Relations among fluid intelligence, sensory discrimination and working memory in middle to late childhood – A latent variable approach

Two factors that have been suggested as key in explaining individual differences in fluid intelligence are working memory and sensory discrimination ability. A latent variable approach was used to explore the relative contributions of these two variables to individual differences in fluid intelligence in middle to late childhood. A sample of 263 children aged 7–12 years was examined. Correlational analyses showed that general discrimination ability (GDA)and working memory (WM) were related to each other and to fluid intelligence. Structural equation modeling showed that within both younger and older age groups and the sample as a whole, the relation between GDA and fluid intelligence could be accounted for by WM. While WM was able to predict variance in fluid intelligence above and beyond GDA, GDA was not able to explain significant amounts of variance in fluid intelligence, either in the whole sample or within the younger or older age group. We concluded that compared to GDA, WM should be considered the better predictor of individual differences in fluid intelligence in childhood. WM and fluid intelligence, while not being separable in middle childhood, develop at different rates, becoming more separable with age

Inhibition and behavioral self-regulation: An inextricably linked couple in preschool years

A modified version of the flanker task was used to investigate how children deal with increasing inhibitory control demands. Additional variables such as age, cue salience and behavioral regulation were also considered in the present research. Preschoolers and first graders alike, showed a performance decline once inhibitory control demands increased. When taking behavioral regulation skills into account, an age-related interaction effect was found: Compared to their peers with high behavioral regulation skills, preschoolers with low to moderate behavioral regulation skills showed a weaker performance when faced with increased inhibitory control demands. No such effects were found for first graders. The results suggest that in particular in preschool years inhibition and behavioral regulation are highly intertwined

Sustained attention and its relationship to fluid intelligence and working memory in children

Understanding individual differences in intelligence remains an interesting research question, even with more than a century of empirical research and large numbers of models and theories. We know that working memory (WM) is able to explain substantial amounts of variance in fluid intelligence in both children and adults, but we also know that it is not the only predictor of intelligence. There are many other information-processing mechanisms that have been studied. Results in adult samples seem to indicate that sustained attention—the ability to maintain attention on a specific task over an extended period of time—is strongly related to fluid intelligence. There is little research on this topic in childhood, but the available data seems to converge with results from adult samples. The aim of the present study was to assess sustained attention and its relationship to fluid intelligence and WM in children. Additionally, we wanted to explore whether sustained attention contributes to the prediction of intelligence over and above WM. A sample of 125 ten-year olds was assessed using tests of fluid intelligence, sustained attention and WM. The results showed that, as expected, WM and fluid intelligence were significantly related. Surprisingly however, sustained attention was not related to fluid intelligence or WM. Using results from previous studies and theoretical considerations, we concluded that sustained attention may not be directly related to fluid intelligence in childhood, but rather that it may be a more distal factor influencing information processing in more unstructured learning situations and hence impacting academic achievement

The development of inductive reasoning under consideration of the effect due to test speededness

Measures of inductive reasoning are frequently used as proxy of a child’s cognitive develop-ment. Unfortunately, a reasoning scale might be affected by speededness introduced by li-mited testing time. As a result, the scale might be heterogeneous and its correlation with age is hard to interpret. Here we investigated the development of inductive reasoning when a possible bias by the effect of speededness is controlled for. In 250 children, ranging in age from 8;0 to 12;8 years, inductive reasoning assessed with the Culture Fair Test 20-R (CFT 20-R) increased with age. The effect of speededness was identified in all four CFT 20-R sub-test and was also related to age indicating increasing processing speed with higher age. After controlling for the effect of speededness, the relation between age and inductive rea-soning was still observed but substantially decreased. Consequences of these results for the description of inductive reasoning data obtained with time-limited tests and for develop-mental studies on the interplay between age, inductive reasoning and speed of information processing are discussed.scussed

Individual differences in working memory capacity explain the relationship between general discrimination ability and psychometric intelligence

The close association between psychometric intelligence and general discrimination ability (GDA), conceptualized as latent variable derived from performance on different sensory discrimination tasks, is empirically well-established but theoretically widely unclear. The present study contrasted two alternative explanations for this association. The first explanation is based on what Spearman (1904) referred to as a central function underlying this relationship in the sense of the g factor of intelligence and becoming most evident in GDA. In this case, correlations between different aspects of cognitive abilities, such as working memory (WM) capacity, and psychometric intelligence should be mediated by GDA if their correlation is caused by g. Alternatively, the second explanation for the relationship between psychometric intelligence and GDA proceeds from fMRI studies which emphasize the role of WM functioning for sensory discrimination. Given the well-known relationship between WM and psychometric intelligence, the relationship between GDA and psychometric intelligence might be attributed to WM. The present study investigated these two alternative explanations at the level of latent variables. In 197 young adults, a model in which WM mediated the relationship between GDA and psychometric intelligence described the data better than a model in which GDA mediated the relationship between WM and psychometric intelligence. Moreover, GDA failed to explain portions of variance of psychometric intelligence above and beyond WM. These findings clearly support the view that the association between psychometric intelligence and GDA must be understood in terms of WM functioning