Working memory components and intelligence in children

The Relationship between Executive Functions, Working Memory, and Intelligence in Kindergarten Children

Executive functions (EF), working memory (WM), and intelligence are closely associated, but distinct constructs. What underlies the associations between these constructs, especially in childhood, is not well understood. In this pre-registered study, along with the traditional aggregate accuracy and RT-based measures of EF, we investigated post-error slowing (PES) in EF as a manifestation of metacognitive processes (i.e., monitoring and cognitive control) in relation to WM and intelligence. Thereby, we aimed to elucidate whether these metacognitive processes may be one underlying component to explain the associations between these constructs. We tested kindergarten children (M_age = 6.4 years, SD_age = 0.3) in an EF, WM (verbal and visuospatial), and fluid (non-verbal) intelligence task. We found significant associations of mainly the inhibition component of EF with fluid intelligence and verbal WM, and between verbal WM and intelligence. No significant associations emerged between the PES in EF and intelligence or WM. These results suggest that in the kindergarten age, inhibition rather than monitoring and cognitive control might be the underlying component that explains the associations between EF, WM, and intelligence.

Effects of working memory training on cognitive and academic abilities in typically developing school-age children

Process-based working memory (WM) training in typically developing children usually leads to short- and long-term improvements on untrained WM tasks. However, results are mixed regarding far transfer to academic and cognitive abilities. Moreover, there is a lack of studies jointly evaluating the different types of transfer, using an adequate design and considering motivational factors. In addition, evidence is needed about how pre-training performance is related to individual differences in training-induced transfer. Therefore, this study aimed to implement and evaluate the efficacy of a computerized process-based WM training in typically developing school-age children. Near and far transfer effects were evaluated both immediately after training and after 6 months, as well as individual differences in training-induced transfer. The sample was composed of 89 typically developing children aged 9-10 years (M = 9.52, SD = 0.30), who were randomized to a WM training group or an active control group. They were evaluated at pre-training, post-training, and follow-up phases with measures of visuospatial and verbal WM, reading comprehension, math computation, and fluid intelligence. Results showed that the training group significantly improved performance in verbal WM and fluid intelligence compared to the active control group, immediately after training and after 6 months. Trained children with lower initial performance in verbal WM or fluid intelligence showed greater transfer gains. No group differences were found in motivational factors. Findings of this study suggest that process-based WM training may promote transfer to cognitive abilities and lead to compensation effects of individual differences in typically developing school-age children.

A Cluster Randomized Trial of Promoting Alternative Thinking Strategies (PATHS®) With Swedish Preschool Children

The preschool edition of Promoting Alternative THinking Strategies (PATHS^®) is a school-based, teacher implemented universal intervention developed in the United States designed to promote social emotional competence (SEC) in children as a foundation for improved mental health. PATHS is delivered as a curriculum and it is based on theories and research regarding SEC, brain development, and optimal school environments. A majority of children in Sweden attend preschool, which is government-subsidized and follows a national curriculum focusing on both academic and social emotional learning. However, there is not so much focus on formal instruction nor manual-based lessons. The purpose of this study was to assess the short-term (pre- to post-test) effects of PATHS in the Swedish preschool setting. Using a two-wave cluster randomized trial with multi-method and informant assessment (N = 285 4 and 5-year-old Swedish children; n = 145 wait-list control; n = 140 intervention; K = 26 preschools; k = 13 intervention; k = 13 control) we assessed changes in child emotional knowledge, emotional awareness, social problem solving, prosocial play, inhibitory control, and working memory using structural equation modeling (SEM). We included schools with at least one classroom of 4–5-year-old children from three municipalities. We excluded open preschools, parent cooperative preschools, and family day homes. After random assignment, schools were informed of condition assignment. Research team members were not blind to assignment. We hypothesized that relative to children in control schools, children in intervention schools would evidence improvements in social emotional competence as well as other outcomes. Children in PATHS, relative to children in the control, evidenced improvements in working memory and prosocial play, but also showed an increase in hyperactive behaviors. Girls in PATHS, relative to girls in the control, showed improvement in emotional knowledge and reduced anxiety. These results are considered in light of efforts to promote positive development and mental health. The trial registration number at ClinicalTrials.gov is NCT04512157. Main funding was from Swedish Council for Working Life and Social Research, the Swedish Research Council, Formas, and VINNOVA (dnr: 259-2012-71).

Cognitive and Emotional Profiles of CU Traits and Disruptive Behavior in Adolescence: a Prospective Study

In this study we followed 82-90 adolescents, 50% boys, from 15 to 16 years, investigating CU traits and disruptive behaviors as predictors of cognitive skills and arousal to emotional pictures. At age 15, CU traits were rated by adolescents and disruptive (aggregated ADHD-ODD-delinquent) behaviors were rated by parents and adolescents. At age 16, executive function, reaction time variability (RTV), IQ and arousal to negative pictures were assessed. The results showed that, with control for disruptive behaviors, CU traits predicted lower RTV, higher IQ and lower arousal to negative pictures. With control for CU traits, disruptive behaviors predicted lower spatial working memory, lower interference control and higher RTV. Our findings are of theoretical and clinical relevance as they point to highly diverging cognitive and emotional profiles of CU traits and disruptive behaviors.

Short-Term Storage and Executive Working Memory Processing Predict Fluid Intelligence in Primary School Children

Working memory (WM) includes short-term storage and executive processing of information. WM has been suggested to be one of the key concepts to explain individual differences in fluid intelligence (Gf). However, only a few studies have investigated the association of the two different aspects of WM in relation to Gf. Furthermore, even fewer studies have included children. Therefore, we first investigated the inter-relations between the WM aspects (verbal and visual-spatial storage, verbal and visual-spatial executive processing). Second, we explored the relation between a general WM factor and Gf. Third, we analyzed the relations between the different WM aspects and Gf while we controlled for common variance among all WM tasks. Nine- to 11-year olds had to solve simple and complex span tasks. Correlations and structural equation modeling techniques were used to examine these relations. Most inter-relations among simple and complex spans were found to be substantial and positive. The general WM factor was related to Gf. Furthermore, after controlling for common variance among all WM tasks, individual differences in verbal storage, visual-spatial storage and verbal processing still uniquely related to Gf. Visual-spatial processing, however, was not related to Gf. Results are discussed in terms of underlying mechanisms.

Visual Working Memory Capacity Can Be Increased by Training on Distractor Filtering Efficiency

It is generally considered that working memory (WM) capacity is limited and that WM capacity affects cognitive processes. Distractor filtering efficiency has been suggested to be an important factor in determining the visual working memory (VWM) capacity of individuals. In the present study, we investigated whether training in visual filtering efficiency (FE) could improve VWM capacity, as measured by performance on the change detection task (CDT) and changes of contralateral delay activity (CDA) (contralateral delay activity) of different conditions, and evaluated the transfer effect of visual FE training on verbal WM and fluid intelligence, as indexed by performance on the verbal WM span task and Raven’s Standard Progressive Matrices (RSPM) test, respectively. Participants were divided into high- and low-capacity groups based on their performance in a CDT designed to test VWM capacity, and then the low-capacity individuals received 20 days of FE training. The training significantly improved the group’s performance in the CDT, and their CDA models of different conditions became more similar with high capacity group, and the effect generalized to improve verbal WM span. These gains were maintained at a 3-month follow-up test. Participants’ RSPM scores were not changed by the training. These findings support the notion that WM capacity is determined, at least in part, by distractor FE and can be enhanced through training.

Predictive model for early math skills based on structural equations

Early math skills are determined by higher cognitive processes that are particularly important for acquiring and developing skills during a child's early education. Such processes could be a critical target for identifying students at risk for math learning difficulties. Few studies have considered the use of a structural equation method to rationalize these relations. Participating in this study were 207 preschool students ages 59 to 72 months, 108 boys and 99 girls. Performance with respect to early math skills, early literacy, general intelligence, working memory, and short-term memory was assessed. A structural equation model explaining 64.3% of the variance in early math skills was applied. Early literacy exhibited the highest statistical significance (β = 0.443, p < 0.05), followed by intelligence (β = 0.286, p < 0.05), working memory (β = 0.220, p < 0.05), and short-term memory (β = 0.213, p < 0.05). Correlations between the independent variables were also significant (p < 0.05). According to the results, cognitive variables should be included in remedial intervention programs.

The Monkey game: A computerized verbal working memory task for self-reliant administration in primary school children

In two studies, the psychometric properties of an online self-reliant verbal working memory task (the Monkey game) for primary school children (6-12 years of age) were examined. In Study 1, children (n = 5,203) from 31 primary schools participated. The participants completed computerized verbal and visual-spatial working memory tasks (i.e., the Monkey game and the Lion game) and a paper-and-pencil version of Raven's Standard Progressive Matrices. Reading comprehension and math achievement test scores were obtained from the schools. First, the internal consistency of the Monkey game was examined. Second, multilevel modeling was used to examine the effects of classroom membership. Multilevel multivariate regression analysis was used to examine the Monkey game's concurrent relationship with the Lion game and its predictive relationships with reading comprehension and math achievement. Also, age-related differences in performance were examined. In Study 2, the concurrent relationships between the Monkey game and two tester-led computerized working memory tasks were further examined (n = 140). Also, the 1- and 2-year stability of the Monkey game was investigated. The Monkey game showed excellent internal consistency, good concurrent relationships with the other working memory measures, and significant age differences in performance. Performance on the Monkey game was also predictive of subsequent reading comprehension and mathematics performance, even after controlling for individual differences in intelligence. Performance on the Monkey game was influenced by classroom membership. The Monkey game is a reliable and suitable instrument for the online computerized and self-reliant assessment of verbal working memory in primary school children.

Relations between key executive functions and aggression in childhood

The present study examined relationships between three key executive functions (working memory, inhibition, and mental set-shifting) and multiple types of aggression in a general population sample of 9-year-old children. One hundred and forty-eight children completed a battery of executive function tasks and were rated on aggression by their primary teachers. All executive function (EF) composites were related to a composite measure of aggression. Working memory (WM) was most consistently related to the different types of aggression (overt, relational, reactive, and proactive), whereas inhibition and mental set-shifting only were related to relational and reactive aggression, respectively. Specificity in relations (studied as independent contributions) was generally low with the exception of the relation between WM and relational aggression. Taken together, our results highlight the roles of WM and relational aggression in EF-aggression relations in middle childhood.

Who's Who? Memory updating and character reference in children's narratives

PURPOSE

The capacity to update and monitor the contents of working memory is an executive function presumed to play a critical role in language processing. The current study used an individual differences approach to consider the relationship between memory updating and accurate reference to story characters in the narratives of typically developing children.

METHOD

English-speaking children from kindergarten to grade 2 ( N = 63; M age = 7.0 years) completed updating tasks, short-term memory tasks, and narrative productions. The authors used multiple regression to test whether updating accounted for independent variability in referential adequacy.

RESULTS

The capacity to update working memory was related to adequate character reference beyond the effects of age and of short-term memory capacity, with the strongest relationship emerging for maintaining reference over multiple utterances.

CONCLUSIONS

This individual differences study is the first to show a link between updating and performance in a discourse production task for young school-age children. The findings contribute to the growing body of research investigating the role of working memory in shaping language production. This study invites extension to children of different ages and language abilities as well as to other language production tasks.

Exploring the dimensionality of digit span

The Digit Span subtest from the Wechsler Scales is used to measure Freedom from Distractibility or Working Memory. Some published research suggests that Digit Span forward should be interpreted differently from Digit Span backward. The present study explored the dimensionality of the Wechsler Memory Scale-III Digit Span (forward and backward) items in a sample of heterogeneous neuroscience patients (n = 267) using confirmatory factor analysis (CFA) for dichotomous items. Results suggested that four correlated factors underlie Digit Span, reflecting easy and hard items in both forward and backward presentation orders. The model for Digit Span was then cross-validated in a seizure disorders sample (n = 223) by replication of the CFA and by examination of measurement invariance. Measurement invariance tests of the precise numerical generalization of trait estimation across groups. Results supported measurement invariance and it was concluded that forward and backward digit span scores should be interpreted as measures of the same cognitive ability.

Cognitive functioning and family risk factors in relation to symptom behaviors of ADHD and ODD in adolescents

OBJECTIVE

In this study, the authors investigated whether ADHD and oppositional defiant disorder (ODD) behaviors share associations with problems in cognitive functioning and/or family risk factors in adolescence. This was done by examining independent as well as specific associations of cognitive functioning and family risk factors with ADHD and ODD behaviors.

METHOD

A sample of 120 adolescents from the general population was assessed on various cognitive tasks. ADHD and ODD behaviors were measured through parental and teacher ratings based on Diagnostic and Statistical Manual of Mental Disorders (4th edition) criteria. Parents and adolescents provided information regarding measures of family risk factors.

RESULTS

The results show that only cognitive functioning was associated with ADHD behaviors, and family risk factors were, independent of cognitive functioning, associated with ODD behaviors.

CONCLUSION

These results suggest that cognitive performance bears a specific significance for ADHD behaviors, whereas family risk factors have specific importance for ODD behaviors.

Relationships Between Working Memory and Academic Skills: Are There Differences Between Children With Intellectual Disabilities and Typically Developing Children?

In typically developing children, working memory is linked to academic skills. However, little is known about the role working memory plays for learning in children with intellectual disabilities (ID). Therefore, the aims of this study were to examine whether different working memory functions are related to reading, spelling, and calculating in children with ID of nonspecific etiology and whether these relationships are different from the ones found in typically developing children. Forty-seven children with mild-to-borderline ID and 47 children matched for mental age were tested. Although in typically developing children, only phonological short-term memory tasks were predictive for literacy, for children with ID, visuospatial working memory tasks also accounted for variance. In typically developing children, calculation skills were predicted by phonological working memory tasks, whereas visuospatial working memory resources were crucial for children with ID. Several possible explanations are discussed for discrepancies in prediction patterns.

Working memory and response inhibition in children and adolescents: age and organization issues

The aim of the present study was to examine the role of age in the organization of verbal working memory, visuospatial working memory and inhibition; specifically whether these constructs could be considered unitary or separate in children aged 7 to 12 years (n = 164) and in adolescents aged 13 to 16 years (n = 75) using a multi-group confirmatory factor analysis. Results suggested that verbal working memory, visuospatial working memory and inhibition improved from childhood to adolescence. However, improvement was not followed by a change in the organization of these components. Verbal working memory, visuospatial working memory and inhibition constituted separable but associated constructs in children and in adolescents.

Using confirmatory factor analysis to understand executive control in preschool children: sources of variation in emergent mathematic achievement

Latent variable modeling methods have demonstrated utility for understanding the structure of executive control (EC) across development. These methods are utilized to better characterize the relation between EC and mathematics achievement in the preschool period, and to understand contributing sources of individual variation. Using the sample and battery of laboratory tasks described in Wiebe, Espy and Charak (2008), latent EC was related strongly to emergent mathematics achievement in preschool, and was robust after controlling for crystallized intellectual skills. The relation between crystallized skills and emergent mathematics differed between girls and boys, although the predictive association between EC and mathematics did not. Two dimensions of the child 's social environment contributed to mathematics achievement: social network support through its relation to EC and environmental stressors through its relation with crystallized skills. These findings underscore the need to examine the dimensions, mechanisms, and individual pathways that influence the development of early competence in basic cognitive processes that underpin early academic achievement.

Relationship between the number of life events and memory capacity in children

Stressful life events can result into declined memory performance at later age. One hypothesis suggests that stress affects the hippocampus, a brain area important for memory functioning. This study explored a potential relationship between the number of negative stressful life events and hippocampus-dependent declarative but not hippocampus-independent procedural memory performance in a community sample of 255 children, aged 6-12 years. The findings revealed that negative stressful life events were negatively related to verbal declarative memory, but not to nonverbal declarative and procedural memory. The memory impairments could not be accounted for by attention and sleep disturbances, and parenting characteristics as perceived by the child did not influence the vulnerability for the stress-related memory impairments. These findings provide further insight into the deleterious effects of negative stressful life events on learning in school-aged children.

Intelligence and Specific Cognitive Abilities in Children

This community-based study investigated the relationships between measures of specific cognitive functions (such as working memory [WM] and interference control) and intelligence in 283 8- to 11-year-old children, including 124 children who fulfilled criteria for a psychiatric diagnosis. A hierarchical regression analysis was used to overcome issues of overlapping predictor constructs. The results generally showed that measures of processing speed, WM, as well as inhibitory interference control entered in the order of presentation, each contributed uniquely to the explanation of fluid intelligence performance. The results for crystallized intelligence performance generally showed that the measures of processing speed, short-term memory (STM), WM, and sustained attention – entered in that order – made significant independent contributions. While effect sizes varied somewhat for contributions in the whole sample compared with the subgroup not meeting criteria for a psychiatric diagnosis, there were no significant differences. The findings therefore should be broadly representative in indicating that the unique aspects of these cognitive functions are important in the explanation of intelligence. The findings also demonstrate important independent features of the functions used as predictors.