Intellectual growth in children as a function of domain specific and domain general working memory subgroups

This study examined whether children's growth on measures of fluid (Raven Colored Progressive Matrices) and crystallized (reading and math achievement) intelligence was attributable to domain-specific or domain-general functions of working memory (WM). A sample of 290 elementary school children was tested on measures of intelligence across three testing waves. Two methods, a hierarchical factor model predicting latent growth and a double dissociation design comparing children divided into high and low performers, tested whether general and/or specific components accounted for performance on intelligence measures. A general domain model for the total sample provided the best fit for latent growth on all measures. Further, the lack of a significant WM subgroup × domain interaction suggested that a general WM system underlies the individual differences on measures of fluid and crystallized intelligence. Overall, the findings support a domain-general view of WM capacity on intelligence measures in children, but also suggest that domain specific storage systems may come into play on isolated measures.     

The relationship between intelligence,working memory,academic self-esteem,and academic achievement

Academic achievement is crucial for life and long-term outcomes. The aim of the present study is to examine the joint role of cognitive (intelligence and working memory) and non-cognitive (academic self-esteem) factors in predicting academic achievement (mathematics and reading literacy) in a sample of Italian sixth and eighth graders. The results showed that within the cognitive factors considered, intelligence was the best predictor of achievement. As regards to non-cognitive factors, academic self-esteem was effective at predicting achievement after controlling for cognitive measures. Academic self-esteem was also found to have an indirect effect, mediated by intelligence, on academic achievement. Both theoretical and practical implications of the present results are discussed.     

Working memory and fluid intelligence in young children

The present study investigates how working memory and fluid intelligence are related in young children and how these links develop over time. The major aim is to determine which aspect of the working memory system—short-term storage or cognitive control—drives the relationship with fluid intelligence. A sample of 119 children was followed from kindergarten to second grade and completed multiple assessments of working memory, short-term memory, and fluid intelligence. The data showed that working memory, short-term memory, and fluid intelligence were highly related but separate constructs in young children. The results further showed that when the common variance between working memory and short-term memory was controlled, the residual working memory factor manifested significant links with fluid intelligence whereas the residual short-term memory factor did not. These findings suggest that in young children cognitive control mechanisms rather than the storage component of working memory span tasks are the source of their link with fluid intelligence.     

Working memory in multilingual children: Is there a bilingual effect?

This research investigates whether early childhood bilingualism affects working memory performance in 6- to 8-year-olds, followed over a longitudinal period of 3 years. The study tests the hypothesis that bilinguals might exhibit more efficient working memory abilities than monolinguals, potentially via the opportunity a bilingual environment provides to train cognitive control by combating interference and intrusions from the non-target language. A total of 44 bilingual and monolingual children, matched on age, sex, and socioeconomic status, completed assessments of working memory (simple span and complex span tasks), fluid intelligence, and language (vocabulary and syntax). The data showed that the monolinguals performed significantly better on the language measures across the years, whereas no language group effect emerged on the working memory and fluid intelligence tasks after verbal abilities were considered. The study suggests that the need to manage several language systems in the bilingual mind has an impact on children's language skills while having little effects on the development of working memory.     

Personality predicts prospective memory task performance: an adult lifespan study

Do interindividual differences in prospective memory task performance reflect individual differences in personality and lifestyle? Do the cognitive abilities known to change with age retain their power to predict episodic prospective memory task performance after controlling for personality and lifestyle variables, and do personality and lifestyle variables offer predictive power apart from that provided by cognitive ability measures? To answer these questions, we conducted a study with community‐living healthy individuals (n= 141) between 18 and 81 years of age. They completed three different episodic prospective memory tasks – two laboratory tasks and one field task – as well as various measures of personality, lifestyle, and cognitive ability. The results indicated that personality and lifestyle reliably predicted who will succeed and who will fail on all three episodic prospective memory tasks. Conscientiousness predicted performance on two of the prospective memory tasks; socially prescribed perfectionism and neuroticism each predicted performance on one of the prospective memory tasks. Cognitive ability predicted performance on one of the laboratory prospective memory tasks but not on the other two prospective memory tasks. After we controlled for individual differences in personality and lifestyle variables, cognitive ability was no longer able to predict performance on the laboratory prospective memory task. By contrast, controlling for cognitive ability had no influence on the predictive power of the personality and lifestyle variables.     

Gains in fluid intelligence after training non-verbal reasoning in 4-year-old children: a controlled, randomized study

Fluid intelligence (Gf) predicts performance on a wide range of cognitive activities, and children with impaired Gf often experience academic difficulties. Previous attempts to improve Gf have been hampered by poor control conditions and single outcome measures. It is thus still an open question whether Gf can be improved by training. This study included 4-year-old children (N = 101) who performed computerized training (15 min/day for 25 days) of either non-verbal reasoning, working memory, a combination of both, or a placebo version of the combined training. Compared to the placebo group, the non-verbal reasoning training group improved significantly on Gf when analysed as a latent variable of several reasoning tasks. Smaller gains on problem solving tests were seen in the combination training group. The group training working memory improved on measures of working memory, but not on problem solving tests. This study shows that it is possible to improve Gf with training, which could have implications for early interventions in children.     

Can fluid intelligence be reduced to ‘simple’ short-term storage?

Much is written regarding the associations between human intelligence and cognition. However, it is unusual to find comprehensive studies. Here twenty four measures tapping eight cognitive abilities and skills are considered for assessing a sample of one hundred and eighty five young adults. The simultaneous relationships among fluid, crystallized, and spatial intelligence, along with short-term memory, working memory capacity, executive updating, attention, and processing speed are analyzed using a latent-variable approach. The key findings show that (a) short-term storage, working memory, and updating are hardly distinguishable, and (b) fluid intelligence is near-perfectly correlated with these three cognitive functions. It is concluded that this nuclear intelligence component can be largely identified with basic and general short-term storage processes, namely, encoding, maintenance, and retrieval.     

Construct validity and age sensitivity of prospective memory

We administered four prospective memory tasks to 330 adults between 18 and 89 years of age to investigate the relationship among the measures of performance in the four tasks, as well as the relationship of the prospective memory measures to age, other cognitive abilities, and noncognitive factors. The four prospective memory variables were found to exhibit both convergent and discriminant validity, indicating that prospective memory ability appears to represent a distinct dimension of individual differences. The prospective memory construct was significantly related to other cognitive abilities, such as executive functioning, fluid intelligence, episodic memory, and perceptual speed, but it was only weakly related to self-ratings of (primarily retrospective) memory and to personality traits. Although a substantial proportion of the age-related variance on the prospective memory construct was shared with other cognitive abilities, we also found some evidence of unique, statistically independent, age-related influences on prospective memory.     

Networks of self-defining memories as a contributing factor to emotional openness

Emotional openness is characterised by a capacity to tolerate threatening self-relevant material and an interest towards new emotional situations. We investigated how specific networks of memories could be an important contributing factor to emotional openness. At Phase 1, participants completed measures of personality traits and emotional intelligence, described a self-defining memory, provided other memories associated with it, and rated the valence of each of their memories. A score assessing the complexity of this memory network, comprising the number of memories reported and their valence diversity, was created. Two weeks later, in laboratory, participants watched an anxiety-inducing film and took part in an interview assessing their emotional openness to the film. They completed a cognitive task before and after the film to measure ego depletion. Controlling for traits and emotional intelligence, memory network complexity was positively associated with emotional openness and negatively with ego depletion. The mental organisation of self-defining memories thus appears to be a critical factor contributing to emotional openness.     

Beyond cognitive ability: Improving the prediction of performance

New measures of practical intelligence and personality traits were assessed for their ability to improve the prediction of performance beyond cognitive ability. Measures of practical intelligence from the newly developed Constructive Thinking Inventory and traits measuring emotional stability and expedience were used as independent variables in regression analyses predicting academic performance, training performance and leadership ratings of 86 student leaders. The constructive thinking scales added significantly to the prediction of academic performance, beyond measures of cognitive ability. Constructive thinking also accounted for unique variance predicting training performance and leadership ratings. Personality traits were unrelated to performance or leadership.     

The unique contributions of the facilitation of procedural memory and working memory to individual differences in intelligence

Individual differences in working memory account for a substantial portion of individual differences in complex cognitive processes (e.g., comprehension) and fluid intelligence. However, a large portion of the variance in fluid intelligence and comprehension is unexplained. The current investigation was conducted to evaluate whether individual differences in the facilitation of procedural memory accounts for unique variance in intelligence not accounted for by working memory. To measure variability in the facilitation of procedural memory, we used a task that required participants to first classify exemplars of two categories; facilitation was then operationalized by subsequent improvements in the speed of classifying new exemplars from those categories (i.e., an operation-specific memory procedure). Three measures of each focal construct (facilitation in procedural memory, working memory, comprehension and fluid intelligence) were administered to 256 participants. We used structural equation modeling to examine the relationships among these latent variables. Working memory did account for variance in fluid intelligence and comprehension, but most important, individual differences in facilitation of procedural memory accounted for unique variance in fluid intelligence and comprehension.     

Executive functioning and memory as potential mediators of the episodic feeling-of-knowing accuracy

The study focused on the cognitive determinants of the accuracy of feeling-of-knowing (FOK) judgments made on episodic memory information. An individual differences approach was used on a sample of healthy older adults assessed on an episodic FOK task and on several neuropsychological measures. At a global level of analysis of FOK accuracy, the contributions of four general cognitive processes--episodic memory, executive functioning, fluid intelligence and processing speed--were examined concurrently. Stepwise regression analyses showed that executive functioning accounted for the major part of variance on FOK accuracy, followed by a significant contribution of episodic memory. After controlling for executive and memory involvement, fluid intelligence and processing speed no longer accounted for significant variance. At a more detailed level of analysis of FOK accuracy, the contributions of three specific executive processes--shifting, updating and inhibition--were assessed. The results revealed shifting function as the primary executive process engaged in the production of accurate FOK judgments in episodic memory. Some hypotheses are put forward to better understand the central role of executive functioning in the production of accurate FOK judgments.     

Working Memory Capacity as Executive Attention

Performance on measures of working memory (WM) capacity predicts performance on a wide range of real-world cognitive tasks. I review the idea that WM capacity (a) is separable from short-term memory, (b) is an important component of general fluid intelligence, and (c) represents a domain-free limitation in ability to control attention. Studies show that individual differences in WM capacity are reflected in performance on antisaccade, Stroop, and dichotic-listening tasks. WM capacity, or executive attention, is most important under conditions in which interference leads to retrieval of response tendencies that conflict with the current task.     

Decomposing the relationship between cognitive functioning and self-referent memory beliefs in older adulthood: what’s memory got to do with it?

With advancing age, episodic memory performance shows marked declines along with concurrent reports of lower subjective memory beliefs. Given that normative age-related declines in episodic memory co-occur with declines in other cognitive domains, we examined the relationship between memory beliefs and multiple domains of cognitive functioning. Confirmatory bi-factor structural equation models were used to parse the shared and independent variance among factors representing episodic memory, psychomotor speed, and executive reasoning in one large cohort study (Senior Odyssey, N = 462), and replicated using another large cohort of healthy older adults (ACTIVE, N = 2802). Accounting for a general fluid cognitive functioning factor (comprised of the shared variance among measures of episodic memory, speed, and reasoning) attenuated the relationship between objective memory performance and subjective memory beliefs in both samples. Moreover, the general cognitive functioning factor was the strongest predictor of memory beliefs in both samples. These findings are consistent with the notion that dispositional memory beliefs may reflect perceptions of cognition more broadly. This may be one reason why memory beliefs have broad predictive validity for interventions that target fluid cognitive ability.     

Working memory resources in young children with mathematical difficulties

Kyttälä, M., Aunio, P. & Hautamäki, J. (2010). Working memory resources in young children with mathematical difficulties. Scandinavian Journal of Psychology, 51 , 1–15.
Working memory (WM) ( Baddeley, 1986, 1997 ) is argued to be one of the most important cognitive resources underlying mathematical competence ( Geary, 2004 ). Research has established close links between WM deficits and mathematical difficulties. This study investigated the possible deficits in WM, language and fluid intelligence that seem to characterize 4- to 6-year-old children with poor early mathematical skills before formal mathematics education. Children with early mathematical difficulties showed poor performance in both verbal and visuospatial WM tasks as well as on language tests and a fluid intelligence test indicating a thoroughly lower cognitive base. Poor WM performance was not moderated by fluid intelligence, but the extent of WM deficits was related to language skills. The educational implications are discussed.     

Complex working memory span tasks and higher-order cognition: A latent-variable analysis of the relationship between processing and storage

Complex span tasks, assumed by many to measure an individual's working memory capacity, are predictive of several aspects of higher-order cognition. However, the underlying cause of the relationships between “processing-and-storage” tasks and cognitive abilities is still hotly debated nearly 30 years after the tasks were first introduced. The current study utilised latent constructs across verbal, numerical, and spatial content domains to examine a number of questions regarding the predictive power of complex span tasks. In particular, the relations among processing time, processing accuracy, and storage accuracy from the complex span tasks were examined, in combination with their respective relationships with fluid intelligence. The results point to a complicated pattern of unique and shared variance among the constructs. Implications for various theories of working memory are discussed.     

Variations in working memory capacity predict individual differences in general learning abilities among genetically diverse mice

Up to 50% of an individuals' performance across a wide variety of distinct cognitive tests can be accounted for by a single factor (i.e., "general intelligence"). Despite its ubiquity, the processes or mechanisms regulating this factor are a matter of considerable debate. Although it has been hypothesized that working memory may impact cognitive performance across various domains, tests have been inconclusive due to the difficulty in isolating working memory from its overlapping operations, such as verbal ability. We address this problem using genetically diverse mice, which exhibit a trait analogous to general intelligence. The general cognitive abilities of CD-1 mice were found to covary with individuals' working memory capacity, but not with variations in long-term retention. These results provide evidence that independent of verbal abilities, variations in working memory are associated with general cognitive abilities, and further, suggest a conservation across species of mechanisms and/or processes that regulate cognitive abilities.     

工作记忆、加工速度与流体智力的发展

近几年有关认知发展心理机制的研究成为一个认知发展领域一个颇引人注目的内容．这些研究探讨了年龄、工作记忆、加工速度与流体智力之间的关系。研究发现．在流体智力的发展过程中,工作记忆可能比加工速度发挥着更直接、更一般的作用,而加工速度则对工作记忆的发展起直接调节作用。     

Assessing the predictive validity of emotional intelligence

Emotional intelligence has become a fashionable topic in the popular press, and has been heralded as an effective predictor of successful performance. However, little empirical evidence has borne out these claims. The present study was conducted in order to determine the relationship of emotional intelligence, cognitive ability, and personality with academic achievement. Emotional intelligence was assessed using the EQ-i (total EQ-i score and five EQ-i composite factor scores). Both cognitive ability and personality (in terms of extraversion and self control) were significantly associated with academic achievement. None of the EQ-i factor scores, nor the total EQ-i score, was significantly related to academic achievement.     

Similarities and differences between mind-wandering and external distraction: A latent variable analysis of lapses of attention and their relation to cognitive abilities

The current study examined the extent to which task-unrelated thoughts represent both vulnerability to mind-wandering and susceptibility to external distraction from an individual difference perspective. Participants performed multiple measures of attention control, working memory capacity, and fluid intelligence. Task-unrelated thoughts were assessed using thought probes during the attention control tasks. Using latent variable techniques, the results suggested that mind-wandering and external distraction reflect distinct, yet correlated constructs, both of which are related to working memory capacity and fluid intelligence. Furthermore, the results suggest that the common variance shared by mind-wandering, external distraction, and attention control is what primarily accounts for their relation with working memory capacity and fluid intelligence. These results support the notion that lapses of attention are strongly related to cognitive abilities.