Developmental changes in the association between approximate number representations and addition skills in elementary school children

The approximate number system (ANS) is assumingly related to mathematical learning but evidence supporting this assumption is mixed. The inconsistent findings might be attributed to the fact that different measures have been used to assess the ANS and mathematical skills. Moreover, associations between the performance on a measure of the ANS and mathematical skills may be discontinuous, i.e., stronger for children with lower math scores than for children with higher math scores, and may change with age. The aim of the present study was to examine the development of the ANS and arithmetic skills in elementary school children and to investigate how the relationship between the ANS and arithmetic skills develops. Individual markers of children's ANS (internal Weber fractions and mean reaction times in a non-symbolic numerical comparison task) and addition skills were assessed in their first year of school and 1 year later. Children showed improvements in addition performance and in the internal Weber fractions, whereas mean reaction times in the non-symbolic numerical comparison task did not change significantly. While children's addition performance was associated with the internal Weber fractions in the first year, it was associated with mean reaction times in the non-symbolic numerical comparison task in the second year. These associations were not found to be discontinuous and could not be explained by individual differences in reasoning, processing speed, or inhibitory control. The present study extends previous findings by demonstrating that addition performance is associated with different markers of the ANS in the course of development

Individual differences in children’s early strategy behavior in arithmetic tasks

As demonstrated by the Overlapping Waves Model (Siegler, 1996), children’s strategy use in arithmetic tasks is variable, adaptive, and changes gradually with age and experience. In this study, first grade elementary school children (n = 73), who scored high, middle, or low in a standardized scholastic mathematic achievement test, were confronted with different arithmetic tasks (simple addition, e.g., 3 + 2, simple subtraction, e.g., 7 – 2, and more advanced addition, e.g., 7 + 9) to evoke different calculation strategies. Video analysis and children’s self-report were used to identify individual strategy behavior. In accordance with the Overlapping Waves Model, children in all achievement groups showed variable and multiple strategy usage and adapted their behavior to the tasks of the different categories. We demonstrated that not only low achievers differed from normal achievers but also that high achievers exhibited a unique pattern of strategy behavior in early mathematics

Spatial representations of numbers and letters in children

Different lines of evidence suggest that children's mental representations of numbers are spatially organized in form of a mental number line. It is, however, still unclear whether a spatial organization is specific for the numerical domain or also applies to other ordinal sequences in children. In the present study, children (n = 129) aged 8–9 years were asked to indicate the midpoint of lines flanked by task-irrelevant digits or letters. We found that the localization of the midpoint was systematically biased toward the larger digit. A similar, but less pronounced, effect was detected for letters with spatial biases toward the letter succeeding in the alphabet. Instead of assuming domain-specific forms of spatial representations, we suggest that ordinal information expressing relations between different items of a sequence might be spatially coded in children, whereby numbers seem to convey this kind of information in the most salient way

Gender differences in children’s math self-concept in the first years of elementary school

In the course of elementary school children start to develop an academic self-concept reflecting their motivation, thoughts, and feelings about a specific domain. For the domain of mathematics, gender differences can emerge which are characterized by a less pronounced math self-concept for girls. However, studies are rather sparse regarding the early years of elementary school education, hence, the point in time when such gender differences emerge yet remains a matter of debate. In our study, we found that the math self-concept of elementary school children (n = 81) declined from first to second grade. While no differences in math achievement were observed between girls and boys, it became apparent that girls’ math self-concept was already less pronounced than the math self-concept of boys in the first years of elementary school. Our findings emphasize the importance of considering such gender differences even at the beginning of school education

Grey matter alterations co-localize with functional abnormalities in developmental dyslexia : an ALE meta-analysis

The neural correlates of developmental dyslexia have been investigated intensively over the last two decades and reliable evidence for a dysfunction of left-hemispheric reading systems in dyslexic readers has been found in functional neuroimaging studies. In addition, structural imaging studies using voxel-based morphometry (VBM) demonstrated grey matter reductions in dyslexics in several brain regions. To objectively assess the consistency of these findings, we performed activation likelihood estimation (ALE) meta-analysis on nine published VBM studies reporting 62 foci of grey matter reduction in dyslexic readers. We found six significant clusters of convergence in bilateral temporo-parietal and left occipito-temporal cortical regions and in the cerebellum bilaterally. To identify possible overlaps between structural and functional deviations in dyslexic readers, we conducted additional ALE meta-analyses of imaging studies reporting functional underactivations (125 foci from 24 studies) or overactivations (95 foci from 11 studies ) in dyslexics. Subsequent conjunction analyses revealed overlaps between the results of the VBM meta-analysis and the meta-analysis of functional underactivations in the fusiform and supramarginal gyri of the left hemisphere. An overlap between VBM results and the meta-analysis of functional overactivations was found in the left cerebellum. The results of our study provide evidence for consistent grey matter variations bilaterally in the dyslexic brain and substantial overlap of these structural variations with functional abnormalities in left hemispheric regions

Differences in Counting Skills Between Chinese and German Children Are Accompanied by Differences in Processing of Approximate Numerical Magnitude Information

Human beings are supposed to possess an approximate number system (ANS) dedicated to extracting and representing approximate numerical magnitude information as well as an object tracking system (OTS) for the rapid and accurate enumeration of small sets. It is assumed that the OTS and the ANS independently contribute to the acquisition of more elaborate numerical concepts. Chinese children have been shown to exhibit more elaborate numerical concepts than their non-Chinese peers, but it is still an open question whether similar cross-national differences exist with regard to the underlying systems, namely the ANS and the OTS. In the present study, we investigated this question by comparing Chinese and German preschool children with regard to their performance in a non-symbolic numerical magnitude comparison task (assessing the ANS) and in an enumeration task (assessing the OTS). In addition, we compared children’s counting skills. To ensure that possible between-group differences could not be explained by differences in more general performance factors, we also assessed children’s reasoning ability and processing speed. Chinese children showed a better counting performance and a more accurate performance in the non-symbolic numerical magnitude comparison task. These differences in performance could not be ascribed to differences in reasoning abilities and processing speed. In contrast, Chinese and German children did not differ significantly in the enumeration of small sets. The superior counting performance of Chinese children was thus found to be reflected in the ANS but not in the OTS

Veränderung der Leseleistung von Kindern mit Leseschwierigkeiten durch Ausblenden des zu lesenden Textes

The Acceleration Phenomenon (AP) has been demonstrated by studies showing that reading rate and comprehension improvements can be induced by a fading procedure, erasing text based on the previously measured individual\u27s fastest reading rate. However, whether or not reading enhancements can also be observed through slow fading rates has not been explored in detail. The focus of the present study was hence to investigate whether a fading rate slower than the individual\u27s self-paced reading rate can also induce AP effects which positively affect reading performance. A sample of 34 third graders with reading difficulties was selected to participate in this study. Two slow fading conditions were implemented: condition in which text was faded out 40 % slower and a condition where text was faded out 70 % slower than the self-paced reading rate. The 40 % reduced fading manipulation significantly enhanced children\u27s reading rate and comprehension scores compared to their self-paced reading performance. The 70 % reduced fading manipulation also resulted in slightly faster reading rates but not in better comprehension. The present data suggests that the fading rate does not need to be set at a rate at the upper limit of participants\u27 reading performance. Still, it seems highly relevant to consider which rate is applied, as a fading manipulation that is too slow did not result in comprehension improvements. Implications for the pedagogical applicability and possible future research foci are discussed. (DIPF/Orig.)Studien zum Acceleration Phenomenon (AP) konnten zeigen, dass Probanden ihre Lesegeschwindigkeit und ihr Leseverständnis verbessern können, wenn präsentierter Text beim Lesen in der schnellsten individuellen Lesezeit ausgeblendet wird. Ob diese Leseverbesserungen auch erzeugt werden können, wenn die Ausblendegeschwindigkeit langsamer als die individuelle Lesegeschwindigkeit ist, wurde bisher nicht untersucht. Mit Hilfe der Untersuchung einer Stichprobe von 34 Drittklässlern mit Leseschwierigkeiten sollte in dieser Studie überprüft werden, welchen Einfluss langsames Ausblenden auf den Leseprozess hat. Zwei Bedingungen werden eingeführt: eine, in welcher der Text um 40 % langsamer, und eine zweite, in welcher der Text um 70 % langsamer als die normale Lesegeschwindigkeit ausgeblendet wurde. In der um 40 % verlangsamten Bedingung verbesserten sich die Kinder signifikant in ihrer Lesegeschwindigkeit sowie in ihrem Leseverständnis. Die um 70 % verlangsamte Bedingung erzeugte zwar Verbesserungen in der Lesegeschwindigkeit, jedoch nicht im Leseverständnis. Die Ergebnisse verdeutlichen, dass die Ausblendegeschwindigkeit nicht schneller sein muss als die individuelle Lesegeschwindigkeit um positive Leseverbesserungen zu erzielen. Weiterhin konnte gezeigt werden, dass die Ausblendegeschwindigkeit große Relevanz hat, da keine Leseverständnisverbesserungen in der um 70 % verlangsamten Bedingung gefunden werden konnten. Die Anwendbarkeit der Befunde für die pädagogische Praxis sowie mögliche zukünftige Forschungsschwerpunkte werden in der Diskussion aufgegriffen. (DIPF/Orig.

Is Animal Cruelty or Abolitionist Messaging More Effective: A Reanalysis

This document presents a reanalysis of the data and conclusions reported on September 20, 2015, by Humane League Labs in the blog post titled "Is animal cruelty or abolitionist messaging more effective?" and the accompanying report titled "Report: Is Animal Cruelty, Environmental or Purity (“Abolitionist”) Messaging More Effective At Inspiring People To Change Their Diet?" The study compared the effect of three animal advocacy messages on participants’ self-reported intention to change their animal product consumption. Our reanalysis supports the original report’s conclusion that a message focussing on the cruelty animals endure in factory farming systems is more effective than a message focussing on animal rights and moral consistency. In contrast to the original report, our reanalysis did not find significant differences between the message focussing on cruelty and a message focussing on the environmental impact of meat consumption. Results for the comparison of the environmental message with the animal rights messages were mixed. Overall, we recommend interpreting the findings with caution as there are several serious flaws in the design of the study

The impact of reading material\u27s lexical accessibility on text fading effects in children\u27s reading performance

The acceleration phenomenon (AP) is defined by improvements in reading speed and reading comprehension, induced by an artificial text fading procedure corresponding to the previously determined fastest individual reading rate. Recent results, however, indicated that fading that is slower than the self-paced reading rate can produce comparable reading enhancements. As reading performance can be strongly influenced by the reading material, this study aimed at investigating to which extent reading enhancements induced by text fading depend on the reading material\u27s characteristics. We confronted 39 German third graders with a previously utilized text fading procedure, which was slower than their self-paced reading rate. Included text varied regarding to the lexical accessibility (LA), representing how well information can be accessed from the mental lexicon. Children\u27s reading rates increased statistically significant due to text fading for all LA levels. However, reading comprehension was sensitive to the text material\u27s characteristics: Reading comprehension enhancements were observable for easily accessible reading material, but not for material with intermediate or difficult levels of LA. Material that was difficult to retrieve from the mental lexicon even resulted in reduced reading comprehension in the fading condition. Possible influences on immediate lexical access, the impact of working memory capacity and implications for future AP research are discussed

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

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