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Sunday, February 17, 2013

Ahead of the curve

 

How to Make a Young Child Smarter: Evidence From the Database of Raising Intelligence

John Protzko, Joshua Aronson & Clancy Blair
Perspectives on Psychological Science, January 2013, Pages 25-40

Abstract:
Can interventions meaningfully increase intelligence? If so, how? The Database of Raising Intelligence is a continuously updated compendium of randomized controlled trials that were designed to increase intelligence. In this article, the authors examine nearly every available intervention involving children from birth to kindergarten, using meta-analytic procedures when more than 3 studies tested similar methods and reviewing interventions when too few were available for meta-analysis. This yielded 4 meta-analyses on the effects of dietary supplementation to pregnant mothers and neonates, early educational interventions, interactive reading, and sending a child to preschool. All 4 meta-analyses yielded significant results: Supplementing infants with long-chain polyunsaturated fatty acids, enrolling children in early educational interventions, reading to children in an interactive manner, and sending children to preschool all raise the intelligence of young children.

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Is cognitive ability a liability? A critique and future research agenda on skilled performance

Margaret Beier & Frederick Oswald
Journal of Experimental Psychology: Applied, December 2012, Pages 331-345

Abstract:
Over a century of psychological research provides strong and consistent support for the idea that cognitive ability correlates positively with success in tasks that people face in employment, education, and everyday life. Recent experimental research, however, has converged on a different and provocative conclusion, namely that lower-ability people can actually be more effective performers within special environments characterized by features such as time pressure, social evaluation, and unpredictable task change. If this conclusion is true, it has extensive implications for practices such as personnel selection, training design, and teaching methods. The current article reexamines and reinterprets this research within the context of well-established resource theories of cognitive processing and skill acquisition leading to a less provocative conclusion that serves to reiterate the benefits of cognitive ability for task performance. Following this reexamination, we conclude by providing a research agenda for examining the determinants of skilled performance in dynamic task environments, including the following: (a) broadening the range of abilities and task difficulties examined, (b) considering the role of nonability traits and goals in skilled performance (e.g., personality, learning, and performance goals), (c) investigating the processes (e.g., problem solving strategies) that people use in complex environments, (d) developing research designs and analytic strategies for examining adaptive performance, and (e) investigating how best to train for adaptive performance.

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Who Multi-Tasks and Why? Multi-Tasking Ability, Perceived Multi-Tasking Ability, Impulsivity, and Sensation Seeking

David Sanbonmatsu et al.
PLoS ONE, January 2013

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

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Poverty as a predictor of 4-year-olds' executive function: New perspectives on models of differential susceptibility

Cybele Raver et al.
Developmental Psychology, February 2013, Pages 292-304

Abstract:
In a predominantly low-income, population-based longitudinal sample of 1,259 children followed from birth, results suggest that chronic exposure to poverty and the strains of financial hardship were each uniquely predictive of young children's performance on measures of executive functioning. Results suggest that temperament-based vulnerability serves as a statistical moderator of the link between poverty-related risk and children's executive functioning. Implications for models of ecology and biology in shaping the development of children's self-regulation are discussed.

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How leader displays of happiness and sadness influence follower performance: Emotional contagion and creative versus analytical performance

Victoria Visser et al.
Leadership Quarterly, February 2013, Pages 172-188

Abstract:
Previous studies have found mixed results regarding the influence of positive and negative leader affect on follower performance. We propose that both leader happiness and leader sadness can be beneficial for follower performance contingent on whether the task concerns creative or analytical performance. This proposition was put to the test in two experiments in which leader affective display was manipulated and the performance of (student) participants was assessed. The results supported our hypothesis that a leader's displays of happiness enhance follower creative performance, whereas a leader's displays of sadness enhance follower analytical performance. Contrasting these findings with evidence for a subjective rating of leadership effectiveness, in line with an implicit leadership theory interpretation, leaders were perceived as more effective when displaying happiness rather than sadness irrespective of task type. The second study showed that the effects of leader affective displays on followers' creative performance and perceived leadership effectiveness are mediated by follower positive affect, indicating that emotional contagion partly underlies these effects.

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Priming divergent thinking promotes logical reasoning in 6- to 8-year olds: But more for high than low SES students

Henry Markovits & Marie-Laurence Brunet
Journal of Cognitive Psychology, Fall 2012, Pages 991-1001

Abstract:
Divergent thinking is a component of creativity. In the following study, we argue that this form of thinking also underlies logical reasoning. A total of 205 early elementary school children in Grades 1 and 2, from high and moderately low SES environments, were given a short-term prime for divergent thinking and simple reasoning problems. Overall, receiving this prime significantly improved logical reasoning at both grade levels. High and low SES students had similar levels of working memory, inhibitory control, performance on the divergent thinking task, and levels of logical reasoning without the prime. However, also consistent with our predictions, only high SES students showed overall improved logical reasoning following the divergent thinking prime, with the SES difference concentrated in the younger students. These results suggest that environmental differences in openness to alternatives and divergent thinking might underlie developing SES differences in levels of logical thinking.

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The role of general cognitive ability in moderating the relation of adverse life events to emotional and behavioural problems

Eirini Flouri, Stella Mavroveli & Constantina Panourgia
British Journal of Psychology, February 2013, Pages 130-139

Abstract:
Previous studies have established the role of various measures of cognitive functioning in dampening the association between adverse life events (‘life stress') and adolescents' emotional and behavioural problems. However, it is not yet clear if general cognitive ability (‘intelligence') is a protective factor. In this study of 1,175 10- to 19-year-olds in five secondary schools in England, we explored this issue. We found that even after controlling for sex, age, family poverty, and special educational needs, the association of life stress with emotional, hyperactivity, and conduct problems was significant. General cognitive ability moderated the association between life stress and conduct problems; among adolescents with higher than average general cognitive ability, the association between life stress and conduct problems was non-significant.

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Height and Cognitive Function at Older Ages: Is Height a Useful Summary Measure of Early Childhood Experiences?

Cahit Guven & Wang Sheng Lee
Health Economics, February 2013, Pages 224-233

Abstract:
Previous research using US data suggests that height, as a marker for early investments in health, is associated with better cognitive functioning in later life, but this association disappears once education is controlled for. Using an English cohort of men and women older than 50 years, we find that the association between height and cognitive outcomes remains significant after controlling for education suggesting that height affects cognitive functioning not simply via higher educational attainment. Furthermore, the significant association between height and cognitive function remains even after controls for early life indicators have been included.

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Neural Activity during Natural Viewing of Sesame Street Statistically Predicts Test Scores in Early Childhood

Jessica Cantlon & Rosa Li
PLoS ONE, January 2013

Abstract:
It is not currently possible to measure the real-world thought process that a child has while observing an actual school lesson. However, if it could be done, children's neural processes would presumably be predictive of what they know. Such neural measures would shed new light on children's real-world thought. Toward that goal, this study examines neural processes that are evoked naturalistically, during educational television viewing. Children and adults all watched the same Sesame Street video during functional magnetic resonance imaging (fMRI). Whole-brain intersubject correlations between the neural timeseries from each child and a group of adults were used to derive maps of "neural maturity" for children. Neural maturity in the intraparietal sulcus (IPS), a region with a known role in basic numerical cognition, predicted children's formal mathematics abilities. In contrast, neural maturity in Broca's area correlated with children's verbal abilities, consistent with prior language research. Our data show that children's neural responses while watching complex real-world stimuli predict their cognitive abilities in a content-specific manner. This more ecologically natural paradigm, combined with the novel measure of "neural maturity," provides a new method for studying real-world mathematics development in the brain.

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Effects of chewing on cognitive processing speed

Yoshiyuki Hirano et al.
Brain and Cognition, forthcoming

Abstract:
In recent years, chewing has been discussed as producing effects of maintaining and sustaining cognitive performance. We have reported that chewing may improve or recover the process of working memory; however, the mechanisms underlying these phenomena are still to be elucidated. We investigated the effect of chewing on aspects of attention and cognitive processing speed, testing the hypothesis that this effect induces higher cognitive performance. Seventeen healthy adults (20-34 years old) were studied during attention task with blood oxygenation level-dependent functional (fMRI) at 3.0 T MRI. The attentional network test (ANT) within a single task fMRI containing two cue conditions (no cue and center cue) and two target conditions (congruent and incongruent) was conducted to examine the efficiency of alerting and executive control. Participants were instructed to press a button with the right or left thumb according to the direction of a centrally presented arrow. Each participant underwent two back-to-back ANT sessions with or without chewing gum, odorless and tasteless to remove any effect other than chewing. Behavioral results showed that mean reaction time was significantly decreased during chewing condition, regardless of speed-accuracy trade-off, although there were no significant changes in behavioral effects (both alerting and conflict effects). On the other hand, fMRI analysis revealed higher activations in the anterior cingulate cortex and left frontal gyrus for the executive network and motor-related regions for both attentional networks during chewing condition. These results suggested that chewing induced an increase in the arousal level and alertness in addition to an effect on motor control and, as a consequence, these effects could lead to improvements in cognitive performance.

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There is no coherent evidence for a bilingual advantage in executive processing

Kenneth Paap & Zachary Greenberg
Cognitive Psychology, March 2013, Pages 232-258

Abstract:
Three studies compared bilinguals to monolinguals on 15 indicators of executive processing (EP). Most of the indicators compare a neutral or congruent baseline to a condition that should require EP. For each of the measures there was no main effect of group and a highly significant main effect of condition. The critical marker for a bilingual advantage, the Group × Condition interaction, was significant for only one indicator, but in a pattern indicative of a bilingual disadvantage. Tasks include antisaccade (Study 1), Simon (Studies 1-3), flanker (Study 3), and color-shape switching (Studies 1-3). The two groups performed identically on the Raven's Advanced Matrices test (Study 3). Analyses on the combined data selecting subsets that are precisely matched on parent's educational level or that include only highly fluent bilinguals reveal exactly the same pattern of results. A problem reconfirmed by the present study is that effects assumed to be indicators of a specific executive process in one task (e.g., inhibitory control in the flanker task) frequently do not predict individual differences in that same indicator on a related task (e.g., inhibitory control in the Simon task). The absence of consistent cross-task correlations undermines the interpretation that these are valid indicators of domain-general abilities. In a final discussion the underlying rationale for hypothesizing bilingual advantages in executive processing based on the special linguistic demands placed on bilinguals is interrogated.

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ERP-pupil size correlations reveal how bilingualism enhances cognitive flexibility

Jan-Rouke Kuipers & Guillaume Thierry
Cortex, forthcoming

Abstract:
A Bilingual upbringing has been shown to enhance executive control, but the neural mechanisms underpinning such effect are essentially unknown. Here, we investigated whether monolingual and bilingual toddlers differ in semantic processing efficiency and their allocation of attention to expected and unexpected visual stimuli. We simultaneously recorded event-related brain potentials (ERPs) and pupil size in monolingual and bilingual toddlers presented with (spoken) word-picture pairs. Although ERP effects elicited by semantic relatedness were indistinguishable between the two children groups, pictures unrelated to the preceding word evoked greater pupil dilation than related pictures in bilinguals, but not in monolinguals. Furthermore, increasing pupil dilation to unrelated pictures was associated with decreasing N400 amplitude in bilinguals, whereas the monolingual toddlers showed the opposite association. Hence, attention to unexpected stimuli seems to hamper semantic integration in monolinguals, but to facilitate semantic integration in bilinguals, suggesting that bilingual toddlers are more tolerant to variation in word-referent mappings. Given the link between pupil dilation and norepinephrine-driven cognitive efficiency, correlations between ERP amplitude and concurrent pupil dilation provide new insights into the neural bases of the bilingual cognitive advantage.

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Developmental patterns of chimpanzee cerebral tissues provide important clues for understanding the remarkable enlargement of the human brain

Tomoko Sakai et al.
Proceedings of the Royal Society: Biological Sciences, 22 February 2013

Abstract:
Developmental prolongation is thought to contribute to the remarkable brain enlargement observed in modern humans (Homo sapiens). However, the developmental trajectories of cerebral tissues have not been explored in chimpanzees (Pan troglodytes), even though they are our closest living relatives. To address this lack of information, the development of cerebral tissues was tracked in growing chimpanzees during infancy and the juvenile stage, using three-dimensional magnetic resonance imaging and compared with that of humans and rhesus macaques (Macaca mulatta). Overall, cerebral development in chimpanzees demonstrated less maturity and a more protracted course during prepuberty, as observed in humans but not in macaques. However, the rapid increase in cerebral total volume and proportional dynamic change in the cerebral tissue in humans during early infancy, when white matter volume increases dramatically, did not occur in chimpanzees. A dynamic reorganization of cerebral tissues of the brain during early infancy, driven mainly by enhancement of neuronal connectivity, is likely to have emerged in the human lineage after the split between humans and chimpanzees and to have promoted the increase in brain volume in humans. Our findings may lead to powerful insights into the ontogenetic mechanism underlying human brain enlargement.

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Associations of Maternal Weight Gain in Pregnancy With Offspring Cognition in Childhood and Adolescence: Findings From the Avon Longitudinal Study of Parents and Children

Suzanne Gage et al.
American Journal of Epidemiology, forthcoming

Abstract:
An association of gestational weight gain (GWG) with offspring cognition has been postulated. We used data from the Avon Longitudinal Study of Parents and Children, a United Kingdom prospective cohort (1990 through the present) with a median of 10 maternal weight measurements in pregnancy. These were used to allocate participants to 2009 Institute of Medicine weight-gain categories and in random effect linear spline models. Outcomes were School Entry Assessment score (age, 4 years; n = 5,832), standardized intelligence quotient assessed by Wechsler Intelligence Scale for Children (age, 8 years; n = 5,191), and school final-examination results (age, 16 years; n = 7,339). Offspring of women who gained less weight than recommended had a 0.075 standard deviation lower mean School Entry Assessment score (95% confidence interval: -0.127, -0.023) and were less likely to achieve adequate final-examination results (odds ratio = 0.88, 95% confidence interval: 0.78, 0.99) compared with offspring of women who gained as recommended. GWG in early pregnancy (defined as 0-18 weeks on the basis of a knot point at 18 weeks) and midpregnancy (defined as 18-28 weeks on the basis of knot points at 18 and 28 weeks) was positively associated with School Entry Assessment score and intelligence quotient. GWG in late pregnancy (defined as 28 weeks onward on the basis of a knot point at 28 weeks) was positively associated with offspring intelligence quotient and with increased odds of offspring achieving adequate final-examination results in mothers who were overweight prepregnancy. Findings support small positive associations between GWG and offspring cognitive development, which may have lasting effects on educational attainment up to age 16 years.

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The longer-term impacts of Western diet on human cognition and the brain

Heather Francis & Richard Stevenson
Appetite, April 2013, Pages 119-128

Abstract:
Animal work over the last three decades has generated a convincing body of evidence that a Western diet - one high in saturated fat and refined carbohydrates (HFS diet) - can damage various brain systems. In this review we examine whether there is evidence for this in humans, using converging lines of evidence from neuropsychological, epidemiological and neuroimaging data. Using the animal research as the organizing principal, we examined evidence for dietary induced impairments in frontal, limbic and hippocampal systems, and with their associated functions in learning, memory, cognition and hedonics. Evidence for the role of HFS diet in attention deficit disorder and in neurodegenerative conditions was also examined. While human research data is still at an early stage, there is evidence of an association between HFS diet and impaired cognitive function. Based upon the animal data, and a growing understanding of how HFS diets can disrupt brain function, we further suggest that there is a causal link running from HFS diet to impaired brain function in humans, and that HFS diets also contribute to the development of neurodegenerative conditions.

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The importance of intrinsic and extrinsic motivation for measuring IQ

Lex Borghans, Huub Meijers & Bas ter Weel
Economics of Education Review, forthcoming

Abstract:
This research provides an economic model of the way people behave during an IQ test. We distinguish a technology that describes how time investment improves performance from preferences that determine how much time people invest in each question. We disentangle these two elements empirically using data from a laboratory experiment. The main findings is that both intrinsic (questions that people like to work on) and extrinsic motivation (incentive payments) increase time investments and as a result performance. The presence of incentive payments seems to be more important than the size of the reward. Intrinsic and extrinsic motivation turn out to be complements.

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Early Childhood Lead Exposure and Academic Achievement: Evidence From Detroit Public Schools, 2008-2010

Nanhua Zhang et al.
American Journal of Public Health, March 2013, Pages e72-e77

Objectives: We assessed the long-term effect of early childhood lead exposure on academic achievement in mathematics, science, and reading among elementary and junior high school children.

Methods: We linked early childhood blood lead testing surveillance data from the Detroit Department of Health and Wellness Promotion to educational testing data from the Detroit, Michigan, public schools. We used the linked data to investigate the effect of early childhood lead exposure on academic achievement among school-aged children, both marginally and adjusted for grade level, gender, race, language, maternal education, and socioeconomic status.

Results: High blood lead levels before age 6 years were strongly associated with poor academic achievement in grades 3, 5, and 8. The odds of scoring less than proficient for those whose blood lead levels were greater than 10 micrograms per deciliter were more than twice the odds for those whose blood lead levels were less than 1 micrograms per deciliter after adjustment for potential confounders.

Conclusions: Early childhood lead exposure was negatively associated with academic achievement in elementary and junior high school, after adjusting for key potential confounders. The control of lead poisoning should focus on primary prevention of lead exposure in children and development of special education programs for students with lead poisoning.

By KEVIN LEWIS | 09:00:00 AM