden, Justin; Hyatt, Bryan; Chenault, David B.; Kingston, David; Geulen, Vanilynmae; Newell, Scott; Pettijohn, Brad

2009-02-01

In this paper, we report on the development of a 3D vision system consisting of a flat panel stereoscopic display and auto-converging stereo camera and an assessment of the system's use for robotic driving, manipulation, and surveillance operations. The 3D vision system was integrated onto a Talon Robot and Operator Control Unit (OCU) such that direct comparisons of the performance of a number of test subjects using 2D and 3D vision systems were possible. A number of representative scenarios were developed to determine which tasks benefited most from the added depth perception and to understand when the 3D vision system hindered understanding of the scene. Two tests were conducted at Fort Leonard Wood, MO with noncommissioned officers ranked Staff Sergeant and Sergeant First Class. The scenarios; the test planning, approach and protocols; the data analysis; and the resulting performance assessment of the 3D vision system are reported.

How verbal and spatial manipulation networks contribute to calculation: an fMRI study.

PubMed

Zago, Laure; Petit, Laurent; Turbelin, Marie-Renée; Andersson, Frédéric; Vigneau, Mathieu; Tzourio-Mazoyer, Nathalie

2008-01-01

The manipulation of numbers required during calculation is known to rely on working memory (WM) resources. Here, we investigated the respective contributions of verbal and/or spatial WM manipulation brain networks during the addition of four numbers performed by adults, using functional magnetic resonance imaging (fMRI). Both manipulation and maintenance tasks were proposed with syllables, locations, or two-digit numbers. As compared to their maintenance, numbers manipulation (addition) elicited increased activation within a widespread cortical network including inferior temporal, parietal, and prefrontal regions. Our results demonstrate that mastery of arithmetic calculation requires the cooperation of three WM manipulation systems: an executive manipulation system conjointly recruited by the three manipulation tasks, including the anterior cingulate cortex (ACC), the orbital part of the inferior frontal gyrus, and the caudate nuclei; a left-lateralized, language-related, inferior fronto-temporal system elicited by numbers and syllables manipulation tasks required for retrieval, selection, and association of symbolic information; and a right superior and posterior fronto-parietal system elicited by numbers and locations manipulation tasks for spatial WM and attentional processes. Our results provide new information that the anterior intraparietal sulcus (IPS) is involved in tasks requiring a magnitude processing with symbolic (numbers) and nonsymbolic (locations) stimuli. Furthermore, the specificity of arithmetic processing is mediated by a left-hemispheric specialization of the anterior and posterior parts of the IPS as compared to a spatial task involving magnitude processing with nonsymbolic material.

Early Numerical Competence and Number Line Task Performance in Kindergarteners

ERIC Educational Resources Information Center

Fanari, Rachele; Meloni, Carla; Massidda, Davide

2017-01-01

This work aims to evaluate the relationship between early numerical competence in kindergarteners and their numerical representations as measured by the number line task (NLT). Thirty-four 5-year-old children participated in the study. Children's early performance on symbolic and non-symbolic numerical tasks was considered to determine which was a…

Set size and culture influence children's attention to number.

PubMed

Cantrell, Lisa; Kuwabara, Megumi; Smith, Linda B

2015-03-01

Much research evidences a system in adults and young children for approximately representing quantity. Here we provide evidence that the bias to attend to discrete quantity versus other dimensions may be mediated by set size and culture. Preschool-age English-speaking children in the United States and Japanese-speaking children in Japan were tested in a match-to-sample task where number was pitted against cumulative surface area in both large and small numerical set comparisons. Results showed that children from both cultures were biased to attend to the number of items for small sets. Large set responses also showed a general attention to number when ratio difficulty was easy. However, relative to the responses for small sets, attention to number decreased for both groups; moreover, both U.S. and Japanese children showed a significant bias to attend to total amount for difficult numerical ratio distances, although Japanese children shifted attention to total area at relatively smaller set sizes than U.S. children. These results add to our growing understanding of how quantity is represented and how such representation is influenced by context--both cultural and perceptual. Copyright © 2014 Elsevier Inc. All rights reserved.

Mobile phone use for 5 minutes can cause significant memory impairment in humans.

PubMed

Kalafatakis, F; Bekiaridis-Moschou, D; Gkioka, Eirini; Tsolaki, Magda

2017-01-01

Concerns about the possible adverse health effects of mobile phones (MP) have increased along with the expansion of their use. A number of research papers have tried to address this issue. Although many investigations concluded that MP use does have negative consequences, in terms of cognitive function of the human brain, the results so far have been divisive. A number of studies reported impairment of cognitive function after exposure to mobile phone electromagnetic field (MP EMF), while others observed no effect or improved performance. The variance in the results may be attributed to methodological issues. The present article focuses on possible effects of MP use on cognitive function and more specifically on working memory processes. An emphasis is placed in the lack of a validated tool, a cognitive task, that can produce MP EMF effects on human cognition in a repeatable fashion. Sixty four (64) healthy participants as well as 20 with Mild Cognitive Impairment (MCI) were the experimental group, while 36 healthy individuals were the control group. A computerized list of 10 words was presented and the participants were asked to reproduce it. The words were presented very briefly in order to increase the difficulty and hence the sensitivity of the task. Three measurements were taken for the experimental group: a) before using the MP, b) immediately after using the MP for a duration of 5 minutes, c) 5 minutes after the second measurement with no usage of the MP in between. Three measurements of the memory task were also taken for the control group in the same time intervals with no usage of a MP. The effect of age and gender in the performance of the task was taken into account. Healthy participants of the experimental group performed worst in the memory task after using the MP. While the third measurement (5 minutes after the 2nd measurement) was better than the second (after using the MP), but worse than the first (before using the MP). In contrast for the control group the second measurement was better than the first and the third even better than both previous ones. All differences were statistically significant. The reduction of the performance in the task after using the MP was even higher for the age group of 60-80 years old in comparison with younger age groups, as well as for the individuals with MCI in comparison to healthy participants. Age was significantly negative correlated with performance in the task, while gender showed no significant correlation. MP use has a significant negative impact on working memory performance of human participants. The effect is apparent even for a 5 minute use of the MP. Working memory deficits are greater not only for the 60 years old and above participants but also for individuals with Mild Cognitive Impairment. These results are in agreement with previous studies on animals as well as humans on the effects of MP use on the brain. It is argued that low sensitivity of some of the cognitive tasks used until now and the lack of a validated tool in the form of a cognitive task may account for some of the variability in the literature so far. It is suggested that the experimental paradigm that was used in this study for an increased sensitivity measurement of cognitive function and working memory processes in particular may be used for the display of the effects of MP use on cognitive function and for the development of other tasks sensitive to it. Overall, it is concluded that the development of certain restrictions on MP use is necessary for the protection of the brain health of the users.

Overlooking the obvious: a meta-analytic comparison of digit symbol coding tasks and other cognitive measures in schizophrenia.

PubMed

Dickinson, Dwight; Ramsey, Mary E; Gold, James M

2007-05-01

In focusing on potentially localizable cognitive impairments, the schizophrenia meta-analytic literature has overlooked the largest single impairment: on digit symbol coding tasks. To compare the magnitude of the schizophrenia impairment on coding tasks with impairments on other traditional neuropsychological instruments. MEDLINE and PsycINFO electronic databases and reference lists from identified articles. English-language studies from 1990 to present, comparing performance of patients with schizophrenia and healthy controls on coding tasks and cognitive measures representing at least 2 other cognitive domains. Of 182 studies identified, 40 met all criteria for inclusion in the meta-analysis. Means, standard deviations, and sample sizes were extracted for digit symbol coding and 36 other cognitive variables. In addition, we recorded potential clinical moderator variables, including chronicity/severity, medication status, age, and education, and potential study design moderators, including coding task variant, matching, and study publication date. Main analyses synthesized data from 37 studies comprising 1961 patients with schizophrenia and 1444 comparison subjects. Combination of mean effect sizes across studies by means of a random effects model yielded a weighted mean effect for digit symbol coding of g = -1.57 (95% confidence interval, -1.66 to -1.48). This effect compared with a grand mean effect of g = -0.98 and was significantly larger than effects for widely used measures of episodic memory, executive functioning, and working memory. Moderator variable analyses indicated that clinical and study design differences between studies had little effect on the coding task effect. Comparison with previous meta-analyses suggested that current results were representative of the broader literature. Subsidiary analysis of data from relatives of patients with schizophrenia also suggested prominent coding task impairments in this group. The 5-minute digit symbol coding task, reliable and easy to administer, taps an information processing inefficiency that is a central feature of the cognitive deficit in schizophrenia and deserves systematic investigation.

Validating an Elicited Imitation Task as a Measure of Implicit Knowledge: Comparisons with Other Validation Studies

ERIC Educational Resources Information Center

Spada, Nina; Shiu, Julie Li-Ju; Tomita, Yasuyo

2015-01-01

This study builds on research investigating the construct validity of elicited imitation (EI) as a measure of implicit second language (L2) grammatical knowledge. It differs from previous studies in that the EI task focuses on a single grammatical feature and time on task is strictly controlled. Seventy-three EFL learners and 20 native English…

A Comparison of Heuristic and Human Performance on Open Versions of the Traveling Salesperson Problem

ERIC Educational Resources Information Center

MacGregor, James N.; Chronicle, Edward P.; Ormerod, Thomas C.

2006-01-01

We compared the performance of three heuristics with that of subjects on variants of a well-known combinatorial optimization task, the Traveling Salesperson Problem (TSP). The present task consisted of finding the shortest path through an array of points from one side of the array to the other. Like the standard TSP, the task is computationally…

A Comparison of Reinforcement Learning Models for the Iowa Gambling Task Using Parameter Space Partitioning

ERIC Educational Resources Information Center

Steingroever, Helen; Wetzels, Ruud; Wagenmakers, Eric-Jan

2013-01-01

The Iowa gambling task (IGT) is one of the most popular tasks used to study decision-making deficits in clinical populations. In order to decompose performance on the IGT in its constituent psychological processes, several cognitive models have been proposed (e.g., the Expectancy Valence (EV) and Prospect Valence Learning (PVL) models). Here we…

Processes and Their Products: A Comparison of Task Sequences and Outcome in EAP Writing Classes.

ERIC Educational Resources Information Center

Allison, Desmond; And Others

1995-01-01

A recent study proposed a rational for investigating the effects of mediating tasks upon a summary writing activity for tertiary-level students using English as an educational medium. The tasks in this study involved a group discussion or a reading comprehension exercise, with a third condition providing for immediate access to the text and…

Extending the evaluation of Genia Event task toward knowledge base construction and comparison to Gene Regulation Ontology task

PubMed Central

2015-01-01

Background The third edition of the BioNLP Shared Task was held with the grand theme "knowledge base construction (KB)". The Genia Event (GE) task was re-designed and implemented in light of this theme. For its final report, the participating systems were evaluated from a perspective of annotation. To further explore the grand theme, we extended the evaluation from a perspective of KB construction. Also, the Gene Regulation Ontology (GRO) task was newly introduced in the third edition. The final evaluation of the participating systems resulted in relatively low performance. The reason was attributed to the large size and complex semantic representation of the ontology. To investigate potential benefits of resource exchange between the presumably similar tasks, we measured the overlap between the datasets of the two tasks, and tested whether the dataset for one task can be used to enhance performance on the other. Results We report an extended evaluation on all the participating systems in the GE task, incoporating a KB perspective. For the evaluation, the final submission of each participant was converted to RDF statements, and evaluated using 8 queries that were formulated in SPARQL. The results suggest that the evaluation may be concluded differently between the two different perspectives, annotation vs. KB. We also provide a comparison of the GE and GRO tasks by converting their datasets into each other's format. More than 90% of the GE data could be converted into the GRO task format, while only half of the GRO data could be mapped to the GE task format. The imbalance in conversion indicates that the GRO is a comprehensive extension of the GE task ontology. We further used the converted GRO data as additional training data for the GE task, which helped improve GE task participant system performance. However, the converted GE data did not help GRO task participants, due to overfitting and the ontology gap. PMID:26202680

What keeps family physicians busy in Portugal? A multicentre observational study of work other than direct patient contacts

PubMed Central

Granja, Mónica; Ponte, Carla; Cavadas, Luís Filipe

2014-01-01

Objectives To quantify the time spent by family physicians (FP) on tasks other than direct patient contact, to evaluate job satisfaction, to analyse the association between time spent on tasks and physician characteristics, the association between the number of tasks performed and physician characteristics and the association between time spent on tasks and job satisfaction. Design Cross-sectional, using time-and-motion techniques. Two workdays were documented by direct observation. A significance level of 0.05 was adopted. Setting Multicentric in 104 Portuguese family practices. Participants A convenience sample of FP, with lists of over 1000 patients, teaching senior medical students and first-year family medicine residents in 2012, was obtained. Of the 217 FP invited to participate, 155 completed the study. Main outcomes measured Time spent on tasks other than direct patient contact and on the performance of more than one task simultaneously, the number of direct patient contacts in the office, the number of indirect patient contacts, job satisfaction, demographic and professional characteristics associated with time spent on tasks and the number of different tasks performed, and the association between time spent on tasks and job satisfaction. Results FP (n=155) spent a mean of 143.6 min/day (95% CI 135.2 to 152.0) performing tasks such as prescription refills, teaching, meetings, management and communication with other professionals (33.4% of their workload). FP with larger patient lists spent less time on these tasks (p=0.002). Older FP (p=0.021) and those with larger lists (p=0.011) performed fewer tasks. The mean job satisfaction score was 3.5 (out of 5). No association was found between job satisfaction and time spent on tasks. Conclusions FP spent one-third of their workday in coordinating care, teaching and managing. Time devoted to these tasks decreases with increasing list size and physician age. PMID:24934208

Different Neuroplasticity for Task Targets and Distractors

PubMed Central

Spingath, Elsie Y.; Kang, Hyun Sug; Plummer, Thane; Blake, David T.

2011-01-01

Adult learning-induced sensory cortex plasticity results in enhanced action potential rates in neurons that have the most relevant information for the task, or those that respond strongly to one sensory stimulus but weakly to its comparison stimulus. Current theories suggest this plasticity is caused when target stimulus evoked activity is enhanced by reward signals from neuromodulatory nuclei. Prior work has found evidence suggestive of nonselective enhancement of neural responses, and suppression of responses to task distractors, but the differences in these effects between detection and discrimination have not been directly tested. Using cortical implants, we defined physiological responses in macaque somatosensory cortex during serial, matched, detection and discrimination tasks. Nonselective increases in neural responsiveness were observed during detection learning. Suppression of responses to task distractors was observed during discrimination learning, and this suppression was specific to cortical locations that sampled responses to the task distractor before learning. Changes in receptive field size were measured as the area of skin that had a significant response to a constant magnitude stimulus, and these areal changes paralleled changes in responsiveness. From before detection learning until after discrimination learning, the enduring changes were selective suppression of cortical locations responsive to task distractors, and nonselective enhancement of responsiveness at cortical locations selective for target and control skin sites. A comparison of observations in prior studies with the observed plasticity effects suggests that the non-selective response enhancement and selective suppression suffice to explain known plasticity phenomena in simple spatial tasks. This work suggests that differential responsiveness to task targets and distractors in primary sensory cortex for a simple spatial detection and discrimination task arise from nonselective increases in response over a broad cortical locus that includes the representation of the task target, and selective suppression of responses to the task distractor within this locus. PMID:21297962

Implicit learning in children and adults with Williams syndrome.

PubMed

Don, Audrey J; Schellenberg, E Glenn; Reber, Arthur S; DiGirolamo, Kristen M; Wang, Paul P

2003-01-01

In comparison to explicit learning, implicit learning is hypothesized to be a phylogenetically older form of learning that is important in early developmental processes (e.g., natural language acquisition, socialization)and relatively impervious to individual differences in age and IQ. We examined implicit learning in a group of children and adults (9.49 years of age)with Williams syndrome (WS)and in a comparison group of typically developing individuals matched for chronological age. Participants were tested in an artificial-grammar learning paradigm and in a rotor-pursuit task. For both groups, implicit learning was largely independent of age. Both groups showed evidence of implicit learning but the comparison group outperformed the WS group on both tasks. Performance advantages for the comparison group were no longer significant when group differences in working memory or nonverbal intelligence were held constant.

Item Response Modeling of Paired Comparison and Ranking Data

ERIC Educational Resources Information Center

Maydeu-Olivares, Alberto; Brown, Anna

2010-01-01

The comparative format used in ranking and paired comparisons tasks can significantly reduce the impact of uniform response biases typically associated with rating scales. Thurstone's (1927, 1931) model provides a powerful framework for modeling comparative data such as paired comparisons and rankings. Although Thurstonian models are generally…

Single-digit Arabic numbers do not automatically activate magnitude representations in adults or in children: Evidence from the symbolic same–different task☆

PubMed Central

Wong, Becky; Szücs, Dénes

2013-01-01

We investigated whether the mere presentation of single-digit Arabic numbers activates their magnitude representations using a visually-presented symbolic same–different task for 20 adults and 15 children. Participants saw two single-digit Arabic numbers on a screen and judged whether the numbers were the same or different. We examined whether reaction time in this task was primarily driven by (objective or subjective) perceptual similarity, or by the numerical difference between the two digits. We reasoned that, if Arabic numbers automatically activate magnitude representations, a numerical function would best predict reaction time; but if Arabic numbers do not automatically activate magnitude representations, a perceptual function would best predict reaction time. Linear regressions revealed that a perceptual function, specifically, subjective visual similarity, was the best and only significant predictor of reaction time in adults and in children. These data strongly suggest that, in this task, single-digit Arabic numbers do not necessarily automatically activate magnitude representations in adults or in children. As the first study to date to explicitly study the developmental importance of perceptual factors in the symbolic same–different task, we found no significant differences between adults and children in their reliance on perceptual information in this task. Based on our findings, we propose that visual properties may play a key role in symbolic number judgements. PMID:24076332

48 CFR 1852.232-81 - Contract funding.

Code of Federal Regulations, 2010 CFR

2010-10-01

... allotment is for [Insert applicable item number(s), task(s), or work description] _____ and covers the following estimated period of performance: _____. (b) An additional amount of $______ is obligated under...

The Symbol Grounding Problem Revisited: A Thorough Evaluation of the ANS Mapping Account and the Proposal of an Alternative Account Based on Symbol–Symbol Associations

PubMed Central

Reynvoet, Bert; Sasanguie, Delphine

2016-01-01

Recently, a lot of studies in the domain of numerical cognition have been published demonstrating a robust association between numerical symbol processing and individual differences in mathematics achievement. Because numerical symbols are so important for mathematics achievement, many researchers want to provide an answer on the ‘symbol grounding problem,’ i.e., how does a symbol acquires its numerical meaning? The most popular account, the approximate number system (ANS) mapping account, assumes that a symbol acquires its numerical meaning by being mapped on a non-verbal and ANS. Here, we critically evaluate four arguments that are supposed to support this account, i.e., (1) there is an evolutionary system for approximate number processing, (2) non-symbolic and symbolic number processing show the same behavioral effects, (3) non-symbolic and symbolic numbers activate the same brain regions which are also involved in more advanced calculation and (4) non-symbolic comparison is related to the performance on symbolic mathematics achievement tasks. Based on this evaluation, we conclude that all of these arguments and consequently also the mapping account are questionable. Next we explored less popular alternative, where small numerical symbols are initially mapped on a precise representation and then, in combination with increasing knowledge of the counting list result in an independent and exact symbolic system based on order relations between symbols. We evaluate this account by reviewing evidence on order judgment tasks following the same four arguments. Although further research is necessary, the available evidence so far suggests that this symbol–symbol association account should be considered as a worthy alternative of how symbols acquire their meaning. PMID:27790179

Joint Interagency Task Force-South: The Best Known, Least Understood Interagency Success (INSS Strategic Perspectives, Number 5, June 2011)

DTIC Science & Technology

2011-06-01

CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ...20319 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR...its subcomponents execute their mission by performing research and analysis, publication, conferences, policy support, and outreach. The mission of

Costs of storing colour and complex shape in visual working memory: Insights from pupil size and slow waves.

PubMed

Kursawe, Michael A; Zimmer, Hubert D

2015-06-01

We investigated the impact of perceptual processing demands on visual working memory of coloured complex random polygons during change detection. Processing load was assessed by pupil size (Exp. 1) and additionally slow wave potentials (Exp. 2). Task difficulty was manipulated by presenting different set sizes (1, 2, 4 items) and by making different features (colour, shape, or both) task-relevant. Memory performance in the colour condition was better than in the shape and both condition which did not differ. Pupil dilation and the posterior N1 increased with set size independent of type of feature. In contrast, slow waves and a posterior P2 component showed set size effects but only if shape was task-relevant. In the colour condition slow waves did not vary with set size. We suggest that pupil size and N1 indicates different states of attentional effort corresponding to the number of presented items. In contrast, slow waves reflect processes related to encoding and maintenance strategies. The observation that their potentials vary with the type of feature (simple colour versus complex shape) indicates that perceptual complexity already influences encoding and storage and not only comparison of targets with memory entries at the moment of testing. Copyright © 2015 Elsevier B.V. All rights reserved.

Handedness for Unimanual Grasping in 564 Great Apes: The Effect on Grip Morphology and a Comparison with Hand Use for a Bimanual Coordinated Task

PubMed Central

Meguerditchian, Adrien; Phillips, Kimberley A.; Chapelain, Amandine; Mahovetz, Lindsay M.; Milne, Scott; Stoinski, Tara; Bania, Amanda; Lonsdorf, Elizabeth; Schaeffer, Jennifer; Russell, Jamie; Hopkins, William D.

2015-01-01

A number of factors have been proposed to influence within and between species variation in handedness in non-human primates. In the initial study, we assessed the influence of grip morphology on hand use for simple reaching in a sample of 564 great apes including 49 orangutans Pongo pygmaeus, 66 gorillas Gorilla gorilla, 354 chimpanzees Pan troglodytes and 95 bonobos Pan paniscus. Overall, we found a significant right hand bias for reaching. We also found a significant effect of the grip morphology of hand use. Grasping with the thumb and index finger was more prevalent in the right compared to left hand in all four species. There was no significant sex effect on the patterns of handedness. In a subsample of apes, we also compared consistency in hand use for simple reaching with previously published data on a task that measures handedness for bimanual actions. We found that the ratio of subjects with consistent right compared to left hand use was more prevalent in bonobos, chimpanzees and gorillas but not orangutans. However, for all species, the proportion of subjects with inconsistent hand preferences between the tasks was relatively high suggesting some measures may be more sensitive in assessing handedness than others. PMID:26635693

Iowa Gambling Task with non-clinical participants: effects of using real + virtual cards and additional trials

PubMed Central

Overman, William H.; Pierce, Allison

2013-01-01

Performance on the Iowa Gambling Task (IGT) in clinical populations can be interpreted only in relation to established baseline performance in normal populations. As in all comparisons of assessment tools, the normal baseline must reflect performance under conditions in which subjects can function at their best levels. In this review, we show that a number of variables enhance IGT performance in non-clinical participants. First, optimal performance is produced by having participants turn over real cards while viewing virtual cards on a computer screen. The use of only virtual cards results in significantly lower performance than the combination of real + virtual cards. Secondly, administration of more than 100 trials also enhances performance. When using the real/virtual card procedure, performance is shown to significantly increase from early adolescence through young adulthood. Under these conditions young (mean age 19 years) and older (mean age 59 years) adults perform equally. Females, as a group, score lower than males because females tend to choose cards from high-frequency-of-gain Deck B. Groups of females with high or low gonadal hormones perform equally. Concurrent tasks, e.g., presentation of aromas, decrease performance in males. Age and gender effects are discussed in terms of a dynamic between testosterone and orbital prefrontal cortex. PMID:24376431

Handedness for Unimanual Grasping in 564 Great Apes: The Effect on Grip Morphology and a Comparison with Hand Use for a Bimanual Coordinated Task.

PubMed

Meguerditchian, Adrien; Phillips, Kimberley A; Chapelain, Amandine; Mahovetz, Lindsay M; Milne, Scott; Stoinski, Tara; Bania, Amanda; Lonsdorf, Elizabeth; Schaeffer, Jennifer; Russell, Jamie; Hopkins, William D

2015-01-01

A number of factors have been proposed to influence within and between species variation in handedness in non-human primates. In the initial study, we assessed the influence of grip morphology on hand use for simple reaching in a sample of 564 great apes including 49 orangutans Pongo pygmaeus, 66 gorillas Gorilla gorilla, 354 chimpanzees Pan troglodytes and 95 bonobos Pan paniscus. Overall, we found a significant right hand bias for reaching. We also found a significant effect of the grip morphology of hand use. Grasping with the thumb and index finger was more prevalent in the right compared to left hand in all four species. There was no significant sex effect on the patterns of handedness. In a subsample of apes, we also compared consistency in hand use for simple reaching with previously published data on a task that measures handedness for bimanual actions. We found that the ratio of subjects with consistent right compared to left hand use was more prevalent in bonobos, chimpanzees and gorillas but not orangutans. However, for all species, the proportion of subjects with inconsistent hand preferences between the tasks was relatively high suggesting some measures may be more sensitive in assessing handedness than others.

Route planning with transportation network maps: an eye-tracking study.

PubMed

Grison, Elise; Gyselinck, Valérie; Burkhardt, Jean-Marie; Wiener, Jan Malte

2017-09-01

Planning routes using transportation network maps is a common task that has received little attention in the literature. Here, we present a novel eye-tracking paradigm to investigate psychological processes and mechanisms involved in such a route planning. In the experiment, participants were first presented with an origin and destination pair before we presented them with fictitious public transportation maps. Their task was to find the connecting route that required the minimum number of transfers. Based on participants' gaze behaviour, each trial was split into two phases: (1) the search for origin and destination phase, i.e., the initial phase of the trial until participants gazed at both origin and destination at least once and (2) the route planning and selection phase. Comparisons of other eye-tracking measures between these phases and the time to complete them, which depended on the complexity of the planning task, suggest that these two phases are indeed distinct and supported by different cognitive processes. For example, participants spent more time attending the centre of the map during the initial search phase, before directing their attention to connecting stations, where transitions between lines were possible. Our results provide novel insights into the psychological processes involved in route planning from maps. The findings are discussed in relation to the current theories of route planning.

Executive functions and risky decision-making in patients with opiate dependence.

PubMed

Brand, Matthias; Roth-Bauer, Martina; Driessen, Martin; Markowitsch, Hans J

2008-09-01

Recent evidence suggests that individuals with opiate dependence may have cognitive dysfunctions particularly within the spectrum of executive functioning and emotional processing. Such dysfunctions can also compromise daily decisions associated with risk-taking behaviors. However, it remains unclear whether patients addicted to opiates show impaired decision-making on gambling tasks that specify explicit rules for rewards and punishments and provide information about probabilities associated with different long-term outcomes. In this study, we examined 18 individuals with opiate dependence and 18 healthy comparison subjects, matched for age, gender, and education with the Game of Dice Task (GDT). The GDT is a gambling task with explicit rules for gains and losses and fix winning probabilities. In addition, all subjects completed a neuropsychological test battery that primarily focused on executive functions and a personality questionnaire. On the GDT, patients chose the risky alternatives more frequently than the control group. Patients' GDT performance was related to executive functioning but not to other neuropsychological constructs, personality or dependence specific variables with one exception that is the number of days of abstinence. Thus, patients with opiate dependence demonstrate abnormalities in decision-making that might be neuropsychologically associated with dysfunctional behavior in patients' daily lives. Decision-making and other neuropsychological functioning should be considered in the treatment of opiate dependence.

Understanding linear measurement: A comparison of filipino and new zealand children

NASA Astrophysics Data System (ADS)

Irwin, Kathryn C.; Ell, Fiona R.; Vistro-Yu, Catherine P.

2004-06-01

An understanding of linear measurement depends on principles that include standard unit size, iteration of units, numbering of a unit at its end, and partial units for measuring continuous length. Children may learn these principles at school, for example through experience with informal measurement, or they may learn them through use of measurement in society. This study compared the application of these principles by children aged 8 and 9 from the Philippines and New Zealand. These countries were selected because they have quite different curricula, societal influences and economies. Ninety-one children were interviewed individually on a common set of unusual tasks that were designed to tap underlying principles. Results showed many similarities and some differences between countries. Most tasks requiring visualisation and informal units were done more accurately by New Zealand children. Some tasks involving the use of a conventional ruler were done more accurately by Filipino children. These differences appear to be related to differences in curricula and possibly to differences in societal use of measurement. We suggest that these results, like those of other writers cited, demonstrate the need for extensive work on the underlying concepts in measurement through work on informal measurement and a careful transition between informal and formal measurement.

Sex differences in prefrontal hemodynamic response to mental arithmetic as assessed by near-infrared spectroscopy.

PubMed

Yang, Hongyu; Wang, Ying; Zhou, Zhenyu; Gong, Hui; Luo, Qingming; Wang, Yiwen; Lu, Zuhong

2009-12-01

Sex differences in cognitive tasks have been widely investigated. With brain-imaging techniques, the functions of the brain during the performance of tasks can be examined. Mental arithmetic and near-infrared spectroscopy (NIRS) were used to assess sex differences in prefrontal area activation in a functional brain study. Healthy college students were recruited to perform 2 mental arithmetic tasks. In the first (easy) task, students had to subtract a 1-digit number from a 3-digit number. In the second (difficult) task, they had to subtract a 2-digit number from a 3-digit number. Changes in the concentration of oxygenated hemoglobin (oxy-Hgb) in the prefrontal area during the tasks were measured with NIRS. Thirty students (15 men, 15 women; mean [SD] age: 24.9 [2.2] and 24.3 [2.6] years, respectively) were recruited from Southeast University, Nanjing, China, to participate in the study. The concentration of oxy-Hgb increased during both mental arithmetic tasks (difficult task vs easy task, mean [SD] % arbitrary units: 4.36 [4.38] vs 2.26 [2.82]; F(1,28) = 222.80; P < 0.01). Significant interactions of task x sex (F(1,28) = 82.95), time x sex (F(1,28) = 34.48), task x time (F(1,28) = 222.57), and task x time x sex (F(1,28) = 83.09) were obtained (all, P < 0.01). However, for the 2 tasks, no significant differences between men and women were observed in the mean (SD) response time (men vs women, sec: 3.60 [0.74] vs 3.56 [0.49] for the easy task, 6.55 [0.77] vs 6.44 [0.75] for the difficult task; F(1,28) = 0.67; P = NS) or accuracy rate (men vs women, %: 95.33 [7.40] vs 92.77 [8.80] for the easy task, 62.67 [28.56] vs 54.67 [18.75] for the difficult task; F(1,28) = 0.54; P = NS). Male students showed neural efficiency (less prefrontal activation in subjects with better performance) during the difficult task. In these subjects, sex differences in prefrontal response when performing mental arithmetic were associated with the intensity of the task. Compared with men, women had greater efficiency in task performance (ie, less activation or oxygen consumption for equal performance). Copyright 2009 Excerpta Medica Inc. All rights reserved.

SIGNAL DETECTION BEHAVIOR IN HUMANS AND RATS: A COMPARISON WITH MATCHED TASKS.

EPA Science Inventory

Animal models of human cognitive processes are essential for studying the neurobiological mechanisms of these processes and for developing therapies for intoxication and neurodegenerative diseases. A discrete-trial signal detection task was developed for assessing sustained atten...

Learner-Learner Interaction during Collaborative Pragmatic Tasks: The Role of Cognitive and Pragmatic Task Demands

ERIC Educational Resources Information Center

Kim, YouJin; Taguchi, Naoko

2016-01-01

Previous task complexity studies have suggested that learners produce more negotiation of meaning opportunities during complex tasks than simple tasks (Robinson, 2011). The present study builds on the existing task complexity literature by examining the impact of task complexity and pragmatic situational demands on the number of learning…

Residential Carpentry Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains the occupational duty/task lists for nine occupations in the residential carpentry series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to…

Printing Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains the occupational duty/task lists for 10 occupations in the printing series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide space for…

Diesel Mechanics Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains the occupational duty/task lists for 11 occupations in the diesel mechanics series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide…

Auto Mechanics Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains the occupational duty/task lists for eight occupations in the auto mechanics series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide…

Welding Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains the occupational duty/task lists for six occupations in the welding series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide space for…

Attrition from Web-Based Cognitive Testing: A Repeated Measures Comparison of Gamification Techniques

PubMed Central

Skinner, Andy; Coyle, David; Lawrence, Natalia; Munafo, Marcus

2017-01-01

Background The prospect of assessing cognition longitudinally and remotely is attractive to researchers, health practitioners, and pharmaceutical companies alike. However, such repeated testing regimes place a considerable burden on participants, and with cognitive tasks typically being regarded as effortful and unengaging, these studies may experience high levels of participant attrition. One potential solution is to gamify these tasks to make them more engaging: increasing participant willingness to take part and reducing attrition. However, such an approach must balance task validity with the introduction of entertaining gamelike elements. Objective This study aims to investigate the effects of gamelike features on participant attrition using a between-subjects, longitudinal Web-based testing study. Methods We used three variants of a common cognitive task, the Stop Signal Task (SST), with a single gamelike feature in each: one variant where points were rewarded for performing optimally; another where the task was given a graphical theme; and a third variant, which was a standard SST and served as a control condition. Participants completed four compulsory test sessions over 4 consecutive days before entering a 6-day voluntary testing period where they faced a daily decision to either drop out or continue taking part. Participants were paid for each session they completed. Results A total of 482 participants signed up to take part in the study, with 265 completing the requisite four consecutive test sessions. No evidence of an effect of gamification on attrition was observed. A log-rank test showed no evidence of a difference in dropout rates between task variants (χ22=3.0, P=.22), and a one-way analysis of variance of the mean number of sessions completed per participant in each variant also showed no evidence of a difference (F2,262=1.534, P=.21, partial η2=0.012). Conclusions Our findings raise doubts about the ability of gamification to reduce attrition from longitudinal cognitive testing studies. PMID:29167090

Predictive value of background experiences and visual spatial ability testing on laparoscopic baseline performance among residents entering postgraduate surgical training.

PubMed

Louridas, Marisa; Quinn, Lauren E; Grantcharov, Teodor P

2016-03-01

Emerging evidence suggests that despite dedicated practice, not all surgical trainees have the ability to reach technical competency in minimally invasive techniques. While selecting residents that have the ability to reach technical competence is important, evidence to guide the incorporation of technical ability into selection processes is limited. Therefore, the purpose of the present study was to evaluate whether background experiences and 2D-3D visual spatial test results are predictive of baseline laparoscopic skill for the novice surgical trainee. First-year residents were studied. Demographic data and background surgical and non-surgical experiences were obtained using a questionnaire. Visual spatial ability was evaluated using the PicSOr, cube comparison (CC) and card rotation (CR) tests. Technical skill was assessed using the camera navigation (LCN) task and laparoscopic circle cut (LCC) task. Resident performance on these technical tasks was compared and correlated with the questionnaire and visual spatial findings. Previous experience in observing laparoscopic procedures was associated with significantly better LCN performance, and experience in navigating the laparoscopic camera was associated with significantly better LCC task results. Residents who scored higher on the CC test demonstrated a more accurate LCN path length score (r s(PL) = -0.36, p = 0.03) and angle path (r s(AP) = -0.426, p = 0.01) score when completing the LCN task. No other significant correlations were found between the visual spatial tests (PicSOr, CC or CR) and LCC performance. While identifying selection tests for incoming surgical trainees that predict technical skill performance is appealing, the surrogate markers evaluated correlate with specific metrics of surgical performance related to a single task but do not appear to reliably predict technical performance of different laparoscopic tasks. Predicting the acquisition of technical skills will require the development of a series of evidence-based tests that measure a number of innate abilities as well as their inherent interactions.

Do pet dogs (Canis familiaris) follow ostensive and non-ostensive human gaze to distant space and to objects?

PubMed

Duranton, Charlotte; Range, Friederike; Virányi, Zsófia

2017-07-01

Dogs are renowned for being skilful at using human-given communicative cues such as pointing. Results are contradictory, however, when it comes to dogs' following human gaze, probably due to methodological discrepancies. Here we investigated whether dogs follow human gaze to one of two food locations better than into distant space even after comparable pre-training. In Experiments 1 and 2, the gazing direction of dogs was recorded in a gaze-following into distant space and in an object-choice task where no choice was allowed, in order to allow a direct comparison between tasks, varying the ostensive nature of the gazes. We found that dogs only followed repeated ostensive human gaze into distant space, whereas they followed all gaze cues in the object-choice task. Dogs followed human gaze better in the object-choice task than when there was no obvious target to look at. In Experiment 3, dogs were tested in another object-choice task and were allowed to approach a container. Ostensive cues facilitated the dogs' following gaze with gaze as well as their choices: we found that dogs in the ostensive group chose the indicated container at chance level, whereas they avoided this container in the non-ostensive group. We propose that dogs may perceive the object-choice task as a competition over food and may interpret non-ostensive gaze as an intentional cue that indicates the experimenter's interest in the food location she has looked at. Whether ostensive cues simply mitigate the competitive perception of this situation or they alter how dogs interpret communicative gaze needs further investigation. Our findings also show that following gaze with one's gaze and actually choosing one of the two containers in an object-choice task need to be considered as different variables. The present study clarifies a number of questions related to gaze-following in dogs and adds to a growing body of evidence showing that human ostensive cues can strongly modify dog behaviour.

Simulated thought insertion: Influencing the sense of agency using deception and magic.

PubMed

Olson, Jay A; Landry, Mathieu; Appourchaux, Krystèle; Raz, Amir

2016-07-01

In order to study the feeling of control over decisions, we told 60 participants that a neuroimaging machine could read and influence their thoughts. While inside a mock brain scanner, participants chose arbitrary numbers in two similar tasks. In the Mind-Reading Task, the scanner appeared to guess the participants' numbers; in the Mind-Influencing Task, it appeared to influence their choice of numbers. We predicted that participants would feel less voluntary control over their decisions when they believed that the scanner was influencing their choices. As predicted, participants felt less control and made slower decisions in the Mind-Influencing Task compared to the Mind-Reading Task. A second study replicated these findings. Participants' experience of the ostensible influence varied, with some reporting an unknown source directing them towards specific numbers. This simulated thought insertion paradigm can therefore influence feelings of voluntary control and may help model symptoms of mental disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

Energy-driven scheduling algorithm for nanosatellite energy harvesting maximization

NASA Astrophysics Data System (ADS)

Slongo, L. K.; Martínez, S. V.; Eiterer, B. V. B.; Pereira, T. G.; Bezerra, E. A.; Paiva, K. V.

2018-06-01

The number of tasks that a satellite may execute in orbit is strongly related to the amount of energy its Electrical Power System (EPS) is able to harvest and to store. The manner the stored energy is distributed within the satellite has also a great impact on the CubeSat's overall efficiency. Most CubeSat's EPS do not prioritize energy constraints in their formulation. Unlike that, this work proposes an innovative energy-driven scheduling algorithm based on energy harvesting maximization policy. The energy harvesting circuit is mathematically modeled and the solar panel I-V curves are presented for different temperature and irradiance levels. Considering the models and simulations, the scheduling algorithm is designed to keep solar panels working close to their maximum power point by triggering tasks in the appropriate form. Tasks execution affects battery voltage, which is coupled to the solar panels through a protection circuit. A software based Perturb and Observe strategy allows defining the tasks to be triggered. The scheduling algorithm is tested in FloripaSat, which is an 1U CubeSat. A test apparatus is proposed to emulate solar irradiance variation, considering the satellite movement around the Earth. Tests have been conducted to show that the scheduling algorithm improves the CubeSat energy harvesting capability by 4.48% in a three orbit experiment and up to 8.46% in a single orbit cycle in comparison with the CubeSat operating without the scheduling algorithm.

Target detection, shape discrimination, and signal characteristics of an echolocating false killer whale (Pseudorca crassidens).

PubMed

Brill, R L; Pawloski, J L; Helweg, D A; Au, W W; Moore, P W

1992-09-01

This study demonstrated the ability of a false killer whale (Pseudorca crassidens) to discriminate between two targets and investigated the parameters of the whale's emitted signals for changes related to test conditions. Target detection performance comparable to the bottlenose dolphin's (Tursiops truncatus) has previously been reported for echolocating false killer whales. No other echolocation capabilities have been reported. A false killer whale, naive to conditioned echolocation tasks, was initially trained to detect a cylinder in a "go/no-go" procedure over ranges of 3 to 8 m. The transition from a detection task to a discrimination task was readily achieved by introducing a spherical comparison target. Finally, the cylinder was successfully compared to spheres of two different sizes and target strengths. Multivariate analyses were used to evaluate the parameters of emitted signals. Duncan's multiple range tests showed significant decreases (df = 185, p less than 0.05) in both source level and bandwidth in the transition from detection to discrimination. Analysis of variance revealed a significant decrease in the number of clicks over test conditions [F(5.26) = 5.23, p less than 0.0001]. These data suggest that the whale relied on cues relevant to target shape as well as target strength, that changes in source level and bandwidth were task-related, that the decrease in clicks was associated with learning experience, and that Pseudorca's ability to discriminate shapes using echolocation may be comparable to that of Tursiops truncatus.

Writing abilities in intellectual disabilities: a comparison between Down and Williams syndrome.

PubMed

Varuzza, Cristiana; De Rose, Paola; Vicari, Stefano; Menghini, Deny

2015-02-01

Writing is a complex task that requires the integration of multiple cognitive, linguistic, and motor abilities. Until now, only a few studies investigated writing abilities in individuals with Intellectual Disability (ID). The aim of the present exploratory study was to provide knowledge on the organization of writing in two populations with ID, Down syndrome (DS) and Williams syndrome (WS), trying to disentangle different components of the process. A battery tapping diverse writing demands as low-level transcription skills as well as high-level writing skills was proposed to 13 individuals with WS, 12 individuals with DS and 11 mental-age-matched typically developing (TD) children. Results showed that the two groups with genetic syndromes did not differ from TD in writing a list of objects placed in bedroom, in the number of errors in the text composition, in a text copying task and in kind of errors made. However, in a word dictation task, individuals with DS made more errors than individuals with WS and TD children. In a pseudoword dictation task, both individuals with DS and WS showed more errors than TD children. Our results showed good abilities in individuals with ID in different aspects of writing, involving not only low-level transcription skills but also high-level composition skills. Contrary to the pessimistic view, considering individuals with ID vulnerable for failure, our results indicate that the presence of ID does not prevent the achievement of writing skills. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sustained negative BOLD response in human fMRI finger tapping task.

PubMed

Liu, Yadong; Shen, Hui; Zhou, Zongtan; Hu, Dewen

2011-01-01

In this work, we investigated the sustained negative blood oxygen level-dependent (BOLD) response (sNBR) using functional magnetic resonance imaging during a finger tapping task. We observed that the sNBR for this task was more extensive than has previously been reported. The cortical regions involved in sNBR are divided into the following three groups: frontal, somatosensory and occipital. By investigating the spatial structure, area, amplitude, and dynamics of the sNBR in comparison with those of its positive BOLD response (PBR) counterpart, we made the following observations. First, among the three groups, the somatosensory group contained the greatest number of activated voxels and the fewest deactivated voxels. In addition, the amplitude of the sNBR in this group was the smallest among the three groups. Second, the onset and peak time of the sNBR are both larger than those of the PBR, whereas the falling edge time of the sNBR is less than that of the PBR. Third, the long distance between most sNBR foci and their corresponding PBR foci makes it unlikely that they share the same blood supply artery. Fourth, the couplings between the sNBR and its PBR counterpart are distinct among different regions and thus should be investigated separately. These findings imply that the origin of most sNBR foci in the finger-tapping task is much more likely to be neuronal activity suppression rather than "blood steal."

Task-Based Mirror Therapy Augmenting Motor Recovery in Poststroke Hemiparesis: A Randomized Controlled Trial.

PubMed

Arya, Kamal Narayan; Pandian, Shanta; Kumar, Dharmendra; Puri, Vinod

2015-08-01

To establish the effect of the task-based mirror therapy (TBMT) on the upper limb recovery in stroke. A pilot, randomized, controlled, assessor-blinded trial was conducted in a rehabilitation institute. A convenience sample of 33 poststroke (mean duration, 12.5 months) hemiparetic subjects was randomized into 2 groups (experimental, 17; control, 16). The subjects were allocated to receive either TBMT or standard motor rehabilitation-40 sessions (5/week) for a period of 8 weeks. The TBMT group received movements using various goal-directed tasks and a mirror box. The movements were performed by the less-affected side superimposed on the affected side. The main outcome measures were Brunnstrom recovery stage (BRS) and Fugl-Meyer assessment (FMA)-FMA of upper extremity (FMA-UE), including upper arm (FMA-UA) and wrist-hand (FMA-WH). The TBMT group exhibited highly significant improvement on mean scores of FMA-WH (P < .001) and FMA-UE (P < .001) at postassessment in comparison to the control group. Furthermore, there was a 12% increase in the number of subjects at BRS stage 5 (out of synergy movement) in the experimental group as compared to a 0% rise at the same stage in the control group. This pilot trial confirmed the role of TBMT in improving the wrist-hand motor recovery in poststroke hemiparesis. MT using tasks may be used as an adjunct in stroke rehabilitation. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Inductive reasoning 2.0.

PubMed

Hayes, Brett K; Heit, Evan

2018-05-01

Inductive reasoning entails using existing knowledge to make predictions about novel cases. The first part of this review summarizes key inductive phenomena and critically evaluates theories of induction. We highlight recent theoretical advances, with a special emphasis on the structured statistical approach, the importance of sampling assumptions in Bayesian models, and connectionist modeling. A number of new research directions in this field are identified including comparisons of inductive and deductive reasoning, the identification of common core processes in induction and memory tasks and induction involving category uncertainty. The implications of induction research for areas as diverse as complex decision-making and fear generalization are discussed. This article is categorized under: Psychology > Reasoning and Decision Making Psychology > Learning. © 2017 Wiley Periodicals, Inc.

No-reference image quality assessment for horizontal-path imaging scenarios

NASA Astrophysics Data System (ADS)

Rios, Carlos; Gladysz, Szymon

2013-05-01

There exist several image-enhancement algorithms and tasks associated with imaging through turbulence that depend on defining the quality of an image. Examples include: "lucky imaging", choosing the width of the inverse filter for image reconstruction, or stopping iterative deconvolution. We collected a number of image quality metrics found in the literature. Particularly interesting are the blind, "no-reference" metrics. We discuss ways of evaluating the usefulness of these metrics, even when a fully objective comparison is impossible because of the lack of a reference image. Metrics are tested on simulated and real data. Field data comes from experiments performed by the NATO SET 165 research group over a 7 km distance in Dayton, Ohio.

Standardizing adult tracheostomy tube styles: what is the clinical and cost-effective impact?

PubMed

Crimlisk, Janet T; O'Donnell, Charles; Grillone, Gregory A

2006-01-01

Tracheostomy tubes are made of a variety of materials, components, and styles. In a recent merger of our hospitals, we noted a large assortment of tubes available for clinicians. The different tubes resulted in complaints from staff, which included confusion, delays in obtaining preferred tubes, and inconsistent shelf stock. A multidisciplinary task force was formed to recommend standardizing the styles of tracheostomy tubes. A comparison of tracheotomy procedures, tracheostomy tube usage, and tube costs were done 6 months before and 6 months after the standardization. The number of tube styles decreased from 9 to 4; specialty extra-long tubes decreased from 3 to 2. There were no cost savings in standardizing the tracheostomy tubes.

Cross-view gait recognition using joint Bayesian

NASA Astrophysics Data System (ADS)

Li, Chao; Sun, Shouqian; Chen, Xiaoyu; Min, Xin

2017-07-01

Human gait, as a soft biometric, helps to recognize people by walking. To further improve the recognition performance under cross-view condition, we propose Joint Bayesian to model the view variance. We evaluated our prosed method with the largest population (OULP) dataset which makes our result reliable in a statically way. As a result, we confirmed our proposed method significantly outperformed state-of-the-art approaches for both identification and verification tasks. Finally, sensitivity analysis on the number of training subjects was conducted, we find Joint Bayesian could achieve competitive results even with a small subset of training subjects (100 subjects). For further comparison, experimental results, learning models, and test codes are available.

Age-Related Differences in Transfer Costs: Evidence From Go/Nogo Tasks

PubMed Central

Vallesi, Antonino; Hasher, Lynn; Stuss, Donald T.

2012-01-01

To assess whether age-related differences in suppressing nontarget material impact subsequent performance, the authors initially asked younger and older adults to perform a go/nogo task with colored letters used as conflicting go/nogo stimuli and 2 colored numbers as low-conflict nogo stimuli. Next, participants performed another go/nogo task. A previous number was reused as a nogo stimulus and the other as a go stimulus, with new numbers serving as a baseline. In a 1st block of trials, younger adults showed slower responses to previous nogo/now-go numbers than to new go numbers, an effect not shown by older adults. Alternative accounts of these differential transfer costs are discussed. PMID:20718536

Blazing Signature Filter: a library for fast pairwise similarity comparisons

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

Lee, Joon-Yong; Fujimoto, Grant M.; Wilson, Ryan

Identifying similarities between datasets is a fundamental task in data mining and has become an integral part of modern scientific investigation. Whether the task is to identify co-expressed genes in large-scale expression surveys or to predict combinations of gene knockouts which would elicit a similar phenotype, the underlying computational task is often a multi-dimensional similarity test. As datasets continue to grow, improvements to the efficiency, sensitivity or specificity of such computation will have broad impacts as it allows scientists to more completely explore the wealth of scientific data. A significant practical drawback of large-scale data mining is the vast majoritymore » of pairwise comparisons are unlikely to be relevant, meaning that they do not share a signature of interest. It is therefore essential to efficiently identify these unproductive comparisons as rapidly as possible and exclude them from more time-intensive similarity calculations. The Blazing Signature Filter (BSF) is a highly efficient pairwise similarity algorithm which enables extensive data mining within a reasonable amount of time. The algorithm transforms datasets into binary metrics, allowing it to utilize the computationally efficient bit operators and provide a coarse measure of similarity. As a result, the BSF can scale to high dimensionality and rapidly filter unproductive pairwise comparison. Two bioinformatics applications of the tool are presented to demonstrate the ability to scale to billions of pairwise comparisons and the usefulness of this approach.« less

Operating Reserves and Wind Power Integration: An International Comparison; Preprint

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

Milligan, M.; Donohoo, P.; Lew, D.

2010-10-01

This paper provides a high-level international comparison of methods and key results from both operating practice and integration analysis, based on an informal International Energy Agency Task 25: Large-scale Wind Integration.

Mission analysis of photovoltaic solar energy systems. Quarterly progress report, 1 March 1976-31 May 1976

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

Leonard, S.L.; Munjal, P.K.; Rattin, E.J.

1976-06-01

The main emphasis of the activity during the second quarter of this project continued to be on Task 1, Analysis of Near-Term Missions, and on Task 2, Analysis of Major Mid-Term Missions. In addition, considerable progress was also made on Task 6, Comparison of the True Societal Costs of Conventional and Photovoltaic Power Production, and starts were made on Task 3, Review and Updating of the ERDA Technology Implementation Plan, and Task 4, Critical External Issues. As was planned, work on Task 5, Impact of Incentives, was deferred to the second half of the program. Progress is reported. (WHK)

Development of Physical Employment Standards for the Royal Australian Navy: Validation of Identified Whole-of-ship Tasks

DTIC Science & Technology

2014-11-01

to determining individual CS tasks, this partially satisfied Navy’s request to quantify the physical demands of the course in order to draw parity ...will enable comparison between task demands on the course and during on-board duties. These data will be used to determine whether there is parity ...between the physical and physiological demands of the ACSC (or components of it) and CS tasks performed on-board each platform. If parity is drawn

Uniform task level definitions for robotic system performance comparisons

NASA Technical Reports Server (NTRS)

Price, Charles; Tesar, Delbert

1989-01-01

A series of ten task levels of increasing difficulty was compiled for use in comparative performance evaluations of available and future robotics technology. Each level has a breakdown of ten additional levels of difficulty to provide a layering of 100 levels. It is assumed that each level of task performance must be achieved by the system before it can be appropriately considered for the next level.

Reflective Analysis as a Tool for Task Redesign: The Case of Prospective Elementary Teachers Solving and Posing Fraction Comparison Problems

ERIC Educational Resources Information Center

Thanheiser, Eva; Olanoff, Dana; Hillen, Amy; Feldman, Ziv; Tobias, Jennifer M.; Welder, Rachael M.

2016-01-01

Mathematical task design has been a central focus of the mathematics education research community over the last few years. In this study, six university teacher educators from six different US institutions formed a community of practice to explore key aspects of task design (planning, implementing, reflecting, and modifying) in the context of…

Escher in color space: individual-differences multidimensional scaling of color dissimilarities collected with a gestalt formation task.

PubMed

Bimler, David; Kirkland, John; Pichler, Shaun

2004-02-01

The structure of color perception can be examined by collecting judgments about color dissimilarities. In the procedure used here, stimuli are presented three at a time on a computer monitor and the spontaneous grouping of most-similar stimuli into gestalts provides the dissimilarity comparisons. Analysis with multidimensional scaling allows such judgments to be pooled from a number of observers without obscuring the variations among them. The anomalous perceptions of color-deficient observers produce comparisons that are represented well by a geometric model of compressed individual color spaces, with different forms of deficiency distinguished by different directions of compression. The geometrical model is also capable of accommodating the normal spectrum of variation, so that there is greater variation in compression parameters between tests on normal subjects than in those between repeated tests on individual subjects. The method is sufficiently sensitive and the variations sufficiently large that they are not obscured by the use of a range of monitors, even under somewhat loosely controlled conditions.

Combining evidence using likelihood ratios in writer verification

NASA Astrophysics Data System (ADS)

Srihari, Sargur; Kovalenko, Dimitry; Tang, Yi; Ball, Gregory

2013-01-01

Forensic identification is the task of determining whether or not observed evidence arose from a known source. It involves determining a likelihood ratio (LR) - the ratio of the joint probability of the evidence and source under the identification hypothesis (that the evidence came from the source) and under the exclusion hypothesis (that the evidence did not arise from the source). In LR- based decision methods, particularly handwriting comparison, a variable number of input evidences is used. A decision based on many pieces of evidence can result in nearly the same LR as one based on few pieces of evidence. We consider methods for distinguishing between such situations. One of these is to provide confidence intervals together with the decisions and another is to combine the inputs using weights. We propose a new method that generalizes the Bayesian approach and uses an explicitly defined discount function. Empirical evaluation with several data sets including synthetically generated ones and handwriting comparison shows greater flexibility of the proposed method.

Children’s Mapping between Non-Symbolic and Symbolic Numerical Magnitudes and Its Association with Timed and Untimed Tests of Mathematics Achievement

PubMed Central

Brankaer, Carmen; Ghesquière, Pol; De Smedt, Bert

2014-01-01

The ability to map between non-symbolic numerical magnitudes and Arabic numerals has been put forward as a key factor in children’s mathematical development. This mapping ability has been mainly examined indirectly by looking at children’s performance on a symbolic magnitude comparison task. The present study investigated mapping in a more direct way by using a task in which children had to choose which of two choice quantities (Arabic digits or dot arrays) matched the target quantity (dot array or Arabic digit), thereby focusing on small quantities ranging from 1 to 9. We aimed to determine the development of mapping over time and its relation to mathematics achievement. Participants were 36 first graders (M = 6 years 8 months) and 46 third graders (M = 8 years 8 months) who all completed mapping tasks, symbolic and non-symbolic magnitude comparison tasks and standardized timed and untimed tests of mathematics achievement. Findings revealed that children are able to map between non-symbolic and symbolic representations and that this mapping ability develops over time. Moreover, we found that children’s mapping ability is related to timed and untimed measures of mathematics achievement, over and above the variance accounted for by their numerical magnitude comparison skills. PMID:24699664

The K-8 Aeronautics Internet Testbook: Project Plan-Year 3

NASA Technical Reports Server (NTRS)

Pallis, Jani Macari

1997-01-01

The Project Plan - Year 3 includes: the major tasks and milestones, the assignment of tasks, and the key personnel assigned to each task, a description of the milestone and major task, and the deliverables for the project. Milestones have project numbers ending in "0.0", such as "25.0.0 Phase III Development". Major tasks under that milestone begin with the same first number such as, "25.0.1 Develop Future Of Aeronautics". The assignment of tasks included in the Year 3 project plan contains the names of the key personnel responsible for the task and others participating on the task. Although the PI has the overall and ultimately responsible for all the tasks and milestones, the name of the first individual on a task or milestone is the person responsible for that task. Other names listed under that task will be participating on the task. Since there are two individuals at Cislunar Aerospace, Inc. with the name "J. Pallis", the principal investigator, Jani Macari Pallis is designated as PI in the Project Plan and James Pallis is designated as J. Pallis.

An investigation of the 'von Restorff' phenomenon in post-test workload ratings

NASA Technical Reports Server (NTRS)

Thornton, D. C.

1985-01-01

The von Restorff effect in post-task ratings of task difficulty is examined. Nine subjects performed a hovercraft simulation task which combined elements of skill-based tracking and rule- and knowledge-based process control for five days of one hour sessions. The effects of isolated increases in workload on rating of task performance, and on the number of command errors and river band hits are analyzed. It is observed that the position of the workload increase affects the number of bank hits and command errors. The data reveal that factors not directly related to the task performance influence subjective rating, and post-task ratings of workload are biased.

Flight Tasks and Metrics to Evaluate Laser Eye Protection in Flight Simulators

DTIC Science & Technology

2017-07-07

AFRL-RH-FS-TR-2017-0026 Flight Tasks and Metrics to Evaluate Laser Eye Protection in Flight Simulators Thomas K. Kuyk Peter A. Smith Solangia...34Flight Tasks and Metrics to Evaluate Laser Eye Protection in Flight Simulators" (AFRL-RH-FS-TR- 2017 - 0026 SHORTER.PATRI CK.D.1023156390 Digitally...SUBTITLE Flight Tasks and Metrics to Evaluate Laser Eye Protection in Flight Simulators 5a. CONTRACT NUMBER FA8650-14-D-6519 5b. GRANT NUMBER 5c

Identify Fractions and Decimals on a Number Line

ERIC Educational Resources Information Center

Shaughnessy, Meghan M.

2011-01-01

Tasks that ask students to label rational number points on a number line are common not only in curricula in the upper elementary school grades but also on state assessments. Such tasks target foundational rational number concepts: A fraction (or a decimal) is more than a shaded part of an area, a part of a pizza, or a representation using…

No one way ticket from orthography to semantics in recognition memory: N400 and P200 effects of associations.

PubMed

Stuellein, Nicole; Radach, Ralph R; Jacobs, Arthur M; Hofmann, Markus J

2016-05-15

Computational models of word recognition already successfully used associative spreading from orthographic to semantic levels to account for false memories. But can they also account for semantic effects on event-related potentials in a recognition memory task? To address this question, target words in the present study had either many or few semantic associates in the stimulus set. We found larger P200 amplitudes and smaller N400 amplitudes for old words in comparison to new words. Words with many semantic associates led to larger P200 amplitudes and a smaller N400 in comparison to words with a smaller number of semantic associations. We also obtained inverted response time and accuracy effects for old and new words: faster response times and fewer errors were found for old words that had many semantic associates, whereas new words with a large number of semantic associates produced slower response times and more errors. Both behavioral and electrophysiological results indicate that semantic associations between words can facilitate top-down driven lexical access and semantic integration in recognition memory. Our results support neurophysiologically plausible predictions of the Associative Read-Out Model, which suggests top-down connections from semantic to orthographic layers. Copyright © 2016 Elsevier B.V. All rights reserved.

Pairwise-Comparison Software

NASA Technical Reports Server (NTRS)

Ricks, Wendell R.

1995-01-01

Pairwise comparison (PWC) is computer program that collects data for psychometric scaling techniques now used in cognitive research. It applies technique of pairwise comparisons, which is one of many techniques commonly used to acquire the data necessary for analyses. PWC administers task, collects data from test subject, and formats data for analysis. Written in Turbo Pascal v6.0.

Development of Fraction Comparison Strategies: A Latent Transition Analysis

ERIC Educational Resources Information Center

Rinne, Luke F.; Ye, Ai; Jordan, Nancy C.

2017-01-01

The present study investigated the development of fraction comparison strategies through a longitudinal analysis of children's responses to a fraction comparison task in 4th through 6th grades (N = 394). Participants were asked to choose the larger value for 24 fraction pairs blocked by fraction type. Latent class analysis of performance over item…

Comparison of precision and speed in laparoscopic and robot-assisted surgical task performance.

PubMed

Zihni, Ahmed; Gerull, William D; Cavallo, Jaime A; Ge, Tianjia; Ray, Shuddhadeb; Chiu, Jason; Brunt, L Michael; Awad, Michael M

2018-03-01

Robotic platforms have the potential advantage of providing additional dexterity and precision to surgeons while performing complex laparoscopic tasks, especially for those in training. Few quantitative evaluations of surgical task performance comparing laparoscopic and robotic platforms among surgeons of varying experience levels have been done. We compared measures of quality and efficiency of Fundamentals of Laparoscopic Surgery task performance on these platforms in novices and experienced laparoscopic and robotic surgeons. Fourteen novices, 12 expert laparoscopic surgeons (>100 laparoscopic procedures performed, no robotics experience), and five expert robotic surgeons (>25 robotic procedures performed) performed three Fundamentals of Laparoscopic Surgery tasks on both laparoscopic and robotic platforms: peg transfer (PT), pattern cutting (PC), and intracorporeal suturing. All tasks were repeated three times by each subject on each platform in a randomized order. Mean completion times and mean errors per trial (EPT) were calculated for each task on both platforms. Results were compared using Student's t-test (P < 0.05 considered statistically significant). Among novices, greater errors were noted during laparoscopic PC (Lap 2.21 versus Robot 0.88 EPT, P < 0.001). Among expert laparoscopists, greater errors were noted during laparoscopic PT compared with robotic (PT: Lap 0.14 versus Robot 0.00 EPT, P = 0.04). Among expert robotic surgeons, greater errors were noted during laparoscopic PC compared with robotic (Lap 0.80 versus Robot 0.13 EPT, P = 0.02). Among expert laparoscopists, task performance was slower on the robotic platform compared with laparoscopy. In comparisons of expert laparoscopists performing tasks on the laparoscopic platform and expert robotic surgeons performing tasks on the robotic platform, expert robotic surgeons demonstrated fewer errors during the PC task (P = 0.009). Robotic assistance provided a reduction in errors at all experience levels for some laparoscopic tasks, but no benefit in the speed of task performance. Robotic assistance may provide some benefit in precision of surgical task performance. Copyright © 2017 Elsevier Inc. All rights reserved.

Sequence comparison alignment-free approach based on suffix tree and L-words frequency.

PubMed

Soares, Inês; Goios, Ana; Amorim, António

2012-01-01

The vast majority of methods available for sequence comparison rely on a first sequence alignment step, which requires a number of assumptions on evolutionary history and is sometimes very difficult or impossible to perform due to the abundance of gaps (insertions/deletions). In such cases, an alternative alignment-free method would prove valuable. Our method starts by a computation of a generalized suffix tree of all sequences, which is completed in linear time. Using this tree, the frequency of all possible words with a preset length L-L-words--in each sequence is rapidly calculated. Based on the L-words frequency profile of each sequence, a pairwise standard Euclidean distance is then computed producing a symmetric genetic distance matrix, which can be used to generate a neighbor joining dendrogram or a multidimensional scaling graph. We present an improvement to word counting alignment-free approaches for sequence comparison, by determining a single optimal word length and combining suffix tree structures to the word counting tasks. Our approach is, thus, a fast and simple application that proved to be efficient and powerful when applied to mitochondrial genomes. The algorithm was implemented in Python language and is freely available on the web.

An experimental comparison of fuzzy logic and analytic hierarchy process for medical decision support systems.

PubMed

Uzoka, Faith-Michael Emeka; Obot, Okure; Barker, Ken; Osuji, J

2011-07-01

The task of medical diagnosis is a complex one, considering the level vagueness and uncertainty management, especially when the disease has multiple symptoms. A number of researchers have utilized the fuzzy-analytic hierarchy process (fuzzy-AHP) methodology in handling imprecise data in medical diagnosis and therapy. The fuzzy logic is able to handle vagueness and unstructuredness in decision making, while the AHP has the ability to carry out pairwise comparison of decision elements in order to determine their importance in the decision process. This study attempts to do a case comparison of the fuzzy and AHP methods in the development of medical diagnosis system, which involves basic symptoms elicitation and analysis. The results of the study indicate a non-statistically significant relative superiority of the fuzzy technology over the AHP technology. Data collected from 30 malaria patients were used to diagnose using AHP and fuzzy logic independent of one another. The results were compared and found to covary strongly. It was also discovered from the results of fuzzy logic diagnosis covary a little bit more strongly to the conventional diagnosis results than that of AHP. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Updating and feature overwriting in short-term memory for timbre.

PubMed

Mercer, Tom; McKeown, Denis

2010-11-01

Previous research has demonstrated a potent, stimulus-specific form of interference in short-term auditory memory. This effect has been interpreted in terms of interitem confusion and grouping, but the present experiments suggested that interference might be a feature-specific phenomenon. Participants compared standard and comparison tones over a 10-sec interval and were required to determine whether they differed in timbre. A single interfering distractor tone was presented either 50 msec or 8 sec after the offset of the standard (Experiment 1) or 2 sec prior to its onset (Experiment 2). The distractor varied in the number of features it shared with the standard and comparison, and this proved critical, since performance on the task was greatly impaired when the distractor either consisted of novel, unshared features (Experiment 1) or contained the distinguishing feature of the comparison tone (Experiments 1 and 2). These findings were incompatible with earlier accounts of forgetting but were fully explicable by the recent timbre memory model, which associates interference in short-term auditory memory with an "updating" process and feature overwriting. These results suggest similarities with the mechanisms that underlie forgetting in verbal short-term memory.

Dual-task interference effects on cross-modal numerical order and sound intensity judgments: the more the louder?

PubMed

Alards-Tomalin, Doug; Walker, Alexander C; Nepon, Hillary; Leboe-McGowan, Launa C

2017-09-01

In the current study, cross-task interactions between number order and sound intensity judgments were assessed using a dual-task paradigm. Participants first categorized numerical sequences composed of Arabic digits as either ordered (ascending, descending) or non-ordered. Following each number sequence, participants then had to judge the intensity level of a target sound. Experiment 1 emphasized processing the two tasks independently (serial processing), while Experiments 2 and 3 emphasized processing the two tasks simultaneously (parallel processing). Cross-task interference occurred only when the task required parallel processing and was specific to ascending numerical sequences, which led to a higher proportion of louder sound intensity judgments. In Experiment 4 we examined whether this unidirectional interaction was the result of participants misattributing enhanced processing fluency experienced on ascending sequences as indicating a louder target sound. The unidirectional finding could not be entirely attributed to misattributed processing fluency, and may also be connected to experientially derived conceptual associations between ascending number sequences and greater magnitude, consistent with conceptual mapping theory.

What drives the 'August effect'? A observational study of the effect of junior doctor changeover on out of hours work.

PubMed

Blakey, John D; Fearn, Andrew; Shaw, Dominick E

2013-01-01

To investigate whether measurements of junior doctor on-call workload and performance can clarify the mechanisms underlying the increase in morbidity and mortality seen after junior doctor changeover: the 'August effect'. Quantitative retrospective observational study of routinely collected data on junior doctor workload. Two large teaching hospitals in England. Task level data from a wireless out of hours system (n = 29,885 requests) used by medical staff, nurses, and allied health professionals. Number and type of tasks requested by nurses, time to completion of tasks by junior doctors. There was no overall change in the number of tasks requested by nurses out of hours around the August changeover (median requests per hour 15 before and 14 after, p = 0.46). However, the number of tasks classified as urgent was greater (p = 0.016) equating to five more urgent tasks per day. After changeover, doctors took less time to complete tasks overall due to a reduction in time taken for routine tasks (median 74 vs. 66 min; p = 3.9 × 10(-9)). This study suggests that the 'August effect' is not due to new junior doctors completing tasks more slowly or having a greater workload. Further studies are required to investigate the causes of the increased number of urgent tasks seen, but likely factors are errors, omissions, and poor prioritization. Thus, improved training and quality control has the potential to address this increased duration of unresolved patient risk. The study also highlights the potential of newer technologies to facilitate quantitative study of clinical activity.

Prefrontal contributions to domain-general executive control processes during temporal context retrieval.

PubMed

Rajah, M Natasha; Ames, Blaine; D'Esposito, Mark

2008-03-07

Neuroimaging studies have reported increased prefrontal cortex (PFC) activity during temporal context retrieval versus recognition memory. However, it remains unclear if these activations reflect PFC contributions to domain-general executive control processes or domain-specific retrieval processes. To gain a better understanding of the functional roles of these various PFC regions during temporal context retrieval we propose it is necessary to examine PFC activity across tasks from different domains, in which parallel manipulations are included targeting specific cognitive processes. In the current fMRI study, we examined domain-general and domain-specific PFC contributions to temporal context retrieval by increasing stimulus (but maintaining response number) and increasing response number (but maintaining stimulus number) across temporal context memory and ordering control tasks, for faces. The control task required subjects to order faces from youngest to oldest. Our behavioral results indicate that the combination of increased stimulus and response numbers significantly increased task difficulty for temporal context retrieval and ordering tasks. Across domains, increasing stimulus number, while maintaining response numbers, caused greater right lateral premotor cortex (BA 6/8) activity; whereas increasing response number, while maintaining stimulus number, caused greater domain-general left DLPFC (BA 9) and VLPFC (BA 44/45) activity. In addition, we found domain-specific right DLPFC (BA 9) activity only during retrieval events. These results highlight the functional heterogeneity of frontal cortex, and suggest its involvement in temporal context retrieval is related to its role in various cognitive control processes.

Clinical Reasoning Tasks and Resident Physicians: What Do They Reason About?

PubMed

McBee, Elexis; Ratcliffe, Temple; Goldszmidt, Mark; Schuwirth, Lambert; Picho, Katherine; Artino, Anthony R; Masel, Jennifer; Durning, Steven J

2016-07-01

A framework of clinical reasoning tasks thought to occur in a clinical encounter was recently developed. It proposes that diagnostic and therapeutic reasoning comprise 24 tasks. The authors of this current study used this framework to investigate what internal medicine residents reason about when they approach straightforward clinical cases. Participants viewed three video-recorded clinical encounters portraying common diagnoses. After each video, participants completed a post encounter form and think-aloud protocol. Two authors analyzed transcripts from the think-aloud protocols using a constant comparative approach. They conducted iterative coding of the utterances, classifying each according to the framework of clinical reasoning tasks. They evaluated the type, number, and sequence of tasks the residents used. Ten residents participated in the study in 2013-2014. Across all three cases, the residents employed 14 clinical reasoning tasks. Nearly all coded tasks were associated with framing the encounter or diagnosis. The order in which residents used specific tasks varied. The average number of tasks used per case was as follows: Case 1, 4.4 (range 1-10); Case 2, 4.6 (range 1-6); and Case 3, 4.7 (range 1-7). The residents used some tasks repeatedly; the average number of task utterances was 11.6, 13.2, and 14.7 for, respectively, Case 1, 2, and 3. Results suggest that the use of clinical reasoning tasks occurs in a varied, not sequential, process. The authors provide suggestions for strengthening the framework to more fully encompass the spectrum of reasoning tasks that occur in residents' clinical encounters.

Nothing New Under the Sun: Benefiting from the Great Lessons of History to Develop a Coherent Cyberspace Deterrence Strategy

DTIC Science & Technology

2012-05-12

LESSONS OF HISTORY TO DEVELOP A COHERENT CYBERSPACE DETERRENCE STRATEGY 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHDR!SI 5d. PROJECT ...AFOSR-82-1234. 5c. PROGRAM ELEMENT NUMBER. Enter all program element numbers as they appear in the report, e.g. 61101 A. 5d. PROJECT NUMBER...Enter all project numbers as they appear in the report, e.g. 1F665702D1257; ILIR. 5e. TASK NUMBER. Enter all task numbers as they appear in the

SU-F-BRB-07: A Plan Comparison Tool to Ensure Robustness and Deliverability in Online-Adaptive Radiotherapy

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

Hill, P; Labby, Z; Bayliss, R A

Purpose: To develop a plan comparison tool that will ensure robustness and deliverability through analysis of baseline and online-adaptive radiotherapy plans using similarity metrics. Methods: The ViewRay MRIdian treatment planning system allows export of a plan file that contains plan and delivery information. A software tool was developed to read and compare two plans, providing information and metrics to assess their similarity. In addition to performing direct comparisons (e.g. demographics, ROI volumes, number of segments, total beam-on time), the tool computes and presents histograms of derived metrics (e.g. step-and-shoot segment field sizes, segment average leaf gaps). Such metrics were investigatedmore » for their ability to predict that an online-adapted plan reasonably similar to a baseline plan where deliverability has already been established. Results: In the realm of online-adaptive planning, comparing ROI volumes offers a sanity check to verify observations found during contouring. Beyond ROI analysis, it has been found that simply editing contours and re-optimizing to adapt treatment can produce a delivery that is substantially different than the baseline plan (e.g. number of segments increased by 31%), with no changes in optimization parameters and only minor changes in anatomy. Currently the tool can quickly identify large omissions or deviations from baseline expectations. As our online-adaptive patient population increases, we will continue to develop and refine quantitative acceptance criteria for adapted plans and relate them historical delivery QA measurements. Conclusion: The plan comparison tool is in clinical use and reports a wide range of comparison metrics, illustrating key differences between two plans. This independent check is accomplished in seconds and can be performed in parallel to other tasks in the online-adaptive workflow. Current use prevents large planning or delivery errors from occurring, and ongoing refinements will lead to increased assurance of plan quality.« less

Forensic Comparison and Matching of Fingerprints: Using Quantitative Image Measures for Estimating Error Rates through Understanding and Predicting Difficulty

PubMed Central

Kellman, Philip J.; Mnookin, Jennifer L.; Erlikhman, Gennady; Garrigan, Patrick; Ghose, Tandra; Mettler, Everett; Charlton, David; Dror, Itiel E.

2014-01-01

Latent fingerprint examination is a complex task that, despite advances in image processing, still fundamentally depends on the visual judgments of highly trained human examiners. Fingerprints collected from crime scenes typically contain less information than fingerprints collected under controlled conditions. Specifically, they are often noisy and distorted and may contain only a portion of the total fingerprint area. Expertise in fingerprint comparison, like other forms of perceptual expertise, such as face recognition or aircraft identification, depends on perceptual learning processes that lead to the discovery of features and relations that matter in comparing prints. Relatively little is known about the perceptual processes involved in making comparisons, and even less is known about what characteristics of fingerprint pairs make particular comparisons easy or difficult. We measured expert examiner performance and judgments of difficulty and confidence on a new fingerprint database. We developed a number of quantitative measures of image characteristics and used multiple regression techniques to discover objective predictors of error as well as perceived difficulty and confidence. A number of useful predictors emerged, and these included variables related to image quality metrics, such as intensity and contrast information, as well as measures of information quantity, such as the total fingerprint area. Also included were configural features that fingerprint experts have noted, such as the presence and clarity of global features and fingerprint ridges. Within the constraints of the overall low error rates of experts, a regression model incorporating the derived predictors demonstrated reasonable success in predicting objective difficulty for print pairs, as shown both in goodness of fit measures to the original data set and in a cross validation test. The results indicate the plausibility of using objective image metrics to predict expert performance and subjective assessment of difficulty in fingerprint comparisons. PMID:24788812

Set size, individuation, and attention to shape

PubMed Central

Cantrell, Lisa; Smith, Linda B.

2013-01-01

Much research has demonstrated a shape bias in categorizing and naming solid objects. This research has shown that when an entity is conceptualized as an individual object, adults and children attend to the object’s shape. Separate research in the domain of numerical cognition suggest that there are distinct processes for quantifying small and large sets of discrete items. This research shows that small set discrimination, comparison, and apprehension is often precise for 1–3 and sometimes 4 items; however, large numerosity representation is imprecise. Results from three experiments suggest a link between the processes for small and large number representation and the shape bias in a forced choice categorization task using naming and non-naming procedures. Experiment 1 showed that adults generalized a newly learned name for an object to new instances of the same shape only when those instances were presented in sets of less than 3 or 4. Experiment 2 showed that preschool children who were monolingual speakers of three different languages were also influenced by set size when categorizing objects in sets. Experiment 3 extended these results and showed the same effect in a non-naming task and when the novel noun was presented in a count-noun syntax frame. The results are discussed in terms of a relation between the precision of object representation and the precision of small and large number representation. PMID:23167969

Set size, individuation, and attention to shape.

PubMed

Cantrell, Lisa; Smith, Linda B

2013-02-01

Much research has demonstrated a shape bias in categorizing and naming solid objects. This research has shown that when an entity is conceptualized as an individual object, adults and children attend to the object's shape. Separate research in the domain of numerical cognition suggest that there are distinct processes for quantifying small and large sets of discrete items. This research shows that small set discrimination, comparison, and apprehension is often precise for 1-3 and sometimes 4 items; however, large numerosity representation is imprecise. Results from three experiments suggest a link between the processes for small and large number representation and the shape bias in a forced choice categorization task using naming and non-naming procedures. Experiment 1 showed that adults generalized a newly learned name for an object to new instances of the same shape only when those instances were presented in sets of less than 3 or 4. Experiment 2 showed that preschool children who were monolingual speakers of three different languages were also influenced by set size when categorizing objects in sets. Experiment 3 extended these results and showed the same effect in a non-naming task and when the novel noun was presented in a count-noun syntax frame. The results are discussed in terms of a relation between the precision of object representation and the precision of small and large number representation. Copyright © 2012 Elsevier B.V. All rights reserved.

[Developmental changes of rapid automatized naming and Hiragana reading of Japanese in elementary-school children].

PubMed

Kobayashi, Tomoka; Inagaki, Masumi; Gunji, Atsuko; Yatabe, Kiyomi; Kita, Yosuke; Kaga, Makiko; Gotoh, Takaaki; Koike, Toshihide

2011-11-01

Two hundred and seven Japanese elementary school children aged from 6 (Grade 1) to 12 (Grade 6) years old were tested for their abilities to name numbers and pictured objects along with reading Hiragana characters and words. These children all showed typical development and their classroom teachers judged that they were not having any problems with reading or writing. The children were randomly divided into two groups, the first group was assigned to two naming tasks;the rapid automatized naming (RAN) of "numbers" and "pictured objects," the second group was assigned to two rapid alternative stimulus (RAS) naming tasks using numbers and pictured objects. All children were asked to perform two reading tasks that were written in Hiragana script: single mora reading task and four syllable word reading task. The total articulation time for naming and reading and performance in terms of accuracy were measured for each task. Developmental changes in these variables were evaluated. The articulation time was significantly longer for the first graders, and it gradually shortened as they moved through to the upper grades in all tasks. The articulation time reached a plateau in the 5th grade for the number naming, while gradual change continued after drastic change in the lower grades for the pictured object naming. The articulation times for the single mora reading and RAN of numbers correlated strongly. The articulation time for the RAS naming was significantly longer compared to that for the RAN, though there were very few errors. The RAS naming showed the highest correlation with the four syllable word reading. This study demonstrated that the performance in rapid automatized naming of numbers and pictures were closely related with performance on reading tasks. Thus Japanese children with reading disorders such as developmental dyslexia should also be evaluated for rapid automatized naming.

Is anorexia nervosa a version of autism spectrum disorders?

PubMed

Oldershaw, Anna; Treasure, Janet; Hambrook, David; Tchanturia, Kate; Schmidt, Ulrike

2011-01-01

Similarities have been noted between cognitive profiles of anorexia nervosa (AN) and autism spectrum disorders (ASD). However, there are no direct comparison studies. This study aimed to compare the cognitive profile of AN against published ASD data on tasks measuring empathy, executive function and central coherence. Currently ill AN outpatients (n = 40) were statistically compared against published ASD scores on Reading the Mind in the Eyes, Voice and Films tasks (assessing empathy), Wisconsin Card Sorting Task (WCST) (assessing executive function) and Embedded Figures Task (EFT) (assessing detail focus aspect of central coherence). Cognitive profiles of the groups were statistically similar, except for differences in the relative patterns of empathy scores. The cognitive profile in current AN resembles that of ASD with important clinical implications. Replication studies with planned comparisons, examination of the state-or trait-nature of AN profile and clarification of factors underpinning similarities are required in order to broaden understanding of both disorders. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.

Effect of aquatic dual-task training on balance and gait in stroke patients

PubMed Central

Kim, Kyoung; Lee, Dong-Kyu; Kim, Eun-Kyung

2016-01-01

[Purpose] The purpose of this study was to determine the effect of aquatic dual-task training on balance and gait in stroke patients. [Subjects and Methods] Twenty stroke patients were divided into the experimental (n=10) and control (n=10) groups. Both groups underwent neurodevelopmental treatment. The experimental group additionally underwent aquatic dual-task training for 30 minutes a day, 5 days a week, for 6 weeks. Balance was measured using the Berg balance scale, Five Times Sit-to Stand Test, and Functional Reach Test. Gait was measured using the 10-Meter Walk Test, Timed Up and Go Test, and Functional Gait Assessment. [Results] For intragroup comparison, the experimental group showed a significant change after the experiment in all balance and gait assessment tests. For intergroup comparison, the experimental group showed relatively more significant change after the experiment in all balance and gait assessment tests. [Conclusion] Our results showed that aquatic dual-task training has a positive effect on balance and gait in stroke patients. PMID:27512261

Effect of aquatic dual-task training on balance and gait in stroke patients.

PubMed

Kim, Kyoung; Lee, Dong-Kyu; Kim, Eun-Kyung

2016-07-01

[Purpose] The purpose of this study was to determine the effect of aquatic dual-task training on balance and gait in stroke patients. [Subjects and Methods] Twenty stroke patients were divided into the experimental (n=10) and control (n=10) groups. Both groups underwent neurodevelopmental treatment. The experimental group additionally underwent aquatic dual-task training for 30 minutes a day, 5 days a week, for 6 weeks. Balance was measured using the Berg balance scale, Five Times Sit-to Stand Test, and Functional Reach Test. Gait was measured using the 10-Meter Walk Test, Timed Up and Go Test, and Functional Gait Assessment. [Results] For intragroup comparison, the experimental group showed a significant change after the experiment in all balance and gait assessment tests. For intergroup comparison, the experimental group showed relatively more significant change after the experiment in all balance and gait assessment tests. [Conclusion] Our results showed that aquatic dual-task training has a positive effect on balance and gait in stroke patients.

Don’t Ask, Don’t Tell: Time for Change

DTIC Science & Technology

2009-02-02

5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army War College ,122 Forbes Ave.,Carlisle,PA,17013...5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Stephen Gerras Department of Command...separated using laws targeting unacceptable or antisocial conduct. During World War II military regulations decriminalized homosexuality, determining