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Background: During digital reading on internet-connected devices, students may be exposed to a variety of on-screen distractions. Learning by reading can therefore become a fragmented experience with potentially negative consequences for reading processes and outcomes. Objectives: This study investigated the effects of on-screen distractions, as advertisements and social media notifications, during reading on text processing, perception of cognitive load and text comprehension. Methods: University students (N = 54) participated in a within-participant design. They read two digital science expository texts, one with and the other without distractions. Participants' eye movements were recorded during reading. Process variables were the first-pass fixation time on text areas and the fixation time on distractions. Working memory was taken into account as possible moderator of outcome variables, while controlling for prior knowledge and text topic. Results: Participants spent very short time fixating the distractions. From linear mixed models the main effect of distractions did not emerge for the immediate text processing. Perception of cognitive load and text comprehension were not affected by distractions either. Among individual differences, prior knowledge contributed to text comprehension. Text topic contributed to the perception of cognitive load. Takeaways: The study suggests that simple, static and very usual on-screen distractions during reading do not seem particularly harmful for university students' processing and comprehension of expository texts. Findings indicate the importance of students' top-down attentional control over on-screen distractions not to impair their own comprehension of complex content.

Background: Previous research has demonstrated that quizzing can improve self-regulation processes and learning performances. However, it remains unclear whether quizzes in multimedia material bring similar benefits, and whether interindividual differences such as working memory capacity (WMC) modulate quizzing effects. Aims: This study aimed to examine the effects of embedded quizzes (multiple quizzes within the learning sequence) with feedback during a multimedia learning sequence on self-regulated processing (monitoring and control) and learning performances on repeated (material already tested) and new (untested) questions, and possible WMC moderation on performances. Sample and Methods: Participants were 59 students who learned a multimedia neuroscience course module in either a no-quiz or embedded quizzes condition. With regard to self-regulated processing, control was assessed with eye-tracking measures (fixation durations and transitions between texts and illustrations), and monitoring by comparing self-reported judgements of learning with actual performances (calibration). At the end, students' WMC was measured, and learning performances were assessed with repeated and new questions. Results: Quizzing improved learning performances on repeated and new questions, and enhanced monitoring (better calibration). Students with low WMC benefited more from quizzing for new questions than those with high WMC. However, contrary to our hypothesis, the embedded quizzes group allocated less time to the learning than the no-quiz group. Conclusions: Embedded quizzes are relevant tools to help students recalibrate their monitoring process and foster more effective self-regulated learning. Results confirm that the use of quizzes can be recommended to improve the learning of multimedia material, especially among students with low WMC.

Phonological awareness and phonological working memory are essential for successful language acquisition and development of literacy. Although this essence is language-universal, its degree varies for different languages, depending, in part, on language transparency. The current study analyzes the adapted versions of the pseudoword repetition test (assessing phonological working memory) and Rosner's Auditory Segmentation test (assessing phonological awareness) in a typically developing Russian native sample of children (n = 502). As a preparatory step to item analysis, we investigated the effects of grade and gender on performance using a mixed effects model. The initial item analysis was carried out using model comparison within the Item Response Theory model framework and threshold/slope analysis. The majority of the items in both assessments did not differentiate between students with different levels of phonological ability. Further item selection using regression tree models led to the formation of predictive and non-predictive item subsets for each assessment. After comparing the item subsets on various linguistic metrics, the differences were found in number of syllables and subsyllabic complexity for the pseudoword repetition test and elision segment position for the auditory segmentation test. The findings inform test development strategies in the cases of extremely low difficulty/discrimination of the items and outline a blueprint of pseudoword repetition and auditory segmentation test's adaptation for potentially detecting higher levels of phonological ability in transparent languages such as Russian.

We examined the relations of language skills (vocabulary, listening comprehension, and oral retell), transcription skills (spelling and handwriting fluency), and domain-general cognitions/executive functions (working memory and attentional control) to writing quality for English-Spanish emergent bilingual children in Grade 1. Data were from a convenience sample of 211 children (57% girls; 82% Hispanic, 9.5% White, 4% Asian American children) who were assessed on written composition, vocabulary, listening comprehension, oral retell, and spelling in English and Spanish; handwriting fluency and working memory in English; and attentional control rated by their teachers. Confirmatory factor analysis results showed that writing quality in English and Spanish in narrative and opinion genres was best described as a unidimensional skill. Structural equation model results showed that English oral language, English spelling, and Spanish spelling skills, but not Spanish oral language skill, were independently related to writing quality, after controlling for gender, English learner status, Hispanic status, and enrollment in dual immersion program. The relations of working memory and attentional control to writing quality were indirect, mediated by oral language and transcription skills. These results are discussed in light of theory and in the context of emergent bilingual children in primary grades.

The main objective of this methodological article is to discuss the contribution of response times as a tool in education research. The use of response times in research is largely a legacy of the work carried out in cognitive psychology, which has made it possible to describe the cognitive processes involved in information processing. In education, research that incorporates response times into its methodological design often has two main objectives: 1) evaluate the automation of basic learning and 2) infer the cognitive processes involved in academic learning, such as working memory and inhibitory control. This article addresses and discusses specific research designs that use response times across various academic disciplines and instructional levels, offering a comprehensive overview of the potential applications of response times in education research. In light of this overview, utilizing response times in education research not only emerges as relevant but also serves to complement existing methodological tools. For instance, such designs can aid in identifying the relative difficulty of different types of learning, understanding the underlying reasons for such variations, and offering valuable insights for developing learning sequences and pedagogical interventions that are more consistent with learning processes.

The rising use of technology in classrooms has also brought with it a concomitant wave of computer-based assessments. The argument for computer-based testing is often framed in terms of efficiency and data management: computer-based tests facilitate more efficient processing of test data and the rate at which feedback can be leveraged for student learning rather than being framed in terms of the direct effects that students experience from engaging with novel learning tools. Whilst potentially beneficial, for some students the outcomes of computer-based tests may be counter-productive. This review considers the cognitive, and often implicit, consequences of testing mode upon students with reference to testing performance and subjective measures of cognitive load. Considerations for teachers, test writers and future research are presented with a view to raising the significance of learners' subjective experiences as a guiding perspective in educational policy making.

Foreign language anxiety has influenced reading achievement in English as a second language learning (ESL). However, less is known about how foreign language anxiety affects Chinese students learning English as L2 and the interplay between foreign language anxiety and cognitive-linguistic factors on L2 reading performance. This longitudinal study examined the impact of foreign language anxiety on English word reading and the mediating effect of cognitive-linguistic skills between foreign language anxiety and English word reading in a sample of 177 grades 2 to 3 ESL Chinese students at risk of English learning difficulties. Foreign language anxiety was assessed using parent-rated and child-rated questionnaires at T1. Students were assessed on English word reading at T1 and T2 and cognitive-linguistic skills: phonological awareness, expressive vocabulary knowledge, and working memory at T1. Path analysis showed that parent-rated foreign language anxiety significantly predicted T1 English word reading after controlling for working memory. However, child-rated foreign language anxiety did not significantly predict English word reading. Moreover, mediation analysis showed that parent-rated foreign language anxiety significantly predicted T2 English word reading through T1 English word reading and expressive vocabulary knowledge. Findings highlight the impact of foreign language anxiety on L2 word reading and suggest that mothers' involvement in children's ESL is essential.

Previous research has variably indicated the role of working memory in error detection by which working memory played a role in rhythmic error detection but not melodic error detection. Here, we devised a longer melodic error detection task for college musicians in an auditory, rather than visual, condition using classical excerpts, which we compared to briefer visual and auditory control conditions. These tests were compared to performance on a test of verbal working memory (forward digit span test) and an experimenter-created tonal working memory test. The tonal working memory test was positively related to the forward digit span test, the melodic error detection, and the visual control but not to the auditory control. Performance on the error detection test was not significantly related to year in school, level of aural skills class, years of private piano, or level of group piano class. Our participants performed similarly on the aurally presented melodic error detection of classical excerpts and the briefer visual control but not on the briefer aural control. Among other variables, years of experience on a second instrument was a significant predictor of error detection skill. High familiarity ratings with a classical excerpt did not yield a relationship to error detection performance.

Purpose: Although the existing literature has explored the link between cognitive functioning and speech recognition in noise, the specific role of fluid intelligence still needs to be studied. Given the established association between working memory capacity (WMC) and fluid intelligence and the predictive power of WMC for speech recognition in noise, we aimed to elucidate the mediating role of fluid intelligence. Method: We used data from the n200 study, a longitudinal investigation into aging, hearing ability, and cognitive functioning. We analyzed two age-matched samples: participants with hearing aids and a group with normal hearing. WMC was assessed using the Reading Span task, and fluid intelligence was measured with Raven's Progressive Matrices. Speech recognition in noise was evaluated using Hagerman sentences presented to target 80% speech-reception thresholds in four-talker babble. Data were analyzed using mediation analysis to examine fluid intelligence as a mediator between WMC and speech recognition in noise. Results: We found a partial mediating effect of fluid intelligence on the relationship between WMC and speech recognition in noise, and that hearing status did not moderate this effect. In other words, WMC and fluid intelligence were related, and fluid intelligence partially explained the influence of WMC on speech recognition in noise. Conclusions: This study shows the importance of fluid intelligence in speech recognition in noise, regardless of hearing status. Future research should use other advanced statistical techniques and explore various speech recognition tests and background maskers to deepen our understanding of the interplay between WMC and fluid intelligence in speech recognition.

The aim of the present study was to determine the effect of the game-based training program on fundamental movement skills (FMS) and working memory (WM) in male children with Down syndrome. Twenty-one children ages 9 to 11 years were assigned to either a Game-Based Training (GBT) or No-Training (NT) group. The GBT group participated in 12 sessions of game-based training, three sessions per week and 45 minutes per session whereas the NT group just performed normal daily activities. TGMD 2-Test was used to evaluate the motor development quality. The results showed that the GBT group performed better than the NT group in locomotor and manipulative skills. In the Corsi Block Task, although the mean scores of the GBT group were better than the NT group, it was not statistically significant. Our result revealed that after the game-based training program, participant's scores improved in fundamental movement skills, but no significant improvement was observed in the working memory scores. Therefore, these findings support the positive effect of game-based training on fundamental movement skills in children with Down syndrome.

Inhibition and Working Memory (WM) are crucial predictors of everyday life autonomies in people with Down Syndrome (DS). We aimed to investigate the possible relationship between different levels of autonomy, inhibitory sub-components and WM in people with DS. Twenty-two adolescents and adults with DS were enrolled in the study and were assessed with tasks tapping on response inhibition, interference suppression and WM. With a questionnaire on levels of autonomy, educators evaluated the sample with DS. Considering levels of autonomy, we divided participants into two groups: one with lower levels of autonomy and one with medium-to-high levels of autonomy. Results showed differences between the two groups in WM tasks and both inhibitory dimensions. More specifically, interference suppression seems to have a major role in the acquisition of important, more structured aspects of autonomy such as shopping, behaviour on the road, communication and reading-writing skills. On the other hand, response inhibition seems to be linked to crucial aspects of learning, such as reading and writing and handling a telephone. The results are discussed in terms of possible implementation in training in clinical and educational settings.

The present study examines the effects of pre-task explicit instruction on second language (L2) oral self-repair behaviour while controlling for the effects of working memory. The participants were 121 Iranian learners of English at incipient levels of language proficiency. Their working memory was measured using an operation span task and then they were randomly assigned to a control and an experimental group. Both groups performed a picture story-retelling task that was preceded by five minutes of planning time. During the planning time, the experimental group also received a grammar handout that explained English relative clauses. The instances of self-repairs were identified through stimulated recall interviews that immediately followed performance on the oral task. They were then classified into categories of global form repairs (F[subscript G]-repairs), local form repairs (F[subscript L]-repairs), and content repairs (C-repairs). A series of one-way ANCOVAs were run, the results of which indicated pre-task explicit instruction had significant and beneficial effects on F[subscript L]-repairs and adverse effects on C-repairs. The covariate was only associated with repairing the target structure. The findings are discussed in light of the Extended Trade-off Hypothesis and confirm the view that pre-task explicit instruction tends to foster a focus on form at the expense of meaning.

Working memory functions as an underlying force for school readiness, yet many autistic children have difficulties with it. Similarly, autistic children tend to start kindergarten with less school readiness compared with their peers. In addition, children from lower socioeconomic status (SES) backgrounds face additional barriers in working memory and school readiness. Preschool-age children with autism in the United States are entitled to pre-kindergarten (pre-K) education, yet it is unknown whether pre-K education produces long-lasting benefits in working memory. This study used a nationally representative data set to examine whether pre-K education has immediate and long-term benefits on the working memory development of children in the general sample, and whether it is particularly beneficial for autistic children's working memory development, when controlling for SES. A series of multiple regression and interaction analyses indicated that, for the general sample, having attended pre-K predicted advanced working memory during the first 2 years of elementary school (K to first grade). Particularly for autistic children, the onset of such benefits started later, in Spring of first grade, but lasted longer, until Spring of third grade (3 years). Practical implications and future directions pertaining to capitalizing on autistic children's cognitive potential and this protracted window of growth are discussed.

This study examined the independent contribution of morphological awareness and orthographic awareness in reading comprehension, controlling for working memory and reading fluency in Arabic-speaking children. Participants (N = 244) from grades four and five, were classified into typical comprehenders (n = 207) and poor comprehenders (n = 37). All the participants underwent reading comprehension tasks (sentence comprehension and reading maze), orthographic awareness tasks (word choice and parsing), morphological awareness test (root morpheme awareness), working memory test (listening sentence span), word reading fluency, and word reading accuracy and fluency (reading in one minute). The results indicated that morphological awareness and orthographic awareness contributed significantly to reading comprehension (composite scores) only in the typical comprehenders group. Although morphological awareness showed significant predictive relation with reading comprehension, orthographic awareness was a stronger predictor of reading comprehension while controlling for working memory and reading fluency. The findings are discussed, and future directions for research are suggested.

The preschool period is recognized as a crucial phase for fostering the social development of children. Self-regulation during the developmental period contributes to management skills in social contexts and thus helps establish positive standards of behavior for peer relationships. Effective interventions can improve self-regulation skills. The main purpose of this study is to detect the predictive impact of self-regulation skills on peer relationships in preschool children. The participants consisted of 165 children of Turkish extraction (between the ages of 5 and 6). 81 of them were girls, and 84 were boys. The Self-Regulation Skills Scale for Children aged 4-6 (Teacher Form) and the sociometry technique based on peer nomination were utilized. The study results asserted that young children's self-regulation variables (inhibitory control, attention, and working memory) influenced their levels of being positively and significantly liked by peers. Moreover, young children's self-regulation variables (inhibitory control, attention, and working memory) affected their levels of being negatively and significantly disliked by peers. Also, inhibitory control, attention, and working memory significantly predicted the levels of social preference.

Mathematics learning presents significant challenges for individuals with autism spectrum disorder (ASD). This study delves into the difficulties faced by ASD students in a private school in learning mathematics, according to the perspectives of teachers and parents. A qualitative study was conducted using semi-structured interviews with three special needs teachers specializing in autism and two parents of ASD students and verified from observations of six ASD students classified as level 1 severity according to DSM-IV in their mathematics classes. The difficulties identified among ASD students include difficulty processing information and working memory, need for individualized instruction, short attention span, difficulty understanding mathematical concepts and inability to express symbols. Recommendations include integrating creative art and technology to support drill and practice, mastery learning, blended learning, individualized educational programs, and visual aids. Further research is needed to develop mobile applications for mathematics that integrate creative arts.

Flipped learning has become the focus in many educational contexts especially with the integration of technological tools in learning space for the last decade. In flipped learning, learners perform surface learning at home, whereas deep learning such as problem-solving, critical thinking exercises etc. is covered in the classroom which potentially increases motivation and satisfaction of learners. Cognitive load, the assumed load of the working memory caused by the processing of tasks, has also attracted attention in online learning settings which pose different processing demands. This study took place in the extraordinary settings of education during the COVID-19 pandemic which required online education for all education levels. A fourth-year course of an ELT program was delivered through a flipped learning approach during online education. Learners' motivation, use of learning strategies, satisfaction and cognitive load levels were calculated at the end of the intervention and their perceptions regarding the experience were investigated through an open-ended questionnaire. The results showed that their motivation and satisfaction levels were quite high as well as their strategy uses whereas cognitive load levels were comparatively low. Inferential statistics showed that relationships exist between and among the motivation, learning strategies and cognitive load at various levels. Motivation emerged to be a significant predictor of course satisfaction whereas time spent for the flipped lectures predicted course achievement. Learners' perceptions of flipped learning process were generally positive while they also articulated some drawbacks of it like instructional tools-related and individual learner-related problems.

This study aims to evaluate word callers attending the fourth grade of primary school in terms of rapid naming, verbal working memory, and attention skills, and to examine the effect of the reciprocal teaching approach on the development of word callers' reading comprehension skills. The study group consisted of 25 word callers and 21 independent readers. Fourth-grade students who are at the independent level in word recognition skills and at the level of frustration in reading comprehension skills are defined as word callers. On the other hand, students who are at the independent level in both word recognition and reading comprehension skills are defined as independent readers. According to the findings, difficulties in rapid naming, verbal working memory and attention skills are common characteristics of word callers. On the other hand, with the reciprocal teaching approach applied for 12 weeks, significant improvements were achieved in the reading comprehension skills of word callers. In this direction, it can be interpreted that the reciprocal teaching approach eliminated the difficulties experienced by word callers.

This study investigates school-age children's arithmetic operations performance while solving larger-size problems which produces interferences in memory. Complex problems can trigger competing responses in working memory, which are irrelevant to a task goal and increase the likelihood of interference from previously learned problems (De Visscher et al., 2018). Interference control in working memory is required to be able to manage and suppress irrelevant information while performing cognitive tasks such as arithmetic problem-solving (Unsworth, 2010). The present study explores potential cognitive processes while performing arithmetic tasks and emphasizes the important role of interference control for better performance in such tasks. This study applied a mixed-effect model experimental design. Forty-four primary school children were involved in the study. The results showed that children's performance in terms of correct responses was similar for both small-size and large-size problems. However, their response speed was significantly lower in larger-size problems, which created more interference in working memory.

This study examines the effects of a working memory (WM) sensitive math intervention in students with learning disabilities (LD). The intervention aims to improve early mathematical competencies while accounting for weak cognitive resources through a reduced instructional design. These principles are considered to be effective for learning. Ten students with mild to moderate intelligence impairment participated in our study. We applied an AB single-case intervention study across participants to evaluate the effects of the intervention. The students take part in at least 10 30-minute intervention sessions. Non-overlap indices, as well as regression analysis, support positive effects on students' mathematical competencies. Nevertheless, there are still students for whom the effects were unstable or failed to materialize. Besides the effectiveness of the WM-sensitive math intervention, the results support the assumption that the mathematical learning of students with LD is similar to that of students without LD but delayed.

This study strived to determine the effectiveness of integrative teaching of reading strategies and working memory on basic math and problem-solving skills. It is a quasi-experimental pretest-posttest study carried out on 50 second-graders from Chahashk Shandiz village in the academic year of 2020-2021 who were randomly selected by cluster sampling and randomly divided into experimental and control groups. The intervention was performed by cellphone software through virtual education in two steps. The experimental group underwent integrative training for 20 sessions, but the control group did not receive any intervention. Colored Progressive Matrices (1956) and a researcher-made story problem-solving and arithmetic skills test were used to collect data. Descriptive statistics (mean and standard deviation) and one-way multivariate analysis of covariance were used to analyze the data. The results showed that the integrative teaching of reading strategies and working memory enhanced the basic math skills, with an effect size of 0.67 in second-grade elementary students (P<0.001). According to the results, integrative teaching improved students' problem-solving skills but did not affect their skills in arithmetic operations. Therefore, second-grade elementary teachers can use this method to enhance their story problem-solving skills.

The authors compare pretend play and executive function both in preschool children with an acquired brain injury and in neurotypical preschool children. They find the ability to produce logical, sequenced pretend play actions and object substitutions in play correlates strongly with executive function ability in both groups, and working memory emerges in their study as the most reliable predictor of pretend play in both groups of children. Their investigation highlights the need to include pretend play in rehabilitating children with brain injuries and the importance of pretend play for developing executive function in all children.

Despite growing interest in spaced retrieval methods, a research gap has been discovered, with insufficient data to support best practises in year-one science. After analysing five systematic action cycles, four interrelated themes emerged: dual coding, cognitive load, peer communication, and feedback-driven metacognition. While literature emphasises the need to take a child's cognitive load into account, the themes of peer communication and dual coding provoked debate among participants. Despite this conflict, an agreement was reached on how limited reading abilities affect retrieval practise. While this small-scale study cannot draw definitive conclusions, I discovered that by optimising cognitive load, teachers can ensure that a task is desirably difficult using dual coding, discussion, and feedback-driven metacognition, all of which contributed to the success of knowledge acquisition methodologies. According to my research, ensuring a retrieval task is challenging, increases children's development of retention of scientific knowledge. However, minimising literacy constraints is critical to avoid thinking being exhausted by writing or reading, rather than recalling and applying. Consequently, the relevance of the study for education and society is illustrated by the findings, which emphasise the necessity to reduce extraneous load (reading and writing) during retrieval tasks and propose potential solutions to this issue.

This study explores how kindergarten students from a multilingual sample (n = 131) representing 23 different languages differ in response to intervention, based on their skill in mathematics and domain general cognitive skills. Analyses for this study indicate significant correlations between initial math skill, phonological memory, working memory, and language proficiency. There was no statistically significant relationship demonstrated between gains in mathematics and phonological memory, working memory, and language proficiency. No moderation effect was found between domain general skills and response to math intervention. Implications of this work will inform development and delivery of math interventions for multilingual students in kindergarten.

Various studies empirically proved the value of highly informative feedback for enhancing learner success. However, digital educational technology has yet to catch up as automated feedback is often provided shallowly. This paper presents a case study on implementing a pipeline that provides German-speaking university students enrolled in an introductory-level educational psychology lecture with content-specific feedback for a lecture assignment. In the assignment, students have to discuss the usefulness and educational grounding (i.e., connection to working memory, metacognition or motivation) of ten learning tips presented in a video within essays. Through our system, students received feedback on the correctness of their solutions and content areas they needed to improve. For this purpose, we implemented a natural language processing pipeline with two steps: (1) segmenting the essays and (2) predicting codes from the resulting segments used to generate feedback texts. As training data for the model in each processing step, we used 689 manually labelled essays submitted by the previous student cohort. We then evaluated approaches based on GBERT, T5, and bag-of-words baselines for scoring them. Both pipeline steps, especially the transformer-based models, demonstrated high performance. In the final step, we evaluated the feedback using a randomised controlled trial. The control group received "feedback as usual" ("essential feedback"), while the treatment group received "highly informative feedback" based on the natural language processing pipeline. We then used a six items long survey to test the perception of feedback. We conducted an ordinary least squares analysis to model these items as dependent variables, which showed that highly informative feedback had positive effects on helpfulness and reflection.

Some listeners exhibit higher sensitivity to subphonemic acoustic differences (i.e., higher speech gradiency). Here, we asked whether higher gradiency in a listener's first language (L1) facilitates foreign language learning and explored the possible sources of individual differences in L1 gradiency. To address these questions, we tested 164 native Spanish speakers with different linguistic profiles. Speech gradiency was assessed via a Visual Analogue Scale task, and foreign language proficiency was assessed via an English vocabulary test. Possible sources of gradiency included domain-general auditory acuity, overall exposure to spoken language (indexed by age), and exposure to phonological diversity. Control measures were collected to account for variables such as phoneme categorization consistency, working memory, and musical training. The results revealed a positive link between L1 speech gradiency and vocabulary acquisition in a foreign language over and above all other variables. L1 speech gradiency itself was predicted by domain-general auditory acuity and overall exposure to spoken language.

Previous research has demonstrated conflicting findings concerning orthographic access in older age. The current study examines whether older adults rely more heavily on stored knowledge while spelling, through testing of word concreteness. Forty-one younger (age 20-29), 41 middle age (age 45-55), and 40 healthy older adults (age 70-80) spelled 60 concrete and 60 abstract Hebrew words from dictation. Coding distinguished between homophonic errors that involved the use of a phonologically plausible letter and non-homophonic errors that could indicate working memory difficulties. All participants spelled more concrete than abstract words correctly, the two younger age groups spelled more words correctly than did the older adults, and there was an interaction between condition and age, with a greater concreteness effect in the oldest group. Additionally, younger adults made more homophonic errors than did older adults, whereas older adults made significantly more non-homophonic errors than the other two groups. We suggest that older adults' misspellings do not reflect impairment in activating orthographic representations, but difficulties in the execution of spelling. The study provides evidence for an aging-related decreased use of phoneme-to-grapheme conversion rules in spelling (e.g., sub-lexical route), alongside increased reliance on stored orthographic knowledge (e.g., lexical route).

Mind wandering occurs when a reader's thoughts are unrelated to the text's ideas. We examined the relation between mind wandering and readers' memory for text. More specifically, we assessed whether mind wandering inhibits the reader's development of the situation model and thus their ability to identify and recall the text's most central ideas. Undergraduate participants (M = 18.92 years; SD = 1.32) read and recalled three expository passages. Participants responded to intermittent probes to report mind wandering frequency. We examined how mind wandering impacted the readers' situation model, indicated by the proportion of central and peripheral ideas recalled. Using path analysis models, we found that mind wandering negatively predicted the recall of central, but not peripheral, ideas. The effect of mind wandering on the recall of central ideas was not explained by working memory span (measured by WAIS-IV digit span backward and letter-number sequencing), word reading skill (measured by Letter-Word Identification and Word Attack), or general reading comprehension skill (measured by the Gates-MacGinitie Reading Test). These results indicate that mind wandering hinders the recognition and recall of a text's most central ideas and suggest that mind wandering impacts the development of a coherent situation model. This effect seems to be independent of working memory, word reading, and general reading comprehension skill. Future studies should test approaches to decrease mind wandering among adult readers.

Retrieval practice is a learning strategy that has repeatedly been found to have positive effects on memory and learning. However, studies indicate that students rarely use retrieval practice on a voluntary basis. The objective of the present study was to examine students' self-regulated use of retrieval practice, and to determine whether sex and individual differences in cognitive and non-cognitive aspects are related to optional use of practice testing. A classroom study was conducted with 146 upper-secondary school students taking courses in mathematics and Swedish. An ABAB design was used to compare students' optional and non-optional use of retrieval practice (i.e., repeated online quizzing). Students performed cognitive tasks to assess working memory capacity and fluid intelligence and completed self-reports of non-cognitive factors related to school achievement, such as grit, need for cognition (NFC), conscientiousness and openness. Quiz use was then compared using paired- and independent-samples t-tests, and hierarchical linear regression analyses explored relations to individual differences. The results showed that students completed significantly fewer quizzes in the optional sections than in the non-optional sections, and that females completed significantly more optional quizzes than males in Swedish, but not in mathematics. Further, the results showed that conscientiousness predicted optional quiz use in mathematics, whereas sex, NFC, conscientiousness, and openness predicted quiz use in Swedish. To conclude, although the findings show a relatively low optional/self-regulated use of practice testing, in line with earlier research, they suggest that sex and non-cognitive factors, such as personality characteristics, can predict optional use of practice testing.

Objective: To investigate the neural mechanisms underlying working memory (WM) deficits in children with ADHD. Method: WM was compared between thirty-four children with ADHD and thirty-four matched controls using neuropsychological tests, spatial and verbal versions of modified delayed matching-to-sample (DMTS) tasks, and the event-related potential technique. Results: Children with ADHD demonstrated poor behavioral performance, delayed P3 latencies in high-load spatial modified DMTS tasks during encoding, and delayed P2 and N2 latencies during retrieval in spatial modified DMTS tasks. In high-load verbal modified DMTS tasks during encoding, they showed a smaller P3 amplitude. Discussion: Pronounced deficits in the central executive system in children with ADHD were exhibited by neuropsychological tests and the modified DMTS task. Children with ADHD exhibited a slowing of processing speed during encoding. Under high-load conditions, they showed a reduced P3 amplitude during retrieval, suggesting reduced neural resource allocation was available when the central executive of the working memory was heavily loaded.

Background and Aims: This study examined the effects of working memory training (WMT) on WM and fluid intelligence. A novel four-pronged model of mediated learning, cognitive functions, task characteristics and metacognition is presented as a conceptual basis for the Modifiability of a Working Memory Program (MWMP). Our basic assumption is that increasing WM depends on a synchronized combination of the four components. Sample: A group of typically developed preschool children (n = 62) participated in the experimental group, receiving the MWMP. They were compared with a control group (n = 56) of preschool children who engaged in a substitute program. This comparison allowed us to discern the specific effects of the MWMP. Methods: All participants received tests of WM, self-regulation and analogical reasoning before and after the intervention. The MWMP was administered to children in the experimental group for 10 weekly sessions, each lasting 40 minutes, in small groups of two children. The children in the control group engaged in didactic activities that were part of a school curriculum routine for kindergartners for the same length of time. Results: We used ANCOVA analysis to compare the Treatment x Time with age and socioeconomic status as covariates. The findings revealed a higher improvement in some WM and self-regulation tests among children in the experimental group compared to those in the control group. However, no significant transfer effects were observed in analogical thinking. Conclusion: The findings confirm the effectiveness of a non-computerized WMT among kindergartners and support our four-pronged theoretical model. We also discuss earlier findings on far-transfer effects and educational implications. We suggest that future WM studies adopt the following: (1) the development of training methods that are theoretically anchored; (2) training procedures should not rely heavily on computerized exercises but can be adapted to group characteristics, educational settings and cost-effectiveness aspects; (3) varying the task characteristics and training strategies to stimulate task-intrinsic motivation; (4) identifying training strategies to produce cognitive improvements underlying WM; (5) intervention should target individuals in early development as much as possible; (6) development of training procedures that facilitate motivation; and (7) providing empirical evidence of far-transfer effects for WM training. The empirical evidence should link gains in WM capacity and achievements in academic and other life domains.

Limited longitudinal studies have explored the development of reading, along with its predictors, in a language characterized by shallow orthography and a simple syllabic structure. In a 5-year longitudinal study, we investigated the development of reading skills in 327 Italian-speaking children (male: n = 180, 55%) from Grade 1 (mean age = 6.16 ± 0.28) to Grade 5 (mean age = 10.82 ± 0.31). We tested their reading performance at the end of each school year (Grade 1-5) and examined the impact of early cognitive factors (phonological awareness-PA, verbal short-term memory-vSTM, and non-verbal intelligence), environmental factors (socioeconomic status) as well as Grade 1 reading proficiency on subsequent reading development. A linear development of reading skills was found in both children classified as typical readers and those with reading disabilities. Non-verbal intelligence, PA, vSTM and reading proficiency at the end of Grade 1 predicted reading development throughout primary school (reading speed: R2-Intercept = 61.8%; R2-Slope = 12.9%, and reading accuracy: R2-Intercept = 40.1%; R2-Slope = 22.2%). The stability of reading performance across school grades highlights the significance of early reading skills as a marker and target for early intervention programs.

Caregiver executive functions (EFs) play an integral role in shaping cognitive development. Here, we investigated how caregiver EF abilities (86 caregivers; "mean age" = 33.4 years, SD = 4.5) was associated with visual working memory (VWM) in infants (86 infants females; mean age = 250.6 days, SD = 35.8). The BRIEF-A was used to assess caregiver EFs, and a preferential looking task along with fNIRS was used to assess VWM function in infants. Our findings revealed that better caregiver behavioral regulation was associated with better VWM performance, greater right-lateralized parietal activation, and left-lateralized frontal suppression, while better caregiver metacognition and emotional control was associated with greater right-lateralized temporal suppression in infants. Taken together, these associations suggest that better caregiver EF abilities might shape visuo-spatial attention and memory, guide fixation on task-relevant goals, and suppress distractions in children from as early as the first year of life.

Recent studies using the diffusion decision model find that performance across many cognitive control tasks can be largely attributed to a task-general efficiency of evidence accumulation (EEA) factor that reflects individuals' ability to selectively gather evidence relevant to task goals. However, estimates of EEA from an n-back "conflict recognition" paradigm in the Adolescent Brain Cognitive DevelopmentSM (ABCD) Study, a large, diverse sample of youth, appear to contradict these findings. EEA estimates from "lure" trials--which present stimuli that are familiar (i.e., presented previously) but do not meet formal criteria for being a target--show inconsistent relations with EEA estimates from other trials and display atypical v-shaped bivariate distributions, suggesting many individuals are responding based largely on stimulus familiarity rather than goal-relevant stimulus features. We present a new formal model of evidence integration in conflict recognition tasks that distinguishes individuals' EEA for goal-relevant evidence from their use of goal-irrelevant familiarity. We then investigate developmental, cognitive, and clinical correlates of these novel parameters. Parameters for EEA and goal-irrelevant familiarity-based processing showed strong correlations across levels of n-back load, suggesting they are task-general dimensions that influence individuals' performance regardless of working memory demands. Only EEA showed large, robust developmental differences in the ABCD sample and an independent age-diverse sample. EEA also exhibited higher test-retest reliability and uniquely meaningful associations with clinically relevant dimensions. These findings establish a principled modeling framework for characterizing conflict recognition mechanisms and have several broader implications for research on individual and developmental differences in cognitive control.

Background and Aims: This longitudinal study investigated the language skills, phonological working memory and lexical-tone perception of Mandarin-speaking late-talkers (LTs) and those with typical language development (TLD) at 27 months, while also examining their connections with novel word-referent mapping (W-R mapping) through eye-tracking at 33 months. Methods and Procedures: Participants included 22 Mandarin-speaking 27-month-old LTs and 22 toddlers with TLD. Data on expressive and receptive language abilities, as well as phonological working memory and lexical-tone perception, were collected when participants were 27 months old. An eye-tracking paradigm was further employed during the word-learning tasks, which included W-R mapping and word-identification test (W-I test) phases at 33 months. Multilevel models were used to analyse participants' gaze pattern trajectories. Outcomes and Results: At 27 months, LT toddlers exhibited poorer language skills (receptive: p = 0.015, expressive: p < 0.001), lexical-tone perception (p < 0.001) and phonological working memory (p < 0.001) compared to those with TLD, even after considering maternal educational level and participants' fine motor ability. During the W-I test phase, we observed that LT toddlers showed a slower increase in fixations on the novel target image while listening to the corresponding novel word over time, compared to TLD toddlers (linear: p = 0.011, quadratic: p = 0.007) after adding confounders. Further, expressive language ability at 27 months old was a predictor of their newly established W-R mappings at 33 months old (p = 0.016). Additionally, the toddler's phonological working memory and lexical-tone perception were associated with their expressive language ability (p = 0.001 and < 0.001). Conclusions and Implications: These findings indicate that the novel W-R mapping is not as robust in LTs as in TLDs, and the skills necessary for word learning share similarities with a wide range of expressive language abilities. Moreover, poor expressive language abilities were associated with deficits in lexical processing abilities; that is, phonological working memory and lexical-tone perception. These findings suggest the need for interventions aimed at improving LTs' lexical processing abilities to strengthen their lagging word-learning skills at toddlerhood.

Background: Perceptual and speech production abilities of children with cochlear implants (CIs) are usually tested by word and sentence repetition or naming tests. However, these tests are quite far apart from daily life linguistic contexts. Aim: Here, we describe a way of investigating the link between language comprehension and anticipatory verbal behaviour promoting the use of more complex listening situations. Methods and Procedure: The setup consists in watching the audio-visual dialogue of two actors. Children's gaze switches from one speaker to the other serve as a proxy of their prediction abilities. Moreover, to better understand the basis and the impact of anticipatory behaviour, we also measured children's ability to understand the dialogue content, their speech perception and memory skills as well as their rhythmic skills, that also require temporal predictions. Importantly, we compared children with CI performances with those of an age-matched group of children with normal hearing (NH). Outcomes and Results: While children with CI revealed poorer speech perception and verbal working memory abilities than NH children, there was no difference in gaze anticipatory behaviour. Interestingly, in children with CI only, we found a significant correlation between dialogue comprehension, perceptual skills and gaze anticipatory behaviour. Conclusion: Our results extend to a dialogue context of previous findings showing an absence of predictive deficits in children with CI. The current design seems an interesting avenue to provide an accurate and objective estimate of anticipatory language behaviour in a more ecological linguistic context also with young children.

Background: Accurate nonword repetition (NWR) is contingent on many underlying skills, including encoding, memory and motor planning and programming. Though vowel errors are frequently associated with childhood apraxia of speech (CAS), several recent studies have found that children with developmental language disorder (DLD) produce high rates of vowel errors in NWR tasks. Aims: This retrospective analysis explored whether the overall frequency and types of vowel errors produced in NWR distinguish children with DLD, children with CAS, children with speech sound disorder (SSD) and children with typical development (TD). Methods and Procedure: We present data for 24 children (six per DLD, CAS, SSD and TD groups), ranging in age from 50-92 months. Children with DLD, CAS and SSD showed similar articulation scores and children with DLD and children with CAS showed similar expressive language scores. Total vowel errors, total monophthong errors, monophthong substitutions, diphthongization errors, total diphthong errors, diphthong substitutions and diphthong reduction errors were calculated by syllable length and group. Repeated measures analyses of variance were used to examine group differences. Outcomes and Results: Children with DLD and children with CAS produced a higher frequency of total vowel errors compared to children with TD. Children with DLD produced more total monophthong errors than children with TD. Children with DLD and children with CAS produced more total diphthong errors than children with TD. For children with DLD, these were characterised by diphthong substitutions. For children with CAS, these were characterised by diphthong substitutions and diphthong reduction errors. For all measures, error rates in children with SSD did not significantly differ from any of the other three groups. Conclusion: Preliminary evidence indicates that children with DLD and children with CAS both show high rates of vowel errors in NWR tasks and weaknesses in encoding and memory. For children with CAS, additional motor planning difficulties are associated with an increased likelihood to reduce diphthongs. Children with SSD show more mild processing difficulties than children with DLD and children with CAS, though they do not perform as well as TD peers. Future work should replicate and further specify the processing weaknesses that affect vowel accuracy in NWR tasks in a larger sample.

This study provides evidence connecting two aspects of visual-orthographic skills (orthographic awareness and delayed copying) to the common variance shared by Chinese word reading and arithmetic calculation, as well as in identifying positional knowledge of numbers as a potential mediator of these connections in Chinese primary school students (N = 155, 81 boys). Nonverbal Intelligent Quotient (IQ), socioeconomic status (SES), working memory, and attentional control were included as covariates. Path analyses demonstrated that both orthographic awareness and delayed copying significantly explained the covariance of word reading and arithmetic calculation. Furthermore, there is an indirect effect via positional knowledge of numbers as indicated by number line estimation and strategic counting on the relations between orthographic awareness and the common variance shared by word reading and arithmetic calculation. In contrast, delayed copying had a direct effect on the common variance. Results suggest that early visual-orthographic skills may be helpful in the development of both word reading and arithmetic ability among Chinese students.

Previous research has demonstrated the effectiveness of executive functions (EFs) training, both in computer-based and school-based formats. However, there is limited research on the combined effects of these training modalities. This study aims to assess the feasibility and preliminary efficacy of an EFs training programme for primary school children. The programme includes computerized training sessions for home use and school activities with metacognitive elements. The study included a sample of 53 second-grade children, with 21 children in the training group and 32 children in the control group. Feasibility questionnaires were completed by children, parents and teachers. The children also underwent an EFs evaluation. The results indicate that the training was enjoyable for children and feasible for parents and teachers. Furthermore, preliminary efficacy analysis revealed significant improvements in working memory. These findings suggest that the training model holds promise for enhancing EFs in children in the school context.

Background: Rapid automatised naming (RAN) has been found to predict children's reading and arithmetic abilities. However, the underlying mechanisms for its involvement in the two abilities are not clear. This study examines how RAN shared variances with domain-general and domain-specific abilities in predicting reading and arithmetic in Chinese children. Methods: One hundred and sixty-four children (mean age = 8 years 0 months, SD = 4 months) were administered with RAN tasks, word reading and arithmetic tasks and measures of working memory, processing speed, morphological awareness, phonological awareness and number line estimation. Results: RAN mainly shared variance with morphological awareness in predicting word reading, while it shared variance with processing speed and number line estimation in predicting arithmetic calculation. Conclusions: The findings indicated that RAN was related to reading and arithmetic for different reasons. The RAN-reading relationship partly reflected the semantic facilitation of the orthography-phonology links for both RAN stimuli and Chinese characters, while the RAN-arithmetic relationship partly reflected the shared process of retrieving semantic information from long-term memory embedded in the two tasks.

This study investigated the extent to which different pedagogical gestures contribute to learners' foreign or second language (L2) narrative recall, and further discussed how task complexity and task difficulty (i.e. working memory capacity or WMC) influence recall performance. Sixty-four adolescent learners, assigned to four different gesture viewing conditions (iconic gestures, deictic gestures, beat gestures, or no gesture), were required to listen to an instructor telling two stories (one complex and one simple) and then retell both stories twice: once immediately after listening (immediate recall) and a second time two weeks later (delayed recall). Recall performance was evaluated by the number of relevant pieces of event and motion information produced in the participants' retelling. The results show that L2 learners who were exposed to deictic and iconic gesture conditions outperformed the other gesture groups, particularly in delayed narrative recall, but only in complex tasks where cognitive demands were increased. It was also found that event and motion information was retained for a longer period of time in the deictic and iconic conditions respectively. Although both high and low WMC groups benefitted from viewing gestures, this finding further indicates that the beneficial effect of gestures on learners could possibly compensate for low WMC by providing scaffolding that reduces cognitive burden in narrative recall.

This study investigated the extent to which second language (L2) learners benefited from proactive form-focused instruction (FFI) targeting French grammatical gender attribution and the degree to which L2 learners' attention control and working memory predicted their learning gains. A total of 102 L2 learners received either proactive FFI targeting French grammatical gender attribution or their regular instruction (i.e. control condition) for six 80-minute instructional sessions. A pretest, an immediate posttest, and a delayed posttest were administered, each entailing binary-choice, text-completion, picture-description, and listening tasks. The L2 learners also completed the Simon Test and the Corsi Block-Tapping Test, which measured their attention control and working memory. Results showed that L2 learners receiving the proactive FFI condition significantly outperformed those receiving the control condition in all tasks after the instructional sessions. More importantly, L2 learners' attention control and working memory were significant predictors of their learning gains in the binary-choice and listening tasks, but not in the text-completion and picture-description tasks. The current study highlighted the roles of L2 learners' attention control and working memory in proactive FFI.

Visual Reproduction is a condition to measure Visual Spatial Memory as one of the cognitive domains commonly used to measure visuo-spatial memory. Geometric figures serve as stimulus material, and probands have to reproduce the figures from memory through a hand drawing. The scoring of the drawing has subjective elements. This study aims to evaluate the scoring criteria for the Figural Reproduction Test (FRT), part of the Indonesian Neuropsychological Test Battery, and to develop and evaluate an automated scoring system based on computer vision technology (FRT-CVAS). Scoring evaluation conducted by Cohen Kappa analysis, accuracy, sensitivity, and specificity. The analyzes of the three criteria of the manual confirmed a subjective element in the scoring of the shape of triangles by a moderate (0.74) inter-rater agreement; this agreement could be improved to 0.84 by a slight modification of its criteria. FRT-CVAS, based on computer vision's identification of the different elements of the hand drawing, was developed and trained using 290 drawings. The system was additionally tested by comparing its scoring with the scoring of two independent raters on 120 drawings from a second data set. FRT-CVAS recognized all elements, and its comparison between human raters showed a high accuracy and sensitivity (minimally 0.91), while the specificity was 0.80 for one of the three criteria. FRT-CVAS offers a highly standardized, consistent, precise, and objective output from the first card in the FRT. This approach is advantageous to data-hungry alternatives such as deep learning when applied to the automated scoring of hand drawings with relatively little data available for training.

The paper examined the relations among problem solving, automaticity, and working memory load (WML) by changing the difficulty level of task characteristics through two applications. In Study 1, involving 68 engineering students, a 2 (automaticity) x 2 (WML) design was utilized for arithmetic problems. In Study 2, involving 76 engineering students, a 2 (automaticity) x 2 (WML) design was used for linear algebra tasks. In both studies, there were statistically significant main effects and interaction effects of automaticity and WML on the variable of response time, concurring with the cognitive load theory. The simple effect of WML rendered a larger effect size under the conditions with low automaticity. When the testing condition was easy but contained more steps, the students were more accurate, and response times were faster. When the testing condition was difficult but contained fewer steps, the students were less accurate, and response times were slower. The findings underscore the important role of automaticity in helping engineering students bypass the limits of working memory.

This article evaluates the predictions of an algorithmic-level distributed associative memory model as it introduces, propagates, and resolves ambiguity, and compares it to the predictions of computational-level parallel parsing models in which ambiguous analyses are accounted separately in discrete distributions. By superposing activation patterns that serve as cues to other activation patterns, the model is able to maintain multiple syntactically complex analyses superposed in a finite working memory, propagate this ambiguity through multiple intervening words, then resolve this ambiguity in a way that produces a measurable predictor that is proportional to the log conditional probability of the disambiguating word given its context, marginalizing over all remaining analyses. The results are indeed consistent in cases of complex structural ambiguity with computational-level parallel parsing models producing this same probability as a predictor, which have been shown reliably to predict human reading times.

Dropout refers to the phenomenon of students leaving school before completing their degree or program of study. Dropout is a major concern for educational institutions, as it affects not only the students themselves but also the institutions' reputation and funding. Dropout can occur for a variety of reasons, including academic, financial, personal, and social factors. Therefore, understanding the factors that contribute to dropout and developing effective strategies to prevent it is a critical challenge for educational institutions. In this study, we propose a hybrid deep learning model based on Long Short-Term Memory and Deep Neural Network algorithms for school dropout prediction. The proposed model was compared with previous works and several other machine learning algorithms, including Deep Neural Network (DNN), K-Nearest Neighbors (KNN), Naive Bayes (NB), Multi-Layer Perceptron (MLP), Decision Trees (DT), Support Vector Machine (SVM), and Random Forest (RF). The results showed that the proposed DNN-LSTM model outperforms the other models in terms of accuracy and efficiency.

Several studies suggest that a valuable tool to examine linguistic skills in communication disorders is offered by procedures of narrative discourse assessment. Following this line of research, we present an exploratory study aimed to investigate storytelling abilities of autistic children to better define the characteristics of their story production. Participants included 41 autistic children and 41 children with typical development aged between 7.02 and 11.03 years matched on age, gender, level of formal education, intelligence quotient, working memory, attention skills, theory of mind, and phonological short-term memory. Narrative production was assessed by analysing the language samples obtained through the "Nest Story" description task. A multilevel analysis including micro- and macro-linguistic variables was adopted for narrative assessment. Group differences emerged on both micro- and macro-linguistic dimensions: autistic children produced narratives with more phonological errors and semantic paraphasias (microlinguistic variables) as well as more errors of global coherence and a fewer number of visible events and inferred events (macrolinguistic variables) than the control group. This study shows that even autistic children with adequate cognitive skills display several limitations in their narrative competence and that such weaknesses affect both micro- and macrolinguistic aspects of story production.

This study determines the effectiveness of a non-digital picture concept programme to treat cognitive deficits in pupils with dyslexia. Using a sample of 38 primary two pupils (aged 7-9 years) in Ebonyi State, Nigeria, a Picture Concept Activity and the traditional method of repetitive passage drill were administered for eight weeks and results were compared. Standard cognitive and reading measures were used and data were analysed with descriptive and inferential statistics. Results show that the experimental participants performed higher than the control group on the overall reading and cognitive proficiency performances. Improved cognitive proficiency was associated with improved reading tasks.

This study aims to examine the relationship between vocabulary proficiency and short-term memory capacity in deaf or hard-of-hearing (DHH) children. We test the hypothesis that the relationship between vocabulary skills and digit span performance could be strengthened when the digit span task encompasses cross-modal integration processes. A group of DHH children performed two types of auditory digit span tasks. Furthermore, they participated in a standardized vocabulary proficiency test, comprising two subtests: Receptive Vocabulary and Expressive Vocabulary. The verbal digit span served as a significant predictor of Expressive Vocabulary among the DHH children. Simultaneously, the auditory-pointing digit span accounted for a substantial portion of performance variation in both Receptive and Expressive Vocabulary. After considering the impact of the duration of auditory-verbal intervention through regression models, likelihood ratio tests demonstrated that the auditory-pointing digit span persisted as a significant determinant of both receptive and expressive vocabulary skills. A positive influence of the intervention was also confirmed by the present results. This study provides evidence that memory span and the ability to integrate cross-modal information could serve as significant cognitive correlates of vocabulary proficiency in DHH children.

Math anxiety negatively relates to math performance. This negative relationship may be exacerbated in low-progress math learners. However, there are limited studies on math anxiety among low-progress learners in a paradoxically high-performing education system like Singapore. To fill this research gap, this research analyzed the anxiety profiles of 151 students who were in the math learning support intervention program administered by the Ministry of Education, Singapore (MOE). We examined the complex relationship centered in math anxiety with relevant variables such as demographic characteristics, working memory, and math performance. The results indicated that (1) math anxiety only vary significantly between children with very low Early Numeracy Indicator (ENI) and high ENI levels; (2) a negative relationship between math anxiety and math performance exists; (3) there was no significant interaction between math anxiety and working memory; (4) a further examination on moderating effect found that only children who have been identified as being at risk for developmental dyscalculia and those with average or high working memory performed poorer in math at higher levels of math anxiety. Limitations and future directions are discussed.