Sequence learning under uncertainty in children: self-reflection vs. self-assertion

We know that stochastic feedback impairs children's associative stimulus-response (S-R) learning (Crone et al., 2004a; Eppinger et al., 2009), but the impact of stochastic feedback on sequence learning that involves deductive reasoning has not been not tested so far. In the current study, 8- to 11-year-old children (N = 171) learned a sequence of four left and right button presses, LLRR, RRLL, LRLR, RLRL, LRRL, and RLLR, which needed to be deduced from feedback because no directional cues were given. One group of children experienced consistent feedback only (deterministic feedback, 100% correct). In this condition, green feedback on the screen indicated that the children had been right when they were right, and red feedback indicated that the children had been wrong when they were wrong. Another group of children experienced inconsistent feedback (stochastic feedback, 85% correct, 15% false), where in some trials, green feedback on the screen could signal that children were right when in fact they were wrong, and red feedback could indicate that they were wrong when in fact they had been right. Independently of age, children's sequence learning in the stochastic condition was initially much lower than in the deterministic condition, but increased gradually and improved with practice. Responses toward positive vs. negative feedback varied with age. Children were increasingly able to understand that they could have been wrong when feedback indicated they were right (self-reflection), but they remained unable to understand that they could have been right when feedback indicated they were wrong (self-assertion)

Sequence Learning Under Uncertainty in Children: Self-Reflection vs. Self-Assertion

We know that stochastic feedback impairs children’s associative stimulus–response (S–R) learning (Crone et al., 2004a; Eppinger et al., 2009), but the impact of stochastic feedback on sequence learning that involves deductive reasoning has not been not tested so far. In the current study, 8- to 11-year-old children (N = 171) learned a sequence of four left and right button presses, LLRR, RRLL, LRLR, RLRL, LRRL, and RLLR, which needed to be deduced from feedback because no directional cues were given. One group of children experienced consistent feedback only (deterministic feedback, 100% correct). In this condition, green feedback on the screen indicated that the children had been right when they were right, and red feedback indicated that the children had been wrong when they were wrong. Another group of children experienced inconsistent feedback (stochastic feedback, 85% correct, 15% false), where in some trials, green feedback on the screen could signal that children were right when in fact they were wrong, and red feedback could indicate that they were wrong when in fact they had been right. Independently of age, children’s sequence learning in the stochastic condition was initially much lower than in the deterministic condition, but increased gradually and improved with practice. Responses toward positive vs. negative feedback varied with age. Children were increasingly able to understand that they could have been wrong when feedback indicated they were right (self-reflection), but they remained unable to understand that they could have been right when feedback indicated they were wrong (self-assertion)

Fine Motor Control Underlies the Association Between Response Inhibition and Drawing Skill in Early Development

Previous research shows that the development of response inhibition and drawing skill are linked. The current research investigated whether this association reflects a more fundamental link between response inhibition and motor control. In Experiment 1, 3- and 4-year-olds (n = 100) were tested on measures of inhibition, fine motor control, and drawing skill. Data revealed an association between inhibition and fine motor control, which was responsible for most of the association observed with drawing skill. Experiment 2 (n = 100) provided evidence that, unlike fine motor control, gross motor control and inhibition were not associated (after controlling for IQ). Alternative explanations for the link between inhibition and fine motor control are outlined, including a consideration of how these cognitive processes may interact during development

The FERM protein EPB41L5 regulates actomyosin contractility and focal adhesion formation to maintain the kidney filtration barrier

Podocytes form the outer part of the glomerular filter, where they have to withstand enormous transcapillary filtration forces driving glomerular filtration. Detachment of podocytes from the glomerular basement membrane precedes most glomerular diseases. However, little is known about the regulation of podocyte adhesion in vivo. Thus, we systematically screened for podocyte-specific focal adhesome (FA) components, using genetic reporter models in combination with iTRAQ-based mass spectrometry. This approach led to the identification of FERM domain protein EPB41L5 as a highly enriched podocyte-specific FA component in vivo. Genetic deletion of Epb41l5 resulted in severe proteinuria, detachment of podocytes, and development of focal segmental glomerulosclerosis. Remarkably, by binding and recruiting the RhoGEF ARGHEF18 to the leading edge, EPB41L5 directly controls actomyosin contractility and subsequent maturation of focal adhesions, cell spreading, and migration. Furthermore, EPB41L5 controls matrix-dependent outside-in signaling by regulating the focal adhesome composition. Thus, by linking extracellular matrix sensing and signaling, focal adhesion maturation, and actomyosin activation EPB41L5 ensures the mechanical stability required for podocytes at the kidney filtration barrier. Finally, a diminution of EPB41L5-dependent signaling programs appears to be a common theme of podocyte disease, and therefore offers unexpected interventional therapeutic strategies to prevent podocyte loss and kidney disease progression

Genome-Wide association study (GWAS) for growth rate and age at sexual maturation in atlantic salmon (Salmo salar)

Early sexual maturation is considered a serious drawback for Atlantic salmon aquaculture as it retards growth, increases production times and affects flesh quality. Although both growth and sexual maturation are thought to be complex processes controlled by several genetic and environmental factors, selection for these traits has been continuously accomplished since the beginning of Atlantic salmon selective breeding programs. In this genome-wide association study (GWAS) we used a 6.5K single-nucleotide polymorphism (SNP) array to genotype ∼480 individuals from the Cermaq Canada broodstock program and search for SNPs associated with growth and age at sexual maturation. Using a mixed model approach we identified markers showing a significant association with growth, grilsing (early sexual maturation) and late sexual maturation. The most significant associations were found for grilsing, with markers located in Ssa10, Ssa02, Ssa13, Ssa25 and Ssa12, and for late maturation with markers located in Ssa28, Ssa01 and Ssa21. A lower level of association was detected with growth on Ssa13. Candidate genes, which were linked to these genetic markers, were identified and some of them show a direct relationship with developmental processes, especially for those in association with sexual maturation. However, the relatively low power to detect genetic markers associated with growth (days to 5 kg) in this GWAS indicates the need to use a higher density SNP array in order to overcome the low levels of linkage disequilibrium observed in Atlantic salmon before the information can be incorporated into a selective breeding program

The Role of IQ and Social Skills in Coping With Uncertainty in 7- to 11-Year-Old Children

Abstract. Most feedback we receive or give is correct (deterministic feedback), though a small fraction can be wrong for various reasons. Children need to cope with receiving some portion of wrong feedback (stochastic feedback). It is still unknown if better social functioning and communication skills or outstanding intelligence (IQ) or chronological age support children in the coping process. We tested a sample of 7-‍, 9-‍, and 11-year-old children (N = 60) who deduced a sequence of four left and right button presses from a red and green stochastic feedback signal that was wrong in 15 % of the trials. Children performed worse with stochastic than with deterministic feedback but improved in the repeated trials, especially after receiving positive feedback about whether true or false. Controlling for IQ improved and confirmed these effects, while social and communicative competence explained little or no variance

Guided wave based structural health monitoring of piping systems

In the European project SAFE PIPES guided elastic waves in the frequency range between 100 and 250 kHz, generated and detected by appropriate transducer arrays, are used to monitor the structural integrity of industrial piping systems by comparing the actual state of the pipe with a predefined reference state. In the present paper, theoretical, numerical, and experimental investigations are combined to study guided wave propagation and wave interaction with relevant defects in detail. Based on these findings, a guided wave based multi-channel SHM system is designed and applied for monitoring of crack-like defects in steel pipes. The first results reveal that guided wave based SHM in the kHz frequency regime has great potential for online monitoring of piping systems. It is able to combine imaging techniques with long range detection capabilities and therefore closes the gap between high-frequency NDE on the one hand and low-frequency vibration analysis on the other hand