The role of working memory and fluency practice on the reading comprehension of students who are dysfluent readers

Longitudinal associations between sleep duration and cognitive impairment in Chinese elderly

BACKGROUND

Age-associated cognitive decline has become a major threat to both personal welfare and public health and can further develop into Dementia/Alzheimer's disease. Sleep is significantly correlated with cognitive function, but both cognitive impairment and sleep problems increase with normal aging. This study explored how sleep duration affects cognitive performance among older adults in China.

METHODS

Using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) in 2014 and 2018, cognitive function was assessed via the Mini-Mental State Examination (MMSE), which included five domains: orientation, registration, attention or calculation, recall, and language. Logistic regression was used to examine whether the change in sleep duration was a risk factor for cognitive impairment. We also used multinomial logistic regression to study the impact of sleep duration and the changes in sleep duration on cognitive changes during the follow-up period.

RESULTS

The empirical study showed a U-shaped relationship between sleep duration and increased risk of cognitive impairment. Short (< 6 hours) and long (> 8 hours) sleep durations were positively associated with cognitive impairment. Tests of interactions between sleep duration and sleep quality showed that short sleep durations with fair sleep quality had an increased risk of cognitive impairment. Further, the participants were divided into three groups: normal cognition (MMSE > 24), mild cognitive impairment (MCI, 18 ≤ MMSE score ≤ 24), and severe cognitive impairment (MMSE < 18). First, of the participants with normal cognition at baseline, those who sleeping > 7 h at follow-up and > 7 h at both baseline and 4-year follow-up assessments could increase the risk of cognitive impairment. Second, for individuals with MCI at baseline, those who transitioned to sleeping > 7 h at follow-up period and > 7 h at both baseline and 4-year follow-up assessments had a lower chance of reverting to normal cognition.

CONCLUSION

Excessive sleep may be a major risk for cognitive impairment among older adults. Furthermore, a moderate amount of sleep could be a possible strategy to prevent cognitive impairment.

Effects of Reading Interventions Implemented for Upper Elementary Struggling Readers: A Look at Recent Research

In this study, we conducted a review of reading intervention research (1988-2019) for upper elementary struggling readers and examined intervention area (e.g., foundational, comprehension, or multicomponent) and intensity (e.g., hours of intervention, group size, and individualization) as possible moderators of effects. We located 33 studies containing 49 treatment-comparison contrasts, found small effects for foundational reading skills (g = 0.22) and comprehension (g = 0.21), and decreased effects when considering standardized measures only. For intervention area, only multicomponent interventions predicted significant effects for both comprehension and foundational outcomes. For intensity, we did not find systematic evidence that longer or individualized interventions were associated with larger effects. However, interventions implemented in very small groups predicted larger comprehension outcomes. Overall, more research examining the quality of school provided reading instruction and how the severity of reading difficulties may impact effects of more intensive interventions is needed.

Targeted school-based interventions for improving reading and mathematics for students with or at risk of academic difficulties in Grades K-6: A systematic review

Background

Low levels of numeracy and literacy skills are associated with a range of negative outcomes later in life, such as reduced earnings and health. Obtaining information about effective interventions for children with or at risk of academic difficulties is therefore important.

Objectives

The main objective was to assess the effectiveness of interventions targeting students with or at risk of academic difficulties in kindergarten to Grade 6.

Search Methods

We searched electronic databases from 1980 to July 2018. We searched multiple international electronic databases (in total 15), seven national repositories, and performed a search of the grey literature using governmental sites, academic clearinghouses and repositories for reports and working papers, and trial registries (10 sources). We hand searched recent volumes of six journals and contacted international experts. Lastly, we used included studies and 23 previously published reviews for citation tracking.

Selection Criteria

Studies had to meet the following criteria to be included: Population: The population eligible for the review included students attending regular schools in kindergarten to Grade 6, who were having academic difficulties, or were at risk of such difficulties. Intervention: We included interventions that sought to improve academic skills, were conducted in schools during the regular school year, and were targeted (selected or indicated). Comparison: Included studies used an intervention-control group design or a comparison group design. We included randomised controlled trials (RCT); quasi-randomised controlled trials (QRCT); and quasi-experimental studies (QES). Outcomes: Included studies used standardised tests in reading or mathematics. Setting: Studies carried out in regular schools in an OECD country were included.

Data Collection and Analysis

Descriptive and numerical characteristics of included studies were coded by members of the review team. A review author independently checked coding. We used an extended version of the Cochrane Risk of Bias tool to assess risk of bias. We used random-effects meta-analysis and robust-variance estimation procedures to synthesise effect sizes. We conducted separate meta-analyses for tests performed within three months of the end of interventions (short-term effects) and longer follow-up periods. For short-term effects, we performed subgroup and moderator analyses focused on instructional methods and content domains. We assessed sensitivity of the results to effect size measurement, outliers, clustered assignment of treatment, risk of bias, missing moderator information, control group progression, and publication bias.

Results

We found in total 24,414 potentially relevant records, screened 4247 of them in full text, and included 607 studies that met the inclusion criteria. We included 205 studies of a wide range of intervention types in at least one meta-analysis (202 intervention-control studies and 3 comparison designs). The reasons for excluding studies from the analysis were that they had too high risk of bias (257), compared two alternative interventions (104 studies), lacked necessary information (24 studies), or used overlapping samples (17 studies). The total number of student observations in the analysed studies was 226,745. There were 93% RCTs among the 327 interventions we included in the meta-analysis of intervention-control contrasts and 86% were from the United States. The target group consisted of, on average, 45% girls, 65% minority students, and 69% low-income students. The mean Grade was 2.4. Most studies included in the meta-analysis had a moderate to high risk of bias.The overall average effect sizes (ES) for short-term and follow-up outcomes were positive and statistically significant (ES = 0.30, 95% confidence interval [CI] = [0.25, 0.34] and ES = 0.27, 95% CI = [0.17, 0.36]), respectively). The effect sizes correspond to around one third to one half of the achievement gap between fourth Grade students with high and low socioeconomic status in the United States and to a 58% chance that a randomly selected score of an intervention group student is greater than the score of a randomly selected control group student.All measures indicated substantial heterogeneity across short-term effect sizes. Follow-up outcomes pertain almost exclusively to studies examining small-group instruction by adults and effects on reading measures. The follow-up effect sizes were considerably less heterogeneous than the short-term effect sizes, although there was still statistically significant heterogeneity.Two instructional methods, peer-assisted instruction and small-group instruction by adults, had large and statistically significant average effect sizes that were robust across specifications in the subgroup analysis of short-term effects (ES around 0.35-0.45). In meta-regressions that adjusted for methods, content domains, and other study characteristics, they had significantly larger effect sizes than computer-assisted instruction, coaching of personnel, incentives, and progress monitoring. Peer-assisted instruction also had significantly larger effect sizes than medium-group instruction. Besides peer-assisted instruction and small-group instruction, no other methods were consistently significant across the analyses that tried to isolate the association between a specific method and effect sizes. However, most analyses showed statistically significant heterogeneity also within categories of instructional methods.We found little evidence that effect sizes were larger in some content domains than others. Fractions had significantly higher associations with effect sizes than all other math domains, but there were only six studies of interventions targeting fractions. We found no evidence of adverse effects in the sense that no method or domain had robustly negative associations with effect sizes.The meta-regressions revealed few other significant moderators. Interventions in higher Grades tend to have somewhat lower effect sizes, whereas there were no significant differences between QES and RCTs, general tests and tests of subdomains, and math tests and reading tests.

Authors’ Conclusions

Our results indicate that interventions targeting students with or at risk of academic difficulties from kindergarten to Grade 6 have on average positive and statistically significant short-term and follow-up effects on standardised tests in reading and mathematics. Peer-assisted instruction and small-group instruction are likely to be effective components of such interventions.We believe the relatively large effect sizes together with the substantial unexplained heterogeneity imply that schools can reduce the achievement gap between students with or at risk of academic difficulties and not-at-risk students by implementing targeted interventions, and that more research into the design of effective interventions is needed.

Readers Recruit Executive Functions to Self-Correct Miscues During Oral Reading Fluency

Reading fluency undoubtedly underlies reading competence; yet, the role of executive functions (EF) is less well understood. Here, we investigated the relationship between children's reading fluency and EF. Children's (n = 82) reading and language performance was determined by standardized assessments and EF by parental questionnaire. Results revealed that production of more miscues was explained by poorer reading and language performance and EF. Yet, self-correcting a miscue was predicted by better EF, beyond reading and language abilities. Intriguingly, EF partially mediated the relationship between reading and self-correction, suggesting that self-correction reflects parallel recruitment and coordination of domain-specific and domain-general processes.

Executive function in the classroom: Cognitive flexibility supports reading fluency for typical readers and teacher-identified low-achieving readers

BACKGROUND

Dominant explanations of reading fluency indicate automatic phonological decoding frees mental resources for processing meaning. However, decoding automaticity does not guarantee attention to meaning. Recent neurocognitive work suggests executive functioning (EF) may contribute to fluency beyond decoding automaticity.

AIMS

Two studies examined contributions of an understudied EF, cognitive flexibility, to fluent reading and tested a teacher-administered EF intervention to improve fluency in teacher-identified low-achieving (LA) readers.

METHODS AND PROCEDURES

Study 1 assessed word reading fluency, automatic decoding, reading comprehension, verbal and nonverbal ability, and reading-specific and domain-general cognitive flexibility in 50 1st and 2nd grade typically-developing (TD) readers. Study 2 compared TD and LA readers' cognitive flexibility and examined effectiveness of cognitive flexibility intervention for improving fluency in 33 LA 2nd and 3rd graders.

OUTCOMES AND RESULTS

Reading-specific flexibility contributed to fluency beyond automatic decoding and all other control variables in TD readers who had significantly higher cognitive flexibility than LA readers. Teacher-administered EF intervention improved reading fluency for LA readers.

CONCLUSIONS AND IMPLICATIONS

These findings expand understanding of the neurocognitive basis of reading fluency and add to the growing body of evidence that EF underlies learning differences and serves as a useful target of intervention for LA students.

Reading Habits Among Older Adults in Relation to Level and 15-Year Changes in Verbal Fluency and Episodic Recall

The main objective of this study was to investigate reading habits in older adults in relation to level and 15-year changes in verbal fluency and episodic recall. We examined a sample of 1157 participants (≥55 years at baseline) up to 15 years after the baseline assessment using latent growth curve modeling of cognitive measures with baseline reading frequency (books, weekly magazines) as a predictor of cognitive level (intercept) and rate of change (slope). Subgroup analyses were performed to investigate the role of an early adult g factor in the association between reading habits and cognitive ability in midlife. Frequent reading of books, but not of magazines, was associated with higher levels of verbal fluency and recall but unrelated to rate of longitudinal decline. Subgroup analyses indicated that the g factor in early adulthood predicted reading and cognitive level in midlife and this factor removed the current association between reading habits and level of cognitive ability (both cognitive factors). The results indicate an enduring relationship between book reading and level of cognitive ability across the adult life span and provide little support of the hypothesis that frequent reading protects against late-life cognitive decline. The extent to which book reading promotes cognitive functioning in childhood/youth remains to be demonstrated. Intervention studies may be useful in this regard.

Using Meta-analytic Structural Equation Modeling to Study Developmental Change in Relations Between Language and Literacy

The purpose of this review was to introduce readers of Child Development to the meta-analytic structural equation modeling (MASEM) technique. Provided are a background to the MASEM approach, a discussion of its utility in the study of child development, and an application of this technique in the study of reading comprehension (RC) development. MASEM uses a two-stage approach: first, it provides a composite correlation matrix across included variables, and second, it fits hypothesized a priori models. The provided MASEM application used a large sample (N = 1,205,581) of students (ages 3.5-46.225) from 155 studies to investigate the factor structure and relations among components of RC. The practical implications of using this technique to study development are discussed.

Longitudinal stability of pre-reading skill profiles of kindergarten children: implications for early screening and theories of reading

Research suggests that early identification of developmental dyslexia is important for mitigating the negative effects of dyslexia, including reduced educational attainment and increased socioemotional difficulties. The strongest pre-literacy predictors of dyslexia are rapid automatized naming (RAN), phonological awareness (PA), letter knowledge, and verbal short-term memory. The relationship among these constructs has been debated, and several theories have emerged to explain the unique role of each in reading ability/disability. Furthermore, the stability of identification of risk based on these measures varies widely across studies, due in part to the different cut-offs employed to designate risk. We applied a latent profile analysis technique with a diverse sample of 1215 kindergarten and pre-kindergarten students from 20 schools, to investigate whether PA, RAN, letter knowledge, and verbal short-term memory measures differentiated between homogenous profiles of performance on these measures. Six profiles of performance emerged from the data: average performers, below average performers, high performers, PA risk, RAN risk, and double-deficit risk (both PA and RAN). A latent class regression model was employed to investigate the longitudinal stability of these groups in a representative subset of children (n = 95) nearly two years later, at the end of 1st grade. Profile membership in the spring semester of pre-kindergarten or fall semester of kindergarten was significantly predictive of later reading performance, with the specific patterns of performance on the different constructs remaining stable across the years. There was a higher frequency of PA and RAN deficits in children from lower socioeconomic status (SES) backgrounds. There was no evidence for the IQ-achievement discrepancy criterion traditionally used to diagnose dyslexia. Our results support the feasibility of early identification of dyslexia risk and point to the heterogeneity of risk profiles. These findings carry important implications for improving outcomes for children with dyslexia, based on more targeted interventions.

Reading Fluency and Students With Reading Disabilities: How Fast Is Fast Enough to Promote Reading Comprehension?

The goal of improving reading rate and fluency is to positively impact reading comprehension; however, it is unclear how fast students with learning disabilities (LD) need to read to reap this benefit. The purpose of this research was to identify the point of diminishing return for students who were dysfluent readers. Participants included 337 students with reading difficulties in second and fourth grade (61% eligible for special education; 80% with a diagnosis of LD in the area of reading) and 150 typical readers from the same general education classes. LOESS (LOcal regrESSion) plots (logistic regression) were used to determine where linear relations between reading rate and comprehension broke down for these students: the rate at which getting faster no longer contributed clearly to reading comprehension improvement. Although typical readers in this sample showed patterns of oral reading rate and comprehension similar to students in other studies, patterns for students with reading difficulties differed. For dysfluent readers, improving reading rate improved comprehension only in the bands between 35 and 75 words correct per minute in second grade and between 40 and 90 words correct in fourth grade. Reading at faster rates revealed no clear advantage for reading comprehension.

Reciprocal Effects of Self-Regulation, Semantic Knowledge, and Reading Comprehension in Early Elementary School

Many assume that cognitive and linguistic processes, such as semantic knowledge (SK) and self-regulation (SR), subserve learned skills like reading. However, complex models of interacting and bootstrapping effects of SK, SR, instruction, and reading hypothesize reciprocal effects. Testing this "lattice" model with children (n = 852) followed from first to second grade (5.9-10.4 years of age) revealed reciprocal effects for reading and SR, and reading and SK, but not SR and SK. More effective literacy instruction reduced reading stability over time. Findings elucidate the synergistic and reciprocal effects of learning to read on other important linguistic, self-regulatory, and cognitive processes; the value of using complex models of development to inform intervention design; and how learned skills may influence development during middle childhood.

Linguistic and Cognitive Profiles of 8- to 15-Year-Old Children With Specific Reading Comprehension Difficulties

This article presents two studies investigating the role of executive functioning in written text comprehension in children and adolescents. In a first study, the involvement of executive functions in reading comprehension performance was examined in normally developing children in fifth grade. Two aspects of text comprehension were differentiated: literal and inferential processes. The results demonstrated that while three aspects of executive functioning (working memory, planning, and inhibition processes) were significantly predictive of the performance on the inferential questions of the comprehension test, these factors did not predict the scores on the literal tasks of the test. In a second experiment, the linguistic and cognitive profiles of children in third/fifth and seventh/ninth grades with a specific reading comprehension deficit were examined. This analysis revealed that the deficits experienced by the less skilled comprehenders in both the linguistic and the executive domains could evolve over time. As a result, linguistic factors do not make it possible to distinguish between good and poor comprehenders among the group of older children, whereas the difficulties relating to executive processing remain stable over development. These findings are discussed in the context of the need to take account of the executive difficulties that characterize less skilled comprehenders of any age, especially for remediation purposes.

Applying a Multiple Group Causal Indicator Modeling Framework to the Reading Comprehension Skills of Third, Seventh, and Tenth Grade Students

This study demonstrates the utility of applying a causal indicator modeling framework to investigate important predictors of reading comprehension in third, seventh, and tenth grade students. The results indicated that a 4-factor multiple indicator multiple indicator cause (MIMIC) model of reading comprehension provided adequate fit at each grade level. This model included latent predictor constructs of decoding, verbal reasoning, nonverbal reasoning, and working memory and accounted for a large portion of the reading comprehension variance (73% to 87%) across grade levels. Verbal reasoning contributed the most unique variance to reading comprehension at all grade levels. In addition, we fit a multiple group 4-factor MIMIC model to investigate the relative stability (or variability) of the predictor contributions to reading comprehension across development (i.e., grade levels). The results revealed that the contributions of verbal reasoning, nonverbal reasoning, and working memory to reading comprehension were stable across the three grade levels. Decoding was the only predictor that could not be constrained to be equal across grade levels. The contribution of decoding skills to reading comprehension was higher in third grade and then remained relatively stable between seventh and tenth grade. These findings illustrate the feasibility of using MIMIC models to explain individual differences in reading comprehension across the development of reading skills.

Shared cognitive impairments and aetiology in ADHD symptoms and reading difficulties

Background

Twin studies indicate that the frequent co-occurrence of attention deficit hyperactivity disorder (ADHD) symptoms and reading difficulties (RD) is largely due to shared genetic influences. Both disorders are associated with multiple cognitive impairments, but it remains unclear which cognitive impairments share the aetiological pathway, underlying the co-occurrence of the symptoms. We address this question using a sample of twins aged 7–10 and a range of cognitive measures previously associated with ADHD symptoms or RD.

Methods

We performed multivariate structural equation modelling analyses on parent and teacher ratings on the ADHD symptom domains of inattention and hyperactivity, parent ratings on RD, and cognitive data on response inhibition (commission errors, CE), reaction time variability (RTV), verbal short-term memory (STM), working memory (WM) and choice impulsivity, from a population sample of 1312 twins aged 7–10 years.

Results

Three cognitive processes showed significant phenotypic and genetic associations with both inattention symptoms and RD: RTV, verbal WM and STM. While STM captured only 11% of the shared genetic risk between inattention and RD, the estimates increased somewhat for WM (21%) and RTV (28%); yet most of the genetic sharing between inattention and RD remained unaccounted for in each case.

Conclusion

While response inhibition and choice impulsivity did not emerge as important cognitive processes underlying the co-occurrence between ADHD symptoms and RD, RTV and verbal memory processes separately showed significant phenotypic and genetic associations with both inattention symptoms and RD. Future studies employing longitudinal designs will be required to investigate the developmental pathways and direction of causality further.

Verbal and visuospatial working memory as predictors of children's reading ability

Children with reading difficulties often demonstrate weaknesses in working memory (WM). This research study explored the relation between two WM systems (verbal and visuospatial WM) and reading ability in a sample of school-aged children with a wide range of reading skills. Children (N = 157), ages 9-12, were administered measures of short-term memory, verbal WM, visuospatial WM, and reading measures (e.g., reading fluency and comprehension). Although results indicated that verbal WM was a stronger predictor in reading fluency and comprehension, visuospatial WM also significantly predicted reading skills, but provided more unique variance in reading comprehension than reading fluency. These findings suggest that visuospatial WM may play a significant role in higher level reading processes, particularly in reading comprehension, than previously thought.

A Dominance Analysis Approach to Determining Predictor Importance in Third, Seventh, and Tenth Grade Reading Comprehension Skills

The purpose of the present study was to investigate and rank order by importance the contributions of various cognitive predictors to reading comprehension in third, seventh, and tenth graders. An exploratory factor analysis revealed that for third grade, the best fit was a four-factor solution including Fluency, Verbal Reasoning, Nonverbal Reasoning, and Working Memory factors. For seventh and tenth grade, three-factor solutions with Fluency, Reasoning, and Working Memory factors were the best fit. The three and four-factor models were used in separate dominance analyses for each grade to rank order the factors by predictive importance to reading comprehension. Results indicated that Fluency and Verbal Reasoning were the most important predictors of third grade reading comprehension. For seventh grade, Fluency and Reasoning were the most important predictors. By tenth grade, Reasoning was the most important predictor of reading comprehension. Working Memory was the least predictive of reading comprehension across all grade levels. These results suggest that inferential reasoning skills become an important contributor to reading comprehension at increasing grade levels.

Why does working memory capacity predict variation in reading comprehension? On the influence of mind wandering and executive attention

Some people are better readers than others, and this variation in comprehension ability is predicted by measures of working memory capacity (WMC). The primary goal of this study was to investigate the mediating role of mind-wandering experiences in the association between WMC and normal individual differences in reading comprehension, as predicted by the executive-attention theory of WMC (e.g., Engle & Kane, 2004). We used a latent-variable, structural-equation-model approach, testing skilled adult readers on 3 WMC span tasks, 7 varied reading-comprehension tasks, and 3 attention-control tasks. Mind wandering was assessed using experimenter-scheduled thought probes during 4 different tasks (2 reading, 2 attention-control). The results support the executive-attention theory of WMC. Mind wandering across the 4 tasks loaded onto a single latent factor, reflecting a stable individual difference. Most important, mind wandering was a significant mediator in the relationship between WMC and reading comprehension, suggesting that the WMC-comprehension correlation is driven, in part, by attention control over intruding thoughts. We discuss implications for theories of WMC, attention control, and reading comprehension.